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[/] [or1k/] [trunk/] [insight/] [tcl/] [generic/] [tclCompile.c] - Blame information for rev 1765

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/*
 * tclCompile.c --
 *
 *      This file contains procedures that compile Tcl commands or parts
 *      of commands (like quoted strings or nested sub-commands) into a
 *      sequence of instructions ("bytecodes").
 *
 * Copyright (c) 1996-1997 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclCompile.c,v 1.1.1.1 2002-01-16 10:25:26 markom Exp $
 */
 
#include "tclInt.h"
#include "tclCompile.h"
 
/*
 * Variable that controls whether compilation tracing is enabled and, if so,
 * what level of tracing is desired:
 *    0: no compilation tracing
 *    1: summarize compilation of top level cmds and proc bodies
 *    2: display all instructions of each ByteCode compiled
 * This variable is linked to the Tcl variable "tcl_traceCompile".
 */
 
int tclTraceCompile = 0;
static int traceInitialized = 0;
 
/*
 * Count of the number of compilations and various other compilation-
 * related statistics.
 */
 
#ifdef TCL_COMPILE_STATS
long tclNumCompilations = 0;
double tclTotalSourceBytes = 0.0;
double tclTotalCodeBytes = 0.0;
 
double tclTotalInstBytes = 0.0;
double tclTotalObjBytes = 0.0;
double tclTotalExceptBytes = 0.0;
double tclTotalAuxBytes = 0.0;
double tclTotalCmdMapBytes = 0.0;
 
double tclCurrentSourceBytes = 0.0;
double tclCurrentCodeBytes = 0.0;
 
int tclSourceCount[32];
int tclByteCodeCount[32];
#endif /* TCL_COMPILE_STATS */
 
/*
 * A table describing the Tcl bytecode instructions. The entries in this
 * table must correspond to the list of instructions in tclInt.h. The names
 * "op1" and "op4" refer to an instruction's one or four byte first operand.
 * Similarly, "stktop" and "stknext" refer to the topmost and next to
 * topmost stack elements.
 *
 * Note that the load, store, and incr instructions do not distinguish local
 * from global variables; the bytecode interpreter at runtime uses the
 * existence of a procedure call frame to distinguish these.
 */
 
InstructionDesc instructionTable[] = {
   /* Name            Bytes #Opnds Operand types        Stack top, next   */
    {"done",              1,   0,   {OPERAND_NONE}},
        /* Finish ByteCode execution and return stktop (top stack item) */
    {"push1",             2,   1,   {OPERAND_UINT1}},
        /* Push object at ByteCode objArray[op1] */
    {"push4",             5,   1,   {OPERAND_UINT4}},
        /* Push object at ByteCode objArray[op4] */
    {"pop",               1,   0,   {OPERAND_NONE}},
        /* Pop the topmost stack object */
    {"dup",               1,   0,   {OPERAND_NONE}},
        /* Duplicate the topmost stack object and push the result */
    {"concat1",           2,   1,   {OPERAND_UINT1}},
        /* Concatenate the top op1 items and push result */
    {"invokeStk1",        2,   1,   {OPERAND_UINT1}},
        /* Invoke command named objv[0]; <objc,objv> = <op1,top op1> */
    {"invokeStk4",        5,   1,   {OPERAND_UINT4}},
        /* Invoke command named objv[0]; <objc,objv> = <op4,top op4> */
    {"evalStk",           1,   0,   {OPERAND_NONE}},
        /* Evaluate command in stktop using Tcl_EvalObj. */
    {"exprStk",           1,   0,   {OPERAND_NONE}},
        /* Execute expression in stktop using Tcl_ExprStringObj. */
 
    {"loadScalar1",       2,   1,   {OPERAND_UINT1}},
        /* Load scalar variable at index op1 <= 255 in call frame */
    {"loadScalar4",       5,   1,   {OPERAND_UINT4}},
        /* Load scalar variable at index op1 >= 256 in call frame */
    {"loadScalarStk",     1,   0,   {OPERAND_NONE}},
        /* Load scalar variable; scalar's name is stktop */
    {"loadArray1",        2,   1,   {OPERAND_UINT1}},
        /* Load array element; array at slot op1<=255, element is stktop */
    {"loadArray4",        5,   1,   {OPERAND_UINT4}},
        /* Load array element; array at slot op1 > 255, element is stktop */
    {"loadArrayStk",      1,   0,   {OPERAND_NONE}},
        /* Load array element; element is stktop, array name is stknext */
    {"loadStk",           1,   0,   {OPERAND_NONE}},
        /* Load general variable; unparsed variable name is stktop */
    {"storeScalar1",      2,   1,   {OPERAND_UINT1}},
        /* Store scalar variable at op1<=255 in frame; value is stktop */
    {"storeScalar4",      5,   1,   {OPERAND_UINT4}},
        /* Store scalar variable at op1 > 255 in frame; value is stktop */
    {"storeScalarStk",    1,   0,   {OPERAND_NONE}},
        /* Store scalar; value is stktop, scalar name is stknext */
    {"storeArray1",       2,   1,   {OPERAND_UINT1}},
        /* Store array element; array at op1<=255, value is top then elem */
    {"storeArray4",       5,   1,   {OPERAND_UINT4}},
        /* Store array element; array at op1>=256, value is top then elem */
    {"storeArrayStk",     1,   0,   {OPERAND_NONE}},
        /* Store array element; value is stktop, then elem, array names */
    {"storeStk",          1,   0,   {OPERAND_NONE}},
        /* Store general variable; value is stktop, then unparsed name */
 
    {"incrScalar1",       2,   1,   {OPERAND_UINT1}},
        /* Incr scalar at index op1<=255 in frame; incr amount is stktop */
    {"incrScalarStk",     1,   0,   {OPERAND_NONE}},
        /* Incr scalar; incr amount is stktop, scalar's name is stknext */
    {"incrArray1",        2,   1,   {OPERAND_UINT1}},
        /* Incr array elem; arr at slot op1<=255, amount is top then elem */
    {"incrArrayStk",      1,   0,   {OPERAND_NONE}},
        /* Incr array element; amount is top then elem then array names */
    {"incrStk",           1,   0,   {OPERAND_NONE}},
        /* Incr general variable; amount is stktop then unparsed var name */
    {"incrScalar1Imm",    3,   2,   {OPERAND_UINT1, OPERAND_INT1}},
        /* Incr scalar at slot op1 <= 255; amount is 2nd operand byte */
    {"incrScalarStkImm",  2,   1,   {OPERAND_INT1}},
        /* Incr scalar; scalar name is stktop; incr amount is op1 */
    {"incrArray1Imm",     3,   2,   {OPERAND_UINT1, OPERAND_INT1}},
        /* Incr array elem; array at slot op1 <= 255, elem is stktop,
         * amount is 2nd operand byte */
    {"incrArrayStkImm",   2,   1,   {OPERAND_INT1}},
        /* Incr array element; elem is top then array name, amount is op1 */
    {"incrStkImm",        2,   1,   {OPERAND_INT1}},
        /* Incr general variable; unparsed name is top, amount is op1 */
 
    {"jump1",             2,   1,   {OPERAND_INT1}},
        /* Jump relative to (pc + op1) */
    {"jump4",             5,   1,   {OPERAND_INT4}},
        /* Jump relative to (pc + op4) */
    {"jumpTrue1",         2,   1,   {OPERAND_INT1}},
        /* Jump relative to (pc + op1) if stktop expr object is true */
    {"jumpTrue4",         5,   1,   {OPERAND_INT4}},
        /* Jump relative to (pc + op4) if stktop expr object is true */
    {"jumpFalse1",        2,   1,   {OPERAND_INT1}},
        /* Jump relative to (pc + op1) if stktop expr object is false */
    {"jumpFalse4",        5,   1,   {OPERAND_INT4}},
        /* Jump relative to (pc + op4) if stktop expr object is false */
 
    {"lor",               1,   0,   {OPERAND_NONE}},
        /* Logical or:  push (stknext || stktop) */
    {"land",              1,   0,   {OPERAND_NONE}},
        /* Logical and: push (stknext && stktop) */
    {"bitor",             1,   0,   {OPERAND_NONE}},
        /* Bitwise or:  push (stknext | stktop) */
    {"bitxor",            1,   0,   {OPERAND_NONE}},
        /* Bitwise xor  push (stknext ^ stktop) */
    {"bitand",            1,   0,   {OPERAND_NONE}},
        /* Bitwise and: push (stknext & stktop) */
    {"eq",                1,   0,   {OPERAND_NONE}},
        /* Equal:       push (stknext == stktop) */
    {"neq",               1,   0,   {OPERAND_NONE}},
        /* Not equal:   push (stknext != stktop) */
    {"lt",                1,   0,   {OPERAND_NONE}},
        /* Less:        push (stknext < stktop) */
    {"gt",                1,   0,   {OPERAND_NONE}},
        /* Greater:     push (stknext || stktop) */
    {"le",                1,   0,   {OPERAND_NONE}},
        /* Logical or:  push (stknext || stktop) */
    {"ge",                1,   0,   {OPERAND_NONE}},
        /* Logical or:  push (stknext || stktop) */
    {"lshift",            1,   0,   {OPERAND_NONE}},
        /* Left shift:  push (stknext << stktop) */
    {"rshift",            1,   0,   {OPERAND_NONE}},
        /* Right shift: push (stknext >> stktop) */
    {"add",               1,   0,   {OPERAND_NONE}},
        /* Add:         push (stknext + stktop) */
    {"sub",               1,   0,   {OPERAND_NONE}},
        /* Sub:         push (stkext - stktop) */
    {"mult",              1,   0,   {OPERAND_NONE}},
        /* Multiply:    push (stknext * stktop) */
    {"div",               1,   0,   {OPERAND_NONE}},
        /* Divide:      push (stknext / stktop) */
    {"mod",               1,   0,   {OPERAND_NONE}},
        /* Mod:         push (stknext % stktop) */
    {"uplus",             1,   0,   {OPERAND_NONE}},
        /* Unary plus:  push +stktop */
    {"uminus",            1,   0,   {OPERAND_NONE}},
        /* Unary minus: push -stktop */
    {"bitnot",            1,   0,   {OPERAND_NONE}},
        /* Bitwise not: push ~stktop */
    {"not",               1,   0,   {OPERAND_NONE}},
        /* Logical not: push !stktop */
    {"callBuiltinFunc1",  2,   1,   {OPERAND_UINT1}},
        /* Call builtin math function with index op1; any args are on stk */
    {"callFunc1",         2,   1,   {OPERAND_UINT1}},
        /* Call non-builtin func objv[0]; <objc,objv>=<op1,top op1>  */
    {"tryCvtToNumeric",   1,   0,   {OPERAND_NONE}},
        /* Try converting stktop to first int then double if possible. */
 
    {"break",             1,   0,   {OPERAND_NONE}},
        /* Abort closest enclosing loop; if none, return TCL_BREAK code. */
    {"continue",          1,   0,   {OPERAND_NONE}},
        /* Skip to next iteration of closest enclosing loop; if none,
         * return TCL_CONTINUE code. */
 
    {"foreach_start4",    5,   1,   {OPERAND_UINT4}},
        /* Initialize execution of a foreach loop. Operand is aux data index
         * of the ForeachInfo structure for the foreach command. */
    {"foreach_step4",     5,   1,   {OPERAND_UINT4}},
        /* "Step" or begin next iteration of foreach loop. Push 0 if to
         *  terminate loop, else push 1. */
 
    {"beginCatch4",       5,   1,   {OPERAND_UINT4}},
        /* Record start of catch with the operand's exception range index.
         * Push the current stack depth onto a special catch stack. */
    {"endCatch",          1,   0,   {OPERAND_NONE}},
        /* End of last catch. Pop the bytecode interpreter's catch stack. */
    {"pushResult",        1,   0,   {OPERAND_NONE}},
        /* Push the interpreter's object result onto the stack. */
    {"pushReturnCode",    1,   0,   {OPERAND_NONE}},
        /* Push interpreter's return code (e.g. TCL_OK or TCL_ERROR) as
         * a new object onto the stack. */
    {0}
};
 
/*
 * The following table assigns a type to each character. Only types
 * meaningful to Tcl parsing are represented here. The table is
 * designed to be referenced with either signed or unsigned characters,
 * so it has 384 entries. The first 128 entries correspond to negative
 * character values, the next 256 correspond to positive character
 * values. The last 128 entries are identical to the first 128. The
 * table is always indexed with a 128-byte offset (the 128th entry
 * corresponds to a 0 character value).
 */
 
unsigned char tclTypeTable[] = {
    /*
     * Negative character values, from -128 to -1:
     */
 
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
 
    /*
     * Positive character values, from 0-127:
     */
 
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_SPACE,         TCL_COMMAND_END,   TCL_SPACE,
    TCL_SPACE,         TCL_SPACE,         TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_SPACE,         TCL_NORMAL,        TCL_QUOTE,         TCL_NORMAL,
    TCL_DOLLAR,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_COMMAND_END,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_OPEN_BRACKET,
    TCL_BACKSLASH,     TCL_COMMAND_END,   TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_OPEN_BRACE,
    TCL_NORMAL,        TCL_CLOSE_BRACE,   TCL_NORMAL,        TCL_NORMAL,
 
    /*
     * Large unsigned character values, from 128-255:
     */
 
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
    TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,        TCL_NORMAL,
};
 
/*
 * Table of all AuxData types.
 */
 
static Tcl_HashTable auxDataTypeTable;
static int auxDataTypeTableInitialized = 0;    /* 0 means not yet
                                                * initialized. */
 
/*
 * Prototypes for procedures defined later in this file:
 */
 
static void             AdvanceToNextWord _ANSI_ARGS_((char *string,
                            CompileEnv *envPtr));
static int              CollectArgInfo _ANSI_ARGS_((Tcl_Interp *interp,
                            char *string, char *lastChar, int flags,
                            ArgInfo *argInfoPtr));
static int              CompileBraces _ANSI_ARGS_((Tcl_Interp *interp,
                            char *string, char *lastChar, int flags,
                            CompileEnv *envPtr));
static int              CompileCmdWordInline _ANSI_ARGS_((
                            Tcl_Interp *interp, char *string,
                            char *lastChar, int flags, CompileEnv *envPtr));
static int              CompileExprWord _ANSI_ARGS_((Tcl_Interp *interp,
                            char *string, char *lastChar, int flags,
                            CompileEnv *envPtr));
static int              CompileMultipartWord _ANSI_ARGS_((
                            Tcl_Interp *interp, char *string,
                            char *lastChar, int flags, CompileEnv *envPtr));
static int              CompileWord _ANSI_ARGS_((Tcl_Interp *interp,
                            char *string, char *lastChar, int flags,
                            CompileEnv *envPtr));
static int              CreateExceptionRange _ANSI_ARGS_((
                            ExceptionRangeType type, CompileEnv *envPtr));
static void             DupByteCodeInternalRep _ANSI_ARGS_((Tcl_Obj *srcPtr,
                            Tcl_Obj *copyPtr));
static ClientData       DupForeachInfo _ANSI_ARGS_((ClientData clientData));
static unsigned char *  EncodeCmdLocMap _ANSI_ARGS_((
                            CompileEnv *envPtr, ByteCode *codePtr,
                            unsigned char *startPtr));
static void             EnterCmdExtentData _ANSI_ARGS_((
                            CompileEnv *envPtr, int cmdNumber,
                            int numSrcChars, int numCodeBytes));
static void             EnterCmdStartData _ANSI_ARGS_((
                            CompileEnv *envPtr, int cmdNumber,
                            int srcOffset, int codeOffset));
static void             ExpandObjectArray _ANSI_ARGS_((CompileEnv *envPtr));
static void             FreeForeachInfo _ANSI_ARGS_((
                            ClientData clientData));
static void             FreeByteCodeInternalRep _ANSI_ARGS_((
                            Tcl_Obj *objPtr));
static void             FreeArgInfo _ANSI_ARGS_((ArgInfo *argInfoPtr));
static int              GetCmdLocEncodingSize _ANSI_ARGS_((
                            CompileEnv *envPtr));
static void             InitArgInfo _ANSI_ARGS_((ArgInfo *argInfoPtr));
static int              IsLocalScalar  _ANSI_ARGS_((char *name, int len));
static int              LookupCompiledLocal _ANSI_ARGS_((
                            char *name, int nameChars, int createIfNew,
                            int flagsIfCreated, Proc *procPtr));
static int              SetByteCodeFromAny _ANSI_ARGS_((Tcl_Interp *interp,
                            Tcl_Obj *objPtr));
static void             UpdateStringOfByteCode _ANSI_ARGS_((Tcl_Obj *objPtr));
 
/*
 * The structure below defines the bytecode Tcl object type by
 * means of procedures that can be invoked by generic object code.
 */
 
Tcl_ObjType tclByteCodeType = {
    "bytecode",                 /* name */
    FreeByteCodeInternalRep,    /* freeIntRepProc */
    DupByteCodeInternalRep,     /* dupIntRepProc */
    UpdateStringOfByteCode,     /* updateStringProc */
    SetByteCodeFromAny          /* setFromAnyProc */
};
 
/*
 * The structures below define the AuxData types defined in this file.
 */
 
AuxDataType tclForeachInfoType = {
    "ForeachInfo",                              /* name */
    DupForeachInfo,                             /* dupProc */
    FreeForeachInfo                             /* freeProc */
};
 
/*
 *----------------------------------------------------------------------
 *
 * TclPrintByteCodeObj --
 *
 *      This procedure prints ("disassembles") the instructions of a
 *      bytecode object to stdout.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
 
void
TclPrintByteCodeObj(interp, objPtr)
    Tcl_Interp *interp;         /* Used only for Tcl_GetStringFromObj. */
    Tcl_Obj *objPtr;            /* The bytecode object to disassemble. */
{
    ByteCode* codePtr = (ByteCode *) objPtr->internalRep.otherValuePtr;
    unsigned char *codeStart, *codeLimit, *pc;
    unsigned char *codeDeltaNext, *codeLengthNext;
    unsigned char *srcDeltaNext, *srcLengthNext;
    int codeOffset, codeLen, srcOffset, srcLen;
    int numCmds, numObjs, delta, objBytes, i;
 
    if (codePtr->refCount <= 0) {
        return;                 /* already freed */
    }
 
    codeStart = codePtr->codeStart;
    codeLimit = (codeStart + codePtr->numCodeBytes);
    numCmds = codePtr->numCommands;
    numObjs = codePtr->numObjects;
 
    objBytes = (numObjs * sizeof(Tcl_Obj));
    for (i = 0;  i < numObjs;  i++) {
        Tcl_Obj *litObjPtr = codePtr->objArrayPtr[i];
        if (litObjPtr->bytes != NULL) {
            objBytes += litObjPtr->length;
        }
    }
 
    /*
     * Print header lines describing the ByteCode.
     */
 
    fprintf(stdout, "\nByteCode 0x%x, ref ct %u, epoch %u, interp 0x%x(epoch %u)\n",
            (unsigned int) codePtr, codePtr->refCount,
            codePtr->compileEpoch, (unsigned int) codePtr->iPtr,
            codePtr->iPtr->compileEpoch);
    fprintf(stdout, "  Source ");
    TclPrintSource(stdout, codePtr->source,
            TclMin(codePtr->numSrcChars, 70));
    fprintf(stdout, "\n  Cmds %d, chars %d, inst %d, objs %u, aux %d, stk depth %u, code/src %.2f\n",
            numCmds, codePtr->numSrcChars, codePtr->numCodeBytes, numObjs,
            codePtr->numAuxDataItems, codePtr->maxStackDepth,
            (codePtr->numSrcChars?
                    ((float)codePtr->totalSize)/((float)codePtr->numSrcChars) : 0.0));
    fprintf(stdout, "  Code %d = %d(header)+%d(inst)+%d(objs)+%d(exc)+%d(aux)+%d(cmd map)\n",
            codePtr->totalSize, sizeof(ByteCode), codePtr->numCodeBytes,
            objBytes, (codePtr->numExcRanges * sizeof(ExceptionRange)),
            (codePtr->numAuxDataItems * sizeof(AuxData)),
            codePtr->numCmdLocBytes);
 
    /*
     * If the ByteCode is the compiled body of a Tcl procedure, print
     * information about that procedure. Note that we don't know the
     * procedure's name since ByteCode's can be shared among procedures.
     */
 
    if (codePtr->procPtr != NULL) {
        Proc *procPtr = codePtr->procPtr;
        int numCompiledLocals = procPtr->numCompiledLocals;
        fprintf(stdout,
                "  Proc 0x%x, ref ct %d, args %d, compiled locals %d\n",
                (unsigned int) procPtr, procPtr->refCount, procPtr->numArgs,
                numCompiledLocals);
        if (numCompiledLocals > 0) {
            CompiledLocal *localPtr = procPtr->firstLocalPtr;
            for (i = 0;  i < numCompiledLocals;  i++) {
                fprintf(stdout, "      %d: slot %d%s%s%s%s%s%s",
                        i, localPtr->frameIndex,
                        ((localPtr->flags & VAR_SCALAR)?  ", scalar"  : ""),
                        ((localPtr->flags & VAR_ARRAY)?  ", array"  : ""),
                        ((localPtr->flags & VAR_LINK)?  ", link"  : ""),
                        ((localPtr->flags & VAR_ARGUMENT)?  ", arg"  : ""),
                        ((localPtr->flags & VAR_TEMPORARY)? ", temp" : ""),
                        ((localPtr->flags & VAR_RESOLVED)? ", resolved" : ""));
                if (TclIsVarTemporary(localPtr)) {
                    fprintf(stdout,     "\n");
                } else {
                    fprintf(stdout,     ", name=\"%s\"\n", localPtr->name);
                }
                localPtr = localPtr->nextPtr;
            }
        }
    }
 
    /*
     * Print the ExceptionRange array.
     */
 
    if (codePtr->numExcRanges > 0) {
        fprintf(stdout, "  Exception ranges %d, depth %d:\n",
                codePtr->numExcRanges, codePtr->maxExcRangeDepth);
        for (i = 0;  i < codePtr->numExcRanges;  i++) {
            ExceptionRange *rangePtr = &(codePtr->excRangeArrayPtr[i]);
            fprintf(stdout, "      %d: level %d, %s, pc %d-%d, ",
                    i, rangePtr->nestingLevel,
                    ((rangePtr->type == LOOP_EXCEPTION_RANGE)? "loop":"catch"),
                    rangePtr->codeOffset,
                    (rangePtr->codeOffset + rangePtr->numCodeBytes - 1));
            switch (rangePtr->type) {
            case LOOP_EXCEPTION_RANGE:
                fprintf(stdout, "continue %d, break %d\n",
                        rangePtr->continueOffset, rangePtr->breakOffset);
                break;
            case CATCH_EXCEPTION_RANGE:
                fprintf(stdout, "catch %d\n", rangePtr->catchOffset);
                break;
            default:
                panic("TclPrintSource: unrecognized ExceptionRange type %d\n",
                        rangePtr->type);
            }
        }
    }
 
    /*
     * If there were no commands (e.g., an expression or an empty string
     * was compiled), just print all instructions and return.
     */
 
    if (numCmds == 0) {
        pc = codeStart;
        while (pc < codeLimit) {
            fprintf(stdout, "    ");
            pc += TclPrintInstruction(codePtr, pc);
        }
        return;
    }
 
    /*
     * Print table showing the code offset, source offset, and source
     * length for each command. These are encoded as a sequence of bytes.
     */
 
    fprintf(stdout, "  Commands %d:", numCmds);
    codeDeltaNext = codePtr->codeDeltaStart;
    codeLengthNext = codePtr->codeLengthStart;
    srcDeltaNext  = codePtr->srcDeltaStart;
    srcLengthNext = codePtr->srcLengthStart;
    codeOffset = srcOffset = 0;
    for (i = 0;  i < numCmds;  i++) {
        if ((unsigned int) (*codeDeltaNext) == (unsigned int) 0xFF) {
            codeDeltaNext++;
            delta = TclGetInt4AtPtr(codeDeltaNext);
            codeDeltaNext += 4;
        } else {
            delta = TclGetInt1AtPtr(codeDeltaNext);
            codeDeltaNext++;
        }
        codeOffset += delta;
 
        if ((unsigned int) (*codeLengthNext) == (unsigned int) 0xFF) {
            codeLengthNext++;
            codeLen = TclGetInt4AtPtr(codeLengthNext);
            codeLengthNext += 4;
        } else {
            codeLen = TclGetInt1AtPtr(codeLengthNext);
            codeLengthNext++;
        }
 
        if ((unsigned int) (*srcDeltaNext) == (unsigned int) 0xFF) {
            srcDeltaNext++;
            delta = TclGetInt4AtPtr(srcDeltaNext);
            srcDeltaNext += 4;
        } else {
            delta = TclGetInt1AtPtr(srcDeltaNext);
            srcDeltaNext++;
        }
        srcOffset += delta;
 
        if ((unsigned int) (*srcLengthNext) == (unsigned int) 0xFF) {
            srcLengthNext++;
            srcLen = TclGetInt4AtPtr(srcLengthNext);
            srcLengthNext += 4;
        } else {
            srcLen = TclGetInt1AtPtr(srcLengthNext);
            srcLengthNext++;
        }
 
        fprintf(stdout, "%s%4d: pc %d-%d, source %d-%d",
                ((i % 2)? "     " : "\n   "),
                (i+1), codeOffset, (codeOffset + codeLen - 1),
                srcOffset, (srcOffset + srcLen - 1));
    }
    if ((numCmds > 0) && ((numCmds % 2) != 0)) {
        fprintf(stdout, "\n");
    }
 
    /*
     * Print each instruction. If the instruction corresponds to the start
     * of a command, print the command's source. Note that we don't need
     * the code length here.
     */
 
    codeDeltaNext = codePtr->codeDeltaStart;
    srcDeltaNext  = codePtr->srcDeltaStart;
    srcLengthNext = codePtr->srcLengthStart;
    codeOffset = srcOffset = 0;
    pc = codeStart;
    for (i = 0;  i < numCmds;  i++) {
        if ((unsigned int) (*codeDeltaNext) == (unsigned int) 0xFF) {
            codeDeltaNext++;
            delta = TclGetInt4AtPtr(codeDeltaNext);
            codeDeltaNext += 4;
        } else {
            delta = TclGetInt1AtPtr(codeDeltaNext);
            codeDeltaNext++;
        }
        codeOffset += delta;
 
        if ((unsigned int) (*srcDeltaNext) == (unsigned int) 0xFF) {
            srcDeltaNext++;
            delta = TclGetInt4AtPtr(srcDeltaNext);
            srcDeltaNext += 4;
        } else {
            delta = TclGetInt1AtPtr(srcDeltaNext);
            srcDeltaNext++;
        }
        srcOffset += delta;
 
        if ((unsigned int) (*srcLengthNext) == (unsigned int) 0xFF) {
            srcLengthNext++;
            srcLen = TclGetInt4AtPtr(srcLengthNext);
            srcLengthNext += 4;
        } else {
            srcLen = TclGetInt1AtPtr(srcLengthNext);
            srcLengthNext++;
        }
 
        /*
         * Print instructions before command i.
         */
 
        while ((pc-codeStart) < codeOffset) {
            fprintf(stdout, "    ");
            pc += TclPrintInstruction(codePtr, pc);
        }
 
        fprintf(stdout, "  Command %d: ", (i+1));
        TclPrintSource(stdout, (codePtr->source + srcOffset),
                TclMin(srcLen, 70));
        fprintf(stdout, "\n");
    }
    if (pc < codeLimit) {
        /*
         * Print instructions after the last command.
         */
 
        while (pc < codeLimit) {
            fprintf(stdout, "    ");
            pc += TclPrintInstruction(codePtr, pc);
        }
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclPrintInstruction --
 *
 *      This procedure prints ("disassembles") one instruction from a
 *      bytecode object to stdout.
 *
 * Results:
 *      Returns the length in bytes of the current instruiction.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
 
int
TclPrintInstruction(codePtr, pc)
    ByteCode* codePtr;          /* Bytecode containing the instruction. */
    unsigned char *pc;          /* Points to first byte of instruction. */
{
    Proc *procPtr = codePtr->procPtr;
    unsigned char opCode = *pc;
    register InstructionDesc *instDesc = &instructionTable[opCode];
    unsigned char *codeStart = codePtr->codeStart;
    unsigned int pcOffset = (pc - codeStart);
    int opnd, elemLen, i, j;
    Tcl_Obj *elemPtr;
    char *string;
 
    fprintf(stdout, "(%u) %s ", pcOffset, instDesc->name);
    for (i = 0;  i < instDesc->numOperands;  i++) {
        switch (instDesc->opTypes[i]) {
        case OPERAND_INT1:
            opnd = TclGetInt1AtPtr(pc+1+i);
            if ((i == 0) && ((opCode == INST_JUMP1)
                             || (opCode == INST_JUMP_TRUE1)
                             || (opCode == INST_JUMP_FALSE1))) {
                fprintf(stdout, "%d     # pc %u", opnd, (pcOffset + opnd));
            } else {
                fprintf(stdout, "%d", opnd);
            }
            break;
        case OPERAND_INT4:
            opnd = TclGetInt4AtPtr(pc+1+i);
            if ((i == 0) && ((opCode == INST_JUMP4)
                             || (opCode == INST_JUMP_TRUE4)
                             || (opCode == INST_JUMP_FALSE4))) {
                fprintf(stdout, "%d     # pc %u", opnd, (pcOffset + opnd));
            } else {
                fprintf(stdout, "%d", opnd);
            }
            break;
        case OPERAND_UINT1:
            opnd = TclGetUInt1AtPtr(pc+1+i);
            if ((i == 0) && (opCode == INST_PUSH1)) {
                elemPtr = codePtr->objArrayPtr[opnd];
                string = Tcl_GetStringFromObj(elemPtr, &elemLen);
                fprintf(stdout, "%u     # ", (unsigned int) opnd);
                TclPrintSource(stdout, string, TclMin(elemLen, 40));
            } else if ((i == 0) && ((opCode == INST_LOAD_SCALAR1)
                                    || (opCode == INST_LOAD_ARRAY1)
                                    || (opCode == INST_STORE_SCALAR1)
                                    || (opCode == INST_STORE_ARRAY1))) {
                int localCt = procPtr->numCompiledLocals;
                CompiledLocal *localPtr = procPtr->firstLocalPtr;
                if (opnd >= localCt) {
                    panic("TclPrintInstruction: bad local var index %u (%u locals)\n",
                             (unsigned int) opnd, localCt);
                    return instDesc->numBytes;
                }
                for (j = 0;  j < opnd;  j++) {
                    localPtr = localPtr->nextPtr;
                }
                if (TclIsVarTemporary(localPtr)) {
                    fprintf(stdout, "%u # temp var %u",
                            (unsigned int) opnd, (unsigned int) opnd);
                } else {
                    fprintf(stdout, "%u # var ", (unsigned int) opnd);
                    TclPrintSource(stdout, localPtr->name, 40);
                }
            } else {
                fprintf(stdout, "%u ", (unsigned int) opnd);
            }
            break;
        case OPERAND_UINT4:
            opnd = TclGetUInt4AtPtr(pc+1+i);
            if (opCode == INST_PUSH4) {
                elemPtr = codePtr->objArrayPtr[opnd];
                string = Tcl_GetStringFromObj(elemPtr, &elemLen);
                fprintf(stdout, "%u     # ", opnd);
                TclPrintSource(stdout, string, TclMin(elemLen, 40));
            } else if ((i == 0) && ((opCode == INST_LOAD_SCALAR4)
                                    || (opCode == INST_LOAD_ARRAY4)
                                    || (opCode == INST_STORE_SCALAR4)
                                    || (opCode == INST_STORE_ARRAY4))) {
                int localCt = procPtr->numCompiledLocals;
                CompiledLocal *localPtr = procPtr->firstLocalPtr;
                if (opnd >= localCt) {
                    panic("TclPrintInstruction: bad local var index %u (%u locals)\n",
                             (unsigned int) opnd, localCt);
                    return instDesc->numBytes;
                }
                for (j = 0;  j < opnd;  j++) {
                    localPtr = localPtr->nextPtr;
                }
                if (TclIsVarTemporary(localPtr)) {
                    fprintf(stdout, "%u # temp var %u",
                            (unsigned int) opnd, (unsigned int) opnd);
                } else {
                    fprintf(stdout, "%u # var ", (unsigned int) opnd);
                    TclPrintSource(stdout, localPtr->name, 40);
                }
            } else {
                fprintf(stdout, "%u ", (unsigned int) opnd);
            }
            break;
        case OPERAND_NONE:
        default:
            break;
        }
    }
    fprintf(stdout, "\n");
    return instDesc->numBytes;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclPrintSource --
 *
 *      This procedure prints up to a specified number of characters from
 *      the argument string to a specified file. It tries to produce legible
 *      output by adding backslashes as necessary.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Outputs characters to the specified file.
 *
 *----------------------------------------------------------------------
 */
 
void
TclPrintSource(outFile, string, maxChars)
    FILE *outFile;              /* The file to print the source to. */
    char *string;               /* The string to print. */
    int maxChars;               /* Maximum number of chars to print. */
{
    register char *p;
    register int i = 0;
 
    if (string == NULL) {
        fprintf(outFile, "\"\"");
        return;
    }
 
    fprintf(outFile, "\"");
    p = string;
    for (;  (*p != '\0') && (i < maxChars);  p++, i++) {
        switch (*p) {
            case '"':
                fprintf(outFile, "\\\"");
                continue;
            case '\f':
                fprintf(outFile, "\\f");
                continue;
            case '\n':
                fprintf(outFile, "\\n");
                continue;
            case '\r':
                fprintf(outFile, "\\r");
                continue;
            case '\t':
                fprintf(outFile, "\\t");
                continue;
            case '\v':
                fprintf(outFile, "\\v");
                continue;
            default:
                fprintf(outFile, "%c", *p);
                continue;
        }
    }
    fprintf(outFile, "\"");
}
 
/*
 *----------------------------------------------------------------------
 *
 * FreeByteCodeInternalRep --
 *
 *      Part of the bytecode Tcl object type implementation. Frees the
 *      storage associated with a bytecode object's internal representation
 *      unless its code is actively being executed.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The bytecode object's internal rep is marked invalid and its
 *      code gets freed unless the code is actively being executed.
 *      In that case the cleanup is delayed until the last execution
 *      of the code completes.
 *
 *----------------------------------------------------------------------
 */
 
static void
FreeByteCodeInternalRep(objPtr)
    register Tcl_Obj *objPtr;   /* Object whose internal rep to free. */
{
    register ByteCode *codePtr =
            (ByteCode *) objPtr->internalRep.otherValuePtr;
 
    codePtr->refCount--;
    if (codePtr->refCount <= 0) {
        TclCleanupByteCode(codePtr);
    }
    objPtr->typePtr = NULL;
    objPtr->internalRep.otherValuePtr = NULL;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCleanupByteCode --
 *
 *      This procedure does all the real work of freeing up a bytecode
 *      object's ByteCode structure. It's called only when the structure's
 *      reference count becomes zero.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Frees objPtr's bytecode internal representation and sets
 *      its type and objPtr->internalRep.otherValuePtr NULL. Also
 *      decrements the ref counts on each object in its object array,
 *      and frees its auxiliary data items.
 *
 *----------------------------------------------------------------------
 */
 
void
TclCleanupByteCode(codePtr)
    ByteCode *codePtr;          /* ByteCode to free. */
{
    Tcl_Obj **objArrayPtr = codePtr->objArrayPtr;
    int numObjects = codePtr->numObjects;
    int numAuxDataItems = codePtr->numAuxDataItems;
    register AuxData *auxDataPtr;
    register Tcl_Obj *elemPtr;
    register int i;
 
#ifdef TCL_COMPILE_STATS    
    tclCurrentSourceBytes -= (double) codePtr->numSrcChars;
    tclCurrentCodeBytes -= (double) codePtr->totalSize;
#endif /* TCL_COMPILE_STATS */
 
    /*
     * A single heap object holds the ByteCode structure and its code,
     * object, command location, and auxiliary data arrays. This means we
     * only need to 1) decrement the ref counts on the objects in its
     * object array, 2) call the free procs for the auxiliary data items,
     * and 3) free the ByteCode structure's heap object.
     */
 
    for (i = 0;  i < numObjects;  i++) {
        elemPtr = objArrayPtr[i];
        TclDecrRefCount(elemPtr);
    }
 
    auxDataPtr = codePtr->auxDataArrayPtr;
    for (i = 0;  i < numAuxDataItems;  i++) {
        if (auxDataPtr->type->freeProc != NULL) {
            auxDataPtr->type->freeProc(auxDataPtr->clientData);
        }
        auxDataPtr++;
    }
 
    ckfree((char *) codePtr);
}
 
/*
 *----------------------------------------------------------------------
 *
 * DupByteCodeInternalRep --
 *
 *      Part of the bytecode Tcl object type implementation. However, it
 *      does not copy the internal representation of a bytecode Tcl_Obj, but
 *      instead leaves the new object untyped (with a NULL type pointer).
 *      Code will be compiled for the new object only if necessary.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
 
static void
DupByteCodeInternalRep(srcPtr, copyPtr)
    Tcl_Obj *srcPtr;            /* Object with internal rep to copy. */
    Tcl_Obj *copyPtr;           /* Object with internal rep to set. */
{
    return;
}
 
/*
 *-----------------------------------------------------------------------
 *
 * SetByteCodeFromAny --
 *
 *      Part of the bytecode Tcl object type implementation. Attempts to
 *      generate an byte code internal form for the Tcl object "objPtr" by
 *      compiling its string representation.
 *
 * Results:
 *      The return value is a standard Tcl object result. If an error occurs
 *      during compilation, an error message is left in the interpreter's
 *      result unless "interp" is NULL.
 *
 * Side effects:
 *      Frees the old internal representation. If no error occurs, then the
 *      compiled code is stored as "objPtr"s bytecode representation.
 *      Also, if debugging, initializes the "tcl_traceCompile" Tcl variable
 *      used to trace compilations.
 *
 *----------------------------------------------------------------------
 */
 
static int
SetByteCodeFromAny(interp, objPtr)
    Tcl_Interp *interp;         /* The interpreter for which the code is
                                 * compiled. */
    Tcl_Obj *objPtr;            /* The object to convert. */
{
    Interp *iPtr = (Interp *) interp;
    char *string;
    CompileEnv compEnv;         /* Compilation environment structure
                                 * allocated in frame. */
    AuxData *auxDataPtr;
    register int i;
    int length, result;
 
    if (!traceInitialized) {
        if (Tcl_LinkVar(interp, "tcl_traceCompile",
                    (char *) &tclTraceCompile,  TCL_LINK_INT) != TCL_OK) {
            panic("SetByteCodeFromAny: unable to create link for tcl_traceCompile variable");
        }
        traceInitialized = 1;
    }
 
    string = Tcl_GetStringFromObj(objPtr, &length);
    TclInitCompileEnv(interp, &compEnv, string);
    result = TclCompileString(interp, string, string+length,
            iPtr->evalFlags, &compEnv);
    if (result == TCL_OK) {
        /*
         * Add a "done" instruction at the end of the instruction sequence.
         */
 
        TclEmitOpcode(INST_DONE, &compEnv);
 
        /*
         * Convert the object to a ByteCode object.
         */
 
        TclInitByteCodeObj(objPtr, &compEnv);
    } else {
        /*
         * Compilation errors. Decrement the ref counts on any objects in
         * the object array and free any aux data items prior to freeing
         * the compilation environment.
         */
 
        for (i = 0;  i < compEnv.objArrayNext;  i++) {
            Tcl_Obj *elemPtr = compEnv.objArrayPtr[i];
            Tcl_DecrRefCount(elemPtr);
        }
 
        auxDataPtr = compEnv.auxDataArrayPtr;
        for (i = 0;  i < compEnv.auxDataArrayNext;  i++) {
            if (auxDataPtr->type->freeProc != NULL) {
            auxDataPtr->type->freeProc(auxDataPtr->clientData);
            }
            auxDataPtr++;
        }
    }
    TclFreeCompileEnv(&compEnv);
 
    if (result == TCL_OK) {
        if (tclTraceCompile == 2) {
            TclPrintByteCodeObj(interp, objPtr);
        }
    }
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * UpdateStringOfByteCode --
 *
 *      Part of the bytecode Tcl object type implementation. Called to
 *      update the string representation for a byte code object.
 *      Note: This procedure does not free an existing old string rep
 *      so storage will be lost if this has not already been done.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Generates a panic.
 *
 *----------------------------------------------------------------------
 */
 
static void
UpdateStringOfByteCode(objPtr)
    register Tcl_Obj *objPtr;   /* ByteCode object with string rep that
                                 * needs updating. */
{
    /*
     * This procedure is never invoked since the internal representation of
     * a bytecode object is never modified.
     */
 
    panic("UpdateStringOfByteCode should never be called.");
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclInitCompileEnv --
 *
 *      Initializes a CompileEnv compilation environment structure for the
 *      compilation of a string in an interpreter.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The CompileEnv structure is initialized.
 *
 *----------------------------------------------------------------------
 */
 
void
TclInitCompileEnv(interp, envPtr, string)
    Tcl_Interp *interp;          /* The interpreter for which a CompileEnv
                                  * structure is initialized. */
    register CompileEnv *envPtr; /* Points to the CompileEnv structure to
                                  * initialize. */
    char *string;                /* The source string to be compiled. */
{
    Interp *iPtr = (Interp *) interp;
 
    envPtr->iPtr = iPtr;
    envPtr->source = string;
    envPtr->procPtr = iPtr->compiledProcPtr;
    envPtr->numCommands = 0;
    envPtr->excRangeDepth = 0;
    envPtr->maxExcRangeDepth = 0;
    envPtr->maxStackDepth = 0;
    Tcl_InitHashTable(&(envPtr->objTable), TCL_STRING_KEYS);
    envPtr->pushSimpleWords = 1;
    envPtr->wordIsSimple = 0;
    envPtr->numSimpleWordChars = 0;
    envPtr->exprIsJustVarRef = 0;
    envPtr->exprIsComparison = 0;
    envPtr->termOffset = 0;
 
    envPtr->codeStart = envPtr->staticCodeSpace;
    envPtr->codeNext = envPtr->codeStart;
    envPtr->codeEnd = (envPtr->codeStart + COMPILEENV_INIT_CODE_BYTES);
    envPtr->mallocedCodeArray = 0;
 
    envPtr->objArrayPtr = envPtr->staticObjArraySpace;
    envPtr->objArrayNext = 0;
    envPtr->objArrayEnd = COMPILEENV_INIT_NUM_OBJECTS;
    envPtr->mallocedObjArray = 0;
 
    envPtr->excRangeArrayPtr = envPtr->staticExcRangeArraySpace;
    envPtr->excRangeArrayNext = 0;
    envPtr->excRangeArrayEnd = COMPILEENV_INIT_EXCEPT_RANGES;
    envPtr->mallocedExcRangeArray = 0;
 
    envPtr->cmdMapPtr = envPtr->staticCmdMapSpace;
    envPtr->cmdMapEnd = COMPILEENV_INIT_CMD_MAP_SIZE;
    envPtr->mallocedCmdMap = 0;
 
    envPtr->auxDataArrayPtr = envPtr->staticAuxDataArraySpace;
    envPtr->auxDataArrayNext = 0;
    envPtr->auxDataArrayEnd = COMPILEENV_INIT_AUX_DATA_SIZE;
    envPtr->mallocedAuxDataArray = 0;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclFreeCompileEnv --
 *
 *      Free the storage allocated in a CompileEnv compilation environment
 *      structure.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Allocated storage in the CompileEnv structure is freed. Note that
 *      ref counts for Tcl objects in its object table are not decremented.
 *      In addition, any storage referenced by any auxiliary data items
 *      in the CompileEnv structure are not freed either. The expectation
 *      is that when compilation is successful, "ownership" (i.e., the
 *      pointers to) these objects and aux data items will just be handed
 *      over to the corresponding ByteCode structure.
 *
 *----------------------------------------------------------------------
 */
 
void
TclFreeCompileEnv(envPtr)
    register CompileEnv *envPtr; /* Points to the CompileEnv structure. */
{
    Tcl_DeleteHashTable(&(envPtr->objTable));
    if (envPtr->mallocedCodeArray) {
        ckfree((char *) envPtr->codeStart);
    }
    if (envPtr->mallocedObjArray) {
        ckfree((char *) envPtr->objArrayPtr);
    }
    if (envPtr->mallocedExcRangeArray) {
        ckfree((char *) envPtr->excRangeArrayPtr);
    }
    if (envPtr->mallocedCmdMap) {
        ckfree((char *) envPtr->cmdMapPtr);
    }
    if (envPtr->mallocedAuxDataArray) {
        ckfree((char *) envPtr->auxDataArrayPtr);
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclInitByteCodeObj --
 *
 *      Create a ByteCode structure and initialize it from a CompileEnv
 *      compilation environment structure. The ByteCode structure is
 *      smaller and contains just that information needed to execute
 *      the bytecode instructions resulting from compiling a Tcl script.
 *      The resulting structure is placed in the specified object.
 *
 * Results:
 *      A newly constructed ByteCode object is stored in the internal
 *      representation of the objPtr.
 *
 * Side effects:
 *      A single heap object is allocated to hold the new ByteCode structure
 *      and its code, object, command location, and aux data arrays. Note
 *      that "ownership" (i.e., the pointers to) the Tcl objects and aux
 *      data items will be handed over to the new ByteCode structure from
 *      the CompileEnv structure.
 *
 *----------------------------------------------------------------------
 */
 
void
TclInitByteCodeObj(objPtr, envPtr)
    Tcl_Obj *objPtr;             /* Points object that should be
                                  * initialized, and whose string rep
                                  * contains the source code. */
    register CompileEnv *envPtr; /* Points to the CompileEnv structure from
                                  * which to create a ByteCode structure. */
{
    register ByteCode *codePtr;
    size_t codeBytes, objArrayBytes, exceptArrayBytes, cmdLocBytes;
    size_t auxDataArrayBytes;
    register size_t size, objBytes, totalSize;
    register unsigned char *p;
    unsigned char *nextPtr;
    int srcLen = envPtr->termOffset;
    int numObjects, i;
    Namespace *namespacePtr;
#ifdef TCL_COMPILE_STATS
    int srcLenLog2, sizeLog2;
#endif /*TCL_COMPILE_STATS*/
 
    codeBytes = (envPtr->codeNext - envPtr->codeStart);
    numObjects = envPtr->objArrayNext;
    objArrayBytes = (envPtr->objArrayNext * sizeof(Tcl_Obj *));
    exceptArrayBytes = (envPtr->excRangeArrayNext * sizeof(ExceptionRange));
    auxDataArrayBytes = (envPtr->auxDataArrayNext * sizeof(AuxData));
    cmdLocBytes = GetCmdLocEncodingSize(envPtr);
 
    size = sizeof(ByteCode);
    size += TCL_ALIGN(codeBytes);       /* align object array */
    size += TCL_ALIGN(objArrayBytes);   /* align exception range array */
    size += TCL_ALIGN(exceptArrayBytes); /* align AuxData array */
    size += auxDataArrayBytes;
    size += cmdLocBytes;
 
    /*
     * Compute the total number of bytes needed for this bytecode
     * including the storage for the Tcl objects in its object array.
     */
 
    objBytes = (numObjects * sizeof(Tcl_Obj));
    for (i = 0;  i < numObjects;  i++) {
        Tcl_Obj *litObjPtr = envPtr->objArrayPtr[i];
        if (litObjPtr->bytes != NULL) {
            objBytes += litObjPtr->length;
        }
    }
    totalSize = (size + objBytes);
 
#ifdef TCL_COMPILE_STATS
    tclNumCompilations++;
    tclTotalSourceBytes += (double) srcLen;
    tclTotalCodeBytes += (double) totalSize;
 
    tclTotalInstBytes += (double) codeBytes;
    tclTotalObjBytes += (double) objBytes;
    tclTotalExceptBytes += exceptArrayBytes;
    tclTotalAuxBytes += (double) auxDataArrayBytes;
    tclTotalCmdMapBytes += (double) cmdLocBytes;
 
    tclCurrentSourceBytes += (double) srcLen;
    tclCurrentCodeBytes += (double) totalSize;
 
    srcLenLog2 = TclLog2(srcLen);
    sizeLog2 = TclLog2((int) totalSize);
    if ((srcLenLog2 > 31) || (sizeLog2 > 31)) {
        panic("TclInitByteCodeObj: bad source or code sizes\n");
    }
    tclSourceCount[srcLenLog2]++;
    tclByteCodeCount[sizeLog2]++;
#endif /* TCL_COMPILE_STATS */    
 
    if (envPtr->iPtr->varFramePtr != NULL) {
        namespacePtr = envPtr->iPtr->varFramePtr->nsPtr;
    } else {
        namespacePtr = envPtr->iPtr->globalNsPtr;
    }
 
    p = (unsigned char *) ckalloc(size);
    codePtr = (ByteCode *) p;
    codePtr->iPtr = envPtr->iPtr;
    codePtr->compileEpoch = envPtr->iPtr->compileEpoch;
    codePtr->nsPtr = namespacePtr;
    codePtr->nsEpoch = namespacePtr->resolverEpoch;
    codePtr->refCount = 1;
    codePtr->flags = 0;
    codePtr->source = envPtr->source;
    codePtr->procPtr = envPtr->procPtr;
    codePtr->totalSize = totalSize;
    codePtr->numCommands = envPtr->numCommands;
    codePtr->numSrcChars = srcLen;
    codePtr->numCodeBytes = codeBytes;
    codePtr->numObjects = numObjects;
    codePtr->numExcRanges = envPtr->excRangeArrayNext;
    codePtr->numAuxDataItems = envPtr->auxDataArrayNext;
    codePtr->auxDataArrayPtr = NULL;
    codePtr->numCmdLocBytes = cmdLocBytes;
    codePtr->maxExcRangeDepth = envPtr->maxExcRangeDepth;
    codePtr->maxStackDepth = envPtr->maxStackDepth;
 
    p += sizeof(ByteCode);
    codePtr->codeStart = p;
    memcpy((VOID *) p, (VOID *) envPtr->codeStart, codeBytes);
 
    p += TCL_ALIGN(codeBytes);        /* align object array */
    codePtr->objArrayPtr = (Tcl_Obj **) p;
    memcpy((VOID *) p, (VOID *) envPtr->objArrayPtr, objArrayBytes);
 
    p += TCL_ALIGN(objArrayBytes);    /* align exception range array */
    if (exceptArrayBytes > 0) {
        codePtr->excRangeArrayPtr = (ExceptionRange *) p;
        memcpy((VOID *) p, (VOID *) envPtr->excRangeArrayPtr,
                exceptArrayBytes);
    }
 
    p += TCL_ALIGN(exceptArrayBytes); /* align AuxData array */
    if (auxDataArrayBytes > 0) {
        codePtr->auxDataArrayPtr = (AuxData *) p;
        memcpy((VOID *) p, (VOID *) envPtr->auxDataArrayPtr,
                auxDataArrayBytes);
    }
 
    p += auxDataArrayBytes;
    nextPtr = EncodeCmdLocMap(envPtr, codePtr, (unsigned char *) p);
    if (((size_t)(nextPtr - p)) != cmdLocBytes) {
        panic("TclInitByteCodeObj: encoded cmd location bytes %d != expected size %d\n", (nextPtr - p), cmdLocBytes);
    }
 
    /*
     * Free the old internal rep then convert the object to a
     * bytecode object by making its internal rep point to the just
     * compiled ByteCode.
     */
 
    if ((objPtr->typePtr != NULL) &&
            (objPtr->typePtr->freeIntRepProc != NULL)) {
        objPtr->typePtr->freeIntRepProc(objPtr);
    }
    objPtr->internalRep.otherValuePtr = (VOID *) codePtr;
    objPtr->typePtr = &tclByteCodeType;
}
 
/*
 *----------------------------------------------------------------------
 *
 * GetCmdLocEncodingSize --
 *
 *      Computes the total number of bytes needed to encode the command
 *      location information for some compiled code.
 *
 * Results:
 *      The byte count needed to encode the compiled location information.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
 
static int
GetCmdLocEncodingSize(envPtr)
     CompileEnv *envPtr;        /* Points to compilation environment
                                 * structure containing the CmdLocation
                                 * structure to encode. */
{
    register CmdLocation *mapPtr = envPtr->cmdMapPtr;
    int numCmds = envPtr->numCommands;
    int codeDelta, codeLen, srcDelta, srcLen;
    int codeDeltaNext, codeLengthNext, srcDeltaNext, srcLengthNext;
                                /* The offsets in their respective byte
                                 * sequences where the next encoded offset
                                 * or length should go. */
    int prevCodeOffset, prevSrcOffset, i;
 
    codeDeltaNext = codeLengthNext = srcDeltaNext = srcLengthNext = 0;
    prevCodeOffset = prevSrcOffset = 0;
    for (i = 0;  i < numCmds;  i++) {
        codeDelta = (mapPtr[i].codeOffset - prevCodeOffset);
        if (codeDelta < 0) {
            panic("GetCmdLocEncodingSize: bad code offset");
        } else if (codeDelta <= 127) {
            codeDeltaNext++;
        } else {
            codeDeltaNext += 5;  /* 1 byte for 0xFF, 4 for positive delta */
        }
        prevCodeOffset = mapPtr[i].codeOffset;
 
        codeLen = mapPtr[i].numCodeBytes;
        if (codeLen < 0) {
            panic("GetCmdLocEncodingSize: bad code length");
        } else if (codeLen <= 127) {
            codeLengthNext++;
        } else {
            codeLengthNext += 5; /* 1 byte for 0xFF, 4 for length */
        }
 
        srcDelta = (mapPtr[i].srcOffset - prevSrcOffset);
        if ((-127 <= srcDelta) && (srcDelta <= 127)) {
            srcDeltaNext++;
        } else {
            srcDeltaNext += 5;   /* 1 byte for 0xFF, 4 for delta */
        }
        prevSrcOffset = mapPtr[i].srcOffset;
 
        srcLen = mapPtr[i].numSrcChars;
        if (srcLen < 0) {
            panic("GetCmdLocEncodingSize: bad source length");
        } else if (srcLen <= 127) {
            srcLengthNext++;
        } else {
            srcLengthNext += 5;  /* 1 byte for 0xFF, 4 for length */
        }
    }
 
    return (codeDeltaNext + codeLengthNext + srcDeltaNext + srcLengthNext);
}
 
/*
 *----------------------------------------------------------------------
 *
 * EncodeCmdLocMap --
 *
 *      Encode the command location information for some compiled code into
 *      a ByteCode structure. The encoded command location map is stored as
 *      three adjacent byte sequences.
 *
 * Results:
 *      Pointer to the first byte after the encoded command location
 *      information.
 *
 * Side effects:
 *      The encoded information is stored into the block of memory headed
 *      by codePtr. Also records pointers to the start of the four byte
 *      sequences in fields in codePtr's ByteCode header structure.
 *
 *----------------------------------------------------------------------
 */
 
static unsigned char *
EncodeCmdLocMap(envPtr, codePtr, startPtr)
     CompileEnv *envPtr;        /* Points to compilation environment
                                 * structure containing the CmdLocation
                                 * structure to encode. */
     ByteCode *codePtr;         /* ByteCode in which to encode envPtr's
                                 * command location information. */
     unsigned char *startPtr;   /* Points to the first byte in codePtr's
                                 * memory block where the location
                                 * information is to be stored. */
{
    register CmdLocation *mapPtr = envPtr->cmdMapPtr;
    int numCmds = envPtr->numCommands;
    register unsigned char *p = startPtr;
    int codeDelta, codeLen, srcDelta, srcLen, prevOffset;
    register int i;
 
    /*
     * Encode the code offset for each command as a sequence of deltas.
     */
 
    codePtr->codeDeltaStart = p;
    prevOffset = 0;
    for (i = 0;  i < numCmds;  i++) {
        codeDelta = (mapPtr[i].codeOffset - prevOffset);
        if (codeDelta < 0) {
            panic("EncodeCmdLocMap: bad code offset");
        } else if (codeDelta <= 127) {
            TclStoreInt1AtPtr(codeDelta, p);
            p++;
        } else {
            TclStoreInt1AtPtr(0xFF, p);
            p++;
            TclStoreInt4AtPtr(codeDelta, p);
            p += 4;
        }
        prevOffset = mapPtr[i].codeOffset;
    }
 
    /*
     * Encode the code length for each command.
     */
 
    codePtr->codeLengthStart = p;
    for (i = 0;  i < numCmds;  i++) {
        codeLen = mapPtr[i].numCodeBytes;
        if (codeLen < 0) {
            panic("EncodeCmdLocMap: bad code length");
        } else if (codeLen <= 127) {
            TclStoreInt1AtPtr(codeLen, p);
            p++;
        } else {
            TclStoreInt1AtPtr(0xFF, p);
            p++;
            TclStoreInt4AtPtr(codeLen, p);
            p += 4;
        }
    }
 
    /*
     * Encode the source offset for each command as a sequence of deltas.
     */
 
    codePtr->srcDeltaStart = p;
    prevOffset = 0;
    for (i = 0;  i < numCmds;  i++) {
        srcDelta = (mapPtr[i].srcOffset - prevOffset);
        if ((-127 <= srcDelta) && (srcDelta <= 127)) {
            TclStoreInt1AtPtr(srcDelta, p);
            p++;
        } else {
            TclStoreInt1AtPtr(0xFF, p);
            p++;
            TclStoreInt4AtPtr(srcDelta, p);
            p += 4;
        }
        prevOffset = mapPtr[i].srcOffset;
    }
 
    /*
     * Encode the source length for each command.
     */
 
    codePtr->srcLengthStart = p;
    for (i = 0;  i < numCmds;  i++) {
        srcLen = mapPtr[i].numSrcChars;
        if (srcLen < 0) {
            panic("EncodeCmdLocMap: bad source length");
        } else if (srcLen <= 127) {
            TclStoreInt1AtPtr(srcLen, p);
            p++;
        } else {
            TclStoreInt1AtPtr(0xFF, p);
            p++;
            TclStoreInt4AtPtr(srcLen, p);
            p += 4;
        }
    }
 
    return p;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileString --
 *
 *      Compile a Tcl script in a null-terminated binary string.
 *
 * Results:
 *      The return value is TCL_OK on a successful compilation and TCL_ERROR
 *      on failure. If TCL_ERROR is returned, then the interpreter's result
 *      contains an error message.
 *
 *      envPtr->termOffset and interp->termOffset are filled in with the
 *      offset of the character in the string just after the last one
 *      successfully processed; this might be the offset of the ']' (if
 *      flags & TCL_BRACKET_TERM), or the offset of the '\0' at the end of
 *      the string. Also updates envPtr->maxStackDepth with the maximum
 *      number of stack elements needed to execute the string's commands.
 *
 * Side effects:
 *      Adds instructions to envPtr to evaluate the string at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileString(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    Interp *iPtr = (Interp *) interp;
    register char *src = string;/* Points to current source char. */
    register char c = *src;     /* The current char. */
    register int type;          /* Current char's CHAR_TYPE type. */
    char termChar = (char)((flags & TCL_BRACKET_TERM)? ']' : '\0');
                                /* Return when this character is found
                                 * (either ']' or '\0'). Zero means newlines
                                 * terminate cmds. */
    int isFirstCmd = 1;         /* 1 if compiling the first cmd. */
    char *cmdSrcStart = NULL;   /* Points to first non-blank char in each
                                 * command. Initialized to avoid compiler
                                 * warning. */
    int cmdIndex;               /* The index of the current command in the
                                 * compilation environment's command
                                 * location table. */
    int lastTopLevelCmdIndex = -1;
                                /* Index of most recent toplevel command in
                                 * the command location table. Initialized
                                 * to avoid compiler warning. */
    int cmdCodeOffset = -1;     /* Offset of first byte of current command's
                                 * code. Initialized to avoid compiler
                                 * warning. */
    int cmdWords;               /* Number of words in current command. */
    Tcl_Command cmd;            /* Used to search for commands. */
    Command *cmdPtr;            /* Points to command's Command structure if
                                 * first word is simple and command was
                                 * found; else NULL. */
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to execute all cmds. */
    char *termPtr;              /* Points to char that terminated word. */
    char savedChar;             /* Holds the character from string
                                 * termporarily replaced by a null character
                                 * during processing of words. */
    int objIndex = -1;          /* The object array index for a pushed
                                 * object holding a word or word part
                                 * Initialized to avoid compiler warning. */
    unsigned char *entryCodeNext = envPtr->codeNext;
                                /* Value of envPtr's current instruction
                                 * pointer at entry. Used to tell if any
                                 * instructions generated. */
    char *ellipsis = "";        /* Used to set errorInfo variable; "..."
                                 * indicates that not all of offending
                                 * command is included in errorInfo. ""
                                 * means that the command is all there. */
    Tcl_Obj *objPtr;
    int numChars;
    int result = TCL_OK;
    int savePushSimpleWords = envPtr->pushSimpleWords;
 
    /*
     * commands: command {(';' | '\n') command}
     */
 
    while ((src != lastChar) && (c != termChar)) {
        /*
         * Skip white space, semicolons, backslash-newlines (treated as
         * spaces), and comments before command.
         */
 
        type = CHAR_TYPE(src, lastChar);
        while ((type & (TCL_SPACE | TCL_BACKSLASH))
                || (c == '\n') || (c == ';')) {
            if (type == TCL_BACKSLASH) {
                if (src[1] == '\n') {
                    src += 2;
                } else {
                    break;
                }
            } else {
                src++;
            }
            c = *src;
            type = CHAR_TYPE(src, lastChar);
        }
 
        if (c == '#') {
            while (src != lastChar) {
                if (c == '\\') {
                    int numRead;
                    Tcl_Backslash(src, &numRead);
                    src += numRead;
                } else if (c == '\n') {
                    src++;
                    c = *src;
                    envPtr->termOffset = (src - string);
                    break;
                } else {
                    src++;
                }
                c = *src;
            }
            continue;   /* end of comment, restart outer command loop */
        }
 
        /*
         * Compile one command: zero or more words terminated by a '\n',
         * ';', ']' (if command is terminated by close bracket), or
         * the end of string.
         *
         * command: word*
         */
 
        type = CHAR_TYPE(src, lastChar);
        if ((type == TCL_COMMAND_END)
                && ((c != ']') || (flags & TCL_BRACKET_TERM))) {
            continue;  /* empty command; restart outer cmd loop */
        }
 
        /*
         * If not the first command, discard the previous command's result.
         */
 
        if (!isFirstCmd) {
            TclEmitOpcode(INST_POP, envPtr);
            if (!(flags & TCL_BRACKET_TERM)) {
                /*
                 * We are compiling a top level command. Update the number
                 * of code bytes for the last command to account for the pop
                 * instruction.
                 */
 
                (envPtr->cmdMapPtr[lastTopLevelCmdIndex]).numCodeBytes =
                    (envPtr->codeNext-envPtr->codeStart) - cmdCodeOffset;
            }
        }
 
        /*
         * Compile the words of the command. Process the first word
         * specially, since it is the name of a command. If it is a "simple"
         * string (just a sequence of characters), look it up in the table
         * of compilation procedures. If a word other than the first is
         * simple and represents an integer whose formatted representation
         * is the same as the word, just push an integer object. Also record
         * starting source and object information for the command.
         */
 
        envPtr->numCommands++;
        cmdIndex = (envPtr->numCommands - 1);
        if (!(flags & TCL_BRACKET_TERM)) {
            lastTopLevelCmdIndex = cmdIndex;
        }
 
        cmdSrcStart = src;
        cmdCodeOffset = (envPtr->codeNext - envPtr->codeStart);
        cmdWords = 0;
        EnterCmdStartData(envPtr, cmdIndex, src-envPtr->source,
                cmdCodeOffset);
 
        if ((!(flags & TCL_BRACKET_TERM))
                && (tclTraceCompile >= 1) && (envPtr->procPtr == NULL)) {
            /*
             * Display a line summarizing the top level command we are about
             * to compile.
             */
 
            char *p = cmdSrcStart;
            int numChars, complete;
 
            while ((CHAR_TYPE(p, lastChar) != TCL_COMMAND_END)
                   || ((*p == ']') && !(flags & TCL_BRACKET_TERM))) {
                p++;
            }
            numChars = (p - cmdSrcStart);
            complete = 1;
            if (numChars > 60) {
                numChars = 60;
                complete = 0;
            } else if ((numChars >= 2) && (*p == '\n') && (*(p-1) == '{')) {
                complete = 0;
            }
            fprintf(stdout, "Compiling: %.*s%s\n",
                    numChars, cmdSrcStart, (complete? "" : " ..."));
        }
 
        while ((type != TCL_COMMAND_END)
                || ((c == ']') && !(flags & TCL_BRACKET_TERM))) {
            /*
             * Skip any leading white space at the start of a word. Note
             * that a backslash-newline is treated as a space.
             */
 
            while (type & (TCL_SPACE | TCL_BACKSLASH)) {
                if (type == TCL_BACKSLASH) {
                    if (src[1] == '\n') {
                        src += 2;
                    } else {
                        break;
                    }
                } else {
                    src++;
                }
                c = *src;
                type = CHAR_TYPE(src, lastChar);
            }
            if ((type == TCL_COMMAND_END)
                    && ((c != ']') || (flags & TCL_BRACKET_TERM))) {
                break;          /* no words remain for command. */
            }
 
            /*
             * Compile one word. We use an inline version of CompileWord to
             * avoid an extra procedure call.
             */
 
            envPtr->pushSimpleWords = 0;
            if (type & (TCL_QUOTE | TCL_OPEN_BRACE)) {
                src++;
                if (type == TCL_QUOTE) {
                    result = TclCompileQuotes(interp, src, lastChar,
                            '"', flags, envPtr);
                } else {
                    result = CompileBraces(interp, src, lastChar,
                            flags, envPtr);
                }
                termPtr = (src + envPtr->termOffset);
                if (result != TCL_OK) {
                    src = termPtr;
                    goto done;
                }
 
                /*
                 * Make sure terminating character of the quoted or braced
                 * string is the end of word.
                 */
 
                c = *termPtr;
                if ((c == '\\') && (*(termPtr+1) == '\n')) {
                    /*
                     * Line is continued on next line; the backslash-
                     * newline turns into space, which terminates the word.
                     */
                } else {
                    type = CHAR_TYPE(termPtr, lastChar);
                    if ((type != TCL_SPACE) && (type != TCL_COMMAND_END)) {
                        Tcl_ResetResult(interp);
                        if (*(src-1) == '"') {
                            Tcl_AppendToObj(Tcl_GetObjResult(interp),
                                    "extra characters after close-quote", -1);
                        } else {
                            Tcl_AppendToObj(Tcl_GetObjResult(interp),
                                    "extra characters after close-brace", -1);
                        }
                        result = TCL_ERROR;
                    }
                }
            } else {
                result = CompileMultipartWord(interp, src, lastChar,
                        flags, envPtr);
                termPtr = (src + envPtr->termOffset);
            }
            if (result != TCL_OK) {
                ellipsis = "...";
                src = termPtr;
                goto done;
            }
 
            if (envPtr->wordIsSimple) {
                /*
                 * A simple word. Temporarily replace the terminating
                 * character with a null character.
                 */
 
                numChars = envPtr->numSimpleWordChars;
                savedChar = src[numChars];
                src[numChars] = '\0';
 
                if ((cmdWords == 0)
                        && (!(iPtr->flags & DONT_COMPILE_CMDS_INLINE))) {
                    /*
                     * The first word of a command and inline command
                     * compilation has not been disabled (e.g., by command
                     * traces). Look up the first word in the interpreter's
                     * hashtable of commands. If a compilation procedure is
                     * found, let it compile the command after resetting
                     * error logging information. Note that if we are
                     * compiling a procedure, we must look up the command
                     * in the procedure's namespace and not the current
                     * namespace.
                     */
 
                    Namespace *cmdNsPtr;
 
                    if (envPtr->procPtr != NULL) {
                        cmdNsPtr = envPtr->procPtr->cmdPtr->nsPtr;
                    } else {
                        cmdNsPtr = NULL;
                    }
 
                    cmdPtr = NULL;
                    cmd = Tcl_FindCommand(interp, src,
                            (Tcl_Namespace *) cmdNsPtr, /*flags*/ 0);
                    if (cmd != (Tcl_Command) NULL) {
                        cmdPtr = (Command *) cmd;
                    }
                    if ((cmdPtr != NULL) && (cmdPtr->compileProc != NULL)) {
                        char *firstArg = termPtr;
                        src[numChars] = savedChar;
                        iPtr->flags &= ~(ERR_ALREADY_LOGGED | ERR_IN_PROGRESS
                                         | ERROR_CODE_SET);
                        result = (*(cmdPtr->compileProc))(interp,
                                firstArg, lastChar, flags, envPtr);
                        if (result == TCL_OK) {
                            src = (firstArg + envPtr->termOffset);
                            maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
                            goto finishCommand;
                        } else if (result == TCL_OUT_LINE_COMPILE) {
                            result = TCL_OK;
                            src[numChars] = '\0';
                        } else {
                            src = firstArg;
                            goto done;           /* an error */
                        }
                    }
 
                    /*
                     * No compile procedure was found for the command: push
                     * the word and continue to compile the remaining
                     * words. If a hashtable entry was found for the
                     * command, push a CmdName object instead to avoid
                     * runtime lookups. If necessary, convert the pushed
                     * object to be a CmdName object. If this is the first
                     * CmdName object in this code unit that refers to the
                     * command, increment the reference count in the
                     * Command structure to reflect the new reference from
                     * the CmdName object and, if the command is deleted
                     * later, to keep the Command structure from being freed
                     * until TclExecuteByteCode has a chance to recognize
                     * that the command was deleted.
                     */
 
                    objIndex = TclObjIndexForString(src, numChars,
                            /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
                    if (cmdPtr != NULL) {
                        objPtr = envPtr->objArrayPtr[objIndex];
                        if ((objPtr->typePtr != &tclCmdNameType)
                                && (objPtr->bytes != NULL)) {
                            ResolvedCmdName *resPtr = (ResolvedCmdName *)
                                    ckalloc(sizeof(ResolvedCmdName));
                            Namespace *nsPtr = (Namespace *)
                                    Tcl_GetCurrentNamespace(interp);
 
                            resPtr->cmdPtr = cmdPtr;
                            resPtr->refNsPtr = nsPtr;
                            resPtr->refNsId = nsPtr->nsId;
                            resPtr->refNsCmdEpoch = nsPtr->cmdRefEpoch;
                            resPtr->cmdEpoch = cmdPtr->cmdEpoch;
                            resPtr->refCount = 1;
                            objPtr->internalRep.twoPtrValue.ptr1 =
                                (VOID *) resPtr;
                            objPtr->internalRep.twoPtrValue.ptr2 = NULL;
                            objPtr->typePtr = &tclCmdNameType;
                            cmdPtr->refCount++;
                        }
                    }
                } else {
                    /*
                     * See if the word represents an integer whose formatted
                     * representation is the same as the word (e.g., this is
                     * true for 123 and -1 but not for 00005). If so, just
                     * push an integer object.
                     */
 
                    int isCompilableInt = 0;
                    long n;
                    char buf[40];
 
                    if (TclLooksLikeInt(src)) {
                        int code = TclGetLong(interp, src, &n);
                        if (code == TCL_OK) {
                            TclFormatInt(buf, n);
                            if (strcmp(src, buf) == 0) {
                                isCompilableInt = 1;
                                objIndex = TclObjIndexForString(src,
                                        numChars, /*allocStrRep*/ 0,
                                        /*inHeap*/ 0, envPtr);
                                objPtr = envPtr->objArrayPtr[objIndex];
 
                                Tcl_InvalidateStringRep(objPtr);
                                objPtr->internalRep.longValue = n;
                                objPtr->typePtr = &tclIntType;
                            }
                        } else {
                            Tcl_ResetResult(interp);
                        }
                    }
                    if (!isCompilableInt) {
                        objIndex = TclObjIndexForString(src, numChars,
                                /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
                    }
                }
                src[numChars] = savedChar;
                TclEmitPush(objIndex, envPtr);
                maxDepth = TclMax((cmdWords + 1), maxDepth);
            } else {            /* not a simple word */
                maxDepth = TclMax((cmdWords + envPtr->maxStackDepth),
                               maxDepth);
            }
            src = termPtr;
            c = *src;
            type = CHAR_TYPE(src, lastChar);
            cmdWords++;
        }
 
        /*
         * Emit an invoke instruction for the command. If a compile command
         * was found for the command we called it and skipped this.
         */
 
        if (cmdWords > 0) {
            if (cmdWords <= 255) {
                TclEmitInstUInt1(INST_INVOKE_STK1, cmdWords, envPtr);
            } else {
                TclEmitInstUInt4(INST_INVOKE_STK4, cmdWords, envPtr);
            }
        }
 
        /*
         * Update the compilation environment structure. Record
         * source/object information for the command.
         */
 
        finishCommand:
        EnterCmdExtentData(envPtr, cmdIndex, src-cmdSrcStart,
                (envPtr->codeNext-envPtr->codeStart) - cmdCodeOffset);
 
        isFirstCmd = 0;
        envPtr->termOffset = (src - string);
        c = *src;
    }
 
    done:
    if (result == TCL_OK) {
        /*
         * If the source string yielded no instructions (e.g., if it was
         * empty), push an empty string object as the command's result.
         */
 
        if (entryCodeNext == envPtr->codeNext) {
            int objIndex = TclObjIndexForString("", 0, /*allocStrRep*/ 0,
                                                /*inHeap*/ 0, envPtr);
            TclEmitPush(objIndex, envPtr);
            maxDepth = 1;
        }
    } else {
        /*
         * Add additional error information. First compute the line number
         * where the error occurred.
         */
 
        register char *p;
        int numChars;
        char buf[200];
 
        iPtr->errorLine = 1;
        for (p = string;  p != cmdSrcStart;  p++) {
            if (*p == '\n') {
                iPtr->errorLine++;
            }
        }
        for (  ; isspace(UCHAR(*p)) || (*p == ';');  p++) {
            if (*p == '\n') {
                iPtr->errorLine++;
            }
        }
 
        /*
         * Figure out how much of the command to print (up to a certain
         * number of characters, or up to the end of the command).
         */
 
        p = cmdSrcStart;
        while ((CHAR_TYPE(p, lastChar) != TCL_COMMAND_END)
                || ((*p == ']') && !(flags & TCL_BRACKET_TERM))) {
            p++;
        }
        numChars = (p - cmdSrcStart);
        if (numChars > 150) {
            numChars = 150;
            ellipsis = " ...";
        } else if ((numChars >= 2) && (*p == '\n') && (*(p-1) == '{')) {
            ellipsis = " ...";
        }
 
        sprintf(buf, "\n    while compiling\n\"%.*s%s\"",
                numChars, cmdSrcStart, ellipsis);
        Tcl_AddObjErrorInfo(interp, buf, -1);
    }
 
    envPtr->termOffset = (src - string);
    iPtr->termOffset = envPtr->termOffset;
    envPtr->maxStackDepth = maxDepth;
    envPtr->pushSimpleWords = savePushSimpleWords;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * CompileWord --
 *
 *      This procedure compiles one word from a command string. It skips
 *      any leading white space.
 *
 *      Ordinarily, callers set envPtr->pushSimpleWords to 1 and this
 *      procedure emits push and other instructions to compute the
 *      word on the Tcl evaluation stack at execution time. If a caller sets
 *      envPtr->pushSimpleWords to 0, CompileWord will _not_ compile
 *      "simple" words: words that are just a sequence of characters without
 *      backslashes. It will leave their compilation up to the caller.
 *
 *      As an important special case, if the word is simple, this procedure
 *      sets envPtr->wordIsSimple to 1 and envPtr->numSimpleWordChars to the
 *      number of characters in the simple word. This allows the caller to
 *      process these words specially.
 *
 * Results:
 *      The return value is a standard Tcl result. If an error occurs, an
 *      error message is left in the interpreter's result.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed in the last
 *      word. This is normally the character just after the last one in a
 *      word (perhaps the command terminator), or the vicinity of an error
 *      (if the result is not TCL_OK).
 *
 *      envPtr->wordIsSimple is set 1 if the word is simple: just a
 *      sequence of characters without backslashes. If so, the word's
 *      characters are the envPtr->numSimpleWordChars characters starting
 *      at string.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to evaluate the word. This is not changed if
 *      the word is simple and envPtr->pushSimpleWords was 0 (false).
 *
 * Side effects:
 *      Instructions are added to envPtr to compute and push the word
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
static int
CompileWord(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Interpreter to use for nested command
                                 * evaluations and error messages. */
    char *string;               /* First character of word. */
    char *lastChar;              /* Pointer to terminating character of
                                  * string. */
    int flags;                  /* Flags to control compilation (same values
                                 * passed to Tcl_EvalObj). */
    CompileEnv *envPtr;         /* Holds the resulting instructions. */
{
    /*
     * Compile one word: approximately
     *
     * word:             quoted_string | braced_string | multipart_word
     * quoted_string:    '"' char* '"'
     * braced_string:    '{' char* '}'
     * multipart_word    (see CompileMultipartWord below)
     */
 
    register char *src = string; /* Points to current source char. */
    register int type = CHAR_TYPE(src, lastChar);
                                 /* Current char's CHAR_TYPE type. */
    int maxDepth = 0;             /* Maximum number of stack elements needed
                                  * to compute and push the word. */
    char *termPtr = src;         /* Points to the character that terminated
                                  * the word. */
    int result = TCL_OK;
 
    /*
     * Skip any leading white space at the start of a word. Note that a
     * backslash-newline is treated as a space.
     */
 
    while (type & (TCL_SPACE | TCL_BACKSLASH)) {
        if (type == TCL_BACKSLASH) {
            if (src[1] == '\n') {
                src += 2;
            } else {
                break;          /* no longer white space */
            }
        } else {
            src++;
        }
        type = CHAR_TYPE(src, lastChar);
    }
    if (type == TCL_COMMAND_END) {
        goto done;
    }
 
    /*
     * Compile the word. Handle quoted and braced string words here in order
     * to avoid an extra procedure call.
     */
 
    if (type & (TCL_QUOTE | TCL_OPEN_BRACE)) {
        src++;
        if (type == TCL_QUOTE) {
            result = TclCompileQuotes(interp, src, lastChar, '"', flags,
                    envPtr);
        } else {
            result = CompileBraces(interp, src, lastChar, flags, envPtr);
        }
        termPtr = (src + envPtr->termOffset);
        if (result != TCL_OK) {
            goto done;
        }
 
        /*
         * Make sure terminating character of the quoted or braced string is
         * the end of word.
         */
 
        if ((*termPtr == '\\') && (*(termPtr+1) == '\n')) {
            /*
             * Line is continued on next line; the backslash-newline turns
             * into space, which terminates the word.
             */
        } else {
            type = CHAR_TYPE(termPtr, lastChar);
            if (!(type & (TCL_SPACE | TCL_COMMAND_END))) {
                Tcl_ResetResult(interp);
                if (*(src-1) == '"') {
                    Tcl_AppendToObj(Tcl_GetObjResult(interp),
                            "extra characters after close-quote", -1);
                } else {
                    Tcl_AppendToObj(Tcl_GetObjResult(interp),
                            "extra characters after close-brace", -1);
                }
                result = TCL_ERROR;
                goto done;
            }
        }
        maxDepth = envPtr->maxStackDepth;
    } else {
        result = CompileMultipartWord(interp, src, lastChar, flags, envPtr);
        termPtr = (src + envPtr->termOffset);
        maxDepth = envPtr->maxStackDepth;
    }
 
    /*
     * Done processing the word. The values of envPtr->wordIsSimple and
     * envPtr->numSimpleWordChars are left at the values returned by
     * TclCompileQuotes/Braces/MultipartWord.
     */
 
    done:
    envPtr->termOffset = (termPtr - string);
    envPtr->maxStackDepth = maxDepth;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * CompileMultipartWord --
 *
 *      This procedure compiles one multipart word: a word comprised of some
 *      number of nested commands, variable references, or arbitrary
 *      characters. This procedure assumes that quoted string and braced
 *      string words and the end of command have already been handled by its
 *      caller. It also assumes that any leading white space has already
 *      been consumed.
 *
 *      Ordinarily, callers set envPtr->pushSimpleWords to 1 and this
 *      procedure emits push and other instructions to compute the word on
 *      the Tcl evaluation stack at execution time. If a caller sets
 *      envPtr->pushSimpleWords to 0, it will _not_ compile "simple" words:
 *      words that are just a sequence of characters without backslashes.
 *      It will leave their compilation up to the caller. This is done, for
 *      example, to provide special support for the first word of commands,
 *      which are almost always the (simple) name of a command.
 *
 *      As an important special case, if the word is simple, this procedure
 *      sets envPtr->wordIsSimple to 1 and envPtr->numSimpleWordChars to the
 *      number of characters in the simple word. This allows the caller to
 *      process these words specially.
 *
 * Results:
 *      The return value is a standard Tcl result. If an error occurs, an
 *      error message is left in the interpreter's result.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed in the last
 *      word. This is normally the character just after the last one in a
 *      word (perhaps the command terminator), or the vicinity of an error
 *      (if the result is not TCL_OK).
 *
 *      envPtr->wordIsSimple is set 1 if the word is simple: just a
 *      sequence of characters without backslashes. If so, the word's
 *      characters are the envPtr->numSimpleWordChars characters starting
 *      at string.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to evaluate the word. This is not changed if
 *      the word is simple and envPtr->pushSimpleWords was 0 (false).
 *
 * Side effects:
 *      Instructions are added to envPtr to compute and push the word
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
static int
CompileMultipartWord(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Interpreter to use for nested command
                                 * evaluations and error messages. */
    char *string;               /* First character of word. */
    char *lastChar;              /* Pointer to terminating character of
                                  * string. */
    int flags;                  /* Flags to control compilation (same values
                                 * passed to Tcl_EvalObj). */
    CompileEnv *envPtr;         /* Holds the resulting instructions. */
{
    /*
     * Compile one multi_part word:
     *
     * multi_part_word:  word_part+
     * word_part:        nested_cmd | var_reference | char+
     * nested_cmd:       '[' command ']'
     * var_reference:    '$' name | '$' name '(' index_string ')' |
     *                   '$' '{' braced_name '}')
     * name:             (letter | digit | underscore)+
     * braced_name:      (non_close_brace_char)*
     * index_string:     (non_close_paren_char)*
     */
 
    register char *src = string; /* Points to current source char. */
    register char c = *src;     /* The current char. */
    register int type;          /* Current char's CHAR_TYPE type. */
    int bracketNormal = !(flags & TCL_BRACKET_TERM);
    int simpleWord = 0;          /* Set 1 if word is simple. */
    int numParts = 0;            /* Count of word_part objs pushed. */
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to compute and push the word. */
    char *start;                /* Starting position of char+ word_part. */
    int hasBackslash;           /* Nonzero if '\' in char+ word_part. */
    int numChars;               /* Number of chars in char+ word_part. */
    char savedChar;             /* Holds the character from string
                                 * termporarily replaced by a null character
                                 * during word_part processing. */
    int objIndex;               /* The object array index for a pushed
                                 * object holding a word_part. */
    int savePushSimpleWords = envPtr->pushSimpleWords;
    int result = TCL_OK;
    int numRead;
 
    type = CHAR_TYPE(src, lastChar);
    while (1) {
        /*
         * Process a word_part: a sequence of chars, a var reference, or
         * a nested command.
         */
 
        if ((type & (TCL_NORMAL | TCL_CLOSE_BRACE | TCL_BACKSLASH |
                     TCL_QUOTE | TCL_OPEN_BRACE)) ||
            ((c == ']') && bracketNormal)) {
            /*
             * A char+ word part. Scan first looking for any backslashes.
             * Note that a backslash-newline must be treated as a word
             * separator, as if the backslash-newline had been collapsed
             * before command parsing began.
             */
 
            start = src;
            hasBackslash = 0;
            do {
                if (type == TCL_BACKSLASH) {
                    hasBackslash = 1;
                    Tcl_Backslash(src, &numRead);
                    if (src[1] == '\n') {
                        src += numRead;
                        type = TCL_SPACE; /* force word end */
                        break;
                    }
                    src += numRead;
                } else {
                    src++;
                }
                c = *src;
                type = CHAR_TYPE(src, lastChar);
            } while (type & (TCL_NORMAL | TCL_BACKSLASH | TCL_QUOTE |
                            TCL_OPEN_BRACE | TCL_CLOSE_BRACE)
                            || ((c == ']') && bracketNormal));
 
            if ((numParts == 0) && !hasBackslash
                    && (type & (TCL_SPACE | TCL_COMMAND_END))) {
                /*
                 * The word is "simple": just a sequence of characters
                 * without backslashes terminated by a TCL_SPACE or
                 * TCL_COMMAND_END. Just return if we are not to compile
                 * simple words.
                 */
 
                simpleWord = 1;
                if (!envPtr->pushSimpleWords) {
                    envPtr->wordIsSimple = 1;
                    envPtr->numSimpleWordChars = (src - string);
                    envPtr->termOffset = envPtr->numSimpleWordChars;
                    envPtr->pushSimpleWords = savePushSimpleWords;
                    return TCL_OK;
                }
            }
 
            /*
             * Create and push a string object for the char+ word_part,
             * which starts at "start" and ends at the char just before
             * src. If backslashes were found, copy the word_part's
             * characters with substituted backslashes into a heap-allocated
             * buffer and use it to create the string object. Temporarily
             * replace the terminating character with a null character.
             */
 
            numChars = (src - start);
            savedChar = start[numChars];
            start[numChars] = '\0';
            if ((numChars > 0) && (hasBackslash)) {
                char *buffer = ckalloc((unsigned) numChars + 1);
                register char *dst = buffer;
                register char *p = start;
                while (p < src) {
                    if (*p == '\\') {
                        *dst = Tcl_Backslash(p, &numRead);
                        if (p[1] == '\n') {
                            break;
                        }
                        p += numRead;
                        dst++;
                    } else {
                        *dst++ = *p++;
                    }
                }
                *dst = '\0';
                objIndex = TclObjIndexForString(buffer, dst-buffer,
                        /*allocStrRep*/ 1, /*inHeap*/ 1, envPtr);
            } else {
                objIndex = TclObjIndexForString(start, numChars,
                        /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
            }
            start[numChars] = savedChar;
            TclEmitPush(objIndex, envPtr);
            maxDepth = TclMax((numParts + 1), maxDepth);
        } else if (type == TCL_DOLLAR) {
            result = TclCompileDollarVar(interp, src, lastChar,
                    flags, envPtr);
            src += envPtr->termOffset;
            if (result != TCL_OK) {
                goto done;
            }
            maxDepth = TclMax((numParts + envPtr->maxStackDepth), maxDepth);
            c = *src;
            type = CHAR_TYPE(src, lastChar);
        } else if (type == TCL_OPEN_BRACKET) {
            char *termPtr;
            envPtr->pushSimpleWords = 1;
            src++;
            result = TclCompileString(interp, src, lastChar,
                                      (flags | TCL_BRACKET_TERM), envPtr);
            termPtr = (src + envPtr->termOffset);
            if (*termPtr == ']') {
                termPtr++;
            } else if (*termPtr == '\0') {
                /*
                 * Missing ] at end of nested command.
                 */
 
                Tcl_ResetResult(interp);
                Tcl_AppendToObj(Tcl_GetObjResult(interp),
                        "missing close-bracket", -1);
                result = TCL_ERROR;
            }
            src = termPtr;
            if (result != TCL_OK) {
                goto done;
            }
            maxDepth = TclMax((numParts + envPtr->maxStackDepth), maxDepth);
            c = *src;
            type = CHAR_TYPE(src, lastChar);
        } else if (type & (TCL_SPACE | TCL_COMMAND_END)) {
            goto wordEnd;
        }
        numParts++;
    } /* end of infinite loop */
 
    wordEnd:
    /*
     * End of a non-simple word: TCL_SPACE, TCL_COMMAND_END, or
     * backslash-newline. Concatenate the word_parts if necessary.
     */
 
    while (numParts > 255) {
        TclEmitInstUInt1(INST_CONCAT1, 255, envPtr);
        numParts -= 254;  /* concat pushes 1 obj, the result */
    }
    if (numParts > 1) {
        TclEmitInstUInt1(INST_CONCAT1, numParts, envPtr);
    }
 
    done:
    if (simpleWord) {
        envPtr->wordIsSimple = 1;
        envPtr->numSimpleWordChars = (src - string);
    } else {
        envPtr->wordIsSimple = 0;
        envPtr->numSimpleWordChars = 0;
    }
    envPtr->termOffset = (src - string);
    envPtr->maxStackDepth = maxDepth;
    envPtr->pushSimpleWords = savePushSimpleWords;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileQuotes --
 *
 *      This procedure compiles a double-quoted string such as a quoted Tcl
 *      command argument or a quoted value in a Tcl expression. This
 *      procedure is also used to compile array element names within
 *      parentheses (where the termChar will be ')' instead of '"'), or
 *      anything else that needs the substitutions that happen in quotes.
 *
 *      Ordinarily, callers set envPtr->pushSimpleWords to 1 and
 *      TclCompileQuotes always emits push and other instructions to compute
 *      the word on the Tcl evaluation stack at execution time. If a caller
 *      sets envPtr->pushSimpleWords to 0, TclCompileQuotes will not compile
 *      "simple" words: words that are just a sequence of characters without
 *      backslashes. It will leave their compilation up to the caller. This
 *      is done to provide special support for the first word of commands,
 *      which are almost always the (simple) name of a command.
 *
 *      As an important special case, if the word is simple, this procedure
 *      sets envPtr->wordIsSimple to 1 and envPtr->numSimpleWordChars to the
 *      number of characters in the simple word. This allows the caller to
 *      process these words specially.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK unless
 *      there was an error while parsing the quoted string. If an error
 *      occurs then the interpreter's result contains a standard error
 *      message.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed; this is
 *      usually the character just after the matching close-quote.
 *
 *      envPtr->wordIsSimple is set 1 if the word is simple: just a
 *      sequence of characters without backslashes. If so, the word's
 *      characters are the envPtr->numSimpleWordChars characters starting
 *      at string.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to evaluate the word. This is not changed if
 *      the word is simple and envPtr->pushSimpleWords was 0 (false).
 *
 * Side effects:
 *      Instructions are added to envPtr to push the quoted-string
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileQuotes(interp, string, lastChar, termChar, flags, envPtr)
    Tcl_Interp *interp;          /* Interpreter to use for nested command
                                  * evaluations and error messages. */
    char *string;                /* Points to the character just after
                                  * the opening '"' or '('. */
    char *lastChar;              /* Pointer to terminating character of
                                  * string. */
    int termChar;                /* Character that terminates the "quoted"
                                  * string (usually double-quote, but might
                                  * be right-paren or something else). */
    int flags;                   /* Flags to control compilation (same
                                  * values passed to Tcl_Eval). */
    CompileEnv *envPtr;          /* Holds the resulting instructions. */
{
    register char *src = string; /* Points to current source char. */
    register char c = *src;      /* The current char. */
    int simpleWord = 0;           /* Set 1 if a simple quoted string word. */
    char *start;                 /* Start position of char+ string_part. */
    int hasBackslash;            /* 1 if '\' found in char+ string_part. */
    int numRead;                 /* Count of chars read by Tcl_Backslash. */
    int numParts = 0;             /* Count of string_part objs pushed. */
    int maxDepth = 0;             /* Maximum number of stack elements needed
                                  * to compute and push the string. */
    char savedChar;              /* Holds the character from string
                                  * termporarily replaced by a null
                                  * char during string_part processing. */
    int objIndex;                /* The object array index for a pushed
                                  * object holding a string_part. */
    int numChars;                /* Number of chars in string_part. */
    int savePushSimpleWords = envPtr->pushSimpleWords;
    int result = TCL_OK;
 
    /*
     * quoted_string: '"' string_part* '"'   (or termChar instead of ")
     * string_part:   var_reference | nested_cmd | char+
     */
 
 
    while ((src != lastChar) && (c != termChar)) {
        if (c == '$') {
            result = TclCompileDollarVar(interp, src, lastChar, flags,
                    envPtr);
            src += envPtr->termOffset;
            if (result != TCL_OK) {
                goto done;
            }
            maxDepth = TclMax((numParts + envPtr->maxStackDepth), maxDepth);
            c = *src;
        } else if (c == '[') {
            char *termPtr;
            envPtr->pushSimpleWords = 1;
            src++;
            result = TclCompileString(interp, src, lastChar,
                                      (flags | TCL_BRACKET_TERM), envPtr);
            termPtr = (src + envPtr->termOffset);
            if (*termPtr == ']') {
                termPtr++;
            }
            src = termPtr;
            if (result != TCL_OK) {
                goto done;
            }
            if (termPtr == lastChar) {
                /*
                 * Missing ] at end of nested command.
                 */
 
                Tcl_ResetResult(interp);
                Tcl_AppendToObj(Tcl_GetObjResult(interp),
                        "missing close-bracket", -1);
                result = TCL_ERROR;
                goto done;
            }
            maxDepth = TclMax((numParts + envPtr->maxStackDepth), maxDepth);
            c = *src;
        } else {
            /*
             * Start of a char+ string_part. Scan first looking for any
             * backslashes.
             */
 
            start = src;
            hasBackslash = 0;
            do {
                if (c == '\\') {
                    hasBackslash = 1;
                    Tcl_Backslash(src, &numRead);
                    src += numRead;
                } else {
                    src++;
                }
                c = *src;
            } while ((src != lastChar) && (c != '$') && (c != '[')
                    && (c != termChar));
 
            if ((numParts == 0) && !hasBackslash
                    && ((src == lastChar) && (c == termChar))) {
                /*
                 * The quoted string is "simple": just a sequence of
                 * characters without backslashes terminated by termChar or
                 * a null character. Just return if we are not to compile
                 * simple words.
                 */
 
                simpleWord = 1;
                if (!envPtr->pushSimpleWords) {
                    if ((src == lastChar) && (termChar != '\0')) {
                        char buf[40];
                        sprintf(buf, "missing %c", termChar);
                        Tcl_ResetResult(interp);
                        Tcl_AppendToObj(Tcl_GetObjResult(interp), buf, -1);
                        result = TCL_ERROR;
                    } else {
                        src++;
                    }
                    envPtr->wordIsSimple = 1;
                    envPtr->numSimpleWordChars = (src - string - 1);
                    envPtr->termOffset = (src - string);
                    envPtr->pushSimpleWords = savePushSimpleWords;
                    return result;
                }
            }
 
            /*
             * Create and push a string object for the char+ string_part
             * that starts at "start" and ends at the char just before
             * src. If backslashes were found, copy the string_part's
             * characters with substituted backslashes into a heap-allocated
             * buffer and use it to create the string object. Temporarily
             * replace the terminating character with a null character.
             */
 
            numChars = (src - start);
            savedChar = start[numChars];
            start[numChars] = '\0';
            if ((numChars > 0) && (hasBackslash)) {
                char *buffer = ckalloc((unsigned) numChars + 1);
                register char *dst = buffer;
                register char *p = start;
                while (p < src) {
                    if (*p == '\\') {
                        *dst++ = Tcl_Backslash(p, &numRead);
                        p += numRead;
                    } else {
                        *dst++ = *p++;
                    }
                }
                *dst = '\0';
                objIndex = TclObjIndexForString(buffer, (dst - buffer),
                        /*allocStrRep*/ 1, /*inHeap*/ 1, envPtr);
            } else {
                objIndex = TclObjIndexForString(start, numChars,
                        /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
            }
            start[numChars] = savedChar;
            TclEmitPush(objIndex, envPtr);
            maxDepth = TclMax((numParts + 1), maxDepth);
        }
        numParts++;
    }
 
    /*
     * End of the quoted string: src points at termChar or '\0'. If
     * necessary, concatenate the string_part objects on the stack.
     */
 
    if ((src == lastChar) && (termChar != '\0')) {
        char buf[40];
        sprintf(buf, "missing %c", termChar);
        Tcl_ResetResult(interp);
        Tcl_AppendToObj(Tcl_GetObjResult(interp), buf, -1);
        result = TCL_ERROR;
        goto done;
    } else {
        src++;
    }
 
    if (numParts == 0) {
        /*
         * The quoted string was empty. Push an empty string object.
         */
 
        int objIndex = TclObjIndexForString("", 0, /*allocStrRep*/ 0,
                                            /*inHeap*/ 0, envPtr);
        TclEmitPush(objIndex, envPtr);
    } else {
        /*
         * Emit any needed concat instructions.
         */
 
        while (numParts > 255) {
            TclEmitInstUInt1(INST_CONCAT1, 255, envPtr);
            numParts -= 254;  /* concat pushes 1 obj, the result */
        }
        if (numParts > 1) {
            TclEmitInstUInt1(INST_CONCAT1, numParts, envPtr);
        }
    }
 
    done:
    if (simpleWord) {
        envPtr->wordIsSimple = 1;
        envPtr->numSimpleWordChars = (src - string - 1);
    } else {
        envPtr->wordIsSimple = 0;
        envPtr->numSimpleWordChars = 0;
    }
    envPtr->termOffset = (src - string);
    envPtr->maxStackDepth = maxDepth;
    envPtr->pushSimpleWords = savePushSimpleWords;
    return result;
}
 
/*
 *--------------------------------------------------------------
 *
 * CompileBraces --
 *
 *      This procedure compiles characters between matching curly braces.
 *
 *      Ordinarily, callers set envPtr->pushSimpleWords to 1 and
 *      CompileBraces always emits a push instruction to compute the word on
 *      the Tcl evaluation stack at execution time. However, if a caller
 *      sets envPtr->pushSimpleWords to 0, CompileBraces will _not_ compile
 *      "simple" words: words that are just a sequence of characters without
 *      backslash-newlines. It will leave their compilation up to the
 *      caller.
 *
 *      As an important special case, if the word is simple, this procedure
 *      sets envPtr->wordIsSimple to 1 and envPtr->numSimpleWordChars to the
 *      number of characters in the simple word. This allows the caller to
 *      process these words specially.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK unless
 *      there was an error while parsing string. If an error occurs then
 *      the interpreter's result contains a standard error message.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed. This is
 *      usually the character just after the matching close-brace.
 *
 *      envPtr->wordIsSimple is set 1 if the word is simple: just a
 *      sequence of characters without backslash-newlines. If so, the word's
 *      characters are the envPtr->numSimpleWordChars characters starting
 *      at string.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to evaluate the word. This is not changed if
 *      the word is simple and envPtr->pushSimpleWords was 0 (false).
 *
 * Side effects:
 *      Instructions are added to envPtr to push the braced string
 *      at runtime.
 *
 *--------------------------------------------------------------
 */
 
static int
CompileBraces(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;          /* Interpreter to use for nested command
                                  * evaluations and error messages. */
    char *string;                /* Character just after opening bracket. */
    char *lastChar;              /* Pointer to terminating character of
                                  * string. */
    int flags;                   /* Flags to control compilation (same
                                  * values passed to Tcl_Eval). */
    CompileEnv *envPtr;          /* Holds the resulting instructions. */
{
    register char *src = string; /* Points to current source char. */
    register char c;             /* The current char. */
    int simpleWord = 0;           /* Set 1 if a simple braced string word. */
    int level = 1;               /* {} nesting level. Initially 1 since {
                                  * was parsed before we were called. */
    int hasBackslashNewline = 0; /* Nonzero if '\' found. */
    char *last;                  /* Points just before terminating '}'. */
    int numChars;                /* Number of chars in braced string. */
    char savedChar;              /* Holds the character from string
                                  * termporarily replaced by a null
                                  * char during braced string processing. */
    int objIndex;                /* The object array index for a pushed
                                  * object holding a braced string. */
    int numRead;
    int result = TCL_OK;
 
    /*
     * Check for any backslash-newlines, since we must treat
     * backslash-newlines specially (they must be replaced by spaces).
     */
 
    while (1) {
        c = *src;
        if (src == lastChar) {
            Tcl_ResetResult(interp);
            Tcl_AppendToObj(Tcl_GetObjResult(interp),
                    "missing close-brace", -1);
            result = TCL_ERROR;
            goto done;
        }
        if (CHAR_TYPE(src, lastChar) != TCL_NORMAL) {
            if (c == '{') {
                level++;
            } else if (c == '}') {
                --level;
                if (level == 0) {
                    src++;
                    last = (src - 2); /* point just before terminating } */
                    break;
                }
            } else if (c == '\\') {
                if (*(src+1) == '\n') {
                    hasBackslashNewline = 1;
                }
                (void) Tcl_Backslash(src, &numRead);
                src += numRead - 1;
            }
        }
        src++;
    }
 
    if (!hasBackslashNewline) {
        /*
         * The braced word is "simple": just a sequence of characters
         * without backslash-newlines. Just return if we are not to compile
         * simple words.
         */
 
        simpleWord = 1;
        if (!envPtr->pushSimpleWords) {
            envPtr->wordIsSimple = 1;
            envPtr->numSimpleWordChars = (src - string - 1);
            envPtr->termOffset = (src - string);
            return TCL_OK;
        }
    }
 
    /*
     * Create and push a string object for the braced string. This starts at
     * "string" and ends just after "last" (which points to the final
     * character before the terminating '}'). If backslash-newlines were
     * found, we copy characters one at a time into a heap-allocated buffer
     * and do backslash-newline substitutions.
     */
 
    numChars = (last - string + 1);
    savedChar = string[numChars];
    string[numChars] = '\0';
    if ((numChars > 0) && (hasBackslashNewline)) {
        char *buffer = ckalloc((unsigned) numChars + 1);
        register char *dst = buffer;
        register char *p = string;
        while (p <= last) {
            c = *dst++ = *p++;
            if (c == '\\') {
                if (*p == '\n') {
                    dst[-1] = Tcl_Backslash(p-1, &numRead);
                    p += numRead - 1;
                } else {
                    (void) Tcl_Backslash(p-1, &numRead);
                    while (numRead > 1) {
                        *dst++ = *p++;
                        numRead--;
                    }
                }
            }
        }
        *dst = '\0';
        objIndex = TclObjIndexForString(buffer, (dst - buffer),
                /*allocStrRep*/ 1, /*inHeap*/ 1, envPtr);
    } else {
        objIndex = TclObjIndexForString(string, numChars, /*allocStrRep*/ 1,
                                        /*inHeap*/ 0, envPtr);
    }
    string[numChars] = savedChar;
    TclEmitPush(objIndex, envPtr);
 
    done:
    if (simpleWord) {
        envPtr->wordIsSimple = 1;
        envPtr->numSimpleWordChars = (src - string - 1);
    } else {
        envPtr->wordIsSimple = 0;
        envPtr->numSimpleWordChars = 0;
    }
    envPtr->termOffset = (src - string);
    envPtr->maxStackDepth = 1;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileDollarVar --
 *
 *      Given a string starting with a $ sign, parse a variable name
 *      and compile instructions to push its value. If the variable
 *      reference is just a '$' (i.e. the '$' isn't followed by anything
 *      that could possibly be a variable name), just push a string object
 *      containing '$'.
 *
 * Results:
 *      The return value is a standard Tcl result. If an error occurs
 *      then an error message is left in the interpreter's result.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one in the variable reference.
 *
 *      envPtr->wordIsSimple is set 0 (false) because the word is not
 *      simple: it is not just a sequence of characters without backslashes.
 *      For the same reason, envPtr->numSimpleWordChars is set 0.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the string's commands.
 *
 * Side effects:
 *      Instructions are added to envPtr to look up the variable and
 *      push its value at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileDollarVar(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;          /* Interpreter to use for nested command
                                  * evaluations and error messages. */
    char *string;                /* First char (i.e. $) of var reference. */
    char *lastChar;              /* Pointer to terminating character of
                                  * string. */
    int flags;                   /* Flags to control compilation (same
                                  * values passed to Tcl_Eval). */
    CompileEnv *envPtr;          /* Holds the resulting instructions. */
{
    register char *src = string; /* Points to current source char. */
    register char c;             /* The current char. */
    char *name;                  /* Start of 1st part of variable name. */
    int nameChars;               /* Count of chars in name. */
    int nameHasNsSeparators = 0; /* Set 1 if name contains "::"s. */
    char savedChar;              /* Holds the character from string
                                  * termporarily replaced by a null
                                  * char during name processing. */
    int objIndex;                /* The object array index for a pushed
                                  * object holding a name part. */
    int isArrayRef = 0;           /* 1 if reference to array element. */
    int localIndex = -1;         /* Frame index of local if found.  */
    int maxDepth = 0;             /* Maximum number of stack elements needed
                                  * to push the variable. */
    int savePushSimpleWords = envPtr->pushSimpleWords;
    int result = TCL_OK;
 
    /*
     * var_reference: '$' '{' braced_name '}' |
     *                '$' name ['(' index_string ')']
     *
     * There are three cases:
     * 1. The $ sign is followed by an open curly brace. Then the variable
     *    name is everything up to the next close curly brace, and the
     *    variable is a scalar variable.
     * 2. The $ sign is not followed by an open curly brace. Then the
     *    variable name is everything up to the next character that isn't
     *    a letter, digit, underscore, or a "::" namespace separator. If the
     *    following character is an open parenthesis, then the information
     *    between parentheses is the array element name, which can include
     *    any of the substitutions permissible between quotes.
     * 3. The $ sign is followed by something that isn't a letter, digit,
     *    underscore, or a "::" namespace separator: in this case,
     *    there is no variable name, and "$" is pushed.
     */
 
    src++;                      /* advance over the '$'. */
 
    /*
     * Collect the first part of the variable's name into "name" and
     * determine if it is an array reference and if it contains any
     * namespace separator (::'s).
     */
 
    if (*src == '{') {
        /*
         * A scalar name in braces.
         */
 
        char *p;
 
        src++;
        name = src;
        c = *src;
        while (c != '}') {
            if (src == lastChar) {
                Tcl_ResetResult(interp);
                Tcl_AppendToObj(Tcl_GetObjResult(interp),
                        "missing close-brace for variable name", -1);
                result = TCL_ERROR;
                goto done;
            }
            src++;
            c = *src;
        }
        nameChars = (src - name);
        for (p = name;  p < src;  p++) {
            if ((*p == ':') && (*(p+1) == ':')) {
                nameHasNsSeparators = 1;
                break;
            }
        }
        src++;                  /* advance over the '}'. */
    } else {
        /*
         * Scalar name or array reference not in braces.
         */
 
        name = src;
        c = *src;
        while (isalnum(UCHAR(c)) || (c == '_') || (c == ':')) {
            if (c == ':') {
                if (*(src+1) == ':') {
                    nameHasNsSeparators = 1;
                    src += 2;
                    while (*src == ':') {
                        src++;
                    }
                    c = *src;
                } else {
                    break;      /* : by itself */
                }
            } else {
                src++;
                c = *src;
            }
        }
        if (src == name) {
            /*
             * A '$' by itself, not a name reference. Push a "$" string.
             */
 
            objIndex = TclObjIndexForString("$", 1, /*allocStrRep*/ 1,
                                            /*inHeap*/ 0, envPtr);
            TclEmitPush(objIndex, envPtr);
            maxDepth = 1;
            goto done;
        }
        nameChars = (src - name);
        isArrayRef = (c == '(');
    }
 
    /*
     * Now emit instructions to load the variable. First either push the
     * name of the scalar or array, or determine its index in the array of
     * local variables in a procedure frame. Push the name if we are not
     * compiling a procedure body or if the name has namespace
     * qualifiers ("::"s).
     */
 
    if (!isArrayRef) {          /* scalar reference */
        if ((envPtr->procPtr == NULL) || nameHasNsSeparators) {
            savedChar = name[nameChars];
            name[nameChars] = '\0';
            objIndex = TclObjIndexForString(name, nameChars,
                    /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
            name[nameChars] = savedChar;
            TclEmitPush(objIndex, envPtr);
            TclEmitOpcode(INST_LOAD_SCALAR_STK, envPtr);
            maxDepth = 1;
        } else {
            localIndex = LookupCompiledLocal(name, nameChars,
                    /*createIfNew*/ 0, /*flagsIfCreated*/ 0,
                    envPtr->procPtr);
            if (localIndex >= 0) {
                if (localIndex <= 255) {
                    TclEmitInstUInt1(INST_LOAD_SCALAR1, localIndex, envPtr);
                } else {
                    TclEmitInstUInt4(INST_LOAD_SCALAR4, localIndex, envPtr);
                }
                maxDepth = 0;
            } else {
                savedChar = name[nameChars];
                name[nameChars] = '\0';
                objIndex = TclObjIndexForString(name, nameChars,
                        /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
                name[nameChars] = savedChar;
                TclEmitPush(objIndex, envPtr);
                TclEmitOpcode(INST_LOAD_SCALAR_STK, envPtr);
                maxDepth = 1;
            }
        }
    } else {                    /* array reference */
        if ((envPtr->procPtr == NULL) || nameHasNsSeparators) {
            savedChar = name[nameChars];
            name[nameChars] = '\0';
            objIndex = TclObjIndexForString(name, nameChars,
                    /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
            name[nameChars] = savedChar;
            TclEmitPush(objIndex, envPtr);
            maxDepth = 1;
        } else {
            localIndex = LookupCompiledLocal(name, nameChars,
                    /*createIfNew*/ 0, /*flagsIfCreated*/ 0,
                    envPtr->procPtr);
            if (localIndex < 0) {
                savedChar = name[nameChars];
                name[nameChars] = '\0';
                objIndex = TclObjIndexForString(name, nameChars,
                        /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
                name[nameChars] = savedChar;
                TclEmitPush(objIndex, envPtr);
                maxDepth = 1;
            }
        }
 
        /*
         * Parse and push the array element. Perform substitutions on it,
         * just as is done for quoted strings.
         */
 
        src++;
        envPtr->pushSimpleWords = 1;
        result = TclCompileQuotes(interp, src, lastChar, ')', flags,
                envPtr);
        src += envPtr->termOffset;
        if (result != TCL_OK) {
            char msg[200];
            sprintf(msg, "\n    (parsing index for array \"%.*s\")",
                    (nameChars > 100? 100 : nameChars), name);
            Tcl_AddObjErrorInfo(interp, msg, -1);
            goto done;
        }
        maxDepth += envPtr->maxStackDepth;
 
        /*
         * Now emit the appropriate load instruction for the array element.
         */
 
        if (localIndex < 0) {    /* a global or an unknown local */
            TclEmitOpcode(INST_LOAD_ARRAY_STK, envPtr);
        } else {
            if (localIndex <= 255) {
                TclEmitInstUInt1(INST_LOAD_ARRAY1, localIndex, envPtr);
            } else {
                TclEmitInstUInt4(INST_LOAD_ARRAY4, localIndex, envPtr);
            }
        }
    }
 
    done:
    envPtr->termOffset = (src - string);
    envPtr->wordIsSimple = 0;
    envPtr->numSimpleWordChars = 0;
    envPtr->maxStackDepth = maxDepth;
    envPtr->pushSimpleWords = savePushSimpleWords;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * IsLocalScalar --
 *
 *      Checks to see if a variable name refers to a local scalar.
 *
 * Results:
 *      Returns 1 if the variable is a local scalar.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
 
static int
IsLocalScalar(varName, length)
    char *varName;              /* The name to check. */
    int length;         /* The number of characters in the string.  */
{
    char *p;
    char *lastChar = varName + (length - 1);
 
    for (p = varName; p <= lastChar; p++) {
        if ((CHAR_TYPE(p, lastChar) != TCL_NORMAL) &&
            (CHAR_TYPE(p, lastChar) != TCL_COMMAND_END)) {
            /*
             * TCL_COMMAND_END is returned for the last character
             * of the string.  By this point we know it isn't
             * an array or namespace reference.
             */
 
            return 0;
        }
        if  (*p == '(') {
            if (*lastChar == ')') { /* we have an array element */
                return 0;
            }
        } else if (*p == ':') {
            if ((p != lastChar) && *(p+1) == ':') { /* qualified name */
                return 0;
            }
        }
    }
 
    return 1;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileBreakCmd --
 *
 *      Procedure called to compile the "break" command.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK unless
 *      there was an error while parsing string. If an error occurs then
 *      the interpreter's result contains a standard error message.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the command.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the "break" command
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileBreakCmd(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    register char *src = string;/* Points to current source char. */
    register int type;          /* Current char's CHAR_TYPE type. */
    int result = TCL_OK;
 
    /*
     * There should be no argument after the "break".
     */
 
    type = CHAR_TYPE(src, lastChar);
    if (type != TCL_COMMAND_END) {
        AdvanceToNextWord(src, envPtr);
        src += envPtr->termOffset;
        type = CHAR_TYPE(src, lastChar);
        if (type != TCL_COMMAND_END) {
            Tcl_ResetResult(interp);
            Tcl_AppendToObj(Tcl_GetObjResult(interp),
                    "wrong # args: should be \"break\"", -1);
            result = TCL_ERROR;
            goto done;
        }
    }
 
    /*
     * Emit a break instruction.
     */
 
    TclEmitOpcode(INST_BREAK, envPtr);
 
    done:
    envPtr->termOffset = (src - string);
    envPtr->maxStackDepth = 0;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileCatchCmd --
 *
 *      Procedure called to compile the "catch" command.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK if
 *      compilation was successful. If an error occurs then the
 *      interpreter's result contains a standard error message and TCL_ERROR
 *      is returned. If compilation failed because the command is too
 *      complex for TclCompileCatchCmd, TCL_OUT_LINE_COMPILE is returned
 *      indicating that the catch command should be compiled "out of line"
 *      by emitting code to invoke its command procedure at runtime.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the command.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the "catch" command
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileCatchCmd(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    Proc *procPtr = envPtr->procPtr;
                                /* Points to structure describing procedure
                                 * containing the catch cmd, else NULL. */
    int maxDepth = 0;           /* Maximum number of stack elements needed
                                 * to execute cmd. */
    ArgInfo argInfo;            /* Structure holding information about the
                                 * start and end of each argument word. */
    int range = -1;             /* If we compile the catch command, the
                                 * index for its catch range record in the
                                 * ExceptionRange array. -1 if we are not
                                 * compiling the command. */
    char *name;                 /* If a var name appears for a scalar local
                                 * to a procedure, this points to the name's
                                 * 1st char and nameChars is its length. */
    int nameChars;              /* Length of the variable name, if any. */
    int localIndex = -1;        /* Index of the variable in the current
                                 * procedure's array of local variables.
                                 * Otherwise -1 if not in a procedure or
                                 * the variable wasn't found. */
    char savedChar;             /* Holds the character from string
                                 * termporarily replaced by a null character
                                 * during processing of words. */
    JumpFixup jumpFixup;        /* Used to emit the jump after the "no
                                 * errors" epilogue code. */
    int numWords, objIndex, jumpDist, result;
    char *bodyStart, *bodyEnd;
    Tcl_Obj *objPtr;
    int savePushSimpleWords = envPtr->pushSimpleWords;
 
    /*
     * Scan the words of the command and record the start and finish of
     * each argument word.
     */
 
    InitArgInfo(&argInfo);
    result = CollectArgInfo(interp, string, lastChar, flags, &argInfo);
    numWords = argInfo.numArgs;   /* i.e., the # after the command name */
    if (result != TCL_OK) {
        goto done;
    }
    if ((numWords != 1) && (numWords != 2)) {
        Tcl_ResetResult(interp);
        Tcl_AppendToObj(Tcl_GetObjResult(interp),
                "wrong # args: should be \"catch command ?varName?\"", -1);
        result = TCL_ERROR;
        goto done;
    }
 
    /*
     * If a variable was specified and the catch command is at global level
     * (not in a procedure), don't compile it inline: the payoff is
     * too small.
     */
 
    if ((numWords == 2) && (procPtr == NULL)) {
        result = TCL_OUT_LINE_COMPILE;
        goto done;
    }
 
    /*
     * Make sure the variable name, if any, has no substitutions and just
     * refers to a local scaler.
     */
 
    if (numWords == 2) {
        char *firstChar = argInfo.startArray[1];
        char *lastChar  = argInfo.endArray[1];
 
        if (*firstChar == '{') {
            if (*lastChar != '}') {
                Tcl_ResetResult(interp);
                Tcl_AppendToObj(Tcl_GetObjResult(interp),
                        "extra characters after close-brace", -1);
                result = TCL_ERROR;
                goto done;
            }
            firstChar++;
            lastChar--;
        }
 
        nameChars = (lastChar - firstChar + 1);
        if (!IsLocalScalar(firstChar, nameChars)) {
            result = TCL_OUT_LINE_COMPILE;
            goto done;
        }
 
        name = firstChar;
        localIndex = LookupCompiledLocal(name, nameChars,
                    /*createIfNew*/ 1, /*flagsIfCreated*/ VAR_SCALAR,
                    procPtr);
    }
 
    /*
     *==== At this point we believe we can compile the catch command ====
     */
 
    /*
     * Create and initialize a ExceptionRange record to hold information
     * about this catch command.
     */
 
    envPtr->excRangeDepth++;
    envPtr->maxExcRangeDepth =
        TclMax(envPtr->excRangeDepth, envPtr->maxExcRangeDepth);
    range = CreateExceptionRange(CATCH_EXCEPTION_RANGE, envPtr);
 
    /*
     * Emit the instruction to mark the start of the catch command.
     */
 
    TclEmitInstUInt4(INST_BEGIN_CATCH4, range, envPtr);
 
    /*
     * Inline compile the catch's body word: the command it controls. Also
     * register the body's starting PC offset and byte length in the
     * ExceptionRange record.
     */
 
    envPtr->excRangeArrayPtr[range].codeOffset = TclCurrCodeOffset();
 
    bodyStart = argInfo.startArray[0];
    bodyEnd   = argInfo.endArray[0];
    savedChar = *(bodyEnd+1);
    *(bodyEnd+1) = '\0';
    result = CompileCmdWordInline(interp, bodyStart, (bodyEnd+1),
            flags, envPtr);
    *(bodyEnd+1) = savedChar;
 
    if (result != TCL_OK) {
        if (result == TCL_ERROR) {
            char msg[60];
            sprintf(msg, "\n    (\"catch\" body line %d)",
                    interp->errorLine);
            Tcl_AddObjErrorInfo(interp, msg, -1);
        }
        goto done;
    }
    maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
    envPtr->excRangeArrayPtr[range].numCodeBytes =
        TclCurrCodeOffset() - envPtr->excRangeArrayPtr[range].codeOffset;
 
    /*
     * Now emit the "no errors" epilogue code for the catch. First, if a
     * variable was specified, store the body's result into the
     * variable; otherwise, just discard the body's result. Then push
     * a "0" object as the catch command's "no error" TCL_OK result,
     * and jump around the "error case" epilogue code.
     */
 
    if (localIndex != -1) {
        if (localIndex <= 255) {
            TclEmitInstUInt1(INST_STORE_SCALAR1, localIndex, envPtr);
        } else {
            TclEmitInstUInt4(INST_STORE_SCALAR4, localIndex, envPtr);
        }
    }
    TclEmitOpcode(INST_POP, envPtr);
 
    objIndex = TclObjIndexForString("0", 1, /*allocStrRep*/ 0, /*inHeap*/ 0,
            envPtr);
    objPtr = envPtr->objArrayPtr[objIndex];
 
    Tcl_InvalidateStringRep(objPtr);
    objPtr->internalRep.longValue = 0;
    objPtr->typePtr = &tclIntType;
 
    TclEmitPush(objIndex, envPtr);
    if (maxDepth == 0) {
        maxDepth = 1;   /* since we just pushed one object */
    }
 
    TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &jumpFixup);
 
    /*
     * Now emit the "error case" epilogue code. First, if a variable was
     * specified, emit instructions to push the interpreter's object result
     * and store it into the variable. Then emit an instruction to push the
     * nonzero error result. Note that the initial PC offset here is the
     * catch's error target.
     */
 
    envPtr->excRangeArrayPtr[range].catchOffset = TclCurrCodeOffset();
    if (localIndex != -1) {
        TclEmitOpcode(INST_PUSH_RESULT, envPtr);
        if (localIndex <= 255) {
            TclEmitInstUInt1(INST_STORE_SCALAR1, localIndex, envPtr);
        } else {
            TclEmitInstUInt4(INST_STORE_SCALAR4, localIndex, envPtr);
        }
        TclEmitOpcode(INST_POP, envPtr);
    }
    TclEmitOpcode(INST_PUSH_RETURN_CODE, envPtr);
 
    /*
     * Now that we know the target of the jump after the "no errors"
     * epilogue, update it with the correct distance. This is less
     * than 127 bytes.
     */
 
    jumpDist = (TclCurrCodeOffset() - jumpFixup.codeOffset);
    if (TclFixupForwardJump(envPtr, &jumpFixup, jumpDist, 127)) {
        panic("TclCompileCatchCmd: bad jump distance %d\n", jumpDist);
    }
 
    /*
     * Emit the instruction to mark the end of the catch command.
     */
 
    TclEmitOpcode(INST_END_CATCH, envPtr);
 
    done:
    if (numWords == 0) {
        envPtr->termOffset = 0;
    } else {
        envPtr->termOffset = (argInfo.endArray[numWords-1] + 1 - string);
    }
    if (range != -1) {          /* we compiled the catch command */
        envPtr->excRangeDepth--;
    }
    envPtr->pushSimpleWords = savePushSimpleWords;
    envPtr->maxStackDepth = maxDepth;
    FreeArgInfo(&argInfo);
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileContinueCmd --
 *
 *      Procedure called to compile the "continue" command.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK unless
 *      there was an error while parsing string. If an error occurs then
 *      the interpreter's result contains a standard error message.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the command.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the "continue" command
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileContinueCmd(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    register char *src = string;/* Points to current source char. */
    register int type;          /* Current char's CHAR_TYPE type. */
    int result = TCL_OK;
 
    /*
     * There should be no argument after the "continue".
     */
 
    type = CHAR_TYPE(src, lastChar);
    if (type != TCL_COMMAND_END) {
        AdvanceToNextWord(src, envPtr);
        src += envPtr->termOffset;
        type = CHAR_TYPE(src, lastChar);
        if (type != TCL_COMMAND_END) {
            Tcl_ResetResult(interp);
            Tcl_AppendToObj(Tcl_GetObjResult(interp),
                    "wrong # args: should be \"continue\"", -1);
            result = TCL_ERROR;
            goto done;
        }
    }
 
    /*
     * Emit a continue instruction.
     */
 
    TclEmitOpcode(INST_CONTINUE, envPtr);
 
    done:
    envPtr->termOffset = (src - string);
    envPtr->maxStackDepth = 0;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileExprCmd --
 *
 *      Procedure called to compile the "expr" command.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK
 *      unless there was an error while parsing string. If an error occurs
 *      then the interpreter's result contains a standard error message.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the "expr" command.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the "expr" command
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileExprCmd(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to execute cmd. */
    ArgInfo argInfo;            /* Structure holding information about the
                                 * start and end of each argument word. */
    Tcl_DString buffer;         /* Holds the concatenated expr command
                                 * argument words. */
    int firstWord;              /* 1 if processing the first word; 0 if
                                 * processing subsequent words. */
    char *first, *last;         /* Points to the first and last significant
                                 * chars of the concatenated expression. */
    int inlineCode;             /* 1 if inline "optimistic" code is
                                 * emitted for the expression; else 0. */
    int range = -1;             /* If we inline compile the concatenated
                                 * expression, the index for its catch range
                                 * record in the ExceptionRange array.
                                 * Initialized to avoid compile warning. */
    JumpFixup jumpFixup;        /* Used to emit the "success" jump after
                                 * the inline concat. expression's code. */
    char savedChar;             /* Holds the character termporarily replaced
                                 * by a null character during compilation
                                 * of the concatenated expression. */
    int numWords, objIndex, i, result;
    char *wordStart, *wordEnd, *p;
    char c;
    int savePushSimpleWords = envPtr->pushSimpleWords;
    int saveExprIsJustVarRef = envPtr->exprIsJustVarRef;
    int saveExprIsComparison = envPtr->exprIsComparison;
 
    /*
     * Scan the words of the command and record the start and finish of
     * each argument word.
     */
 
    InitArgInfo(&argInfo);
    result = CollectArgInfo(interp, string, lastChar, flags, &argInfo);
    numWords = argInfo.numArgs;   /* i.e., the # after the command name */
    if (result != TCL_OK) {
        goto done;
    }
    if (numWords == 0) {
        Tcl_ResetResult(interp);
        Tcl_AppendToObj(Tcl_GetObjResult(interp),
                "wrong # args: should be \"expr arg ?arg ...?\"", -1);
        result = TCL_ERROR;
        goto done;
    }
 
    /*
     * If there is a single argument word and it is enclosed in {}s, we may
     * strip them off and safely compile the expr command into an inline
     * sequence of instructions using TclCompileExpr. We know these
     * instructions will have the right Tcl7.x expression semantics.
     *
     * Otherwise, if the word is not enclosed in {}s, or there are multiple
     * words, we may need to call the expr command (Tcl_ExprObjCmd) at
     * runtime. This recompiles the expression each time (typically) and so
     * is slow. However, there are some circumstances where we can still
     * compile inline instructions "optimistically" and check, during their
     * execution, for double substitutions (these appear as nonnumeric
     * operands). We check for any backslash or command substitutions. If
     * none appear, and only variable substitutions are found, we generate
     * inline instructions. If there is a compilation error, we must emit
     * instructions that return the error at runtime, since this is when
     * scripts in Tcl7.x would "see" the error.
     *
     * For now, if there are multiple words, or the single argument word is
     * not in {}s, we concatenate the argument words and strip off any
     * enclosing {}s or ""s. We call the expr command at runtime if
     * either command or backslash substitutions appear (but not if
     * only variable substitutions appear).
     */
 
    if (numWords == 1) {
        wordStart = argInfo.startArray[0]; /* start of 1st arg word */
        wordEnd   = argInfo.endArray[0];   /* last char of 1st arg word */
        if ((*wordStart == '{') && (*wordEnd == '}')) {
            /*
             * Simple case: a single argument word in {}'s.
             */
 
            *wordEnd = '\0';
            result = TclCompileExpr(interp, (wordStart + 1), wordEnd,
                    flags, envPtr);
            *wordEnd = '}';
 
            envPtr->termOffset = (wordEnd + 1) - string;
            envPtr->pushSimpleWords = savePushSimpleWords;
            FreeArgInfo(&argInfo);
            return result;
        }
    }
 
    /*
     * There are multiple words or no braces around the single word.
     * Concatenate the expression's argument words while stripping off
     * any enclosing {}s or ""s.
     */
 
    Tcl_DStringInit(&buffer);
    firstWord = 1;
    for (i = 0;  i < numWords;  i++) {
        wordStart = argInfo.startArray[i];
        wordEnd   = argInfo.endArray[i];
        if (((*wordStart == '{') && (*wordEnd == '}'))
                || ((*wordStart == '"') && (*wordEnd == '"'))) {
            wordStart++;
            wordEnd--;
        }
        if (!firstWord) {
            Tcl_DStringAppend(&buffer, " ", 1);
        }
        firstWord = 0;
        if (wordEnd >= wordStart) {
            Tcl_DStringAppend(&buffer, wordStart, (wordEnd-wordStart+1));
        }
    }
 
    /*
     * Scan the concatenated expression's characters looking for any
     * '['s or (for now) '\'s. If any are found, just call the expr cmd
     * at runtime.
     */
 
    inlineCode = 1;
    first = Tcl_DStringValue(&buffer);
    last = first + (Tcl_DStringLength(&buffer) - 1);
    for (p = first;  p <= last;  p++) {
        c = *p;
        if ((c == '[') || (c == '\\')) {
            inlineCode = 0;
            break;
        }
    }
 
    if (inlineCode) {
        /*
         * Inline compile the concatenated expression inside a "catch"
         * so that a runtime error will back off to a (slow) call on expr.
         */
 
        int startCodeOffset = (envPtr->codeNext - envPtr->codeStart);
        int startRangeNext = envPtr->excRangeArrayNext;
 
        /*
         * Create a ExceptionRange record to hold information about the
         * "catch" range for the expression's inline code. Also emit the
         * instruction to mark the start of the range.
         */
 
        envPtr->excRangeDepth++;
        envPtr->maxExcRangeDepth =
                TclMax(envPtr->excRangeDepth, envPtr->maxExcRangeDepth);
        range = CreateExceptionRange(CATCH_EXCEPTION_RANGE, envPtr);
        TclEmitInstUInt4(INST_BEGIN_CATCH4, range, envPtr);
 
        /*
         * Inline compile the concatenated expression.
         */
 
        envPtr->excRangeArrayPtr[range].codeOffset = TclCurrCodeOffset();
        savedChar = *(last + 1);
        *(last + 1) = '\0';
        result = TclCompileExpr(interp, first, last + 1, flags, envPtr);
        *(last + 1) = savedChar;
 
        maxDepth = envPtr->maxStackDepth;
        envPtr->excRangeArrayPtr[range].numCodeBytes =
                TclCurrCodeOffset() - envPtr->excRangeArrayPtr[range].codeOffset;
 
        if ((result != TCL_OK) || (envPtr->exprIsJustVarRef)
                || (envPtr->exprIsComparison)) {
            /*
             * We must call the expr command at runtime. Either there was a
             * compilation error or the inline code might fail to give the
             * correct 2 level substitution semantics.
             *
             * The latter can happen if the expression consisted of just a
             * single variable reference or if the top-level operator in the
             * expr is a comparison (which might operate on strings). In the
             * latter case, the expression's code might execute (apparently)
             * successfully but produce the wrong result. We depend on its
             * execution failing if a second level of substitutions is
             * required. This causes the "catch" code we generate around the
             * inline code to back off to a call on the expr command at
             * runtime, and this always gives the right 2 level substitution
             * semantics.
             *
             * We delete the inline code by backing up the code pc and catch
             * index. Note that if there was a compilation error, we can't
             * report the error yet since the expression might be valid
             * after the second round of substitutions.
             */
 
            envPtr->codeNext = (envPtr->codeStart + startCodeOffset);
            envPtr->excRangeArrayNext = startRangeNext;
            inlineCode = 0;
        } else {
            TclEmitOpcode(INST_END_CATCH, envPtr); /* for ok case */
            TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &jumpFixup);
            envPtr->excRangeArrayPtr[range].catchOffset = TclCurrCodeOffset();
            TclEmitOpcode(INST_END_CATCH, envPtr); /* for error case */
        }
    }
 
    /*
     * Emit code for the (slow) call on the expr command at runtime.
     * Generate code to concatenate the (already substituted once)
     * expression words with a space between each word.
     */
 
    for (i = 0;  i < numWords;  i++) {
        wordStart = argInfo.startArray[i];
        wordEnd   = argInfo.endArray[i];
        savedChar = *(wordEnd + 1);
        *(wordEnd + 1) = '\0';
        envPtr->pushSimpleWords = 1;
        result = CompileWord(interp, wordStart, wordEnd+1, flags, envPtr);
        *(wordEnd + 1) = savedChar;
        if (result != TCL_OK) {
            break;
        }
        if (i != (numWords - 1)) {
            objIndex = TclObjIndexForString(" ", 1, /*allocStrRep*/ 1,
                                            /*inHeap*/ 0, envPtr);
            TclEmitPush(objIndex, envPtr);
            maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
        } else {
            maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
        }
    }
    if (result == TCL_OK) {
        int concatItems = 2*numWords - 1;
        while (concatItems > 255) {
            TclEmitInstUInt1(INST_CONCAT1, 255, envPtr);
            concatItems -= 254;  /* concat pushes 1 obj, the result */
        }
        if (concatItems > 1) {
            TclEmitInstUInt1(INST_CONCAT1, concatItems, envPtr);
        }
        TclEmitOpcode(INST_EXPR_STK, envPtr);
    }
 
    /*
     * If emitting inline code, update the target of the jump after
     * that inline code.
     */
 
    if (inlineCode) {
        int jumpDist = (TclCurrCodeOffset() - jumpFixup.codeOffset);
        if (TclFixupForwardJump(envPtr, &jumpFixup, jumpDist, 127)) {
            /*
             * Update the inline expression code's catch ExceptionRange
             * target since it, being after the jump, also moved down.
             */
 
            envPtr->excRangeArrayPtr[range].catchOffset += 3;
        }
    }
    Tcl_DStringFree(&buffer);
 
    done:
    if (numWords == 0) {
        envPtr->termOffset = 0;
    } else {
        envPtr->termOffset = (argInfo.endArray[numWords-1] + 1 - string);
    }
    if (range != -1) {          /* we inline compiled the expr */
        envPtr->excRangeDepth--;
    }
    envPtr->pushSimpleWords = savePushSimpleWords;
    envPtr->exprIsJustVarRef = saveExprIsJustVarRef;
    envPtr->exprIsComparison = saveExprIsComparison;
    envPtr->maxStackDepth = maxDepth;
    FreeArgInfo(&argInfo);
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileForCmd --
 *
 *      Procedure called to compile the "for" command.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK unless
 *      there was an error while parsing string. If an error occurs then
 *      the interpreter's result contains a standard error message.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the command.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the "for" command
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileForCmd(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to execute cmd. */
    ArgInfo argInfo;            /* Structure holding information about the
                                 * start and end of each argument word. */
    int range1 = -1, range2;    /* Indexes in the ExceptionRange array of
                                 * the loop ranges for this loop: one for
                                 * its body and one for its "next" cmd. */
    JumpFixup jumpFalseFixup;   /* Used to update or replace the ifFalse
                                 * jump after the "for" test when its target
                                 * PC is determined. */
    int jumpBackDist, jumpBackOffset, testCodeOffset, jumpDist, objIndex;
    unsigned char *jumpPc;
    int savePushSimpleWords = envPtr->pushSimpleWords;
    int numWords, result;
 
    /*
     * Scan the words of the command and record the start and finish of
     * each argument word.
     */
 
    InitArgInfo(&argInfo);
    result = CollectArgInfo(interp, string, lastChar, flags, &argInfo);
    numWords = argInfo.numArgs;   /* i.e., the # after the command name */
    if (result != TCL_OK) {
        goto done;
    }
    if (numWords != 4) {
        Tcl_ResetResult(interp);
        Tcl_AppendToObj(Tcl_GetObjResult(interp),
                "wrong # args: should be \"for start test next command\"", -1);
        result = TCL_ERROR;
        goto done;
    }
 
    /*
     * If the test expression is not enclosed in braces, don't compile
     * the for inline. As a result of Tcl's two level substitution
     * semantics for expressions, the expression might have a constant
     * value that results in the loop never executing, or executing forever.
     * Consider "set x 0; for {} "$x > 5" {incr x} {}": the loop body
     * should never be executed.
     * NOTE: This is an overly aggressive test, since there are legitimate
     * literals that could be compiled but aren't in braces.  However, until
     * the parser is integrated in 8.1, this is the simplest implementation.
     */
 
    if (*(argInfo.startArray[1]) != '{') {
        result = TCL_OUT_LINE_COMPILE;
        goto done;
    }
 
    /*
     * Create a ExceptionRange record for the for loop's body. This is used
     * to implement break and continue commands inside the body.
     * Then create a second ExceptionRange record for the "next" command in
     * order to implement break (but not continue) inside it. The second,
     * "next" ExceptionRange will always have a -1 continueOffset.
     */
 
    envPtr->excRangeDepth++;
    envPtr->maxExcRangeDepth =
        TclMax(envPtr->excRangeDepth, envPtr->maxExcRangeDepth);
    range1 = CreateExceptionRange(LOOP_EXCEPTION_RANGE, envPtr);
    range2 = CreateExceptionRange(LOOP_EXCEPTION_RANGE, envPtr);
 
    /*
     * Compile inline the next word: the initial command.
     */
 
    result = CompileCmdWordInline(interp, argInfo.startArray[0],
            (argInfo.endArray[0] + 1), flags, envPtr);
    if (result != TCL_OK) {
        if (result == TCL_ERROR) {
            Tcl_AddObjErrorInfo(interp, "\n    (\"for\" initial command)", -1);
        }
        goto done;
    }
    maxDepth = envPtr->maxStackDepth;
 
    /*
     * Discard the start command's result.
     */
 
    TclEmitOpcode(INST_POP, envPtr);
 
    /*
     * Compile the next word: the test expression.
     */
 
    testCodeOffset = TclCurrCodeOffset();
    envPtr->pushSimpleWords = 1;    /* process words normally */
    result = CompileExprWord(interp, argInfo.startArray[1],
            (argInfo.endArray[1] + 1), flags, envPtr);
    if (result != TCL_OK) {
        if (result == TCL_ERROR) {
            Tcl_AddObjErrorInfo(interp, "\n    (\"for\" test expression)", -1);
        }
        goto done;
    }
    maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
 
    /*
     * Emit the jump that terminates the for command if the test was
     * false. We emit a one byte (relative) jump here, and replace it later
     * with a four byte jump if the jump target is > 127 bytes away.
     */
 
    TclEmitForwardJump(envPtr, TCL_FALSE_JUMP, &jumpFalseFixup);
 
    /*
     * Compile the loop body word inline. Also register the loop body's
     * starting PC offset and byte length in the its ExceptionRange record.
     */
 
    envPtr->excRangeArrayPtr[range1].codeOffset = TclCurrCodeOffset();
    result = CompileCmdWordInline(interp, argInfo.startArray[3],
            (argInfo.endArray[3] + 1), flags, envPtr);
    if (result != TCL_OK) {
        if (result == TCL_ERROR) {
            char msg[60];
            sprintf(msg, "\n    (\"for\" body line %d)", interp->errorLine);
            Tcl_AddObjErrorInfo(interp, msg, -1);
        }
        goto done;
    }
    maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
    envPtr->excRangeArrayPtr[range1].numCodeBytes =
        (TclCurrCodeOffset() - envPtr->excRangeArrayPtr[range1].codeOffset);
 
    /*
     * Discard the loop body's result.
     */
 
    TclEmitOpcode(INST_POP, envPtr);
 
    /*
     * Finally, compile the "next" subcommand word inline.
     */
 
    envPtr->excRangeArrayPtr[range1].continueOffset = TclCurrCodeOffset();
    envPtr->excRangeArrayPtr[range2].codeOffset = TclCurrCodeOffset();
    result = CompileCmdWordInline(interp, argInfo.startArray[2],
            (argInfo.endArray[2] + 1), flags, envPtr);
    if (result != TCL_OK) {
        if (result == TCL_ERROR) {
            Tcl_AddObjErrorInfo(interp, "\n    (\"for\" loop-end command)", -1);
        }
        goto done;
    }
    maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
    envPtr->excRangeArrayPtr[range2].numCodeBytes =
        TclCurrCodeOffset() - envPtr->excRangeArrayPtr[range2].codeOffset;
 
    /*
     * Discard the "next" subcommand's result.
     */
 
    TclEmitOpcode(INST_POP, envPtr);
 
    /*
     * Emit the unconditional jump back to the test at the top of the for
     * loop. We generate a four byte jump if the distance to the test is
     * greater than 120 bytes. This is conservative, and ensures that we
     * won't have to replace this unconditional jump if we later need to
     * replace the ifFalse jump with a four-byte jump.
     */
 
    jumpBackOffset = TclCurrCodeOffset();
    jumpBackDist = (jumpBackOffset - testCodeOffset);
    if (jumpBackDist > 120) {
        TclEmitInstInt4(INST_JUMP4, /*offset*/ -jumpBackDist, envPtr);
    } else {
        TclEmitInstInt1(INST_JUMP1, /*offset*/ -jumpBackDist, envPtr);
    }
 
    /*
     * Now that we know the target of the jumpFalse after the test, update
     * it with the correct distance. If the distance is too great (more
     * than 127 bytes), replace that jump with a four byte instruction and
     * move the instructions after the jump down.
     */
 
    jumpDist = (TclCurrCodeOffset() - jumpFalseFixup.codeOffset);
    if (TclFixupForwardJump(envPtr, &jumpFalseFixup, jumpDist, 127)) {
        /*
         * Update the loop body's ExceptionRange record since it moved down:
         * i.e., increment both its start and continue PC offsets. Also,
         * update the "next" command's start PC offset in its ExceptionRange
         * record since it also moved down.
         */
 
        envPtr->excRangeArrayPtr[range1].codeOffset += 3;
        envPtr->excRangeArrayPtr[range1].continueOffset += 3;
        envPtr->excRangeArrayPtr[range2].codeOffset += 3;
 
        /*
         * Update the distance for the unconditional jump back to the test
         * at the top of the loop since it moved down 3 bytes too.
         */
 
        jumpBackOffset += 3;
        jumpPc = (envPtr->codeStart + jumpBackOffset);
        if (jumpBackDist > 120) {
            jumpBackDist += 3;
            TclUpdateInstInt4AtPc(INST_JUMP4, /*offset*/ -jumpBackDist,
                                   jumpPc);
        } else {
            jumpBackDist += 3;
            TclUpdateInstInt1AtPc(INST_JUMP1, /*offset*/ -jumpBackDist,
                                   jumpPc);
        }
    }
 
    /*
     * The current PC offset (after the loop's body and "next" subcommand)
     * is the loop's break target.
     */
 
    envPtr->excRangeArrayPtr[range1].breakOffset =
        envPtr->excRangeArrayPtr[range2].breakOffset = TclCurrCodeOffset();
 
    /*
     * Push an empty string object as the for command's result.
     */
 
    objIndex = TclObjIndexForString("", 0, /*allocStrRep*/ 0, /*inHeap*/ 0,
                                    envPtr);
    TclEmitPush(objIndex, envPtr);
    if (maxDepth == 0) {
        maxDepth = 1;
    }
 
    done:
    if (numWords == 0) {
        envPtr->termOffset = 0;
    } else {
        envPtr->termOffset = (argInfo.endArray[numWords-1] + 1 - string);
    }
    envPtr->pushSimpleWords = savePushSimpleWords;
    envPtr->maxStackDepth = maxDepth;
    if (range1 != -1) {
        envPtr->excRangeDepth--;
    }
    FreeArgInfo(&argInfo);
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileForeachCmd --
 *
 *      Procedure called to compile the "foreach" command.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK if
 *      compilation was successful. If an error occurs then the
 *      interpreter's result contains a standard error message and TCL_ERROR
 *      is returned. If complation failed because the command is too complex
 *      for TclCompileForeachCmd, TCL_OUT_LINE_COMPILE is returned
 *      indicating that the foreach command should be compiled "out of line"
 *      by emitting code to invoke its command procedure at runtime.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the "while" command.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the "foreach" command
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileForeachCmd(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    Proc *procPtr = envPtr->procPtr;
                                /* Points to structure describing procedure
                                 * containing foreach command, else NULL. */
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to execute cmd. */
    ArgInfo argInfo;            /* Structure holding information about the
                                 * start and end of each argument word. */
    int numLists = 0;            /* Count of variable (and value) lists. */
    int range = -1;             /* Index in the ExceptionRange array of the
                                 * ExceptionRange record for this loop. */
    ForeachInfo *infoPtr;       /* Points to the structure describing this
                                 * foreach command. Stored in a AuxData
                                 * record in the ByteCode. */
    JumpFixup jumpFalseFixup;   /* Used to update or replace the ifFalse
                                 * jump after test when its target PC is
                                 * determined. */
    char savedChar;             /* Holds the char from string termporarily
                                 * replaced by a null character during
                                 * processing of argument words. */
    int firstListTmp = -1;      /* If we decide to compile this foreach
                                 * command, this is the index or "slot
                                 * number" for the first temp var allocated
                                 * in the proc frame that holds a pointer to
                                 * a value list. Initialized to avoid a
                                 * compiler warning. */
    int loopIterNumTmp;         /* If we decide to compile this foreach
                                 * command, the index for the temp var that
                                 * holds the current iteration count.  */
    char *varListStart, *varListEnd, *valueListStart, *bodyStart, *bodyEnd;
    unsigned char *jumpPc;
    int jumpDist, jumpBackDist, jumpBackOffset;
    int numWords, numVars, infoIndex, tmpIndex, objIndex, i, j, result;
    int savePushSimpleWords = envPtr->pushSimpleWords;
 
    /*
     * We parse the variable list argument words and create two arrays:
     *    varcList[i] gives the number of variables in the i-th var list
     *    varvList[i] points to an array of the names in the i-th var list
     * These are initially allocated on the stack, and are allocated on
     * the heap if necessary.
     */
 
#define STATIC_VAR_LIST_SIZE 4
    int varcListStaticSpace[STATIC_VAR_LIST_SIZE];
    char **varvListStaticSpace[STATIC_VAR_LIST_SIZE];
 
    int *varcList = varcListStaticSpace;
    char ***varvList = varvListStaticSpace;
 
    /*
     * If the foreach command is at global level (not in a procedure),
     * don't compile it inline: the payoff is too small.
     */
 
    if (procPtr == NULL) {
        return TCL_OUT_LINE_COMPILE;
    }
 
    /*
     * Scan the words of the command and record the start and finish of
     * each argument word.
     */
 
    InitArgInfo(&argInfo);
    result = CollectArgInfo(interp, string, lastChar, flags, &argInfo);
    numWords = argInfo.numArgs;
    if (result != TCL_OK) {
        goto done;
    }
    if ((numWords < 3) || (numWords%2 != 1)) {
        Tcl_ResetResult(interp);
        Tcl_AppendToObj(Tcl_GetObjResult(interp),
                "wrong # args: should be \"foreach varList list ?varList list ...? command\"", -1);
        result = TCL_ERROR;
        goto done;
    }
 
    /*
     * Initialize the varcList and varvList arrays; allocate heap storage,
     * if necessary, for them. Also make sure the variable names
     * have no substitutions: that they're just "var" or "var(elem)"
     */
 
    numLists = (numWords - 1)/2;
    if (numLists > STATIC_VAR_LIST_SIZE) {
        varcList = (int *) ckalloc(numLists * sizeof(int));
        varvList = (char ***) ckalloc(numLists * sizeof(char **));
    }
    for (i = 0;  i < numLists;  i++) {
        varcList[i] = 0;
        varvList[i] = (char **) NULL;
    }
    for (i = 0;  i < numLists;  i++) {
        /*
         * Break each variable list into its component variables. If the
         * lists is enclosed in {}s or ""s, strip them off first.
         */
 
        varListStart = argInfo.startArray[i*2];
        varListEnd   = argInfo.endArray[i*2];
        if ((*varListStart == '{') || (*varListStart == '"')) {
            if ((*varListEnd != '}') && (*varListEnd != '"')) {
                Tcl_ResetResult(interp);
                if (*varListStart == '"') {
                    Tcl_AppendToObj(Tcl_GetObjResult(interp),
                            "extra characters after close-quote", -1);
                } else {
                    Tcl_AppendToObj(Tcl_GetObjResult(interp),
                            "extra characters after close-brace", -1);
                }
                result = TCL_ERROR;
                goto done;
            }
            varListStart++;
            varListEnd--;
        }
 
        /*
         * NOTE: THIS NEEDS TO BE CONVERTED TO AN OBJECT LIST.
         */
 
        savedChar = *(varListEnd+1);
        *(varListEnd+1) = '\0';
        result = Tcl_SplitList(interp, varListStart,
                               &varcList[i], &varvList[i]);
        *(varListEnd+1) = savedChar;
        if (result != TCL_OK) {
            goto done;
        }
 
        /*
         * Check that each variable name has no substitutions and that
         * it is a local scalar name.
         */
 
        numVars = varcList[i];
        for (j = 0;  j < numVars;  j++) {
            char *varName = varvList[i][j];
            if (!IsLocalScalar(varName, (int) strlen(varName))) {
                result = TCL_OUT_LINE_COMPILE;
                goto done;
            }
        }
    }
 
    /*
     *==== At this point we believe we can compile the foreach command ====
     */
 
    /*
     * Create and initialize a ExceptionRange record to hold information
     * about this loop. This is used to implement break and continue.
     */
 
    envPtr->excRangeDepth++;
    envPtr->maxExcRangeDepth =
        TclMax(envPtr->excRangeDepth, envPtr->maxExcRangeDepth);
    range = CreateExceptionRange(LOOP_EXCEPTION_RANGE, envPtr);
 
    /*
     * Reserve (numLists + 1) temporary variables:
     *    - numLists temps for each value list
     *    - a temp for the "next value" index into each value list
     * At this time we don't try to reuse temporaries; if there are two
     * nonoverlapping foreach loops, they don't share any temps.
     */
 
    for (i = 0;  i < numLists;  i++) {
        tmpIndex = LookupCompiledLocal(NULL, /*nameChars*/ 0,
                /*createIfNew*/ 1, /*flagsIfCreated*/ VAR_SCALAR, procPtr);
        if (i == 0) {
            firstListTmp = tmpIndex;
        }
    }
    loopIterNumTmp = LookupCompiledLocal(NULL, /*nameChars*/ 0,
            /*createIfNew*/ 1, /*flagsIfCreated*/ VAR_SCALAR, procPtr);
 
    /*
     * Create and initialize the ForeachInfo and ForeachVarList data
     * structures describing this command. Then create a AuxData record
     * pointing to the ForeachInfo structure in the compilation environment.
     */
 
    infoPtr = (ForeachInfo *) ckalloc((unsigned)
            (sizeof(ForeachInfo) + (numLists * sizeof(ForeachVarList *))));
    infoPtr->numLists = numLists;
    infoPtr->firstListTmp = firstListTmp;
    infoPtr->loopIterNumTmp = loopIterNumTmp;
    for (i = 0;  i < numLists;  i++) {
        ForeachVarList *varListPtr;
        numVars = varcList[i];
        varListPtr = (ForeachVarList *) ckalloc((unsigned)
                sizeof(ForeachVarList) + numVars*sizeof(int));
        varListPtr->numVars = numVars;
        for (j = 0;  j < numVars;  j++) {
            char *varName = varvList[i][j];
            int nameChars = strlen(varName);
            varListPtr->varIndexes[j] = LookupCompiledLocal(varName,
                    nameChars, /*createIfNew*/ 1,
                    /*flagsIfCreated*/ VAR_SCALAR, procPtr);
        }
        infoPtr->varLists[i] = varListPtr;
    }
    infoIndex = TclCreateAuxData((ClientData) infoPtr,
            &tclForeachInfoType, envPtr);
 
    /*
     * Emit code to store each value list into the associated temporary.
     */
 
    for (i = 0;  i < numLists;  i++) {
        valueListStart = argInfo.startArray[2*i + 1];
        envPtr->pushSimpleWords = 1;
        result = CompileWord(interp, valueListStart, lastChar, flags,
                envPtr);
        if (result != TCL_OK) {
            goto done;
        }
        maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
 
        tmpIndex = (firstListTmp + i);
        if (tmpIndex <= 255) {
            TclEmitInstUInt1(INST_STORE_SCALAR1, tmpIndex, envPtr);
        } else {
            TclEmitInstUInt4(INST_STORE_SCALAR4, tmpIndex, envPtr);
        }
        TclEmitOpcode(INST_POP, envPtr);
    }
 
    /*
     * Emit the instruction to initialize the foreach loop's index temp var.
     */
 
    TclEmitInstUInt4(INST_FOREACH_START4, infoIndex, envPtr);
 
    /*
     * Emit the top of loop code that assigns each loop variable and checks
     * whether to terminate the loop.
     */
 
    envPtr->excRangeArrayPtr[range].continueOffset = TclCurrCodeOffset();
    TclEmitInstUInt4(INST_FOREACH_STEP4, infoIndex, envPtr);
 
    /*
     * Emit the ifFalse jump that terminates the foreach if all value lists
     * are exhausted. We emit a one byte (relative) jump here, and replace
     * it later with a four byte jump if the jump target is more than
     * 127 bytes away.
     */
 
    TclEmitForwardJump(envPtr, TCL_FALSE_JUMP, &jumpFalseFixup);
 
    /*
     * Compile the loop body word inline. Also register the loop body's
     * starting PC offset and byte length in the ExceptionRange record.
     */
 
    bodyStart = argInfo.startArray[numWords - 1];
    bodyEnd   = argInfo.endArray[numWords - 1];
    savedChar = *(bodyEnd+1);
    *(bodyEnd+1) = '\0';
    envPtr->excRangeArrayPtr[range].codeOffset = TclCurrCodeOffset();
    result = CompileCmdWordInline(interp, bodyStart, bodyEnd+1, flags,
            envPtr);
    *(bodyEnd+1) = savedChar;
    if (result != TCL_OK) {
        if (result == TCL_ERROR) {
            char msg[60];
            sprintf(msg, "\n    (\"foreach\" body line %d)",
                    interp->errorLine);
            Tcl_AddObjErrorInfo(interp, msg, -1);
        }
        goto done;
    }
    maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
    envPtr->excRangeArrayPtr[range].numCodeBytes =
        TclCurrCodeOffset() - envPtr->excRangeArrayPtr[range].codeOffset;
 
    /*
     * Discard the loop body's result.
     */
 
    TclEmitOpcode(INST_POP, envPtr);
 
    /*
     * Emit the unconditional jump back to the test at the top of the
     * loop. We generate a four byte jump if the distance to the to of
     * the foreach is greater than 120 bytes. This is conservative and
     * ensures that we won't have to replace this unconditional jump if
     * we later need to replace the ifFalse jump with a four-byte jump.
     */
 
    jumpBackOffset = TclCurrCodeOffset();
    jumpBackDist =
        (jumpBackOffset - envPtr->excRangeArrayPtr[range].continueOffset);
    if (jumpBackDist > 120) {
        TclEmitInstInt4(INST_JUMP4, /*offset*/ -jumpBackDist, envPtr);
    } else {
        TclEmitInstInt1(INST_JUMP1, /*offset*/ -jumpBackDist, envPtr);
    }
 
    /*
     * Now that we know the target of the jumpFalse after the foreach_step
     * test, update it with the correct distance. If the distance is too
     * great (more than 127 bytes), replace that jump with a four byte
     * instruction and move the instructions after the jump down.
     */
 
    jumpDist = (TclCurrCodeOffset() - jumpFalseFixup.codeOffset);
    if (TclFixupForwardJump(envPtr, &jumpFalseFixup, jumpDist, 127)) {
        /*
         * Update the loop body's starting PC offset since it moved down.
         */
 
        envPtr->excRangeArrayPtr[range].codeOffset += 3;
 
        /*
         * Update the distance for the unconditional jump back to the test
         * at the top of the loop since it moved down 3 bytes too.
         */
 
        jumpBackOffset += 3;
        jumpPc = (envPtr->codeStart + jumpBackOffset);
        if (jumpBackDist > 120) {
            jumpBackDist += 3;
            TclUpdateInstInt4AtPc(INST_JUMP4, /*offset*/ -jumpBackDist,
                                   jumpPc);
        } else {
            jumpBackDist += 3;
            TclUpdateInstInt1AtPc(INST_JUMP1, /*offset*/ -jumpBackDist,
                                   jumpPc);
        }
    }
 
    /*
     * The current PC offset (after the loop's body) is the loop's
     * break target.
     */
 
    envPtr->excRangeArrayPtr[range].breakOffset = TclCurrCodeOffset();
 
    /*
     * Push an empty string object as the foreach command's result.
     */
 
    objIndex = TclObjIndexForString("", 0, /*allocStrRep*/ 0, /*inHeap*/ 0,
                                    envPtr);
    TclEmitPush(objIndex, envPtr);
    if (maxDepth == 0) {
        maxDepth = 1;
    }
 
    done:
    for (i = 0;  i < numLists;  i++) {
        if (varvList[i] != (char **) NULL) {
            ckfree((char *) varvList[i]);
        }
    }
    if (varcList != varcListStaticSpace) {
        ckfree((char *) varcList);
        ckfree((char *) varvList);
    }
    envPtr->termOffset = (argInfo.endArray[numWords-1] + 1 - string);
    envPtr->pushSimpleWords = savePushSimpleWords;
    envPtr->maxStackDepth = maxDepth;
    if (range != -1) {
        envPtr->excRangeDepth--;
    }
    FreeArgInfo(&argInfo);
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * DupForeachInfo --
 *
 *      This procedure duplicates a ForeachInfo structure created as
 *      auxiliary data during the compilation of a foreach command.
 *
 * Results:
 *      A pointer to a newly allocated copy of the existing ForeachInfo
 *      structure is returned.
 *
 * Side effects:
 *      Storage for the copied ForeachInfo record is allocated. If the
 *      original ForeachInfo structure pointed to any ForeachVarList
 *      records, these structures are also copied and pointers to them
 *      are stored in the new ForeachInfo record.
 *
 *----------------------------------------------------------------------
 */
 
static ClientData
DupForeachInfo(clientData)
    ClientData clientData;      /* The foreach command's compilation
                                 * auxiliary data to duplicate. */
{
    register ForeachInfo *srcPtr = (ForeachInfo *) clientData;
    ForeachInfo *dupPtr;
    register ForeachVarList *srcListPtr, *dupListPtr;
    int numLists = srcPtr->numLists;
    int numVars, i, j;
 
    dupPtr = (ForeachInfo *) ckalloc((unsigned)
            (sizeof(ForeachInfo) + (numLists * sizeof(ForeachVarList *))));
    dupPtr->numLists = numLists;
    dupPtr->firstListTmp = srcPtr->firstListTmp;
    dupPtr->loopIterNumTmp = srcPtr->loopIterNumTmp;
 
    for (i = 0;  i < numLists;  i++) {
        srcListPtr = srcPtr->varLists[i];
        numVars = srcListPtr->numVars;
        dupListPtr = (ForeachVarList *) ckalloc((unsigned)
                sizeof(ForeachVarList) + numVars*sizeof(int));
        dupListPtr->numVars = numVars;
        for (j = 0;  j < numVars;  j++) {
            dupListPtr->varIndexes[j] = srcListPtr->varIndexes[j];
        }
        dupPtr->varLists[i] = dupListPtr;
    }
    return (ClientData) dupPtr;
}
 
/*
 *----------------------------------------------------------------------
 *
 * FreeForeachInfo --
 *
 *      Procedure to free a ForeachInfo structure created as auxiliary data
 *      during the compilation of a foreach command.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Storage for the ForeachInfo structure pointed to by the ClientData
 *      argument is freed as is any ForeachVarList record pointed to by the
 *      ForeachInfo structure.
 *
 *----------------------------------------------------------------------
 */
 
static void
FreeForeachInfo(clientData)
    ClientData clientData;      /* The foreach command's compilation
                                 * auxiliary data to free. */
{
    register ForeachInfo *infoPtr = (ForeachInfo *) clientData;
    register ForeachVarList *listPtr;
    int numLists = infoPtr->numLists;
    register int i;
 
    for (i = 0;  i < numLists;  i++) {
        listPtr = infoPtr->varLists[i];
        ckfree((char *) listPtr);
    }
    ckfree((char *) infoPtr);
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileIfCmd --
 *
 *      Procedure called to compile the "if" command.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK unless
 *      there was an error while parsing string. If an error occurs then
 *      the interpreter's result contains a standard error message.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the command.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the "if" command
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileIfCmd(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    register char *src = string;/* Points to current source char. */
    register int type;          /* Current char's CHAR_TYPE type. */
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to execute cmd. */
    JumpFixupArray jumpFalseFixupArray;
                                /* Used to fix up the ifFalse jump after
                                 * each "if"/"elseif" test when its target
                                 * PC is determined. */
    JumpFixupArray jumpEndFixupArray;
                                /* Used to fix up the unconditional jump
                                 * after each "then" command to the end of
                                 * the "if" when that PC is determined. */
    char *testSrcStart;
    int jumpDist, jumpFalseDist, jumpIndex, objIndex, j, result;
    unsigned char *ifFalsePc;
    unsigned char opCode;
    int savePushSimpleWords = envPtr->pushSimpleWords;
 
    /*
     * Loop compiling "expr then body" clauses after an "if" or "elseif".
     */
 
    TclInitJumpFixupArray(&jumpFalseFixupArray);
    TclInitJumpFixupArray(&jumpEndFixupArray);
    while (1) {
        /*
         * At this point in the loop, we have an expression to test, either
         * the main expression or an expression following an "elseif".
         * The arguments after the expression must be "then" (optional) and
         * a script to execute if the expression is true.
         */
 
        AdvanceToNextWord(src, envPtr);
        src += envPtr->termOffset;
        type = CHAR_TYPE(src, lastChar);
        if (type == TCL_COMMAND_END) {
            Tcl_ResetResult(interp);
            Tcl_AppendToObj(Tcl_GetObjResult(interp),
                    "wrong # args: no expression after \"if\" argument", -1);
            result = TCL_ERROR;
            goto done;
        }
 
        /*
         * Compile the "if"/"elseif" test expression.
         */
 
        testSrcStart = src;
        envPtr->pushSimpleWords = 1;
        result = CompileExprWord(interp, src, lastChar, flags, envPtr);
        if (result != TCL_OK) {
            if (result == TCL_ERROR) {
                Tcl_AddObjErrorInfo(interp,
                        "\n    (\"if\" test expression)", -1);
            }
            goto done;
        }
        maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
        src += envPtr->termOffset;
 
        /*
         * Emit the ifFalse jump around the "then" part if the test was
         * false. We emit a one byte (relative) jump here, and replace it
         * later with a four byte jump if the jump target is more than 127
         * bytes away.
         */
 
        if (jumpFalseFixupArray.next >= jumpFalseFixupArray.end) {
            TclExpandJumpFixupArray(&jumpFalseFixupArray);
        }
        jumpIndex = jumpFalseFixupArray.next;
        jumpFalseFixupArray.next++;
        TclEmitForwardJump(envPtr, TCL_FALSE_JUMP,
                &(jumpFalseFixupArray.fixup[jumpIndex]));
 
        /*
         * Skip over the optional "then" before the then clause.
         */
 
        AdvanceToNextWord(src, envPtr);
        src += envPtr->termOffset;
        type = CHAR_TYPE(src, lastChar);
        if (type == TCL_COMMAND_END) {
            char buf[100];
            sprintf(buf, "wrong # args: no script following \"%.20s\" argument", testSrcStart);
            Tcl_ResetResult(interp);
            Tcl_AppendToObj(Tcl_GetObjResult(interp), buf, -1);
            result = TCL_ERROR;
            goto done;
        }
        if ((*src == 't') && (strncmp(src, "then", 4) == 0)) {
            type = CHAR_TYPE(src+4, lastChar);
            if ((type == TCL_SPACE) || (type == TCL_COMMAND_END)) {
                src += 4;
                AdvanceToNextWord(src, envPtr);
                src += envPtr->termOffset;
                type = CHAR_TYPE(src, lastChar);
                if (type == TCL_COMMAND_END) {
                    Tcl_ResetResult(interp);
                    Tcl_AppendToObj(Tcl_GetObjResult(interp),
                            "wrong # args: no script following \"then\" argument", -1);
                    result = TCL_ERROR;
                    goto done;
                }
            }
        }
 
        /*
         * Compile the "then" command word inline.
         */
 
        result = CompileCmdWordInline(interp, src, lastChar, flags, envPtr);
        if (result != TCL_OK) {
            if (result == TCL_ERROR) {
                char msg[60];
                sprintf(msg, "\n    (\"if\" then script line %d)",
                        interp->errorLine);
                Tcl_AddObjErrorInfo(interp, msg, -1);
            }
            goto done;
        }
        maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
        src += envPtr->termOffset;
 
        /*
         * Emit an unconditional jump to the end of the "if" command. We
         * emit a one byte jump here, and replace it later with a four byte
         * jump if the jump target is more than 127 bytes away. Note that
         * both the jumpFalseFixupArray and the jumpEndFixupArray are
         * indexed by the same index, "jumpIndex".
         */
 
        if (jumpEndFixupArray.next >= jumpEndFixupArray.end) {
            TclExpandJumpFixupArray(&jumpEndFixupArray);
        }
        jumpEndFixupArray.next++;
        TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP,
                &(jumpEndFixupArray.fixup[jumpIndex]));
 
        /*
         * Now that we know the target of the jumpFalse after the if test,
         * update it with the correct distance. We generate a four byte
         * jump if the distance is greater than 120 bytes. This is
         * conservative, and ensures that we won't have to replace this
         * jump if we later also need to replace the preceeding
         * unconditional jump to the end of the "if" with a four-byte jump.
         */
 
        jumpDist = (TclCurrCodeOffset() - jumpFalseFixupArray.fixup[jumpIndex].codeOffset);
        if (TclFixupForwardJump(envPtr,
                &(jumpFalseFixupArray.fixup[jumpIndex]), jumpDist, 120)) {
            /*
             * Adjust the code offset for the unconditional jump at the end
             * of the last "then" clause.
             */
 
            jumpEndFixupArray.fixup[jumpIndex].codeOffset += 3;
        }
 
        /*
         * Check now for a "elseif" word. If we find one, keep looping.
         */
 
        AdvanceToNextWord(src, envPtr);
        src += envPtr->termOffset;
        type = CHAR_TYPE(src, lastChar);
        if ((type != TCL_COMMAND_END)
                && ((*src == 'e') && (strncmp(src, "elseif", 6) == 0))) {
            type = CHAR_TYPE(src+6, lastChar);
            if ((type == TCL_SPACE) || (type == TCL_COMMAND_END)) {
                src += 6;
                AdvanceToNextWord(src, envPtr);
                src += envPtr->termOffset;
                type = CHAR_TYPE(src, lastChar);
                if (type == TCL_COMMAND_END) {
                    Tcl_ResetResult(interp);
                    Tcl_AppendToObj(Tcl_GetObjResult(interp),
                            "wrong # args: no expression after \"elseif\" argument", -1);
                    result = TCL_ERROR;
                    goto done;
                }
                continue;         /* continue the "expr then body" loop */
            }
        }
        break;
    } /* end of the "expr then body" loop */
 
    /*
     * No more "elseif expr then body" clauses. Check now for an "else"
     * clause. If there is another word, we are at its start.
     */
 
    if (type != TCL_COMMAND_END) {
        if ((*src == 'e') && (strncmp(src, "else", 4) == 0)) {
            type = CHAR_TYPE(src+4, lastChar);
            if ((type == TCL_SPACE) || (type == TCL_COMMAND_END)) {
                src += 4;
                AdvanceToNextWord(src, envPtr);
                src += envPtr->termOffset;
                type = CHAR_TYPE(src, lastChar);
                if (type == TCL_COMMAND_END) {
                    Tcl_ResetResult(interp);
                    Tcl_AppendToObj(Tcl_GetObjResult(interp),
                            "wrong # args: no script following \"else\" argument", -1);
                    result = TCL_ERROR;
                    goto done;
                }
            }
        }
 
        /*
         * Compile the "else" command word inline.
         */
 
        result = CompileCmdWordInline(interp, src, lastChar, flags, envPtr);
        if (result != TCL_OK) {
            if (result == TCL_ERROR) {
                char msg[60];
                sprintf(msg, "\n    (\"if\" else script line %d)",
                        interp->errorLine);
                Tcl_AddObjErrorInfo(interp, msg, -1);
            }
            goto done;
        }
        maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
        src += envPtr->termOffset;
 
        /*
         * Skip over white space until the end of the command.
         */
 
        type = CHAR_TYPE(src, lastChar);
        if (type != TCL_COMMAND_END) {
            AdvanceToNextWord(src, envPtr);
            src += envPtr->termOffset;
            type = CHAR_TYPE(src, lastChar);
            if (type != TCL_COMMAND_END) {
                Tcl_ResetResult(interp);
                Tcl_AppendToObj(Tcl_GetObjResult(interp),
                        "wrong # args: extra words after \"else\" clause in \"if\" command", -1);
                result = TCL_ERROR;
                goto done;
            }
        }
    } else {
        /*
         * The "if" command has no "else" clause: push an empty string
         * object as its result.
         */
 
        objIndex = TclObjIndexForString("", 0, /*allocStrRep*/ 0,
                /*inHeap*/ 0, envPtr);
        TclEmitPush(objIndex, envPtr);
        maxDepth = TclMax(1, maxDepth);
    }
 
    /*
     * Now that we know the target of the unconditional jumps to the end of
     * the "if" command, update them with the correct distance. If the
     * distance is too great (> 127 bytes), replace the jump with a four
     * byte instruction and move instructions after the jump down.
     */
 
    for (j = jumpEndFixupArray.next;  j > 0;  j--) {
        jumpIndex = (j - 1);    /* i.e. process the closest jump first */
        jumpDist = (TclCurrCodeOffset() - jumpEndFixupArray.fixup[jumpIndex].codeOffset);
        if (TclFixupForwardJump(envPtr,
                &(jumpEndFixupArray.fixup[jumpIndex]), jumpDist, 127)) {
            /*
             * Adjust the jump distance for the "ifFalse" jump that
             * immediately preceeds this jump. We've moved it's target
             * (just after this unconditional jump) three bytes down.
             */
 
            ifFalsePc = (envPtr->codeStart + jumpFalseFixupArray.fixup[jumpIndex].codeOffset);
            opCode = *ifFalsePc;
            if (opCode == INST_JUMP_FALSE1) {
                jumpFalseDist = TclGetInt1AtPtr(ifFalsePc + 1);
                jumpFalseDist += 3;
                TclStoreInt1AtPtr(jumpFalseDist, (ifFalsePc + 1));
            } else if (opCode == INST_JUMP_FALSE4) {
                jumpFalseDist = TclGetInt4AtPtr(ifFalsePc + 1);
                jumpFalseDist += 3;
                TclStoreInt4AtPtr(jumpFalseDist, (ifFalsePc + 1));
            } else {
                panic("TclCompileIfCmd: unexpected opcode updating ifFalse jump");
            }
        }
    }
 
    /*
     * Free the jumpFixupArray array if malloc'ed storage was used.
     */
 
    done:
    TclFreeJumpFixupArray(&jumpFalseFixupArray);
    TclFreeJumpFixupArray(&jumpEndFixupArray);
    envPtr->termOffset = (src - string);
    envPtr->maxStackDepth = maxDepth;
    envPtr->pushSimpleWords = savePushSimpleWords;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileIncrCmd --
 *
 *      Procedure called to compile the "incr" command.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK unless
 *      there was an error while parsing string. If an error occurs then
 *      the interpreter's result contains a standard error message.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the "incr" command.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the "incr" command
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileIncrCmd(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    Proc *procPtr = envPtr->procPtr;
                                /* Points to structure describing procedure
                                 * containing incr command, else NULL. */
    register char *src = string;
                                /* Points to current source char. */
    register int type;          /* Current char's CHAR_TYPE type. */
    int simpleVarName;          /* 1 if name is just sequence of chars with
                                 * an optional element name in parens. */
    char *name = NULL;          /* If simpleVarName, points to first char of
                                 * variable name and nameChars is length.
                                 * Otherwise NULL. */
    char *elName = NULL;        /* If simpleVarName, points to first char of
                                 * element name and elNameChars is length.
                                 * Otherwise NULL. */
    int nameChars = 0;           /* Length of the var name. Initialized to
                                 * avoid a compiler warning. */
    int elNameChars = 0; /* Length of array's element name, if any.
                                 * Initialized to avoid a compiler
                                 * warning. */
    int incrementGiven;         /* 1 if an increment amount was given. */
    int isImmIncrValue = 0;      /* 1 if increment amount is a literal
                                 * integer in [-127..127]. */
    int immIncrValue = 0;        /* if isImmIncrValue is 1, the immediate
                                 * integer value. */
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to execute cmd. */
    int localIndex = -1;        /* Index of the variable in the current
                                 * procedure's array of local variables.
                                 * Otherwise -1 if not in a procedure or
                                 * the variable wasn't found. */
    char savedChar;             /* Holds the character from string
                                 * termporarily replaced by a null char
                                 * during name processing. */
    int objIndex;               /* The object array index for a pushed
                                 * object holding a name part. */
    int savePushSimpleWords = envPtr->pushSimpleWords;
    char *p;
    int i, result;
 
    /*
     * Parse the next word: the variable name. If it is "simple" (requires
     * no substitutions at runtime), divide it up into a simple "name" plus
     * an optional "elName". Otherwise, if not simple, just push the name.
     */
 
    AdvanceToNextWord(src, envPtr);
    src += envPtr->termOffset;
    type = CHAR_TYPE(src, lastChar);
    if (type == TCL_COMMAND_END) {
        badArgs:
        Tcl_ResetResult(interp);
        Tcl_AppendToObj(Tcl_GetObjResult(interp),
                "wrong # args: should be \"incr varName ?increment?\"", -1);
        result = TCL_ERROR;
        goto done;
    }
 
    envPtr->pushSimpleWords = 0;
    result = CompileWord(interp, src, lastChar, flags, envPtr);
    if (result != TCL_OK) {
        goto done;
    }
    simpleVarName = envPtr->wordIsSimple;
    if (simpleVarName) {
        name = src;
        nameChars = envPtr->numSimpleWordChars;
        if (type & (TCL_QUOTE | TCL_OPEN_BRACE)) {
            name++;
        }
        elName = NULL;
        elNameChars = 0;
        p = name;
        for (i = 0;  i < nameChars;  i++) {
            if (*p == '(') {
                char *openParen = p;
                p = (src + nameChars-1);
                if (*p == ')') { /* last char is ')' => array reference */
                    nameChars = (openParen - name);
                    elName = openParen+1;
                    elNameChars = (p - elName);
                }
                break;
            }
            p++;
        }
    } else {
        maxDepth = envPtr->maxStackDepth;
    }
    src += envPtr->termOffset;
 
    /*
     * See if there is a next word. If so, we are incrementing the variable
     * by that value (which must be an integer).
     */
 
    incrementGiven = 0;
    type = CHAR_TYPE(src, lastChar);
    if (type != TCL_COMMAND_END) {
        AdvanceToNextWord(src, envPtr);
        src += envPtr->termOffset;
        type = CHAR_TYPE(src, lastChar);
        incrementGiven = (type != TCL_COMMAND_END);
    }
 
    /*
     * Non-simple names have already been pushed. If this is a simple
     * variable, either push its name (if a global or an unknown local
     * variable) or look up the variable's local frame index. If a local is
     * not found, push its name and do the lookup at runtime. If this is an
     * array reference, also push the array element.
     */
 
    if (simpleVarName) {
        if (procPtr == NULL) {
            savedChar = name[nameChars];
            name[nameChars] = '\0';
            objIndex = TclObjIndexForString(name, nameChars,
                    /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
            name[nameChars] = savedChar;
            TclEmitPush(objIndex, envPtr);
            maxDepth = 1;
        } else {
            localIndex = LookupCompiledLocal(name, nameChars,
                    /*createIfNew*/ 0, /*flagsIfCreated*/ 0,
                    envPtr->procPtr);
            if ((localIndex < 0) || (localIndex > 255)) {
                if (localIndex > 255) {       /* we'll push the name */
                    localIndex = -1;
                }
                savedChar = name[nameChars];
                name[nameChars] = '\0';
                objIndex = TclObjIndexForString(name, nameChars,
                        /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
                name[nameChars] = savedChar;
                TclEmitPush(objIndex, envPtr);
                maxDepth = 1;
            } else {
                maxDepth = 0;
            }
        }
 
        if (elName != NULL) {
            /*
             * Parse and push the array element's name. Perform
             * substitutions on it, just as is done for quoted strings.
             */
 
            savedChar = elName[elNameChars];
            elName[elNameChars] = '\0';
            envPtr->pushSimpleWords = 1;
            result = TclCompileQuotes(interp, elName, elName+elNameChars,
                    0, flags, envPtr);
            elName[elNameChars] = savedChar;
            if (result != TCL_OK) {
                char msg[200];
                sprintf(msg, "\n    (parsing index for array \"%.*s\")",
                        TclMin(nameChars, 100), name);
                Tcl_AddObjErrorInfo(interp, msg, -1);
                goto done;
            }
            maxDepth += envPtr->maxStackDepth;
        }
    }
 
    /*
     * If an increment was given, push the new value.
     */
 
    if (incrementGiven) {
        type = CHAR_TYPE(src, lastChar);
        envPtr->pushSimpleWords = 0;
        result = CompileWord(interp, src, lastChar, flags, envPtr);
        if (result != TCL_OK) {
            if (result == TCL_ERROR) {
                Tcl_AddObjErrorInfo(interp,
                        "\n    (increment expression)", -1);
            }
            goto done;
        }
        if (type & (TCL_QUOTE | TCL_OPEN_BRACE)) {
            src++;
        }
        if (envPtr->wordIsSimple) {
            /*
             * See if the word represents an integer whose formatted
             * representation is the same as the word (e.g., this is
             * true for 123 and -1 but not for 00005). If so, just
             * push an integer object.
             */
 
            int isCompilableInt = 0;
            int numChars = envPtr->numSimpleWordChars;
            char savedChar = src[numChars];
            char buf[40];
            Tcl_Obj *objPtr;
            long n;
 
            src[numChars] = '\0';
            if (TclLooksLikeInt(src)) {
                int code = TclGetLong(interp, src, &n);
                if (code == TCL_OK) {
                    if ((-127 <= n) && (n <= 127)) {
                        isCompilableInt = 1;
                        isImmIncrValue = 1;
                        immIncrValue = n;
                    } else {
                        TclFormatInt(buf, n);
                        if (strcmp(src, buf) == 0) {
                            isCompilableInt = 1;
                            isImmIncrValue = 0;
                            objIndex = TclObjIndexForString(src, numChars,
                                /*allocStrRep*/ 0, /*inHeap*/ 0, envPtr);
                            objPtr = envPtr->objArrayPtr[objIndex];
 
                            Tcl_InvalidateStringRep(objPtr);
                            objPtr->internalRep.longValue = n;
                            objPtr->typePtr = &tclIntType;
 
                            TclEmitPush(objIndex, envPtr);
                            maxDepth += 1;
                        }
                    }
                } else {
                    Tcl_ResetResult(interp);
                }
            }
            if (!isCompilableInt) {
                objIndex = TclObjIndexForString(src, numChars,
                        /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
                TclEmitPush(objIndex, envPtr);
                maxDepth += 1;
            }
            src[numChars] = savedChar;
        } else {
            maxDepth += envPtr->maxStackDepth;
        }
        if (type & (TCL_QUOTE | TCL_OPEN_BRACE)) {
            src += (envPtr->termOffset - 1); /* already advanced 1 above */
        } else {
            src += envPtr->termOffset;
        }
    } else {                    /* no incr amount given so use 1 */
        isImmIncrValue = 1;
        immIncrValue = 1;
    }
 
    /*
     * Now emit instructions to increment the variable.
     */
 
    if (simpleVarName) {
        if (elName == NULL) {  /* scalar */
            if (localIndex >= 0) {
                if (isImmIncrValue) {
                    TclEmitInstUInt1(INST_INCR_SCALAR1_IMM, localIndex,
                                    envPtr);
                    TclEmitInt1(immIncrValue, envPtr);
                } else {
                    TclEmitInstUInt1(INST_INCR_SCALAR1, localIndex, envPtr);
                }
            } else {
                if (isImmIncrValue) {
                    TclEmitInstInt1(INST_INCR_SCALAR_STK_IMM, immIncrValue,
                                   envPtr);
                } else {
                    TclEmitOpcode(INST_INCR_SCALAR_STK, envPtr);
                }
            }
        } else {                /* array */
            if (localIndex >= 0) {
                if (isImmIncrValue) {
                    TclEmitInstUInt1(INST_INCR_ARRAY1_IMM, localIndex,
                                    envPtr);
                    TclEmitInt1(immIncrValue, envPtr);
                } else {
                    TclEmitInstUInt1(INST_INCR_ARRAY1, localIndex, envPtr);
                }
            } else {
                if (isImmIncrValue) {
                    TclEmitInstInt1(INST_INCR_ARRAY_STK_IMM, immIncrValue,
                                   envPtr);
                } else {
                    TclEmitOpcode(INST_INCR_ARRAY_STK, envPtr);
                }
            }
        }
    } else {                    /* non-simple variable name */
        if (isImmIncrValue) {
            TclEmitInstInt1(INST_INCR_STK_IMM, immIncrValue, envPtr);
        } else {
            TclEmitOpcode(INST_INCR_STK, envPtr);
        }
    }
 
    /*
     * Skip over white space until the end of the command.
     */
 
    type = CHAR_TYPE(src, lastChar);
    if (type != TCL_COMMAND_END) {
        AdvanceToNextWord(src, envPtr);
        src += envPtr->termOffset;
        type = CHAR_TYPE(src, lastChar);
        if (type != TCL_COMMAND_END) {
            goto badArgs;
        }
    }
 
    done:
    envPtr->termOffset = (src - string);
    envPtr->maxStackDepth = maxDepth;
    envPtr->pushSimpleWords = savePushSimpleWords;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileSetCmd --
 *
 *      Procedure called to compile the "set" command.
 *
 * Results:
 *      The return value is a standard Tcl result, which is normally TCL_OK
 *      unless there was an error while parsing string. If an error occurs
 *      then the interpreter's result contains a standard error message. If
 *      complation fails because the set command requires a second level of
 *      substitutions, TCL_OUT_LINE_COMPILE is returned indicating that the
 *      set command should be compiled "out of line" by emitting code to
 *      invoke its command procedure (Tcl_SetCmd) at runtime.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the incr command.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the "set" command
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileSetCmd(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    Proc *procPtr = envPtr->procPtr;
                                /* Points to structure describing procedure
                                 * containing the set command, else NULL. */
    ArgInfo argInfo;            /* Structure holding information about the
                                 * start and end of each argument word. */
    int simpleVarName;          /* 1 if name is just sequence of chars with
                                 * an optional element name in parens. */
    char *elName = NULL;        /* If simpleVarName, points to first char of
                                 * element name and elNameChars is length.
                                 * Otherwise NULL. */
    int isAssignment;           /* 1 if assigning value to var, else 0. */
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to execute cmd. */
    int localIndex = -1;        /* Index of the variable in the current
                                 * procedure's array of local variables.
                                 * Otherwise -1 if not in a procedure, the
                                 * name contains "::"s, or the variable
                                 * wasn't found. */
    char savedChar;             /* Holds the character from string
                                 * termporarily replaced by a null char
                                 * during name processing. */
    int objIndex = -1;          /* The object array index for a pushed
                                 * object holding a name part. Initialized
                                 * to avoid a compiler warning. */
    char *wordStart, *p;
    int numWords, isCompilableInt, i, result;
    Tcl_Obj *objPtr;
    int savePushSimpleWords = envPtr->pushSimpleWords;
 
    /*
     * Scan the words of the command and record the start and finish of
     * each argument word.
     */
 
    InitArgInfo(&argInfo);
    result = CollectArgInfo(interp, string, lastChar, flags, &argInfo);
    numWords = argInfo.numArgs;   /* i.e., the # after the command name */
    if (result != TCL_OK) {
        goto done;
    }
    if ((numWords < 1) || (numWords > 2)) {
        Tcl_ResetResult(interp);
        Tcl_AppendToObj(Tcl_GetObjResult(interp),
                "wrong # args: should be \"set varName ?newValue?\"", -1);
        result = TCL_ERROR;
        goto done;
    }
    isAssignment = (numWords == 2);
 
    /*
     * Parse the next word: the variable name. If the name is enclosed in
     * quotes or braces, we return TCL_OUT_LINE_COMPILE and call the set
     * command procedure at runtime since this makes sure that a second
     * round of substitutions is done properly.
     */
 
    wordStart = argInfo.startArray[0]; /* start of 1st arg word: varname */
    if ((*wordStart == '{') || (*wordStart == '"')) {
        result = TCL_OUT_LINE_COMPILE;
        goto done;
    }
 
    /*
     * Check whether the name is "simple": requires no substitutions at
     * runtime.
     */
 
    envPtr->pushSimpleWords = 0;
    result = CompileWord(interp, wordStart, argInfo.endArray[0] + 1,
            flags, envPtr);
    if (result != TCL_OK) {
        goto done;
    }
    simpleVarName = envPtr->wordIsSimple;
 
    if (!simpleVarName) {
        /*
         * The name isn't simple. CompileWord already pushed it.
         */
 
        maxDepth = envPtr->maxStackDepth;
    } else {
        char *name;             /* If simpleVarName, points to first char of
                                 * variable name and nameChars is length.
                                 * Otherwise NULL. */
        int nameChars;          /* Length of the var name. */
        int nameHasNsSeparators = 0;
                                /* Set 1 if name contains "::"s. */
        int elNameChars;        /* Length of array's element name if any. */
 
        /*
         * A simple name. First divide it up into "name" plus "elName"
         * for an array element name, if any.
         */
 
        name = wordStart;
        nameChars = envPtr->numSimpleWordChars;
        elName = NULL;
        elNameChars = 0;
 
        p = name;
        for (i = 0;  i < nameChars;  i++) {
            if (*p == '(') {
                char *openParen = p;
                p = (name + nameChars-1);
                if (*p == ')') { /* last char is ')' => array reference */
                    nameChars = (openParen - name);
                    elName = openParen+1;
                    elNameChars = (p - elName);
                }
                break;
            }
            p++;
        }
 
        /*
         * Determine if name has any namespace separators (::'s).
         */
 
        p = name;
        for (i = 0;  i < nameChars;  i++) {
            if ((*p == ':') && ((i+1) < nameChars) && (*(p+1) == ':')) {
                nameHasNsSeparators = 1;
                break;
            }
            p++;
        }
 
        /*
         * Now either push the name or determine its index in the array of
         * local variables in a procedure frame. Note that if we are
         * compiling a procedure the variable must be local unless its
         * name has namespace separators ("::"s). Note also that global
         * variables are implemented by a local variable that "points" to
         * the real global. There are two cases:
         *   1) We are not compiling a procedure body. Push the global
         *      variable's name and do the lookup at runtime.
         *   2) We are compiling a procedure and the name has "::"s.
         *      Push the namespace variable's name and do the lookup at
         *      runtime.
         *   3) We are compiling a procedure and the name has no "::"s.
         *      If the variable has already been allocated an local index,
         *      just look it up. If the variable is unknown and we are
         *      doing an assignment, allocate a new index. Otherwise,
         *      push the name and try to do the lookup at runtime.
         */
 
        if ((procPtr == NULL) || nameHasNsSeparators) {
            savedChar = name[nameChars];
            name[nameChars] = '\0';
            objIndex = TclObjIndexForString(name, nameChars,
                    /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
            name[nameChars] = savedChar;
            TclEmitPush(objIndex, envPtr);
            maxDepth = 1;
        } else {
            localIndex = LookupCompiledLocal(name, nameChars,
                    /*createIfNew*/ isAssignment,
                    /*flagsIfCreated*/
                        ((elName == NULL)? VAR_SCALAR : VAR_ARRAY),
                    envPtr->procPtr);
            if (localIndex >= 0) {
                maxDepth = 0;
            } else {
                savedChar = name[nameChars];
                name[nameChars] = '\0';
                objIndex = TclObjIndexForString(name, nameChars,
                        /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
                name[nameChars] = savedChar;
                TclEmitPush(objIndex, envPtr);
                maxDepth = 1;
            }
        }
 
        /*
         * If we are dealing with a reference to an array element, push the
         * array element. Perform substitutions on it, just as is done
         * for quoted strings.
         */
 
        if (elName != NULL) {
            savedChar = elName[elNameChars];
            elName[elNameChars] = '\0';
            envPtr->pushSimpleWords = 1;
            result = TclCompileQuotes(interp, elName, elName+elNameChars,
                    0, flags, envPtr);
            elName[elNameChars] = savedChar;
            if (result != TCL_OK) {
                char msg[200];
                sprintf(msg, "\n    (parsing index for array \"%.*s\")",
                        TclMin(nameChars, 100), name);
                Tcl_AddObjErrorInfo(interp, msg, -1);
                goto done;
            }
            maxDepth += envPtr->maxStackDepth;
        }
    }
 
    /*
     * If we are doing an assignment, push the new value.
     */
 
    if (isAssignment) {
        wordStart = argInfo.startArray[1]; /* start of 2nd arg word */
        envPtr->pushSimpleWords = 0;       /* we will handle simple words */
        result = CompileWord(interp, wordStart, argInfo.endArray[1] + 1,
                flags, envPtr);
        if (result != TCL_OK) {
            goto done;
        }
        if (!envPtr->wordIsSimple) {
            /*
             * The value isn't simple. CompileWord already pushed it.
             */
 
            maxDepth += envPtr->maxStackDepth;
        } else {
            /*
             * The value is simple. See if the word represents an integer
             * whose formatted representation is the same as the word (e.g.,
             * this is true for 123 and -1 but not for 00005). If so, just
             * push an integer object.
             */
 
            char buf[40];
            long n;
 
            p = wordStart;
            if ((*wordStart == '"') || (*wordStart == '{')) {
                p++;
            }
            savedChar = p[envPtr->numSimpleWordChars];
            p[envPtr->numSimpleWordChars] = '\0';
            isCompilableInt = 0;
            if (TclLooksLikeInt(p)) {
                int code = TclGetLong(interp, p, &n);
                if (code == TCL_OK) {
                    TclFormatInt(buf, n);
                    if (strcmp(p, buf) == 0) {
                        isCompilableInt = 1;
                        objIndex = TclObjIndexForString(p,
                                envPtr->numSimpleWordChars,
                                /*allocStrRep*/ 0, /*inHeap*/ 0, envPtr);
                        objPtr = envPtr->objArrayPtr[objIndex];
 
                        Tcl_InvalidateStringRep(objPtr);
                        objPtr->internalRep.longValue = n;
                        objPtr->typePtr = &tclIntType;
                    }
                } else {
                    Tcl_ResetResult(interp);
                }
            }
            if (!isCompilableInt) {
                objIndex = TclObjIndexForString(p,
                        envPtr->numSimpleWordChars, /*allocStrRep*/ 1,
                        /*inHeap*/ 0, envPtr);
            }
            p[envPtr->numSimpleWordChars] = savedChar;
            TclEmitPush(objIndex, envPtr);
            maxDepth += 1;
        }
    }
 
    /*
     * Now emit instructions to set/retrieve the variable.
     */
 
    if (simpleVarName) {
        if (elName == NULL) {  /* scalar */
            if (localIndex >= 0) {
                if (localIndex <= 255) {
                    TclEmitInstUInt1((isAssignment?
                             INST_STORE_SCALAR1 : INST_LOAD_SCALAR1),
                        localIndex, envPtr);
                } else {
                    TclEmitInstUInt4((isAssignment?
                             INST_STORE_SCALAR4 : INST_LOAD_SCALAR4),
                        localIndex, envPtr);
                }
            } else {
                TclEmitOpcode((isAssignment?
                             INST_STORE_SCALAR_STK : INST_LOAD_SCALAR_STK),
                            envPtr);
            }
        } else {                /* array */
            if (localIndex >= 0) {
                if (localIndex <= 255) {
                    TclEmitInstUInt1((isAssignment?
                             INST_STORE_ARRAY1 : INST_LOAD_ARRAY1),
                        localIndex, envPtr);
                } else {
                    TclEmitInstUInt4((isAssignment?
                             INST_STORE_ARRAY4 : INST_LOAD_ARRAY4),
                        localIndex, envPtr);
                }
            } else {
                TclEmitOpcode((isAssignment?
                             INST_STORE_ARRAY_STK : INST_LOAD_ARRAY_STK),
                            envPtr);
            }
        }
    } else {                    /* non-simple variable name */
        TclEmitOpcode((isAssignment? INST_STORE_STK : INST_LOAD_STK), envPtr);
    }
 
    done:
    if (numWords == 0) {
        envPtr->termOffset = 0;
    } else {
        envPtr->termOffset = (argInfo.endArray[numWords-1] + 1 - string);
    }
    envPtr->pushSimpleWords = savePushSimpleWords;
    envPtr->maxStackDepth = maxDepth;
    FreeArgInfo(&argInfo);
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCompileWhileCmd --
 *
 *      Procedure called to compile the "while" command.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK if
 *      compilation was successful. If an error occurs then the
 *      interpreter's result contains a standard error message and TCL_ERROR
 *      is returned. If compilation failed because the command is too
 *      complex for TclCompileWhileCmd, TCL_OUT_LINE_COMPILE is returned
 *      indicating that the while command should be compiled "out of line"
 *      by emitting code to invoke its command procedure at runtime.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the "while" command.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the "while" command
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCompileWhileCmd(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;              /* Pointer to terminating character of
                                  * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    register char *src = string;/* Points to current source char. */
    register int type;          /* Current char's CHAR_TYPE type. */
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to execute cmd. */
    int range = -1;             /* Index in the ExceptionRange array of the
                                 * ExceptionRange record for this loop. */
    JumpFixup jumpFalseFixup;   /* Used to update or replace the ifFalse
                                 * jump after test when its target PC is
                                 * determined. */
    unsigned char *jumpPc;
    int jumpDist, jumpBackDist, jumpBackOffset, objIndex, result;
    int savePushSimpleWords = envPtr->pushSimpleWords;
 
    AdvanceToNextWord(src, envPtr);
    src += envPtr->termOffset;
    type = CHAR_TYPE(src, lastChar);
    if (type == TCL_COMMAND_END) {
        badArgs:
        Tcl_ResetResult(interp);
        Tcl_AppendToObj(Tcl_GetObjResult(interp),
                "wrong # args: should be \"while test command\"", -1);
        result = TCL_ERROR;
        goto done;
    }
 
    /*
     * If the test expression is not enclosed in braces, don't compile
     * the while inline. As a result of Tcl's two level substitution
     * semantics for expressions, the expression might have a constant
     * value that results in the loop never executing, or executing forever.
     * Consider "set x 0; whie "$x > 5" {incr x}": the loop body
     * should never be executed.
     * NOTE: This is an overly aggressive test, since there are legitimate
     * literals that could be compiled but aren't in braces.  However, until
     * the parser is integrated in 8.1, this is the simplest implementation.
     */
 
    if (*src != '{') {
        result = TCL_OUT_LINE_COMPILE;
        goto done;
    }
 
    /*
     * Create and initialize a ExceptionRange record to hold information
     * about this loop. This is used to implement break and continue.
     */
 
    envPtr->excRangeDepth++;
    envPtr->maxExcRangeDepth =
        TclMax(envPtr->excRangeDepth, envPtr->maxExcRangeDepth);
 
    range = CreateExceptionRange(LOOP_EXCEPTION_RANGE, envPtr);
    envPtr->excRangeArrayPtr[range].continueOffset = TclCurrCodeOffset();
 
    /*
     * Compile the next word: the test expression.
     */
 
    envPtr->pushSimpleWords = 1;
    result = CompileExprWord(interp, src, lastChar, flags, envPtr);
    if (result != TCL_OK) {
        if (result == TCL_ERROR) {
            Tcl_AddObjErrorInfo(interp,
                    "\n    (\"while\" test expression)", -1);
        }
        goto done;
    }
    maxDepth = envPtr->maxStackDepth;
    src += envPtr->termOffset;
 
    /*
     * Emit the ifFalse jump that terminates the while if the test was
     * false. We emit a one byte (relative) jump here, and replace it
     * later with a four byte jump if the jump target is more than
     * 127 bytes away.
     */
 
    TclEmitForwardJump(envPtr, TCL_FALSE_JUMP, &jumpFalseFixup);
 
    /*
     * Compile the loop body word inline. Also register the loop body's
     * starting PC offset and byte length in the its ExceptionRange record.
     */
 
    AdvanceToNextWord(src, envPtr);
    src += envPtr->termOffset;
    type = CHAR_TYPE(src, lastChar);
    if (type == TCL_COMMAND_END) {
        goto badArgs;
    }
 
    envPtr->excRangeArrayPtr[range].codeOffset = TclCurrCodeOffset();
    result = CompileCmdWordInline(interp, src, lastChar,
            flags, envPtr);
    if (result != TCL_OK) {
        if (result == TCL_ERROR) {
            char msg[60];
            sprintf(msg, "\n    (\"while\" body line %d)", interp->errorLine);
            Tcl_AddObjErrorInfo(interp, msg, -1);
        }
        goto done;
    }
    maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
    src += envPtr->termOffset;
    envPtr->excRangeArrayPtr[range].numCodeBytes =
        (TclCurrCodeOffset() - envPtr->excRangeArrayPtr[range].codeOffset);
 
    /*
     * Discard the loop body's result.
     */
 
    TclEmitOpcode(INST_POP, envPtr);
 
    /*
     * Emit the unconditional jump back to the test at the top of the
     * loop. We generate a four byte jump if the distance to the while's
     * test is greater than 120 bytes. This is conservative, and ensures
     * that we won't have to replace this unconditional jump if we later
     * need to replace the ifFalse jump with a four-byte jump.
     */
 
    jumpBackOffset = TclCurrCodeOffset();
    jumpBackDist =
        (jumpBackOffset - envPtr->excRangeArrayPtr[range].continueOffset);
    if (jumpBackDist > 120) {
        TclEmitInstInt4(INST_JUMP4, /*offset*/ -jumpBackDist, envPtr);
    } else {
        TclEmitInstInt1(INST_JUMP1, /*offset*/ -jumpBackDist, envPtr);
    }
 
    /*
     * Now that we know the target of the jumpFalse after the test, update
     * it with the correct distance. If the distance is too great (more
     * than 127 bytes), replace that jump with a four byte instruction and
     * move the instructions after the jump down.
     */
 
    jumpDist = (TclCurrCodeOffset() - jumpFalseFixup.codeOffset);
    if (TclFixupForwardJump(envPtr, &jumpFalseFixup, jumpDist, 127)) {
        /*
         * Update the loop body's starting PC offset since it moved down.
         */
 
        envPtr->excRangeArrayPtr[range].codeOffset += 3;
 
        /*
         * Update the distance for the unconditional jump back to the test
         * at the top of the loop since it moved down 3 bytes too.
         */
 
        jumpBackOffset += 3;
        jumpPc = (envPtr->codeStart + jumpBackOffset);
        if (jumpBackDist > 120) {
            jumpBackDist += 3;
            TclUpdateInstInt4AtPc(INST_JUMP4, /*offset*/ -jumpBackDist,
                                   jumpPc);
        } else {
            jumpBackDist += 3;
            TclUpdateInstInt1AtPc(INST_JUMP1, /*offset*/ -jumpBackDist,
                                   jumpPc);
        }
    }
 
    /*
     * The current PC offset (after the loop's body) is the loop's
     * break target.
     */
 
    envPtr->excRangeArrayPtr[range].breakOffset = TclCurrCodeOffset();
 
    /*
     * Push an empty string object as the while command's result.
     */
 
    objIndex = TclObjIndexForString("", 0, /*allocStrRep*/ 0, /*inHeap*/ 0,
                                    envPtr);
    TclEmitPush(objIndex, envPtr);
    if (maxDepth == 0) {
        maxDepth = 1;
    }
 
    /*
     * Skip over white space until the end of the command.
     */
 
    type = CHAR_TYPE(src, lastChar);
    if (type != TCL_COMMAND_END) {
        AdvanceToNextWord(src, envPtr);
        src += envPtr->termOffset;
        type = CHAR_TYPE(src, lastChar);
        if (type != TCL_COMMAND_END) {
            goto badArgs;
        }
    }
 
    done:
    envPtr->termOffset = (src - string);
    envPtr->pushSimpleWords = savePushSimpleWords;
    envPtr->maxStackDepth = maxDepth;
    if (range != -1) {
        envPtr->excRangeDepth--;
    }
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * CompileExprWord --
 *
 *      Procedure that compiles a Tcl expression in a command word.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK unless
 *      there was an error while compiling string. If an error occurs then
 *      the interpreter's result contains a standard error message.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the "expr" word.
 *
 * Side effects:
 *      Instructions are added to envPtr to evaluate the expression word
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
static int
CompileExprWord(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;              /* Pointer to terminating character of
                                  * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    register char *src = string;/* Points to current source char. */
    register int type;          /* Current char's CHAR_TYPE type. */
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to execute the expression. */
    int nestedCmd = (flags & TCL_BRACKET_TERM);
                                /* 1 if script being compiled is a nested
                                 * command and is terminated by a ']';
                                 * otherwise 0. */
    char *first, *last;         /* Points to the first and last significant
                                 * characters of the word. */
    char savedChar;             /* Holds the character termporarily replaced
                                 * by a null character during compilation
                                 * of the expression. */
    int inlineCode;             /* 1 if inline "optimistic" code is
                                 * emitted for the expression; else 0. */
    int range = -1;             /* If we inline compile an un-{}'d
                                 * expression, the index for its catch range
                                 * record in the ExceptionRange array.
                                 * Initialized to enable proper cleanup. */
    JumpFixup jumpFixup;        /* Used to emit the "success" jump after
                                 * the inline expression code. */
    char *p;
    char c;
    int savePushSimpleWords = envPtr->pushSimpleWords;
    int saveExprIsJustVarRef = envPtr->exprIsJustVarRef;
    int saveExprIsComparison = envPtr->exprIsComparison;
    int numChars, result;
 
    /*
     * Skip over leading white space.
     */
 
    AdvanceToNextWord(src, envPtr);
    src += envPtr->termOffset;
    type = CHAR_TYPE(src, lastChar);
    if (type == TCL_COMMAND_END) {
        badArgs:
        Tcl_ResetResult(interp);
            Tcl_AppendToObj(Tcl_GetObjResult(interp),
                    "malformed expression word", -1);
        result = TCL_ERROR;
        goto done;
    }
 
    /*
     * If the word is enclosed in {}s, we may strip them off and safely
     * compile the expression into an inline sequence of instructions using
     * TclCompileExpr. We know these instructions will have the right Tcl7.x
     * expression semantics.
     *
     * Otherwise, if the word is not enclosed in {}s, we may need to call
     * the expr command (Tcl_ExprObjCmd) at runtime. This recompiles the
     * expression each time (typically) and so is slow. However, there are
     * some circumstances where we can still compile inline instructions
     * "optimistically" and check, during their execution, for double
     * substitutions (these appear as nonnumeric operands). We check for any
     * backslash or command substitutions. If none appear, and only variable
     * substitutions are found, we generate inline instructions.
     *
     * For now, if the expression is not enclosed in {}s, we call the expr
     * command at runtime if either command or backslash substitutions
     * appear (but not if only variable substitutions appear).
     */
 
    if (*src == '{') {
        /*
         * Inline compile the expression inside {}s.
         */
 
        first = src+1;
        src = TclWordEnd(src, lastChar, nestedCmd, NULL);
        if (*src == 0) {
            goto badArgs;
        }
        if (*src != '}') {
            goto badArgs;
        }
        last = (src-1);
 
        numChars = (last - first + 1);
        savedChar = first[numChars];
        first[numChars] = '\0';
        result = TclCompileExpr(interp, first, first+numChars,
                flags, envPtr);
        first[numChars] = savedChar;
 
        src++;
        maxDepth = envPtr->maxStackDepth;
    } else {
        /*
         * No braces. If the expression is enclosed in '"'s, call the expr
         * cmd at runtime. Otherwise, scan the word's characters looking for
         * any '['s or (for now) '\'s. If any are found, just call expr cmd
         * at runtime.
         */
 
        first = src;
        last = TclWordEnd(first, lastChar, nestedCmd, NULL);
        if (*last == 0) {        /* word doesn't end properly. */
            src = last;
            goto badArgs;
        }
 
        inlineCode = 1;
        if ((*first == '"') && (*last == '"')) {
            inlineCode = 0;
        } else {
            for (p = first;  p <= last;  p++) {
                c = *p;
                if ((c == '[') || (c == '\\')) {
                    inlineCode = 0;
                    break;
                }
            }
        }
 
        if (inlineCode) {
            /*
             * Inline compile the expression inside a "catch" so that a
             * runtime error will back off to make a (slow) call on expr.
             */
 
            int startCodeOffset = (envPtr->codeNext - envPtr->codeStart);
            int startRangeNext = envPtr->excRangeArrayNext;
 
            /*
             * Create a ExceptionRange record to hold information about
             * the "catch" range for the expression's inline code. Also
             * emit the instruction to mark the start of the range.
             */
 
            envPtr->excRangeDepth++;
            envPtr->maxExcRangeDepth =
                TclMax(envPtr->excRangeDepth, envPtr->maxExcRangeDepth);
            range = CreateExceptionRange(CATCH_EXCEPTION_RANGE, envPtr);
            TclEmitInstUInt4(INST_BEGIN_CATCH4, range, envPtr);
 
            /*
             * Inline compile the expression.
             */
 
            envPtr->excRangeArrayPtr[range].codeOffset = TclCurrCodeOffset();
            numChars = (last - first + 1);
            savedChar = first[numChars];
            first[numChars] = '\0';
            result = TclCompileExpr(interp, first, first + numChars,
                    flags, envPtr);
            first[numChars] = savedChar;
 
            envPtr->excRangeArrayPtr[range].numCodeBytes =
                TclCurrCodeOffset() - envPtr->excRangeArrayPtr[range].codeOffset;
 
            if ((result != TCL_OK) || (envPtr->exprIsJustVarRef)
                    || (envPtr->exprIsComparison)) {
                /*
                 * We must call the expr command at runtime. Either there
                 * was a compilation error or the inline code might fail to
                 * give the correct 2 level substitution semantics.
                 *
                 * The latter can happen if the expression consisted of just
                 * a single variable reference or if the top-level operator
                 * in the expr is a comparison (which might operate on
                 * strings). In the latter case, the expression's code might
                 * execute (apparently) successfully but produce the wrong
                 * result. We depend on its execution failing if a second
                 * level of substitutions is required. This causes the
                 * "catch" code we generate around the inline code to back
                 * off to a call on the expr command at runtime, and this
                 * always gives the right 2 level substitution semantics.
                 *
                 * We delete the inline code by backing up the code pc and
                 * catch index. Note that if there was a compilation error,
                 * we can't report the error yet since the expression might
                 * be valid after the second round of substitutions.
                 */
 
                envPtr->codeNext = (envPtr->codeStart + startCodeOffset);
                envPtr->excRangeArrayNext = startRangeNext;
                inlineCode = 0;
            } else {
                TclEmitOpcode(INST_END_CATCH, envPtr);
                TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &jumpFixup);
                envPtr->excRangeArrayPtr[range].catchOffset = TclCurrCodeOffset();
            }
        }
 
        /*
         * Arrange to call expr at runtime with the (already substituted
         * once) expression word on the stack.
         */
 
        envPtr->pushSimpleWords = 1;
        result = CompileWord(interp, first, lastChar, flags, envPtr);
        src += envPtr->termOffset;
        maxDepth = envPtr->maxStackDepth;
        if (result == TCL_OK) {
            TclEmitOpcode(INST_EXPR_STK, envPtr);
        }
 
        /*
         * If emitting inline code for this non-{}'d expression, update
         * the target of the jump after that inline code.
         */
 
        if (inlineCode) {
            int jumpDist = (TclCurrCodeOffset() - jumpFixup.codeOffset);
            if (TclFixupForwardJump(envPtr, &jumpFixup, jumpDist, 127)) {
                /*
                 * Update the inline expression code's catch ExceptionRange
                 * target since it, being after the jump, also moved down.
                 */
 
                envPtr->excRangeArrayPtr[range].catchOffset += 3;
            }
        }
    } /* if expression isn't in {}s */
 
    done:
    if (range != -1) {
        envPtr->excRangeDepth--;
    }
    envPtr->termOffset = (src - string);
    envPtr->maxStackDepth = maxDepth;
    envPtr->pushSimpleWords = savePushSimpleWords;
    envPtr->exprIsJustVarRef = saveExprIsJustVarRef;
    envPtr->exprIsComparison = saveExprIsComparison;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * CompileCmdWordInline --
 *
 *      Procedure that compiles a Tcl command word inline. If the word is
 *      enclosed in quotes or braces, we call TclCompileString to compile it
 *      after stripping them off. Otherwise, we normally push the word's
 *      value and call eval at runtime, but if the word is just a sequence
 *      of alphanumeric characters, we emit an invoke instruction
 *      directly. This procedure assumes that string points to the start of
 *      the word to compile.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK unless
 *      there was an error while compiling string. If an error occurs then
 *      the interpreter's result contains a standard error message.
 *
 *      envPtr->termOffset is filled in with the offset of the character in
 *      "string" just after the last one successfully processed.
 *
 *      envPtr->maxStackDepth is updated with the maximum number of stack
 *      elements needed to execute the command.
 *
 * Side effects:
 *      Instructions are added to envPtr to execute the command word
 *      at runtime.
 *
 *----------------------------------------------------------------------
 */
 
static int
CompileCmdWordInline(interp, string, lastChar, flags, envPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source string to compile. */
    char *lastChar;             /* Pointer to terminating character of
                                 * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    Interp *iPtr = (Interp *) interp;
    register char *src = string;/* Points to current source char. */
    register int type;          /* Current char's CHAR_TYPE type. */
    int maxDepth = 0;            /* Maximum number of stack elements needed
                                 * to execute cmd. */
    char *termPtr;              /* Points to char that terminated braced
                                 * string. */
    char savedChar;             /* Holds the character termporarily replaced
                                 * by a null character during compilation
                                 * of the command. */
    int savePushSimpleWords = envPtr->pushSimpleWords;
    int objIndex;
    int result = TCL_OK;
    register char c;
 
    type = CHAR_TYPE(src, lastChar);
    if (type & (TCL_QUOTE | TCL_OPEN_BRACE)) {
        src++;
        envPtr->pushSimpleWords = 0;
        if (type == TCL_QUOTE) {
            result = TclCompileQuotes(interp, src, lastChar,
                    '"', flags, envPtr);
        } else {
            result = CompileBraces(interp, src, lastChar, flags, envPtr);
        }
        if (result != TCL_OK) {
            goto done;
        }
 
        /*
         * Make sure the terminating character is the end of word.
         */
 
        termPtr = (src + envPtr->termOffset);
        c = *termPtr;
        if ((c == '\\') && (*(termPtr+1) == '\n')) {
            /*
             * Line is continued on next line; the backslash-newline turns
             * into space, which terminates the word.
             */
        } else {
            type = CHAR_TYPE(termPtr, lastChar);
            if ((type != TCL_SPACE) && (type != TCL_COMMAND_END)) {
                Tcl_ResetResult(interp);
                if (*(src-1) == '"') {
                    Tcl_AppendToObj(Tcl_GetObjResult(interp),
                            "extra characters after close-quote", -1);
                } else {
                    Tcl_AppendToObj(Tcl_GetObjResult(interp),
                            "extra characters after close-brace", -1);
                }
                result = TCL_ERROR;
                goto done;
            }
        }
 
        if (envPtr->wordIsSimple) {
            /*
             * A simple word enclosed in "" or {}s. Call TclCompileString to
             * compile it inline. Add a null character after the end of the
             * quoted or braced string: i.e., at the " or }. Turn the
             * flag bit TCL_BRACKET_TERM off since the recursively
             * compiled subcommand is now terminated by a null character.
             */
            char *closeCharPos = (termPtr - 1);
 
            savedChar = *closeCharPos;
            *closeCharPos = '\0';
            result = TclCompileString(interp, src, closeCharPos,
                    (flags & ~TCL_BRACKET_TERM), envPtr);
            *closeCharPos = savedChar;
            if (result != TCL_OK) {
                goto done;
            }
        } else {
            /*
             * The braced string contained a backslash-newline. Call eval
             * at runtime.
             */
            TclEmitOpcode(INST_EVAL_STK, envPtr);
        }
        src = termPtr;
        maxDepth = envPtr->maxStackDepth;
    } else {
        /*
         * Not a braced or quoted string. We normally push the word's
         * value and call eval at runtime. However, if the word is just
         * a sequence of alphanumeric characters, we call its compile
         * procedure, if any, or otherwise just emit an invoke instruction.
         */
 
        char *p = src;
        c = *p;
        while (isalnum(UCHAR(c)) || (c == '_')) {
            p++;
            c = *p;
        }
        type = CHAR_TYPE(p, lastChar);
        if ((p > src) && (type == TCL_COMMAND_END)) {
            /*
             * Look for a compile procedure and call it. Otherwise emit an
             * invoke instruction to call the command at runtime.
             */
 
            Tcl_Command cmd;
            Command *cmdPtr = NULL;
            int wasCompiled = 0;
 
            savedChar = *p;
            *p = '\0';
 
            cmd = Tcl_FindCommand(interp, src, (Tcl_Namespace *) NULL,
                    /*flags*/ 0);
            if (cmd != (Tcl_Command) NULL) {
                cmdPtr = (Command *) cmd;
            }
            if (cmdPtr != NULL && cmdPtr->compileProc != NULL) {
                *p = savedChar;
                src = p;
                iPtr->flags &= ~(ERR_ALREADY_LOGGED | ERR_IN_PROGRESS
                                 | ERROR_CODE_SET);
                result = (*(cmdPtr->compileProc))(interp, src, lastChar, flags, envPtr);
                if (result != TCL_OK) {
                    goto done;
                }
                wasCompiled = 1;
                src += envPtr->termOffset;
                maxDepth = envPtr->maxStackDepth;
            }
            if (!wasCompiled) {
                objIndex = TclObjIndexForString(src, p-src,
                        /*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
                *p = savedChar;
                TclEmitPush(objIndex, envPtr);
                TclEmitInstUInt1(INST_INVOKE_STK1, 1, envPtr);
                src = p;
                maxDepth = 1;
            }
        } else {
            /*
             * Push the word and call eval at runtime.
             */
 
            envPtr->pushSimpleWords = 1;
            result = CompileWord(interp, src, lastChar, flags, envPtr);
            if (result != TCL_OK) {
                goto done;
            }
            TclEmitOpcode(INST_EVAL_STK, envPtr);
            src += envPtr->termOffset;
            maxDepth = envPtr->maxStackDepth;
        }
    }
 
    done:
    envPtr->termOffset = (src - string);
    envPtr->maxStackDepth = maxDepth;
    envPtr->pushSimpleWords = savePushSimpleWords;
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * LookupCompiledLocal --
 *
 *      This procedure is called at compile time to look up and optionally
 *      allocate an entry ("slot") for a variable in a procedure's array of
 *      local variables. If the variable's name is NULL, a new temporary
 *      variable is always created. (Such temporary variables can only be
 *      referenced using their slot index.)
 *
 * Results:
 *      If createIfNew is 0 (false) and the name is non-NULL, then if the
 *      variable is found, the index of its entry in the procedure's array
 *      of local variables is returned; otherwise -1 is returned.
 *      If name is NULL, the index of a new temporary variable is returned.
 *      Finally, if createIfNew is 1 and name is non-NULL, the index of a
 *      new entry is returned.
 *
 * Side effects:
 *      Creates and registers a new local variable if createIfNew is 1 and
 *      the variable is unknown, or if the name is NULL.
 *
 *----------------------------------------------------------------------
 */
 
static int
LookupCompiledLocal(name, nameChars, createIfNew, flagsIfCreated, procPtr)
    register char *name;        /* Points to first character of the name of
                                 * a scalar or array variable. If NULL, a
                                 * temporary var should be created. */
    int nameChars;              /* The length of the name excluding the
                                 * terminating null character. */
    int createIfNew;            /* 1 to allocate a local frame entry for the
                                 * variable if it is new. */
    int flagsIfCreated;         /* Flag bits for the compiled local if
                                 * created. Only VAR_SCALAR, VAR_ARRAY, and
                                 * VAR_LINK make sense. */
    register Proc *procPtr;     /* Points to structure describing procedure
                                 * containing the variable reference. */
{
    register CompiledLocal *localPtr;
    int localIndex = -1;
    register int i;
    int localCt;
 
    /*
     * If not creating a temporary, does a local variable of the specified
     * name already exist?
     */
 
    if (name != NULL) {
        localCt = procPtr->numCompiledLocals;
        localPtr = procPtr->firstLocalPtr;
        for (i = 0;  i < localCt;  i++) {
            if (!TclIsVarTemporary(localPtr)) {
                char *localName = localPtr->name;
                if ((name[0] == localName[0])
                        && (nameChars == localPtr->nameLength)
                        && (strncmp(name, localName, (unsigned) nameChars) == 0)) {
                    return i;
                }
            }
            localPtr = localPtr->nextPtr;
        }
    }
 
    /*
     * Create a new variable if appropriate.
     */
 
    if (createIfNew || (name == NULL)) {
        localIndex = procPtr->numCompiledLocals;
        localPtr = (CompiledLocal *) ckalloc((unsigned)
                (sizeof(CompiledLocal) - sizeof(localPtr->name)
                + nameChars+1));
        if (procPtr->firstLocalPtr == NULL) {
            procPtr->firstLocalPtr = procPtr->lastLocalPtr = localPtr;
        } else {
            procPtr->lastLocalPtr->nextPtr = localPtr;
            procPtr->lastLocalPtr = localPtr;
        }
        localPtr->nextPtr = NULL;
        localPtr->nameLength = nameChars;
        localPtr->frameIndex = localIndex;
        localPtr->flags = flagsIfCreated;
        if (name == NULL) {
            localPtr->flags |= VAR_TEMPORARY;
        }
        localPtr->defValuePtr = NULL;
        localPtr->resolveInfo = NULL;
 
        if (name != NULL) {
            memcpy((VOID *) localPtr->name, (VOID *) name, (size_t) nameChars);
        }
        localPtr->name[nameChars] = '\0';
        procPtr->numCompiledLocals++;
    }
    return localIndex;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclInitCompiledLocals --
 *
 *      This routine is invoked in order to initialize the compiled
 *      locals table for a new call frame.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      May invoke various name resolvers in order to determine which
 *      variables are being referenced at runtime.
 *
 *----------------------------------------------------------------------
 */
 
void
TclInitCompiledLocals(interp, framePtr, nsPtr)
    Tcl_Interp *interp;         /* Current interpreter. */
    CallFrame *framePtr;        /* Call frame to initialize. */
    Namespace *nsPtr;           /* Pointer to current namespace. */
{
    register CompiledLocal *localPtr;
    Interp *iPtr = (Interp*) interp;
    Tcl_ResolvedVarInfo *vinfo, *resVarInfo;
    Var *varPtr = framePtr->compiledLocals;
    Var *resolvedVarPtr;
    ResolverScheme *resPtr;
    int result;
 
    /*
     * Initialize the array of local variables stored in the call frame.
     * Some variables may have special resolution rules.  In that case,
     * we call their "resolver" procs to get our hands on the variable,
     * and we make the compiled local a link to the real variable.
     */
 
    for (localPtr = framePtr->procPtr->firstLocalPtr;
         localPtr != NULL;
         localPtr = localPtr->nextPtr) {
 
        /*
         * Check to see if this local is affected by namespace or
         * interp resolvers.  The resolver to use is cached for the
         * next invocation of the procedure.
         */
 
        if (!(localPtr->flags & (VAR_ARGUMENT|VAR_TEMPORARY|VAR_RESOLVED))
                && (nsPtr->compiledVarResProc || iPtr->resolverPtr)) {
            resPtr = iPtr->resolverPtr;
 
            if (nsPtr->compiledVarResProc) {
                result = (*nsPtr->compiledVarResProc)(nsPtr->interp,
                        localPtr->name, localPtr->nameLength,
                        (Tcl_Namespace *) nsPtr, &vinfo);
            } else {
                result = TCL_CONTINUE;
            }
 
            while ((result == TCL_CONTINUE) && resPtr) {
                if (resPtr->compiledVarResProc) {
                    result = (*resPtr->compiledVarResProc)(nsPtr->interp,
                            localPtr->name, localPtr->nameLength,
                            (Tcl_Namespace *) nsPtr, &vinfo);
                }
                resPtr = resPtr->nextPtr;
            }
            if (result == TCL_OK) {
                localPtr->resolveInfo = vinfo;
                localPtr->flags |= VAR_RESOLVED;
            }
        }
 
        /*
         * Now invoke the resolvers to determine the exact variables that
         * should be used.
         */
 
        resVarInfo = localPtr->resolveInfo;
        resolvedVarPtr = NULL;
 
        if (resVarInfo && resVarInfo->fetchProc) {
            resolvedVarPtr = (Var*) (*resVarInfo->fetchProc)(interp,
                resVarInfo);
        }
 
        if (resolvedVarPtr) {
            varPtr->name = localPtr->name; /* will be just '\0' if temp var */
            varPtr->nsPtr = NULL;
            varPtr->hPtr = NULL;
            varPtr->refCount = 0;
            varPtr->tracePtr = NULL;
            varPtr->searchPtr = NULL;
            varPtr->flags = 0;
            TclSetVarLink(varPtr);
            varPtr->value.linkPtr = resolvedVarPtr;
            resolvedVarPtr->refCount++;
        } else {
            varPtr->value.objPtr = NULL;
            varPtr->name = localPtr->name; /* will be just '\0' if temp var */
            varPtr->nsPtr = NULL;
            varPtr->hPtr = NULL;
            varPtr->refCount = 0;
            varPtr->tracePtr = NULL;
            varPtr->searchPtr = NULL;
            varPtr->flags = (localPtr->flags | VAR_UNDEFINED);
        }
        varPtr++;
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * AdvanceToNextWord --
 *
 *      This procedure is called to skip over any leading white space at the
 *      start of a word. Note that a backslash-newline is treated as a
 *      space.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Updates envPtr->termOffset with the offset of the first
 *      character in "string" that was not white space or a
 *      backslash-newline. This might be the offset of the character that
 *      ends the command: a newline, null, semicolon, or close-bracket.
 *
 *----------------------------------------------------------------------
 */
 
static void
AdvanceToNextWord(string, envPtr)
    char *string;               /* The source string to compile. */
    CompileEnv *envPtr;         /* Holds resulting instructions. */
{
    register char *src;         /* Points to current source char. */
    register int type;          /* Current char's CHAR_TYPE type. */
 
    src = string;
    type = CHAR_TYPE(src, src+1);
    while (type & (TCL_SPACE | TCL_BACKSLASH)) {
        if (type == TCL_BACKSLASH) {
            if (src[1] == '\n') {
                src += 2;
            } else {
                break;          /* exit loop; no longer white space */
            }
        } else {
            src++;
        }
        type = CHAR_TYPE(src, src+1);
    }
    envPtr->termOffset = (src - string);
}
 
/*
 *----------------------------------------------------------------------
 *
 * Tcl_Backslash --
 *
 *      Figure out how to handle a backslash sequence.
 *
 * Results:
 *      The return value is the character that should be substituted
 *      in place of the backslash sequence that starts at src.  If
 *      readPtr isn't NULL then it is filled in with a count of the
 *      number of characters in the backslash sequence.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
 
char
Tcl_Backslash(src, readPtr)
    CONST char *src;            /* Points to the backslash character of
                                 * a backslash sequence. */
    int *readPtr;               /* Fill in with number of characters read
                                 * from src, unless NULL. */
{
    CONST char *p = src + 1;
    char result;
    int count;
 
    count = 2;
 
    switch (*p) {
        /*
         * Note: in the conversions below, use absolute values (e.g.,
         * 0xa) rather than symbolic values (e.g. \n) that get converted
         * by the compiler.  It's possible that compilers on some
         * platforms will do the symbolic conversions differently, which
         * could result in non-portable Tcl scripts.
         */
 
        case 'a':
            result = 0x7;
            break;
        case 'b':
            result = 0x8;
            break;
        case 'f':
            result = 0xc;
            break;
        case 'n':
            result = 0xa;
            break;
        case 'r':
            result = 0xd;
            break;
        case 't':
            result = 0x9;
            break;
        case 'v':
            result = 0xb;
            break;
        case 'x':
            if (isxdigit(UCHAR(p[1]))) {
                char *end;
 
                result = (char) strtoul(p+1, &end, 16);
                count = end - src;
            } else {
                count = 2;
                result = 'x';
            }
            break;
        case '\n':
            do {
                p++;
            } while ((*p == ' ') || (*p == '\t'));
            result = ' ';
            count = p - src;
            break;
        case 0:
            result = '\\';
            count = 1;
            break;
        default:
            if (isdigit(UCHAR(*p))) {
                result = (char)(*p - '0');
                p++;
                if (!isdigit(UCHAR(*p))) {
                    break;
                }
                count = 3;
                result = (char)((result << 3) + (*p - '0'));
                p++;
                if (!isdigit(UCHAR(*p))) {
                    break;
                }
                count = 4;
                result = (char)((result << 3) + (*p - '0'));
                break;
            }
            result = *p;
            count = 2;
            break;
    }
 
    if (readPtr != NULL) {
        *readPtr = count;
    }
    return result;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclObjIndexForString --
 *
 *      Procedure to find, or if necessary create, an object in a
 *      CompileEnv's object array that has a string representation
 *      matching the argument string.
 *
 * Results:
 *      The index in the CompileEnv's object array of an object with a
 *      string representation matching the argument "string". The object is
 *      created if necessary. If inHeap is 1, then string is heap allocated
 *      and ownership of the string is passed to TclObjIndexForString;
 *      otherwise, the string is owned by the caller and must not be
 *      modified or freed by TclObjIndexForString. Typically, a caller sets
 *      inHeap 1 if string is an already heap-allocated buffer holding the
 *      result of backslash substitutions.
 *
 * Side effects:
 *      A new Tcl object will be created if no existing object matches the
 *      input string. If allocStrRep is 1 then if a new object is created,
 *      its string representation is allocated in the heap, else it is left
 *      NULL. If inHeap is 1, this procedure is given ownership of the
 *      string: if an object is created and allocStrRep is 1 then its
 *      string representation is set directly from string, otherwise
 *      the string is freed.
 *
 *----------------------------------------------------------------------
 */
 
int
TclObjIndexForString(string, length, allocStrRep, inHeap, envPtr)
    register char *string;      /* Points to string for which an object is
                                 * found or created in CompileEnv's object
                                 * array. */
    int length;                 /* Length of string. */
    int allocStrRep;            /* If 1 then the object's string rep should
                                 * be allocated in the heap. */
    int inHeap;                 /* If 1 then string is heap allocated and
                                 * its ownership is passed to
                                 * TclObjIndexForString. */
    CompileEnv *envPtr;         /* Points to the CompileEnv in whose object
                                 * array an object is found or created. */
{
    register Tcl_Obj *objPtr;   /* Points to the object created for
                                 * the string, if one was created. */
    int objIndex;               /* Index of matching object. */
    Tcl_HashEntry *hPtr;
    int strLength, new;
 
    /*
     * Look up the string in the code's object hashtable. If found, just
     * return the associated object array index.  Note that if the string
     * has embedded nulls, we don't create a hash table entry.  This
     * should be fixed, but we need to update hash tables, first.
     */
 
    strLength = strlen(string);
    if (length == -1) {
        length = strLength;
    }
    if (strLength != length) {
        hPtr = NULL;
    } else {
        hPtr = Tcl_CreateHashEntry(&envPtr->objTable, string, &new);
        if (!new) {             /* already in object table and array */
            objIndex = (int) Tcl_GetHashValue(hPtr);
            if (inHeap) {
                ckfree(string);
            }
            return objIndex;
        }
    }
 
    /*
     * Create a new object holding the string, add it to the object array,
     * and register its index in the object hashtable.
     */
 
    objPtr = Tcl_NewObj();
    if (allocStrRep) {
        if (inHeap) {           /* use input string for obj's string rep */
            objPtr->bytes = string;
        } else {
            if (length > 0) {
                objPtr->bytes = ckalloc((unsigned) length + 1);
                memcpy((VOID *) objPtr->bytes, (VOID *) string,
                        (size_t) length);
                objPtr->bytes[length] = '\0';
            }
        }
        objPtr->length = length;
    } else {                    /* leave the string rep NULL */
        if (inHeap) {
            ckfree(string);
        }
    }
 
    if (envPtr->objArrayNext >= envPtr->objArrayEnd) {
        ExpandObjectArray(envPtr);
    }
    objIndex = envPtr->objArrayNext;
    envPtr->objArrayPtr[objIndex] = objPtr;
    Tcl_IncrRefCount(objPtr);
    envPtr->objArrayNext++;
 
    if (hPtr) {
        Tcl_SetHashValue(hPtr, objIndex);
    }
    return objIndex;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclExpandCodeArray --
 *
 *      Procedure that uses malloc to allocate more storage for a
 *      CompileEnv's code array.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The byte code array in *envPtr is reallocated to a new array of
 *      double the size, and if envPtr->mallocedCodeArray is non-zero the
 *      old array is freed. Byte codes are copied from the old array to the
 *      new one.
 *
 *----------------------------------------------------------------------
 */
 
void
TclExpandCodeArray(envPtr)
    CompileEnv *envPtr;         /* Points to the CompileEnv whose code array
                                 * must be enlarged. */
{
    /*
     * envPtr->codeNext is equal to envPtr->codeEnd. The currently defined
     * code bytes are stored between envPtr->codeStart and
     * (envPtr->codeNext - 1) [inclusive].
     */
 
    size_t currBytes = TclCurrCodeOffset();
    size_t newBytes  = 2*(envPtr->codeEnd  - envPtr->codeStart);
    unsigned char *newPtr = (unsigned char *) ckalloc((unsigned) newBytes);
 
    /*
     * Copy from old code array to new, free old code array if needed, and
     * mark new code array as malloced.
     */
 
    memcpy((VOID *) newPtr, (VOID *) envPtr->codeStart, currBytes);
    if (envPtr->mallocedCodeArray) {
        ckfree((char *) envPtr->codeStart);
    }
    envPtr->codeStart = newPtr;
    envPtr->codeNext = (newPtr + currBytes);
    envPtr->codeEnd  = (newPtr + newBytes);
    envPtr->mallocedCodeArray = 1;
}
 
/*
 *----------------------------------------------------------------------
 *
 * ExpandObjectArray --
 *
 *      Procedure that uses malloc to allocate more storage for a
 *      CompileEnv's object array.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The object array in *envPtr is reallocated to a new array of
 *      double the size, and if envPtr->mallocedObjArray is non-zero the
 *      old array is freed. Tcl_Obj pointers are copied from the old array
 *      to the new one.
 *
 *----------------------------------------------------------------------
 */
 
static void
ExpandObjectArray(envPtr)
    CompileEnv *envPtr;         /* Points to the CompileEnv whose object
                                 * array must be enlarged. */
{
    /*
     * envPtr->objArrayNext is equal to envPtr->objArrayEnd. The currently
     * allocated Tcl_Obj pointers are stored between elements
     * 0 and (envPtr->objArrayNext - 1) [inclusive] in the object array
     * pointed to by objArrayPtr.
     */
 
    size_t currBytes = envPtr->objArrayNext * sizeof(Tcl_Obj *);
    int newElems = 2*envPtr->objArrayEnd;
    size_t newBytes = newElems * sizeof(Tcl_Obj *);
    Tcl_Obj **newPtr = (Tcl_Obj **) ckalloc((unsigned) newBytes);
 
    /*
     * Copy from old object array to new, free old object array if needed,
     * and mark new object array as malloced.
     */
 
    memcpy((VOID *) newPtr, (VOID *) envPtr->objArrayPtr, currBytes);
    if (envPtr->mallocedObjArray) {
        ckfree((char *) envPtr->objArrayPtr);
    }
    envPtr->objArrayPtr = (Tcl_Obj **) newPtr;
    envPtr->objArrayEnd = newElems;
    envPtr->mallocedObjArray = 1;
}
 
/*
 *----------------------------------------------------------------------
 *
 * EnterCmdStartData --
 *
 *      Registers the starting source and bytecode location of a
 *      command. This information is used at runtime to map between
 *      instruction pc and source locations.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Inserts source and code location information into the compilation
 *      environment envPtr for the command at index cmdIndex. The
 *      compilation environment's CmdLocation array is grown if necessary.
 *
 *----------------------------------------------------------------------
 */
 
static void
EnterCmdStartData(envPtr, cmdIndex, srcOffset, codeOffset)
    CompileEnv *envPtr;         /* Points to the compilation environment
                                 * structure in which to enter command
                                 * location information. */
    int cmdIndex;               /* Index of the command whose start data
                                 * is being set. */
    int srcOffset;              /* Offset of first char of the command. */
    int codeOffset;             /* Offset of first byte of command code. */
{
    CmdLocation *cmdLocPtr;
 
    if ((cmdIndex < 0) || (cmdIndex >= envPtr->numCommands)) {
        panic("EnterCmdStartData: bad command index %d\n", cmdIndex);
    }
 
    if (cmdIndex >= envPtr->cmdMapEnd) {
        /*
         * Expand the command location array by allocating more storage from
         * the heap. The currently allocated CmdLocation entries are stored
         * from cmdMapPtr[0] up to cmdMapPtr[envPtr->cmdMapEnd] (inclusive).
         */
 
        size_t currElems = envPtr->cmdMapEnd;
        size_t newElems  = 2*currElems;
        size_t currBytes = currElems * sizeof(CmdLocation);
        size_t newBytes  = newElems  * sizeof(CmdLocation);
        CmdLocation *newPtr = (CmdLocation *) ckalloc((unsigned) newBytes);
 
        /*
         * Copy from old command location array to new, free old command
         * location array if needed, and mark new array as malloced.
         */
 
        memcpy((VOID *) newPtr, (VOID *) envPtr->cmdMapPtr, currBytes);
        if (envPtr->mallocedCmdMap) {
            ckfree((char *) envPtr->cmdMapPtr);
        }
        envPtr->cmdMapPtr = (CmdLocation *) newPtr;
        envPtr->cmdMapEnd = newElems;
        envPtr->mallocedCmdMap = 1;
    }
 
    if (cmdIndex > 0) {
        if (codeOffset < envPtr->cmdMapPtr[cmdIndex-1].codeOffset) {
            panic("EnterCmdStartData: cmd map table not sorted by code offset");
        }
    }
 
    cmdLocPtr = &(envPtr->cmdMapPtr[cmdIndex]);
    cmdLocPtr->codeOffset = codeOffset;
    cmdLocPtr->srcOffset = srcOffset;
    cmdLocPtr->numSrcChars = -1;
    cmdLocPtr->numCodeBytes = -1;
}
 
/*
 *----------------------------------------------------------------------
 *
 * EnterCmdExtentData --
 *
 *      Registers the source and bytecode length for a command. This
 *      information is used at runtime to map between instruction pc and
 *      source locations.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Inserts source and code length information into the compilation
 *      environment envPtr for the command at index cmdIndex. Starting
 *      source and bytecode information for the command must already
 *      have been registered.
 *
 *----------------------------------------------------------------------
 */
 
static void
EnterCmdExtentData(envPtr, cmdIndex, numSrcChars, numCodeBytes)
    CompileEnv *envPtr;         /* Points to the compilation environment
                                 * structure in which to enter command
                                 * location information. */
    int cmdIndex;               /* Index of the command whose source and
                                 * code length data is being set. */
    int numSrcChars;            /* Number of command source chars. */
    int numCodeBytes;           /* Offset of last byte of command code. */
{
    CmdLocation *cmdLocPtr;
 
    if ((cmdIndex < 0) || (cmdIndex >= envPtr->numCommands)) {
        panic("EnterCmdStartData: bad command index %d\n", cmdIndex);
    }
 
    if (cmdIndex > envPtr->cmdMapEnd) {
        panic("EnterCmdStartData: no start data registered for command with index %d\n", cmdIndex);
    }
 
    cmdLocPtr = &(envPtr->cmdMapPtr[cmdIndex]);
    cmdLocPtr->numSrcChars = numSrcChars;
    cmdLocPtr->numCodeBytes = numCodeBytes;
}
 
/*
 *----------------------------------------------------------------------
 *
 * InitArgInfo --
 *
 *      Initializes a ArgInfo structure to hold information about
 *      some number of argument words in a command.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The ArgInfo structure is initialized.
 *
 *----------------------------------------------------------------------
 */
 
static void
InitArgInfo(argInfoPtr)
    register ArgInfo *argInfoPtr; /* Points to the ArgInfo structure
                                   * to initialize. */
{
    argInfoPtr->numArgs = 0;
    argInfoPtr->startArray = argInfoPtr->staticStartSpace;
    argInfoPtr->endArray   = argInfoPtr->staticEndSpace;
    argInfoPtr->allocArgs = ARGINFO_INIT_ENTRIES;
    argInfoPtr->mallocedArrays = 0;
}
 
/*
 *----------------------------------------------------------------------
 *
 * CollectArgInfo --
 *
 *      Procedure to scan the argument words of a command and record the
 *      start and finish of each argument word in a ArgInfo structure.
 *
 * Results:
 *      The return value is a standard Tcl result, which is TCL_OK unless
 *      there was an error while scanning string. If an error occurs then
 *      the interpreter's result contains a standard error message.
 *
 * Side effects:
 *      If necessary, the argument start and end arrays in *argInfoPtr
 *      are grown and reallocated to a new arrays of double the size, and
 *      if argInfoPtr->mallocedArray is non-zero the old arrays are freed.
 *
 *----------------------------------------------------------------------
 */
 
static int
CollectArgInfo(interp, string, lastChar, flags, argInfoPtr)
    Tcl_Interp *interp;         /* Used for error reporting. */
    char *string;               /* The source command string to scan. */
    char *lastChar;              /* Pointer to terminating character of
                                  * string. */
    int flags;                  /* Flags to control compilation (same as
                                 * passed to Tcl_Eval). */
    register ArgInfo *argInfoPtr;
                                /* Points to the ArgInfo structure in which
                                 * to record the arg word information. */
{
    register char *src = string;/* Points to current source char. */
    register int type;          /* Current char's CHAR_TYPE type. */
    int nestedCmd = (flags & TCL_BRACKET_TERM);
                                /* 1 if string being scanned is a nested
                                 * command and is terminated by a ']';
                                 * otherwise 0. */
    int scanningArgs;           /* 1 if still scanning argument words to
                                 * determine their start and end. */
    char *wordStart, *wordEnd;  /* Points to the first and last significant
                                 * characters of each word. */
    CompileEnv tempCompEnv;     /* Only used to hold the termOffset field
                                 * updated by AdvanceToNextWord. */
    char *prev;
 
    argInfoPtr->numArgs = 0;
    scanningArgs = 1;
    while (scanningArgs) {
        AdvanceToNextWord(src, &tempCompEnv);
        src += tempCompEnv.termOffset;
        type = CHAR_TYPE(src, lastChar);
 
        if ((type == TCL_COMMAND_END) && ((*src != ']') || nestedCmd)) {
            break;                  /* done collecting argument words */
        } else if (*src == '"') {
            wordStart = src;
            src = TclWordEnd(src, lastChar, nestedCmd, NULL);
            if (src == lastChar) {
                badStringTermination:
                Tcl_ResetResult(interp);
                Tcl_AppendToObj(Tcl_GetObjResult(interp),
                        "quoted string doesn't terminate properly", -1);
                return TCL_ERROR;
            }
            prev = (src-1);
            if (*src == '"') {
                wordEnd = src;
                src++;
            } else if ((*src == ';') && (*prev == '"')) {
                scanningArgs = 0;
                wordEnd = prev;
            } else {
                goto badStringTermination;
            }
        } else if (*src == '{') {
            wordStart = src;
            src = TclWordEnd(src, lastChar, nestedCmd, NULL);
            if (src == lastChar) {
                Tcl_ResetResult(interp);
                Tcl_AppendToObj(Tcl_GetObjResult(interp),
                        "missing close-brace", -1);
                return TCL_ERROR;
            }
            prev = (src-1);
            if (*src == '}') {
                wordEnd = src;
                src++;
            } else if ((*src == ';') && (*prev == '}')) {
                scanningArgs = 0;
                wordEnd = prev;
            } else {
                Tcl_ResetResult(interp);
                Tcl_AppendToObj(Tcl_GetObjResult(interp),
                        "argument word in braces doesn't terminate properly", -1);
                return TCL_ERROR;
            }
        } else {
            wordStart = src;
            src = TclWordEnd(src, lastChar, nestedCmd, NULL);
            prev = (src-1);
            if (src == lastChar) {
                Tcl_ResetResult(interp);
                Tcl_AppendToObj(Tcl_GetObjResult(interp),
                        "missing close-bracket or close-brace", -1);
                return TCL_ERROR;
            } else if (*src == ';') {
                scanningArgs = 0;
                wordEnd = prev;
            } else {
                wordEnd = src;
                src++;
                if ((src == lastChar) || (*src == '\n')
                        || ((*src == ']') && nestedCmd)) {
                    scanningArgs = 0;
                }
            }
        } /* end of test on each kind of word */
 
        if (argInfoPtr->numArgs == argInfoPtr->allocArgs) {
            int newArgs = 2*argInfoPtr->numArgs;
            size_t currBytes = argInfoPtr->numArgs * sizeof(char *);
            size_t newBytes  = newArgs * sizeof(char *);
            char **newStartArrayPtr =
                    (char **) ckalloc((unsigned) newBytes);
            char **newEndArrayPtr =
                    (char **) ckalloc((unsigned) newBytes);
 
            /*
             * Copy from the old arrays to the new, free the old arrays if
             * needed, and mark the new arrays as malloc'ed.
             */
 
            memcpy((VOID *) newStartArrayPtr,
                    (VOID *) argInfoPtr->startArray, currBytes);
            memcpy((VOID *) newEndArrayPtr,
                    (VOID *) argInfoPtr->endArray, currBytes);
            if (argInfoPtr->mallocedArrays) {
                ckfree((char *) argInfoPtr->startArray);
                ckfree((char *) argInfoPtr->endArray);
            }
            argInfoPtr->startArray = newStartArrayPtr;
            argInfoPtr->endArray   = newEndArrayPtr;
            argInfoPtr->allocArgs = newArgs;
            argInfoPtr->mallocedArrays = 1;
        }
        argInfoPtr->startArray[argInfoPtr->numArgs] = wordStart;
        argInfoPtr->endArray[argInfoPtr->numArgs]   = wordEnd;
        argInfoPtr->numArgs++;
    }
    return TCL_OK;
}
 
/*
 *----------------------------------------------------------------------
 *
 * FreeArgInfo --
 *
 *      Free any storage allocated in a ArgInfo structure.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Allocated storage in the ArgInfo structure is freed.
 *
 *----------------------------------------------------------------------
 */
 
static void
FreeArgInfo(argInfoPtr)
    register ArgInfo *argInfoPtr; /* Points to the ArgInfo structure
                                   * to free. */
{
    if (argInfoPtr->mallocedArrays) {
        ckfree((char *) argInfoPtr->startArray);
        ckfree((char *) argInfoPtr->endArray);
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * CreateExceptionRange --
 *
 *      Procedure that allocates and initializes a new ExceptionRange
 *      structure of the specified kind in a CompileEnv's ExceptionRange
 *      array.
 *
 * Results:
 *      Returns the index for the newly created ExceptionRange.
 *
 * Side effects:
 *      If there is not enough room in the CompileEnv's ExceptionRange
 *      array, the array in expanded: a new array of double the size is
 *      allocated, if envPtr->mallocedExcRangeArray is non-zero the old
 *      array is freed, and ExceptionRange entries are copied from the old
 *      array to the new one.
 *
 *----------------------------------------------------------------------
 */
 
static int
CreateExceptionRange(type, envPtr)
    ExceptionRangeType type;    /* The kind of ExceptionRange desired. */
    register CompileEnv *envPtr;/* Points to the CompileEnv for which a new
                                 * loop ExceptionRange structure is to be
                                 * allocated. */
{
    int index;                  /* Index for the newly-allocated
                                 * ExceptionRange structure. */
    register ExceptionRange *rangePtr;
                                /* Points to the new ExceptionRange
                                 * structure */
 
    index = envPtr->excRangeArrayNext;
    if (index >= envPtr->excRangeArrayEnd) {
        /*
         * Expand the ExceptionRange array. The currently allocated entries
         * are stored between elements 0 and (envPtr->excRangeArrayNext - 1)
         * [inclusive].
         */
 
        size_t currBytes =
                envPtr->excRangeArrayNext * sizeof(ExceptionRange);
        int newElems = 2*envPtr->excRangeArrayEnd;
        size_t newBytes = newElems * sizeof(ExceptionRange);
        ExceptionRange *newPtr = (ExceptionRange *)
                ckalloc((unsigned) newBytes);
 
        /*
         * Copy from old ExceptionRange array to new, free old
         * ExceptionRange array if needed, and mark the new ExceptionRange
         * array as malloced.
         */
 
        memcpy((VOID *) newPtr, (VOID *) envPtr->excRangeArrayPtr,
                currBytes);
        if (envPtr->mallocedExcRangeArray) {
            ckfree((char *) envPtr->excRangeArrayPtr);
        }
        envPtr->excRangeArrayPtr = (ExceptionRange *) newPtr;
        envPtr->excRangeArrayEnd = newElems;
        envPtr->mallocedExcRangeArray = 1;
    }
    envPtr->excRangeArrayNext++;
 
    rangePtr = &(envPtr->excRangeArrayPtr[index]);
    rangePtr->type = type;
    rangePtr->nestingLevel = envPtr->excRangeDepth;
    rangePtr->codeOffset = -1;
    rangePtr->numCodeBytes = -1;
    rangePtr->breakOffset = -1;
    rangePtr->continueOffset = -1;
    rangePtr->catchOffset = -1;
    return index;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclCreateAuxData --
 *
 *      Procedure that allocates and initializes a new AuxData structure in
 *      a CompileEnv's array of compilation auxiliary data records. These
 *      AuxData records hold information created during compilation by
 *      CompileProcs and used by instructions during execution.
 *
 * Results:
 *      Returns the index for the newly created AuxData structure.
 *
 * Side effects:
 *      If there is not enough room in the CompileEnv's AuxData array,
 *      the AuxData array in expanded: a new array of double the size
 *      is allocated, if envPtr->mallocedAuxDataArray is non-zero
 *      the old array is freed, and AuxData entries are copied from
 *      the old array to the new one.
 *
 *----------------------------------------------------------------------
 */
 
int
TclCreateAuxData(clientData, typePtr, envPtr)
    ClientData clientData;      /* The compilation auxiliary data to store
                             * in the new aux data record. */
    AuxDataType *typePtr;       /* Pointer to the type to attach to this AuxData */
    register CompileEnv *envPtr;/* Points to the CompileEnv for which a new
                                 * aux data structure is to be allocated. */
{
    int index;                  /* Index for the new AuxData structure. */
    register AuxData *auxDataPtr;
                                /* Points to the new AuxData structure */
 
    index = envPtr->auxDataArrayNext;
    if (index >= envPtr->auxDataArrayEnd) {
        /*
         * Expand the AuxData array. The currently allocated entries are
         * stored between elements 0 and (envPtr->auxDataArrayNext - 1)
         * [inclusive].
         */
 
        size_t currBytes = envPtr->auxDataArrayNext * sizeof(AuxData);
        int newElems = 2*envPtr->auxDataArrayEnd;
        size_t newBytes = newElems * sizeof(AuxData);
        AuxData *newPtr = (AuxData *) ckalloc((unsigned) newBytes);
 
        /*
         * Copy from old AuxData array to new, free old AuxData array if
         * needed, and mark the new AuxData array as malloced.
         */
 
        memcpy((VOID *) newPtr, (VOID *) envPtr->auxDataArrayPtr,
                currBytes);
        if (envPtr->mallocedAuxDataArray) {
            ckfree((char *) envPtr->auxDataArrayPtr);
        }
        envPtr->auxDataArrayPtr = newPtr;
        envPtr->auxDataArrayEnd = newElems;
        envPtr->mallocedAuxDataArray = 1;
    }
    envPtr->auxDataArrayNext++;
 
    auxDataPtr = &(envPtr->auxDataArrayPtr[index]);
    auxDataPtr->type = typePtr;
    auxDataPtr->clientData = clientData;
    return index;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclInitJumpFixupArray --
 *
 *      Initializes a JumpFixupArray structure to hold some number of
 *      jump fixup entries.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The JumpFixupArray structure is initialized.
 *
 *----------------------------------------------------------------------
 */
 
void
TclInitJumpFixupArray(fixupArrayPtr)
    register JumpFixupArray *fixupArrayPtr;
                                 /* Points to the JumpFixupArray structure
                                  * to initialize. */
{
    fixupArrayPtr->fixup = fixupArrayPtr->staticFixupSpace;
    fixupArrayPtr->next = 0;
    fixupArrayPtr->end = (JUMPFIXUP_INIT_ENTRIES - 1);
    fixupArrayPtr->mallocedArray = 0;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclExpandJumpFixupArray --
 *
 *      Procedure that uses malloc to allocate more storage for a
 *      jump fixup array.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The jump fixup array in *fixupArrayPtr is reallocated to a new array
 *      of double the size, and if fixupArrayPtr->mallocedArray is non-zero
 *      the old array is freed. Jump fixup structures are copied from the
 *      old array to the new one.
 *
 *----------------------------------------------------------------------
 */
 
void
TclExpandJumpFixupArray(fixupArrayPtr)
    register JumpFixupArray *fixupArrayPtr;
                                 /* Points to the JumpFixupArray structure
                                  * to enlarge. */
{
    /*
     * The currently allocated jump fixup entries are stored from fixup[0]
     * up to fixup[fixupArrayPtr->fixupNext] (*not* inclusive). We assume
     * fixupArrayPtr->fixupNext is equal to fixupArrayPtr->fixupEnd.
     */
 
    size_t currBytes = fixupArrayPtr->next * sizeof(JumpFixup);
    int newElems = 2*(fixupArrayPtr->end + 1);
    size_t newBytes = newElems * sizeof(JumpFixup);
    JumpFixup *newPtr = (JumpFixup *) ckalloc((unsigned) newBytes);
 
    /*
     * Copy from the old array to new, free the old array if needed,
     * and mark the new array as malloced.
     */
 
    memcpy((VOID *) newPtr, (VOID *) fixupArrayPtr->fixup, currBytes);
    if (fixupArrayPtr->mallocedArray) {
        ckfree((char *) fixupArrayPtr->fixup);
    }
    fixupArrayPtr->fixup = (JumpFixup *) newPtr;
    fixupArrayPtr->end = newElems;
    fixupArrayPtr->mallocedArray = 1;
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclFreeJumpFixupArray --
 *
 *      Free any storage allocated in a jump fixup array structure.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Allocated storage in the JumpFixupArray structure is freed.
 *
 *----------------------------------------------------------------------
 */
 
void
TclFreeJumpFixupArray(fixupArrayPtr)
    register JumpFixupArray *fixupArrayPtr;
                                 /* Points to the JumpFixupArray structure
                                  * to free. */
{
    if (fixupArrayPtr->mallocedArray) {
        ckfree((char *) fixupArrayPtr->fixup);
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclEmitForwardJump --
 *
 *      Procedure to emit a two-byte forward jump of kind "jumpType". Since
 *      the jump may later have to be grown to five bytes if the jump target
 *      is more than, say, 127 bytes away, this procedure also initializes a
 *      JumpFixup record with information about the jump.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The JumpFixup record pointed to by "jumpFixupPtr" is initialized
 *      with information needed later if the jump is to be grown. Also,
 *      a two byte jump of the designated type is emitted at the current
 *      point in the bytecode stream.
 *
 *----------------------------------------------------------------------
 */
 
void
TclEmitForwardJump(envPtr, jumpType, jumpFixupPtr)
    CompileEnv *envPtr;         /* Points to the CompileEnv structure that
                                 * holds the resulting instruction. */
    TclJumpType jumpType;       /* Indicates the kind of jump: if true or
                                 * false or unconditional. */
    JumpFixup *jumpFixupPtr;    /* Points to the JumpFixup structure to
                                 * initialize with information about this
                                 * forward jump. */
{
    /*
     * Initialize the JumpFixup structure:
     *    - codeOffset is offset of first byte of jump below
     *    - cmdIndex is index of the command after the current one
     *    - excRangeIndex is the index of the first ExceptionRange after
     *      the current one.
     */
 
    jumpFixupPtr->jumpType = jumpType;
    jumpFixupPtr->codeOffset = TclCurrCodeOffset();
    jumpFixupPtr->cmdIndex = envPtr->numCommands;
    jumpFixupPtr->excRangeIndex = envPtr->excRangeArrayNext;
 
    switch (jumpType) {
    case TCL_UNCONDITIONAL_JUMP:
        TclEmitInstInt1(INST_JUMP1, /*offset*/ 0, envPtr);
        break;
    case TCL_TRUE_JUMP:
        TclEmitInstInt1(INST_JUMP_TRUE1, /*offset*/ 0, envPtr);
        break;
    default:
        TclEmitInstInt1(INST_JUMP_FALSE1, /*offset*/ 0, envPtr);
        break;
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclFixupForwardJump --
 *
 *      Procedure that updates a previously-emitted forward jump to jump
 *      a specified number of bytes, "jumpDist". If necessary, the jump is
 *      grown from two to five bytes; this is done if the jump distance is
 *      greater than "distThreshold" (normally 127 bytes). The jump is
 *      described by a JumpFixup record previously initialized by
 *      TclEmitForwardJump.
 *
 * Results:
 *      1 if the jump was grown and subsequent instructions had to be moved;
 *      otherwise 0. This result is returned to allow callers to update
 *      any additional code offsets they may hold.
 *
 * Side effects:
 *      The jump may be grown and subsequent instructions moved. If this
 *      happens, the code offsets for any commands and any ExceptionRange
 *      records between the jump and the current code address will be
 *      updated to reflect the moved code. Also, the bytecode instruction
 *      array in the CompileEnv structure may be grown and reallocated.
 *
 *----------------------------------------------------------------------
 */
 
int
TclFixupForwardJump(envPtr, jumpFixupPtr, jumpDist, distThreshold)
    CompileEnv *envPtr;         /* Points to the CompileEnv structure that
                                 * holds the resulting instruction. */
    JumpFixup *jumpFixupPtr;    /* Points to the JumpFixup structure that
                                 * describes the forward jump. */
    int jumpDist;               /* Jump distance to set in jump
                                 * instruction. */
    int distThreshold;          /* Maximum distance before the two byte
                                 * jump is grown to five bytes. */
{
    unsigned char *jumpPc, *p;
    int firstCmd, lastCmd, firstRange, lastRange, k;
    unsigned int numBytes;
 
    if (jumpDist <= distThreshold) {
        jumpPc = (envPtr->codeStart + jumpFixupPtr->codeOffset);
        switch (jumpFixupPtr->jumpType) {
        case TCL_UNCONDITIONAL_JUMP:
            TclUpdateInstInt1AtPc(INST_JUMP1, jumpDist, jumpPc);
            break;
        case TCL_TRUE_JUMP:
            TclUpdateInstInt1AtPc(INST_JUMP_TRUE1, jumpDist, jumpPc);
            break;
        default:
            TclUpdateInstInt1AtPc(INST_JUMP_FALSE1, jumpDist, jumpPc);
            break;
        }
        return 0;
    }
 
    /*
     * We must grow the jump then move subsequent instructions down.
     */
 
    TclEnsureCodeSpace(3, envPtr);  /* NB: might change code addresses! */
    jumpPc = (envPtr->codeStart + jumpFixupPtr->codeOffset);
    for (numBytes = envPtr->codeNext-jumpPc-2, p = jumpPc+2+numBytes-1;
            numBytes > 0;  numBytes--, p--) {
        p[3] = p[0];
    }
    envPtr->codeNext += 3;
    jumpDist += 3;
    switch (jumpFixupPtr->jumpType) {
    case TCL_UNCONDITIONAL_JUMP:
        TclUpdateInstInt4AtPc(INST_JUMP4, jumpDist, jumpPc);
        break;
    case TCL_TRUE_JUMP:
        TclUpdateInstInt4AtPc(INST_JUMP_TRUE4, jumpDist, jumpPc);
        break;
    default:
        TclUpdateInstInt4AtPc(INST_JUMP_FALSE4, jumpDist, jumpPc);
        break;
    }
 
    /*
     * Adjust the code offsets for any commands and any ExceptionRange
     * records between the jump and the current code address.
     */
 
    firstCmd = jumpFixupPtr->cmdIndex;
    lastCmd  = (envPtr->numCommands - 1);
    if (firstCmd < lastCmd) {
        for (k = firstCmd;  k <= lastCmd;  k++) {
            (envPtr->cmdMapPtr[k]).codeOffset += 3;
        }
    }
 
    firstRange = jumpFixupPtr->excRangeIndex;
    lastRange  = (envPtr->excRangeArrayNext - 1);
    for (k = firstRange;  k <= lastRange;  k++) {
        ExceptionRange *rangePtr = &(envPtr->excRangeArrayPtr[k]);
        rangePtr->codeOffset += 3;
 
        switch (rangePtr->type) {
        case LOOP_EXCEPTION_RANGE:
            rangePtr->breakOffset += 3;
            if (rangePtr->continueOffset != -1) {
                rangePtr->continueOffset += 3;
            }
            break;
        case CATCH_EXCEPTION_RANGE:
            rangePtr->catchOffset += 3;
            break;
        default:
            panic("TclFixupForwardJump: unrecognized ExceptionRange type %d\n", rangePtr->type);
        }
    }
    return 1;                   /* the jump was grown */
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclGetInstructionTable --
 *
 *  Returns a pointer to the table describing Tcl bytecode instructions.
 *  This procedure is defined so that clients can access the pointer from
 *  outside the TCL DLLs.
 *
 * Results:
 *      Returns a pointer to the global instruction table, same as the expression
 *  (&instructionTable[0]).
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
 
InstructionDesc *
TclGetInstructionTable()
{
    return &instructionTable[0];
}
 
/*
 *--------------------------------------------------------------
 *
 * TclRegisterAuxDataType --
 *
 *      This procedure is called to register a new AuxData type
 *      in the table of all AuxData types supported by Tcl.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The type is registered in the AuxData type table. If there was already
 *      a type with the same name as in typePtr, it is replaced with the
 *      new type.
 *
 *--------------------------------------------------------------
 */
 
void
TclRegisterAuxDataType(typePtr)
    AuxDataType *typePtr;       /* Information about object type;
                             * storage must be statically
                             * allocated (must live forever). */
{
    register Tcl_HashEntry *hPtr;
    int new;
 
    if (!auxDataTypeTableInitialized) {
        TclInitAuxDataTypeTable();
    }
 
    /*
     * If there's already a type with the given name, remove it.
     */
 
    hPtr = Tcl_FindHashEntry(&auxDataTypeTable, typePtr->name);
    if (hPtr != (Tcl_HashEntry *) NULL) {
        Tcl_DeleteHashEntry(hPtr);
    }
 
    /*
     * Now insert the new object type.
     */
 
    hPtr = Tcl_CreateHashEntry(&auxDataTypeTable, typePtr->name, &new);
    if (new) {
        Tcl_SetHashValue(hPtr, typePtr);
    }
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclGetAuxDataType --
 *
 *      This procedure looks up an Auxdata type by name.
 *
 * Results:
 *      If an AuxData type with name matching "typeName" is found, a pointer
 *      to its AuxDataType structure is returned; otherwise, NULL is returned.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
 
AuxDataType *
TclGetAuxDataType(typeName)
    char *typeName;             /* Name of AuxData type to look up. */
{
    register Tcl_HashEntry *hPtr;
    AuxDataType *typePtr = NULL;
 
    if (!auxDataTypeTableInitialized) {
        TclInitAuxDataTypeTable();
    }
 
    hPtr = Tcl_FindHashEntry(&auxDataTypeTable, typeName);
    if (hPtr != (Tcl_HashEntry *) NULL) {
        typePtr = (AuxDataType *) Tcl_GetHashValue(hPtr);
    }
 
    return typePtr;
}
 
/*
 *--------------------------------------------------------------
 *
 * TclInitAuxDataTypeTable --
 *
 *      This procedure is invoked to perform once-only initialization of
 *      the AuxData type table. It also registers the AuxData types defined in
 *      this file.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Initializes the table of defined AuxData types "auxDataTypeTable" with
 *      builtin AuxData types defined in this file.
 *
 *--------------------------------------------------------------
 */
 
void
TclInitAuxDataTypeTable()
{
    auxDataTypeTableInitialized = 1;
 
    Tcl_InitHashTable(&auxDataTypeTable, TCL_STRING_KEYS);
    TclRegisterAuxDataType(&tclForeachInfoType);
}
 
/*
 *----------------------------------------------------------------------
 *
 * TclFinalizeAuxDataTypeTable --
 *
 *      This procedure is called by Tcl_Finalize after all exit handlers
 *      have been run to free up storage associated with the table of AuxData
 *      types.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Deletes all entries in the hash table of AuxData types, "auxDataTypeTable".
 *
 *----------------------------------------------------------------------
 */
 
void
TclFinalizeAuxDataTypeTable()
{
    if (auxDataTypeTableInitialized) {
        Tcl_DeleteHashTable(&auxDataTypeTable);
        auxDataTypeTableInitialized = 0;
    }
}
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[/] [or1k/] [trunk/] [insight/] [tcl/] [generic/] [tclCompile.c] - Blame information for rev 1765

Line No.	Rev	Author	Line
1	578	markom	`/*`
2			`* tclCompile.c --`
3			`*`
4			`* This file contains procedures that compile Tcl commands or parts`
5			`* of commands (like quoted strings or nested sub-commands) into a`
6			`* sequence of instructions ("bytecodes").`
7			`*`
8			`* Copyright (c) 1996-1997 Sun Microsystems, Inc.`
9			`*`
10			`* See the file "license.terms" for information on usage and redistribution`
11			`* of this file, and for a DISCLAIMER OF ALL WARRANTIES.`
12			`*`
13			`* RCS: @(#) $Id: tclCompile.c,v 1.1.1.1 2002-01-16 10:25:26 markom Exp $`
14			`*/`
15
16			`#include "tclInt.h"`
17			`#include "tclCompile.h"`
18
19			`/*`
20			`* Variable that controls whether compilation tracing is enabled and, if so,`
21			`* what level of tracing is desired:`
22			`* 0: no compilation tracing`
23			`* 1: summarize compilation of top level cmds and proc bodies`
24			`* 2: display all instructions of each ByteCode compiled`
25			`* This variable is linked to the Tcl variable "tcl_traceCompile".`
26			`*/`
27
28			`int tclTraceCompile = 0;`
29			`static int traceInitialized = 0;`
30
31			`/*`
32			`* Count of the number of compilations and various other compilation-`
33			`* related statistics.`
34			`*/`
35
36			`#ifdef TCL_COMPILE_STATS`
37			`long tclNumCompilations = 0;`
38			`double tclTotalSourceBytes = 0.0;`
39			`double tclTotalCodeBytes = 0.0;`
40