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/* Print in infix form a struct expression.

   Copyright (C) 1986, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,

   1998, 1999, 2000, 2003, 2007, 2008 Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"

#include "symtab.h"

#include "gdbtypes.h"

#include "expression.h"

#include "value.h"

#include "language.h"

#include "parser-defs.h"

#include "user-regs.h"          /* For user_reg_map_regnum_to_name.  */

#include "target.h"

#include "gdb_string.h"

#include "block.h"

#include "objfiles.h"

#include "gdb_assert.h"

#ifdef HAVE_CTYPE_H

#include <ctype.h>

#endif

void

print_expression (struct expression *exp, struct ui_file *stream)

{

  int pc = 0;

  print_subexp (exp, &pc, stream, PREC_NULL);

}

/* Print the subexpression of EXP that starts in position POS, on STREAM.

   PREC is the precedence of the surrounding operator;

   if the precedence of the main operator of this subexpression is less,

   parentheses are needed here.  */

void

print_subexp (struct expression *exp, int *pos,

              struct ui_file *stream, enum precedence prec)

{

  exp->language_defn->la_exp_desc->print_subexp (exp, pos, stream, prec);

}

/* Standard implementation of print_subexp for use in language_defn

   vectors.  */

void

print_subexp_standard (struct expression *exp, int *pos,

                       struct ui_file *stream, enum precedence prec)

{

  unsigned tem;

  const struct op_print *op_print_tab;

  int pc;

  unsigned nargs;

  char *op_str;

  int assign_modify = 0;

  enum exp_opcode opcode;

  enum precedence myprec = PREC_NULL;

  /* Set to 1 for a right-associative operator.  */

  int assoc = 0;

  struct value *val;

  char *tempstr = NULL;

  op_print_tab = exp->language_defn->la_op_print_tab;

  pc = (*pos)++;

  opcode = exp->elts[pc].opcode;

  switch (opcode)

    {

      /* Common ops */

    case OP_SCOPE:

      myprec = PREC_PREFIX;

      assoc = 0;

      fputs_filtered (type_name_no_tag (exp->elts[pc + 1].type), stream);

      fputs_filtered ("::", stream);

      nargs = longest_to_int (exp->elts[pc + 2].longconst);

      (*pos) += 4 + BYTES_TO_EXP_ELEM (nargs + 1);

      fputs_filtered (&exp->elts[pc + 3].string, stream);

      return;

    case OP_LONG:

      (*pos) += 3;

      value_print (value_from_longest (exp->elts[pc + 1].type,

                                       exp->elts[pc + 2].longconst),

                   stream, 0, Val_no_prettyprint);

      return;

    case OP_DOUBLE:

      (*pos) += 3;

      value_print (value_from_double (exp->elts[pc + 1].type,

                                      exp->elts[pc + 2].doubleconst),

                   stream, 0, Val_no_prettyprint);

      return;

    case OP_VAR_VALUE:

      {

        struct block *b;

        (*pos) += 3;

        b = exp->elts[pc + 1].block;

        if (b != NULL

            && BLOCK_FUNCTION (b) != NULL

            && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)) != NULL)

          {

            fputs_filtered (SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)), stream);

            fputs_filtered ("::", stream);

          }

        fputs_filtered (SYMBOL_PRINT_NAME (exp->elts[pc + 2].symbol), stream);

      }

      return;

    case OP_LAST:

      (*pos) += 2;

      fprintf_filtered (stream, "$%d",

                        longest_to_int (exp->elts[pc + 1].longconst));

      return;

    case OP_REGISTER:

      {

        const char *name = &exp->elts[pc + 2].string;

        (*pos) += 3 + BYTES_TO_EXP_ELEM (exp->elts[pc + 1].longconst + 1);

        fprintf_filtered (stream, "$%s", name);

        return;

      }

    case OP_BOOL:

      (*pos) += 2;

      fprintf_filtered (stream, "%s",

                        longest_to_int (exp->elts[pc + 1].longconst)

                        ? "TRUE" : "FALSE");

      return;

    case OP_INTERNALVAR:

      (*pos) += 2;

      fprintf_filtered (stream, "$%s",

                        internalvar_name (exp->elts[pc + 1].internalvar));

      return;

    case OP_FUNCALL:

      (*pos) += 2;

      nargs = longest_to_int (exp->elts[pc + 1].longconst);

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      fputs_filtered (" (", stream);

      for (tem = 0; tem < nargs; tem++)

        {

          if (tem != 0)

            fputs_filtered (", ", stream);

          print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);

        }

      fputs_filtered (")", stream);

      return;

    case OP_NAME:

      nargs = longest_to_int (exp->elts[pc + 1].longconst);

      (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);

      fputs_filtered (&exp->elts[pc + 2].string, stream);

      return;

    case OP_STRING:

      nargs = longest_to_int (exp->elts[pc + 1].longconst);

      (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);

      /* LA_PRINT_STRING will print using the current repeat count threshold.

         If necessary, we can temporarily set it to zero, or pass it as an

         additional parameter to LA_PRINT_STRING.  -fnf */

      LA_PRINT_STRING (stream, &exp->elts[pc + 2].string, nargs, 1, 0);

      return;

    case OP_BITSTRING:

      nargs = longest_to_int (exp->elts[pc + 1].longconst);

      (*pos)

        += 3 + BYTES_TO_EXP_ELEM ((nargs + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT);

      fprintf_unfiltered (stream, "B'<unimplemented>'");

      return;

    case OP_OBJC_NSSTRING:      /* Objective-C Foundation Class NSString constant.  */

      nargs = longest_to_int (exp->elts[pc + 1].longconst);

      (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);

      fputs_filtered ("@\"", stream);

      LA_PRINT_STRING (stream, &exp->elts[pc + 2].string, nargs, 1, 0);

      fputs_filtered ("\"", stream);

      return;

    case OP_OBJC_MSGCALL:

      {                 /* Objective C message (method) call.  */

        char *selector;

        (*pos) += 3;

        nargs = longest_to_int (exp->elts[pc + 2].longconst);

        fprintf_unfiltered (stream, "[");

        print_subexp (exp, pos, stream, PREC_SUFFIX);

        if (0 == target_read_string (exp->elts[pc + 1].longconst,

                                     &selector, 1024, NULL))

          {

            error (_("bad selector"));

            return;

          }

        if (nargs)

          {

            char *s, *nextS;

            s = alloca (strlen (selector) + 1);

            strcpy (s, selector);

            for (tem = 0; tem < nargs; tem++)

              {

                nextS = strchr (s, ':');

                gdb_assert (nextS);     /* Make sure we found ':'.  */

                *nextS = '\0';

                fprintf_unfiltered (stream, " %s: ", s);

                s = nextS + 1;

                print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);

              }

          }

        else

          {

            fprintf_unfiltered (stream, " %s", selector);

          }

        fprintf_unfiltered (stream, "]");

        /* "selector" was malloc'd by target_read_string. Free it.  */

        xfree (selector);

        return;

      }

    case OP_ARRAY:

      (*pos) += 3;

      nargs = longest_to_int (exp->elts[pc + 2].longconst);

      nargs -= longest_to_int (exp->elts[pc + 1].longconst);

      nargs++;

      tem = 0;

      if (exp->elts[pc + 4].opcode == OP_LONG

          && exp->elts[pc + 5].type == builtin_type_char

          && exp->language_defn->la_language == language_c)

        {

          /* Attempt to print C character arrays using string syntax.

             Walk through the args, picking up one character from each

             of the OP_LONG expression elements.  If any array element

             does not match our expection of what we should find for

             a simple string, revert back to array printing.  Note that

             the last expression element is an explicit null terminator

             byte, which doesn't get printed. */

          tempstr = alloca (nargs);

          pc += 4;

          while (tem < nargs)

            {

              if (exp->elts[pc].opcode != OP_LONG

                  || exp->elts[pc + 1].type != builtin_type_char)

                {

                  /* Not a simple array of char, use regular array printing. */

                  tem = 0;

                  break;

                }

              else

                {

                  tempstr[tem++] =

                    longest_to_int (exp->elts[pc + 2].longconst);

                  pc += 4;

                }

            }

        }

      if (tem > 0)

        {

          LA_PRINT_STRING (stream, tempstr, nargs - 1, 1, 0);

          (*pos) = pc;

        }

      else

        {

          fputs_filtered (" {", stream);

          for (tem = 0; tem < nargs; tem++)

            {

              if (tem != 0)

                {

                  fputs_filtered (", ", stream);

                }

              print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);

            }

          fputs_filtered ("}", stream);

        }

      return;

    case OP_LABELED:

      tem = longest_to_int (exp->elts[pc + 1].longconst);

      (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);

      /* Gcc support both these syntaxes.  Unsure which is preferred.  */

#if 1

      fputs_filtered (&exp->elts[pc + 2].string, stream);

      fputs_filtered (": ", stream);

#else

      fputs_filtered (".", stream);

      fputs_filtered (&exp->elts[pc + 2].string, stream);

      fputs_filtered ("=", stream);

#endif

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      return;

    case TERNOP_COND:

      if ((int) prec > (int) PREC_COMMA)

        fputs_filtered ("(", stream);

      /* Print the subexpressions, forcing parentheses

         around any binary operations within them.

         This is more parentheses than are strictly necessary,

         but it looks clearer.  */

      print_subexp (exp, pos, stream, PREC_HYPER);

      fputs_filtered (" ? ", stream);

      print_subexp (exp, pos, stream, PREC_HYPER);

      fputs_filtered (" : ", stream);

      print_subexp (exp, pos, stream, PREC_HYPER);

      if ((int) prec > (int) PREC_COMMA)

        fputs_filtered (")", stream);

      return;

    case TERNOP_SLICE:

    case TERNOP_SLICE_COUNT:

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      fputs_filtered ("(", stream);

      print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);

      fputs_filtered (opcode == TERNOP_SLICE ? " : " : " UP ", stream);

      print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);

      fputs_filtered (")", stream);

      return;

    case STRUCTOP_STRUCT:

      tem = longest_to_int (exp->elts[pc + 1].longconst);

      (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      fputs_filtered (".", stream);

      fputs_filtered (&exp->elts[pc + 2].string, stream);

      return;

      /* Will not occur for Modula-2 */

    case STRUCTOP_PTR:

      tem = longest_to_int (exp->elts[pc + 1].longconst);

      (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      fputs_filtered ("->", stream);

      fputs_filtered (&exp->elts[pc + 2].string, stream);

      return;

    case STRUCTOP_MEMBER:

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      fputs_filtered (".*", stream);

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      return;

    case STRUCTOP_MPTR:

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      fputs_filtered ("->*", stream);

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      return;

    case BINOP_SUBSCRIPT:

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      fputs_filtered ("[", stream);

      print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);

      fputs_filtered ("]", stream);

      return;

    case UNOP_POSTINCREMENT:

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      fputs_filtered ("++", stream);

      return;

    case UNOP_POSTDECREMENT:

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      fputs_filtered ("--", stream);

      return;

    case UNOP_CAST:

      (*pos) += 2;

      if ((int) prec > (int) PREC_PREFIX)

        fputs_filtered ("(", stream);

      fputs_filtered ("(", stream);

      type_print (exp->elts[pc + 1].type, "", stream, 0);

      fputs_filtered (") ", stream);

      print_subexp (exp, pos, stream, PREC_PREFIX);

      if ((int) prec > (int) PREC_PREFIX)

        fputs_filtered (")", stream);

      return;

    case UNOP_MEMVAL:

      (*pos) += 2;

      if ((int) prec > (int) PREC_PREFIX)

        fputs_filtered ("(", stream);

      if (TYPE_CODE (exp->elts[pc + 1].type) == TYPE_CODE_FUNC &&

          exp->elts[pc + 3].opcode == OP_LONG)

        {

          /* We have a minimal symbol fn, probably.  It's encoded

             as a UNOP_MEMVAL (function-type) of an OP_LONG (int, address).

             Swallow the OP_LONG (including both its opcodes); ignore

             its type; print the value in the type of the MEMVAL.  */

          (*pos) += 4;

          val = value_at_lazy (exp->elts[pc + 1].type,

                               (CORE_ADDR) exp->elts[pc + 5].longconst);

          value_print (val, stream, 0, Val_no_prettyprint);

        }

      else

        {

          fputs_filtered ("{", stream);

          type_print (exp->elts[pc + 1].type, "", stream, 0);

          fputs_filtered ("} ", stream);

          print_subexp (exp, pos, stream, PREC_PREFIX);

        }

      if ((int) prec > (int) PREC_PREFIX)

        fputs_filtered (")", stream);

      return;

    case UNOP_MEMVAL_TLS:

      (*pos) += 3;

      if ((int) prec > (int) PREC_PREFIX)

        fputs_filtered ("(", stream);

      fputs_filtered ("{", stream);

      type_print (exp->elts[pc + 2].type, "", stream, 0);

      fputs_filtered ("} ", stream);

      print_subexp (exp, pos, stream, PREC_PREFIX);

      if ((int) prec > (int) PREC_PREFIX)

        fputs_filtered (")", stream);

      return;

    case BINOP_ASSIGN_MODIFY:

      opcode = exp->elts[pc + 1].opcode;

      (*pos) += 2;

      myprec = PREC_ASSIGN;

      assoc = 1;

      assign_modify = 1;

      op_str = "???";

      for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)

        if (op_print_tab[tem].opcode == opcode)

          {

            op_str = op_print_tab[tem].string;

            break;

          }

      if (op_print_tab[tem].opcode != opcode)

        /* Not found; don't try to keep going because we don't know how

           to interpret further elements.  */

        error (_("Invalid expression"));

      break;

      /* C++ ops */

    case OP_THIS:

      ++(*pos);

      fputs_filtered ("this", stream);

      return;

      /* Objective-C ops */

    case OP_OBJC_SELF:

      ++(*pos);

      fputs_filtered ("self", stream);  /* The ObjC equivalent of "this".  */

      return;

      /* Modula-2 ops */

    case MULTI_SUBSCRIPT:

      (*pos) += 2;

      nargs = longest_to_int (exp->elts[pc + 1].longconst);

      print_subexp (exp, pos, stream, PREC_SUFFIX);

      fprintf_unfiltered (stream, " [");

      for (tem = 0; tem < nargs; tem++)

        {

          if (tem != 0)

            fprintf_unfiltered (stream, ", ");

          print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);

        }

      fprintf_unfiltered (stream, "]");

      return;

    case BINOP_VAL:

      (*pos) += 2;

      fprintf_unfiltered (stream, "VAL(");

      type_print (exp->elts[pc + 1].type, "", stream, 0);

      fprintf_unfiltered (stream, ",");

      print_subexp (exp, pos, stream, PREC_PREFIX);

      fprintf_unfiltered (stream, ")");

      return;

    case BINOP_INCL:

    case BINOP_EXCL:

      error (_("print_subexp:  Not implemented."));

      /* Default ops */

    default:

      op_str = "???";

      for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)

        if (op_print_tab[tem].opcode == opcode)

          {

            op_str = op_print_tab[tem].string;

            myprec = op_print_tab[tem].precedence;

            assoc = op_print_tab[tem].right_assoc;

            break;

          }

      if (op_print_tab[tem].opcode != opcode)

        /* Not found; don't try to keep going because we don't know how

           to interpret further elements.  For example, this happens

           if opcode is OP_TYPE.  */

        error (_("Invalid expression"));

    }

  /* Note that PREC_BUILTIN will always emit parentheses. */

  if ((int) myprec < (int) prec)

    fputs_filtered ("(", stream);

  if ((int) opcode > (int) BINOP_END)

    {

      if (assoc)

        {

          /* Unary postfix operator.  */

          print_subexp (exp, pos, stream, PREC_SUFFIX);

          fputs_filtered (op_str, stream);

        }

      else

        {

          /* Unary prefix operator.  */

          fputs_filtered (op_str, stream);

          if (myprec == PREC_BUILTIN_FUNCTION)

            fputs_filtered ("(", stream);

          print_subexp (exp, pos, stream, PREC_PREFIX);

          if (myprec == PREC_BUILTIN_FUNCTION)

            fputs_filtered (")", stream);

        }

    }

  else

    {

      /* Binary operator.  */

      /* Print left operand.

         If operator is right-associative,

         increment precedence for this operand.  */

      print_subexp (exp, pos, stream,

                    (enum precedence) ((int) myprec + assoc));

      /* Print the operator itself.  */

      if (assign_modify)

        fprintf_filtered (stream, " %s= ", op_str);

      else if (op_str[0] == ',')

        fprintf_filtered (stream, "%s ", op_str);

      else

        fprintf_filtered (stream, " %s ", op_str);

      /* Print right operand.

         If operator is left-associative,

         increment precedence for this operand.  */

      print_subexp (exp, pos, stream,

                    (enum precedence) ((int) myprec + !assoc));

    }

  if ((int) myprec < (int) prec)

    fputs_filtered (")", stream);

}

/* Return the operator corresponding to opcode OP as

   a string.   NULL indicates that the opcode was not found in the

   current language table.  */

char *

op_string (enum exp_opcode op)

{

  int tem;

  const struct op_print *op_print_tab;

  op_print_tab = current_language->la_op_print_tab;

  for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)

    if (op_print_tab[tem].opcode == op)

      return op_print_tab[tem].string;

  return NULL;

}

/* Support for dumping the raw data from expressions in a human readable

   form.  */

static char *op_name (struct expression *, enum exp_opcode);

static int dump_subexp_body (struct expression *exp, struct ui_file *, int);

/* Name for OPCODE, when it appears in expression EXP. */

static char *

op_name (struct expression *exp, enum exp_opcode opcode)

{

  return exp->language_defn->la_exp_desc->op_name (opcode);

}

/* Default name for the standard operator OPCODE (i.e., one defined in

   the definition of enum exp_opcode).  */

char *

op_name_standard (enum exp_opcode opcode)

{

  switch (opcode)

    {

    default:

      {

        static char buf[30];

        sprintf (buf, "<unknown %d>", opcode);

        return buf;

      }

    case OP_NULL:

      return "OP_NULL";

    case BINOP_ADD:

      return "BINOP_ADD";

    case BINOP_SUB:

      return "BINOP_SUB";

    case BINOP_MUL:

      return "BINOP_MUL";

    case BINOP_DIV:

      return "BINOP_DIV";

    case BINOP_REM:

      return "BINOP_REM";

    case BINOP_MOD:

      return "BINOP_MOD";

    case BINOP_LSH:

      return "BINOP_LSH";

    case BINOP_RSH:

      return "BINOP_RSH";

    case BINOP_LOGICAL_AND:

      return "BINOP_LOGICAL_AND";