Subversion Repositories openrisc_2011-10-31

/* TREELANG Compiler interface to GCC's middle end (treetree.c)

   Called by the parser.

   If you want a working example of how to write a front end to GCC,

   you are in the right place.

   Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,

   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007

   Free Software Foundation, Inc.

   This code is based on toy.c written by Richard Kenner.

   It was later modified by Jonathan Bartlett whose changes have all

   been removed (by Tim Josling).

   Various bits and pieces were cloned from the GCC main tree, as

   GCC evolved, for COBOLForGCC, by Tim Josling.

   It was adapted to TREELANG by Tim Josling 2001.

   Updated to function-at-a-time by James A. Morrison, 2004.

   -----------------------------------------------------------------------

   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, 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; see the file COPYING3.  If not see

   <http://www.gnu.org/licenses/>.

   In other words, you are welcome to use, share and improve this program.

   You are forbidden to forbid anyone else to use, share and improve

   what you give them.   Help stamp out software-hoarding!

   -----------------------------------------------------------------------  */

/* Assumption: garbage collection is never called implicitly.  It will

   not be called 'at any time' when short of memory.  It will only be

   called explicitly at the end of each function.  This removes the

   need for a *lot* of bother to ensure everything is in the mark trees

   at all times.  */

/* Note, it is OK to use GCC extensions such as long long in a compiler front

   end.  This is because the GCC front ends are built using GCC.   */

/* GCC headers.  */

#include "config.h"

#include "system.h"

#include "coretypes.h"

#include "tm.h"

#include "tree.h"

#include "tree-dump.h"

#include "tree-iterator.h"

#include "tree-gimple.h"

#include "function.h"

#include "flags.h"

#include "output.h"

#include "ggc.h"

#include "toplev.h"

#include "varray.h"

#include "langhooks-def.h"

#include "langhooks.h"

#include "target.h"

#include "cgraph.h"

#include "treelang.h"

#include "treetree.h"

#include "opts.h"

extern int option_main;

extern char **file_names;

/* Types expected by gcc's garbage collector.

   These types exist to allow language front-ends to

   add extra information in gcc's parse tree data structure.

   But the treelang front end doesn't use them -- it has

   its own parse tree data structure.

   We define them here only to satisfy gcc's garbage collector.  */

/* Language-specific identifier information.  */

struct lang_identifier GTY(())

{

  struct tree_identifier common;

};

/* Language-specific tree node information.  */

union lang_tree_node

  GTY((desc ("TREE_CODE (&%h.generic) == IDENTIFIER_NODE")))

{

  union tree_node GTY ((tag ("0"),

                        desc ("tree_node_structure (&%h)")))

    generic;

  struct lang_identifier GTY ((tag ("1"))) identifier;

};

/* Language-specific type information.  */

struct lang_type GTY(())

{

  char junk; /* dummy field to ensure struct is not empty */

};

/* Language-specific declaration information.  */

struct lang_decl GTY(())

{

  char junk; /* dummy field to ensure struct is not empty */

};

struct language_function GTY(())

{

  char junk; /* dummy field to ensure struct is not empty */

};

static bool tree_mark_addressable (tree exp);

static tree tree_lang_type_for_size (unsigned precision, int unsignedp);

static tree tree_lang_type_for_mode (enum machine_mode mode, int unsignedp);

static tree tree_lang_unsigned_type (tree type_node);

static tree tree_lang_signed_type (tree type_node);

static tree tree_lang_signed_or_unsigned_type (int unsignedp, tree type);

/* Functions to keep track of the current scope.  */

static void pushlevel (int ignore);

static tree poplevel (int keep, int reverse, int functionbody);

static tree pushdecl (tree decl);

static tree* getstmtlist (void);

/* Langhooks.  */

static tree builtin_function (const char *name, tree type, int function_code,

                              enum built_in_class class,

                              const char *library_name,

                              tree attrs);

extern const struct attribute_spec treelang_attribute_table[];

static tree getdecls (void);

static int global_bindings_p (void);

static void insert_block (tree);

static void tree_push_type_decl (tree id, tree type_node);

static void treelang_expand_function (tree fndecl);

/* The front end language hooks (addresses of code for this front

   end).  These are not really very language-dependent, i.e.

   treelang, C, Mercury, etc. can all use almost the same definitions.  */

#undef LANG_HOOKS_MARK_ADDRESSABLE

#define LANG_HOOKS_MARK_ADDRESSABLE tree_mark_addressable

#undef LANG_HOOKS_SIGNED_TYPE

#define LANG_HOOKS_SIGNED_TYPE tree_lang_signed_type

#undef LANG_HOOKS_UNSIGNED_TYPE

#define LANG_HOOKS_UNSIGNED_TYPE tree_lang_unsigned_type

#undef LANG_HOOKS_SIGNED_OR_UNSIGNED_TYPE

#define LANG_HOOKS_SIGNED_OR_UNSIGNED_TYPE tree_lang_signed_or_unsigned_type

#undef LANG_HOOKS_TYPE_FOR_MODE

#define LANG_HOOKS_TYPE_FOR_MODE tree_lang_type_for_mode

#undef LANG_HOOKS_TYPE_FOR_SIZE

#define LANG_HOOKS_TYPE_FOR_SIZE tree_lang_type_for_size

#undef LANG_HOOKS_PARSE_FILE

#define LANG_HOOKS_PARSE_FILE treelang_parse_file

#undef LANG_HOOKS_ATTRIBUTE_TABLE

#define LANG_HOOKS_ATTRIBUTE_TABLE treelang_attribute_table

#undef LANG_HOOKS_CALLGRAPH_EXPAND_FUNCTION

#define LANG_HOOKS_CALLGRAPH_EXPAND_FUNCTION treelang_expand_function

/* #undef LANG_HOOKS_TYPES_COMPATIBLE_P

#define LANG_HOOKS_TYPES_COMPATIBLE_P hook_bool_tree_tree_true

*/

/* Hook routines and data unique to treelang.  */

#undef LANG_HOOKS_INIT

#define LANG_HOOKS_INIT treelang_init

#undef LANG_HOOKS_NAME

#define LANG_HOOKS_NAME "GNU treelang"

#undef LANG_HOOKS_FINISH

#define LANG_HOOKS_FINISH               treelang_finish

#undef LANG_HOOKS_INIT_OPTIONS

#define LANG_HOOKS_INIT_OPTIONS  treelang_init_options

#undef LANG_HOOKS_HANDLE_OPTION

#define LANG_HOOKS_HANDLE_OPTION treelang_handle_option

const struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;

/* Tree code type/name/code tables.  */

#define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,

const enum tree_code_class tree_code_type[] = {

#include "tree.def"

  tcc_exceptional

};

#undef DEFTREECODE

#define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,

const unsigned char tree_code_length[] = {

#include "tree.def"

};

#undef DEFTREECODE

#define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,

const char *const tree_code_name[] = {

#include "tree.def"

  "@@dummy"

};

#undef DEFTREECODE

/* Number of bits in int and char - accessed by front end.  */

unsigned int tree_code_int_size = SIZEOF_INT * HOST_BITS_PER_CHAR;

unsigned int tree_code_char_size = HOST_BITS_PER_CHAR;

/* Return the tree stuff for this type TYPE_NUM.  */

tree

tree_code_get_type (int type_num)

{

  switch (type_num)

    {

    case SIGNED_CHAR:

      return signed_char_type_node;

    case UNSIGNED_CHAR:

      return unsigned_char_type_node;

    case SIGNED_INT:

      return integer_type_node;

    case UNSIGNED_INT:

      return unsigned_type_node;

    case VOID_TYPE:

      return void_type_node;

    default:

      gcc_unreachable ();

    }

}

/* Output the code for the start of an if statement.  The test

   expression is EXP (true if not zero), and the stmt occurred at line

   LINENO in file FILENAME.  */

void

tree_code_if_start (tree exp, location_t loc)

{

  tree cond_exp, cond;

  cond_exp = fold_build2 (NE_EXPR, boolean_type_node, exp,

                          build_int_cst (TREE_TYPE (exp), 0));

  SET_EXPR_LOCATION (cond_exp, loc);

  cond = build3 (COND_EXPR, void_type_node, cond_exp, NULL_TREE,

                 NULL_TREE);

  SET_EXPR_LOCATION (cond, loc);

  append_to_statement_list_force (cond, getstmtlist ());

  pushlevel (0);

}

/* Output the code for the else of an if statement.  The else occurred

   at line LINENO in file FILENAME.  */

void

tree_code_if_else (location_t loc ATTRIBUTE_UNUSED)

{

  tree stmts = *getstmtlist ();

  tree block = poplevel (1, 0, 0);

  if (BLOCK_VARS (block))

    {

      tree bindexpr = build3 (BIND_EXPR, void_type_node, BLOCK_VARS (block),

                              stmts, block);

      stmts = alloc_stmt_list ();

      append_to_statement_list (bindexpr, &stmts);

    }

  TREE_OPERAND (STATEMENT_LIST_TAIL (*getstmtlist ())->stmt, 1) = stmts;

  pushlevel (0);

}

/* Output the code for the end_if an if statement.  The end_if (final brace)

   occurred at line LINENO in file FILENAME.  */

void

tree_code_if_end (location_t loc ATTRIBUTE_UNUSED)

{

  tree stmts = *getstmtlist ();

  tree block = poplevel (1, 0, 0);

  if (BLOCK_VARS (block))

    {

       tree bindexpr = build3 (BIND_EXPR, void_type_node, BLOCK_VARS (block),

                               stmts, block);

       stmts = alloc_stmt_list ();

       append_to_statement_list (bindexpr, &stmts);

    }

  TREE_OPERAND (STATEMENT_LIST_TAIL (*getstmtlist ())->stmt, 2) = stmts;

}

/* Create a function.  The prototype name is NAME, storage class is

   STORAGE_CLASS, type of return variable is RET_TYPE, parameter lists

   is PARMS, returns decl for this function.  */

tree

tree_code_create_function_prototype (unsigned char* chars,

                                     unsigned int storage_class,

                                     unsigned int ret_type,

                                     struct prod_token_parm_item* parms,

                                     location_t loc)

{

  tree id;

  struct prod_token_parm_item* parm;

  tree type_list = NULL_TREE;

  tree type_node;

  tree fn_type;

  tree fn_decl;

  tree parm_list = NULL_TREE;

  /* Build the type.  */

  id = get_identifier ((const char*)chars);

  for (parm = parms; parm; parm = parm->tp.par.next)

    {

      gcc_assert (parm->category == parameter_category);

      type_node = tree_code_get_type (parm->type);

      type_list = tree_cons (NULL_TREE, type_node, type_list);

    }

  /* Last parm if void indicates fixed length list (as opposed to

     printf style va_* list).  */

  type_list = tree_cons (NULL_TREE, void_type_node, type_list);

  /* The back end needs them in reverse order.  */

  type_list = nreverse (type_list);

  type_node = tree_code_get_type (ret_type);

  fn_type = build_function_type (type_node, type_list);

  id = get_identifier ((const char*)chars);

  fn_decl = build_decl (FUNCTION_DECL, id, fn_type);

  /* Nested functions not supported here.  */

  DECL_CONTEXT (fn_decl) = NULL_TREE;

  DECL_SOURCE_LOCATION (fn_decl) = loc;

  TREE_PUBLIC (fn_decl) = 0;

  DECL_EXTERNAL (fn_decl) = 0;

  TREE_STATIC (fn_decl) = 0;

  switch (storage_class)

    {

    case STATIC_STORAGE:

      break;

    case EXTERNAL_DEFINITION_STORAGE:

      TREE_PUBLIC (fn_decl) = 1;

      break;

    case EXTERNAL_REFERENCE_STORAGE:

      DECL_EXTERNAL (fn_decl) = 1;

      break;

    case AUTOMATIC_STORAGE:

    default:

      gcc_unreachable ();

    }

  /* Make the argument variable decls.  */

  for (parm = parms; parm; parm = parm->tp.par.next)

    {

      tree parm_decl = build_decl (PARM_DECL, get_identifier

                                   ((const char*) (parm->tp.par.variable_name)),

                                   tree_code_get_type (parm->type));

      /* Some languages have different nominal and real types.  */

      DECL_ARG_TYPE (parm_decl) = TREE_TYPE (parm_decl);

      gcc_assert (DECL_ARG_TYPE (parm_decl));

      gcc_assert (fn_decl);

      DECL_CONTEXT (parm_decl) = fn_decl;

      DECL_SOURCE_LOCATION (parm_decl) = loc;

      parm_list = chainon (parm_decl, parm_list);

    }

  /* Back into reverse order as the back end likes them.  */

  parm_list = nreverse (parm_list);

  DECL_ARGUMENTS (fn_decl) = parm_list;

  /* Save the decls for use when the args are referred to.  */

  for (parm = parms; parm_list;

       parm_list = TREE_CHAIN (parm_list),

        parm = parm->tp.par.next)

    {

      gcc_assert (parm); /* Too few.  */

      *parm->tp.par.where_to_put_var_tree = parm_list;

    }

  gcc_assert (!parm); /* Too many.  */

  /* Process declaration of function defined elsewhere.  */

  rest_of_decl_compilation (fn_decl, 1, 0);

  return fn_decl;

}

/* Output code for start of function; the decl of the function is in

   PREV_SAVED (as created by tree_code_create_function_prototype),

   the function is at line number LINENO in file FILENAME.  The

   parameter details are in the lists PARMS. Returns nothing.  */

void

tree_code_create_function_initial (tree prev_saved,

                                   location_t loc)

{

  tree fn_decl;

  tree resultdecl;

  fn_decl = prev_saved;

  gcc_assert (fn_decl);

  /* Output message if not -quiet.  */

  announce_function (fn_decl);

  /* This has something to do with forcing output also.  */

  pushdecl (fn_decl);

  /* Set current function for error msgs etc.  */

  current_function_decl = fn_decl;

  DECL_INITIAL (fn_decl) = error_mark_node;

  DECL_SOURCE_LOCATION (fn_decl) = loc;

  /* Create a DECL for the functions result.  */

  resultdecl =

    build_decl (RESULT_DECL, NULL_TREE, TREE_TYPE (TREE_TYPE (fn_decl)));

  DECL_CONTEXT (resultdecl) = fn_decl;

  DECL_ARTIFICIAL (resultdecl) = 1;

  DECL_IGNORED_P (resultdecl) = 1;

  DECL_SOURCE_LOCATION (resultdecl) = loc;

  DECL_RESULT (fn_decl) = resultdecl;

  /* Create a new level at the start of the function.  */

  pushlevel (0);

  TREE_STATIC (fn_decl) = 1;

}

/* Wrapup a function contained in file FILENAME, ending at line LINENO.  */

void

tree_code_create_function_wrapup (location_t loc)

{

  tree block;

  tree fn_decl;

  tree stmts = *getstmtlist ();

  fn_decl = current_function_decl;

  /* Pop the level.  */

  block = poplevel (1, 0, 1);

  /* And attach it to the function.  */

  DECL_SAVED_TREE (fn_decl) = build3 (BIND_EXPR, void_type_node,

                                      BLOCK_VARS (block),

                                      stmts, block);

  allocate_struct_function (fn_decl);

  cfun->function_end_locus = loc;

  /* Dump the original tree to a file.  */

  dump_function (TDI_original, fn_decl);

  /* Convert current function to GIMPLE for the middle end.  */

  gimplify_function_tree (fn_decl);

  dump_function (TDI_generic, fn_decl);

  /* We are not inside of any scope now.  */

  current_function_decl = NULL_TREE;

  cfun = NULL;

  /* Pass the current function off to the middle end.  */

  (void)cgraph_node (fn_decl);

  cgraph_finalize_function (fn_decl, false);

}

/* Create a variable.

   The storage class is STORAGE_CLASS (eg LOCAL).

   The name is CHARS/LENGTH.

   The type is EXPRESSION_TYPE (eg UNSIGNED_TYPE).

   The init tree is INIT.  */

tree

tree_code_create_variable (unsigned int storage_class,

                           unsigned char* chars,

                           unsigned int length,

                           unsigned int expression_type,

                           tree init,

                           location_t loc)

{

  tree var_type;

  tree var_id;

  tree var_decl;

  /* 1. Build the type.  */

  var_type = tree_code_get_type (expression_type);

  /* 2. Build the name.  */

  gcc_assert (chars[length] == 0); /* Should be null terminated.  */

  var_id = get_identifier ((const char*)chars);

  /* 3. Build the decl and set up init.  */

  var_decl = build_decl (VAR_DECL, var_id, var_type);

  /* 3a. Initialization.  */

  if (init)

    DECL_INITIAL (var_decl) = fold_convert (var_type, init);

  else

    DECL_INITIAL (var_decl) = NULL_TREE;

  gcc_assert (TYPE_SIZE (var_type) != 0); /* Did not calculate size.  */

  DECL_CONTEXT (var_decl) = current_function_decl;

  DECL_SOURCE_LOCATION (var_decl) = loc;

  DECL_EXTERNAL (var_decl) = 0;

  TREE_PUBLIC (var_decl) = 0;

  TREE_STATIC (var_decl) = 0;

  /* Set the storage mode and whether only visible in the same file.  */

  switch (storage_class)

    {

    case STATIC_STORAGE:

      TREE_STATIC (var_decl) = 1;

      break;

    case AUTOMATIC_STORAGE:

      break;

    case EXTERNAL_DEFINITION_STORAGE:

      TREE_PUBLIC (var_decl) = 1;

      break;

    case EXTERNAL_REFERENCE_STORAGE:

      DECL_EXTERNAL (var_decl) = 1;

      break;

    default:

      gcc_unreachable ();

    }

  TYPE_NAME (TREE_TYPE (var_decl)) = TYPE_NAME (var_type);

  return pushdecl (copy_node (var_decl));

}

/* Generate code for return statement.  Type is in TYPE, expression

   is in EXP if present.  */

void

tree_code_generate_return (tree type, tree exp)

{

  tree setret;

#ifdef ENABLE_CHECKING

  tree param;

  for (param = DECL_ARGUMENTS (current_function_decl);

       param;

       param = TREE_CHAIN (param))

    gcc_assert (DECL_CONTEXT (param) == current_function_decl);

#endif

  if (exp && TREE_TYPE (TREE_TYPE (current_function_decl)) != void_type_node)

    {

      setret = fold_build2 (MODIFY_EXPR, type,

                            DECL_RESULT (current_function_decl),

                            fold_convert (type, exp));

      TREE_SIDE_EFFECTS (setret) = 1;

      TREE_USED (setret) = 1;

      setret = build1 (RETURN_EXPR, type, setret);

      /* Use EXPR_LOCUS so we don't lose any information about the file we

         are compiling.  */

      SET_EXPR_LOCUS (setret, EXPR_LOCUS (exp));

    }

   else

     setret = build1 (RETURN_EXPR, type, NULL_TREE);

   append_to_statement_list_force (setret, getstmtlist ());

}

/* Output the code for this expression statement CODE.  */

void

tree_code_output_expression_statement (tree code, location_t loc)

{

  /* Output the line number information.  */

  SET_EXPR_LOCATION (code, loc);

  TREE_USED (code) = 1;

  TREE_SIDE_EFFECTS (code) = 1;

  /* put CODE into the code list.  */

  append_to_statement_list_force (code, getstmtlist ());

}

/* Return a tree for a constant integer value in the token TOK.  No

   size checking is done.  */

tree

tree_code_get_integer_value (unsigned char* chars, unsigned int length)

{

  long long int val = 0;

  unsigned int ix;

  unsigned int start = 0;

  int negative = 1;

  switch (chars[0])

    {

    case (unsigned char)'-':

      negative = -1;

      start = 1;

      break;

    case (unsigned char)'+':

      start = 1;

      break;

    default:

      break;

    }

  for (ix = start; ix < length; ix++)

    val = val * 10 + chars[ix] - (unsigned char)'0';

  val = val*negative;

  return build_int_cst_wide (start == 1 ?

                                integer_type_node : unsigned_type_node,

                             val & 0xffffffff, (val >> 32) & 0xffffffff);

}

/* Return the tree for an expression, type EXP_TYPE (see treetree.h)

   with tree type TYPE and with operands1 OP1, OP2 (maybe), OP3 (maybe).  */

tree

tree_code_get_expression (unsigned int exp_type,

                          tree type, tree op1, tree op2,

                          tree op3 ATTRIBUTE_UNUSED,

                          location_t loc)

{

  tree ret1;

  int operator;

  switch (exp_type)

    {

    case EXP_ASSIGN:

      gcc_assert (op1 && op2);

      operator = MODIFY_EXPR;

      ret1 = fold_build2 (operator, void_type_node, op1,

                          fold_convert (TREE_TYPE (op1), op2));

      break;

    case EXP_PLUS:

      operator = PLUS_EXPR;

      goto binary_expression;

    case EXP_MINUS:

      operator = MINUS_EXPR;

      goto binary_expression;

    case EXP_EQUALS:

      operator = EQ_EXPR;

      goto binary_expression;

    /* Expand a binary expression.  Ensure the operands are the right type.  */

    binary_expression:

      gcc_assert (op1 && op2);

      ret1  =  fold_build2 (operator, type,

                            fold_convert (type, op1),

                            fold_convert (type, op2));

      break;

      /* Reference to a variable.  This is dead easy, just return the

         decl for the variable.  If the TYPE is different than the

         variable type, convert it.  However, to keep accurate location

         information we wrap it in a NOP_EXPR is is easily stripped.  */

    case EXP_REFERENCE:

      gcc_assert (op1);

      TREE_USED (op1) = 1;

      if (type == TREE_TYPE (op1))

        ret1 = build1 (NOP_EXPR, type, op1);

      else

        ret1 = fold_convert (type, op1);

      break;

    case EXP_FUNCTION_INVOCATION:

      gcc_assert (op1);

      gcc_assert(TREE_TYPE (TREE_TYPE (op1)) == type);

      TREE_USED (op1) = 1;

      ret1 = build_function_call_expr(op1, op2);

      break;

    default:

      gcc_unreachable ();

    }

  /* Declarations already have a location and constants can be shared so they

     shouldn't a location set on them.  */

  if (! DECL_P (ret1) && ! TREE_CONSTANT (ret1))

    SET_EXPR_LOCATION (ret1, loc);

  return ret1;

}

/* Init parameter list and return empty list.  */

tree

tree_code_init_parameters (void)

{

  return NULL_TREE;

}