decl.c

gcc-2.95.3 Linux下最常用的C编译器

	  IDENTIFIER_LABEL_VALUE (DECL_NAME (label)) = 0;

	  /* Put the labels into the "variables" of the
	     top-level block, so debugger can see them.  */
	  TREE_CHAIN (label) = BLOCK_VARS (block);
	  BLOCK_VARS (block) = label;
	}
#endif
    }

  /* Pop the current level, and free the structure for reuse.  */

  {
    register struct binding_level *level = current_binding_level;
    current_binding_level = current_binding_level->level_chain;

    level->level_chain = free_binding_level;
    free_binding_level = level;
  }

  /* Dispose of the block that we just made inside some higher level.  */
  if (functionbody)
    DECL_INITIAL (current_function_decl) = block;
  else if (block)
    {
      if (!block_previously_created)
        current_binding_level->blocks
          = chainon (current_binding_level->blocks, block);
    }
  /* If we did not make a block for the level just exited,
     any blocks made for inner levels
     (since they cannot be recorded as subblocks in that level)
     must be carried forward so they will later become subblocks
     of something else.  */
  else if (subblocks)
    current_binding_level->blocks
      = chainon (current_binding_level->blocks, subblocks);

  /* Set the TYPE_CONTEXTs for all of the tagged types belonging to this
     binding contour so that they point to the appropriate construct, i.e.
     either to the current FUNCTION_DECL node, or else to the BLOCK node
     we just constructed.

     Note that for tagged types whose scope is just the formal parameter
     list for some function type specification, we can't properly set
     their TYPE_CONTEXTs here, because we don't have a pointer to the
     appropriate FUNCTION_TYPE node readily available to us.  For those
     cases, the TYPE_CONTEXTs of the relevant tagged type nodes get set
     in `grokdeclarator' as soon as we have created the FUNCTION_TYPE
     node which will represent the "scope" for these "parameter list local"
     tagged types.
  */

  if (block)
    TREE_USED (block) = 1;
  return block;
}

void
maybe_pushlevels (pc)
     int pc;
{
  while (pending_local_decls != NULL_TREE &&
	 DECL_LOCAL_START_PC (pending_local_decls) <= pc)
    {
      tree *ptr = &pending_local_decls;
      tree decl = *ptr;
      int end_pc = DECL_LOCAL_END_PC (decl);

      while (*ptr != NULL_TREE
	     && DECL_LOCAL_START_PC (*ptr) <= pc
	     && DECL_LOCAL_END_PC (*ptr) == end_pc)
	ptr = &TREE_CHAIN (*ptr);
      pending_local_decls = *ptr;
      *ptr = NULL_TREE;

      /* Force non-nested range to be nested in current range. */
      if (end_pc > current_binding_level->end_pc)
	end_pc = current_binding_level->end_pc;

      pushlevel (1);
      expand_start_bindings (0);
      current_binding_level->end_pc = end_pc;
      
      current_binding_level->names = decl;
      for ( ; decl != NULL_TREE;  decl = TREE_CHAIN (decl))
	{
	  push_jvm_slot (DECL_LOCAL_SLOT_NUMBER (decl), decl);
	}
    }
}

void
maybe_poplevels (pc)
     int pc;
{
  while (current_binding_level->end_pc <= pc)
    {
      expand_end_bindings (getdecls (), 1, 0);
      poplevel (1, 0, 0);
    }
}

/* Insert BLOCK at the end of the list of subblocks of the
   current binding level.  This is used when a BIND_EXPR is expanded,
   to handle the BLOCK node inside the BIND_EXPR.  */

void
insert_block (block)
     tree block;
{
  TREE_USED (block) = 1;
  abort ();
  current_binding_level->blocks
    = chainon (current_binding_level->blocks, block);
}

/* Set the BLOCK node for the innermost scope
   (the one we are currently in).  */

void
set_block (block)
     register tree block;
{
  current_binding_level->this_block = block;
}

/* integrate_decl_tree calls this function. */

void
copy_lang_decl (node)
     tree node;
{
  int lang_decl_size
    = TREE_CODE (node) == VAR_DECL ? sizeof (struct lang_decl_var)
    : sizeof (struct lang_decl);
  struct lang_decl *x = (struct lang_decl *) oballoc (lang_decl_size);
  bcopy ((PTR) DECL_LANG_SPECIFIC (node), (PTR) x, lang_decl_size);
  DECL_LANG_SPECIFIC (node) = x;
}

/* If DECL has a cleanup, build and return that cleanup here.
   This is a callback called by expand_expr.  */

tree
maybe_build_cleanup (decl)
  tree decl ATTRIBUTE_UNUSED;
{
  /* There are no cleanups in Java (I think).  */
  return NULL_TREE;
}

void
give_name_to_locals (jcf)
     JCF *jcf;
{
  int i, n = DECL_LOCALVARIABLES_OFFSET (current_function_decl);
  tree parm;
  pending_local_decls = NULL_TREE;
  if (n == 0)
    return;
  JCF_SEEK (jcf, n);
  n = JCF_readu2 (jcf);
  for (i = 0; i < n; i++)
    {
      int start_pc = JCF_readu2 (jcf);
      int length = JCF_readu2 (jcf);
      int name_index = JCF_readu2 (jcf);
      int signature_index = JCF_readu2 (jcf);
      int slot = JCF_readu2 (jcf);
      tree name = get_name_constant (jcf, name_index);
      tree type = parse_signature (jcf, signature_index);
      if (slot < DECL_ARG_SLOT_COUNT (current_function_decl)
	  && start_pc == 0
	  && length == DECL_CODE_LENGTH (current_function_decl))
	{
	  tree decl = TREE_VEC_ELT (decl_map, slot);
	  DECL_NAME (decl) = name;
	  DECL_ASSEMBLER_NAME (decl) = name;
	  if (TREE_CODE (decl) != PARM_DECL || TREE_TYPE (decl) != type)
	    warning ("bad type in parameter debug info");
	}
      else
	{
	  tree *ptr;
	  int end_pc = start_pc + length;
	  tree decl = build_decl (VAR_DECL, name, type);
	  if (end_pc > DECL_CODE_LENGTH (current_function_decl))
	    {
	      warning_with_decl (decl,
			 "bad PC range for debug info for local `%s'");
	      end_pc = DECL_CODE_LENGTH (current_function_decl);
	    }
	  DECL_LANG_SPECIFIC (decl)
	    = (struct lang_decl *) permalloc (sizeof (struct lang_decl_var));
	  DECL_LOCAL_SLOT_NUMBER (decl) = slot;
	  DECL_LOCAL_START_PC (decl) = start_pc;
	  DECL_LOCAL_END_PC (decl) = end_pc;

	  /* Now insert the new decl in the proper place in
	     pending_local_decls.  We are essentially doing an insertion sort,
	     which works fine, since the list input will normally already
	     be sorted. */
	  ptr = &pending_local_decls;
	  while (*ptr != NULL_TREE
		 && (DECL_LOCAL_START_PC (*ptr) > start_pc
		     || (DECL_LOCAL_START_PC (*ptr) == start_pc
			 && DECL_LOCAL_END_PC (*ptr) < end_pc)))
	    ptr = &TREE_CHAIN (*ptr);
	  TREE_CHAIN (decl) = *ptr;
	  *ptr = decl;
	}
    }

  pending_local_decls = nreverse (pending_local_decls);

  /* Fill in default names for the parameters. */ 
  for (parm = DECL_ARGUMENTS (current_function_decl), i = 0;
       parm != NULL_TREE;  parm = TREE_CHAIN (parm), i++)
    {
      if (DECL_NAME (parm) == NULL_TREE)
	{
	  int arg_i = METHOD_STATIC (current_function_decl) ? i+1 : i;
	  if (arg_i == 0)
	    DECL_NAME (parm) = get_identifier ("this");
	  else
	    {
	      char buffer[12];
	      sprintf (buffer, "ARG_%d", arg_i);
	      DECL_NAME (parm) = get_identifier (buffer);
	    }
	  DECL_ASSEMBLER_NAME (parm) = DECL_NAME (parm);
	}
    }
}

tree
build_result_decl (fndecl)
  tree fndecl;
{
  tree restype = TREE_TYPE (TREE_TYPE (fndecl));
  /* To be compatible with C_PROMOTING_INTEGER_TYPE_P in cc1/cc1plus. */
  if (INTEGRAL_TYPE_P (restype)
      && TYPE_PRECISION (restype) < TYPE_PRECISION (integer_type_node))
    restype = integer_type_node;
  return (DECL_RESULT (fndecl) = build_decl (RESULT_DECL, NULL_TREE, restype));
}

void
complete_start_java_method (fndecl)
  tree fndecl;
{
  if (! flag_emit_class_files)
    {
      /* Initialize the RTL code for the function.  */
      init_function_start (fndecl, input_filename, lineno);

      /* Set up parameters and prepare for return, for the function.  */
      expand_function_start (fndecl, 0);
    }

  /* Allocate further tree nodes temporarily during compilation
     of this function only.  */
  temporary_allocation ();

#if 0
      /* If this fcn was already referenced via a block-scope `extern' decl (or
         an implicit decl), propagate certain information about the usage. */
      if (TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (current_function_decl)))
        TREE_ADDRESSABLE (current_function_decl) = 1;

#endif

  if (METHOD_STATIC (fndecl) && ! METHOD_PRIVATE (fndecl)
      && ! flag_emit_class_files
      && ! CLASS_INTERFACE (TYPE_NAME (current_class)))
    {
      tree clas = DECL_CONTEXT (fndecl);
      tree init = build (CALL_EXPR, void_type_node,
			 build_address_of (soft_initclass_node),
			 build_tree_list (NULL_TREE, build_class_ref (clas)),
			 NULL_TREE);
      TREE_SIDE_EFFECTS (init) = 1;
      expand_expr_stmt (init);
    }

  /* Push local variables. Function compiled from source code are
     using a different local variables management, and for them,
     pushlevel shouldn't be called from here.  */
  if (!CLASS_FROM_SOURCE_P (DECL_CONTEXT (fndecl)))
    {
      pushlevel (2);
      if (! flag_emit_class_files)
	expand_start_bindings (1);
    }

  if (METHOD_SYNCHRONIZED (fndecl) && ! flag_emit_class_files)
    {
      /* Warp function body with a monitorenter plus monitorexit cleanup. */
      tree enter, exit, lock;
      if (METHOD_STATIC (fndecl))
	lock = build_class_ref (DECL_CONTEXT (fndecl));
      else
	lock = DECL_ARGUMENTS (fndecl);
      BUILD_MONITOR_ENTER (enter, lock);
      BUILD_MONITOR_EXIT (exit, lock);
      if (!CLASS_FROM_SOURCE_P (DECL_CONTEXT (fndecl)))
	{
	  expand_expr_stmt (enter);
	  expand_decl_cleanup (NULL_TREE, exit);
	}
      else
	{
	  tree function_body = DECL_FUNCTION_BODY (fndecl);
	  tree body = BLOCK_EXPR_BODY (function_body);
	  lock = build (WITH_CLEANUP_EXPR, void_type_node,
			enter,  NULL_TREE, exit);
	  TREE_SIDE_EFFECTS (lock) = 1;
	  lock = build (COMPOUND_EXPR, TREE_TYPE (body), lock, body);
	  TREE_SIDE_EFFECTS (lock) = 1;
	  lock = build1 (CLEANUP_POINT_EXPR, TREE_TYPE (body), lock);
	  TREE_SIDE_EFFECTS (lock) = 1;
	  BLOCK_EXPR_BODY (function_body) = lock;
	}
    }
}

void
start_java_method (fndecl)
     tree fndecl;
{
  tree tem, *ptr;
  int i;

  current_function_decl = fndecl;
  announce_function (fndecl);

  i = DECL_MAX_LOCALS(fndecl) + DECL_MAX_STACK(fndecl);
  decl_map = make_tree_vec (i);
  type_map = (tree *) oballoc (i * sizeof (tree));

  pushlevel (1);  /* Push parameters. */

  ptr = &DECL_ARGUMENTS (fndecl);
  for (tem = TYPE_ARG_TYPES (TREE_TYPE (fndecl)), i = 0;
       tem != end_params_node; tem = TREE_CHAIN (tem), i++)
    {
      tree parm_name = NULL_TREE, parm_decl;
      tree parm_type = TREE_VALUE (tem);
      if (i >= DECL_MAX_LOCALS(fndecl))
	fatal ("function has more parameters than local slots");

      parm_decl = build_decl (PARM_DECL, parm_name, parm_type);
      DECL_CONTEXT (parm_decl) = fndecl;
#ifdef PROMOTE_PROTOTYPES
      if (TYPE_PRECISION (parm_type) < TYPE_PRECISION (integer_type_node)
	  && INTEGRAL_TYPE_P (parm_type))
	parm_type = integer_type_node;
#endif
      DECL_ARG_TYPE (parm_decl) = parm_type;

      *ptr = parm_decl;
      ptr = &TREE_CHAIN (parm_decl);

      /* Add parm_decl to the decl_map. */
      push_jvm_slot (i, parm_decl);

      type_map[i] = TREE_TYPE (parm_decl);
      if (TYPE_IS_WIDE (TREE_TYPE (parm_decl)))
	{
	  i++;
	  type_map[i] = void_type_node;
	}
    }
  *ptr = NULL_TREE;
  DECL_ARG_SLOT_COUNT (current_function_decl) = i;

  while (i < DECL_MAX_LOCALS(fndecl))
    type_map[i++] = NULL_TREE;

  build_result_decl (fndecl);
  complete_start_java_method (fndecl);
}

void
end_java_method ()
{
  tree fndecl = current_function_decl;
  int flag_asynchronous_exceptions = asynchronous_exceptions;

  expand_end_bindings (getdecls (), 1, 0);
  /* pop out of function */
  poplevel (1, 1, 0);

  /* pop out of its parameters */
  poplevel (1, 0, 1);

  BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;

  emit_handlers ();

  /* Generate rtl for function exit.  */
  expand_function_end (input_filename, lineno, 0);

  /* FIXME: If the current method contains any exception handlers,
     force asynchronous_exceptions: this is necessary because signal
     handlers in libjava may throw exceptions.  This is far from being
     a perfect solution, but it's better than doing nothing at all.*/
  if (catch_clauses)
    asynchronous_exceptions = 1;

  /* Run the optimizers and output assembler code for this function. */
  rest_of_compilation (fndecl);

  current_function_decl = NULL_TREE;
  permanent_allocation (1);
  asynchronous_exceptions = flag_asynchronous_exceptions;
}