freebsd-dev/contrib/gcc/c-semantics.c
2007-05-19 01:19:51 +00:00

169 lines
4.3 KiB
C

/* This file contains the definitions and documentation for the common
tree codes used in the GNU C and C++ compilers (see c-common.def
for the standard codes).
Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005
Free Software Foundation, Inc.
Written by Benjamin Chelf (chelf@codesourcery.com).
This file is part of GCC.
GCC 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 2, or (at your option) any later
version.
GCC 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 GCC; see the file COPYING. If not, write to the Free
Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
#include "function.h"
#include "splay-tree.h"
#include "varray.h"
#include "c-common.h"
#include "except.h"
/* In order for the format checking to accept the C frontend
diagnostic framework extensions, you must define this token before
including toplev.h. */
#define GCC_DIAG_STYLE __gcc_cdiag__
#include "toplev.h"
#include "flags.h"
#include "ggc.h"
#include "rtl.h"
#include "output.h"
#include "timevar.h"
#include "predict.h"
#include "tree-inline.h"
#include "tree-gimple.h"
#include "langhooks.h"
/* Create an empty statement tree rooted at T. */
tree
push_stmt_list (void)
{
tree t;
t = alloc_stmt_list ();
TREE_CHAIN (t) = cur_stmt_list;
cur_stmt_list = t;
return t;
}
/* Finish the statement tree rooted at T. */
tree
pop_stmt_list (tree t)
{
tree u = cur_stmt_list, chain;
/* Pop statement lists until we reach the target level. The extra
nestings will be due to outstanding cleanups. */
while (1)
{
chain = TREE_CHAIN (u);
TREE_CHAIN (u) = NULL_TREE;
if (t == u)
break;
u = chain;
}
cur_stmt_list = chain;
/* If the statement list is completely empty, just return it. This is
just as good small as build_empty_stmt, with the advantage that
statement lists are merged when they appended to one another. So
using the STATEMENT_LIST avoids pathological buildup of EMPTY_STMT_P
statements. */
if (TREE_SIDE_EFFECTS (t))
{
tree_stmt_iterator i = tsi_start (t);
/* If the statement list contained exactly one statement, then
extract it immediately. */
if (tsi_one_before_end_p (i))
{
u = tsi_stmt (i);
tsi_delink (&i);
free_stmt_list (t);
t = u;
}
}
return t;
}
/* Build a generic statement based on the given type of node and
arguments. Similar to `build_nt', except that we set
EXPR_LOCATION to be the current source location. */
/* ??? This should be obsolete with the lineno_stmt productions
in the grammar. */
tree
build_stmt (enum tree_code code, ...)
{
tree ret;
int length, i;
va_list p;
bool side_effects;
va_start (p, code);
ret = make_node (code);
TREE_TYPE (ret) = void_type_node;
length = TREE_CODE_LENGTH (code);
SET_EXPR_LOCATION (ret, input_location);
/* TREE_SIDE_EFFECTS will already be set for statements with
implicit side effects. Here we make sure it is set for other
expressions by checking whether the parameters have side
effects. */
side_effects = false;
for (i = 0; i < length; i++)
{
tree t = va_arg (p, tree);
if (t && !TYPE_P (t))
side_effects |= TREE_SIDE_EFFECTS (t);
TREE_OPERAND (ret, i) = t;
}
TREE_SIDE_EFFECTS (ret) |= side_effects;
va_end (p);
return ret;
}
/* Let the back-end know about DECL. */
void
emit_local_var (tree decl)
{
/* Create RTL for this variable. */
if (!DECL_RTL_SET_P (decl))
{
if (DECL_HARD_REGISTER (decl))
/* The user specified an assembler name for this variable.
Set that up now. */
rest_of_decl_compilation (decl, 0, 0);
else
expand_decl (decl);
}
}
/* Create a CASE_LABEL_EXPR tree node and return it. */
tree
build_case_label (tree low_value, tree high_value, tree label_decl)
{
return build_stmt (CASE_LABEL_EXPR, low_value, high_value, label_decl);
}