/* Loop header copying on trees.
- Copyright (C) 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
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
+Free Software Foundation; either version 3, or (at your option) any
later version.
GCC is distributed in the hope that it will be useful, but WITHOUT
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. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
if (get_call_expr_in (last))
return false;
- *limit -= estimate_num_insns (last);
+ *limit -= estimate_num_insns (last, &eni_size_weights);
if (*limit < 0)
return false;
}
static unsigned int
copy_loop_headers (void)
{
- unsigned i;
+ loop_iterator li;
struct loop *loop;
basic_block header;
edge exit, entry;
loop_optimizer_init (LOOPS_HAVE_PREHEADERS
| LOOPS_HAVE_SIMPLE_LATCHES);
- if (!current_loops)
- return 0;
+ if (number_of_loops () <= 1)
+ {
+ loop_optimizer_finalize ();
+ return 0;
+ }
#ifdef ENABLE_CHECKING
- verify_loop_structure (current_loops);
+ verify_loop_structure ();
#endif
bbs = XNEWVEC (basic_block, n_basic_blocks);
copied_bbs = XNEWVEC (basic_block, n_basic_blocks);
bbs_size = n_basic_blocks;
- for (i = 1; i < current_loops->num; i++)
+ FOR_EACH_LOOP (li, loop, 0)
{
/* Copy at most 20 insns. */
int limit = 20;
- loop = current_loops->parray[i];
- if (!loop)
- continue;
header = loop->header;
/* If the loop is already a do-while style one (either because it was
continue;
}
+ /* If the loop has the form "for (i = j; i < j + 10; i++)" then
+ this copying can introduce a case where we rely on undefined
+ signed overflow to eliminate the preheader condition, because
+ we assume that "j < j + 10" is true. We don't want to warn
+ about that case for -Wstrict-overflow, because in general we
+ don't warn about overflow involving loops. Prevent the
+ warning by setting TREE_NO_WARNING. */
+ if (warn_strict_overflow > 0)
+ {
+ unsigned int i;
+
+ for (i = 0; i < n_bbs; ++i)
+ {
+ block_stmt_iterator bsi;
+
+ for (bsi = bsi_start (copied_bbs[i]);
+ !bsi_end_p (bsi);
+ bsi_next (&bsi))
+ {
+ tree stmt = bsi_stmt (bsi);
+ if (TREE_CODE (stmt) == COND_EXPR)
+ TREE_NO_WARNING (stmt) = 1;
+ else if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT)
+ {
+ tree rhs = GIMPLE_STMT_OPERAND (stmt, 1);
+ if (COMPARISON_CLASS_P (rhs))
+ TREE_NO_WARNING (stmt) = 1;
+ }
+ }
+ }
+ }
+
/* Ensure that the latch and the preheader is simple (we know that they
are not now, since there was the loop exit condition. */
split_edge (loop_preheader_edge (loop));