mirror/gcc
2
0
Fork 0
mirror of git://gcc.gnu.org/git/gcc.git synced 2025-03-20 09:00:37 +08:00
Code Issues Packages Projects Releases Wiki Activity

re PR tree-optimization/20913 (copy-prop does not fold conditionals)

Browse Source 
gcc/
	PR tree-optimization/20913
	* tree-ssa-copy.c (copy_prop_visit_cond_stmt): Fold COND_EXPR.

testsuite/
	PR tree-optimization/20913
	* gcc.dg/tree-ssa/pr20913.c: New.

From-SVN: r98090
This commit is contained in:
Kazu Hirata 2005-04-13 15:28:55 +00:00 committed by Kazu Hirata
parent e22a7bcf26
commit 9fb6cbd90e
4 changed files with 45 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
gcc/ChangeLog
View File

@ -1,3 +1,8 @@
2005-04-13 Kazu Hirata <kazu@cs.umass.edu>
PR tree-optimization/20913
* tree-ssa-copy.c (copy_prop_visit_cond_stmt): Fold COND_EXPR.
2005-04-13 Julian Brown <julian@codesourcery.com>
* config/elfos.h (MAKE_DECL_ONE_ONLY): Redefined to stop DECL_WEAK from

5
gcc/testsuite/ChangeLog
View File

@ -1,3 +1,8 @@
2005-04-13 Kazu Hirata <kazu@cs.umass.edu>
PR tree-optimization/20913
* gcc.dg/tree-ssa/pr20913.c: New.
2005-04-13 Volker Reichelt <reichelt@igpm.rwth-aachen.de>
PR c++/13744

25
gcc/testsuite/gcc.dg/tree-ssa/pr20913.c Normal file
View File

@ -0,0 +1,25 @@
/* PR tree-optimization/20913
COPY-PROP did not fold COND_EXPR, blocking some copy propagation
opportunities. */
/* { dg-do compile } */
/* { dg-options "-O2 -fno-tree-dominator-opts -fdump-tree-copyprop1-details" } */
int
foo (int a, int b, int c, int d)
{
int x, y;
b = a;
if (a == b)
x = c;
else
x = d;
if (x == c)
return a;
else
return b;
}
/* { dg-final { scan-tree-dump-times "with if \\(1\\)" 2 "copyprop1"} } */

13
gcc/tree-ssa-copy.c
View File

@ -626,9 +626,16 @@ copy_prop_visit_cond_stmt (tree stmt, edge *taken_edge_p)
print_generic_stmt (dump_file, cond, 0);
}
*taken_edge_p = find_taken_edge (bb_for_stmt (stmt), cond);
if (*taken_edge_p)
retval = SSA_PROP_INTERESTING;
/* We can fold COND only and get a useful result only when we
have the same SSA_NAME on both sides of a comparison
operator. */
if (TREE_CODE (TREE_OPERAND (cond, 0)) == SSA_NAME
&& TREE_OPERAND (cond, 0) == TREE_OPERAND (cond, 1))
{
*taken_edge_p = find_taken_edge (bb_for_stmt (stmt), fold (cond));
if (*taken_edge_p)
retval = SSA_PROP_INTERESTING;
}
/* Restore the original operands. */
for (i = 0; i < NUM_USES (uses); i++)