For x86, STC still gives better results for optimise-for-size than
"simple" does. So use STC at -Os as well.
Is this okay for trunk?
Segher
2015-10-16 Segher Boessenkool <seg...@kernel.crashing.org>
PR rtl-optimization/67864
* common/config/i386/i386-common.c (ix86_option_optimization_table)
<OPT_freorder_blocks_algorithm_>: Use REORDER_BLOCKS_ALGORITHM_STC
at -Os and up.
---
gcc/common/config/i386/i386-common.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/gcc/common/config/i386/i386-common.c
b/gcc/common/config/i386/i386-common.c
index 79b2472..bb9f29c 100644
--- a/gcc/common/config/i386/i386-common.c
+++ b/gcc/common/config/i386/i386-common.c
@@ -1011,6 +1011,9 @@ static const struct default_options
ix86_option_optimization_table[] =
{ OPT_LEVELS_2_PLUS, OPT_free, NULL, 1 },
/* Enable function splitting at -O2 and higher. */
{ OPT_LEVELS_2_PLUS, OPT_freorder_blocks_and_partition, NULL, 1 },
+ /* The STC algorithm produces the smallest code at -Os, for x86. */
+ { OPT_LEVELS_2_PLUS, OPT_freorder_blocks_algorithm_, NULL,
+ REORDER_BLOCKS_ALGORITHM_STC },
/* Turn off -fschedule-insns by default. It tends to make the
problem with not enough registers even worse. */
{ OPT_LEVELS_ALL, OPT_fschedule_insns, NULL, 0 },
--
2.4.3
