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| author | Bernd Schmidt <bernds@codesourcery.com> | 2010-04-26 21:17:17 +0000 |
|---|---|---|
| committer | Bernd Schmidt <bernds@gcc.gnu.org> | 2010-04-26 21:17:17 +0000 |
| commit | 823ff7b434a663ce1d060987027c7dee360ab9d2 (patch) | |
| tree | 1c9584cc811e8ac51bda3af95fc87e52d368d92a /gcc/fwprop.c | |
| parent | 1637c2e1ba572a859a9e99dd2ff16ddf88d8b3f7 (diff) | |
| download | gcc-823ff7b434a663ce1d060987027c7dee360ab9d2.zip gcc-823ff7b434a663ce1d060987027c7dee360ab9d2.tar.gz gcc-823ff7b434a663ce1d060987027c7dee360ab9d2.tar.bz2 | |
df-problems.c (df_simulate_initialize_forwards): Set, don't clear, bits for artificial defs at the top of the block.
* df-problems.c (df_simulate_initialize_forwards): Set, don't clear,
bits for artificial defs at the top of the block.
* fwprop.c (single_def_use_enter_block): Don't call it.
From-SVN: r158750
Diffstat (limited to 'gcc/fwprop.c')
| -rw-r--r-- | gcc/fwprop.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/gcc/fwprop.c b/gcc/fwprop.c index 7ac64aa..6e65093 100644 --- a/gcc/fwprop.c +++ b/gcc/fwprop.c @@ -228,7 +228,10 @@ single_def_use_enter_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED, process_uses (df_get_artificial_uses (bb_index), DF_REF_AT_TOP); process_defs (df_get_artificial_defs (bb_index), DF_REF_AT_TOP); - df_simulate_initialize_forwards (bb, local_lr); + + /* We don't call df_simulate_initialize_forwards, as it may overestimate + the live registers if there are unused artificial defs. We prefer + liveness to be underestimated. */ FOR_BB_INSNS (bb, insn) if (INSN_P (insn)) |