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| author | Teresa Johnson <tejohnson@google.com> | 2013-10-03 05:06:05 +0000 |
|---|---|---|
| committer | Teresa Johnson <tejohnson@gcc.gnu.org> | 2013-10-03 05:06:05 +0000 |
| commit | 79221839a3c9c0e8a4cf5ea130bcf24062ee3995 (patch) | |
| tree | d85c8dce4505e035ecaa38597a50dd80df80808e /gcc/predict.c | |
| parent | 697786593677771f060fdb99dc1114d7bb48f372 (diff) | |
| download | gcc-79221839a3c9c0e8a4cf5ea130bcf24062ee3995.zip gcc-79221839a3c9c0e8a4cf5ea130bcf24062ee3995.tar.gz gcc-79221839a3c9c0e8a4cf5ea130bcf24062ee3995.tar.bz2 | |
predict.c (probably_never_executed): New function.
2013-10-02 Teresa Johnson <tejohnson@google.com>
* predict.c (probably_never_executed): New function.
(probably_never_executed_bb_p): Invoke probably_never_executed.
(probably_never_executed_edge_p): Ditto.
* bb-reorder.c (find_rarely_executed_basic_blocks_and_crossing_edges):
Treat profile insanities conservatively.
From-SVN: r203152
Diffstat (limited to 'gcc/predict.c')
| -rw-r--r-- | gcc/predict.c | 33 |
1 files changed, 19 insertions, 14 deletions
diff --git a/gcc/predict.c b/gcc/predict.c index 4815e75..2909117 100644 --- a/gcc/predict.c +++ b/gcc/predict.c @@ -226,23 +226,26 @@ maybe_hot_edge_p (edge e) } -/* Return true in case BB is probably never executed. */ -bool -probably_never_executed_bb_p (struct function *fun, const_basic_block bb) +/* Return true if profile COUNT and FREQUENCY, or function FUN static + node frequency reflects never being executed. */ + +static bool +probably_never_executed (struct function *fun, + gcov_type count, int frequency) { gcc_checking_assert (fun); if (profile_status_for_function (fun) == PROFILE_READ) { - if ((bb->count * 4 + profile_info->runs / 2) / profile_info->runs > 0) + if ((count * 4 + profile_info->runs / 2) / profile_info->runs > 0) return false; - if (!bb->frequency) + if (!frequency) return true; if (!ENTRY_BLOCK_PTR->frequency) return false; if (ENTRY_BLOCK_PTR->count && ENTRY_BLOCK_PTR->count < REG_BR_PROB_BASE) { - return (RDIV (bb->frequency * ENTRY_BLOCK_PTR->count, + return (RDIV (frequency * ENTRY_BLOCK_PTR->count, ENTRY_BLOCK_PTR->frequency) < REG_BR_PROB_BASE / 4); } @@ -256,19 +259,21 @@ probably_never_executed_bb_p (struct function *fun, const_basic_block bb) } +/* Return true in case BB is probably never executed. */ + +bool +probably_never_executed_bb_p (struct function *fun, const_basic_block bb) +{ + return probably_never_executed (fun, bb->count, bb->frequency); +} + + /* Return true in case edge E is probably never executed. */ bool probably_never_executed_edge_p (struct function *fun, edge e) { - gcc_checking_assert (fun); - if (profile_info && flag_branch_probabilities) - return ((e->count + profile_info->runs / 2) / profile_info->runs) == 0; - if ((!profile_info || !flag_branch_probabilities) - && (cgraph_get_node (fun->decl)->frequency - == NODE_FREQUENCY_UNLIKELY_EXECUTED)) - return true; - return false; + return probably_never_executed (fun, e->count, EDGE_FREQUENCY (e)); } /* Return true if NODE should be optimized for size. */ |