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| author | Jan Hubicka <jh@suse.cz> | 2004-09-26 01:21:07 +0200 |
|---|---|---|
| committer | Jan Hubicka <hubicka@gcc.gnu.org> | 2004-09-25 23:21:07 +0000 |
| commit | 5db0241f0c3d3130a502d9c6a59713302a1377bf (patch) | |
| tree | 4392e10fd036d9f719e777e135df217f0ac7eee9 /gcc/profile.c | |
| parent | ffe2e220bdb8fee858045b645601923656864cc5 (diff) | |
| download | gcc-5db0241f0c3d3130a502d9c6a59713302a1377bf.zip gcc-5db0241f0c3d3130a502d9c6a59713302a1377bf.tar.gz gcc-5db0241f0c3d3130a502d9c6a59713302a1377bf.tar.bz2 | |
profile.c (compute_branch_probabilities): Use REG_BR_PROB notes when re-constructing profile previously invalidated by loop.
* profile.c (compute_branch_probabilities): Use REG_BR_PROB notes
when re-constructing profile previously invalidated by loop.
From-SVN: r88115
Diffstat (limited to 'gcc/profile.c')
| -rw-r--r-- | gcc/profile.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/gcc/profile.c b/gcc/profile.c index 3f48be6..39d0493 100644 --- a/gcc/profile.c +++ b/gcc/profile.c @@ -557,12 +557,24 @@ compute_branch_probabilities (void) num_branches++; } } - /* Otherwise distribute the probabilities evenly so we get sane - sum. Use simple heuristics that if there are normal edges, + /* Otherwise try to preserve the existing REG_BR_PROB probabilities + tree based profile guessing put into code. */ + else if (profile_status == PROFILE_ABSENT + && !ir_type () + && bb->succ && bb->succ->succ_next + && (note = find_reg_note (BB_END (bb), REG_BR_PROB, 0))) + { + int prob = INTVAL (XEXP (note, 0)); + + BRANCH_EDGE (bb)->probability = prob; + FALLTHRU_EDGE (bb)->probability = REG_BR_PROB_BASE - prob; + } + /* As a last resolt, distribute the probabilities evenly. + Use simple heuristics that if there are normal edges, give all abnormals frequency of 0, otherwise distribute the frequency over abnormals (this is the case of noreturn calls). */ - else + else if (profile_status == PROFILE_ABSENT) { int total = 0; |