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authorJan Hubicka <jh@suse.cz>2004-09-26 01:21:07 +0200
committerJan Hubicka <hubicka@gcc.gnu.org>2004-09-25 23:21:07 +0000
commit5db0241f0c3d3130a502d9c6a59713302a1377bf (patch)
tree4392e10fd036d9f719e777e135df217f0ac7eee9
parentffe2e220bdb8fee858045b645601923656864cc5 (diff)
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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
-rw-r--r--gcc/ChangeLog5
-rw-r--r--gcc/profile.c18
2 files changed, 20 insertions, 3 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 0ba761f..7cd05ad 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2004-09-26 Jan Hubicka <jh@suse.cz>
+
+ * profile.c (compute_branch_probabilities): Use REG_BR_PROB notes
+ when re-constructing profile previously invalidated by loop.
+
2004-09-25 Dale Johannesen <dalej@apple.com>
* tree-gimple.c: Move GIMPLE definition...
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;