diff options
| author | dehao <dehao@138bc75d-0d04-0410-961f-82ee72b054a4> | 2012-05-08 10:01:44 +0000 |
|---|---|---|
| committer | dehao <dehao@138bc75d-0d04-0410-961f-82ee72b054a4> | 2012-05-08 10:01:44 +0000 |
| commit | fd757b763e4afa80c8663061807858592005834a (patch) | |
| tree | 732faa7f65751352d1a617a0eb9ad11d9033c84f /gcc/predict.def | |
| parent | 128e3935ca7fd502266fd72f8da7373ccb1990ee (diff) | |
| download | gcc-fd757b763e4afa80c8663061807858592005834a.tar.gz | |
2012-05-08 Dehao Chen <dehao@google.com>
gcc/
* predict.c (find_qualified_ssa_name): New
(find_ssa_name_in_expr): New
(find_ssa_name_in_assign_stmt): New
(is_comparison_with_loop_invariant_p): New
(is_bound_expr_similar): New
(predict_iv_comparison): New
(predict_loops): Add heuristic for loop-nested branches that compare an
induction variable to a loop bound variable.
* predict.def (PRED_LOOP_IV_COMPARE): New macro
testsuite/
* gcc.dg/predict-1.c: Check if LOOP_IV_COMPARE static predict
heuristic is working properly.
* gcc.dg/predict-2.c: Likewise.
* gcc/dg/predict-3.c: Likewise.
* gcc/dg/predict-4.c: Likewise.
* gcc/dg/predict-5.c: Likewise.
* gcc/dg/predict-6.c: Likewise.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@187277 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/predict.def')
| -rw-r--r-- | gcc/predict.def | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/gcc/predict.def b/gcc/predict.def index 4b3e87aa568..591bb1caf58 100644 --- a/gcc/predict.def +++ b/gcc/predict.def @@ -116,3 +116,13 @@ DEF_PREDICTOR (PRED_NULL_RETURN, "null return", HITRATE (90), 0) /* Branches to a mudflap bounds check are extremely unlikely. */ DEF_PREDICTOR (PRED_MUDFLAP, "mudflap check", PROB_VERY_LIKELY, 0) + +/* Branches to compare induction variable to a loop bound is + extremely likely. */ +DEF_PREDICTOR (PRED_LOOP_IV_COMPARE_GUESS, "guess loop iv compare", + PROB_VERY_LIKELY, 0) + +/* Use number of loop iterations determined by # of iterations analysis + to set probability of branches that compares IV to loop bound variable. */ +DEF_PREDICTOR (PRED_LOOP_IV_COMPARE, "loop iv compare", PROB_VERY_LIKELY, + PRED_FLAG_FIRST_MATCH) |