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| author | hubicka <hubicka@138bc75d-0d04-0410-961f-82ee72b054a4> | 2001-06-18 15:35:47 +0000 |
|---|---|---|
| committer | hubicka <hubicka@138bc75d-0d04-0410-961f-82ee72b054a4> | 2001-06-18 15:35:47 +0000 |
| commit | f6664feec514b2e3b3f36fb59c9b1b14dc5a52fc (patch) | |
| tree | 0803743d2349ea46ce205c05df7cae76a3374b1f /gcc/predict.def | |
| parent | 55af5e57a6fa3e4016d3723e03c3a1926ea9e9ee (diff) | |
| download | gcc-f6664feec514b2e3b3f36fb59c9b1b14dc5a52fc.tar.gz | |
* unroll.c: Include predict.h.
(unroll_loop): Drop prediction notes on preconditioning.
* predict.def (PRED_LOOP_PRECONDITIONG, PRED_LOOP_CONDITION):
New; add comments on the others.
* Makefile.in: (unroll.o): Add dependancy on predict.h.
* loop.c (strength_reduce): Fix branch prediction.
* stmt.c (emit_case_nodes): Optimize test whether index is in given
interval.
* predict.c (estimate_probability): Do not bail out early
when note is present.
(combine_predictions_for_insn): Fix note removal code.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@43441 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/predict.def')
| -rw-r--r-- | gcc/predict.def | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/gcc/predict.def b/gcc/predict.def index 01d87a4c3f0..ff8171bcc68 100644 --- a/gcc/predict.def +++ b/gcc/predict.def @@ -36,15 +36,47 @@ Boston, MA 02111-1307, USA. */ REG_BR_PROB_BASE / 2). */ +/* An combined heuristics using probability determined by first + matching heuristics from this list. */ DEF_PREDICTOR (PRED_FIRST_MATCH, "first match", PROB_ALWAYS) + +/* Mark unconditional jump as taken. */ DEF_PREDICTOR (PRED_UNCONDITIONAL, "unconditional jump", PROB_ALWAYS) + +/* Use number of loop iterations determined by loop unroller to set + probability. */ DEF_PREDICTOR (PRED_LOOP_ITERATIONS, "loop iterations", PROB_ALWAYS) + +/* Hints dropped by user via __builtin_expect feature. */ DEF_PREDICTOR (PRED_BUILTIN_EXPECT, "__builtin_expect", PROB_VERY_LIKELY) + +/* Branch to basic block containing call marked by noreturn attribute. */ DEF_PREDICTOR (PRED_NORETURN, "noreturn call", PROB_ALWAYS) + +/* Loopback edge is taken. */ DEF_PREDICTOR (PRED_LOOP_BRANCH, "loop branch", PROB_VERY_LIKELY) + +/* Edge causing loop to terminate is probably not taken. */ DEF_PREDICTOR (PRED_LOOP_EXIT, "loop exit", PROB_LIKELY) + +/* Condition emitted by preconditiong code to ensure that variable + setting number of iterations is greater than initial value of iterator. */ +DEF_PREDICTOR (PRED_LOOP_CONDITION, "loop condition", PROB_VERY_LIKELY) + +/* Preconditioning makes linear list of branches. */ +DEF_PREDICTOR (PRED_LOOP_PRECONDITIONING, "loop preconditioning", PROB_VERY_LIKELY) + +/* Copied condition for the first iteration of loop is probably true. */ DEF_PREDICTOR (PRED_LOOP_HEADER, "loop header", PROB_LIKELY) + +/* Pointers are usually not NULL. */ DEF_PREDICTOR (PRED_POINTER, "pointer", PROB_LIKELY) + +/* NE is probable, EQ not etc... */ DEF_PREDICTOR (PRED_OPCODE, "opcode", PROB_LIKELY) + +/* Branch guarding call is probably taken. */ DEF_PREDICTOR (PRED_CALL, "call", PROB_LIKELY) + +/* Branch causing function to terminate is probably not taken. */ DEF_PREDICTOR (PRED_ERROR_RETURN, "error return", PROB_LIKELY) |