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predict.c (set_even_probabilities): Include also unlikely_count in calculation.

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2018-12-31  Martin Liska  <mliska@suse.cz>

	* predict.c (set_even_probabilities): Include also
	unlikely_count in calculation.
	(combine_predictions_for_bb): Consider also HOT and
	COLD labels predictions.
	* predict.def (PRED_HOT_LABEL): Move it just after
	__builtin_expect_with_probability predictor.
	(PRED_COLD_LABEL): Likewise.
2018-12-31  Martin Liska  <mliska@suse.cz>

	* g++.dg/predict-2.C: New test.
	* g++.dg/predict-3.C: New test.
	* g++.dg/predict-4.C: New test.
	* gcc.dg/tree-ssa/attr-hotcold-2.c: Adjust test-case.

From-SVN: r267485
This commit is contained in:
Martin Liska 2018-12-31 14:46:08 +01:00 committed by Martin Liska
parent 41ee4e75ab
commit b3282dfe1a
8 changed files with 89 additions and 12 deletions
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10
gcc/ChangeLog
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@ -1,3 +1,13 @@
2018-12-31 Martin Liska <mliska@suse.cz>
* predict.c (set_even_probabilities): Include also
unlikely_count in calculation.
(combine_predictions_for_bb): Consider also HOT and
COLD labels predictions.
* predict.def (PRED_HOT_LABEL): Move it just after
__builtin_expect_with_probability predictor.
(PRED_COLD_LABEL): Likewise.
2018-12-30 Jan Hubicka <hubicka@ucw.cz>
* x86-tune.def: Enable inter_unit_moves_to_vec for generic.

15
gcc/predict.c
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@ -878,11 +878,18 @@ set_even_probabilities (basic_block bb,
profile_probability prob
= profile_probability::from_reg_br_prob_base (p);
profile_probability remainder = prob.invert ();
remainder -= profile_probability::very_unlikely ()
.apply_scale (unlikely_count, 1);
int count = nedges - unlikely_count - 1;
gcc_assert (count >= 0);
profile_probability even = remainder.apply_scale (1, count);
if (prediction->ep_edge == e)
e->probability = prob;
else if (unlikely_edges != NULL && unlikely_edges->contains (e))
e->probability = profile_probability::very_unlikely ();
else
e->probability = remainder.apply_scale (1, nedges - 1);
e->probability = even;
}
else
e->probability = profile_probability::never ();
@ -1217,10 +1224,12 @@ combine_predictions_for_bb (basic_block bb, bool dry_run)
if (preds)
for (pred = *preds; pred; pred = pred->ep_next)
{
if (pred->ep_probability <= PROB_VERY_UNLIKELY)
if (pred->ep_probability <= PROB_VERY_UNLIKELY
|| pred->ep_predictor == PRED_COLD_LABEL)
unlikely_edges.add (pred->ep_edge);
if (pred->ep_probability >= PROB_VERY_LIKELY
|| pred->ep_predictor == PRED_BUILTIN_EXPECT)
|| pred->ep_predictor == PRED_BUILTIN_EXPECT
|| pred->ep_predictor == PRED_HOT_LABEL)
likely_edges.add (pred);
}

15
gcc/predict.def
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@ -78,6 +78,14 @@ DEF_PREDICTOR (PRED_BUILTIN_EXPECT_WITH_PROBABILITY,
"__builtin_expect_with_probability", PROB_UNINITIALIZED,
PRED_FLAG_FIRST_MATCH)
/* Branches to hot labels are likely. */
DEF_PREDICTOR (PRED_HOT_LABEL, "hot label", HITRATE (90),
PRED_FLAG_FIRST_MATCH)
/* Branches to cold labels are extremely unlikely. */
DEF_PREDICTOR (PRED_COLD_LABEL, "cold label", HITRATE (90),
PRED_FLAG_FIRST_MATCH)
/* Use number of loop iterations guessed by the contents of the loop. */
DEF_PREDICTOR (PRED_LOOP_ITERATIONS_GUESSED, "guessed loop iterations",
PROB_UNINITIALIZED, PRED_FLAG_FIRST_MATCH)
@ -171,13 +179,6 @@ DEF_PREDICTOR (PRED_LOOP_GUARD, "loop guard", HITRATE (73), 0)
DEF_PREDICTOR (PRED_LOOP_GUARD_WITH_RECURSION, "loop guard with recursion",
HITRATE (85), 0)
/* Branches to hot labels are likely. */
DEF_PREDICTOR (PRED_HOT_LABEL, "hot label", HITRATE (85), 0)
/* Branches to cold labels are extremely unlikely. */
DEF_PREDICTOR (PRED_COLD_LABEL, "cold label", PROB_VERY_LIKELY,
PRED_FLAG_FIRST_MATCH)
/* The following predictors are used in Fortran. */
/* Branch leading to an integer overflow are extremely unlikely. */

7
gcc/testsuite/ChangeLog
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@ -1,3 +1,10 @@
2018-12-31 Martin Liska <mliska@suse.cz>
* g++.dg/predict-2.C: New test.
* g++.dg/predict-3.C: New test.
* g++.dg/predict-4.C: New test.
* gcc.dg/tree-ssa/attr-hotcold-2.c: Adjust test-case.
2018-12-30 H.J. Lu <hongjiu.lu@intel.com>
PR testsuite/88639

16
gcc/testsuite/g++.dg/predict-2.C Normal file
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@ -0,0 +1,16 @@
/* { dg-do compile } */
/* { dg-options "-O2 -fdump-tree-profile_estimate -std=c++11" } */
int a, b, c;
void
bar()
{
if (a == 123)
[[likely]] c = 5;
else
c = 5;
}
/* { dg-final { scan-tree-dump "first match heuristics: 90.00%" "profile_estimate"} } */
/* { dg-final { scan-tree-dump "hot label heuristics of edge .*->.*: 90.00%" "profile_estimate"} } */

17
gcc/testsuite/g++.dg/predict-3.C Normal file
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@ -0,0 +1,17 @@
/* { dg-do compile } */
/* { dg-options "-O2 -fdump-tree-profile_estimate -std=c++11" } */
int a, b, c;
void
bar ()
{
switch (a)
{
case 3: __builtin_puts("a"); break;
case 42: __builtin_puts("e"); break;
[[likely]] case 333: __builtin_puts("i"); break;
}
}
/* { dg-final { scan-tree-dump "default.*3.33%.*case 3.*3.33%.*case 42.*3.33%.*case 333.*90.00%" "profile_estimate"} } */

17
gcc/testsuite/g++.dg/predict-4.C Normal file
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@ -0,0 +1,17 @@
/* { dg-do compile } */
/* { dg-options "-O2 -fdump-tree-profile_estimate -std=c++11" } */
int a, b, c;
void
bar ()
{
switch (a)
{
case 3: __builtin_puts("a"); break;
[[unlikely]] case 42: __builtin_puts("e"); break;
[[likely]] case 333: __builtin_puts("i"); break;
}
}
/* { dg-final { scan-tree-dump "default.*4.98%.*case 3.*4.98%.*case 42.*0.05%.*case 333.*90.00%" "profile_estimate"} } */

4
gcc/testsuite/gcc.dg/tree-ssa/attr-hotcold-2.c
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@ -19,9 +19,9 @@ void f(int x, int y)
/* { dg-final { scan-tree-dump-times "hot label heuristics" 1 "profile_estimate" } } */
/* { dg-final { scan-tree-dump-times "cold label heuristics" 1 "profile_estimate" } } */
/* { dg-final { scan-tree-dump-times "combined heuristics: 0\\\..*" 1 "profile_estimate" } } */
/* { dg-final { scan-tree-dump-times "combined heuristics: 10.00%" 1 "profile_estimate" } } */
/* Note: we're attempting to match some number > 6000, i.e. > 60%.
The exact number ought to be tweekable without having to juggle
the testcase around too much. */
/* { dg-final { scan-tree-dump-times "combined heuristics: \[6-9\]\[0-9\]\\\..*" 1 "profile_estimate" } } */
/* { dg-final { scan-tree-dump-times "combined heuristics: 90.00%" 1 "profile_estimate" } } */