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predict.c (determine_unlikely_bbs): Set cgraph node count to 0 when entry block was promoted unlikely.

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* predict.c (determine_unlikely_bbs): Set cgraph node count to 0
	when entry block was promoted unlikely.
	(estimate_bb_frequencies): Increase frequency scale.
	* profile-count.h (profile_count): Export precision info.
	* gcc.dg/tree-ssa/dump-2.c: Fixup template for profile precision
	changes.
	* gcc.dg/tree-ssa/pr77445-2.c: Fixup template for profile precision
	changes.

From-SVN: r254888
This commit is contained in:
Jan Hubicka 2017-11-17 18:47:36 +01:00 • committed by Jan Hubicka
parent db16c1841a
commit 650fe7323c
6 changed files with 27 additions and 3 deletions
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7
gcc/ChangeLog
View file

@ -1,3 +1,10 @@
2017-11-17 Jan Hubicka <hubicka@ucw.cz>
* predict.c (determine_unlikely_bbs): Set cgraph node count to 0
when entry block was promoted unlikely.
(estimate_bb_frequencies): Increase frequency scale.
* profile-count.h (profile_count): Export precision info.
2017-11-17 Jan Hubicka <hubicka@ucw.cz>
* tree-tailcall.c (eliminate_tail_call): Be more careful about not

10
gcc/predict.c
View file

@ -3542,6 +3542,8 @@ determine_unlikely_bbs ()
bb->index, e->dest->index);
e->probability = profile_probability::never ();
}
if (ENTRY_BLOCK_PTR_FOR_FN (cfun)->count == profile_count::zero ())
cgraph_node::get (current_function_decl)->count = profile_count::zero ();
}
/* Estimate and propagate basic block frequencies using the given branch
@ -3565,7 +3567,11 @@ estimate_bb_frequencies (bool force)
{
real_values_initialized = 1;
real_br_prob_base = REG_BR_PROB_BASE;
real_bb_freq_max = BB_FREQ_MAX;
/* Scaling frequencies up to maximal profile count may result in
frequent overflows especially when inlining loops.
Small scalling results in unnecesary precision loss. Stay in
the half of the (exponential) range. */
real_bb_freq_max = (uint64_t)1 << (profile_count::n_bits / 2);
real_one_half = sreal (1, -1);
real_inv_br_prob_base = sreal (1) / real_br_prob_base;
real_almost_one = sreal (1) - real_inv_br_prob_base;
@ -3610,6 +3616,8 @@ estimate_bb_frequencies (bool force)
freq_max = BLOCK_INFO (bb)->frequency;
freq_max = real_bb_freq_max / freq_max;
if (freq_max < 16)
freq_max = 16;
cfun->cfg->count_max = profile_count::uninitialized ();
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun), NULL, next_bb)
{

2
gcc/profile-count.h
View file

@ -605,11 +605,13 @@ class sreal;
class GTY(()) profile_count
{
public:
/* Use 62bit to hold basic block counters. Should be at least
64bit. Although a counter cannot be negative, we use a signed
type to hold various extra stages. */
static const int n_bits = 61;
private:
static const uint64_t max_count = ((uint64_t) 1 << n_bits) - 2;
static const uint64_t uninitialized_count = ((uint64_t) 1 << n_bits) - 1;

7
gcc/testsuite/ChangeLog
View file

@ -1,3 +1,10 @@
2017-11-17 Jan Hubicka <hubicka@ucw.cz>
* gcc.dg/tree-ssa/dump-2.c: Fixup template for profile precision
changes.
* gcc.dg/tree-ssa/pr77445-2.c: Fixup template for profile precision
changes.
2017-11-17 Nathan Sidwell <nathan@acm.org>
* g++.dg/pr82836.C: Fix for c++17.

2
gcc/testsuite/gcc.dg/tree-ssa/dump-2.c
View file

@ -6,4 +6,4 @@ int f(void)
return 0;
}
/* { dg-final { scan-tree-dump "<bb \[0-9\]> \\\[local count: 10000\\\]:" "optimized" } } */
/* { dg-final { scan-tree-dump "<bb \[0-9\]> \\\[local count: " "optimized" } } */

2
gcc/testsuite/gcc.dg/tree-ssa/pr77445-2.c
View file

@ -120,7 +120,7 @@ enum STATES FMS( u8 **in , u32 *transitions) {
profile estimation stage. But the number of inconsistencies should not
increase much. */
/* { dg-final { scan-tree-dump "Jumps threaded: 1\[1-9\]" "thread1" } } */
/* { dg-final { scan-tree-dump-times "Invalid sum" 2 "thread1" } } */
/* { dg-final { scan-tree-dump-times "Invalid sum" 3 "thread1" } } */
/* { dg-final { scan-tree-dump-not "not considered" "thread1" } } */
/* { dg-final { scan-tree-dump-not "not considered" "thread2" } } */
/* { dg-final { scan-tree-dump-not "not considered" "thread3" } } */