From 650fe7323c11e5e116e34d88028909b1221e2cc8 Mon Sep 17 00:00:00 2001 From: Jan Hubicka Date: Fri, 17 Nov 2017 18:47:36 +0100 Subject: [PATCH] predict.c (determine_unlikely_bbs): Set cgraph node count to 0 when entry block was promoted unlikely. * 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 --- gcc/ChangeLog | 7 +++++++ gcc/predict.c | 10 +++++++++- gcc/profile-count.h | 2 ++ gcc/testsuite/ChangeLog | 7 +++++++ gcc/testsuite/gcc.dg/tree-ssa/dump-2.c | 2 +- gcc/testsuite/gcc.dg/tree-ssa/pr77445-2.c | 2 +- 6 files changed, 27 insertions(+), 3 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 5ab422c917a..3864ff2fa05 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2017-11-17 Jan Hubicka + + * 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 * tree-tailcall.c (eliminate_tail_call): Be more careful about not diff --git a/gcc/predict.c b/gcc/predict.c index 7404f1af1fa..7e40f7773f1 100644 --- a/gcc/predict.c +++ b/gcc/predict.c @@ -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) { diff --git a/gcc/profile-count.h b/gcc/profile-count.h index 90d1bc747ee..66a217d39fd 100644 --- a/gcc/profile-count.h +++ b/gcc/profile-count.h @@ -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; diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 9592080cea8..149ed11a502 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,10 @@ +2017-11-17 Jan Hubicka + + * 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 * g++.dg/pr82836.C: Fix for c++17. diff --git a/gcc/testsuite/gcc.dg/tree-ssa/dump-2.c b/gcc/testsuite/gcc.dg/tree-ssa/dump-2.c index 20f99c2df12..a1ab635906b 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/dump-2.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/dump-2.c @@ -6,4 +6,4 @@ int f(void) return 0; } -/* { dg-final { scan-tree-dump " \\\[local count: 10000\\\]:" "optimized" } } */ +/* { dg-final { scan-tree-dump " \\\[local count: " "optimized" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr77445-2.c b/gcc/testsuite/gcc.dg/tree-ssa/pr77445-2.c index 88e3b946fe4..eecfc4b195a 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/pr77445-2.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr77445-2.c @@ -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" } } */ -- 2.30.2