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| author | Jan Hubicka <hubicka@ucw.cz> | 2017-11-17 18:47:36 +0100 |
|---|---|---|
| committer | Jan Hubicka <hubicka@gcc.gnu.org> | 2017-11-17 17:47:36 +0000 |
| commit | 650fe7323c11e5e116e34d88028909b1221e2cc8 (patch) | |
| tree | c5efcdde9c45c7831beb37712307f991d8211360 /gcc/predict.c | |
| parent | db16c1841a09f60bbdf2bb825e7e790a437f83c7 (diff) | |
| download | gcc-650fe7323c11e5e116e34d88028909b1221e2cc8.zip gcc-650fe7323c11e5e116e34d88028909b1221e2cc8.tar.gz gcc-650fe7323c11e5e116e34d88028909b1221e2cc8.tar.bz2 | |
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
Diffstat (limited to 'gcc/predict.c')
| -rw-r--r-- | gcc/predict.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/gcc/predict.c b/gcc/predict.c index 7404f1a..7e40f77 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) { |