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| author | Yuri Rumyantsev <ysrumyan@gmail.com> | 2016-01-11 12:07:31 +0000 |
|---|---|---|
| committer | Ilya Enkovich <ienkovich@gcc.gnu.org> | 2016-01-11 12:07:31 +0000 |
| commit | ca90b1ed9ac7e9aaacb3ef0eb055d2f594d30493 (patch) | |
| tree | aff7cf99fbd76cee5e9f06139145d6518bc63045 /gcc/ifcvt.c | |
| parent | b4934671aed067e0a8c3ac3fcc5871dd27a706ed (diff) | |
| download | gcc-ca90b1ed9ac7e9aaacb3ef0eb055d2f594d30493.zip gcc-ca90b1ed9ac7e9aaacb3ef0eb055d2f594d30493.tar.gz gcc-ca90b1ed9ac7e9aaacb3ef0eb055d2f594d30493.tar.bz2 | |
re PR rtl-optimization/68920 (Undesirable if-conversion for a rarely taken branch)
gcc/
2016-01-11 Yuri Rumyantsev <ysrumyan@gmail.com>
PR rtl-optimization/68920
* config/i386/i386.c (ix86_option_override_internal): Restrict number
of conditional moves for RTL if-conversion to 1 for
TARGET_ONE_IF_CONV_INSN.
* config/i386/i386.h (TARGET_ONE_IF_CONV_INSN): New macros.
* config/i386/x86-tune.def (X86_TUNE_ONE_IF_CONV_INSN): New macros.
* params.def (PARAM_MAX_RTL_IF_CONVERSION_INSNS) : Introduce new
parameter to restirct number of conditional moves for
RTL if-conversion.
* doc/invoke.texi (max-rtl-if-conversion-insns): Document it.
* ifcvt.c (bb_ok_for_noce_convert_multiple_sets): Limit number of
conditionl moves.
gcc/testsuite/
2016-01-11 Yuri Rumyantsev <ysrumyan@gmail.com>
PR rtl-optimization/68920
* gcc.dg/ifcvt-4.c: Add "--param max-rtl-if-conversion-insns=3" option
for ix86 targets.
* gcc.dg/ifcvt-5.c: New test.
From-SVN: r232220
Diffstat (limited to 'gcc/ifcvt.c')
| -rw-r--r-- | gcc/ifcvt.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/gcc/ifcvt.c b/gcc/ifcvt.c index 67b10cf..723ea3e 100644 --- a/gcc/ifcvt.c +++ b/gcc/ifcvt.c @@ -44,6 +44,7 @@ #include "shrink-wrap.h" #include "rtl-iter.h" #include "ifcvt.h" +#include "params.h" #ifndef MAX_CONDITIONAL_EXECUTE #define MAX_CONDITIONAL_EXECUTE \ @@ -3242,6 +3243,8 @@ bb_ok_for_noce_convert_multiple_sets (basic_block test_bb, { rtx_insn *insn; unsigned count = 0; + unsigned param = PARAM_VALUE (PARAM_MAX_RTL_IF_CONVERSION_INSNS); + unsigned limit = MIN (ii->branch_cost, param); FOR_BB_INSNS (test_bb, insn) { @@ -3277,8 +3280,8 @@ bb_ok_for_noce_convert_multiple_sets (basic_block test_bb, /* FORNOW: Our cost model is a count of the number of instructions we would if-convert. This is suboptimal, and should be improved as part of a wider rework of branch_cost. */ - if (count > ii->branch_cost) - return FALSE; + if (count > limit) + return false; return count > 0; } @@ -3823,7 +3826,6 @@ cond_move_process_if_block (struct noce_if_info *if_info) } num_updated_if_blocks++; - success_p = TRUE; done: @@ -4810,7 +4812,6 @@ find_if_case_1 (basic_block test_bb, edge then_edge, edge else_edge) num_true_changes++; num_updated_if_blocks++; - return TRUE; } |