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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/config | |
| parent | b4934671aed067e0a8c3ac3fcc5871dd27a706ed (diff) | |
| download | gcc-ca90b1ed9ac7e9aaacb3ef0eb055d2f594d30493.tar.gz | |
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/config')
| -rw-r--r-- | gcc/config/i386/i386.c | 7 | ||||
| -rw-r--r-- | gcc/config/i386/i386.h | 2 | ||||
| -rw-r--r-- | gcc/config/i386/x86-tune.def | 5 |
3 files changed, 14 insertions, 0 deletions
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index aac0847db7e..c0b2cce4f3f 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -5343,6 +5343,13 @@ ix86_option_override_internal (bool main_args_p, opts->x_param_values, opts_set->x_param_values); + /* Restrict number of if-converted SET insns to 1. */ + if (TARGET_ONE_IF_CONV_INSN) + maybe_set_param_value (PARAM_MAX_RTL_IF_CONVERSION_INSNS, + 1, + opts->x_param_values, + opts_set->x_param_values); + /* Enable sw prefetching at -O3 for CPUS that prefetching is helpful. */ if (opts->x_flag_prefetch_loop_arrays < 0 && HAVE_prefetch diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h index befed85721c..dcaa011a2be 100644 --- a/gcc/config/i386/i386.h +++ b/gcc/config/i386/i386.h @@ -499,6 +499,8 @@ extern unsigned char ix86_tune_features[X86_TUNE_LAST]; ix86_tune_features[X86_TUNE_ADJUST_UNROLL] #define TARGET_AVOID_FALSE_DEP_FOR_BMI \ ix86_tune_features[X86_TUNE_AVOID_FALSE_DEP_FOR_BMI] +#define TARGET_ONE_IF_CONV_INSN \ + ix86_tune_features[X86_TUNE_ONE_IF_CONV_INSN] /* Feature tests against the various architecture variations. */ enum ix86_arch_indices { diff --git a/gcc/config/i386/x86-tune.def b/gcc/config/i386/x86-tune.def index 88ed50aa860..9d25e51d407 100644 --- a/gcc/config/i386/x86-tune.def +++ b/gcc/config/i386/x86-tune.def @@ -550,3 +550,8 @@ DEF_TUNE (X86_TUNE_PROMOTE_QI_REGS, "promote_qi_regs", 0) unrolling small loop less important. For, such architectures we adjust the unroll factor so that the unrolled loop fits the loop buffer. */ DEF_TUNE (X86_TUNE_ADJUST_UNROLL, "adjust_unroll_factor", m_BDVER3 | m_BDVER4) + +/* X86_TUNE_ONE_IF_CONV_INSNS: Restrict a number of set insns to be + if-converted to one. */ +DEF_TUNE (X86_TUNE_ONE_IF_CONV_INSN, "one_if_conv_insn", + m_SILVERMONT | m_KNL | m_INTEL | m_CORE_ALL | m_GENERIC) |