diff options
Diffstat (limited to 'lib/Target/X86/X86.td')
| -rw-r--r-- | lib/Target/X86/X86.td | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/lib/Target/X86/X86.td b/lib/Target/X86/X86.td index 8fcc8e31d5d4..d2f650cf8f47 100644 --- a/lib/Target/X86/X86.td +++ b/lib/Target/X86/X86.td @@ -273,6 +273,16 @@ def FeatureFastSHLDRotate "fast-shld-rotate", "HasFastSHLDRotate", "true", "SHLD can be used as a faster rotate">; +// Ivy Bridge and newer processors have enhanced REP MOVSB and STOSB (aka +// "string operations"). See "REP String Enhancement" in the Intel Software +// Development Manual. This feature essentially means that REP MOVSB will copy +// using the largest available size instead of copying bytes one by one, making +// it at least as fast as REPMOVS{W,D,Q}. +def FeatureERMSB + : SubtargetFeature< + "ermsb", "HasERMSB", "true", + "REP MOVS/STOS are fast">; + //===----------------------------------------------------------------------===// // X86 processors supported. //===----------------------------------------------------------------------===// @@ -498,6 +508,7 @@ def HSWFeatures : ProcessorFeatures<IVBFeatures.Value, [ FeatureAVX2, FeatureBMI, FeatureBMI2, + FeatureERMSB, FeatureFMA, FeatureLZCNT, FeatureMOVBE, |