[PATCH] D107370: [X86] Split Subtarget ISA / Security / Tuning Feature Flags Definitions. NFC

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: llvm/lib/Target/X86/X86.td:36-37
 
 def FeatureNOPL    : SubtargetFeature<"nopl", "HasNOPL", "true",
                                       "Enable NOPL instruction">;
 
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pengfei wrote:
> Should this be moved together with FeatureFast7ByteNOP etc.?
Feature NOPL isn't a tuning feature. It's architectural.


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Comment at: llvm/lib/Target/X86/X86.td:281-295
+// 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<
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pengfei wrote:
> These seem tuning features?
They have CPUID bits and they appear in HSWAdditionalFeatures rather than HSWTuning. and ICLAdditionalFeatures rather than ICLTuning.


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https://reviews.llvm.org/D107370