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

[Pengfei Wang via Phabricator via llvm-commits]

pengfei 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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Should this be moved together with FeatureFast7ByteNOP etc.?


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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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These seem tuning features?


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Comment at: llvm/lib/Target/X86/X86.td:307
+// mitigate potential Spectre v2 attacks against them.
+def FeatureRetpolineIndirectCalls
+    : SubtargetFeature<
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Is it better if we can make security features and tuning features begin with e.g., MitigationXXXX and TuningXXX respectively?


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  https://reviews.llvm.org/D107370/new/

https://reviews.llvm.org/D107370