[PATCH] D129647: [X86] Use generic tuning for "x86-64" if "tune-cpu" is not specified

[Craig Topper via Phabricator via llvm-commits]

craig.topper added a comment.

This comment in X86.td is wrong now

  // NOTE: As a default tuning, "generic" aims to produce code optimized for the   
  // most common X86 processors. The tunings might be changed over time. It is     
  // recommended to use "x86-64" in lit tests for consistency.  



================
Comment at: llvm/lib/Target/X86/X86TargetMachine.cpp:257
       CPUAttr.isValid() ? CPUAttr.getValueAsString() : (StringRef)TargetCPU;
-  StringRef TuneCPU =
-      TuneAttr.isValid() ? TuneAttr.getValueAsString() : (StringRef)CPU;
+  StringRef TuneCPU = TuneAttr.isValid() ? TuneAttr.getValueAsString()
+                      : CPU == "x86-64"  ? "generic"
----------------
Probably worth a comment here


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D129647/new/

https://reviews.llvm.org/D129647