[PATCH] D41895: [X86] Another attempt at support prefer-vector-width function attribute

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: lib/Target/X86/X86Subtarget.cpp:260
+  if (PreferVectorWidthOverride)
+    PreferVectorWidth = PreferVectorWidthOverride;
+  else if (Prefer256Bit)
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RKSimon wrote:
> craig.topper wrote:
> > RKSimon wrote:
> > > Do we need to assert for a sane value here (else in X86TargetMachine.cpp)?
> > What do you consider a sane value? There's no bounds checking on the attribute coming in.
> assert(IsPowerOf2(PreferVectorWidthOverride) && PreferVectorWidthOverride >= 128 )?
It comes from an unchecked command line argument passed to clang that was intended to be target independent. There's no guarantee of any particular value or range.


https://reviews.llvm.org/D41895