[llvm] [msan] Convert vector shadow to scalar before zext (PR #96722)

[Thurston Dang via llvm-commits]

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@@ -1398,6 +1399,8 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
     if (instrumentWithCalls(ConvertedShadow) &&
         SizeIndex < kNumberOfAccessSizes && !MS.CompileKernel) {
       FunctionCallee Fn = MS.MaybeWarningFn[SizeIndex];
+      // ZExt cannot convert between vector and scalar
+      ConvertedShadow = convertShadowToScalar(ConvertedShadow, IRB);
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thurstond wrote:

Baseline IR tests at https://github.com/llvm/llvm-project/pull/97611

I'll update this PR to show the corrected IR output

https://github.com/llvm/llvm-project/pull/96722