[clang] [llvm] [SROA] Vector promote some memsets (PR #133301)

[via llvm-commits]

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@@ -1170,10 +1191,23 @@ class AllocaSlices::SliceBuilder : public PtrUseVisitor<SliceBuilder> {
     if (!IsOffsetKnown)
       return PI.setAborted(&II);
 
+    auto IsSplittable = [&]() {
+      FixedVectorType *VTy = getVectorTypeFor(II, DL);
+      Type *ATy = AS.AI.getAllocatedType();
+
+      if (!Length)
+        return false;
+      if (!VTy)
+        return true;
+      if (DL.getTypeAllocSize(VTy) != DL.getTypeAllocSize(ATy))
+        return true;
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macurtis-amd wrote:

Cleaned up the code. Hopefully better now.

https://github.com/llvm/llvm-project/pull/133301