[llvm-branch-commits] [llvm] [AtomicExpand] Add bitcasts when expanding load atomic vector (PR #120716)

[Matt Arsenault via llvm-branch-commits]

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@@ -2066,9 +2066,18 @@ bool AtomicExpandImpl::expandAtomicOpToLibcall(
     I->replaceAllUsesWith(V);
   } else if (HasResult) {
     Value *V;
-    if (UseSizedLibcall)
-      V = Builder.CreateBitOrPointerCast(Result, I->getType());
-    else {
+    if (UseSizedLibcall) {
+      // Add bitcasts from Result's scalar type to I's <n x ptr> vector type
+      auto *PtrTy = dyn_cast<PointerType>(I->getType()->getScalarType());
+      auto *VTy = dyn_cast<VectorType>(I->getType());
+      if (VTy && PtrTy && !Result->getType()->isVectorTy()) {
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arsenm wrote:

There should probably be a utility for this somewhere 

https://github.com/llvm/llvm-project/pull/120716