[llvm] [AArch64][GlobalISel] Add support for widening vector store elements to s8. (PR #121170)

[Amara Emerson via llvm-commits]

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@@ -3022,8 +3022,18 @@ LegalizerHelper::widenScalar(MachineInstr &MI, unsigned TypeIdx, LLT WideTy) {
       return UnableToLegalize;
 
     LLT Ty = MRI.getType(MI.getOperand(0).getReg());
-    if (!Ty.isScalar())
-      return UnableToLegalize;
+    if (!Ty.isScalar()) {
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aemerson wrote:

I can put an assert, but it shouldn't be valid to widenScalarOrElt on a pointer vector?

https://github.com/llvm/llvm-project/pull/121170