[llvm] [IA] Fix crash when dealing with deinterleave(interleave) (PR #150713)

[Craig Topper via llvm-commits]

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@@ -534,10 +537,12 @@ bool InterleavedAccessImpl::lowerInterleavedStore(
   if (SI) {
     LLVM_DEBUG(dbgs() << "IA: Found an interleaved store: " << *Store << "\n");
   } else {
+    Value *MaskOperand = getMaskOperand(II);
+    if (!MaskOperand)
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topperc wrote:

I we do it this way, I would use an `assert` here.

https://github.com/llvm/llvm-project/pull/150713