[llvm] [IR] Remove the AtomicMem*Inst helper classes (PR #138710)

[Philip Reames via llvm-commits]

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@@ -670,7 +670,7 @@ static bool tryToShorten(Instruction *DeadI, int64_t &DeadStart,
   assert(DeadSize > ToRemoveSize && "Can't remove more than original size");
 
   uint64_t NewSize = DeadSize - ToRemoveSize;
-  if (auto *AMI = dyn_cast<AtomicMemIntrinsic>(DeadI)) {
+  if (auto *AMI = dyn_cast<AnyMemIntrinsic>(DeadI); AMI && AMI->isAtomic()) {
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preames wrote:

It's not actually, but there's a DeadIntrinsic cast which is.  Adjusting.

https://github.com/llvm/llvm-project/pull/138710