[llvm] [GlobalISel] Allow Legalizer to lower volatile memcpy family. (PR #145997)

[Pete Chou via llvm-commits]

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@@ -10099,8 +10100,8 @@ LegalizerHelper::lowerMemCpyFamily(MachineInstr &MI, unsigned MaxLen) {
   }
 
   bool IsVolatile = MemOp->isVolatile();
-  // Don't try to optimize volatile.
-  if (IsVolatile)
+  // Don't try to optimize volatile when not allowed.
+  if (SkipVolatile && IsVolatile)
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petechou wrote:

@aemerson @arsenm 
Thanks for your comment. Changed to delete the check with an aarch64 lit update. The lit update seems ok as GISEL produces similar sequence as SDAG. Please help review. Thanks.

https://github.com/llvm/llvm-project/pull/145997