[llvm] [DirectX] Legalize memcpy (PR #139173)

[Deric C. via llvm-commits]

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@@ -348,6 +427,7 @@ class DXILLegalizationPipeline {
     LegalizationPipeline.push_back(fixI8UseChain);
     LegalizationPipeline.push_back(downcastI64toI32InsertExtractElements);
     LegalizationPipeline.push_back(legalizeFreeze);
+    LegalizationPipeline.push_back(removeMemCpy);
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Icohedron wrote:

I don't think there is a good reason not to call it "legalizeMemCpy". I just followed what @farzonl did for memset.
I think "legalizeMemCpy" is a better name, so I will make a commit to change it to that.

https://github.com/llvm/llvm-project/pull/139173