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

[Greg Roth 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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pow2clk wrote:

I know it's just copying the `removeMemSet`, but I think that's a bad description of what this does. It isn't just removing the memcpy, but expanding/legalizing it. Is there a reason not to call this what the change does, "legalizeMemCpy"?

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