[llvm] [DirectX] legalize memset (PR #136244)

[Farzon Lotfi via llvm-commits]

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@@ -106,6 +105,7 @@ class DirectXPassConfig : public TargetPassConfig {
     DxilScalarOptions.ScalarizeLoadStore = true;
     addPass(createScalarizerPass(DxilScalarOptions));
     addPass(createDXILLegalizeLegacyPass());
+    addPass(createDXILFinalizeLinkageLegacyPass());
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farzonl wrote:

the legalize legacy pass is a function level pass so it leaves behind the intrinsic decleration in the module. finalize linkage has a cleanup that will remove these dead intrinsics declarations so doing this after legalization works better for cleanup purposes.

https://github.com/llvm/llvm-project/pull/136244