[llvm] [MemCpyOpt] Drop dead `memmove` calls on `memset`'d source data (PR #101930)

[Antonio Frighetto via llvm-commits]

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@@ -51,8 +51,8 @@ define void @destroysrc(ptr %src, ptr %dst) {
 
 define void @destroynoaliassrc(ptr noalias %src, ptr %dst) {
 ; CHECK-LABEL: @destroynoaliassrc(
-; CHECK-NEXT:    call void @llvm.memcpy.p0.p0.i64(ptr align 8 [[DST:%.*]], ptr align 8 [[SRC]], i64 16, i1 false)
-; CHECK-NEXT:    call void @llvm.memset.p0.i64(ptr align 8 [[SRC:%.*]], i8 0, i64 16, i1 false)
+; CHECK-NEXT:    call void @llvm.memcpy.p0.p0.i64(ptr align 8 [[DST:%.*]], ptr align 8 [[SRC:%.*]], i64 16, i1 false)
+; CHECK-NEXT:    call void @llvm.memset.p0.i64(ptr align 8 [[SRC]], i8 0, i64 16, i1 false)
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antoniofrighetto wrote:

Right, it can be landed as a separate change (or I can drop it), if we wish so.

https://github.com/llvm/llvm-project/pull/101930