[llvm] [memcpyopt] handle memcpy from memset in more cases (PR #140954)

[Nikita Popov via llvm-commits]

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@@ -73,7 +73,7 @@ define void @test_different_source_gep(ptr %dst1, ptr %dst2, i8 %c) {
 ; CHECK-LABEL: @test_different_source_gep(
 ; CHECK-NEXT:    call void @llvm.memset.p0.i64(ptr [[DST1:%.*]], i8 [[C:%.*]], i64 128, i1 false)
 ; CHECK-NEXT:    [[P:%.*]] = getelementptr i8, ptr [[DST1]], i64 64
-; CHECK-NEXT:    call void @llvm.memcpy.p0.p0.i64(ptr [[DST2:%.*]], ptr [[P]], i64 64, i1 false)
+; CHECK-NEXT:    call void @llvm.memset.p0.i64(ptr [[DST2:%.*]], i8 [[C]], i64 64, i1 false)
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nikic wrote:

Remove the FIXME below.

https://github.com/llvm/llvm-project/pull/140954