MemCpyOpt: When merging memsets also merge the trivial case of two memsets with the same destination.
The testcase is from PR19092, but I think the bug described there is actually a clang issue.
llvm-svn: 203489
diff --git a/llvm/test/Transforms/MemCpyOpt/form-memset.ll b/llvm/test/Transforms/MemCpyOpt/form-memset.ll
index 7c7b4fc..d980b7fd 100644
--- a/llvm/test/Transforms/MemCpyOpt/form-memset.ll
+++ b/llvm/test/Transforms/MemCpyOpt/form-memset.ll
@@ -272,3 +272,15 @@
; CHECK-LABEL: @test9(
; CHECK: call void @llvm.memset.p0i8.i64(i8* bitcast ([16 x i64]* @test9buf to i8*), i8 -1, i64 16, i32 16, i1 false)
}
+
+; PR19092
+define void @test10(i8* nocapture %P) nounwind {
+ tail call void @llvm.memset.p0i8.i64(i8* %P, i8 0, i64 42, i32 1, i1 false)
+ tail call void @llvm.memset.p0i8.i64(i8* %P, i8 0, i64 23, i32 1, i1 false)
+ ret void
+; CHECK-LABEL: @test10(
+; CHECK-NOT: memset
+; CHECK: call void @llvm.memset.p0i8.i64(i8* %P, i8 0, i64 42, i32 1, i1 false)
+; CHECK-NOT: memset
+; CHECK: ret void
+}