[MemCpyOpt] Add test for incorrect memset DSE (NFC)

We can't shorten the memset if there's a throwing call in between
and the destination is non-local.

diff --git a/llvm/test/Transforms/MemCpyOpt/memset-memcpy-redundant-memset.ll b/llvm/test/Transforms/MemCpyOpt/memset-memcpy-redundant-memset.ll
index 758a093..4f9c8be 100644 (file)
--- a/llvm/test/Transforms/MemCpyOpt/memset-memcpy-redundant-memset.ll
+++ b/llvm/test/Transforms/MemCpyOpt/memset-memcpy-redundant-memset.ll
@@ -191,9 +191,46 @@ define void @test_intermediate_write(i8* %b) #0 {
   ret void
 }
 
+define void @test_throwing_call(i8* %src, i64 %src_size, i8* %dst, i64 %dst_size, i8 %c) {
+; CHECK-LABEL: @test_throwing_call(
+; CHECK-NEXT:    call void @call() [[ATTR2:#.*]]
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp ule i64 [[DST_SIZE:%.*]], [[SRC_SIZE:%.*]]
+; CHECK-NEXT:    [[TMP2:%.*]] = sub i64 [[DST_SIZE]], [[SRC_SIZE]]
+; CHECK-NEXT:    [[TMP3:%.*]] = select i1 [[TMP1]], i64 0, i64 [[TMP2]]
+; CHECK-NEXT:    [[TMP4:%.*]] = getelementptr i8, i8* [[DST:%.*]], i64 [[SRC_SIZE]]
+; CHECK-NEXT:    call void @llvm.memset.p0i8.i64(i8* align 1 [[TMP4]], i8 [[C:%.*]], i64 [[TMP3]], i1 false)
+; CHECK-NEXT:    call void @llvm.memcpy.p0i8.p0i8.i64(i8* [[DST]], i8* [[SRC:%.*]], i64 [[SRC_SIZE]], i1 false)
+; CHECK-NEXT:    ret void
+;
+  call void @llvm.memset.p0i8.i64(i8* %dst, i8 %c, i64 %dst_size, i1 false)
+  call void @call() readnone
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst, i8* %src, i64 %src_size, i1 false)
+  ret void
+}
+
+define void @test_throwing_call_alloca(i8* %src, i64 %src_size, i64 %dst_size, i8 %c) {
+; CHECK-LABEL: @test_throwing_call_alloca(
+; CHECK-NEXT:    [[DST:%.*]] = alloca i8, align 1
+; CHECK-NEXT:    call void @call() [[ATTR2]]
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp ule i64 [[DST_SIZE:%.*]], [[SRC_SIZE:%.*]]
+; CHECK-NEXT:    [[TMP2:%.*]] = sub i64 [[DST_SIZE]], [[SRC_SIZE]]
+; CHECK-NEXT:    [[TMP3:%.*]] = select i1 [[TMP1]], i64 0, i64 [[TMP2]]
+; CHECK-NEXT:    [[TMP4:%.*]] = getelementptr i8, i8* [[DST]], i64 [[SRC_SIZE]]
+; CHECK-NEXT:    call void @llvm.memset.p0i8.i64(i8* align 1 [[TMP4]], i8 [[C:%.*]], i64 [[TMP3]], i1 false)
+; CHECK-NEXT:    call void @llvm.memcpy.p0i8.p0i8.i64(i8* [[DST]], i8* [[SRC:%.*]], i64 [[SRC_SIZE]], i1 false)
+; CHECK-NEXT:    ret void
+;
+  %dst = alloca i8
+  call void @llvm.memset.p0i8.i64(i8* %dst, i8 %c, i64 %dst_size, i1 false)
+  call void @call() readnone
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst, i8* %src, i64 %src_size, i1 false)
+  ret void
+}
+
 declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i1)
 declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i1)
 declare void @llvm.memset.p0i8.i32(i8* nocapture, i8, i32, i1)
 declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i1)
 declare void @llvm.memset.p0i8.i128(i8* nocapture, i8, i128, i1)
 declare void @llvm.memcpy.p0i8.p0i8.i128(i8* nocapture, i8* nocapture readonly, i128, i1)
+declare void @call()