1 files changed, 49 insertions, 0 deletions
diff --git a/llvm/test/Transforms/GVN/callbr-loadpre-critedge.ll b/llvm/test/Transforms/GVN/callbr-loadpre-critedge.ll
new file mode 100644
index 00000000000..2a6a0aa778a
--- /dev/null
+++ b/llvm/test/Transforms/GVN/callbr-loadpre-critedge.ll
@@ -0,0 +1,49 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -gvn -S | FileCheck %s
+
+; This test checks that we don't hang trying to split a critical edge in loadpre
+; when the control flow uses a callbr instruction.
+
+%struct.pluto = type <{ i8, i8 }>
+
+define void @widget(%struct.pluto** %tmp1) {
+; CHECK-LABEL: @widget(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    callbr void asm sideeffect "", "X,X"(i8* blockaddress(@widget, [[BB5:%.*]]), i8* blockaddress(@widget, [[BB8:%.*]]))
+; CHECK-NEXT:    to label [[BB4:%.*]] [label [[BB5]], label %bb8]
+; CHECK:       bb4:
+; CHECK-NEXT:    br label [[BB5]]
+; CHECK:       bb5:
+; CHECK-NEXT:    [[TMP6:%.*]] = load %struct.pluto*, %struct.pluto** [[TMP1:%.*]]
+; CHECK-NEXT:    [[TMP7:%.*]] = getelementptr inbounds [[STRUCT_PLUTO:%.*]], %struct.pluto* [[TMP6]], i64 0, i32 1
+; CHECK-NEXT:    br label [[BB8]]
+; CHECK:       bb8:
+; CHECK-NEXT:    [[TMP9:%.*]] = phi i8* [ [[TMP7]], [[BB5]] ], [ null, [[BB:%.*]] ]
+; CHECK-NEXT:    [[TMP10:%.*]] = load %struct.pluto*, %struct.pluto** [[TMP1]]
+; CHECK-NEXT:    [[TMP11:%.*]] = getelementptr inbounds [[STRUCT_PLUTO]], %struct.pluto* [[TMP10]], i64 0, i32 0
+; CHECK-NEXT:    [[TMP12:%.*]] = load i8, i8* [[TMP11]]
+; CHECK-NEXT:    tail call void @spam(i8* [[TMP9]], i8 [[TMP12]])
+; CHECK-NEXT:    ret void
+;
+bb:
+  callbr void asm sideeffect "", "X,X"(i8* blockaddress(@widget, %bb5), i8* blockaddress(@widget, %bb8))
+  to label %bb4 [label %bb5, label %bb8]
+
+bb4:                                              ; preds = %bb
+  br label %bb5
+
+bb5:                                              ; preds = %bb4, %bb
+  %tmp6 = load %struct.pluto*, %struct.pluto** %tmp1
+  %tmp7 = getelementptr inbounds %struct.pluto, %struct.pluto* %tmp6, i64 0, i32 1
+  br label %bb8
+
+bb8:                                              ; preds = %bb5, %bb
+  %tmp9 = phi i8* [ %tmp7, %bb5 ], [ null, %bb ]
+  %tmp10 = load %struct.pluto*, %struct.pluto** %tmp1
+  %tmp11 = getelementptr inbounds %struct.pluto, %struct.pluto* %tmp10, i64 0, i32 0
+  %tmp12 = load i8, i8* %tmp11
+  tail call void @spam(i8* %tmp9, i8 %tmp12)
+  ret void
+}
+
+declare void @spam(i8*, i8)