[RewriteStatepointsForGC] Add a test exposing an incorrect assertion

diff --git a/llvm/test/Transforms/RewriteStatepointsForGC/phi-vector-bitcast.ll b/llvm/test/Transforms/RewriteStatepointsForGC/phi-vector-bitcast.ll
new file mode 100644 (file)
index 0000000..6f69234
--- /dev/null
+++ b/llvm/test/Transforms/RewriteStatepointsForGC/phi-vector-bitcast.ll
@@ -0,0 +1,28 @@
+; XFAIL: *
+; REQUIRES: asserts
+; RUN: opt < %s -disable-output -passes=rewrite-statepoints-for-gc
+
+; We shouldn't crash when we encounter a vector phi with more than one input
+; from the same predecessor.
+define void @foo(<2 x i8 addrspace(1)*> %arg1, i32 %arg2, i1 %arg3, <2 x i64 addrspace(1)*> %arg4) gc "statepoint-example" personality i32* null {
+bb:
+  %tmp = bitcast <2 x i8 addrspace(1)*> %arg1 to <2 x i64 addrspace(1)*>
+  switch i32 %arg2, label %bb2 [
+    i32 1, label %bb4
+    i32 2, label %bb4
+  ]
+
+bb2:                                              ; preds = %bb
+  br i1 %arg3, label %bb8, label %bb4
+
+bb4:                                              ; preds = %bb2, %bb, %bb
+  %tmp5 = phi <2 x i64 addrspace(1)*> [ %tmp, %bb ], [ %tmp, %bb ], [ %arg4, %bb2 ]
+  call void @bar()
+  %tmp6 = extractelement <2 x i64 addrspace(1)*> %tmp5, i32 1
+  ret void
+
+bb8:                                              ; preds = %bb2
+  ret void
+}
+
+declare void @bar()