Add MSP430 test for PR4136

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71392 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/MSP430/2009-05-10-CyclicDAG.ll b/test/CodeGen/MSP430/2009-05-10-CyclicDAG.ll
new file mode 100644
index 0000000..245c2f9
--- /dev/null
+++ b/test/CodeGen/MSP430/2009-05-10-CyclicDAG.ll
@@ -0,0 +1,32 @@
+; RUN: llvm-as < %s | llc
+; PR4136
+
+target datalayout = "e-p:16:8:8-i8:8:8-i16:8:8-i32:8:8"
+target triple = "msp430-unknown-linux-gnu"
+@uip_len = external global i16		; <i16*> [#uses=2]
+
+define void @uip_arp_arpin() nounwind {
+entry:
+	%tmp = volatile load i16* @uip_len		; <i16> [#uses=1]
+	%cmp = icmp ult i16 %tmp, 42		; <i1> [#uses=1]
+	volatile store i16 0, i16* @uip_len
+	br i1 %cmp, label %if.then, label %if.end
+
+if.then:		; preds = %entry
+	ret void
+
+if.end:		; preds = %entry
+	switch i16 0, label %return [
+		i16 256, label %sw.bb
+		i16 512, label %sw.bb18
+	]
+
+sw.bb:		; preds = %if.end
+	ret void
+
+sw.bb18:		; preds = %if.end
+	ret void
+
+return:		; preds = %if.end
+	ret void
+}