Add a new testcase which breaks the sinker because the loop canonnicalization

pass does not do a canonnicalization that the sinker wants.

llvm-svn: 10346

llvm/test/Regression/Transforms/LICM/sink_critical_edge.ll

@@ -0,0 +1,19 @@
+; This testcase checks to make sure the sinker does not cause problems with
+; critical edges.
+
+; RUN: llvm-as < %s | opt -licm | llvm-dis | grep -C1 add | grep Exit
+
+implementation   ; Functions:
+
+void %test() {
+Entry:
+	br bool false, label %Loop, label %Exit
+
+Loop:
+	%X = add int 0, 1
+	br bool false, label %Loop, label %Exit
+
+Exit:
+	%Y = phi int [ 0, %Entry ], [ %X, %Loop ]
+	ret void
+}