Add the testcase from PR8

llvm-svn: 9669
diff --git a/llvm/test/Regression/Transforms/InstCombine/cast-set.ll b/llvm/test/Regression/Transforms/InstCombine/cast-set.ll
index 6ee4cd1..b87c22a 100644
--- a/llvm/test/Regression/Transforms/InstCombine/cast-set.ll
+++ b/llvm/test/Regression/Transforms/InstCombine/cast-set.ll
@@ -47,3 +47,9 @@
 	%C = setne int %B, 0
 	ret bool %C
 }
+
+bool %test7(sbyte* %A) {
+	%B = cast sbyte* %A to int*
+	%C = seteq int* %B, null
+	ret bool %C
+}