Add some tests for negative constants to unsigned and large positive

constants to signed.

llvm-svn: 32717

test/Feature/testconstants.ll

@@ -24,3 +24,10 @@ begin
 	ret sbyte* null            ; Test null
 end
 
+uint %negativeUnsigned() {
+        ret uint -1
+}
+
+int %largeSigned() {
+       ret int 3900000000
+}