Add Thumb-2 tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74295 91177308-0d34-0410-b5e6-96231b3b80d8

test/CodeGen/Thumb2/thumb2-rsb.ll

@@ -0,0 +1,9 @@
+; XFAIL: *
+; this will match as "sub" until we get register shifting
+
+; RUN: llvm-as < %s | llc -march=thumb -mattr=+thumb2 | grep {rsb\\W*r\[0-9\],\\W*r\[0-9\],\\W*r\[0-9\]*} | Count 1
+
+define i32 @f1(i32 %a, i32 %b) {
+    %tmp = sub i32 %b, %a
+    ret i32 %tmp
+}