1 files changed, 31 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/xor2.ll b/test/Transforms/InstCombine/xor2.ll
index 89f00bd684..be06d7999d 100644
--- a/test/Transforms/InstCombine/xor2.ll
+++ b/test/Transforms/InstCombine/xor2.ll
@@ -51,3 +51,34 @@ define i32 @test4(i32 %A, i32 %B) {
 ; CHECK: %1 = ashr i32 %A, %B
 ; CHECK: ret i32 %1
 }
+
+; defect-2 in rdar://12329730
+; (X^C1) >> C2) ^ C3 -> (X>>C2) ^ ((C1>>C2)^C3)
+;   where the "X" has more than one use
+define i32 @test5(i32 %val1) {
+test5:
+  %xor = xor i32 %val1, 1234
+  %shr = lshr i32 %xor, 8
+  %xor1 = xor i32 %shr, 1
+  %add = add i32 %xor1, %xor
+  ret i32 %add
+; CHECK: @test5
+; CHECK: lshr i32 %val1, 8
+; CHECK: ret
+}
+
+; defect-1 in rdar://12329730
+; Simplify (X^Y) -> X or Y in the user's context if we know that 
+; only bits from X or Y are demanded.
+; e.g. the "x ^ 1234" can be optimized into x in the context of "t >> 16".
+;  Put in other word, t >> 16 -> x >> 16.
+; unsigned foo(unsigned x) { unsigned t = x ^ 1234; ;  return (t >> 16) + t;}
+define i32 @test6(i32 %x) {
+  %xor = xor i32 %x, 1234
+  %shr = lshr i32 %xor, 16
+  %add = add i32 %shr, %xor
+  ret i32 %add
+; CHECK: @test6
+; CHECK: lshr i32 %x, 16
+; CHECK: ret
+}