[InstCombine] add tests to show potentially bogus application of DeMorgan (NFC)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301714 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Transforms/InstCombine/and-or.ll b/test/Transforms/InstCombine/and-or.ll
index 2ad90ad98e7c252460b68d74e85e780800f2b87d..ce8c7664744fbad8ee845ecbf3314dbcfde365a8 100644 (file)
--- a/test/Transforms/InstCombine/and-or.ll
+++ b/test/Transforms/InstCombine/and-or.ll
@@ -53,3 +53,25 @@ define i32 @func4(i32 %a, i32 %b) {
   ret i32 %tmp3
 }
 
+define i32 @demorganize_constant1(i32 %a) {
+; CHECK-LABEL: @demorganize_constant1(
+; CHECK-NEXT:    [[A_NOT:%.*]] = or i32 %a, -16
+; CHECK-NEXT:    [[AND1:%.*]] = xor i32 [[A_NOT]], 15
+; CHECK-NEXT:    ret i32 [[AND1]]
+;
+  %and = and i32 %a, 15
+  %and1 = xor i32 %and, -1
+  ret i32 %and1
+}
+
+define i32 @demorganize_constant2(i32 %a) {
+; CHECK-LABEL: @demorganize_constant2(
+; CHECK-NEXT:    [[A_NOT:%.*]] = and i32 %a, -16
+; CHECK-NEXT:    [[AND1:%.*]] = xor i32 [[A_NOT]], -16
+; CHECK-NEXT:    ret i32 [[AND1]]
+;
+  %and = or i32 %a, 15
+  %and1 = xor i32 %and, -1
+  ret i32 %and1
+}
+