[llvm] [ConstantRange] Add binaryOp supporting 'or disjoint'. (PR #222573)

[Nikita Popov via llvm-commits]

================
@@ -2969,6 +2969,33 @@ TEST_F(ConstantRangeTest, binaryOr) {
       CheckSingleElementsOnly);
 }
 
+TEST_F(ConstantRangeTest, binaryOpDisjointOr) {
+  // TestBinaryOpExhaustive enumerates 1- and 4-bit ranges, create or disjoint
+  // binary ops up front for the bitwidths.
+  LLVMContext Ctx;
+  std::unique_ptr<BinaryOperator> DisjointOr[2];
+  for (auto [Idx, Bits] : enumerate(ArrayRef<unsigned>({1, 4}))) {
+    Value *Poison = PoisonValue::get(Type::getIntNTy(Ctx, Bits));
+    DisjointOr[Idx].reset(
+        BinaryOperator::CreateDisjoint(Instruction::Or, Poison, Poison));
+  }
+
+  TestBinaryOpExhaustive(
+      [&](const ConstantRange &CR1, const ConstantRange &CR2) {
+        const BinaryOperator &BO = *DisjointOr[CR1.getBitWidth() == 1 ? 0 : 1];
+        return CR1.binaryOp(BO, CR2);
+      },
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
+        if (N1.intersects(N2))
+          return std::nullopt;
+        return N1 | N2;
+      },
+      PreferSmallest,
+      [](const ConstantRange &, const ConstantRange &) {
+        return false; // Check correctness only.
+      });
+}
----------------
nikic wrote:

As you are not testing optimality, it would be good to include some tests for specific cases here. (Mainly enough to show that all of nuw, nsw and or provide some value here.)

https://github.com/llvm/llvm-project/pull/222573