[llvm] Add the 'initializes' attribute langref and support (PR #84803)

[Arthur Eubanks via llvm-commits]

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@@ -0,0 +1,62 @@
+//===- ConstantRangeListTest.cpp - ConstantRangeList tests ----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/IR/ConstantRangeList.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+namespace {
+
+using ConstantRangeListTest = ::testing::Test;
+
+TEST_F(ConstantRangeListTest, Basics) {
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aeubanks wrote:

can you add a test for (0,4) + (4,8)?

https://github.com/llvm/llvm-project/pull/84803