[llvm] [RFC] Memory Model Relaxation Annotations (PR #78569)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,106 @@
+//===- MemoryModelRelaxationAnnotations.h -----------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// This file provides utility for Memory Model Relaxation Annotations (MMRAs).
+/// Those annotations are represented using Metadata. The MMRATagSet class
+/// offers a simple API to parse the metadata and perform common operations on
+/// it. The MMRAMetadata class is a simple tuple of MDNode that provides easy
+/// access to all MMRA annotations on an instruction.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_IR_MEMORYMODELRELAXATIONANNOTATIONS_H
+#define LLVM_IR_MEMORYMODELRELAXATIONANNOTATIONS_H
+
+#include <set>
+#include <string>
+#include <tuple>
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nikic wrote:

Doesn't look like tuple is used in this header.

https://github.com/llvm/llvm-project/pull/78569