[llvm] [CGData] Outlined Hash Tree (PR #89792)

[Ellis Hoag via llvm-commits]

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@@ -0,0 +1,67 @@
+//===- OutlinedHashTreeRecord.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
+//
+//===---------------------------------------------------------------------===//
+//
+// This defines the OutlinedHashTreeRecord class. This class holds the outlined
+// hash tree for both serialization and deserialization processes. It utilizes
+// two data formats for serialization: raw binary data and YAML.
+// These two formats can be used interchangeably.
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGENDATA_OUTLINEDHASHTREERECORD_H
+#define LLVM_CODEGENDATA_OUTLINEDHASHTREERECORD_H
+
+#include "llvm/CodeGenData/OutlinedHashTree.h"
+
+namespace llvm {
+
+using IdHashNodeStableMapTy = std::map<unsigned, HashNodeStable>;
+using IdHashNodeMapTy = std::map<unsigned, HashNode *>;
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ellishg wrote:

Can we use `DenseMap` here?

https://github.com/llvm/llvm-project/pull/89792