[llvm] [CAS] Add OnDiskDataAllocator (PR #161264)

[Steven Wu via llvm-commits]

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@@ -0,0 +1,225 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 Implements OnDiskDataAllocator.
+///
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CAS/OnDiskDataAllocator.h"
+#include "DatabaseFile.h"
+#include "llvm/Config/llvm-config.h"
+
+using namespace llvm;
+using namespace llvm::cas;
+using namespace llvm::cas::ondisk;
+
+OnDiskDataAllocator::OnDiskDataAllocator(OnDiskDataAllocator &&RHS) = default;
+OnDiskDataAllocator &
+OnDiskDataAllocator::operator=(OnDiskDataAllocator &&RHS) = default;
+OnDiskDataAllocator::~OnDiskDataAllocator() = default;
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cachemeifyoucan wrote:

This is due to an abstract type in the class `ImplType` so the constructor needs to be delayed to `.cpp` file.

https://github.com/llvm/llvm-project/pull/161264