[llvm] Reland [CGData] llvm-cgdata #89884 (PR #101461)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,162 @@
+//===- CodeGenDataWriter.cpp ----------------------------------------------===//
+//
+// 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 file contains support for writing codegen data.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGenData/CodeGenDataWriter.h"
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/EndianStream.h"
+
+#define DEBUG_TYPE "cg-data-writer"
+
+using namespace llvm;
+
+namespace llvm {
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MaskRay wrote:

In .cpp files, we don't use `namespace xxx { }` https://llvm.org/docs/CodingStandards.html#use-namespace-qualifiers-to-implement-previously-declared-functions

https://github.com/llvm/llvm-project/pull/101461