[clang] [NFC][clang] Split clang/lib/CodeGen/CGBuiltin.cpp into target-specific files (PR #132252)

[Sergei Barannikov via cfe-commits]

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@@ -0,0 +1,105 @@
+//===------ CGBuiltin.h - Emit LLVM Code for builtins ---------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_CODEGEN_CGBUILTIN_H
+#define LLVM_CLANG_LIB_CODEGEN_CGBUILTIN_H
+
+#include "CodeGenFunction.h"
+
+// Many of MSVC builtins are on x64, ARM and AArch64; to avoid repeating code,
+// we handle them here.
+enum class clang::CodeGen::CodeGenFunction::MSVCIntrin {
----------------
s-barannikov wrote:

```suggestion
namespace clang::CodeGen {

enum class CodeGenFunction::MSVCIntrin {
```


https://github.com/llvm/llvm-project/pull/132252