[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 +1,107 @@
+//===------ 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"
+
+using llvm::Value;
+using llvm::Function;
+using llvm::AtomicOrdering;
+using clang::SmallVector;
+using clang::CallExpr;
+using clang::QualType;
+using clang::CodeGen::Address;
+using clang::CodeGen::CodeGenFunction;
+
+// Many of MSVC builtins are on x64, ARM and AArch64; to avoid repeating code,
+// we handle them here.
+enum class clang::CodeGen::CodeGenFunction::MSVCIntrin {
+  _BitScanForward,
+  _BitScanReverse,
+  _InterlockedAnd,
+  _InterlockedCompareExchange,
+  _InterlockedDecrement,
+  _InterlockedExchange,
+  _InterlockedExchangeAdd,
+  _InterlockedExchangeSub,
+  _InterlockedIncrement,
+  _InterlockedOr,
+  _InterlockedXor,
+  _InterlockedExchangeAdd_acq,
+  _InterlockedExchangeAdd_rel,
+  _InterlockedExchangeAdd_nf,
+  _InterlockedExchange_acq,
+  _InterlockedExchange_rel,
+  _InterlockedExchange_nf,
+  _InterlockedCompareExchange_acq,
+  _InterlockedCompareExchange_rel,
+  _InterlockedCompareExchange_nf,
+  _InterlockedCompareExchange128,
+  _InterlockedCompareExchange128_acq,
+  _InterlockedCompareExchange128_rel,
+  _InterlockedCompareExchange128_nf,
+  _InterlockedOr_acq,
+  _InterlockedOr_rel,
+  _InterlockedOr_nf,
+  _InterlockedXor_acq,
+  _InterlockedXor_rel,
+  _InterlockedXor_nf,
+  _InterlockedAnd_acq,
+  _InterlockedAnd_rel,
+  _InterlockedAnd_nf,
+  _InterlockedIncrement_acq,
+  _InterlockedIncrement_rel,
+  _InterlockedIncrement_nf,
+  _InterlockedDecrement_acq,
+  _InterlockedDecrement_rel,
+  _InterlockedDecrement_nf,
+  __fastfail,
+};
+
+// Emit a simple intrinsic that has N scalar arguments and a return type
+// matching the argument type. It is assumed that only the first argument is
+// overloaded.
+template <unsigned N>
+Value *emitBuiltinWithOneOverloadedType(CodeGenFunction &CGF,
----------------
s-barannikov wrote:

Sorry if I wasn't clear, I meant *all* declarations should be in a namespace, not only the enum.
And there are still `using` directives that could be avoided if the contents of the file was in `namespace clang::CodeGen { }` (except for `using llvm::xxx`, but I think those types should be referred by fully qualified name to avoid potential collisions with clang's same-named types).

I'm not sure if this suggestion is consistent with clang's style. If it isn't, please let me know.


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