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

[Jonathan Thackray via cfe-commits]

================
@@ -0,0 +1,8530 @@
+//===------ AArch64.cpp - 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This contains code to emit Builtin calls as LLVM code.
+//
+//===----------------------------------------------------------------------===//
+
----------------
jthackray wrote:

Thanks @MacDue. It's about 90% `AArch64` code, and I did briefly look at splitting it, but it's tightly coupled. If it's okay, I'll leave it as-is since I think `AArch64.cpp` better explains the contents. I might try to split it in future, but I've got to merge #132060 before I can land this PR, and I'd like to get this merged soon since it would reduce my compile times.

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