[llvm] [AArch64] Add AArch64PassRegistry.def (PR #85215)

[Arthur Eubanks via llvm-commits]

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@@ -0,0 +1,45 @@
+//===-- AArch64CodeGenPassBuilder.cpp -----------------------------*- C++ -*-=//
+//
+// 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
+/// This file contains AArch64 CodeGen pipeline builder.
+/// TODO: Port CodeGen passes to new pass manager.
+//===----------------------------------------------------------------------===//
+
+#include "AArch64LoopIdiomTransform.h"
+#include "AArch64TargetMachine.h"
+#include "llvm/Passes/CodeGenPassBuilder.h"
+#include "llvm/Passes/PassBuilder.h"
+
+using namespace llvm;
+
+void AArch64TargetMachine::registerPassBuilderCallbacks(
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aeubanks wrote:

I sort of see what you mean, but I think it's very confusing that one method in a class is defined in a different file than the other methods. I'd be fine with forwarding the actual implementation to a different helper function that's defined in a different file, but the actual `AArch64TargetMachine` method should stay in the original file

https://github.com/llvm/llvm-project/pull/85215