[clang] [CIR] Build out AST consumer patterns to reach the entry point into CIRGen (PR #91007)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,59 @@
+//===- CIRGenerator.h - CIR Generation from Clang AST ---------------------===//
+//
+// 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 declares a simple interface to perform CIR generation from Clang
+// AST
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CLANG_CIRGENERATOR_H_
+#define CLANG_CIRGENERATOR_H_
+
+#include "clang/AST/ASTConsumer.h"
+#include "clang/AST/DeclGroup.h"
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AaronBallman wrote:

This can be replaced with a forward declare.

https://github.com/llvm/llvm-project/pull/91007