[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"
+#include "clang/Basic/CodeGenOptions.h"
+#include "clang/Basic/Diagnostic.h"
+
+#include "llvm/ADT/IntrusiveRefCntPtr.h"
+#include "llvm/Support/VirtualFileSystem.h"
+
+#include <memory>
+
+namespace mlir {
+class MLIRContext;
+} // namespace mlir
+namespace cir {
+class CIRGenModule;
+
+class CIRGenerator : public clang::ASTConsumer {
+  virtual void anchor();
+  clang::DiagnosticsEngine &Diags;
+  clang::ASTContext *astCtx;
+  llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>
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AaronBallman wrote:

The mixed naming conventions in the header should be fixed (preference is to follow LLVM style if we're changing code around, but if the local preference is for MLIR, that's fine so long as it's consistent).

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