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

[Bruno Cardoso Lopes via cfe-commits]

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@@ -0,0 +1,61 @@
+//===--- CIRGenModule.h - Per-Module state for CIR gen ----------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This is the internal per-translation-unit state used for CIR translation.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_CIR_CODEGEN_CIRGENMODULE_H
+#define LLVM_CLANG_LIB_CIR_CODEGEN_CIRGENMODULE_H
+
+#include "CIRGenTypeCache.h"
+
+#include "clang/AST/ASTContext.h"
+#include "clang/Basic/CodeGenOptions.h"
+#include "clang/Basic/Diagnostic.h"
+
+#include "mlir/IR/BuiltinOps.h"
+#include "mlir/IR/MLIRContext.h"
+
+using namespace clang;
+namespace cir {
+
+/// This class organizes the cross-function state that is used while generating
+/// CIR code.
+class CIRGenModule : public CIRGenTypeCache {
+  CIRGenModule(CIRGenModule &) = delete;
+  CIRGenModule &operator=(CIRGenModule &) = delete;
+
+public:
+  CIRGenModule(mlir::MLIRContext &context, clang::ASTContext &astctx,
+               const clang::CodeGenOptions &CGO,
+               clang::DiagnosticsEngine &Diags);
+
+  ~CIRGenModule();
+
+private:
+  /// Hold Clang AST information.
+  clang::ASTContext &astCtx;
+
+  const clang::LangOptions &langOpts;
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bcardosolopes wrote:

Agreed, we've been using a mix so we didn't had to go the extra length for something the community could ask us to change as part of upstreaming, so indeed this is the right time to make it happen.

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