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

[Erich Keane 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;
+
+  [[maybe_unused]] const clang::CodeGenOptions &codeGenOpts;
+
+  /// A "module" matches a c/cpp source file: containing a list of functions.
+  mlir::ModuleOp theModule;
+
+  [[maybe_unused]] clang::DiagnosticsEngine &Diags;
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erichkeane wrote:

Same here, would be nice to only have to bring these in when necessary.

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