CoroutineStmtBuilder.h

//===- CoroutineStmtBuilder.h - Implicit coroutine stmt builder -*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//===----------------------------------------------------------------------===//
//
//  This file defines CoroutineStmtBuilder, a class for building the implicit
//  statements required for building a coroutine body.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_LIB_SEMA_COROUTINESTMTBUILDER_H
#define LLVM_CLANG_LIB_SEMA_COROUTINESTMTBUILDER_H

#include "clang/AST/Decl.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/StmtCXX.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Sema/SemaInternal.h"

namespace clang {

class CoroutineStmtBuilder : public CoroutineBodyStmt::CtorArgs {
  Sema &S;
  FunctionDecl &FD;
  sema::FunctionScopeInfo &Fn;
  bool IsValid = true;
  SourceLocation Loc;
  SmallVector<Stmt *, 4> ParamMovesVector;
  const bool IsPromiseDependentType;
  CXXRecordDecl *PromiseRecordDecl = nullptr;

public:
  /// \brief Construct a CoroutineStmtBuilder and initialize the promise
  /// statement and initial/final suspends from the FunctionScopeInfo.
  CoroutineStmtBuilder(Sema &S, FunctionDecl &FD, sema::FunctionScopeInfo &Fn,
                       Stmt *Body);

  /// \brief Build the coroutine body statements, including the
  /// "promise dependent" statements when the promise type is not dependent.
  bool buildStatements();

  /// \brief Build the coroutine body statements that require a non-dependent
  /// promise type in order to construct.
  ///
  /// For example different new/delete overloads are selected depending on
  /// if the promise type provides `unhandled_exception()`, and therefore they
  /// cannot be built until the promise type is complete so that we can perform
  /// name lookup.
  bool buildDependentStatements();

  /// \brief Build just parameter moves. To use for rebuilding in TreeTransform.
  bool buildParameterMoves();

  bool isInvalid() const { return !this->IsValid; }

private:
  bool makePromiseStmt();
  bool makeInitialAndFinalSuspend();
  bool makeNewAndDeleteExpr();
  bool makeOnFallthrough();
  bool makeOnException();
  bool makeReturnObject();
  bool makeGroDeclAndReturnStmt();
  bool makeReturnOnAllocFailure();
  bool makeParamMoves();
};

} // end namespace clang

#endif // LLVM_CLANG_LIB_SEMA_COROUTINESTMTBUILDER_H