| //===--- IterativeTypeChecker.h - Iterative Type Checker --------*- C++ -*-===// |
| // |
| // This source file is part of the Swift.org open source project |
| // |
| // Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors |
| // Licensed under Apache License v2.0 with Runtime Library Exception |
| // |
| // See https://swift.org/LICENSE.txt for license information |
| // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines the IterativeTypeChecker class, which performs |
| // iterative type checking by tracking the set of outstanding |
| // type-checking requests and servicing them as needed. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef SWIFT_SEMA_ITERATIVE_TYPE_CHECKER_H |
| #define SWIFT_SEMA_ITERATIVE_TYPE_CHECKER_H |
| |
| #include "swift/Sema/TypeCheckRequest.h" |
| #include "swift/AST/DiagnosticEngine.h" |
| #include "swift/Basic/LLVM.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/ADT/STLExtras.h" |
| |
| namespace swift { |
| |
| class ASTContext; |
| class TypeChecker; |
| |
| /// An iterative type checker that processes type check requests to |
| /// ensure that the AST has the information needed by the client. |
| class IterativeTypeChecker { |
| /// The underlying (non-iterative) type checker on which this iterative |
| /// type checker depends. |
| /// |
| /// Each dependency on the non-iterative type checker potentially |
| /// introduces recursion and should be eliminated. |
| TypeChecker &TC; |
| |
| /// A stack of the currently-active requests. |
| SmallVector<TypeCheckRequest, 4> ActiveRequests; |
| |
| // Declare the is<request kind>Satisfied predicates, |
| // enumerateDependenciesOf<request kind> functions, and |
| // satisfy<request kind> functions. |
| #define TYPE_CHECK_REQUEST(Request,PayloadName) \ |
| bool is##Request##Satisfied( \ |
| TypeCheckRequest::PayloadName##PayloadType payload); \ |
| void process##Request( \ |
| TypeCheckRequest::PayloadName##PayloadType payload, \ |
| UnsatisfiedDependency unsatisfiedDependency); \ |
| bool breakCycleFor##Request( \ |
| TypeCheckRequest::PayloadName##PayloadType payload); |
| |
| #include "swift/Sema/TypeCheckRequestKinds.def" |
| |
| void process(TypeCheckRequest request, |
| UnsatisfiedDependency unsatisfiedDependency); |
| |
| /// Attempt to break a cyclic reference for this request after |
| /// diagnosing it. |
| /// |
| /// \returns true if the cycle could be broken by this request, and |
| /// false if it couldn't be broken by altering this request. |
| bool breakCycle(TypeCheckRequest request); |
| |
| /// Diagnose a reference cycle. |
| void diagnoseCircularReference(ArrayRef<TypeCheckRequest> requests); |
| |
| /// Determine whether the given request has already been satisfied. |
| bool isSatisfied(TypeCheckRequest request); |
| |
| public: |
| IterativeTypeChecker(TypeChecker &tc) : TC(tc) { } |
| |
| ASTContext &getASTContext() const; |
| |
| DiagnosticEngine &getDiags() const; |
| |
| template<typename ...ArgTypes> |
| InFlightDiagnostic diagnose(ArgTypes &&...Args) { |
| return getDiags().diagnose(std::forward<ArgTypes>(Args)...); |
| } |
| |
| /// Satisfy the given request. |
| /// |
| /// Ensures that the given type check request has been satisfied. On |
| /// completion of this operation, one can query the AST for |
| /// information regarding this particular request, e.g., get the |
| /// type of a declaration, perform name lookup into a particular |
| /// context, and so on. |
| void satisfy(TypeCheckRequest request); |
| }; |
| |
| } |
| |
| #endif /* SWIFT_SEMA_ITERATIVE_TYPE_CHECKER_H */ |