//===-- include/flang/Parser/parse-state.h ----------------------*- 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 // //===----------------------------------------------------------------------===// #ifndef FORTRAN_PARSER_PARSE_STATE_H_ #define FORTRAN_PARSER_PARSE_STATE_H_ // Defines the ParseState type used as the argument for every parser's // Parse member or static function. Tracks source provenance, context, // accumulated messages, and an arbitrary UserState instance for parsing // attempts. Must be efficient to duplicate and assign for backtracking // and recovery during parsing! #include "user-state.h" #include "flang/Common/Fortran-features.h" #include "flang/Common/idioms.h" #include "flang/Parser/characters.h" #include "flang/Parser/message.h" #include "flang/Parser/provenance.h" #include #include #include #include #include #include namespace Fortran::parser { using common::LanguageFeature; class ParseState { public: ParseState(const CookedSource &cooked) : p_{cooked.AsCharBlock().begin()}, limit_{cooked.AsCharBlock().end()} {} ParseState(const ParseState &that) : p_{that.p_}, limit_{that.limit_}, context_{that.context_}, userState_{that.userState_}, inFixedForm_{that.inFixedForm_}, anyErrorRecovery_{that.anyErrorRecovery_}, anyConformanceViolation_{that.anyConformanceViolation_}, deferMessages_{that.deferMessages_}, anyDeferredMessages_{that.anyDeferredMessages_}, anyTokenMatched_{that.anyTokenMatched_} {} ParseState(ParseState &&that) : p_{that.p_}, limit_{that.limit_}, messages_{std::move(that.messages_)}, context_{std::move(that.context_)}, userState_{that.userState_}, inFixedForm_{that.inFixedForm_}, anyErrorRecovery_{that.anyErrorRecovery_}, anyConformanceViolation_{that.anyConformanceViolation_}, deferMessages_{that.deferMessages_}, anyDeferredMessages_{that.anyDeferredMessages_}, anyTokenMatched_{that.anyTokenMatched_} {} ParseState &operator=(const ParseState &that) { p_ = that.p_, limit_ = that.limit_, context_ = that.context_; userState_ = that.userState_, inFixedForm_ = that.inFixedForm_; anyErrorRecovery_ = that.anyErrorRecovery_; anyConformanceViolation_ = that.anyConformanceViolation_; deferMessages_ = that.deferMessages_; anyDeferredMessages_ = that.anyDeferredMessages_; anyTokenMatched_ = that.anyTokenMatched_; return *this; } ParseState &operator=(ParseState &&that) { p_ = that.p_, limit_ = that.limit_, messages_ = std::move(that.messages_); context_ = std::move(that.context_); userState_ = that.userState_, inFixedForm_ = that.inFixedForm_; anyErrorRecovery_ = that.anyErrorRecovery_; anyConformanceViolation_ = that.anyConformanceViolation_; deferMessages_ = that.deferMessages_; anyDeferredMessages_ = that.anyDeferredMessages_; anyTokenMatched_ = that.anyTokenMatched_; return *this; } const Messages &messages() const { return messages_; } Messages &messages() { return messages_; } const Message::Reference &context() const { return context_; } Message::Reference &context() { return context_; } bool anyErrorRecovery() const { return anyErrorRecovery_; } void set_anyErrorRecovery() { anyErrorRecovery_ = true; } bool anyConformanceViolation() const { return anyConformanceViolation_; } void set_anyConformanceViolation() { anyConformanceViolation_ = true; } UserState *userState() const { return userState_; } ParseState &set_userState(UserState *u) { userState_ = u; return *this; } bool inFixedForm() const { return inFixedForm_; } ParseState &set_inFixedForm(bool yes = true) { inFixedForm_ = yes; return *this; } bool deferMessages() const { return deferMessages_; } ParseState &set_deferMessages(bool yes = true) { deferMessages_ = yes; return *this; } bool anyDeferredMessages() const { return anyDeferredMessages_; } ParseState &set_anyDeferredMessages(bool yes = true) { anyDeferredMessages_ = yes; return *this; } bool anyTokenMatched() const { return anyTokenMatched_; } ParseState &set_anyTokenMatched(bool yes = true) { anyTokenMatched_ = yes; return *this; } const char *GetLocation() const { return p_; } void PushContext(MessageFixedText text) { auto m{new Message{p_, text}}; // reference-counted m->SetContext(context_.get()); context_ = Message::Reference{m}; } void PopContext() { CHECK(context_); context_ = context_->attachment(); } template void Say(CharBlock range, A &&...args) { if (deferMessages_) { anyDeferredMessages_ = true; } else { messages_.Say(range, std::forward(args)...).SetContext(context_.get()); } } template void Say(const MessageFixedText &text, A &&...args) { Say(p_, text, std::forward(args)...); } template void Say(const MessageExpectedText &text, A &&...args) { Say(p_, text, std::forward(args)...); } void Nonstandard(LanguageFeature lf, const MessageFixedText &msg) { Nonstandard(p_, lf, msg); } void Nonstandard( CharBlock range, LanguageFeature lf, const MessageFixedText &msg) { anyConformanceViolation_ = true; if (userState_ && userState_->features().ShouldWarn(lf)) { Say(range, msg); } } bool IsNonstandardOk(LanguageFeature lf, const MessageFixedText &msg) { if (userState_ && !userState_->features().IsEnabled(lf)) { return false; } Nonstandard(lf, msg); return true; } bool IsAtEnd() const { return p_ >= limit_; } const char *UncheckedAdvance(std::size_t n = 1) { const char *result{p_}; p_ += n; return result; } std::optional GetNextChar() { if (p_ < limit_) { return UncheckedAdvance(); } else { return std::nullopt; } } std::optional PeekAtNextChar() const { if (p_ < limit_) { return p_; } else { return std::nullopt; } } std::size_t BytesRemaining() const { std::size_t remain = limit_ - p_; return remain; } void CombineFailedParses(ParseState &&prev) { if (prev.anyTokenMatched_) { if (!anyTokenMatched_ || prev.p_ > p_) { anyTokenMatched_ = true; p_ = prev.p_; messages_ = std::move(prev.messages_); } else if (prev.p_ == p_) { messages_.Merge(std::move(prev.messages_)); } } anyDeferredMessages_ |= prev.anyDeferredMessages_; anyConformanceViolation_ |= prev.anyConformanceViolation_; anyErrorRecovery_ |= prev.anyErrorRecovery_; } private: // Text remaining to be parsed const char *p_{nullptr}, *limit_{nullptr}; // Accumulated messages and current nested context. Messages messages_; Message::Reference context_; UserState *userState_{nullptr}; bool inFixedForm_{false}; bool anyErrorRecovery_{false}; bool anyConformanceViolation_{false}; bool deferMessages_{false}; bool anyDeferredMessages_{false}; bool anyTokenMatched_{false}; // NOTE: Any additions or modifications to these data members must also be // reflected in the copy and move constructors defined at the top of this // class definition! }; } // namespace Fortran::parser #endif // FORTRAN_PARSER_PARSE_STATE_H_