+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
+ */
+
+#include "misc/MurmurHash.h"
+#include "support/CPPUtils.h"
+#include "support/Arrays.h"
+
+#include "SemanticContext.h"
+
+using namespace antlr4;
+using namespace antlr4::atn;
+using namespace antlrcpp;
+
+//------------------ Predicate -----------------------------------------------------------------------------------------
+
+SemanticContext::Predicate::Predicate() : Predicate(INVALID_INDEX, INVALID_INDEX, false) {
+}
+
+SemanticContext::Predicate::Predicate(size_t ruleIndex, size_t predIndex, bool isCtxDependent)
+: ruleIndex(ruleIndex), predIndex(predIndex), isCtxDependent(isCtxDependent) {
+}
+
+
+bool SemanticContext::Predicate::eval(Recognizer *parser, RuleContext *parserCallStack) {
+ RuleContext *localctx = nullptr;
+ if (isCtxDependent)
+ localctx = parserCallStack;
+ return parser->sempred(localctx, ruleIndex, predIndex);
+}
+
+size_t SemanticContext::Predicate::hashCode() const {
+ size_t hashCode = misc::MurmurHash::initialize();
+ hashCode = misc::MurmurHash::update(hashCode, ruleIndex);
+ hashCode = misc::MurmurHash::update(hashCode, predIndex);
+ hashCode = misc::MurmurHash::update(hashCode, isCtxDependent ? 1 : 0);
+ hashCode = misc::MurmurHash::finish(hashCode, 3);
+ return hashCode;
+}
+
+bool SemanticContext::Predicate::operator == (const SemanticContext &other) const {
+ if (this == &other)
+ return true;
+
+ const Predicate *p = dynamic_cast<const Predicate*>(&other);
+ if (p == nullptr)
+ return false;
+
+ return ruleIndex == p->ruleIndex && predIndex == p->predIndex && isCtxDependent == p->isCtxDependent;
+}
+
+std::string SemanticContext::Predicate::toString() const {
+ return std::string("{") + std::to_string(ruleIndex) + std::string(":") + std::to_string(predIndex) + std::string("}?");
+}
+
+//------------------ PrecedencePredicate -------------------------------------------------------------------------------
+
+SemanticContext::PrecedencePredicate::PrecedencePredicate() : precedence(0) {
+}
+
+SemanticContext::PrecedencePredicate::PrecedencePredicate(int precedence) : precedence(precedence) {
+}
+
+bool SemanticContext::PrecedencePredicate::eval(Recognizer *parser, RuleContext *parserCallStack) {
+ return parser->precpred(parserCallStack, precedence);
+}
+
+Ref<SemanticContext> SemanticContext::PrecedencePredicate::evalPrecedence(Recognizer *parser,
+ RuleContext *parserCallStack) {
+ if (parser->precpred(parserCallStack, precedence)) {
+ return SemanticContext::NONE;
+ }
+ else {
+ return nullptr;
+ }
+}
+
+int SemanticContext::PrecedencePredicate::compareTo(PrecedencePredicate *o) {
+ return precedence - o->precedence;
+}
+
+size_t SemanticContext::PrecedencePredicate::hashCode() const {
+ size_t hashCode = 1;
+ hashCode = 31 * hashCode + static_cast<size_t>(precedence);
+ return hashCode;
+}
+
+bool SemanticContext::PrecedencePredicate::operator == (const SemanticContext &other) const {
+ if (this == &other)
+ return true;
+
+ const PrecedencePredicate *predicate = dynamic_cast<const PrecedencePredicate *>(&other);
+ if (predicate == nullptr)
+ return false;
+
+ return precedence == predicate->precedence;
+}
+
+std::string SemanticContext::PrecedencePredicate::toString() const {
+ return "{" + std::to_string(precedence) + ">=prec}?";
+}
+
+//------------------ AND -----------------------------------------------------------------------------------------------
+
+SemanticContext::AND::AND(Ref<SemanticContext> const& a, Ref<SemanticContext> const& b) {
+ Set operands;
+
+ if (is<AND>(a)) {
+ for (auto operand : std::dynamic_pointer_cast<AND>(a)->opnds) {
+ operands.insert(operand);
+ }
+ } else {
+ operands.insert(a);
+ }
+
+ if (is<AND>(b)) {
+ for (auto operand : std::dynamic_pointer_cast<AND>(b)->opnds) {
+ operands.insert(operand);
+ }
+ } else {
+ operands.insert(b);
+ }
+
+ std::vector<Ref<PrecedencePredicate>> precedencePredicates = filterPrecedencePredicates(operands);
+
+ if (!precedencePredicates.empty()) {
+ // interested in the transition with the lowest precedence
+ auto predicate = [](Ref<PrecedencePredicate> const& a, Ref<PrecedencePredicate> const& b) {
+ return a->precedence < b->precedence;
+ };
+
+ auto reduced = std::min_element(precedencePredicates.begin(), precedencePredicates.end(), predicate);
+ operands.insert(*reduced);
+ }
+
+ std::copy(operands.begin(), operands.end(), std::back_inserter(opnds));
+}
+
+std::vector<Ref<SemanticContext>> SemanticContext::AND::getOperands() const {
+ return opnds;
+}
+
+bool SemanticContext::AND::operator == (const SemanticContext &other) const {
+ if (this == &other)
+ return true;
+
+ const AND *context = dynamic_cast<const AND *>(&other);
+ if (context == nullptr)
+ return false;
+
+ return Arrays::equals(opnds, context->opnds);
+}
+
+size_t SemanticContext::AND::hashCode() const {
+ return misc::MurmurHash::hashCode(opnds, typeid(AND).hash_code());
+}
+
+bool SemanticContext::AND::eval(Recognizer *parser, RuleContext *parserCallStack) {
+ for (auto opnd : opnds) {
+ if (!opnd->eval(parser, parserCallStack)) {
+ return false;
+ }
+ }
+ return true;
+}
+
+Ref<SemanticContext> SemanticContext::AND::evalPrecedence(Recognizer *parser, RuleContext *parserCallStack) {
+ bool differs = false;
+ std::vector<Ref<SemanticContext>> operands;
+ for (auto context : opnds) {
+ Ref<SemanticContext> evaluated = context->evalPrecedence(parser, parserCallStack);
+ differs |= (evaluated != context);
+ if (evaluated == nullptr) {
+ // The AND context is false if any element is false.
+ return nullptr;
+ } else if (evaluated != NONE) {
+ // Reduce the result by skipping true elements.
+ operands.push_back(evaluated);
+ }
+ }
+
+ if (!differs) {
+ return shared_from_this();
+ }
+
+ if (operands.empty()) {
+ // All elements were true, so the AND context is true.
+ return NONE;
+ }
+
+ Ref<SemanticContext> result = operands[0];
+ for (size_t i = 1; i < operands.size(); ++i) {
+ result = SemanticContext::And(result, operands[i]);
+ }
+
+ return result;
+}
+
+std::string SemanticContext::AND::toString() const {
+ std::string tmp;
+ for (auto var : opnds) {
+ tmp += var->toString() + " && ";
+ }
+ return tmp;
+}
+
+//------------------ OR ------------------------------------------------------------------------------------------------
+
+SemanticContext::OR::OR(Ref<SemanticContext> const& a, Ref<SemanticContext> const& b) {
+ Set operands;
+
+ if (is<OR>(a)) {
+ for (auto operand : std::dynamic_pointer_cast<OR>(a)->opnds) {
+ operands.insert(operand);
+ }
+ } else {
+ operands.insert(a);
+ }
+
+ if (is<OR>(b)) {
+ for (auto operand : std::dynamic_pointer_cast<OR>(b)->opnds) {
+ operands.insert(operand);
+ }
+ } else {
+ operands.insert(b);
+ }
+
+ std::vector<Ref<PrecedencePredicate>> precedencePredicates = filterPrecedencePredicates(operands);
+ if (!precedencePredicates.empty()) {
+ // interested in the transition with the highest precedence
+ auto predicate = [](Ref<PrecedencePredicate> const& a, Ref<PrecedencePredicate> const& b) {
+ return a->precedence < b->precedence;
+ };
+ auto reduced = std::max_element(precedencePredicates.begin(), precedencePredicates.end(), predicate);
+ operands.insert(*reduced);
+ }
+
+ std::copy(operands.begin(), operands.end(), std::back_inserter(opnds));
+}
+
+std::vector<Ref<SemanticContext>> SemanticContext::OR::getOperands() const {
+ return opnds;
+}
+
+bool SemanticContext::OR::operator == (const SemanticContext &other) const {
+ if (this == &other)
+ return true;
+
+ const OR *context = dynamic_cast<const OR *>(&other);
+ if (context == nullptr)
+ return false;
+
+ return Arrays::equals(opnds, context->opnds);
+}
+
+size_t SemanticContext::OR::hashCode() const {
+ return misc::MurmurHash::hashCode(opnds, typeid(OR).hash_code());
+}
+
+bool SemanticContext::OR::eval(Recognizer *parser, RuleContext *parserCallStack) {
+ for (auto opnd : opnds) {
+ if (opnd->eval(parser, parserCallStack)) {
+ return true;
+ }
+ }
+ return false;
+}
+
+Ref<SemanticContext> SemanticContext::OR::evalPrecedence(Recognizer *parser, RuleContext *parserCallStack) {
+ bool differs = false;
+ std::vector<Ref<SemanticContext>> operands;
+ for (auto context : opnds) {
+ Ref<SemanticContext> evaluated = context->evalPrecedence(parser, parserCallStack);
+ differs |= (evaluated != context);
+ if (evaluated == NONE) {
+ // The OR context is true if any element is true.
+ return NONE;
+ } else if (evaluated != nullptr) {
+ // Reduce the result by skipping false elements.
+ operands.push_back(evaluated);
+ }
+ }
+
+ if (!differs) {
+ return shared_from_this();
+ }
+
+ if (operands.empty()) {
+ // All elements were false, so the OR context is false.
+ return nullptr;
+ }
+
+ Ref<SemanticContext> result = operands[0];
+ for (size_t i = 1; i < operands.size(); ++i) {
+ result = SemanticContext::Or(result, operands[i]);
+ }
+
+ return result;
+}
+
+std::string SemanticContext::OR::toString() const {
+ std::string tmp;
+ for(auto var : opnds) {
+ tmp += var->toString() + " || ";
+ }
+ return tmp;
+}
+
+//------------------ SemanticContext -----------------------------------------------------------------------------------
+
+const Ref<SemanticContext> SemanticContext::NONE = std::make_shared<Predicate>(INVALID_INDEX, INVALID_INDEX, false);
+
+SemanticContext::~SemanticContext() {
+}
+
+bool SemanticContext::operator != (const SemanticContext &other) const {
+ return !(*this == other);
+}
+
+Ref<SemanticContext> SemanticContext::evalPrecedence(Recognizer * /*parser*/, RuleContext * /*parserCallStack*/) {
+ return shared_from_this();
+}
+
+Ref<SemanticContext> SemanticContext::And(Ref<SemanticContext> const& a, Ref<SemanticContext> const& b) {
+ if (!a || a == NONE) {
+ return b;
+ }
+
+ if (!b || b == NONE) {
+ return a;
+ }
+
+ Ref<AND> result = std::make_shared<AND>(a, b);
+ if (result->opnds.size() == 1) {
+ return result->opnds[0];
+ }
+
+ return result;
+}
+
+Ref<SemanticContext> SemanticContext::Or(Ref<SemanticContext> const& a, Ref<SemanticContext> const& b) {
+ if (!a) {
+ return b;
+ }
+ if (!b) {
+ return a;
+ }
+
+ if (a == NONE || b == NONE) {
+ return NONE;
+ }
+
+ Ref<OR> result = std::make_shared<OR>(a, b);
+ if (result->opnds.size() == 1) {
+ return result->opnds[0];
+ }
+
+ return result;
+}
+
+std::vector<Ref<SemanticContext::PrecedencePredicate>> SemanticContext::filterPrecedencePredicates(const Set &collection) {
+ std::vector<Ref<SemanticContext::PrecedencePredicate>> result;
+ for (auto context : collection) {
+ if (antlrcpp::is<PrecedencePredicate>(context)) {
+ result.push_back(std::dynamic_pointer_cast<PrecedencePredicate>(context));
+ }
+ }
+
+ return result;
+}
+
+
+//------------------ Operator -----------------------------------------------------------------------------------------
+
+SemanticContext::Operator::~Operator() {
+}
projects / toc / blobdiff