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[toc] / antlr4-cpp-runtime-4.9.2-source / runtime / src / atn / ProfilingATNSimulator.h

diff --git a/antlr4-cpp-runtime-4.9.2-source/runtime/src/atn/ProfilingATNSimulator.h b/antlr4-cpp-runtime-4.9.2-source/runtime/src/atn/ProfilingATNSimulator.h
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+/* 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.
+ */
+
+#pragma once
+
+#include "atn/ParserATNSimulator.h"
+#include "atn/DecisionInfo.h"
+
+namespace antlr4 {
+namespace atn {
+
+  class ANTLR4CPP_PUBLIC ProfilingATNSimulator : public ParserATNSimulator {
+  public:
+    ProfilingATNSimulator(Parser *parser);
+
+    virtual size_t adaptivePredict(TokenStream *input, size_t decision, ParserRuleContext *outerContext) override;
+
+    virtual std::vector<DecisionInfo> getDecisionInfo() const;
+    virtual dfa::DFAState* getCurrentState() const;
+
+  protected:
+    std::vector<DecisionInfo> _decisions;
+
+    int _sllStopIndex = 0;
+    int _llStopIndex = 0;
+
+    size_t _currentDecision = 0;
+    dfa::DFAState *_currentState;
+
+    /// <summary>
+    /// At the point of LL failover, we record how SLL would resolve the conflict so that
+    ///  we can determine whether or not a decision / input pair is context-sensitive.
+    ///  If LL gives a different result than SLL's predicted alternative, we have a
+    ///  context sensitivity for sure. The converse is not necessarily true, however.
+    ///  It's possible that after conflict resolution chooses minimum alternatives,
+    ///  SLL could get the same answer as LL. Regardless of whether or not the result indicates
+    ///  an ambiguity, it is not treated as a context sensitivity because LL prediction
+    ///  was not required in order to produce a correct prediction for this decision and input sequence.
+    ///  It may in fact still be a context sensitivity but we don't know by looking at the
+    ///  minimum alternatives for the current input.
+    /// </summary>
+    size_t conflictingAltResolvedBySLL = 0;
+
+    virtual dfa::DFAState* getExistingTargetState(dfa::DFAState *previousD, size_t t) override;
+    virtual dfa::DFAState* computeTargetState(dfa::DFA &dfa, dfa::DFAState *previousD, size_t t) override;
+    virtual std::unique_ptr<ATNConfigSet> computeReachSet(ATNConfigSet *closure, size_t t, bool fullCtx) override;
+    virtual bool evalSemanticContext(Ref<SemanticContext> const& pred, ParserRuleContext *parserCallStack,
+                                     size_t alt, bool fullCtx) override;
+    virtual void reportAttemptingFullContext(dfa::DFA &dfa, const antlrcpp::BitSet &conflictingAlts, ATNConfigSet *configs,
+                                             size_t startIndex, size_t stopIndex) override;
+    virtual void reportContextSensitivity(dfa::DFA &dfa, size_t prediction, ATNConfigSet *configs,
+                                          size_t startIndex, size_t stopIndex) override;
+    virtual void reportAmbiguity(dfa::DFA &dfa, dfa::DFAState *D, size_t startIndex, size_t stopIndex, bool exact,
+                                 const antlrcpp::BitSet &ambigAlts, ATNConfigSet *configs) override;
+  };
+
+} // namespace atn
+} // namespace antlr4