(proof-new) Split TheoryEngine (#4558)

This PR splits two classes from TheoryEngine (EngineOutputChannel and TheoryPreprocess) that will be undergoing further refactoring for proofs.

This PR does not change their behavior and is code-move only modulo a few cosmetic changes.

1 files changed, 100 insertions, 0 deletions

diff --git a/src/theory/engine_output_channel.h b/src/theory/engine_output_channel.h
new file mode 100644
index 000000000..714a206c2
--- /dev/null
+++ b/src/theory/engine_output_channel.h
@@ -0,0 +1,100 @@
+/*********************                                                        */
+/*! \file engine_output_channel.h
+ ** \verbatim
+ ** Top contributors (to current version):
+ **   Andrew Reynolds
+ ** This file is part of the CVC4 project.
+ ** Copyright (c) 2009-2019 by the authors listed in the file AUTHORS
+ ** in the top-level source directory) and their institutional affiliations.
+ ** All rights reserved.  See the file COPYING in the top-level source
+ ** directory for licensing information.\endverbatim
+ **
+ ** \brief The theory engine output channel.
+ **/
+
+#include "cvc4_private.h"
+
+#ifndef CVC4__THEORY__ENGINE_OUTPUT_CHANNEL_H
+#define CVC4__THEORY__ENGINE_OUTPUT_CHANNEL_H
+
+#include "expr/node.h"
+#include "theory/output_channel.h"
+#include "theory/theory.h"
+#include "util/statistics_registry.h"
+
+namespace CVC4 {
+
+class TheoryEngine;
+
+namespace theory {
+
+/**
+ * An output channel for Theory that passes messages back to a TheoryEngine
+ * for a given Theory.
+ *
+ * Notice that it has interfaces trustedConflict and trustedLemma which are
+ * used for ensuring that proof generators are associated with the lemmas
+ * and conflicts sent on this output channel.
+ */
+class EngineOutputChannel : public theory::OutputChannel
+{
+  friend class TheoryEngine;
+
+ public:
+  EngineOutputChannel(TheoryEngine* engine, theory::TheoryId theory);
+
+  void safePoint(ResourceManager::Resource r) override;
+
+  void conflict(TNode conflictNode,
+                std::unique_ptr<Proof> pf = nullptr) override;
+  bool propagate(TNode literal) override;
+
+  theory::LemmaStatus lemma(TNode lemma,
+                            ProofRule rule,
+                            bool removable = false,
+                            bool preprocess = false,
+                            bool sendAtoms = false) override;
+
+  theory::LemmaStatus splitLemma(TNode lemma, bool removable = false) override;
+
+  void demandRestart() override;
+
+  void requirePhase(TNode n, bool phase) override;
+
+  void setIncomplete() override;
+
+  void spendResource(ResourceManager::Resource r) override;
+
+  void handleUserAttribute(const char* attr, theory::Theory* t) override;
+
+ protected:
+  /**
+   * Statistics for a particular theory.
+   */
+  class Statistics
+  {
+   public:
+    Statistics(theory::TheoryId theory);
+    ~Statistics();
+    /** Number of calls to conflict, propagate, lemma, requirePhase,
+     * restartDemands */
+    IntStat conflicts, propagations, lemmas, requirePhase, restartDemands,
+        trustedConflicts, trustedLemmas;
+  };
+  /** The theory engine we're communicating with. */
+  TheoryEngine* d_engine;
+  /** The statistics of the theory interractions. */
+  Statistics d_statistics;
+  /** The theory owning this channel. */
+  theory::TheoryId d_theory;
+  /** A helper function for registering lemma recipes with the proof engine */
+  void registerLemmaRecipe(Node lemma,
+                           Node originalLemma,
+                           bool preprocess,
+                           theory::TheoryId theoryId);
+};
+
+}  // namespace theory
+}  // namespace CVC4
+
+#endif /* CVC4__THEORY__ENGINE_OUTPUT_CHANNEL_H */