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/********************* */
/*! \file proof_generator.cpp
** \verbatim
** Top contributors (to current version):
** Andrew Reynolds
** This file is part of the CVC4 project.
** Copyright (c) 2009-2020 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 Implementation of proof generator utility
**/
#include "expr/proof_generator.h"
#include "expr/proof.h"
#include "expr/proof_node_algorithm.h"
#include "options/smt_options.h"
namespace CVC4 {
std::ostream& operator<<(std::ostream& out, CDPOverwrite opol)
{
switch (opol)
{
case CDPOverwrite::ALWAYS: out << "ALWAYS"; break;
case CDPOverwrite::ASSUME_ONLY: out << "ASSUME_ONLY"; break;
case CDPOverwrite::NEVER: out << "NEVER"; break;
default: out << "CDPOverwrite:unknown"; break;
}
return out;
}
ProofGenerator::ProofGenerator() {}
ProofGenerator::~ProofGenerator() {}
std::shared_ptr<ProofNode> ProofGenerator::getProofFor(Node f)
{
Unreachable() << "ProofGenerator::getProofFor: " << identify()
<< " has no implementation" << std::endl;
return nullptr;
}
bool ProofGenerator::addProofTo(Node f, CDProof* pf, CDPOverwrite opolicy)
{
Trace("pfgen") << "ProofGenerator::addProofTo: " << f << "..." << std::endl;
Assert(pf != nullptr);
// plug in the proof provided by the generator, if it exists
std::shared_ptr<ProofNode> apf = getProofFor(f);
if (apf != nullptr)
{
Trace("pfgen") << "...got proof " << *apf.get() << std::endl;
// Add the proof, without deep copying.
if (pf->addProof(apf, opolicy, false))
{
Trace("pfgen") << "...success!" << std::endl;
return true;
}
Trace("pfgen") << "...failed to add proof" << std::endl;
}
else
{
Trace("pfgen") << "...failed, no proof" << std::endl;
Assert(false) << "Failed to get proof from generator for fact " << f;
}
return false;
}
/**
* Ensure closed with respect to assumptions, internal version, which
* generalizes the check for a proof generator or a proof node.
*/
void ensureClosedWrtInternal(Node proven,
ProofGenerator* pg,
ProofNode* pnp,
const std::vector<Node>& assumps,
const char* c,
const char* ctx,
bool reqGen)
{
if (!options::proofNew())
{
// proofs not enabled, do not do check
return;
}
bool isTraceDebug = Trace.isOn(c);
if (!options::proofNewEagerChecking() && !isTraceDebug)
{
// trace is off and proof new eager checking is off, do not do check
return;
}
std::stringstream sdiag;
bool isTraceOn = Trace.isOn(c);
if (!isTraceOn)
{
sdiag << ", use -t " << c << " for details";
}
bool dumpProofTraceOn = Trace.isOn("dump-proof-error");
if (!dumpProofTraceOn)
{
sdiag << ", use -t dump-proof-error for details on proof";
}
// get the proof node in question, which is either provided or built by the
// proof generator
std::shared_ptr<ProofNode> pn;
std::stringstream ss;
if (pnp != nullptr)
{
Assert(pg == nullptr);
ss << "ProofNode in context " << ctx;
}
else
{
ss << "ProofGenerator: " << (pg == nullptr ? "null" : pg->identify())
<< " in context " << ctx;
if (pg == nullptr)
{
// only failure if flag is true
if (reqGen)
{
Unreachable() << "...ensureClosed: no generator in context " << ctx
<< sdiag.str();
}
}
else
{
Assert(!proven.isNull());
pn = pg->getProofFor(proven);
pnp = pn.get();
}
}
Trace(c) << "=== ensureClosed: " << ss.str() << std::endl;
Trace(c) << "Proven: " << proven << std::endl;
if (pnp == nullptr)
{
if (pg == nullptr)
{
// did not require generator
Assert(!reqGen);
Trace(c) << "...ensureClosed: no generator in context " << ctx
<< std::endl;
return;
}
}
// if we don't have a proof node, a generator failed
if (pnp == nullptr)
{
Assert(pg != nullptr);
AlwaysAssert(false) << "...ensureClosed: null proof from " << ss.str()
<< sdiag.str();
}
std::vector<Node> fassumps;
expr::getFreeAssumptions(pnp, fassumps);
bool isClosed = true;
std::stringstream ssf;
for (const Node& fa : fassumps)
{
if (std::find(assumps.begin(), assumps.end(), fa) == assumps.end())
{
isClosed = false;
ssf << "- " << fa << std::endl;
}
}
if (!isClosed)
{
Trace(c) << "Free assumptions:" << std::endl;
Trace(c) << ssf.str();
if (!assumps.empty())
{
Trace(c) << "Expected assumptions:" << std::endl;
for (const Node& a : assumps)
{
Trace(c) << "- " << a << std::endl;
}
}
if (dumpProofTraceOn)
{
Trace("dump-proof-error") << " Proof: " << *pnp << std::endl;
}
}
AlwaysAssert(isClosed) << "...ensureClosed: open proof from " << ss.str()
<< sdiag.str();
Trace(c) << "...ensureClosed: success" << std::endl;
Trace(c) << "====" << std::endl;
}
void pfgEnsureClosed(Node proven,
ProofGenerator* pg,
const char* c,
const char* ctx,
bool reqGen)
{
Assert(!proven.isNull());
// proof generator may be null
std::vector<Node> assumps;
ensureClosedWrtInternal(proven, pg, nullptr, assumps, c, ctx, reqGen);
}
void pfgEnsureClosedWrt(Node proven,
ProofGenerator* pg,
const std::vector<Node>& assumps,
const char* c,
const char* ctx,
bool reqGen)
{
Assert(!proven.isNull());
// proof generator may be null
ensureClosedWrtInternal(proven, pg, nullptr, assumps, c, ctx, reqGen);
}
void pfnEnsureClosed(ProofNode* pn, const char* c, const char* ctx)
{
ensureClosedWrtInternal(Node::null(), nullptr, pn, {}, c, ctx, false);
}
void pfnEnsureClosedWrt(ProofNode* pn,
const std::vector<Node>& assumps,
const char* c,
const char* ctx)
{
ensureClosedWrtInternal(Node::null(), nullptr, pn, assumps, c, ctx, false);
}
} // namespace CVC4
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