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/****************************************************************************** |
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* Top contributors (to current version): |
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* Andrew Reynolds, Gereon Kremer, Aina Niemetz |
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* |
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* This file is part of the cvc5 project. |
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* |
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* Copyright (c) 2009-2021 by the authors listed in the file AUTHORS |
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* in the top-level source directory and their institutional affiliations. |
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* All rights reserved. See the file COPYING in the top-level source |
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* directory for licensing information. |
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* **************************************************************************** |
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* |
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* Implementation of inference to proof conversion. |
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*/ |
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#include "theory/strings/infer_proof_cons.h" |
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#include "expr/proof_node_manager.h" |
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#include "expr/skolem_manager.h" |
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#include "options/smt_options.h" |
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#include "options/strings_options.h" |
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#include "theory/builtin/proof_checker.h" |
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#include "theory/rewriter.h" |
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#include "theory/strings/regexp_operation.h" |
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#include "theory/strings/theory_strings_utils.h" |
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#include "util/statistics_registry.h" |
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using namespace cvc5::kind; |
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namespace cvc5 { |
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namespace theory { |
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namespace strings { |
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1192 |
InferProofCons::InferProofCons(context::Context* c, |
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ProofNodeManager* pnm, |
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1192 |
SequencesStatistics& statistics) |
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1192 |
: d_pnm(pnm), d_lazyFactMap(c), d_statistics(statistics) |
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{ |
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1192 |
Assert(d_pnm != nullptr); |
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1192 |
} |
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|
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1887 |
void InferProofCons::notifyFact(const InferInfo& ii) |
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{ |
44 |
3746 |
Node fact = ii.d_conc; |
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3774 |
Trace("strings-ipc-debug") |
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1887 |
<< "InferProofCons::notifyFact: " << ii << std::endl; |
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1887 |
if (d_lazyFactMap.find(fact) != d_lazyFactMap.end()) |
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{ |
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28 |
Trace("strings-ipc-debug") << "...duplicate!" << std::endl; |
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return; |
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} |
52 |
3718 |
Node symFact = CDProof::getSymmFact(fact); |
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1859 |
if (!symFact.isNull() && d_lazyFactMap.find(symFact) != d_lazyFactMap.end()) |
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{ |
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Trace("strings-ipc-debug") << "...duplicate (sym)!" << std::endl; |
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return; |
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} |
58 |
3718 |
std::shared_ptr<InferInfo> iic = std::make_shared<InferInfo>(ii); |
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1859 |
d_lazyFactMap.insert(ii.d_conc, iic); |
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} |
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1442 |
void InferProofCons::convert(InferenceId infer, |
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bool isRev, |
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Node conc, |
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const std::vector<Node>& exp, |
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ProofStep& ps, |
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TheoryProofStepBuffer& psb, |
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bool& useBuffer) |
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{ |
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// by default, don't use the buffer |
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1442 |
useBuffer = false; |
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// Must flatten children with respect to AND to be ready to explain. |
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// We store the index where each flattened vector begins, since some |
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// explanations are grouped together using AND. |
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2884 |
std::vector<size_t> startExpIndex; |
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4085 |
for (const Node& ec : exp) |
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{ |
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// store the index in the flattened vector |
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2643 |
startExpIndex.push_back(ps.d_children.size()); |
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2643 |
utils::flattenOp(AND, ec, ps.d_children); |
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} |
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// debug print |
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1442 |
if (Trace.isOn("strings-ipc-debug")) |
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{ |
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Trace("strings-ipc-debug") << "InferProofCons::convert: " << infer |
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<< (isRev ? " :rev " : " ") << conc << std::endl; |
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for (const Node& ec : exp) |
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{ |
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Trace("strings-ipc-debug") << " e: " << ec << std::endl; |
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} |
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} |
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// try to find a set of proof steps to incorporate into the buffer |
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1442 |
psb.clear(); |
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1442 |
NodeManager* nm = NodeManager::currentNM(); |
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2884 |
Node nodeIsRev = nm->mkConst(isRev); |
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1442 |
switch (infer) |
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{ |
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// ========================== equal by substitution+rewriting |
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387 |
case InferenceId::STRINGS_I_NORM_S: |
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case InferenceId::STRINGS_I_CONST_MERGE: |
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case InferenceId::STRINGS_I_NORM: |
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case InferenceId::STRINGS_LEN_NORM: |
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case InferenceId::STRINGS_NORMAL_FORM: |
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case InferenceId::STRINGS_CODE_PROXY: |
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{ |
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387 |
ps.d_args.push_back(conc); |
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// will attempt this rule |
108 |
387 |
ps.d_rule = PfRule::MACRO_SR_PRED_INTRO; |
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} |
110 |
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break; |
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// ========================== substitution + rewriting |
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case InferenceId::STRINGS_RE_NF_CONFLICT: |
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case InferenceId::STRINGS_EXTF: |
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case InferenceId::STRINGS_EXTF_N: |
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case InferenceId::STRINGS_EXTF_D: |
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case InferenceId::STRINGS_EXTF_D_N: |
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case InferenceId::STRINGS_I_CONST_CONFLICT: |
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case InferenceId::STRINGS_UNIT_CONST_CONFLICT: |
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{ |
120 |
187 |
if (!ps.d_children.empty()) |
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{ |
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192 |
std::vector<Node> exps(ps.d_children.begin(), ps.d_children.end() - 1); |
123 |
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Node src = ps.d_children[ps.d_children.size() - 1]; |
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96 |
if (psb.applyPredTransform(src, conc, exps)) |
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{ |
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useBuffer = true; |
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} |
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} |
129 |
187 |
if (!useBuffer) |
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{ |
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// use the predicate version? |
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ps.d_args.push_back(conc); |
133 |
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ps.d_rule = PfRule::MACRO_SR_PRED_INTRO; |
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} |
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} |
136 |
187 |
break; |
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// ========================== rewrite pred |
138 |
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case InferenceId::STRINGS_EXTF_EQ_REW: |
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{ |
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// the last child is the predicate we are operating on, move to front |
141 |
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Node src = ps.d_children[ps.d_children.size() - 1]; |
142 |
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std::vector<Node> expe(ps.d_children.begin(), ps.d_children.end() - 1); |
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// start with a default rewrite |
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Node mainEqSRew = psb.applyPredElim(src, expe); |
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if (mainEqSRew == conc) |
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{ |
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useBuffer = true; |
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break; |
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} |
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// may need the "extended equality rewrite" |
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Node mainEqSRew2 = psb.applyPredElim(mainEqSRew, |
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{}, |
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MethodId::SB_DEFAULT, |
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MethodId::SBA_SEQUENTIAL, |
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MethodId::RW_REWRITE_EQ_EXT); |
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if (mainEqSRew2 == conc) |
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{ |
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useBuffer = true; |
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break; |
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} |
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// rewrite again with default rewriter |
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Node mainEqSRew3 = psb.applyPredElim(mainEqSRew2, {}); |
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useBuffer = (mainEqSRew3 == conc); |
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} |
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break; |
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// ========================== substitution+rewriting, CONCAT_EQ, ... |
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case InferenceId::STRINGS_F_CONST: |
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case InferenceId::STRINGS_F_UNIFY: |
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case InferenceId::STRINGS_F_ENDPOINT_EMP: |
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case InferenceId::STRINGS_F_ENDPOINT_EQ: |
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case InferenceId::STRINGS_F_NCTN: |
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case InferenceId::STRINGS_N_EQ_CONF: |
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case InferenceId::STRINGS_N_CONST: |
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case InferenceId::STRINGS_N_UNIFY: |
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case InferenceId::STRINGS_N_ENDPOINT_EMP: |
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case InferenceId::STRINGS_N_ENDPOINT_EQ: |
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case InferenceId::STRINGS_N_NCTN: |
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case InferenceId::STRINGS_SSPLIT_CST_PROP: |
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case InferenceId::STRINGS_SSPLIT_VAR_PROP: |
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case InferenceId::STRINGS_SSPLIT_CST: |
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case InferenceId::STRINGS_SSPLIT_VAR: |
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{ |
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Trace("strings-ipc-core") << "Generate core rule for " << infer |
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<< " (rev=" << isRev << ")" << std::endl; |
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// All of the above inferences have the form: |
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// (explanation for why t and s have the same prefix/suffix) ^ |
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// t = s ^ |
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// (length constraint)? |
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// We call t=s the "main equality" below. The length constraint is |
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// optional, which we split on below. |
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size_t nchild = ps.d_children.size(); |
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size_t mainEqIndex = 0; |
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bool mainEqIndexSet = false; |
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// the length constraint |
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766 |
std::vector<Node> lenConstraint; |
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// these inferences have a length constraint as the last explain |
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if (infer == InferenceId::STRINGS_N_UNIFY || infer == InferenceId::STRINGS_F_UNIFY |
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|| infer == InferenceId::STRINGS_SSPLIT_CST || infer == InferenceId::STRINGS_SSPLIT_VAR |
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|| infer == InferenceId::STRINGS_SSPLIT_VAR_PROP |
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|| infer == InferenceId::STRINGS_SSPLIT_CST_PROP) |
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{ |
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if (exp.size() >= 2) |
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{ |
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Assert(exp.size() <= startExpIndex.size()); |
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// The index of the "main" equality is the last equality before |
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// the length explanation. |
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mainEqIndex = startExpIndex[exp.size() - 1] - 1; |
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mainEqIndexSet = true; |
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// the remainder is the length constraint |
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lenConstraint.insert(lenConstraint.end(), |
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ps.d_children.begin() + mainEqIndex + 1, |
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ps.d_children.end()); |
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} |
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} |
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else if (nchild >= 1) |
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{ |
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// The index of the main equality is the last child. |
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mainEqIndex = nchild - 1; |
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mainEqIndexSet = true; |
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} |
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766 |
Node mainEq; |
222 |
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if (mainEqIndexSet) |
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{ |
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mainEq = ps.d_children[mainEqIndex]; |
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840 |
Trace("strings-ipc-core") << "Main equality " << mainEq << " at index " |
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<< mainEqIndex << std::endl; |
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} |
228 |
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if (mainEq.isNull() || mainEq.getKind() != EQUAL) |
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{ |
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Trace("strings-ipc-core") |
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<< "...failed to find main equality" << std::endl; |
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break; |
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} |
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// apply MACRO_SR_PRED_ELIM using equalities up to the main eq |
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766 |
std::vector<Node> childrenSRew; |
236 |
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childrenSRew.push_back(mainEq); |
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1260 |
childrenSRew.insert(childrenSRew.end(), |
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ps.d_children.begin(), |
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1680 |
ps.d_children.begin() + mainEqIndex); |
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Node mainEqSRew = |
241 |
766 |
psb.tryStep(PfRule::MACRO_SR_PRED_ELIM, childrenSRew, {}); |
242 |
420 |
if (CDProof::isSame(mainEqSRew, mainEq)) |
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{ |
244 |
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Trace("strings-ipc-core") << "...undo step" << std::endl; |
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// the rule added above was not necessary |
246 |
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psb.popStep(); |
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} |
248 |
353 |
else if (mainEqSRew == conc) |
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{ |
250 |
73 |
Trace("strings-ipc-core") << "...success after rewrite!" << std::endl; |
251 |
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useBuffer = true; |
252 |
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break; |
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} |
254 |
694 |
Trace("strings-ipc-core") |
255 |
347 |
<< "Main equality after subs+rewrite " << mainEqSRew << std::endl; |
256 |
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// now, apply CONCAT_EQ to get the remainder |
257 |
693 |
std::vector<Node> childrenCeq; |
258 |
347 |
childrenCeq.push_back(mainEqSRew); |
259 |
693 |
std::vector<Node> argsCeq; |
260 |
347 |
argsCeq.push_back(nodeIsRev); |
261 |
693 |
Node mainEqCeq = psb.tryStep(PfRule::CONCAT_EQ, childrenCeq, argsCeq); |
262 |
694 |
Trace("strings-ipc-core") |
263 |
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<< "Main equality after CONCAT_EQ " << mainEqCeq << std::endl; |
264 |
347 |
if (mainEqCeq.isNull() || mainEqCeq.getKind() != EQUAL) |
265 |
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{ |
266 |
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// fail |
267 |
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break; |
268 |
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} |
269 |
347 |
else if (mainEqCeq == mainEqSRew) |
270 |
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{ |
271 |
91 |
Trace("strings-ipc-core") << "...undo step" << std::endl; |
272 |
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// not necessary, probably first component of equality |
273 |
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psb.popStep(); |
274 |
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} |
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// Now, mainEqCeq is an equality t ++ ... == s ++ ... where the |
276 |
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// inference involved t and s. |
277 |
347 |
if (infer == InferenceId::STRINGS_N_ENDPOINT_EQ |
278 |
260 |
|| infer == InferenceId::STRINGS_N_ENDPOINT_EMP |
279 |
260 |
|| infer == InferenceId::STRINGS_F_ENDPOINT_EQ |
280 |
201 |
|| infer == InferenceId::STRINGS_F_ENDPOINT_EMP) |
281 |
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{ |
282 |
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// Should be equal to conclusion already, or rewrite to it. |
283 |
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// Notice that this step is necessary to handle the "rproc" |
284 |
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// optimization in processSimpleNEq. Alternatively, this could |
285 |
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// possibly be done by CONCAT_EQ with !isRev. |
286 |
292 |
std::vector<Node> cexp; |
287 |
146 |
if (psb.applyPredTransform(mainEqCeq, |
288 |
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conc, |
289 |
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cexp, |
290 |
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MethodId::SB_DEFAULT, |
291 |
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MethodId::SBA_SEQUENTIAL, |
292 |
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MethodId::RW_REWRITE_EQ_EXT)) |
293 |
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{ |
294 |
286 |
Trace("strings-ipc-core") << "Transformed to " << conc |
295 |
143 |
<< " via pred transform" << std::endl; |
296 |
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// success |
297 |
143 |
useBuffer = true; |
298 |
143 |
Trace("strings-ipc-core") << "...success!" << std::endl; |
299 |
146 |
} |
300 |
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// Otherwise, note that EMP rules conclude ti = "" where |
301 |
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// t1 ++ ... ++ tn == "". However, these are very rarely applied, let |
302 |
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// alone for 2+ children. This case is intentionally unhandled here. |
303 |
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} |
304 |
201 |
else if (infer == InferenceId::STRINGS_N_CONST || infer == InferenceId::STRINGS_F_CONST |
305 |
201 |
|| infer == InferenceId::STRINGS_N_EQ_CONF) |
306 |
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{ |
307 |
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// should be a constant conflict |
308 |
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std::vector<Node> childrenC; |
309 |
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childrenC.push_back(mainEqCeq); |
310 |
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std::vector<Node> argsC; |
311 |
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argsC.push_back(nodeIsRev); |
312 |
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Node mainEqC = psb.tryStep(PfRule::CONCAT_CONFLICT, childrenC, argsC); |
313 |
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if (mainEqC == conc) |
314 |
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{ |
315 |
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useBuffer = true; |
316 |
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Trace("strings-ipc-core") << "...success!" << std::endl; |
317 |
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} |
318 |
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} |
319 |
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else |
320 |
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{ |
321 |
401 |
std::vector<Node> tvec; |
322 |
401 |
std::vector<Node> svec; |
323 |
201 |
utils::getConcat(mainEqCeq[0], tvec); |
324 |
201 |
utils::getConcat(mainEqCeq[1], svec); |
325 |
401 |
Node t0 = tvec[isRev ? tvec.size() - 1 : 0]; |
326 |
401 |
Node s0 = svec[isRev ? svec.size() - 1 : 0]; |
327 |
201 |
bool applySym = false; |
328 |
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// may need to apply symmetry |
329 |
402 |
if ((infer == InferenceId::STRINGS_SSPLIT_CST |
330 |
141 |
|| infer == InferenceId::STRINGS_SSPLIT_CST_PROP) |
331 |
261 |
&& t0.isConst()) |
332 |
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{ |
333 |
26 |
Assert(!s0.isConst()); |
334 |
26 |
applySym = true; |
335 |
26 |
std::swap(t0, s0); |
336 |
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} |
337 |
201 |
if (infer == InferenceId::STRINGS_N_UNIFY || infer == InferenceId::STRINGS_F_UNIFY) |
338 |
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{ |
339 |
133 |
if (conc.getKind() != EQUAL) |
340 |
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{ |
341 |
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break; |
342 |
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} |
343 |
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// one side should match, the other side could be a split constant |
344 |
133 |
if (conc[0] != t0 && conc[1] != s0) |
345 |
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{ |
346 |
49 |
applySym = true; |
347 |
49 |
std::swap(t0, s0); |
348 |
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} |
349 |
133 |
Assert(conc[0].isConst() == t0.isConst()); |
350 |
133 |
Assert(conc[1].isConst() == s0.isConst()); |
351 |
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} |
352 |
201 |
PfRule rule = PfRule::UNKNOWN; |
353 |
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// the form of the required length constraint expected by the proof |
354 |
401 |
Node lenReq; |
355 |
201 |
bool lenSuccess = false; |
356 |
201 |
if (infer == InferenceId::STRINGS_N_UNIFY || infer == InferenceId::STRINGS_F_UNIFY) |
357 |
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{ |
358 |
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// the required premise for unify is always len(x) = len(y), |
359 |
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// however the explanation may not be literally this. Thus, we |
360 |
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// need to reconstruct a proof from the given explanation. |
361 |
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// it should be the case that lenConstraint => lenReq. |
362 |
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// We use terms in the conclusion equality, not t0, s0 here. |
363 |
399 |
lenReq = nm->mkNode(STRING_LENGTH, conc[0]) |
364 |
266 |
.eqNode(nm->mkNode(STRING_LENGTH, conc[1])); |
365 |
133 |
lenSuccess = convertLengthPf(lenReq, lenConstraint, psb); |
366 |
133 |
rule = PfRule::CONCAT_UNIFY; |
367 |
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} |
368 |
68 |
else if (infer == InferenceId::STRINGS_SSPLIT_VAR) |
369 |
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{ |
370 |
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// it should be the case that lenConstraint => lenReq |
371 |
3 |
lenReq = nm->mkNode(STRING_LENGTH, t0) |
372 |
2 |
.eqNode(nm->mkNode(STRING_LENGTH, s0)) |
373 |
2 |
.notNode(); |
374 |
1 |
lenSuccess = convertLengthPf(lenReq, lenConstraint, psb); |
375 |
1 |
rule = PfRule::CONCAT_SPLIT; |
376 |
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} |
377 |
67 |
else if (infer == InferenceId::STRINGS_SSPLIT_CST) |
378 |
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{ |
379 |
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// it should be the case that lenConstraint => lenReq |
380 |
180 |
lenReq = nm->mkNode(STRING_LENGTH, t0) |
381 |
120 |
.eqNode(nm->mkConst(Rational(0))) |
382 |
120 |
.notNode(); |
383 |
60 |
lenSuccess = convertLengthPf(lenReq, lenConstraint, psb); |
384 |
60 |
rule = PfRule::CONCAT_CSPLIT; |
385 |
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} |
386 |
7 |
else if (infer == InferenceId::STRINGS_SSPLIT_VAR_PROP) |
387 |
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{ |
388 |
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// it should be the case that lenConstraint => lenReq |
389 |
11 |
for (unsigned r = 0; r < 2; r++) |
390 |
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{ |
391 |
30 |
lenReq = nm->mkNode(GT, |
392 |
20 |
nm->mkNode(STRING_LENGTH, t0), |
393 |
20 |
nm->mkNode(STRING_LENGTH, s0)); |
394 |
10 |
if (convertLengthPf(lenReq, lenConstraint, psb)) |
395 |
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{ |
396 |
6 |
lenSuccess = true; |
397 |
6 |
break; |
398 |
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} |
399 |
4 |
if (r == 0) |
400 |
|
{ |
401 |
|
// may be the other direction |
402 |
3 |
applySym = true; |
403 |
3 |
std::swap(t0, s0); |
404 |
|
} |
405 |
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} |
406 |
7 |
rule = PfRule::CONCAT_LPROP; |
407 |
|
} |
408 |
|
else if (infer == InferenceId::STRINGS_SSPLIT_CST_PROP) |
409 |
|
{ |
410 |
|
// it should be the case that lenConstraint => lenReq |
411 |
|
lenReq = nm->mkNode(STRING_LENGTH, t0) |
412 |
|
.eqNode(nm->mkConst(Rational(0))) |
413 |
|
.notNode(); |
414 |
|
lenSuccess = convertLengthPf(lenReq, lenConstraint, psb); |
415 |
|
rule = PfRule::CONCAT_CPROP; |
416 |
|
} |
417 |
201 |
if (!lenSuccess) |
418 |
|
{ |
419 |
2 |
Trace("strings-ipc-core") |
420 |
1 |
<< "...failed due to length constraint" << std::endl; |
421 |
1 |
break; |
422 |
|
} |
423 |
|
// apply symmetry if necessary |
424 |
200 |
if (applySym) |
425 |
|
{ |
426 |
154 |
std::vector<Node> childrenSymm; |
427 |
77 |
childrenSymm.push_back(mainEqCeq); |
428 |
|
// note this explicit step may not be necessary |
429 |
77 |
mainEqCeq = psb.tryStep(PfRule::SYMM, childrenSymm, {}); |
430 |
154 |
Trace("strings-ipc-core") |
431 |
77 |
<< "Main equality after SYMM " << mainEqCeq << std::endl; |
432 |
|
} |
433 |
200 |
if (rule != PfRule::UNKNOWN) |
434 |
|
{ |
435 |
400 |
Trace("strings-ipc-core") |
436 |
200 |
<< "Core rule length requirement is " << lenReq << std::endl; |
437 |
|
// apply the given rule |
438 |
400 |
std::vector<Node> childrenMain; |
439 |
200 |
childrenMain.push_back(mainEqCeq); |
440 |
200 |
childrenMain.push_back(lenReq); |
441 |
400 |
std::vector<Node> argsMain; |
442 |
200 |
argsMain.push_back(nodeIsRev); |
443 |
400 |
Node mainEqMain = psb.tryStep(rule, childrenMain, argsMain); |
444 |
400 |
Trace("strings-ipc-core") << "Main equality after " << rule << " " |
445 |
200 |
<< mainEqMain << std::endl; |
446 |
200 |
if (mainEqMain == mainEqCeq) |
447 |
|
{ |
448 |
6 |
Trace("strings-ipc-core") << "...undo step" << std::endl; |
449 |
|
// not necessary, probably first component of equality |
450 |
6 |
psb.popStep(); |
451 |
|
} |
452 |
|
// either equal or rewrites to it |
453 |
400 |
std::vector<Node> cexp; |
454 |
200 |
if (psb.applyPredTransform(mainEqMain, conc, cexp)) |
455 |
|
{ |
456 |
|
// requires that length success is also true |
457 |
198 |
useBuffer = true; |
458 |
198 |
Trace("strings-ipc-core") << "...success" << std::endl; |
459 |
|
} |
460 |
|
else |
461 |
|
{ |
462 |
2 |
Trace("strings-ipc-core") << "...fail" << std::endl; |
463 |
|
} |
464 |
|
} |
465 |
|
else |
466 |
|
{ |
467 |
|
// should always have given a rule to try above |
468 |
|
Assert(false) << "No reconstruction rule given for " << infer; |
469 |
|
} |
470 |
346 |
} |
471 |
|
} |
472 |
346 |
break; |
473 |
|
// ========================== Disequalities |
474 |
2 |
case InferenceId::STRINGS_DEQ_DISL_FIRST_CHAR_STRING_SPLIT: |
475 |
|
case InferenceId::STRINGS_DEQ_DISL_STRINGS_SPLIT: |
476 |
|
{ |
477 |
6 |
if (conc.getKind() != AND || conc.getNumChildren() != 2 |
478 |
4 |
|| conc[0].getKind() != EQUAL || !conc[0][0].getType().isStringLike() |
479 |
4 |
|| conc[1].getKind() != EQUAL |
480 |
6 |
|| conc[1][0].getKind() != STRING_LENGTH) |
481 |
|
{ |
482 |
|
Trace("strings-ipc-deq") << "malformed application" << std::endl; |
483 |
|
Assert(false) << "unexpected conclusion " << conc << " for " << infer; |
484 |
|
} |
485 |
|
else |
486 |
|
{ |
487 |
|
Node lenReq = |
488 |
4 |
nm->mkNode(GEQ, nm->mkNode(STRING_LENGTH, conc[0][0]), conc[1][1]); |
489 |
4 |
Trace("strings-ipc-deq") |
490 |
2 |
<< "length requirement is " << lenReq << std::endl; |
491 |
2 |
if (convertLengthPf(lenReq, ps.d_children, psb)) |
492 |
|
{ |
493 |
2 |
Trace("strings-ipc-deq") << "...success length" << std::endl; |
494 |
|
// make the proof |
495 |
4 |
std::vector<Node> childrenMain; |
496 |
2 |
childrenMain.push_back(lenReq); |
497 |
4 |
std::vector<Node> argsMain; |
498 |
2 |
argsMain.push_back(nodeIsRev); |
499 |
|
Node mainConc = |
500 |
4 |
psb.tryStep(PfRule::STRING_DECOMPOSE, childrenMain, argsMain); |
501 |
4 |
Trace("strings-ipc-deq") |
502 |
2 |
<< "...main conclusion is " << mainConc << std::endl; |
503 |
2 |
useBuffer = (mainConc == conc); |
504 |
4 |
Trace("strings-ipc-deq") |
505 |
2 |
<< "...success is " << useBuffer << std::endl; |
506 |
|
} |
507 |
|
else |
508 |
|
{ |
509 |
|
Trace("strings-ipc-deq") << "...fail length" << std::endl; |
510 |
|
} |
511 |
|
} |
512 |
|
} |
513 |
2 |
break; |
514 |
|
// ========================== Boolean split |
515 |
62 |
case InferenceId::STRINGS_CARD_SP: |
516 |
|
case InferenceId::STRINGS_LEN_SPLIT: |
517 |
|
case InferenceId::STRINGS_LEN_SPLIT_EMP: |
518 |
|
case InferenceId::STRINGS_DEQ_DISL_EMP_SPLIT: |
519 |
|
case InferenceId::STRINGS_DEQ_DISL_FIRST_CHAR_EQ_SPLIT: |
520 |
|
case InferenceId::STRINGS_DEQ_STRINGS_EQ: |
521 |
|
case InferenceId::STRINGS_DEQ_LENS_EQ: |
522 |
|
case InferenceId::STRINGS_DEQ_LENGTH_SP: |
523 |
|
{ |
524 |
62 |
if (conc.getKind() != OR) |
525 |
|
{ |
526 |
|
// This should never happen. If it does, we resort to using |
527 |
|
// STRING_TRUST below (in production mode). |
528 |
|
Assert(false) << "Expected OR conclusion for " << infer; |
529 |
|
} |
530 |
|
else |
531 |
|
{ |
532 |
62 |
ps.d_rule = PfRule::SPLIT; |
533 |
62 |
Assert(ps.d_children.empty()); |
534 |
62 |
ps.d_args.push_back(conc[0]); |
535 |
|
} |
536 |
|
} |
537 |
62 |
break; |
538 |
|
// ========================== Regular expression unfolding |
539 |
38 |
case InferenceId::STRINGS_RE_UNFOLD_POS: |
540 |
|
case InferenceId::STRINGS_RE_UNFOLD_NEG: |
541 |
|
{ |
542 |
38 |
Assert (!ps.d_children.empty()); |
543 |
38 |
size_t nchild = ps.d_children.size(); |
544 |
76 |
Node mem = ps.d_children[nchild-1]; |
545 |
38 |
if (nchild>1) |
546 |
|
{ |
547 |
|
// if more than one, apply MACRO_SR_PRED_ELIM |
548 |
|
std::vector<Node> tcs; |
549 |
|
tcs.insert(tcs.end(), |
550 |
|
ps.d_children.begin(), |
551 |
|
ps.d_children.begin() + (nchild-1)); |
552 |
|
mem = psb.applyPredElim(mem, tcs); |
553 |
|
useBuffer = true; |
554 |
|
} |
555 |
38 |
PfRule r = PfRule::UNKNOWN; |
556 |
38 |
if (mem.isNull()) |
557 |
|
{ |
558 |
|
// failed to eliminate above |
559 |
|
Assert(false) << "Failed to apply MACRO_SR_PRED_ELIM for RE unfold"; |
560 |
|
useBuffer = false; |
561 |
|
} |
562 |
38 |
else if (infer == InferenceId::STRINGS_RE_UNFOLD_POS) |
563 |
|
{ |
564 |
30 |
r = PfRule::RE_UNFOLD_POS; |
565 |
|
} |
566 |
|
else |
567 |
|
{ |
568 |
8 |
r = PfRule::RE_UNFOLD_NEG; |
569 |
|
// it may be an optimized form of concat simplification |
570 |
8 |
Assert(mem.getKind() == NOT && mem[0].getKind() == STRING_IN_REGEXP); |
571 |
8 |
if (mem[0][1].getKind() == REGEXP_CONCAT) |
572 |
|
{ |
573 |
|
size_t index; |
574 |
12 |
Node reLen = RegExpOpr::getRegExpConcatFixed(mem[0][1], index); |
575 |
|
// if we can find a fixed length for a component, use the optimized |
576 |
|
// version |
577 |
6 |
if (!reLen.isNull()) |
578 |
|
{ |
579 |
4 |
r = PfRule::RE_UNFOLD_NEG_CONCAT_FIXED; |
580 |
|
} |
581 |
|
} |
582 |
|
} |
583 |
38 |
if (useBuffer) |
584 |
|
{ |
585 |
|
mem = psb.tryStep(r, {mem}, {}); |
586 |
|
// should match the conclusion |
587 |
|
useBuffer = (mem==conc); |
588 |
|
} |
589 |
|
else |
590 |
|
{ |
591 |
38 |
ps.d_rule = r; |
592 |
38 |
} |
593 |
|
} |
594 |
38 |
break; |
595 |
|
// ========================== Reduction |
596 |
81 |
case InferenceId::STRINGS_CTN_POS: |
597 |
|
case InferenceId::STRINGS_CTN_NEG_EQUAL: |
598 |
|
{ |
599 |
81 |
if (ps.d_children.size() != 1) |
600 |
|
{ |
601 |
2 |
break; |
602 |
|
} |
603 |
80 |
bool polarity = ps.d_children[0].getKind() != NOT; |
604 |
160 |
Node atom = polarity ? ps.d_children[0] : ps.d_children[0][0]; |
605 |
160 |
std::vector<Node> args; |
606 |
80 |
args.push_back(atom); |
607 |
160 |
Node res = psb.tryStep(PfRule::STRING_EAGER_REDUCTION, {}, args); |
608 |
80 |
if (res.isNull()) |
609 |
|
{ |
610 |
|
break; |
611 |
|
} |
612 |
|
// ite( contains(x,t), x = k1 ++ t ++ k2, x != t ) |
613 |
160 |
std::vector<Node> tiChildren; |
614 |
80 |
tiChildren.push_back(ps.d_children[0]); |
615 |
|
Node ctnt = psb.tryStep( |
616 |
160 |
polarity ? PfRule::TRUE_INTRO : PfRule::FALSE_INTRO, tiChildren, {}); |
617 |
80 |
if (ctnt.isNull() || ctnt.getKind() != EQUAL) |
618 |
|
{ |
619 |
|
break; |
620 |
|
} |
621 |
160 |
std::vector<Node> tchildren; |
622 |
80 |
tchildren.push_back(ctnt); |
623 |
|
// apply substitution { contains(x,t) -> true|false } and rewrite to get |
624 |
|
// conclusion x = k1 ++ t ++ k2 or x != t. |
625 |
80 |
if (psb.applyPredTransform(res, conc, tchildren)) |
626 |
|
{ |
627 |
80 |
useBuffer = true; |
628 |
81 |
} |
629 |
|
} |
630 |
80 |
break; |
631 |
|
|
632 |
137 |
case InferenceId::STRINGS_REDUCTION: |
633 |
|
{ |
634 |
137 |
size_t nchild = conc.getNumChildren(); |
635 |
274 |
Node mainEq; |
636 |
137 |
if (conc.getKind() == EQUAL) |
637 |
|
{ |
638 |
3 |
mainEq = conc; |
639 |
|
} |
640 |
134 |
else if (conc.getKind() == AND && conc[nchild - 1].getKind() == EQUAL) |
641 |
|
{ |
642 |
134 |
mainEq = conc[nchild - 1]; |
643 |
|
} |
644 |
137 |
if (mainEq.isNull()) |
645 |
|
{ |
646 |
|
Trace("strings-ipc-red") << "Bad Reduction: " << conc << std::endl; |
647 |
|
Assert(false) << "Unexpected reduction " << conc; |
648 |
|
break; |
649 |
|
} |
650 |
274 |
std::vector<Node> argsRed; |
651 |
|
// the left hand side of the last conjunct is the term we are reducing |
652 |
137 |
argsRed.push_back(mainEq[0]); |
653 |
274 |
Node red = psb.tryStep(PfRule::STRING_REDUCTION, {}, argsRed); |
654 |
137 |
Trace("strings-ipc-red") << "Reduction : " << red << std::endl; |
655 |
137 |
if (!red.isNull()) |
656 |
|
{ |
657 |
|
// either equal or rewrites to it |
658 |
274 |
std::vector<Node> cexp; |
659 |
137 |
if (psb.applyPredTransform(red, conc, cexp)) |
660 |
|
{ |
661 |
130 |
Trace("strings-ipc-red") << "...success!" << std::endl; |
662 |
130 |
useBuffer = true; |
663 |
|
} |
664 |
|
else |
665 |
|
{ |
666 |
7 |
Trace("strings-ipc-red") << "...failed to reduce" << std::endl; |
667 |
|
} |
668 |
137 |
} |
669 |
|
} |
670 |
137 |
break; |
671 |
|
// ========================== code injectivity |
672 |
55 |
case InferenceId::STRINGS_CODE_INJ: |
673 |
|
{ |
674 |
55 |
ps.d_rule = PfRule::STRING_CODE_INJ; |
675 |
55 |
Assert(conc.getKind() == OR && conc.getNumChildren() == 3 |
676 |
|
&& conc[2].getKind() == EQUAL); |
677 |
55 |
ps.d_args.push_back(conc[2][0]); |
678 |
55 |
ps.d_args.push_back(conc[2][1]); |
679 |
|
} |
680 |
55 |
break; |
681 |
|
// ========================== unit injectivity |
682 |
10 |
case InferenceId::STRINGS_UNIT_INJ: |
683 |
|
{ |
684 |
10 |
ps.d_rule = PfRule::STRING_SEQ_UNIT_INJ; |
685 |
|
} |
686 |
10 |
break; |
687 |
|
// ========================== prefix conflict |
688 |
32 |
case InferenceId::STRINGS_PREFIX_CONFLICT: |
689 |
|
{ |
690 |
32 |
Trace("strings-ipc-prefix") << "Prefix conflict..." << std::endl; |
691 |
64 |
std::vector<Node> eqs; |
692 |
74 |
for (const Node& e : ps.d_children) |
693 |
|
{ |
694 |
42 |
Kind ek = e.getKind(); |
695 |
42 |
if (ek == EQUAL) |
696 |
|
{ |
697 |
32 |
Trace("strings-ipc-prefix") << "- equality : " << e << std::endl; |
698 |
32 |
eqs.push_back(e); |
699 |
|
} |
700 |
10 |
else if (ek == STRING_IN_REGEXP) |
701 |
|
{ |
702 |
|
// unfold it and extract the equality |
703 |
20 |
std::vector<Node> children; |
704 |
10 |
children.push_back(e); |
705 |
20 |
std::vector<Node> args; |
706 |
20 |
Node eunf = psb.tryStep(PfRule::RE_UNFOLD_POS, children, args); |
707 |
20 |
Trace("strings-ipc-prefix") |
708 |
10 |
<< "--- " << e << " unfolds to " << eunf << std::endl; |
709 |
10 |
if (eunf.isNull()) |
710 |
|
{ |
711 |
|
continue; |
712 |
|
} |
713 |
10 |
else if (eunf.getKind() == AND) |
714 |
|
{ |
715 |
|
// equality is the last conjunct |
716 |
20 |
std::vector<Node> childrenAE; |
717 |
10 |
childrenAE.push_back(eunf); |
718 |
20 |
std::vector<Node> argsAE; |
719 |
10 |
argsAE.push_back(nm->mkConst(Rational(eunf.getNumChildren() - 1))); |
720 |
20 |
Node eunfAE = psb.tryStep(PfRule::AND_ELIM, childrenAE, argsAE); |
721 |
20 |
Trace("strings-ipc-prefix") |
722 |
10 |
<< "--- and elim to " << eunfAE << std::endl; |
723 |
10 |
if (eunfAE.isNull() || eunfAE.getKind() != EQUAL) |
724 |
|
{ |
725 |
|
Assert(false) |
726 |
|
<< "Unexpected unfolded premise " << eunf << " for " << infer; |
727 |
|
continue; |
728 |
|
} |
729 |
20 |
Trace("strings-ipc-prefix") |
730 |
10 |
<< "- equality : " << eunfAE << std::endl; |
731 |
10 |
eqs.push_back(eunfAE); |
732 |
|
} |
733 |
|
else if (eunf.getKind() == EQUAL) |
734 |
|
{ |
735 |
|
Trace("strings-ipc-prefix") << "- equality : " << eunf << std::endl; |
736 |
|
eqs.push_back(eunf); |
737 |
|
} |
738 |
|
} |
739 |
|
else |
740 |
|
{ |
741 |
|
// not sure how to use this assumption |
742 |
|
Assert(false) << "Unexpected premise " << e << " for " << infer; |
743 |
|
} |
744 |
|
} |
745 |
32 |
if (eqs.empty()) |
746 |
|
{ |
747 |
|
break; |
748 |
|
} |
749 |
|
// connect via transitivity |
750 |
64 |
Node curr = eqs[0]; |
751 |
42 |
for (size_t i = 1, esize = eqs.size(); i < esize; i++) |
752 |
|
{ |
753 |
20 |
Node prev = curr; |
754 |
10 |
curr = convertTrans(curr, eqs[1], psb); |
755 |
10 |
if (curr.isNull()) |
756 |
|
{ |
757 |
|
break; |
758 |
|
} |
759 |
10 |
Trace("strings-ipc-prefix") << "- Via trans: " << curr << std::endl; |
760 |
|
} |
761 |
32 |
if (curr.isNull()) |
762 |
|
{ |
763 |
|
break; |
764 |
|
} |
765 |
64 |
Trace("strings-ipc-prefix") |
766 |
32 |
<< "- Possible conflicting equality : " << curr << std::endl; |
767 |
64 |
std::vector<Node> emp; |
768 |
64 |
Node concE = psb.applyPredElim(curr, emp); |
769 |
64 |
Trace("strings-ipc-prefix") |
770 |
32 |
<< "- After pred elim: " << concE << std::endl; |
771 |
32 |
if (concE == conc) |
772 |
|
{ |
773 |
32 |
Trace("strings-ipc-prefix") << "...success!" << std::endl; |
774 |
32 |
useBuffer = true; |
775 |
32 |
} |
776 |
|
} |
777 |
32 |
break; |
778 |
|
// ========================== regular expressions |
779 |
7 |
case InferenceId::STRINGS_RE_INTER_INCLUDE: |
780 |
|
case InferenceId::STRINGS_RE_INTER_CONF: |
781 |
|
case InferenceId::STRINGS_RE_INTER_INFER: |
782 |
|
{ |
783 |
14 |
std::vector<Node> reiExp; |
784 |
14 |
std::vector<Node> reis; |
785 |
14 |
std::vector<Node> reiChildren; |
786 |
14 |
std::vector<Node> reiChildrenOrig; |
787 |
14 |
Node x; |
788 |
|
// make the regular expression intersection that summarizes all |
789 |
|
// memberships in the explanation |
790 |
23 |
for (const Node& c : ps.d_children) |
791 |
|
{ |
792 |
16 |
bool polarity = c.getKind() != NOT; |
793 |
30 |
Node catom = polarity ? c : c[0]; |
794 |
18 |
if (catom.getKind() != STRING_IN_REGEXP) |
795 |
|
{ |
796 |
2 |
Assert(c.getKind() == EQUAL); |
797 |
2 |
if (c.getKind() == EQUAL) |
798 |
|
{ |
799 |
2 |
reiExp.push_back(c); |
800 |
|
} |
801 |
2 |
continue; |
802 |
|
} |
803 |
14 |
if (x.isNull()) |
804 |
|
{ |
805 |
|
// just take the first LHS; others should be equated to it by exp |
806 |
7 |
x = catom[0]; |
807 |
|
} |
808 |
|
Node rcurr = |
809 |
28 |
polarity ? catom[1] : nm->mkNode(REGEXP_COMPLEMENT, catom[1]); |
810 |
14 |
reis.push_back(rcurr); |
811 |
28 |
Node mem = nm->mkNode(STRING_IN_REGEXP, catom[0], rcurr); |
812 |
14 |
reiChildren.push_back(mem); |
813 |
14 |
reiChildrenOrig.push_back(c); |
814 |
|
} |
815 |
|
// go back and justify each premise |
816 |
7 |
bool successChildren = true; |
817 |
21 |
for (size_t i = 0, nchild = reiChildren.size(); i < nchild; i++) |
818 |
|
{ |
819 |
14 |
if (!psb.applyPredTransform(reiChildrenOrig[i], reiChildren[i], reiExp)) |
820 |
|
{ |
821 |
|
Trace("strings-ipc-re") |
822 |
|
<< "... failed to justify child " << reiChildren[i] << " from " |
823 |
|
<< reiChildrenOrig[i] << std::endl; |
824 |
|
successChildren = false; |
825 |
|
break; |
826 |
|
} |
827 |
|
} |
828 |
7 |
if (!successChildren) |
829 |
|
{ |
830 |
|
break; |
831 |
|
} |
832 |
14 |
Node mem = psb.tryStep(PfRule::RE_INTER, reiChildren, {}); |
833 |
14 |
Trace("strings-ipc-re") |
834 |
7 |
<< "Regular expression summary: " << mem << std::endl; |
835 |
|
// the conclusion is rewritable to the premises via rewriting? |
836 |
7 |
if (psb.applyPredTransform(mem, conc, {})) |
837 |
|
{ |
838 |
2 |
Trace("strings-ipc-re") << "... success!" << std::endl; |
839 |
2 |
useBuffer = true; |
840 |
|
} |
841 |
|
else |
842 |
|
{ |
843 |
10 |
Trace("strings-ipc-re") |
844 |
5 |
<< "...failed to rewrite to conclusion" << std::endl; |
845 |
7 |
} |
846 |
|
} |
847 |
7 |
break; |
848 |
|
// ========================== unknown and currently unsupported |
849 |
2 |
case InferenceId::STRINGS_CARDINALITY: |
850 |
|
case InferenceId::STRINGS_I_CYCLE_E: |
851 |
|
case InferenceId::STRINGS_I_CYCLE: |
852 |
|
case InferenceId::STRINGS_INFER_EMP: |
853 |
|
case InferenceId::STRINGS_RE_DELTA: |
854 |
|
case InferenceId::STRINGS_RE_DELTA_CONF: |
855 |
|
case InferenceId::STRINGS_RE_DERIVE: |
856 |
|
case InferenceId::STRINGS_FLOOP: |
857 |
|
case InferenceId::STRINGS_FLOOP_CONFLICT: |
858 |
|
case InferenceId::STRINGS_DEQ_NORM_EMP: |
859 |
|
case InferenceId::STRINGS_CTN_TRANS: |
860 |
|
case InferenceId::STRINGS_CTN_DECOMPOSE: |
861 |
|
default: |
862 |
|
// do nothing, these will be converted to STRING_TRUST below since the |
863 |
|
// rule is unknown. |
864 |
2 |
break; |
865 |
|
} |
866 |
|
|
867 |
|
// now see if we would succeed with the checker-to-try |
868 |
1442 |
bool success = false; |
869 |
1442 |
if (ps.d_rule != PfRule::UNKNOWN) |
870 |
|
{ |
871 |
1350 |
Trace("strings-ipc") << "For " << infer << ", try proof rule " << ps.d_rule |
872 |
675 |
<< "..."; |
873 |
675 |
Assert(ps.d_rule != PfRule::UNKNOWN); |
874 |
1350 |
Node pconc = psb.tryStep(ps.d_rule, ps.d_children, ps.d_args); |
875 |
675 |
if (pconc.isNull() || pconc != conc) |
876 |
|
{ |
877 |
36 |
Trace("strings-ipc") << "failed, pconc is " << pconc << " (expected " |
878 |
18 |
<< conc << ")" << std::endl; |
879 |
18 |
ps.d_rule = PfRule::UNKNOWN; |
880 |
|
} |
881 |
|
else |
882 |
|
{ |
883 |
|
// successfully set up a single step proof in ps |
884 |
657 |
success = true; |
885 |
657 |
Trace("strings-ipc") << "success!" << std::endl; |
886 |
|
} |
887 |
|
} |
888 |
767 |
else if (useBuffer) |
889 |
|
{ |
890 |
|
// successfully set up a multi step proof in psb |
891 |
738 |
success = true; |
892 |
|
} |
893 |
|
else |
894 |
|
{ |
895 |
58 |
Trace("strings-ipc") << "For " << infer << " " << conc |
896 |
29 |
<< ", no proof rule, failed" << std::endl; |
897 |
|
} |
898 |
1442 |
if (!success) |
899 |
|
{ |
900 |
|
// debug print |
901 |
47 |
if (Trace.isOn("strings-ipc-fail")) |
902 |
|
{ |
903 |
|
Trace("strings-ipc-fail") |
904 |
|
<< "InferProofCons::convert: Failed " << infer |
905 |
|
<< (isRev ? " :rev " : " ") << conc << std::endl; |
906 |
|
for (const Node& ec : exp) |
907 |
|
{ |
908 |
|
Trace("strings-ipc-fail") << " e: " << ec << std::endl; |
909 |
|
} |
910 |
|
} |
911 |
|
// untrustworthy conversion, the argument of STRING_TRUST is its conclusion |
912 |
47 |
ps.d_args.clear(); |
913 |
47 |
ps.d_args.push_back(conc); |
914 |
|
// use the trust rule |
915 |
47 |
ps.d_rule = PfRule::STRING_TRUST; |
916 |
|
// add to stats |
917 |
47 |
d_statistics.d_inferencesNoPf << infer; |
918 |
|
} |
919 |
1442 |
if (Trace.isOn("strings-ipc-debug")) |
920 |
|
{ |
921 |
|
if (useBuffer) |
922 |
|
{ |
923 |
|
Trace("strings-ipc-debug") |
924 |
|
<< "InferProofCons::convert returned buffer with " |
925 |
|
<< psb.getNumSteps() << " steps:" << std::endl; |
926 |
|
const std::vector<std::pair<Node, ProofStep>>& steps = psb.getSteps(); |
927 |
|
for (const std::pair<Node, ProofStep>& step : steps) |
928 |
|
{ |
929 |
|
Trace("strings-ipc-debug") |
930 |
|
<< "- " << step.first << " via " << step.second << std::endl; |
931 |
|
} |
932 |
|
} |
933 |
|
else |
934 |
|
{ |
935 |
|
Trace("strings-ipc-debug") |
936 |
|
<< "InferProofCons::convert returned " << ps << std::endl; |
937 |
|
} |
938 |
|
} |
939 |
1442 |
} |
940 |
|
|
941 |
206 |
bool InferProofCons::convertLengthPf(Node lenReq, |
942 |
|
const std::vector<Node>& lenExp, |
943 |
|
TheoryProofStepBuffer& psb) |
944 |
|
{ |
945 |
340 |
for (const Node& le : lenExp) |
946 |
|
{ |
947 |
226 |
if (lenReq == le) |
948 |
|
{ |
949 |
92 |
return true; |
950 |
|
} |
951 |
|
} |
952 |
228 |
Trace("strings-ipc-len") << "Must explain " << lenReq << " by " << lenExp |
953 |
114 |
<< std::endl; |
954 |
126 |
for (const Node& le : lenExp) |
955 |
|
{ |
956 |
|
// probably rewrites to it? |
957 |
134 |
std::vector<Node> exp; |
958 |
122 |
if (psb.applyPredTransform(le, lenReq, exp)) |
959 |
|
{ |
960 |
75 |
Trace("strings-ipc-len") << "...success by rewrite" << std::endl; |
961 |
75 |
return true; |
962 |
|
} |
963 |
|
// maybe x != "" => len(x) != 0 |
964 |
59 |
std::vector<Node> children; |
965 |
47 |
children.push_back(le); |
966 |
59 |
std::vector<Node> args; |
967 |
59 |
Node res = psb.tryStep(PfRule::STRING_LENGTH_NON_EMPTY, children, args); |
968 |
47 |
if (res == lenReq) |
969 |
|
{ |
970 |
35 |
Trace("strings-ipc-len") << "...success by LENGTH_NON_EMPTY" << std::endl; |
971 |
35 |
return true; |
972 |
|
} |
973 |
|
} |
974 |
4 |
Trace("strings-ipc-len") << "...failed" << std::endl; |
975 |
4 |
return false; |
976 |
|
} |
977 |
|
|
978 |
10 |
Node InferProofCons::convertTrans(Node eqa, |
979 |
|
Node eqb, |
980 |
|
TheoryProofStepBuffer& psb) |
981 |
|
{ |
982 |
10 |
if (eqa.getKind() != EQUAL || eqb.getKind() != EQUAL) |
983 |
|
{ |
984 |
|
return Node::null(); |
985 |
|
} |
986 |
10 |
for (uint32_t i = 0; i < 2; i++) |
987 |
|
{ |
988 |
10 |
Node eqaSym = i == 0 ? eqa[1].eqNode(eqa[0]) : eqa; |
989 |
10 |
for (uint32_t j = 0; j < 2; j++) |
990 |
|
{ |
991 |
10 |
Node eqbSym = j == 0 ? eqb : eqb[1].eqNode(eqb[1]); |
992 |
10 |
if (eqa[i] == eqb[j]) |
993 |
|
{ |
994 |
20 |
std::vector<Node> children; |
995 |
10 |
children.push_back(eqaSym); |
996 |
10 |
children.push_back(eqbSym); |
997 |
10 |
return psb.tryStep(PfRule::TRANS, children, {}); |
998 |
|
} |
999 |
|
} |
1000 |
|
} |
1001 |
|
return Node::null(); |
1002 |
|
} |
1003 |
|
|
1004 |
1442 |
std::shared_ptr<ProofNode> InferProofCons::getProofFor(Node fact) |
1005 |
|
{ |
1006 |
|
// temporary proof |
1007 |
2884 |
CDProof pf(d_pnm); |
1008 |
|
// get the inference |
1009 |
1442 |
NodeInferInfoMap::iterator it = d_lazyFactMap.find(fact); |
1010 |
1442 |
if (it == d_lazyFactMap.end()) |
1011 |
|
{ |
1012 |
|
Node factSym = CDProof::getSymmFact(fact); |
1013 |
|
if (!factSym.isNull()) |
1014 |
|
{ |
1015 |
|
// Use the symmetric fact. There is no need to explictly make a |
1016 |
|
// SYMM proof, as this is handled by CDProof::getProofFor below. |
1017 |
|
it = d_lazyFactMap.find(factSym); |
1018 |
|
} |
1019 |
|
} |
1020 |
1442 |
AlwaysAssert(it != d_lazyFactMap.end()); |
1021 |
|
// now go back and convert it to proof steps and add to proof |
1022 |
1442 |
bool useBuffer = false; |
1023 |
2884 |
ProofStep ps; |
1024 |
2884 |
TheoryProofStepBuffer psb(d_pnm->getChecker()); |
1025 |
2884 |
std::shared_ptr<InferInfo> ii = (*it).second; |
1026 |
|
// run the conversion |
1027 |
1442 |
convert(ii->getId(), ii->d_idRev, ii->d_conc, ii->d_premises, ps, psb, useBuffer); |
1028 |
|
// make the proof based on the step or the buffer |
1029 |
1442 |
if (useBuffer) |
1030 |
|
{ |
1031 |
738 |
if (!pf.addSteps(psb)) |
1032 |
|
{ |
1033 |
|
return nullptr; |
1034 |
|
} |
1035 |
|
} |
1036 |
|
else |
1037 |
|
{ |
1038 |
704 |
if (!pf.addStep(fact, ps)) |
1039 |
|
{ |
1040 |
|
return nullptr; |
1041 |
|
} |
1042 |
|
} |
1043 |
1442 |
return pf.getProofFor(fact); |
1044 |
|
} |
1045 |
|
|
1046 |
3292 |
std::string InferProofCons::identify() const |
1047 |
|
{ |
1048 |
3292 |
return "strings::InferProofCons"; |
1049 |
|
} |
1050 |
|
|
1051 |
|
} // namespace strings |
1052 |
|
} // namespace theory |
1053 |
28194 |
} // namespace cvc5 |