mirror of
https://github.com/ethereum/solidity
synced 2023-10-03 13:03:40 +00:00
Reasoning based simplifier.
This commit is contained in:
parent
d7106287e8
commit
e47023a222
@ -45,7 +45,7 @@ struct OptimiserSettings
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"dhfoDgvulfnTUtnIf" // None of these can make stack problems worse
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"["
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"xa[r]EscLM" // Turn into SSA and simplify
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"cCTUtTOntnfDIul" // Perform structural simplification
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"RcCTUtTOntnfDIul" // Perform structural simplification
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"Lcul" // Simplify again
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"Vcul [j]" // Reverse SSA
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@ -247,9 +247,9 @@ void BooleanLPSolver::addAssertion(Expression const& _expr)
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pair<CheckResult, vector<string>> BooleanLPSolver::check(vector<Expression> const& _expressionsToEvaluate)
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{
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// cout << "Solving boolean constraint system" << endl;
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// cout << toString() << endl;
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// cout << "--------------" << endl;
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cout << "Solving boolean constraint system" << endl;
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cout << toString() << endl;
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cout << "--------------" << endl;
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if (m_state.back().infeasible)
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return make_pair(CheckResult::UNSATISFIABLE, vector<string>{});
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@ -22,11 +22,14 @@
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#include <libyul/optimiser/Semantics.h>
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#include <libyul/AST.h>
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#include <libyul/Dialect.h>
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#include <libyul/Utilities.h>
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#include <libsmtutil/SMTPortfolio.h>
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#include <libsmtutil/Helpers.h>
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#include <libsolutil/CommonData.h>
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#include <libsolutil/BooleanLP.h>
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#include <libsolutil/Visitor.h>
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#include <utility>
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#include <memory>
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@ -43,31 +46,83 @@ void ReasoningBasedSimplifier::run(OptimiserStepContext& _context, Block& _ast)
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ReasoningBasedSimplifier{_context.dialect, ssaVars}(_ast);
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}
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std::optional<string> ReasoningBasedSimplifier::invalidInCurrentEnvironment()
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{
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// SMTLib2 interface is always available, but we would like to have synchronous answers.
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if (smtutil::SMTPortfolio{}.solvers() <= 1)
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return string{"No SMT solvers available."};
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else
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return nullopt;
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}
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void ReasoningBasedSimplifier::operator()(VariableDeclaration& _varDecl)
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{
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SMTSolver::encodeVariableDeclaration(_varDecl);
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if (_varDecl.variables.size() != 1 || !_varDecl.value)
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return;
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YulString varName = _varDecl.variables.front().name;
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if (!m_ssaVariables.count(varName))
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return;
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// TODO for a boolean variable, we could check if it is
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// a constant.
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smtutil::Expression variable = newRestrictedVariable(
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"yul_" + varName.str(),
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_varDecl.value && isBoolean(*_varDecl.value)
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);
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bool const inserted = m_variables.insert({varName, variable}).second;
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yulAssert(inserted, "");
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if (!_varDecl.value)
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return; // TODO we could encode zero, but the variable should not be used anyway.
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std::visit(GenericVisitor{
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[&](FunctionCall const& _functionCall)
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{
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if (auto const* dialect = dynamic_cast<EVMDialect const*>(&m_dialect))
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if (auto const* builtin = dialect->builtin(_functionCall.functionName.name))
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if (builtin->instruction)
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handleDeclaration(varName, *builtin->instruction, _functionCall.arguments);
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},
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[&](Identifier const& _identifier)
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{
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if (
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m_ssaVariables.count(_identifier.name) &&
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m_variables.count(_identifier.name)
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)
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m_solver->addAssertion(variable == m_variables.at(_identifier.name));
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},
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[&](Literal const& _literal)
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{
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// TODO could avoid encoding the restrictions.
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m_solver->addAssertion(variable == literalValue(_literal));
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}
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}, *_varDecl.value);
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if (_varDecl.value && isBoolean(*_varDecl.value) && SideEffectsCollector{m_dialect, *_varDecl.value}.movable())
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{
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// TODO if we use this, then it actually already handles the if statement case...
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if (makesInfeasible(!variable))
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// TODO debug data
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_varDecl.value = make_unique<yul::Expression>(m_dialect.trueLiteral());
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else if (makesInfeasible(variable))
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_varDecl.value = make_unique<yul::Expression>(m_dialect.zeroLiteralForType({}));
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}
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// TODO could use SMTSolver::encodeVariableDeclaration(_varDecl);
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}
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void ReasoningBasedSimplifier::operator()(If& _if)
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{
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if (!SideEffectsCollector{m_dialect, *_if.condition}.movable())
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if (!holds_alternative<Identifier>(*_if.condition))
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{
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ASTModifier::operator()(_if.body);
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return;
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}
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Identifier const& condition = get<Identifier>(*_if.condition);
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if (!m_ssaVariables.count(condition.name) || !m_variables.count(condition.name))
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{
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ASTModifier::operator()(_if.body);
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return;
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}
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smtutil::Expression cond = m_variables.at(condition.name);
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smtutil::Expression condition = encodeExpression(*_if.condition);
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m_solver->push();
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m_solver->addAssertion(condition == constantValue(0));
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CheckResult result = m_solver->check({}).first;
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m_solver->pop();
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if (result == CheckResult::UNSATISFIABLE)
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bool constantTrue = makesInfeasible(
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isBoolean(*_if.condition) ?
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!cond :
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(cond == bigint(0))
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);
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if (constantTrue)
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{
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Literal trueCondition = m_dialect.trueLiteral();
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trueCondition.debugData = debugDataOf(*_if.condition);
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@ -75,11 +130,13 @@ void ReasoningBasedSimplifier::operator()(If& _if)
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}
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else
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{
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m_solver->push();
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m_solver->addAssertion(condition != constantValue(0));
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CheckResult result2 = m_solver->check({}).first;
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m_solver->pop();
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if (result2 == CheckResult::UNSATISFIABLE)
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bool constantFalse = makesInfeasible(
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isBoolean(*_if.condition) ?
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cond :
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(cond >= bigint(1))
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);
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if (constantFalse)
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{
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Literal falseCondition = m_dialect.zeroLiteralForType(m_dialect.boolType);
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falseCondition.debugData = debugDataOf(*_if.condition);
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@ -91,10 +148,61 @@ void ReasoningBasedSimplifier::operator()(If& _if)
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}
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m_solver->push();
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m_solver->addAssertion(condition != constantValue(0));
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if (isBoolean(*_if.condition))
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m_solver->addAssertion(cond);
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else
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m_solver->addAssertion(cond >= bigint(1));
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ASTModifier::operator()(_if.body);
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m_solver->pop();
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// TODO if we do this, we have to push/pop inside for loops because
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// 'leave' / 'continue' is considered terminating.
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bool bodyTerminates =
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!_if.body.statements.empty() &&
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TerminationFinder(m_dialect).controlFlowKind(_if.body.statements.back()) !=
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TerminationFinder::ControlFlow::FlowOut;
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if (bodyTerminates)
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{
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cout << "Body always terminates." << endl;
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if (isBoolean(*_if.condition))
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m_solver->addAssertion(!cond);
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else
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m_solver->addAssertion(cond == bigint(0));
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}
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}
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// TODO switch also needs push/pop?
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// TODO does break/continue need pecial handling in loops?
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// TODO leave in functions?
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void ReasoningBasedSimplifier::operator()(ForLoop& _for)
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{
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(*this)(_for.pre);
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visit(*_for.condition);
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m_solver->push();
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Identifier const* condition = get_if<Identifier>(_for.condition.get());
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if (condition && m_ssaVariables.count(condition->name) && m_variables.count(condition->name))
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{
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smtutil::Expression cond = m_variables.at(condition->name);
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if (isBoolean(*_for.condition))
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m_solver->addAssertion(cond);
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else
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m_solver->addAssertion(cond >= bigint(1));
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}
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(*this)(_for.body);
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(*this)(_for.post);
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m_solver->pop();
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}
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void ReasoningBasedSimplifier::operator()(FunctionDefinition& _fun)
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{
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m_solver->push();
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ASTModifier::operator()(_fun);
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m_solver->pop();
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}
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@ -102,125 +210,202 @@ ReasoningBasedSimplifier::ReasoningBasedSimplifier(
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Dialect const& _dialect,
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set<YulString> const& _ssaVariables
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):
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SMTSolver(_ssaVariables, _dialect),
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m_dialect(_dialect)
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m_dialect(_dialect),
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m_ssaVariables(_ssaVariables),
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m_solver(make_unique<util::BooleanLPSolver>())
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{
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}
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smtutil::Expression ReasoningBasedSimplifier::encodeEVMBuiltin(
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void ReasoningBasedSimplifier::handleDeclaration(
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YulString _varName,
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evmasm::Instruction _instruction,
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vector<yul::Expression> const& _arguments
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)
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{
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vector<smtutil::Expression> arguments = applyMap(
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_arguments,
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[this](yul::Expression const& _expr) { return encodeExpression(_expr); }
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);
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smtutil::Expression variable = m_variables.at(_varName);
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vector<smtutil::Expression> arguments;
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for (yul::Expression const& arg: _arguments)
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{
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if (holds_alternative<Identifier>(arg))
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{
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Identifier const& v = get<Identifier>(arg);
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if (!m_ssaVariables.count(v.name) || !m_variables.count(v.name))
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return;
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arguments.push_back(m_variables.at(v.name));
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}
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else if (holds_alternative<Literal>(arg))
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arguments.push_back(literalValue(get<Literal>(arg)));
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else
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return;
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}
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optional<smtutil::Expression> x;
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optional<smtutil::Expression> y;
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optional<smtutil::Expression> z;
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if (arguments.size() > 0)
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x = arguments.at(0);
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if (arguments.size() > 1)
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y = arguments.at(1);
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if (arguments.size() > 2)
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z = arguments.at(2);
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switch (_instruction)
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{
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case evmasm::Instruction::ADD:
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return wrap(arguments.at(0) + arguments.at(1));
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case evmasm::Instruction::MUL:
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return wrap(arguments.at(0) * arguments.at(1));
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{
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smtutil::Expression overflow = m_solver->newVariable(uniqueName(), SortProvider::boolSort);
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m_solver->addAssertion(overflow || (variable == *x + *y));
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m_solver->addAssertion(!overflow || (variable == *x + *y - smtutil::Expression(bigint(1) << 256)));
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break;
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}
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case evmasm::Instruction::SUB:
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return wrap(arguments.at(0) - arguments.at(1));
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case evmasm::Instruction::DIV:
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return smtutil::Expression::ite(
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arguments.at(1) == constantValue(0),
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constantValue(0),
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arguments.at(0) / arguments.at(1)
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);
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case evmasm::Instruction::SDIV:
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return smtutil::Expression::ite(
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arguments.at(1) == constantValue(0),
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constantValue(0),
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// No `wrap()` needed here, because -2**255 / -1 results
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// in 2**255 which is "converted" to its two's complement
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// representation 2**255 in `signedToTwosComplement`
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signedToTwosComplement(smtutil::signedDivisionEVM(
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twosComplementToSigned(arguments.at(0)),
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twosComplementToSigned(arguments.at(1))
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))
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);
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case evmasm::Instruction::MOD:
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return smtutil::Expression::ite(
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arguments.at(1) == constantValue(0),
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constantValue(0),
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arguments.at(0) % arguments.at(1)
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);
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case evmasm::Instruction::SMOD:
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return smtutil::Expression::ite(
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arguments.at(1) == constantValue(0),
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constantValue(0),
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signedToTwosComplement(signedModuloEVM(
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twosComplementToSigned(arguments.at(0)),
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twosComplementToSigned(arguments.at(1))
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))
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);
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case evmasm::Instruction::LT:
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return booleanValue(arguments.at(0) < arguments.at(1));
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case evmasm::Instruction::SLT:
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return booleanValue(twosComplementToSigned(arguments.at(0)) < twosComplementToSigned(arguments.at(1)));
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case evmasm::Instruction::GT:
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return booleanValue(arguments.at(0) > arguments.at(1));
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case evmasm::Instruction::SGT:
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return booleanValue(twosComplementToSigned(arguments.at(0)) > twosComplementToSigned(arguments.at(1)));
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case evmasm::Instruction::EQ:
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return booleanValue(arguments.at(0) == arguments.at(1));
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case evmasm::Instruction::ISZERO:
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return booleanValue(arguments.at(0) == constantValue(0));
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case evmasm::Instruction::AND:
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return smtutil::Expression::ite(
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(arguments.at(0) == 0 || arguments.at(0) == 1) &&
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(arguments.at(1) == 0 || arguments.at(1) == 1),
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booleanValue(arguments.at(0) == 1 && arguments.at(1) == 1),
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bv2int(int2bv(arguments.at(0)) & int2bv(arguments.at(1)))
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);
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case evmasm::Instruction::OR:
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return smtutil::Expression::ite(
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(arguments.at(0) == 0 || arguments.at(0) == 1) &&
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(arguments.at(1) == 0 || arguments.at(1) == 1),
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booleanValue(arguments.at(0) == 1 || arguments.at(1) == 1),
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bv2int(int2bv(arguments.at(0)) | int2bv(arguments.at(1)))
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);
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case evmasm::Instruction::XOR:
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return bv2int(int2bv(arguments.at(0)) ^ int2bv(arguments.at(1)));
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case evmasm::Instruction::NOT:
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return smtutil::Expression(u256(-1)) - arguments.at(0);
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case evmasm::Instruction::SHL:
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return smtutil::Expression::ite(
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arguments.at(0) > 255,
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constantValue(0),
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bv2int(int2bv(arguments.at(1)) << int2bv(arguments.at(0)))
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);
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case evmasm::Instruction::SHR:
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return smtutil::Expression::ite(
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arguments.at(0) > 255,
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constantValue(0),
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bv2int(int2bv(arguments.at(1)) >> int2bv(arguments.at(0)))
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);
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case evmasm::Instruction::SAR:
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return smtutil::Expression::ite(
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arguments.at(0) > 255,
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constantValue(0),
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bv2int(smtutil::Expression::ashr(int2bv(arguments.at(1)), int2bv(arguments.at(0))))
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);
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{
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smtutil::Expression underflow = m_solver->newVariable(uniqueName(), SortProvider::boolSort);
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m_solver->addAssertion(underflow || (variable == *x - *y));
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m_solver->addAssertion(!underflow || (variable == *x - *y + smtutil::Expression(bigint(1) << 256)));
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break;
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}
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//case evmasm::Instruction::MUL:
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// TODO encode constants?
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//case evmasm::Instruction::DIV:
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case evmasm::Instruction::ADDMOD:
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return smtutil::Expression::ite(
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arguments.at(2) == constantValue(0),
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constantValue(0),
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(arguments.at(0) + arguments.at(1)) % arguments.at(2)
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);
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case evmasm::Instruction::MULMOD:
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return smtutil::Expression::ite(
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arguments.at(2) == constantValue(0),
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constantValue(0),
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(arguments.at(0) * arguments.at(1)) % arguments.at(2)
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);
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// TODO SIGNEXTEND
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m_solver->addAssertion(variable < *z);
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break;
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case evmasm::Instruction::LT:
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m_solver->addAssertion(variable == (*x < *y));
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break;
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case evmasm::Instruction::GT:
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m_solver->addAssertion(variable == (*x > *y));
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break;
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// case evmasm::Instruction::SLT:
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// case evmasm::Instruction::SGT:
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// TODO
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case evmasm::Instruction::EQ:
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m_solver->addAssertion(variable == (*x == *y));
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break;
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case evmasm::Instruction::ISZERO:
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if (isBoolean(_arguments.at(0)))
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m_solver->addAssertion(variable == (!*x));
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else
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m_solver->addAssertion(variable == (*x <= smtutil::Expression(bigint(0))));
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break;
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case evmasm::Instruction::NOT:
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if (isBoolean(_arguments.at(0)))
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m_solver->addAssertion(variable == (!*x));
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else
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// TODO is this correct?
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m_solver->addAssertion(variable == ((smtutil::Expression(bigint(1) << 256) - 1) - *x));
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break;
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case evmasm::Instruction::AND:
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if (m_booleanVariables.count(_varName.str()))
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m_solver->addAssertion(variable == (*x && *y));
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else
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m_solver->addAssertion(variable <= *x && variable <= *y);
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break;
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case evmasm::Instruction::OR:
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if (m_booleanVariables.count(_varName.str()))
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m_solver->addAssertion(variable == (*x || *y));
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else
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{
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m_solver->addAssertion(variable >= *x && variable >= *y);
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m_solver->addAssertion(variable <= *x + *y);
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}
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break;
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// TODO all builtins whose return values can be restricted.
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default:
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break;
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}
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return newRestrictedVariable();
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}
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smtutil::Expression ReasoningBasedSimplifier::newRestrictedVariable(string const& _name, bool _boolean)
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{
|
||||
string name = _name.empty() ? uniqueName() : _name;
|
||||
if (_boolean)
|
||||
m_booleanVariables.insert(name);
|
||||
smtutil::Expression var = m_solver->newVariable(name, _boolean ? SortProvider::boolSort : defaultSort());
|
||||
if (!_boolean)
|
||||
m_solver->addAssertion(var <= smtutil::Expression(bigint(1) << 256) - 1);
|
||||
return var;
|
||||
}
|
||||
|
||||
string ReasoningBasedSimplifier::uniqueName()
|
||||
{
|
||||
return "expr_" + to_string(m_varCounter++);
|
||||
}
|
||||
bool ReasoningBasedSimplifier::makesInfeasible(smtutil::Expression _constraint)
|
||||
{
|
||||
m_solver->push();
|
||||
m_solver->addAssertion(_constraint);
|
||||
bool result = infeasible();
|
||||
m_solver->pop();
|
||||
return result;
|
||||
}
|
||||
|
||||
bool ReasoningBasedSimplifier::feasible()
|
||||
{
|
||||
CheckResult result = m_solver->check({}).first;
|
||||
return result == CheckResult::SATISFIABLE;
|
||||
}
|
||||
|
||||
bool ReasoningBasedSimplifier::infeasible()
|
||||
{
|
||||
CheckResult result = m_solver->check({}).first;
|
||||
return result == CheckResult::UNSATISFIABLE;
|
||||
}
|
||||
|
||||
YulString ReasoningBasedSimplifier::localVariableFromExpression(string const& _expressionName)
|
||||
{
|
||||
solAssert(_expressionName.substr(0, 4) == "yul_", "");
|
||||
return YulString(_expressionName.substr(4));
|
||||
|
||||
}
|
||||
|
||||
bool ReasoningBasedSimplifier::isBoolean(Expression const& _expression) const
|
||||
{
|
||||
return std::visit(GenericVisitor{
|
||||
[&](FunctionCall const& _functionCall)
|
||||
{
|
||||
if (auto const* dialect = dynamic_cast<EVMDialect const*>(&m_dialect))
|
||||
if (auto const* builtin = dialect->builtin(_functionCall.functionName.name))
|
||||
// TODO assert
|
||||
switch (*builtin->instruction)
|
||||
{
|
||||
case evmasm::Instruction::LT:
|
||||
case evmasm::Instruction::GT:
|
||||
case evmasm::Instruction::SLT:
|
||||
case evmasm::Instruction::SGT:
|
||||
case evmasm::Instruction::EQ:
|
||||
case evmasm::Instruction::ISZERO:
|
||||
return true;
|
||||
case evmasm::Instruction::AND:
|
||||
case evmasm::Instruction::OR:
|
||||
return
|
||||
isBoolean(_functionCall.arguments.at(0)) &&
|
||||
isBoolean(_functionCall.arguments.at(1));
|
||||
case evmasm::Instruction::NOT:
|
||||
return isBoolean(_functionCall.arguments.at(0));
|
||||
default:
|
||||
break;
|
||||
}
|
||||
return false;
|
||||
},
|
||||
[&](Identifier const& _identifier) -> bool
|
||||
{
|
||||
return m_booleanVariables.count("yul_" + _identifier.name.str());
|
||||
},
|
||||
[&](Literal const& _literal)
|
||||
{
|
||||
return _literal.kind == LiteralKind::Boolean;
|
||||
}
|
||||
}, _expression);
|
||||
}
|
||||
|
||||
shared_ptr<Sort> ReasoningBasedSimplifier::defaultSort() const
|
||||
{
|
||||
return SortProvider::intSort();
|
||||
}
|
||||
|
||||
smtutil::Expression ReasoningBasedSimplifier::literalValue(Literal const& _literal) const
|
||||
{
|
||||
return smtutil::Expression(valueOfLiteral(_literal));
|
||||
}
|
||||
|
@ -47,16 +47,17 @@ namespace solidity::yul
|
||||
*
|
||||
* Prerequisite: Disambiguator, SSATransform.
|
||||
*/
|
||||
class ReasoningBasedSimplifier: public ASTModifier, SMTSolver
|
||||
class ReasoningBasedSimplifier: public ASTModifier
|
||||
{
|
||||
public:
|
||||
static constexpr char const* name{"ReasoningBasedSimplifier"};
|
||||
static void run(OptimiserStepContext& _context, Block& _ast);
|
||||
static std::optional<std::string> invalidInCurrentEnvironment();
|
||||
|
||||
using ASTModifier::operator();
|
||||
void operator()(VariableDeclaration& _varDecl) override;
|
||||
void operator()(If& _if) override;
|
||||
void operator()(ForLoop& _for) override;
|
||||
void operator()(FunctionDefinition& _function) override;
|
||||
|
||||
private:
|
||||
explicit ReasoningBasedSimplifier(
|
||||
@ -64,12 +65,36 @@ private:
|
||||
std::set<YulString> const& _ssaVariables
|
||||
);
|
||||
|
||||
smtutil::Expression encodeEVMBuiltin(
|
||||
smtutil::Expression encodeExpression(
|
||||
Expression const& _expression
|
||||
);
|
||||
|
||||
void handleDeclaration(
|
||||
YulString _varName,
|
||||
evmasm::Instruction _instruction,
|
||||
std::vector<Expression> const& _arguments
|
||||
) override;
|
||||
);
|
||||
|
||||
smtutil::Expression newRestrictedVariable(std::string const& _name = {}, bool _boolean = false);
|
||||
std::string uniqueName();
|
||||
|
||||
bool makesInfeasible(smtutil::Expression _constraint);
|
||||
bool feasible();
|
||||
bool infeasible();
|
||||
|
||||
YulString localVariableFromExpression(std::string const& _expressionName);
|
||||
|
||||
bool isBoolean(Expression const& _expression) const;
|
||||
|
||||
std::shared_ptr<smtutil::Sort> defaultSort() const;
|
||||
smtutil::Expression literalValue(Literal const& _literal) const;
|
||||
Dialect const& m_dialect;
|
||||
std::set<YulString> const& m_ssaVariables;
|
||||
std::unique_ptr<smtutil::SolverInterface> m_solver;
|
||||
std::map<YulString, smtutil::Expression> m_variables;
|
||||
std::set<std::string> m_booleanVariables;
|
||||
|
||||
size_t m_varCounter = 0;
|
||||
};
|
||||
|
||||
}
|
||||
|
@ -24,7 +24,6 @@
|
||||
#include <test/Common.h>
|
||||
|
||||
#include <libyul/Object.h>
|
||||
#include <libyul/optimiser/ReasoningBasedSimplifier.h>
|
||||
#include <libyul/AsmPrinter.h>
|
||||
|
||||
#include <liblangutil/CharStreamProvider.h>
|
||||
@ -53,12 +52,6 @@ YulOptimizerTest::YulOptimizerTest(string const& _filename):
|
||||
BOOST_THROW_EXCEPTION(runtime_error("Filename path has to contain a directory: \"" + _filename + "\"."));
|
||||
m_optimizerStep = std::prev(std::prev(path.end()))->string();
|
||||
|
||||
if (m_optimizerStep == "reasoningBasedSimplifier" && (
|
||||
solidity::test::CommonOptions::get().disableSMT ||
|
||||
ReasoningBasedSimplifier::invalidInCurrentEnvironment()
|
||||
))
|
||||
m_shouldRun = false;
|
||||
|
||||
m_source = m_reader.source();
|
||||
|
||||
auto dialectName = m_reader.stringSetting("dialect", "evm");
|
||||
|
@ -283,8 +283,17 @@ YulOptimizerTestCommon::YulOptimizerTestCommon(
|
||||
}},
|
||||
{"reasoningBasedSimplifier", [&]() {
|
||||
disambiguate();
|
||||
ExpressionSplitter::run(*m_context, *m_ast);
|
||||
SSATransform::run(*m_context, *m_ast);
|
||||
RedundantAssignEliminator::run(*m_context, *m_ast);
|
||||
|
||||
ReasoningBasedSimplifier::run(*m_context, *m_object->code);
|
||||
}},
|
||||
|
||||
SSAReverser::run(*m_context, *m_ast);
|
||||
UnusedPruner::run(*m_context, *m_ast);
|
||||
ExpressionJoiner::run(*m_context, *m_ast);
|
||||
ExpressionJoiner::run(*m_context, *m_ast);
|
||||
}},
|
||||
{"equivalentFunctionCombiner", [&]() {
|
||||
disambiguate();
|
||||
ForLoopInitRewriter::run(*m_context, *m_ast);
|
||||
|
@ -16,16 +16,10 @@
|
||||
// for { }
|
||||
// iszero(_1)
|
||||
// {
|
||||
// if y
|
||||
// {
|
||||
// let _2 := 0
|
||||
// revert(_2, _2)
|
||||
// }
|
||||
// }
|
||||
// {
|
||||
// if y { continue }
|
||||
// sstore(1, 0)
|
||||
// let _2 := 0
|
||||
// revert(_2, _2)
|
||||
// }
|
||||
// { continue }
|
||||
// if y { revert(0, 0) }
|
||||
// }
|
||||
// }
|
||||
|
@ -40,6 +40,26 @@
|
||||
//
|
||||
// {
|
||||
// {
|
||||
// let _1 := gt(not(gcd(10, 15)), 1)
|
||||
// let _2 := gcd(10, 15)
|
||||
// let _3 := not(0)
|
||||
// let _4 := lt(or(1, add(gcd(10, 15), _3)), 1)
|
||||
// let _5 := gcd(10, 15)
|
||||
// let _6 := gcd(10, 15)
|
||||
// pop(keccak256(gcd(10, 15), or(gt(not(gcd(10, 15)), 1), 1)))
|
||||
// mstore(lt(or(gt(1, or(or(gt(or(or(or(gt(or(gt(_3, _6), 1), _5), _4), _2), 1), 1), _1), 1)), 1), 1), 1)
|
||||
// sstore(not(gcd(10, 15)), 1)
|
||||
// let _1 := 15
|
||||
// let _2 := 10
|
||||
// pop(gcd(_2, _1))
|
||||
// pop(gcd(_2, _1))
|
||||
// pop(gcd(_2, _1))
|
||||
// pop(gcd(_2, _1))
|
||||
// pop(gcd(_2, _1))
|
||||
// let _3 := 1
|
||||
// pop(keccak256(gcd(_2, _1), or(gt(not(gcd(_2, _1)), _3), _3)))
|
||||
// mstore(0, _3)
|
||||
// sstore(not(gcd(_2, _1)), _3)
|
||||
// let _1 := 1
|
||||
// let _2 := 15
|
||||
// let _3 := 10
|
||||
@ -53,6 +73,14 @@
|
||||
// mstore(lt(or(gt(_1, or(or(gt(or(or(or(gt(or(gt(_6, _9), _1), _8), _7), _5), _1), _1), _4), _1)), _1), _1), _1)
|
||||
// sstore(not(gcd(_3, _2)), _1)
|
||||
// sstore(0, 0)
|
||||
// sstore(2, 1)
|
||||
// extcodecopy(1, msize(), 1, 1)
|
||||
// sstore(0, 0)
|
||||
// sstore(3, 1)
|
||||
// sstore(2, _3)
|
||||
// extcodecopy(_3, msize(), _3, _3)
|
||||
// sstore(0, 0)
|
||||
// sstore(3, _3)
|
||||
// sstore(2, _1)
|
||||
// extcodecopy(_1, msize(), _1, _1)
|
||||
// sstore(3, _1)
|
||||
|
@ -0,0 +1,21 @@
|
||||
{
|
||||
let x := calldataload(0)
|
||||
let y := calldataload(1)
|
||||
if gt(x, 200) { revert(0, 0) }
|
||||
if gt(y, 600) { revert(0, 0) }
|
||||
if gt(x, not(y)) { revert(0, 0) }
|
||||
sstore(0, add(x, y))
|
||||
}
|
||||
// ====
|
||||
// EVMVersion: >=constantinople
|
||||
// ----
|
||||
// step: reasoningBasedSimplifier
|
||||
//
|
||||
// {
|
||||
// let x := calldataload(0)
|
||||
// let y := calldataload(1)
|
||||
// if gt(x, 200) { revert(0, 0) }
|
||||
// if gt(y, 600) { revert(0, 0) }
|
||||
// if 0 { }
|
||||
// sstore(0, add(x, y))
|
||||
// }
|
@ -6,8 +6,4 @@
|
||||
// ----
|
||||
// step: reasoningBasedSimplifier
|
||||
//
|
||||
// {
|
||||
// let x := 7
|
||||
// let y := 8
|
||||
// if 1 { }
|
||||
// }
|
||||
// { if 1 { } }
|
||||
|
@ -1,8 +1,8 @@
|
||||
{
|
||||
let vloc_x := calldataload(0)
|
||||
let vloc_y := calldataload(1)
|
||||
if lt(vloc_x, shl(100, 1)) {
|
||||
if lt(vloc_y, shl(100, 1)) {
|
||||
if lt(vloc_x, 0x1000000000000000) {
|
||||
if lt(vloc_y, 0x1000000000000000) {
|
||||
if iszero(and(iszero(iszero(vloc_x)), gt(vloc_y, div(not(0), vloc_x)))) {
|
||||
let vloc := mul(vloc_x, vloc_y)
|
||||
sstore(0, vloc)
|
||||
@ -18,14 +18,13 @@
|
||||
// {
|
||||
// let vloc_x := calldataload(0)
|
||||
// let vloc_y := calldataload(1)
|
||||
// if lt(vloc_x, shl(100, 1))
|
||||
// if lt(vloc_x, 0x1000000000000000)
|
||||
// {
|
||||
// if lt(vloc_y, shl(100, 1))
|
||||
// if lt(vloc_y, 0x1000000000000000)
|
||||
// {
|
||||
// if 1
|
||||
// if iszero(and(iszero(iszero(vloc_x)), gt(vloc_y, div(not(0), vloc_x))))
|
||||
// {
|
||||
// let vloc := mul(vloc_x, vloc_y)
|
||||
// sstore(0, vloc)
|
||||
// sstore(0, mul(vloc_x, vloc_y))
|
||||
// }
|
||||
// }
|
||||
// }
|
||||
|
@ -25,7 +25,13 @@
|
||||
// let y := calldataload(32)
|
||||
// let z := calldataload(64)
|
||||
// let result := mulmod(x, y, z)
|
||||
// if 0 { }
|
||||
// if and(and(lt(x, 1000), lt(y, 1000)), lt(z, 1000)) { if 1 { sstore(0, 9) } }
|
||||
// if and(and(gt(x, sub(0, 5)), eq(y, 2)), eq(z, 3)) { if 0 { } }
|
||||
// if gt(result, z) { sstore(0, 1) }
|
||||
// if and(and(lt(x, 1000), lt(y, 1000)), lt(z, 1000))
|
||||
// {
|
||||
// if eq(result, mod(mul(x, y), z)) { sstore(0, 9) }
|
||||
// }
|
||||
// if and(and(gt(x, sub(0, 5)), eq(y, 2)), eq(z, 3))
|
||||
// {
|
||||
// if eq(result, mod(mul(x, y), z)) { sstore(0, 5) }
|
||||
// }
|
||||
// }
|
||||
|
@ -11,6 +11,6 @@
|
||||
// {
|
||||
// let x := sub(0, 7)
|
||||
// let y := 2
|
||||
// if 1 { }
|
||||
// if 0 { }
|
||||
// if iszero(add(sdiv(x, y), 3)) { }
|
||||
// if iszero(add(sdiv(x, y), 4)) { }
|
||||
// }
|
||||
|
@ -14,8 +14,7 @@
|
||||
//
|
||||
// {
|
||||
// let x := calldataload(2)
|
||||
// let t := lt(x, 20)
|
||||
// if t
|
||||
// if lt(x, 20)
|
||||
// {
|
||||
// if 1 { }
|
||||
// if 1 { }
|
||||
|
@ -25,7 +25,10 @@
|
||||
// let t := calldataload(32)
|
||||
// if sgt(sub(y, 1), y)
|
||||
// {
|
||||
// if 1 { sstore(0, 7) }
|
||||
// if iszero(eq(y, t)) { if 1 { sstore(1, 7) } }
|
||||
// if eq(sdiv(y, sub(0, 1)), y) { sstore(0, 7) }
|
||||
// if iszero(eq(y, t))
|
||||
// {
|
||||
// if eq(sdiv(t, sub(0, 1)), sub(0, t)) { sstore(1, 7) }
|
||||
// }
|
||||
// }
|
||||
// }
|
||||
|
@ -38,16 +38,31 @@
|
||||
// let result := smod(x, y)
|
||||
// if eq(x, 7)
|
||||
// {
|
||||
// if eq(y, 5) { if 1 { sstore(0, 7) } }
|
||||
// if eq(y, sub(0, 5)) { if 1 { sstore(0, 7) } }
|
||||
// if eq(y, 5)
|
||||
// {
|
||||
// if eq(result, 2) { sstore(0, 7) }
|
||||
// }
|
||||
// if eq(y, sub(0, 5))
|
||||
// {
|
||||
// if eq(result, 2) { sstore(0, 7) }
|
||||
// }
|
||||
// }
|
||||
// if eq(x, sub(0, 7))
|
||||
// {
|
||||
// if eq(y, 5) { if 1 { sstore(0, 7) } }
|
||||
// if eq(y, sub(0, 5)) { if 1 { sstore(0, 7) } }
|
||||
// if eq(y, 5)
|
||||
// {
|
||||
// if eq(result, sub(0, 2)) { sstore(0, 7) }
|
||||
// }
|
||||
// if eq(y, sub(0, 5))
|
||||
// {
|
||||
// if eq(result, sub(0, 2)) { sstore(0, 7) }
|
||||
// }
|
||||
// }
|
||||
// if eq(x, sub(0, 5))
|
||||
// {
|
||||
// if eq(y, sub(0, 5)) { if 1 { sstore(0, 7) } }
|
||||
// if eq(y, sub(0, 5))
|
||||
// {
|
||||
// if eq(result, 0) { sstore(0, 7) }
|
||||
// }
|
||||
// }
|
||||
// }
|
||||
|
@ -8,8 +8,6 @@
|
||||
// step: reasoningBasedSimplifier
|
||||
//
|
||||
// {
|
||||
// let x := 7
|
||||
// let y := 8
|
||||
// if 1 { }
|
||||
// if 1 { }
|
||||
// }
|
||||
|
Loading…
Reference in New Issue
Block a user