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-rw-r--r--lib/Solver/IndependentSolver.cpp61
1 files changed, 17 insertions, 44 deletions
diff --git a/lib/Solver/IndependentSolver.cpp b/lib/Solver/IndependentSolver.cpp
index 84e7adb6..3594fecf 100644
--- a/lib/Solver/IndependentSolver.cpp
+++ b/lib/Solver/IndependentSolver.cpp
@@ -438,65 +438,38 @@ bool IndependentSolver::computeValue(const Query& query, ref<Expr> &result) {
return solver->impl->computeValue(Query(tmp, query.expr), result);
}
-bool canPerformConcreteAssignment(const std::vector<const Array*> &objects, const ref<Expr> e) {
- // Get the arrays used in the constraint. If an array isn't in objects we
- // don't have an assignment for it so skip it because can't evaluate to a
- // constant. This means we might not be checking every constraint which is
- // not ideal but the alternative would require getting an assignment for
- // all arrays which is wasteful given that the client didn't ask for them
- IndependentElementSet ieSet(e);
- for (std::vector<const Array *>::const_iterator ai = objects.begin(),
- ae = objects.end();
- ai != ae; ++ai) {
- ieSet.wholeObjects.erase(*ai);
- ieSet.elements.erase(*ai);
- }
-
- if (ieSet.wholeObjects.size() > 0 || ieSet.elements.size() > 0) {
- // There are arrays used in ``e`` that aren't in objects,
- // therefore we can't perform a complete assignment
- return false;
- }
- return true;
-}
-
// Helper function used only for assertions to make sure point created
-// during computeInitialValues is in fact correct. This function is
-// a "best effort" check because if the query uses an Array that an
-// assignment is not given for then that Query cannot be fully evaluated so
-// this function only checks that all expressions that can be fully
-// assigned to evaluate to true.
+// during computeInitialValues is in fact correct. The ``retMap`` is used
+// in the case ``objects`` doesn't contain all the assignments needed.
bool assertCreatedPointEvaluatesToTrue(const Query &query,
const std::vector<const Array*> &objects,
- std::vector< std::vector<unsigned char> > &values){
+ std::vector< std::vector<unsigned char> > &values,
+ std::map<const Array*, std::vector<unsigned char> > &retMap){
// _allowFreeValues is set to true so that if there are missing bytes in the assigment
// we will end up with a non ConstantExpr after evaluating the assignment and fail
Assignment assign = Assignment(objects, values, /*_allowFreeValues=*/true);
- for(ConstraintManager::constraint_iterator it = query.constraints.begin();
- it != query.constraints.end(); ++it){
- ref<Expr> constraint = *it;
- if (!canPerformConcreteAssignment(objects, constraint)) {
- // We have to skip checking assigning to this constraint
- continue;
- }
+ // Add any additional bindings.
+ // The semantics of std::map should be to not insert a (key, value)
+ // pair if it already exists so we should continue to use the assignment
+ // from ``objects`` and ``values``.
+ if (retMap.size() > 0)
+ assign.bindings.insert(retMap.begin(), retMap.end());
+ for(ConstraintManager::constraint_iterator it = query.constraints.begin();
+ it != query.constraints.end(); ++it){
ref<Expr> ret = assign.evaluate(*it);
- assert(isa<ConstantExpr>(ret) && "Could not use assignment to evaluate constraint");
+ assert(isa<ConstantExpr>(ret) && "assignment evaluation did not result in constant");
ref<ConstantExpr> evaluatedConstraint = dyn_cast<ConstantExpr>(ret);
if(evaluatedConstraint->isFalse()){
return false;
}
}
ref<Expr> neg = Expr::createIsZero(query.expr);
- if (canPerformConcreteAssignment(objects, neg)) {
- ref<Expr> q = assign.evaluate(neg);
- assert(isa<ConstantExpr>(q) && "assignment evaluation did not result in constant");
- return cast<ConstantExpr>(q)->isTrue();
- }
- // Can't assign to query expression
- return true;
+ ref<Expr> q = assign.evaluate(neg);
+ assert(isa<ConstantExpr>(q) && "assignment evaluation did not result in constant");
+ return cast<ConstantExpr>(q)->isTrue();
}
bool IndependentSolver::computeInitialValues(const Query& query,
@@ -569,7 +542,7 @@ bool IndependentSolver::computeInitialValues(const Query& query,
values.push_back(retMap[arr]);
}
}
- assert(assertCreatedPointEvaluatesToTrue(query, objects, values) && "should satisfy the equation");
+ assert(assertCreatedPointEvaluatesToTrue(query, objects, values, retMap) && "should satisfy the equation");
delete factors;
return true;
}