?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=http%3A%2F%2Feprints.imtlucca.it%2F1353%2F&rft.title=Constraint-Based+Correctness+Proofs+for+Logic+Program+Transformations&rft.creator=Pettorossi%2C+Alberto&rft.creator=Proietti%2C+Maurizio&rft.creator=Senni%2C+Valerio&rft.subject=QA75+Electronic+computers.+Computer+science&rft.description=Many+approaches+proposed+in+the+literature+for+proving+the+correctness+of+unfold%2Ffold+transformations+of+logic+programs+make+use+of+measures+associated+with+program+clauses.+When+from+a+program+P1+we+derive+a+program+P2+by+a+applying+a+sequence+of+transformations%2C+suitable+conditions+on+the+measures+of+the+clauses+in+P2+guarantee+that+the+transformation+of+P1+into+P2+is+correct%2C+that+is%2C+P1+and+P2+have+the+same+least+Herbrand+model.+In+the+approaches+proposed+so+far%2C+clause+measures+are+fixed+in+advance%2C+independently+of+the+transformations+to+be+proved+correct.+In+this+paper+we+propose+a+method+for+the+automatic+generation+of+clause+measures+which%2C+instead%2C+takes+into+account+the+particular+program+transformation+at+hand.+During+the+application+of+a+sequence+of+transformations+we+construct+a+system+of+linear+equalities+and+inequalities%0D%0Aover+nonnegative+integers+whose+unknowns+are+the+clause+measures+to+be+found%2C+and+the+correctness+of+the+transformation+is+guaranteed+by+the+satisfiability+of+that+system.+Through+some+examples+we+show+that+our+method+is+more+powerful+and+practical+than+other+methods+proposed+in+the+literature.+In+particular%2C+we+are+able+to+establish+in+a+fully+automatic+way+the+correctness+of+program+transformations+which%2C+by+using+other+methods%2C+are+proved+correct+at+the+expense+of+fixing+in+advance+sophisticated+clause+measures.&rft.publisher=IASI-CNR&rft.date=2011&rft.type=Working+Paper&rft.type=NonPeerReviewed&rft.identifier=++Pettorossi%2C+Alberto+and+Proietti%2C+Maurizio+and+Senni%2C+Valerio++Constraint-Based+Correctness+Proofs+for+Logic+Program+Transformations.++Technical+Report++%2324%2F2011++++IASI-CNR+++++++++&rft.relation=http%3A%2F%2Fwww.iasi.cnr.it%2F~proietti%2Fpapers%2FIASI_R_11-24_PetProSen.pdf