/usr/bin/java -Xmx8000000000 -Xss4m -jar ./plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar -data @noDefault -ultimatedata ./data -tc ../../../trunk/examples/toolchains/AutomizerC.xml --traceabstraction.trace.refinement.strategy FIXED_PREFERENCES --traceabstraction.compute.interpolants.along.a.counterexample Craig_NestedInterpolation --traceabstraction.smt.solver Internal_SMTInterpol --traceabstraction.compute.trace.for.counterexample.result false --traceabstraction.use.minimal.unsat.core.enumeration true -s ../../../trunk/examples/settings/default/automizer/svcomp-Reach-32bit-Automizer_Default.epf -i ../../../trunk/examples/svcomp/seq-mthreaded-reduced/pals_floodmax.5.2.ufo.UNBOUNDED.pals.c.v+lhb-reducer.c -------------------------------------------------------------------------------- This is Ultimate 0.1.25-5644d1e-m [2020-08-18 16:26:34,302 INFO L177 SettingsManager]: Resetting all preferences to default values... [2020-08-18 16:26:34,306 INFO L181 SettingsManager]: Resetting UltimateCore preferences to default values [2020-08-18 16:26:34,345 INFO L184 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... [2020-08-18 16:26:34,346 INFO L181 SettingsManager]: Resetting Boogie Preprocessor preferences to default values [2020-08-18 16:26:34,357 INFO L181 SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values [2020-08-18 16:26:34,359 INFO L181 SettingsManager]: Resetting Abstract Interpretation preferences to default values [2020-08-18 16:26:34,362 INFO L181 SettingsManager]: Resetting LassoRanker preferences to default values [2020-08-18 16:26:34,363 INFO L181 SettingsManager]: Resetting Reaching Definitions preferences to default values [2020-08-18 16:26:34,368 INFO L181 SettingsManager]: Resetting SyntaxChecker preferences to default values [2020-08-18 16:26:34,368 INFO L181 SettingsManager]: Resetting Sifa preferences to default values [2020-08-18 16:26:34,371 INFO L184 SettingsManager]: Büchi Program Product provides no preferences, ignoring... [2020-08-18 16:26:34,371 INFO L181 SettingsManager]: Resetting LTL2Aut preferences to default values [2020-08-18 16:26:34,374 INFO L181 SettingsManager]: Resetting PEA to Boogie preferences to default values [2020-08-18 16:26:34,376 INFO L181 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2020-08-18 16:26:34,378 INFO L181 SettingsManager]: Resetting ChcToBoogie preferences to default values [2020-08-18 16:26:34,380 INFO L181 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2020-08-18 16:26:34,381 INFO L181 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2020-08-18 16:26:34,384 INFO L181 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2020-08-18 16:26:34,389 INFO L181 SettingsManager]: Resetting CodeCheck preferences to default values [2020-08-18 16:26:34,392 INFO L181 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2020-08-18 16:26:34,393 INFO L181 SettingsManager]: Resetting RCFGBuilder preferences to default values [2020-08-18 16:26:34,394 INFO L181 SettingsManager]: Resetting Referee preferences to default values [2020-08-18 16:26:34,395 INFO L181 SettingsManager]: Resetting TraceAbstraction preferences to default values [2020-08-18 16:26:34,400 INFO L184 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... [2020-08-18 16:26:34,400 INFO L184 SettingsManager]: TraceAbstractionWithAFAs provides no preferences, ignoring... [2020-08-18 16:26:34,400 INFO L181 SettingsManager]: Resetting TreeAutomizer preferences to default values [2020-08-18 16:26:34,403 INFO L181 SettingsManager]: Resetting IcfgToChc preferences to default values [2020-08-18 16:26:34,403 INFO L181 SettingsManager]: Resetting IcfgTransformer preferences to default values [2020-08-18 16:26:34,405 INFO L184 SettingsManager]: ReqToTest provides no preferences, ignoring... [2020-08-18 16:26:34,405 INFO L181 SettingsManager]: Resetting Boogie Printer preferences to default values [2020-08-18 16:26:34,406 INFO L181 SettingsManager]: Resetting ChcSmtPrinter preferences to default values [2020-08-18 16:26:34,406 INFO L181 SettingsManager]: Resetting ReqPrinter preferences to default values [2020-08-18 16:26:34,407 INFO L181 SettingsManager]: Resetting Witness Printer preferences to default values [2020-08-18 16:26:34,408 INFO L184 SettingsManager]: Boogie PL CUP Parser provides no preferences, ignoring... [2020-08-18 16:26:34,409 INFO L181 SettingsManager]: Resetting CDTParser preferences to default values [2020-08-18 16:26:34,409 INFO L184 SettingsManager]: AutomataScriptParser provides no preferences, ignoring... [2020-08-18 16:26:34,409 INFO L184 SettingsManager]: ReqParser provides no preferences, ignoring... [2020-08-18 16:26:34,410 INFO L181 SettingsManager]: Resetting SmtParser preferences to default values [2020-08-18 16:26:34,410 INFO L181 SettingsManager]: Resetting Witness Parser preferences to default values [2020-08-18 16:26:34,412 INFO L188 SettingsManager]: Finished resetting all preferences to default values... [2020-08-18 16:26:34,412 INFO L101 SettingsManager]: Beginning loading settings from /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/settings/default/automizer/svcomp-Reach-32bit-Automizer_Default.epf [2020-08-18 16:26:34,457 INFO L113 SettingsManager]: Loading preferences was successful [2020-08-18 16:26:34,457 INFO L115 SettingsManager]: Preferences different from defaults after loading the file: [2020-08-18 16:26:34,459 INFO L136 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2020-08-18 16:26:34,460 INFO L138 SettingsManager]: * Create parallel compositions if possible=false [2020-08-18 16:26:34,460 INFO L138 SettingsManager]: * Use SBE=true [2020-08-18 16:26:34,460 INFO L136 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2020-08-18 16:26:34,461 INFO L138 SettingsManager]: * sizeof long=4 [2020-08-18 16:26:34,461 INFO L138 SettingsManager]: * Overapproximate operations on floating types=true [2020-08-18 16:26:34,461 INFO L138 SettingsManager]: * sizeof POINTER=4 [2020-08-18 16:26:34,461 INFO L138 SettingsManager]: * Check division by zero=IGNORE [2020-08-18 16:26:34,462 INFO L138 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2020-08-18 16:26:34,463 INFO L138 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2020-08-18 16:26:34,463 INFO L138 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2020-08-18 16:26:34,463 INFO L138 SettingsManager]: * sizeof long double=12 [2020-08-18 16:26:34,463 INFO L138 SettingsManager]: * Check if freed pointer was valid=false [2020-08-18 16:26:34,464 INFO L138 SettingsManager]: * Use constant arrays=true [2020-08-18 16:26:34,464 INFO L138 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2020-08-18 16:26:34,464 INFO L136 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2020-08-18 16:26:34,464 INFO L138 SettingsManager]: * Size of a code block=SequenceOfStatements [2020-08-18 16:26:34,464 INFO L138 SettingsManager]: * To the following directory=./dump/ [2020-08-18 16:26:34,465 INFO L138 SettingsManager]: * SMT solver=External_DefaultMode [2020-08-18 16:26:34,465 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2020-08-18 16:26:34,465 INFO L136 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2020-08-18 16:26:34,465 INFO L138 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2020-08-18 16:26:34,465 INFO L138 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles [2020-08-18 16:26:34,466 INFO L138 SettingsManager]: * Trace refinement strategy=CAMEL [2020-08-18 16:26:34,466 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2020-08-18 16:26:34,466 INFO L138 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2020-08-18 16:26:34,466 INFO L138 SettingsManager]: * Trace refinement exception blacklist=NONE [2020-08-18 16:26:34,466 INFO L138 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Trace refinement strategy -> FIXED_PREFERENCES Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Compute Interpolants along a Counterexample -> Craig_NestedInterpolation Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: SMT solver -> Internal_SMTInterpol Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Compute trace for counterexample result -> false Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Use minimal unsat core enumeration -> true [2020-08-18 16:26:34,751 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2020-08-18 16:26:34,768 INFO L258 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2020-08-18 16:26:34,772 INFO L214 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2020-08-18 16:26:34,773 INFO L271 PluginConnector]: Initializing CDTParser... [2020-08-18 16:26:34,774 INFO L275 PluginConnector]: CDTParser initialized [2020-08-18 16:26:34,774 INFO L429 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/svcomp/seq-mthreaded-reduced/pals_floodmax.5.2.ufo.UNBOUNDED.pals.c.v+lhb-reducer.c [2020-08-18 16:26:34,850 INFO L220 CDTParser]: Created temporary CDT project at /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/c19625c69/baf86128c87446c2947e43792fbacab7/FLAGef259c84f [2020-08-18 16:26:35,551 INFO L306 CDTParser]: Found 1 translation units. [2020-08-18 16:26:35,552 INFO L160 CDTParser]: Scanning /storage/repos/ultimate-2/trunk/examples/svcomp/seq-mthreaded-reduced/pals_floodmax.5.2.ufo.UNBOUNDED.pals.c.v+lhb-reducer.c [2020-08-18 16:26:35,571 INFO L349 CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/c19625c69/baf86128c87446c2947e43792fbacab7/FLAGef259c84f [2020-08-18 16:26:35,700 INFO L357 CDTParser]: Successfully deleted /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/c19625c69/baf86128c87446c2947e43792fbacab7 [2020-08-18 16:26:35,708 INFO L296 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2020-08-18 16:26:35,709 INFO L131 ToolchainWalker]: Walking toolchain with 4 elements. [2020-08-18 16:26:35,710 INFO L113 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2020-08-18 16:26:35,711 INFO L271 PluginConnector]: Initializing CACSL2BoogieTranslator... [2020-08-18 16:26:35,714 INFO L275 PluginConnector]: CACSL2BoogieTranslator initialized [2020-08-18 16:26:35,715 INFO L185 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 18.08 04:26:35" (1/1) ... [2020-08-18 16:26:35,718 INFO L205 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@1dc260e4 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:35, skipping insertion in model container [2020-08-18 16:26:35,718 INFO L185 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 18.08 04:26:35" (1/1) ... [2020-08-18 16:26:35,726 INFO L145 MainTranslator]: Starting translation in SV-COMP mode [2020-08-18 16:26:35,906 INFO L178 MainTranslator]: Built tables and reachable declarations [2020-08-18 16:26:37,461 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-08-18 16:26:37,476 INFO L203 MainTranslator]: Completed pre-run [2020-08-18 16:26:38,507 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-08-18 16:26:38,561 INFO L208 MainTranslator]: Completed translation [2020-08-18 16:26:38,563 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:38 WrapperNode [2020-08-18 16:26:38,563 INFO L132 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2020-08-18 16:26:38,565 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2020-08-18 16:26:38,565 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2020-08-18 16:26:38,565 INFO L275 PluginConnector]: Boogie Preprocessor initialized [2020-08-18 16:26:38,586 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:38" (1/1) ... [2020-08-18 16:26:38,587 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:38" (1/1) ... [2020-08-18 16:26:38,671 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:38" (1/1) ... [2020-08-18 16:26:38,672 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:38" (1/1) ... [2020-08-18 16:26:38,734 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:38" (1/1) ... [2020-08-18 16:26:38,775 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:38" (1/1) ... [2020-08-18 16:26:38,809 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:38" (1/1) ... [2020-08-18 16:26:38,841 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2020-08-18 16:26:38,842 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2020-08-18 16:26:38,842 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2020-08-18 16:26:38,843 INFO L275 PluginConnector]: RCFGBuilder initialized [2020-08-18 16:26:38,844 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:38" (1/1) ... No working directory specified, using /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/z3 Starting monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2020-08-18 16:26:38,955 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.init [2020-08-18 16:26:38,955 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2020-08-18 16:26:38,956 INFO L138 BoogieDeclarations]: Found implementation of procedure assume_abort_if_not [2020-08-18 16:26:38,956 INFO L138 BoogieDeclarations]: Found implementation of procedure main [2020-08-18 16:26:38,956 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_error [2020-08-18 16:26:38,957 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_char [2020-08-18 16:26:38,958 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_uchar [2020-08-18 16:26:38,958 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_bool [2020-08-18 16:26:38,958 INFO L130 BoogieDeclarations]: Found specification of procedure assert [2020-08-18 16:26:38,958 INFO L130 BoogieDeclarations]: Found specification of procedure abort [2020-08-18 16:26:38,959 INFO L130 BoogieDeclarations]: Found specification of procedure assume_abort_if_not [2020-08-18 16:26:38,960 INFO L130 BoogieDeclarations]: Found specification of procedure read [2020-08-18 16:26:38,960 INFO L130 BoogieDeclarations]: Found specification of procedure write [2020-08-18 16:26:38,960 INFO L130 BoogieDeclarations]: Found specification of procedure node1 [2020-08-18 16:26:38,960 INFO L130 BoogieDeclarations]: Found specification of procedure node2 [2020-08-18 16:26:38,961 INFO L130 BoogieDeclarations]: Found specification of procedure node3 [2020-08-18 16:26:38,962 INFO L130 BoogieDeclarations]: Found specification of procedure node4 [2020-08-18 16:26:38,962 INFO L130 BoogieDeclarations]: Found specification of procedure node5 [2020-08-18 16:26:38,962 INFO L130 BoogieDeclarations]: Found specification of procedure init [2020-08-18 16:26:38,963 INFO L130 BoogieDeclarations]: Found specification of procedure check [2020-08-18 16:26:38,963 INFO L130 BoogieDeclarations]: Found specification of procedure main [2020-08-18 16:26:38,963 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.init [2020-08-18 16:26:38,963 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2020-08-18 16:26:43,111 INFO L290 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2020-08-18 16:26:43,112 INFO L295 CfgBuilder]: Removed 0 assume(true) statements. [2020-08-18 16:26:43,123 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 18.08 04:26:43 BoogieIcfgContainer [2020-08-18 16:26:43,124 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2020-08-18 16:26:43,125 INFO L113 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2020-08-18 16:26:43,125 INFO L271 PluginConnector]: Initializing TraceAbstraction... [2020-08-18 16:26:43,128 INFO L275 PluginConnector]: TraceAbstraction initialized [2020-08-18 16:26:43,128 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 18.08 04:26:35" (1/3) ... [2020-08-18 16:26:43,129 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@11ade407 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 18.08 04:26:43, skipping insertion in model container [2020-08-18 16:26:43,129 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 04:26:38" (2/3) ... [2020-08-18 16:26:43,130 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@11ade407 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 18.08 04:26:43, skipping insertion in model container [2020-08-18 16:26:43,130 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 18.08 04:26:43" (3/3) ... [2020-08-18 16:26:43,132 INFO L109 eAbstractionObserver]: Analyzing ICFG pals_floodmax.5.2.ufo.UNBOUNDED.pals.c.v+lhb-reducer.c [2020-08-18 16:26:43,142 INFO L157 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:Craig_NestedInterpolation Determinization: PREDICATE_ABSTRACTION [2020-08-18 16:26:43,150 INFO L169 ceAbstractionStarter]: Appying trace abstraction to program that has 2 error locations. [2020-08-18 16:26:43,164 INFO L251 AbstractCegarLoop]: Starting to check reachability of 2 error locations. [2020-08-18 16:26:43,192 INFO L375 AbstractCegarLoop]: Interprodecural is true [2020-08-18 16:26:43,192 INFO L376 AbstractCegarLoop]: Hoare is true [2020-08-18 16:26:43,192 INFO L377 AbstractCegarLoop]: Compute interpolants for Craig_NestedInterpolation [2020-08-18 16:26:43,192 INFO L378 AbstractCegarLoop]: Backedges is STRAIGHT_LINE [2020-08-18 16:26:43,192 INFO L379 AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION [2020-08-18 16:26:43,193 INFO L380 AbstractCegarLoop]: Difference is false [2020-08-18 16:26:43,193 INFO L381 AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA [2020-08-18 16:26:43,193 INFO L385 AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce======== [2020-08-18 16:26:43,232 INFO L276 IsEmpty]: Start isEmpty. Operand 1393 states. [2020-08-18 16:26:43,281 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 474 [2020-08-18 16:26:43,281 INFO L414 BasicCegarLoop]: Found error trace [2020-08-18 16:26:43,283 INFO L422 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-08-18 16:26:43,283 INFO L427 AbstractCegarLoop]: === Iteration 1 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION, mainErr1ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-18 16:26:43,290 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-18 16:26:43,291 INFO L82 PathProgramCache]: Analyzing trace with hash -1447603851, now seen corresponding path program 1 times [2020-08-18 16:26:43,301 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-18 16:26:43,301 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [2027330449] [2020-08-18 16:26:43,302 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-18 16:26:45,056 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 16:26:46,729 WARN L193 SmtUtils]: Spent 960.00 ms on a formula simplification that was a NOOP. DAG size: 385 [2020-08-18 16:26:46,732 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-18 16:26:46,742 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 16:26:47,662 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-08-18 16:26:47,663 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [2027330449] [2020-08-18 16:26:47,665 INFO L220 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-08-18 16:26:47,666 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2020-08-18 16:26:47,667 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [2036994199] [2020-08-18 16:26:47,676 INFO L459 AbstractCegarLoop]: Interpolant automaton has 5 states [2020-08-18 16:26:47,677 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-18 16:26:47,692 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2020-08-18 16:26:47,693 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2020-08-18 16:26:47,695 INFO L87 Difference]: Start difference. First operand 1393 states. Second operand 5 states. [2020-08-18 16:27:04,642 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-08-18 16:27:04,643 INFO L93 Difference]: Finished difference Result 4125 states and 7467 transitions. [2020-08-18 16:27:04,645 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 6 states. [2020-08-18 16:27:04,646 INFO L78 Accepts]: Start accepts. Automaton has 5 states. Word has length 473 [2020-08-18 16:27:04,647 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-08-18 16:27:04,693 INFO L225 Difference]: With dead ends: 4125 [2020-08-18 16:27:04,693 INFO L226 Difference]: Without dead ends: 2741 [2020-08-18 16:27:04,705 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 7 GetRequests, 3 SyntacticMatches, 0 SemanticMatches, 4 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 1.0s TimeCoverageRelationStatistics Valid=11, Invalid=19, Unknown=0, NotChecked=0, Total=30 [2020-08-18 16:27:04,730 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 2741 states. [2020-08-18 16:27:04,914 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 2741 to 2688. [2020-08-18 16:27:04,916 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 2688 states. [2020-08-18 16:27:04,927 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 2688 states to 2688 states and 4398 transitions. [2020-08-18 16:27:04,929 INFO L78 Accepts]: Start accepts. Automaton has 2688 states and 4398 transitions. Word has length 473 [2020-08-18 16:27:04,931 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-08-18 16:27:04,931 INFO L479 AbstractCegarLoop]: Abstraction has 2688 states and 4398 transitions. [2020-08-18 16:27:04,931 INFO L480 AbstractCegarLoop]: Interpolant automaton has 5 states. [2020-08-18 16:27:04,931 INFO L276 IsEmpty]: Start isEmpty. Operand 2688 states and 4398 transitions. [2020-08-18 16:27:04,946 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 476 [2020-08-18 16:27:04,946 INFO L414 BasicCegarLoop]: Found error trace [2020-08-18 16:27:04,947 INFO L422 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-08-18 16:27:04,947 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0 [2020-08-18 16:27:04,947 INFO L427 AbstractCegarLoop]: === Iteration 2 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION, mainErr1ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-18 16:27:04,948 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-18 16:27:04,948 INFO L82 PathProgramCache]: Analyzing trace with hash -369254340, now seen corresponding path program 1 times [2020-08-18 16:27:04,948 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-18 16:27:04,949 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [1348953826] [2020-08-18 16:27:04,949 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-18 16:27:05,305 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 16:27:06,902 WARN L193 SmtUtils]: Spent 1.17 s on a formula simplification that was a NOOP. DAG size: 385 [2020-08-18 16:27:06,905 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-18 16:27:06,917 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 16:27:07,748 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-08-18 16:27:07,749 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [1348953826] [2020-08-18 16:27:07,749 INFO L220 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-08-18 16:27:07,750 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [4] imperfect sequences [] total 4 [2020-08-18 16:27:07,750 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [643373220] [2020-08-18 16:27:07,752 INFO L459 AbstractCegarLoop]: Interpolant automaton has 4 states [2020-08-18 16:27:07,753 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-18 16:27:07,753 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2020-08-18 16:27:07,753 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2020-08-18 16:27:07,753 INFO L87 Difference]: Start difference. First operand 2688 states and 4398 transitions. Second operand 4 states. [2020-08-18 16:27:25,809 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-08-18 16:27:25,810 INFO L93 Difference]: Finished difference Result 7793 states and 12713 transitions. [2020-08-18 16:27:25,810 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 4 states. [2020-08-18 16:27:25,811 INFO L78 Accepts]: Start accepts. Automaton has 4 states. Word has length 475 [2020-08-18 16:27:25,812 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-08-18 16:27:25,838 INFO L225 Difference]: With dead ends: 7793 [2020-08-18 16:27:25,838 INFO L226 Difference]: Without dead ends: 5319 [2020-08-18 16:27:25,845 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 5 GetRequests, 3 SyntacticMatches, 0 SemanticMatches, 2 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 1.2s TimeCoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2020-08-18 16:27:25,853 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 5319 states. [2020-08-18 16:27:26,024 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 5319 to 5268. [2020-08-18 16:27:26,025 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 5268 states. [2020-08-18 16:27:26,045 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 5268 states to 5268 states and 8596 transitions. [2020-08-18 16:27:26,045 INFO L78 Accepts]: Start accepts. Automaton has 5268 states and 8596 transitions. Word has length 475 [2020-08-18 16:27:26,047 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-08-18 16:27:26,048 INFO L479 AbstractCegarLoop]: Abstraction has 5268 states and 8596 transitions. [2020-08-18 16:27:26,048 INFO L480 AbstractCegarLoop]: Interpolant automaton has 4 states. [2020-08-18 16:27:26,048 INFO L276 IsEmpty]: Start isEmpty. Operand 5268 states and 8596 transitions. [2020-08-18 16:27:26,067 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 477 [2020-08-18 16:27:26,068 INFO L414 BasicCegarLoop]: Found error trace [2020-08-18 16:27:26,069 INFO L422 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-08-18 16:27:26,070 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable1 [2020-08-18 16:27:26,070 INFO L427 AbstractCegarLoop]: === Iteration 3 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION, mainErr1ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-18 16:27:26,074 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-18 16:27:26,075 INFO L82 PathProgramCache]: Analyzing trace with hash -567190772, now seen corresponding path program 1 times [2020-08-18 16:27:26,075 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-18 16:27:26,075 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [1563885932] [2020-08-18 16:27:26,076 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-18 16:27:26,147 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 16:27:27,291 WARN L193 SmtUtils]: Spent 938.00 ms on a formula simplification that was a NOOP. DAG size: 385 [2020-08-18 16:27:27,292 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-18 16:27:27,300 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 16:27:27,466 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-08-18 16:27:27,466 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [1563885932] [2020-08-18 16:27:27,467 INFO L220 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-08-18 16:27:27,467 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [4] imperfect sequences [] total 4 [2020-08-18 16:27:27,467 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1742207101] [2020-08-18 16:27:27,468 INFO L459 AbstractCegarLoop]: Interpolant automaton has 4 states [2020-08-18 16:27:27,468 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-18 16:27:27,468 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2020-08-18 16:27:27,469 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2020-08-18 16:27:27,469 INFO L87 Difference]: Start difference. First operand 5268 states and 8596 transitions. Second operand 4 states.