/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 false -s ../../../trunk/examples/settings/default/automizer/svcomp-Reach-32bit-Automizer_Default.epf -i ../../../trunk/examples/svcomp/seq-mthreaded-reduced/pals_floodmax.5.2.ufo.BOUNDED-10.pals.c.v+lhb-reducer.c -------------------------------------------------------------------------------- This is Ultimate 0.1.25-5644d1e-m [2020-08-18 15:38:11,338 INFO L177 SettingsManager]: Resetting all preferences to default values... [2020-08-18 15:38:11,341 INFO L181 SettingsManager]: Resetting UltimateCore preferences to default values [2020-08-18 15:38:11,377 INFO L184 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... [2020-08-18 15:38:11,377 INFO L181 SettingsManager]: Resetting Boogie Preprocessor preferences to default values [2020-08-18 15:38:11,378 INFO L181 SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values [2020-08-18 15:38:11,379 INFO L181 SettingsManager]: Resetting Abstract Interpretation preferences to default values [2020-08-18 15:38:11,381 INFO L181 SettingsManager]: Resetting LassoRanker preferences to default values [2020-08-18 15:38:11,382 INFO L181 SettingsManager]: Resetting Reaching Definitions preferences to default values [2020-08-18 15:38:11,383 INFO L181 SettingsManager]: Resetting SyntaxChecker preferences to default values [2020-08-18 15:38:11,384 INFO L181 SettingsManager]: Resetting Sifa preferences to default values [2020-08-18 15:38:11,385 INFO L184 SettingsManager]: Büchi Program Product provides no preferences, ignoring... [2020-08-18 15:38:11,385 INFO L181 SettingsManager]: Resetting LTL2Aut preferences to default values [2020-08-18 15:38:11,386 INFO L181 SettingsManager]: Resetting PEA to Boogie preferences to default values [2020-08-18 15:38:11,387 INFO L181 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2020-08-18 15:38:11,388 INFO L181 SettingsManager]: Resetting ChcToBoogie preferences to default values [2020-08-18 15:38:11,389 INFO L181 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2020-08-18 15:38:11,390 INFO L181 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2020-08-18 15:38:11,391 INFO L181 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2020-08-18 15:38:11,393 INFO L181 SettingsManager]: Resetting CodeCheck preferences to default values [2020-08-18 15:38:11,394 INFO L181 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2020-08-18 15:38:11,395 INFO L181 SettingsManager]: Resetting RCFGBuilder preferences to default values [2020-08-18 15:38:11,396 INFO L181 SettingsManager]: Resetting Referee preferences to default values [2020-08-18 15:38:11,397 INFO L181 SettingsManager]: Resetting TraceAbstraction preferences to default values [2020-08-18 15:38:11,399 INFO L184 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... [2020-08-18 15:38:11,400 INFO L184 SettingsManager]: TraceAbstractionWithAFAs provides no preferences, ignoring... [2020-08-18 15:38:11,400 INFO L181 SettingsManager]: Resetting TreeAutomizer preferences to default values [2020-08-18 15:38:11,401 INFO L181 SettingsManager]: Resetting IcfgToChc preferences to default values [2020-08-18 15:38:11,401 INFO L181 SettingsManager]: Resetting IcfgTransformer preferences to default values [2020-08-18 15:38:11,402 INFO L184 SettingsManager]: ReqToTest provides no preferences, ignoring... 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[2020-08-18 15:38:11,406 INFO L181 SettingsManager]: Resetting SmtParser preferences to default values [2020-08-18 15:38:11,407 INFO L181 SettingsManager]: Resetting Witness Parser preferences to default values [2020-08-18 15:38:11,408 INFO L188 SettingsManager]: Finished resetting all preferences to default values... [2020-08-18 15:38:11,408 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 15:38:11,438 INFO L113 SettingsManager]: Loading preferences was successful [2020-08-18 15:38:11,438 INFO L115 SettingsManager]: Preferences different from defaults after loading the file: [2020-08-18 15:38:11,439 INFO L136 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2020-08-18 15:38:11,440 INFO L138 SettingsManager]: * Create parallel compositions if possible=false [2020-08-18 15:38:11,440 INFO L138 SettingsManager]: * Use SBE=true [2020-08-18 15:38:11,440 INFO L136 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2020-08-18 15:38:11,440 INFO L138 SettingsManager]: * sizeof long=4 [2020-08-18 15:38:11,440 INFO L138 SettingsManager]: * Overapproximate operations on floating types=true [2020-08-18 15:38:11,441 INFO L138 SettingsManager]: * sizeof POINTER=4 [2020-08-18 15:38:11,441 INFO L138 SettingsManager]: * Check division by zero=IGNORE [2020-08-18 15:38:11,441 INFO L138 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2020-08-18 15:38:11,441 INFO L138 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2020-08-18 15:38:11,441 INFO L138 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2020-08-18 15:38:11,441 INFO L138 SettingsManager]: * sizeof long double=12 [2020-08-18 15:38:11,442 INFO L138 SettingsManager]: * Check if freed pointer was valid=false [2020-08-18 15:38:11,442 INFO L138 SettingsManager]: * Use constant arrays=true [2020-08-18 15:38:11,442 INFO L138 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2020-08-18 15:38:11,442 INFO L136 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2020-08-18 15:38:11,442 INFO L138 SettingsManager]: * Size of a code block=SequenceOfStatements [2020-08-18 15:38:11,443 INFO L138 SettingsManager]: * To the following directory=./dump/ [2020-08-18 15:38:11,443 INFO L138 SettingsManager]: * SMT solver=External_DefaultMode [2020-08-18 15:38:11,443 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2020-08-18 15:38:11,443 INFO L136 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2020-08-18 15:38:11,444 INFO L138 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2020-08-18 15:38:11,444 INFO L138 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles [2020-08-18 15:38:11,444 INFO L138 SettingsManager]: * Trace refinement strategy=CAMEL [2020-08-18 15:38:11,444 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2020-08-18 15:38:11,444 INFO L138 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2020-08-18 15:38:11,444 INFO L138 SettingsManager]: * Trace refinement exception blacklist=NONE [2020-08-18 15:38:11,445 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 -> false [2020-08-18 15:38:11,748 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2020-08-18 15:38:11,767 INFO L258 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2020-08-18 15:38:11,773 INFO L214 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2020-08-18 15:38:11,774 INFO L271 PluginConnector]: Initializing CDTParser... [2020-08-18 15:38:11,774 INFO L275 PluginConnector]: CDTParser initialized [2020-08-18 15:38:11,776 INFO L429 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/svcomp/seq-mthreaded-reduced/pals_floodmax.5.2.ufo.BOUNDED-10.pals.c.v+lhb-reducer.c [2020-08-18 15:38:11,855 INFO L220 CDTParser]: Created temporary CDT project at /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/b5380f3b3/b0a0657ee7304b2d945680a5038e34d2/FLAGe7a9b53f4 [2020-08-18 15:38:12,589 INFO L306 CDTParser]: Found 1 translation units. [2020-08-18 15:38:12,590 INFO L160 CDTParser]: Scanning /storage/repos/ultimate-2/trunk/examples/svcomp/seq-mthreaded-reduced/pals_floodmax.5.2.ufo.BOUNDED-10.pals.c.v+lhb-reducer.c [2020-08-18 15:38:12,609 INFO L349 CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/b5380f3b3/b0a0657ee7304b2d945680a5038e34d2/FLAGe7a9b53f4 [2020-08-18 15:38:12,674 INFO L357 CDTParser]: Successfully deleted /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/b5380f3b3/b0a0657ee7304b2d945680a5038e34d2 [2020-08-18 15:38:12,683 INFO L296 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2020-08-18 15:38:12,685 INFO L131 ToolchainWalker]: Walking toolchain with 4 elements. [2020-08-18 15:38:12,686 INFO L113 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2020-08-18 15:38:12,686 INFO L271 PluginConnector]: Initializing CACSL2BoogieTranslator... [2020-08-18 15:38:12,689 INFO L275 PluginConnector]: CACSL2BoogieTranslator initialized [2020-08-18 15:38:12,690 INFO L185 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 18.08 03:38:12" (1/1) ... [2020-08-18 15:38:12,693 INFO L205 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@23d1a539 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:12, skipping insertion in model container [2020-08-18 15:38:12,693 INFO L185 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 18.08 03:38:12" (1/1) ... [2020-08-18 15:38:12,701 INFO L145 MainTranslator]: Starting translation in SV-COMP mode [2020-08-18 15:38:12,887 INFO L178 MainTranslator]: Built tables and reachable declarations [2020-08-18 15:38:14,380 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-08-18 15:38:14,393 INFO L203 MainTranslator]: Completed pre-run [2020-08-18 15:38:15,726 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-08-18 15:38:15,750 INFO L208 MainTranslator]: Completed translation [2020-08-18 15:38:15,751 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:15 WrapperNode [2020-08-18 15:38:15,751 INFO L132 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2020-08-18 15:38:15,752 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2020-08-18 15:38:15,752 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2020-08-18 15:38:15,753 INFO L275 PluginConnector]: Boogie Preprocessor initialized [2020-08-18 15:38:15,768 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:15" (1/1) ... [2020-08-18 15:38:15,768 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:15" (1/1) ... [2020-08-18 15:38:15,802 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:15" (1/1) ... [2020-08-18 15:38:15,803 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:15" (1/1) ... [2020-08-18 15:38:15,877 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:15" (1/1) ... [2020-08-18 15:38:15,919 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:15" (1/1) ... [2020-08-18 15:38:15,936 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:15" (1/1) ... [2020-08-18 15:38:15,963 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2020-08-18 15:38:15,964 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2020-08-18 15:38:15,964 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2020-08-18 15:38:15,965 INFO L275 PluginConnector]: RCFGBuilder initialized [2020-08-18 15:38:15,966 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:15" (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 15:38:16,074 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.init [2020-08-18 15:38:16,075 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2020-08-18 15:38:16,075 INFO L138 BoogieDeclarations]: Found implementation of procedure assume_abort_if_not [2020-08-18 15:38:16,075 INFO L138 BoogieDeclarations]: Found implementation of procedure main [2020-08-18 15:38:16,076 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_error [2020-08-18 15:38:16,076 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_char [2020-08-18 15:38:16,078 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_bool [2020-08-18 15:38:16,078 INFO L130 BoogieDeclarations]: Found specification of procedure assert [2020-08-18 15:38:16,078 INFO L130 BoogieDeclarations]: Found specification of procedure abort [2020-08-18 15:38:16,078 INFO L130 BoogieDeclarations]: Found specification of procedure assume_abort_if_not [2020-08-18 15:38:16,079 INFO L130 BoogieDeclarations]: Found specification of procedure read [2020-08-18 15:38:16,080 INFO L130 BoogieDeclarations]: Found specification of procedure write [2020-08-18 15:38:16,080 INFO L130 BoogieDeclarations]: Found specification of procedure node1 [2020-08-18 15:38:16,080 INFO L130 BoogieDeclarations]: Found specification of procedure node2 [2020-08-18 15:38:16,080 INFO L130 BoogieDeclarations]: Found specification of procedure node3 [2020-08-18 15:38:16,082 INFO L130 BoogieDeclarations]: Found specification of procedure node4 [2020-08-18 15:38:16,082 INFO L130 BoogieDeclarations]: Found specification of procedure node5 [2020-08-18 15:38:16,082 INFO L130 BoogieDeclarations]: Found specification of procedure init [2020-08-18 15:38:16,083 INFO L130 BoogieDeclarations]: Found specification of procedure check [2020-08-18 15:38:16,084 INFO L130 BoogieDeclarations]: Found specification of procedure main [2020-08-18 15:38:16,084 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.init [2020-08-18 15:38:16,084 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2020-08-18 15:38:20,041 INFO L290 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2020-08-18 15:38:20,041 INFO L295 CfgBuilder]: Removed 0 assume(true) statements. [2020-08-18 15:38:20,052 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 18.08 03:38:20 BoogieIcfgContainer [2020-08-18 15:38:20,052 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2020-08-18 15:38:20,054 INFO L113 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2020-08-18 15:38:20,054 INFO L271 PluginConnector]: Initializing TraceAbstraction... [2020-08-18 15:38:20,058 INFO L275 PluginConnector]: TraceAbstraction initialized [2020-08-18 15:38:20,059 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 18.08 03:38:12" (1/3) ... [2020-08-18 15:38:20,059 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@4321e525 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 18.08 03:38:20, skipping insertion in model container [2020-08-18 15:38:20,060 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.08 03:38:15" (2/3) ... [2020-08-18 15:38:20,060 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@4321e525 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 18.08 03:38:20, skipping insertion in model container [2020-08-18 15:38:20,060 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 18.08 03:38:20" (3/3) ... [2020-08-18 15:38:20,062 INFO L109 eAbstractionObserver]: Analyzing ICFG pals_floodmax.5.2.ufo.BOUNDED-10.pals.c.v+lhb-reducer.c [2020-08-18 15:38:20,072 INFO L157 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:Craig_NestedInterpolation Determinization: PREDICATE_ABSTRACTION [2020-08-18 15:38:20,083 INFO L169 ceAbstractionStarter]: Appying trace abstraction to program that has 2 error locations. [2020-08-18 15:38:20,097 INFO L251 AbstractCegarLoop]: Starting to check reachability of 2 error locations. [2020-08-18 15:38:20,129 INFO L375 AbstractCegarLoop]: Interprodecural is true [2020-08-18 15:38:20,129 INFO L376 AbstractCegarLoop]: Hoare is true [2020-08-18 15:38:20,129 INFO L377 AbstractCegarLoop]: Compute interpolants for Craig_NestedInterpolation [2020-08-18 15:38:20,129 INFO L378 AbstractCegarLoop]: Backedges is STRAIGHT_LINE [2020-08-18 15:38:20,129 INFO L379 AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION [2020-08-18 15:38:20,129 INFO L380 AbstractCegarLoop]: Difference is false [2020-08-18 15:38:20,130 INFO L381 AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA [2020-08-18 15:38:20,130 INFO L385 AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce======== [2020-08-18 15:38:20,166 INFO L276 IsEmpty]: Start isEmpty. Operand 1371 states. [2020-08-18 15:38:20,210 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 465 [2020-08-18 15:38:20,211 INFO L414 BasicCegarLoop]: Found error trace [2020-08-18 15:38:20,212 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] [2020-08-18 15:38:20,213 INFO L427 AbstractCegarLoop]: === Iteration 1 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION, mainErr1ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-18 15:38:20,219 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-18 15:38:20,219 INFO L82 PathProgramCache]: Analyzing trace with hash -856462850, now seen corresponding path program 1 times [2020-08-18 15:38:20,228 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-18 15:38:20,228 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [1184830831] [2020-08-18 15:38:20,229 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-18 15:38:22,012 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 15:38:23,325 WARN L193 SmtUtils]: Spent 810.00 ms on a formula simplification that was a NOOP. DAG size: 391 [2020-08-18 15:38:23,328 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-18 15:38:23,336 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 15:38:24,177 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 15:38:24,178 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [1184830831] [2020-08-18 15:38:24,180 INFO L220 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-08-18 15:38:24,181 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2020-08-18 15:38:24,182 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1892381392] [2020-08-18 15:38:24,188 INFO L459 AbstractCegarLoop]: Interpolant automaton has 5 states [2020-08-18 15:38:24,188 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-18 15:38:24,202 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2020-08-18 15:38:24,203 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2020-08-18 15:38:24,206 INFO L87 Difference]: Start difference. First operand 1371 states. Second operand 5 states. [2020-08-18 15:38:39,757 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-08-18 15:38:39,758 INFO L93 Difference]: Finished difference Result 4059 states and 7350 transitions. [2020-08-18 15:38:39,760 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 6 states. [2020-08-18 15:38:39,761 INFO L78 Accepts]: Start accepts. Automaton has 5 states. Word has length 464 [2020-08-18 15:38:39,762 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-08-18 15:38:39,807 INFO L225 Difference]: With dead ends: 4059 [2020-08-18 15:38:39,807 INFO L226 Difference]: Without dead ends: 2697 [2020-08-18 15:38:39,823 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 7 GetRequests, 3 SyntacticMatches, 0 SemanticMatches, 4 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.8s TimeCoverageRelationStatistics Valid=11, Invalid=19, Unknown=0, NotChecked=0, Total=30 [2020-08-18 15:38:39,848 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 2697 states. [2020-08-18 15:38:40,035 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 2697 to 2647. [2020-08-18 15:38:40,037 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 2647 states. [2020-08-18 15:38:40,048 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 2647 states to 2647 states and 4347 transitions. [2020-08-18 15:38:40,050 INFO L78 Accepts]: Start accepts. Automaton has 2647 states and 4347 transitions. Word has length 464 [2020-08-18 15:38:40,052 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-08-18 15:38:40,052 INFO L479 AbstractCegarLoop]: Abstraction has 2647 states and 4347 transitions. [2020-08-18 15:38:40,052 INFO L480 AbstractCegarLoop]: Interpolant automaton has 5 states. [2020-08-18 15:38:40,052 INFO L276 IsEmpty]: Start isEmpty. Operand 2647 states and 4347 transitions. [2020-08-18 15:38:40,068 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 467 [2020-08-18 15:38:40,068 INFO L414 BasicCegarLoop]: Found error trace [2020-08-18 15:38:40,069 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] [2020-08-18 15:38:40,069 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0 [2020-08-18 15:38:40,069 INFO L427 AbstractCegarLoop]: === Iteration 2 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION, mainErr1ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-18 15:38:40,070 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-18 15:38:40,070 INFO L82 PathProgramCache]: Analyzing trace with hash -1286826198, now seen corresponding path program 1 times [2020-08-18 15:38:40,070 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-18 15:38:40,071 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [598902225] [2020-08-18 15:38:40,071 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-18 15:38:40,325 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 15:38:41,813 WARN L193 SmtUtils]: Spent 1.18 s on a formula simplification that was a NOOP. DAG size: 391 [2020-08-18 15:38:41,814 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-18 15:38:41,823 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 15:38:42,277 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 15:38:42,277 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [598902225] [2020-08-18 15:38:42,277 INFO L220 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-08-18 15:38:42,278 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [4] imperfect sequences [] total 4 [2020-08-18 15:38:42,278 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [2114539367] [2020-08-18 15:38:42,280 INFO L459 AbstractCegarLoop]: Interpolant automaton has 4 states [2020-08-18 15:38:42,280 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-18 15:38:42,280 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2020-08-18 15:38:42,281 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2020-08-18 15:38:42,281 INFO L87 Difference]: Start difference. First operand 2647 states and 4347 transitions. Second operand 4 states. [2020-08-18 15:39:00,334 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-08-18 15:39:00,335 INFO L93 Difference]: Finished difference Result 7670 states and 12560 transitions. [2020-08-18 15:39:00,336 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 4 states. [2020-08-18 15:39:00,337 INFO L78 Accepts]: Start accepts. Automaton has 4 states. Word has length 466 [2020-08-18 15:39:00,338 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-08-18 15:39:00,366 INFO L225 Difference]: With dead ends: 7670 [2020-08-18 15:39:00,366 INFO L226 Difference]: Without dead ends: 5237 [2020-08-18 15:39:00,372 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 15:39:00,380 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 5237 states. [2020-08-18 15:39:00,552 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 5237 to 5189. [2020-08-18 15:39:00,552 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 5189 states. [2020-08-18 15:39:00,572 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 5189 states to 5189 states and 8497 transitions. [2020-08-18 15:39:00,574 INFO L78 Accepts]: Start accepts. Automaton has 5189 states and 8497 transitions. Word has length 466 [2020-08-18 15:39:00,575 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-08-18 15:39:00,576 INFO L479 AbstractCegarLoop]: Abstraction has 5189 states and 8497 transitions. [2020-08-18 15:39:00,576 INFO L480 AbstractCegarLoop]: Interpolant automaton has 4 states. [2020-08-18 15:39:00,576 INFO L276 IsEmpty]: Start isEmpty. Operand 5189 states and 8497 transitions. [2020-08-18 15:39:00,599 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 468 [2020-08-18 15:39:00,599 INFO L414 BasicCegarLoop]: Found error trace [2020-08-18 15:39:00,600 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] [2020-08-18 15:39:00,600 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable1 [2020-08-18 15:39:00,600 INFO L427 AbstractCegarLoop]: === Iteration 3 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION, mainErr1ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-18 15:39:00,601 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-18 15:39:00,605 INFO L82 PathProgramCache]: Analyzing trace with hash -244647039, now seen corresponding path program 1 times [2020-08-18 15:39:00,605 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-18 15:39:00,606 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [807898632] [2020-08-18 15:39:00,606 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-18 15:39:00,705 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 15:39:01,682 WARN L193 SmtUtils]: Spent 801.00 ms on a formula simplification that was a NOOP. DAG size: 391 [2020-08-18 15:39:01,683 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-18 15:39:01,691 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-18 15:39:01,890 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 15:39:01,891 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [807898632] [2020-08-18 15:39:01,891 INFO L220 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-08-18 15:39:01,891 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [4] imperfect sequences [] total 4 [2020-08-18 15:39:01,892 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [810670217] [2020-08-18 15:39:01,898 INFO L459 AbstractCegarLoop]: Interpolant automaton has 4 states [2020-08-18 15:39:01,899 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-18 15:39:01,900 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2020-08-18 15:39:01,900 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2020-08-18 15:39:01,900 INFO L87 Difference]: Start difference. First operand 5189 states and 8497 transitions. Second operand 4 states.