/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 -s ../../../trunk/examples/settings/default/automizer/svcomp-Reach-32bit-Automizer_Default.epf -i ../../../trunk/examples/svcomp/loops/n.c11.c -------------------------------------------------------------------------------- This is Ultimate 0.1.25-3af5e1f [2020-09-04 13:43:05,037 INFO L177 SettingsManager]: Resetting all preferences to default values... [2020-09-04 13:43:05,042 INFO L181 SettingsManager]: Resetting UltimateCore preferences to default values [2020-09-04 13:43:05,085 INFO L184 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... [2020-09-04 13:43:05,085 INFO L181 SettingsManager]: Resetting Boogie Preprocessor preferences to default values [2020-09-04 13:43:05,093 INFO L181 SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values [2020-09-04 13:43:05,096 INFO L181 SettingsManager]: Resetting Abstract Interpretation preferences to default values [2020-09-04 13:43:05,100 INFO L181 SettingsManager]: Resetting LassoRanker preferences to default values [2020-09-04 13:43:05,102 INFO L181 SettingsManager]: Resetting Reaching Definitions preferences to default values [2020-09-04 13:43:05,106 INFO L181 SettingsManager]: Resetting SyntaxChecker preferences to default values [2020-09-04 13:43:05,107 INFO L181 SettingsManager]: Resetting Sifa preferences to default values [2020-09-04 13:43:05,108 INFO L184 SettingsManager]: Büchi Program Product provides no preferences, ignoring... [2020-09-04 13:43:05,108 INFO L181 SettingsManager]: Resetting LTL2Aut preferences to default values [2020-09-04 13:43:05,112 INFO L181 SettingsManager]: Resetting PEA to Boogie preferences to default values [2020-09-04 13:43:05,114 INFO L181 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2020-09-04 13:43:05,116 INFO L181 SettingsManager]: Resetting ChcToBoogie preferences to default values [2020-09-04 13:43:05,118 INFO L181 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2020-09-04 13:43:05,119 INFO L181 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2020-09-04 13:43:05,121 INFO L181 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2020-09-04 13:43:05,129 INFO L181 SettingsManager]: Resetting CodeCheck preferences to default values [2020-09-04 13:43:05,131 INFO L181 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2020-09-04 13:43:05,132 INFO L181 SettingsManager]: Resetting RCFGBuilder preferences to default values [2020-09-04 13:43:05,133 INFO L181 SettingsManager]: Resetting Referee preferences to default values [2020-09-04 13:43:05,134 INFO L181 SettingsManager]: Resetting TraceAbstraction preferences to default values [2020-09-04 13:43:05,150 INFO L184 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... 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[2020-09-04 13:43:05,166 INFO L181 SettingsManager]: Resetting SmtParser preferences to default values [2020-09-04 13:43:05,167 INFO L181 SettingsManager]: Resetting Witness Parser preferences to default values [2020-09-04 13:43:05,168 INFO L188 SettingsManager]: Finished resetting all preferences to default values... [2020-09-04 13:43:05,169 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 [2020-09-04 13:43:05,213 INFO L113 SettingsManager]: Loading preferences was successful [2020-09-04 13:43:05,213 INFO L115 SettingsManager]: Preferences different from defaults after loading the file: [2020-09-04 13:43:05,215 INFO L136 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2020-09-04 13:43:05,216 INFO L138 SettingsManager]: * Create parallel compositions if possible=false [2020-09-04 13:43:05,216 INFO L138 SettingsManager]: * Use SBE=true [2020-09-04 13:43:05,216 INFO L136 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2020-09-04 13:43:05,216 INFO L138 SettingsManager]: * sizeof long=4 [2020-09-04 13:43:05,216 INFO L138 SettingsManager]: * Overapproximate operations on floating types=true [2020-09-04 13:43:05,217 INFO L138 SettingsManager]: * sizeof POINTER=4 [2020-09-04 13:43:05,217 INFO L138 SettingsManager]: * Check division by zero=IGNORE [2020-09-04 13:43:05,218 INFO L138 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2020-09-04 13:43:05,218 INFO L138 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2020-09-04 13:43:05,218 INFO L138 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2020-09-04 13:43:05,219 INFO L138 SettingsManager]: * sizeof long double=12 [2020-09-04 13:43:05,219 INFO L138 SettingsManager]: * Check if freed pointer was valid=false [2020-09-04 13:43:05,219 INFO L138 SettingsManager]: * Use constant arrays=true [2020-09-04 13:43:05,219 INFO L138 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2020-09-04 13:43:05,220 INFO L136 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2020-09-04 13:43:05,220 INFO L138 SettingsManager]: * Size of a code block=SequenceOfStatements [2020-09-04 13:43:05,220 INFO L138 SettingsManager]: * To the following directory=./dump/ [2020-09-04 13:43:05,220 INFO L138 SettingsManager]: * SMT solver=External_DefaultMode [2020-09-04 13:43:05,220 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2020-09-04 13:43:05,221 INFO L136 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2020-09-04 13:43:05,221 INFO L138 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2020-09-04 13:43:05,221 INFO L138 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles [2020-09-04 13:43:05,221 INFO L138 SettingsManager]: * Trace refinement strategy=CAMEL [2020-09-04 13:43:05,221 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2020-09-04 13:43:05,222 INFO L138 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2020-09-04 13:43:05,222 INFO L138 SettingsManager]: * Trace refinement exception blacklist=NONE [2020-09-04 13:43:05,222 INFO L138 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2020-09-04 13:43:05,659 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2020-09-04 13:43:05,679 INFO L258 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2020-09-04 13:43:05,683 INFO L214 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2020-09-04 13:43:05,685 INFO L271 PluginConnector]: Initializing CDTParser... [2020-09-04 13:43:05,685 INFO L275 PluginConnector]: CDTParser initialized [2020-09-04 13:43:05,686 INFO L429 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/svcomp/loops/n.c11.c [2020-09-04 13:43:05,775 INFO L220 CDTParser]: Created temporary CDT project at /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/ae36b81b0/c75856e211be4c9e9c0938ca594896db/FLAG5f6b93343 [2020-09-04 13:43:06,311 INFO L306 CDTParser]: Found 1 translation units. [2020-09-04 13:43:06,312 INFO L160 CDTParser]: Scanning /storage/repos/ultimate-2/trunk/examples/svcomp/loops/n.c11.c [2020-09-04 13:43:06,320 INFO L349 CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/ae36b81b0/c75856e211be4c9e9c0938ca594896db/FLAG5f6b93343 [2020-09-04 13:43:06,653 INFO L357 CDTParser]: Successfully deleted /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/ae36b81b0/c75856e211be4c9e9c0938ca594896db [2020-09-04 13:43:06,666 INFO L296 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2020-09-04 13:43:06,669 INFO L131 ToolchainWalker]: Walking toolchain with 4 elements. [2020-09-04 13:43:06,670 INFO L113 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2020-09-04 13:43:06,670 INFO L271 PluginConnector]: Initializing CACSL2BoogieTranslator... [2020-09-04 13:43:06,674 INFO L275 PluginConnector]: CACSL2BoogieTranslator initialized [2020-09-04 13:43:06,675 INFO L185 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 04.09 01:43:06" (1/1) ... [2020-09-04 13:43:06,679 INFO L205 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@7e979d3d and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06, skipping insertion in model container [2020-09-04 13:43:06,680 INFO L185 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 04.09 01:43:06" (1/1) ... [2020-09-04 13:43:06,688 INFO L145 MainTranslator]: Starting translation in SV-COMP mode [2020-09-04 13:43:06,717 INFO L178 MainTranslator]: Built tables and reachable declarations [2020-09-04 13:43:06,937 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-09-04 13:43:06,941 INFO L203 MainTranslator]: Completed pre-run [2020-09-04 13:43:06,957 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-09-04 13:43:06,972 INFO L208 MainTranslator]: Completed translation [2020-09-04 13:43:06,972 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06 WrapperNode [2020-09-04 13:43:06,972 INFO L132 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2020-09-04 13:43:06,973 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2020-09-04 13:43:06,973 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2020-09-04 13:43:06,973 INFO L275 PluginConnector]: Boogie Preprocessor initialized [2020-09-04 13:43:06,986 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06" (1/1) ... [2020-09-04 13:43:06,986 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06" (1/1) ... [2020-09-04 13:43:07,067 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06" (1/1) ... [2020-09-04 13:43:07,068 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06" (1/1) ... [2020-09-04 13:43:07,074 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06" (1/1) ... [2020-09-04 13:43:07,083 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06" (1/1) ... [2020-09-04 13:43:07,086 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06" (1/1) ... [2020-09-04 13:43:07,088 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2020-09-04 13:43:07,088 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2020-09-04 13:43:07,088 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2020-09-04 13:43:07,089 INFO L275 PluginConnector]: RCFGBuilder initialized [2020-09-04 13:43:07,089 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06" (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 [2020-09-04 13:43:07,165 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.init [2020-09-04 13:43:07,165 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2020-09-04 13:43:07,165 INFO L138 BoogieDeclarations]: Found implementation of procedure __VERIFIER_assert [2020-09-04 13:43:07,165 INFO L138 BoogieDeclarations]: Found implementation of procedure main [2020-09-04 13:43:07,165 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_error [2020-09-04 13:43:07,166 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_assert [2020-09-04 13:43:07,166 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_bool [2020-09-04 13:43:07,166 INFO L130 BoogieDeclarations]: Found specification of procedure main [2020-09-04 13:43:07,166 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.init [2020-09-04 13:43:07,166 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2020-09-04 13:43:07,374 INFO L290 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2020-09-04 13:43:07,374 INFO L295 CfgBuilder]: Removed 1 assume(true) statements. [2020-09-04 13:43:07,379 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 04.09 01:43:07 BoogieIcfgContainer [2020-09-04 13:43:07,379 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2020-09-04 13:43:07,380 INFO L113 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2020-09-04 13:43:07,380 INFO L271 PluginConnector]: Initializing TraceAbstraction... [2020-09-04 13:43:07,384 INFO L275 PluginConnector]: TraceAbstraction initialized [2020-09-04 13:43:07,385 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 04.09 01:43:06" (1/3) ... [2020-09-04 13:43:07,385 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@6eec58a4 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 04.09 01:43:07, skipping insertion in model container [2020-09-04 13:43:07,386 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.09 01:43:06" (2/3) ... [2020-09-04 13:43:07,386 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@6eec58a4 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 04.09 01:43:07, skipping insertion in model container [2020-09-04 13:43:07,387 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 04.09 01:43:07" (3/3) ... [2020-09-04 13:43:07,389 INFO L109 eAbstractionObserver]: Analyzing ICFG n.c11.c [2020-09-04 13:43:07,400 INFO L157 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:FPandBP Determinization: PREDICATE_ABSTRACTION [2020-09-04 13:43:07,409 INFO L169 ceAbstractionStarter]: Appying trace abstraction to program that has 1 error locations. [2020-09-04 13:43:07,427 INFO L251 AbstractCegarLoop]: Starting to check reachability of 1 error locations. [2020-09-04 13:43:07,451 INFO L375 AbstractCegarLoop]: Interprodecural is true [2020-09-04 13:43:07,451 INFO L376 AbstractCegarLoop]: Hoare is true [2020-09-04 13:43:07,452 INFO L377 AbstractCegarLoop]: Compute interpolants for FPandBP [2020-09-04 13:43:07,452 INFO L378 AbstractCegarLoop]: Backedges is STRAIGHT_LINE [2020-09-04 13:43:07,452 INFO L379 AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION [2020-09-04 13:43:07,452 INFO L380 AbstractCegarLoop]: Difference is false [2020-09-04 13:43:07,452 INFO L381 AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA [2020-09-04 13:43:07,452 INFO L385 AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce======== [2020-09-04 13:43:07,471 INFO L276 IsEmpty]: Start isEmpty. Operand 20 states. [2020-09-04 13:43:07,477 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 11 [2020-09-04 13:43:07,477 INFO L414 BasicCegarLoop]: Found error trace [2020-09-04 13:43:07,478 INFO L422 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-09-04 13:43:07,479 INFO L427 AbstractCegarLoop]: === Iteration 1 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-09-04 13:43:07,485 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-09-04 13:43:07,485 INFO L82 PathProgramCache]: Analyzing trace with hash -147882559, now seen corresponding path program 1 times [2020-09-04 13:43:07,497 INFO L163 FreeRefinementEngine]: Executing refinement strategy CAMEL [2020-09-04 13:43:07,497 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [63821006] [2020-09-04 13:43:07,497 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-09-04 13:43:07,577 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:07,609 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-09-04 13:43:07,610 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:07,616 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-09-04 13:43:07,617 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [63821006] [2020-09-04 13:43:07,618 INFO L220 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-09-04 13:43:07,618 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [2] imperfect sequences [] total 2 [2020-09-04 13:43:07,619 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [671738659] [2020-09-04 13:43:07,625 INFO L459 AbstractCegarLoop]: Interpolant automaton has 2 states [2020-09-04 13:43:07,626 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2020-09-04 13:43:07,643 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 2 interpolants. [2020-09-04 13:43:07,644 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=1, Invalid=1, Unknown=0, NotChecked=0, Total=2 [2020-09-04 13:43:07,647 INFO L87 Difference]: Start difference. First operand 20 states. Second operand 2 states. [2020-09-04 13:43:07,674 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-09-04 13:43:07,675 INFO L93 Difference]: Finished difference Result 32 states and 36 transitions. [2020-09-04 13:43:07,675 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 2 states. [2020-09-04 13:43:07,677 INFO L78 Accepts]: Start accepts. Automaton has 2 states. Word has length 10 [2020-09-04 13:43:07,677 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-09-04 13:43:07,687 INFO L225 Difference]: With dead ends: 32 [2020-09-04 13:43:07,687 INFO L226 Difference]: Without dead ends: 13 [2020-09-04 13:43:07,691 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 4 GetRequests, 4 SyntacticMatches, 0 SemanticMatches, 0 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=1, Invalid=1, Unknown=0, NotChecked=0, Total=2 [2020-09-04 13:43:07,712 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 13 states. [2020-09-04 13:43:07,733 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 13 to 13. [2020-09-04 13:43:07,734 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 13 states. [2020-09-04 13:43:07,735 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 13 states to 13 states and 14 transitions. [2020-09-04 13:43:07,737 INFO L78 Accepts]: Start accepts. Automaton has 13 states and 14 transitions. Word has length 10 [2020-09-04 13:43:07,737 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-09-04 13:43:07,738 INFO L479 AbstractCegarLoop]: Abstraction has 13 states and 14 transitions. [2020-09-04 13:43:07,738 INFO L480 AbstractCegarLoop]: Interpolant automaton has 2 states. [2020-09-04 13:43:07,738 INFO L276 IsEmpty]: Start isEmpty. Operand 13 states and 14 transitions. [2020-09-04 13:43:07,738 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 11 [2020-09-04 13:43:07,739 INFO L414 BasicCegarLoop]: Found error trace [2020-09-04 13:43:07,739 INFO L422 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-09-04 13:43:07,739 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0 [2020-09-04 13:43:07,740 INFO L427 AbstractCegarLoop]: === Iteration 2 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-09-04 13:43:07,740 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-09-04 13:43:07,740 INFO L82 PathProgramCache]: Analyzing trace with hash -158041290, now seen corresponding path program 1 times [2020-09-04 13:43:07,740 INFO L163 FreeRefinementEngine]: Executing refinement strategy CAMEL [2020-09-04 13:43:07,741 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [851730777] [2020-09-04 13:43:07,741 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-09-04 13:43:07,772 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:07,888 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-09-04 13:43:07,890 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:07,893 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-09-04 13:43:07,894 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [851730777] [2020-09-04 13:43:07,894 INFO L220 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-09-04 13:43:07,894 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2020-09-04 13:43:07,895 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [317248688] [2020-09-04 13:43:07,897 INFO L459 AbstractCegarLoop]: Interpolant automaton has 5 states [2020-09-04 13:43:07,897 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2020-09-04 13:43:07,897 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2020-09-04 13:43:07,898 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2020-09-04 13:43:07,898 INFO L87 Difference]: Start difference. First operand 13 states and 14 transitions. Second operand 5 states. [2020-09-04 13:43:07,961 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-09-04 13:43:07,961 INFO L93 Difference]: Finished difference Result 27 states and 31 transitions. [2020-09-04 13:43:07,962 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2020-09-04 13:43:07,963 INFO L78 Accepts]: Start accepts. Automaton has 5 states. Word has length 10 [2020-09-04 13:43:07,963 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-09-04 13:43:07,964 INFO L225 Difference]: With dead ends: 27 [2020-09-04 13:43:07,964 INFO L226 Difference]: Without dead ends: 16 [2020-09-04 13:43:07,966 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 8 GetRequests, 4 SyntacticMatches, 0 SemanticMatches, 4 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=11, Invalid=19, Unknown=0, NotChecked=0, Total=30 [2020-09-04 13:43:07,966 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 16 states. [2020-09-04 13:43:07,970 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 16 to 15. [2020-09-04 13:43:07,970 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 15 states. [2020-09-04 13:43:07,971 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 15 states to 15 states and 16 transitions. [2020-09-04 13:43:07,972 INFO L78 Accepts]: Start accepts. Automaton has 15 states and 16 transitions. Word has length 10 [2020-09-04 13:43:07,972 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-09-04 13:43:07,972 INFO L479 AbstractCegarLoop]: Abstraction has 15 states and 16 transitions. [2020-09-04 13:43:07,973 INFO L480 AbstractCegarLoop]: Interpolant automaton has 5 states. [2020-09-04 13:43:07,973 INFO L276 IsEmpty]: Start isEmpty. Operand 15 states and 16 transitions. [2020-09-04 13:43:07,974 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 14 [2020-09-04 13:43:07,974 INFO L414 BasicCegarLoop]: Found error trace [2020-09-04 13:43:07,974 INFO L422 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-09-04 13:43:07,974 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable1 [2020-09-04 13:43:07,975 INFO L427 AbstractCegarLoop]: === Iteration 3 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-09-04 13:43:07,975 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-09-04 13:43:07,975 INFO L82 PathProgramCache]: Analyzing trace with hash -1776138601, now seen corresponding path program 1 times [2020-09-04 13:43:07,975 INFO L163 FreeRefinementEngine]: Executing refinement strategy CAMEL [2020-09-04 13:43:07,976 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [292670526] [2020-09-04 13:43:07,976 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-09-04 13:43:08,010 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:08,148 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-09-04 13:43:08,149 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:08,153 INFO L134 CoverageAnalysis]: Checked inductivity of 1 backedges. 0 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-09-04 13:43:08,154 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [292670526] [2020-09-04 13:43:08,154 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1300066682] [2020-09-04 13:43:08,154 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY No working directory specified, using /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/z3 Starting monitored process 2 with z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 2 with z3 -smt2 -in SMTLIB2_COMPLIANT=true [2020-09-04 13:43:08,201 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:08,203 INFO L263 TraceCheckSpWp]: Trace formula consists of 28 conjuncts, 7 conjunts are in the unsatisfiable core [2020-09-04 13:43:08,210 INFO L286 TraceCheckSpWp]: Computing forward predicates... [2020-09-04 13:43:08,311 INFO L603 QuantifierPusher]: Distributing 2 conjuncts over 3 disjuncts [2020-09-04 13:43:08,365 INFO L134 CoverageAnalysis]: Checked inductivity of 1 backedges. 0 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-09-04 13:43:08,366 INFO L220 FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences. [2020-09-04 13:43:08,366 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [6, 6] total 9 [2020-09-04 13:43:08,366 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1080553158] [2020-09-04 13:43:08,367 INFO L459 AbstractCegarLoop]: Interpolant automaton has 9 states [2020-09-04 13:43:08,367 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2020-09-04 13:43:08,368 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 9 interpolants. [2020-09-04 13:43:08,368 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=19, Invalid=53, Unknown=0, NotChecked=0, Total=72 [2020-09-04 13:43:08,368 INFO L87 Difference]: Start difference. First operand 15 states and 16 transitions. Second operand 9 states. [2020-09-04 13:43:08,425 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-09-04 13:43:08,425 INFO L93 Difference]: Finished difference Result 30 states and 34 transitions. [2020-09-04 13:43:08,426 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 6 states. [2020-09-04 13:43:08,426 INFO L78 Accepts]: Start accepts. Automaton has 9 states. Word has length 13 [2020-09-04 13:43:08,426 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-09-04 13:43:08,427 INFO L225 Difference]: With dead ends: 30 [2020-09-04 13:43:08,427 INFO L226 Difference]: Without dead ends: 19 [2020-09-04 13:43:08,428 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 21 GetRequests, 12 SyntacticMatches, 1 SemanticMatches, 8 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 10 ImplicationChecksByTransitivity, 0.1s TimeCoverageRelationStatistics Valid=25, Invalid=65, Unknown=0, NotChecked=0, Total=90 [2020-09-04 13:43:08,429 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 19 states. [2020-09-04 13:43:08,432 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 19 to 18. [2020-09-04 13:43:08,432 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 18 states. [2020-09-04 13:43:08,433 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 18 states to 18 states and 19 transitions. [2020-09-04 13:43:08,433 INFO L78 Accepts]: Start accepts. Automaton has 18 states and 19 transitions. Word has length 13 [2020-09-04 13:43:08,434 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-09-04 13:43:08,434 INFO L479 AbstractCegarLoop]: Abstraction has 18 states and 19 transitions. [2020-09-04 13:43:08,434 INFO L480 AbstractCegarLoop]: Interpolant automaton has 9 states. [2020-09-04 13:43:08,434 INFO L276 IsEmpty]: Start isEmpty. Operand 18 states and 19 transitions. [2020-09-04 13:43:08,435 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 17 [2020-09-04 13:43:08,435 INFO L414 BasicCegarLoop]: Found error trace [2020-09-04 13:43:08,435 INFO L422 BasicCegarLoop]: trace histogram [2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-09-04 13:43:08,636 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 2 z3 -smt2 -in SMTLIB2_COMPLIANT=true,SelfDestructingSolverStorable2 [2020-09-04 13:43:08,636 INFO L427 AbstractCegarLoop]: === Iteration 4 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-09-04 13:43:08,637 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-09-04 13:43:08,637 INFO L82 PathProgramCache]: Analyzing trace with hash 199799702, now seen corresponding path program 2 times [2020-09-04 13:43:08,638 INFO L163 FreeRefinementEngine]: Executing refinement strategy CAMEL [2020-09-04 13:43:08,638 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1676758177] [2020-09-04 13:43:08,638 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-09-04 13:43:08,659 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:08,789 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-09-04 13:43:08,791 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:08,796 INFO L134 CoverageAnalysis]: Checked inductivity of 5 backedges. 0 proven. 5 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-09-04 13:43:08,796 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1676758177] [2020-09-04 13:43:08,800 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [962427558] [2020-09-04 13:43:08,800 INFO L93 rtionOrderModulation]: Changing assertion order to OUTSIDE_LOOP_FIRST1 No working directory specified, using /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/z3 Starting monitored process 3 with z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 3 with z3 -smt2 -in SMTLIB2_COMPLIANT=true [2020-09-04 13:43:08,845 INFO L228 tOrderPrioritization]: Assert order OUTSIDE_LOOP_FIRST1 issued 2 check-sat command(s) [2020-09-04 13:43:08,846 INFO L229 tOrderPrioritization]: Conjunction of SSA is unsat [2020-09-04 13:43:08,847 INFO L263 TraceCheckSpWp]: Trace formula consists of 33 conjuncts, 9 conjunts are in the unsatisfiable core [2020-09-04 13:43:08,848 INFO L286 TraceCheckSpWp]: Computing forward predicates... [2020-09-04 13:43:08,894 INFO L603 QuantifierPusher]: Distributing 2 conjuncts over 3 disjuncts [2020-09-04 13:43:08,951 INFO L134 CoverageAnalysis]: Checked inductivity of 5 backedges. 0 proven. 5 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-09-04 13:43:08,951 INFO L220 FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences. [2020-09-04 13:43:08,951 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [7, 7] total 10 [2020-09-04 13:43:08,952 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1607665913] [2020-09-04 13:43:08,953 INFO L459 AbstractCegarLoop]: Interpolant automaton has 10 states [2020-09-04 13:43:08,953 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2020-09-04 13:43:08,954 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 10 interpolants. [2020-09-04 13:43:08,955 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=22, Invalid=68, Unknown=0, NotChecked=0, Total=90 [2020-09-04 13:43:08,955 INFO L87 Difference]: Start difference. First operand 18 states and 19 transitions. Second operand 10 states. [2020-09-04 13:43:09,059 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-09-04 13:43:09,060 INFO L93 Difference]: Finished difference Result 36 states and 40 transitions. [2020-09-04 13:43:09,062 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 7 states. [2020-09-04 13:43:09,062 INFO L78 Accepts]: Start accepts. Automaton has 10 states. Word has length 16 [2020-09-04 13:43:09,062 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-09-04 13:43:09,063 INFO L225 Difference]: With dead ends: 36 [2020-09-04 13:43:09,063 INFO L226 Difference]: Without dead ends: 22 [2020-09-04 13:43:09,064 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 25 GetRequests, 15 SyntacticMatches, 1 SemanticMatches, 9 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 10 ImplicationChecksByTransitivity, 0.1s TimeCoverageRelationStatistics Valid=28, Invalid=82, Unknown=0, NotChecked=0, Total=110 [2020-09-04 13:43:09,064 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 22 states. [2020-09-04 13:43:09,068 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 22 to 21. [2020-09-04 13:43:09,068 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 21 states. [2020-09-04 13:43:09,069 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 21 states to 21 states and 22 transitions. [2020-09-04 13:43:09,069 INFO L78 Accepts]: Start accepts. Automaton has 21 states and 22 transitions. Word has length 16 [2020-09-04 13:43:09,070 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-09-04 13:43:09,070 INFO L479 AbstractCegarLoop]: Abstraction has 21 states and 22 transitions. [2020-09-04 13:43:09,070 INFO L480 AbstractCegarLoop]: Interpolant automaton has 10 states. [2020-09-04 13:43:09,070 INFO L276 IsEmpty]: Start isEmpty. Operand 21 states and 22 transitions. [2020-09-04 13:43:09,071 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 20 [2020-09-04 13:43:09,071 INFO L414 BasicCegarLoop]: Found error trace [2020-09-04 13:43:09,071 INFO L422 BasicCegarLoop]: trace histogram [3, 3, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-09-04 13:43:09,272 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable3,3 z3 -smt2 -in SMTLIB2_COMPLIANT=true [2020-09-04 13:43:09,273 INFO L427 AbstractCegarLoop]: === Iteration 5 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-09-04 13:43:09,273 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-09-04 13:43:09,274 INFO L82 PathProgramCache]: Analyzing trace with hash -1443974601, now seen corresponding path program 3 times [2020-09-04 13:43:09,274 INFO L163 FreeRefinementEngine]: Executing refinement strategy CAMEL [2020-09-04 13:43:09,275 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [2037992655] [2020-09-04 13:43:09,275 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-09-04 13:43:09,301 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:09,463 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-09-04 13:43:09,464 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:09,467 INFO L134 CoverageAnalysis]: Checked inductivity of 12 backedges. 0 proven. 12 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-09-04 13:43:09,467 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [2037992655] [2020-09-04 13:43:09,467 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [541387159] [2020-09-04 13:43:09,468 INFO L93 rtionOrderModulation]: Changing assertion order to OUTSIDE_LOOP_FIRST2 No working directory specified, using /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/z3 Starting monitored process 4 with z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 4 with z3 -smt2 -in SMTLIB2_COMPLIANT=true [2020-09-04 13:43:09,521 INFO L228 tOrderPrioritization]: Assert order OUTSIDE_LOOP_FIRST2 issued 4 check-sat command(s) [2020-09-04 13:43:09,522 INFO L229 tOrderPrioritization]: Conjunction of SSA is unsat [2020-09-04 13:43:09,523 INFO L263 TraceCheckSpWp]: Trace formula consists of 38 conjuncts, 11 conjunts are in the unsatisfiable core [2020-09-04 13:43:09,524 INFO L286 TraceCheckSpWp]: Computing forward predicates... [2020-09-04 13:43:09,560 INFO L603 QuantifierPusher]: Distributing 2 conjuncts over 3 disjuncts [2020-09-04 13:43:09,607 INFO L134 CoverageAnalysis]: Checked inductivity of 12 backedges. 0 proven. 12 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-09-04 13:43:09,607 INFO L220 FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences. [2020-09-04 13:43:09,608 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [8, 8] total 11 [2020-09-04 13:43:09,608 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1592096427] [2020-09-04 13:43:09,608 INFO L459 AbstractCegarLoop]: Interpolant automaton has 11 states [2020-09-04 13:43:09,609 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2020-09-04 13:43:09,609 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 11 interpolants. [2020-09-04 13:43:09,609 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=25, Invalid=85, Unknown=0, NotChecked=0, Total=110 [2020-09-04 13:43:09,610 INFO L87 Difference]: Start difference. First operand 21 states and 22 transitions. Second operand 11 states. [2020-09-04 13:43:09,711 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-09-04 13:43:09,711 INFO L93 Difference]: Finished difference Result 42 states and 46 transitions. [2020-09-04 13:43:09,711 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 8 states. [2020-09-04 13:43:09,712 INFO L78 Accepts]: Start accepts. Automaton has 11 states. Word has length 19 [2020-09-04 13:43:09,712 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-09-04 13:43:09,713 INFO L225 Difference]: With dead ends: 42 [2020-09-04 13:43:09,713 INFO L226 Difference]: Without dead ends: 25 [2020-09-04 13:43:09,714 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 29 GetRequests, 18 SyntacticMatches, 1 SemanticMatches, 10 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 10 ImplicationChecksByTransitivity, 0.1s TimeCoverageRelationStatistics Valid=31, Invalid=101, Unknown=0, NotChecked=0, Total=132 [2020-09-04 13:43:09,714 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 25 states. [2020-09-04 13:43:09,717 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 25 to 24. [2020-09-04 13:43:09,718 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 24 states. [2020-09-04 13:43:09,719 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 24 states to 24 states and 25 transitions. [2020-09-04 13:43:09,719 INFO L78 Accepts]: Start accepts. Automaton has 24 states and 25 transitions. Word has length 19 [2020-09-04 13:43:09,719 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-09-04 13:43:09,719 INFO L479 AbstractCegarLoop]: Abstraction has 24 states and 25 transitions. [2020-09-04 13:43:09,719 INFO L480 AbstractCegarLoop]: Interpolant automaton has 11 states. [2020-09-04 13:43:09,720 INFO L276 IsEmpty]: Start isEmpty. Operand 24 states and 25 transitions. [2020-09-04 13:43:09,720 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 23 [2020-09-04 13:43:09,720 INFO L414 BasicCegarLoop]: Found error trace [2020-09-04 13:43:09,721 INFO L422 BasicCegarLoop]: trace histogram [4, 4, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-09-04 13:43:09,933 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable4,4 z3 -smt2 -in SMTLIB2_COMPLIANT=true [2020-09-04 13:43:09,934 INFO L427 AbstractCegarLoop]: === Iteration 6 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-09-04 13:43:09,935 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-09-04 13:43:09,935 INFO L82 PathProgramCache]: Analyzing trace with hash 92873718, now seen corresponding path program 4 times [2020-09-04 13:43:09,936 INFO L163 FreeRefinementEngine]: Executing refinement strategy CAMEL [2020-09-04 13:43:09,937 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1098015250] [2020-09-04 13:43:09,937 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-09-04 13:43:09,975 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:10,136 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-09-04 13:43:10,137 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-09-04 13:43:10,139 INFO L134 CoverageAnalysis]: Checked inductivity of 22 backedges. 0 proven. 22 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-09-04 13:43:10,142 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1098015250] [2020-09-04 13:43:10,142 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1693260326] [2020-09-04 13:43:10,142 INFO L93 rtionOrderModulation]: Changing assertion order to TERMS_WITH_SMALL_CONSTANTS_FIRST No working directory specified, using /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/z3 Starting monitored process 5 with z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 5 with z3 -smt2 -in SMTLIB2_COMPLIANT=true [2020-09-04 13:43:10,183 INFO L228 tOrderPrioritization]: Assert order TERMS_WITH_SMALL_CONSTANTS_FIRST issued 0 check-sat command(s) [2020-09-04 13:43:10,183 INFO L229 tOrderPrioritization]: Conjunction of SSA is unsat [2020-09-04 13:43:10,184 INFO L263 TraceCheckSpWp]: Trace formula consists of 43 conjuncts, 13 conjunts are in the unsatisfiable core [2020-09-04 13:43:10,187 INFO L286 TraceCheckSpWp]: Computing forward predicates... [2020-09-04 13:43:10,221 INFO L603 QuantifierPusher]: Distributing 2 conjuncts over 3 disjuncts [2020-09-04 13:43:10,262 INFO L134 CoverageAnalysis]: Checked inductivity of 22 backedges. 0 proven. 22 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-09-04 13:43:10,262 INFO L220 FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences. [2020-09-04 13:43:10,263 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [9, 9] total 12 [2020-09-04 13:43:10,263 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1306708694] [2020-09-04 13:43:10,264 INFO L459 AbstractCegarLoop]: Interpolant automaton has 12 states [2020-09-04 13:43:10,264 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2020-09-04 13:43:10,264 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 12 interpolants. [2020-09-04 13:43:10,265 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=28, Invalid=104, Unknown=0, NotChecked=0, Total=132 [2020-09-04 13:43:10,266 INFO L87 Difference]: Start difference. First operand 24 states and 25 transitions. Second operand 12 states. [2020-09-04 13:43:10,367 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-09-04 13:43:10,368 INFO L93 Difference]: Finished difference Result 39 states and 42 transitions. [2020-09-04 13:43:10,368 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 9 states. [2020-09-04 13:43:10,368 INFO L78 Accepts]: Start accepts. Automaton has 12 states. Word has length 22 [2020-09-04 13:43:10,368 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-09-04 13:43:10,369 INFO L225 Difference]: With dead ends: 39 [2020-09-04 13:43:10,369 INFO L226 Difference]: Without dead ends: 0 [2020-09-04 13:43:10,370 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 33 GetRequests, 21 SyntacticMatches, 1 SemanticMatches, 11 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 10 ImplicationChecksByTransitivity, 0.1s TimeCoverageRelationStatistics Valid=34, Invalid=122, Unknown=0, NotChecked=0, Total=156 [2020-09-04 13:43:10,370 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 0 states. [2020-09-04 13:43:10,370 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 0 to 0. [2020-09-04 13:43:10,370 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 0 states. [2020-09-04 13:43:10,371 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 0 states to 0 states and 0 transitions. [2020-09-04 13:43:10,371 INFO L78 Accepts]: Start accepts. Automaton has 0 states and 0 transitions. Word has length 22 [2020-09-04 13:43:10,371 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-09-04 13:43:10,371 INFO L479 AbstractCegarLoop]: Abstraction has 0 states and 0 transitions. [2020-09-04 13:43:10,371 INFO L480 AbstractCegarLoop]: Interpolant automaton has 12 states. [2020-09-04 13:43:10,371 INFO L276 IsEmpty]: Start isEmpty. Operand 0 states and 0 transitions. [2020-09-04 13:43:10,372 INFO L282 IsEmpty]: Finished isEmpty. No accepting run. [2020-09-04 13:43:10,580 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable5,5 z3 -smt2 -in SMTLIB2_COMPLIANT=true [2020-09-04 13:43:10,584 INFO L343 DoubleDeckerVisitor]: Before removal of dead ends 0 states and 0 transitions. [2020-09-04 13:43:10,676 INFO L271 CegarLoopResult]: At program point ULTIMATE.initFINAL(line -1) the Hoare annotation is: true [2020-09-04 13:43:10,677 INFO L268 CegarLoopResult]: For program point ULTIMATE.initEXIT(line -1) no Hoare annotation was computed. [2020-09-04 13:43:10,677 INFO L268 CegarLoopResult]: For program point ULTIMATE.startEXIT(line -1) no Hoare annotation was computed. [2020-09-04 13:43:10,677 INFO L271 CegarLoopResult]: At program point L-1(line -1) the Hoare annotation is: true [2020-09-04 13:43:10,677 INFO L271 CegarLoopResult]: At program point ULTIMATE.startENTRY(line -1) the Hoare annotation is: true [2020-09-04 13:43:10,677 INFO L268 CegarLoopResult]: For program point ULTIMATE.startFINAL(line -1) no Hoare annotation was computed. [2020-09-04 13:43:10,678 INFO L271 CegarLoopResult]: At program point mainENTRY(lines 12 32) the Hoare annotation is: true [2020-09-04 13:43:10,678 INFO L268 CegarLoopResult]: For program point L28(line 28) no Hoare annotation was computed. [2020-09-04 13:43:10,678 INFO L268 CegarLoopResult]: For program point mainEXIT(lines 12 32) no Hoare annotation was computed. [2020-09-04 13:43:10,678 INFO L268 CegarLoopResult]: For program point L21(lines 21 22) no Hoare annotation was computed. [2020-09-04 13:43:10,678 INFO L268 CegarLoopResult]: For program point L21-2(lines 21 22) no Hoare annotation was computed. [2020-09-04 13:43:10,679 INFO L264 CegarLoopResult]: At program point L19-2(lines 19 27) the Hoare annotation is: (or (and (<= main_~len~0 1) (<= 1 main_~len~0)) (and (<= 4 main_~len~0) (<= main_~len~0 4)) (and (<= main_~len~0 2) (<= 2 main_~len~0)) (and (<= main_~len~0 0) (<= 0 main_~len~0)) (and (<= main_~len~0 3) (<= 3 main_~len~0))) [2020-09-04 13:43:10,679 INFO L264 CegarLoopResult]: At program point L19-3(lines 19 27) the Hoare annotation is: (or (and (<= main_~len~0 1) (<= 1 main_~len~0)) (and (<= 4 main_~len~0) (<= main_~len~0 4)) (and (<= main_~len~0 2) (<= 2 main_~len~0)) (and (<= main_~len~0 3) (<= 3 main_~len~0)) (and (<= main_~len~0 0) (<= 0 main_~len~0))) [2020-09-04 13:43:10,679 INFO L268 CegarLoopResult]: For program point mainFINAL(lines 12 32) no Hoare annotation was computed. [2020-09-04 13:43:10,679 INFO L271 CegarLoopResult]: At program point __VERIFIER_assertENTRY(lines 3 8) the Hoare annotation is: true [2020-09-04 13:43:10,679 INFO L268 CegarLoopResult]: For program point __VERIFIER_assertEXIT(lines 3 8) no Hoare annotation was computed. [2020-09-04 13:43:10,680 INFO L268 CegarLoopResult]: For program point L5(line 5) no Hoare annotation was computed. [2020-09-04 13:43:10,680 INFO L268 CegarLoopResult]: For program point L4(lines 4 6) no Hoare annotation was computed. [2020-09-04 13:43:10,680 INFO L268 CegarLoopResult]: For program point __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION(line 5) no Hoare annotation was computed. [2020-09-04 13:43:10,680 INFO L268 CegarLoopResult]: For program point L4-2(lines 3 8) no Hoare annotation was computed. [2020-09-04 13:43:10,700 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction CFG 04.09 01:43:10 BoogieIcfgContainer [2020-09-04 13:43:10,700 INFO L132 PluginConnector]: ------------------------ END TraceAbstraction---------------------------- [2020-09-04 13:43:10,704 INFO L168 Benchmark]: Toolchain (without parser) took 4034.53 ms. Allocated memory was 140.5 MB in the beginning and 235.4 MB in the end (delta: 94.9 MB). Free memory was 102.4 MB in the beginning and 104.8 MB in the end (delta: -2.4 MB). Peak memory consumption was 92.5 MB. Max. memory is 7.1 GB. [2020-09-04 13:43:10,705 INFO L168 Benchmark]: CDTParser took 0.25 ms. Allocated memory is still 140.5 MB. Free memory was 120.8 MB in the beginning and 120.6 MB in the end (delta: 209.8 kB). There was no memory consumed. Max. memory is 7.1 GB. [2020-09-04 13:43:10,706 INFO L168 Benchmark]: CACSL2BoogieTranslator took 303.14 ms. Allocated memory is still 140.5 MB. Free memory was 102.2 MB in the beginning and 92.2 MB in the end (delta: 10.0 MB). Peak memory consumption was 10.0 MB. Max. memory is 7.1 GB. [2020-09-04 13:43:10,707 INFO L168 Benchmark]: Boogie Preprocessor took 114.64 ms. Allocated memory was 140.5 MB in the beginning and 203.4 MB in the end (delta: 62.9 MB). Free memory was 92.2 MB in the beginning and 182.2 MB in the end (delta: -90.0 MB). Peak memory consumption was 12.8 MB. Max. memory is 7.1 GB. [2020-09-04 13:43:10,708 INFO L168 Benchmark]: RCFGBuilder took 290.86 ms. Allocated memory is still 203.4 MB. Free memory was 181.6 MB in the beginning and 170.2 MB in the end (delta: 11.3 MB). Peak memory consumption was 11.3 MB. Max. memory is 7.1 GB. [2020-09-04 13:43:10,709 INFO L168 Benchmark]: TraceAbstraction took 3320.43 ms. Allocated memory was 203.4 MB in the beginning and 235.4 MB in the end (delta: 32.0 MB). Free memory was 169.6 MB in the beginning and 104.8 MB in the end (delta: 64.8 MB). Peak memory consumption was 96.8 MB. Max. memory is 7.1 GB. [2020-09-04 13:43:10,713 INFO L336 ainManager$Toolchain]: ####################### End [Toolchain 1] ####################### --- Results --- * Results from de.uni_freiburg.informatik.ultimate.core: - StatisticsResult: Toolchain Benchmarks Benchmark results are: * CDTParser took 0.25 ms. Allocated memory is still 140.5 MB. Free memory was 120.8 MB in the beginning and 120.6 MB in the end (delta: 209.8 kB). There was no memory consumed. Max. memory is 7.1 GB. * CACSL2BoogieTranslator took 303.14 ms. Allocated memory is still 140.5 MB. Free memory was 102.2 MB in the beginning and 92.2 MB in the end (delta: 10.0 MB). Peak memory consumption was 10.0 MB. Max. memory is 7.1 GB. * Boogie Preprocessor took 114.64 ms. Allocated memory was 140.5 MB in the beginning and 203.4 MB in the end (delta: 62.9 MB). Free memory was 92.2 MB in the beginning and 182.2 MB in the end (delta: -90.0 MB). Peak memory consumption was 12.8 MB. Max. memory is 7.1 GB. * RCFGBuilder took 290.86 ms. Allocated memory is still 203.4 MB. Free memory was 181.6 MB in the beginning and 170.2 MB in the end (delta: 11.3 MB). Peak memory consumption was 11.3 MB. Max. memory is 7.1 GB. * TraceAbstraction took 3320.43 ms. Allocated memory was 203.4 MB in the beginning and 235.4 MB in the end (delta: 32.0 MB). Free memory was 169.6 MB in the beginning and 104.8 MB in the end (delta: 64.8 MB). Peak memory consumption was 96.8 MB. Max. memory is 7.1 GB. * Results from de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: - PositiveResult [Line: 5]: call of __VERIFIER_error() unreachable For all program executions holds that call of __VERIFIER_error() unreachable at this location - AllSpecificationsHoldResult: All specifications hold 1 specifications checked. All of them hold - InvariantResult [Line: 19]: Loop Invariant Derived loop invariant: ((((len <= 1 && 1 <= len) || (4 <= len && len <= 4)) || (len <= 2 && 2 <= len)) || (len <= 0 && 0 <= len)) || (len <= 3 && 3 <= len) - StatisticsResult: Ultimate Automizer benchmark data CFG has 4 procedures, 20 locations, 1 error locations. Started 1 CEGAR loops. VerificationResult: SAFE, OverallTime: 3.1s, OverallIterations: 6, TraceHistogramMax: 4, AutomataDifference: 0.5s, DeadEndRemovalTime: 0.0s, HoareAnnotationTime: 0.0s, InitialAbstractionConstructionTime: 0.0s, HoareTripleCheckerStatistics: 83 SDtfs, 37 SDslu, 332 SDs, 0 SdLazy, 264 SolverSat, 21 SolverUnsat, 0 SolverUnknown, 0 SolverNotchecked, 0.2s Time, PredicateUnifierStatistics: 0 DeclaredPredicates, 120 GetRequests, 74 SyntacticMatches, 4 SemanticMatches, 42 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 40 ImplicationChecksByTransitivity, 0.6s Time, 0.0s BasicInterpolantAutomatonTime, BiggestAbstraction: size=24occurred in iteration=5, traceCheckStatistics: No data available, InterpolantConsolidationStatistics: No data available, PathInvariantsStatistics: No data available, 0/0 InterpolantCoveringCapability, TotalInterpolationStatistics: No data available, 0.0s DumpTime, AutomataMinimizationStatistics: 0.0s AutomataMinimizationTime, 6 MinimizatonAttempts, 4 StatesRemovedByMinimization, 4 NontrivialMinimizations, HoareAnnotationStatistics: 0.0s HoareAnnotationTime, 7 LocationsWithAnnotation, 17 PreInvPairs, 27 NumberOfFragments, 77 HoareAnnotationTreeSize, 17 FomulaSimplifications, 0 FormulaSimplificationTreeSizeReduction, 0.0s HoareSimplificationTime, 7 FomulaSimplificationsInter, 0 FormulaSimplificationTreeSizeReductionInter, 0.0s HoareSimplificationTimeInter, RefinementEngineStatistics: TRACE_CHECK: 0.0s SsaConstructionTime, 0.2s SatisfiabilityAnalysisTime, 1.1s InterpolantComputationTime, 160 NumberOfCodeBlocks, 160 NumberOfCodeBlocksAsserted, 15 NumberOfCheckSat, 150 ConstructedInterpolants, 0 QuantifiedInterpolants, 11844 SizeOfPredicates, 8 NumberOfNonLiveVariables, 142 ConjunctsInSsa, 40 ConjunctsInUnsatCore, 10 InterpolantComputations, 2 PerfectInterpolantSequences, 0/80 InterpolantCoveringCapability, INVARIANT_SYNTHESIS: No data available, INTERPOLANT_CONSOLIDATION: No data available, ABSTRACT_INTERPRETATION: No data available, PDR: No data available, ACCELERATED_INTERPOLATION: No data available, SIFA: No data available, ReuseStatistics: No data available RESULT: Ultimate proved your program to be correct! Received shutdown request...