./Ultimate.py --spec ../../sv-benchmarks/c/properties/unreach-call.prp --file ../../sv-benchmarks/c/nla-digbench-scaling/hard2_unwindbound20.c --full-output --architecture 32bit -------------------------------------------------------------------------------- Checking for ERROR reachability Using default analysis Version 30e01a73 Calling Ultimate with: /usr/lib/jvm/java-1.11.0-openjdk-amd64/bin/java -Dosgi.configuration.area=/tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/data/config -Xmx15G -Xms4m -jar /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/plugins/org.eclipse.equinox.launcher_1.5.800.v20200727-1323.jar -data @noDefault -ultimatedata /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/data -tc /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/config/TaipanReach.xml -i ../../sv-benchmarks/c/nla-digbench-scaling/hard2_unwindbound20.c -s /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/config/svcomp-Reach-32bit-Taipan_Default.epf --cacsl2boogietranslator.entry.function main --witnessprinter.witness.directory /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire --witnessprinter.witness.filename witness --witnessprinter.write.witness.besides.input.file false --witnessprinter.graph.data.specification CHECK( init(main()), LTL(G ! call(reach_error())) ) --witnessprinter.graph.data.producer Taipan --witnessprinter.graph.data.architecture 32bit --witnessprinter.graph.data.programhash b0dc7e6cdf006545b97e616af165994b39a2e54c024b52d6607380c5e84ee914 --- Real Ultimate output --- This is Ultimate 0.2.3-dev-30e01a7 [2023-11-23 21:24:27,360 INFO L188 SettingsManager]: Resetting all preferences to default values... [2023-11-23 21:24:27,501 INFO L114 SettingsManager]: Loading settings from /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/config/svcomp-Reach-32bit-Taipan_Default.epf [2023-11-23 21:24:27,513 WARN L101 SettingsManager]: Preference file contains the following unknown settings: [2023-11-23 21:24:27,514 WARN L103 SettingsManager]: * de.uni_freiburg.informatik.ultimate.core.Log level for class [2023-11-23 21:24:27,561 INFO L130 SettingsManager]: Preferences different from defaults after loading the file: [2023-11-23 21:24:27,562 INFO L151 SettingsManager]: Preferences of UltimateCore differ from their defaults: [2023-11-23 21:24:27,563 INFO L153 SettingsManager]: * Log level for class=de.uni_freiburg.informatik.ultimate.lib.smtlibutils.quantifier.QuantifierPusher=ERROR; [2023-11-23 21:24:27,564 INFO L151 SettingsManager]: Preferences of Boogie Procedure Inliner differ from their defaults: [2023-11-23 21:24:27,570 INFO L153 SettingsManager]: * Ignore calls to procedures called more than once=ONLY_FOR_SEQUENTIAL_PROGRAMS [2023-11-23 21:24:27,571 INFO L153 SettingsManager]: * User list type=DISABLED [2023-11-23 21:24:27,571 INFO L151 SettingsManager]: Preferences of Abstract Interpretation differ from their defaults: [2023-11-23 21:24:27,572 INFO L153 SettingsManager]: * Explicit value domain=true [2023-11-23 21:24:27,574 INFO L153 SettingsManager]: * Abstract domain for RCFG-of-the-future=PoormanAbstractDomain [2023-11-23 21:24:27,575 INFO L153 SettingsManager]: * Octagon Domain=false [2023-11-23 21:24:27,575 INFO L153 SettingsManager]: * Abstract domain=CompoundDomain [2023-11-23 21:24:27,576 INFO L153 SettingsManager]: * Check feasibility of abstract posts with an SMT solver=true [2023-11-23 21:24:27,576 INFO L153 SettingsManager]: * Use the RCFG-of-the-future interface=true [2023-11-23 21:24:27,577 INFO L153 SettingsManager]: * Interval Domain=false [2023-11-23 21:24:27,577 INFO L151 SettingsManager]: Preferences of Sifa differ from their defaults: [2023-11-23 21:24:27,578 INFO L153 SettingsManager]: * Call Summarizer=TopInputCallSummarizer [2023-11-23 21:24:27,579 INFO L153 SettingsManager]: * Simplification Technique=POLY_PAC [2023-11-23 21:24:27,580 INFO L151 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2023-11-23 21:24:27,581 INFO L153 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2023-11-23 21:24:27,581 INFO L153 SettingsManager]: * sizeof long=4 [2023-11-23 21:24:27,582 INFO L153 SettingsManager]: * Overapproximate operations on floating types=true [2023-11-23 21:24:27,582 INFO L153 SettingsManager]: * sizeof POINTER=4 [2023-11-23 21:24:27,583 INFO L153 SettingsManager]: * Check division by zero=IGNORE [2023-11-23 21:24:27,583 INFO L153 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2023-11-23 21:24:27,584 INFO L153 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2023-11-23 21:24:27,586 INFO L153 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2023-11-23 21:24:27,586 INFO L153 SettingsManager]: * sizeof long double=12 [2023-11-23 21:24:27,586 INFO L153 SettingsManager]: * Check if freed pointer was valid=false [2023-11-23 21:24:27,586 INFO L153 SettingsManager]: * Use constant arrays=true [2023-11-23 21:24:27,587 INFO L151 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2023-11-23 21:24:27,587 INFO L153 SettingsManager]: * Only consider context switches at boundaries of atomic blocks=true [2023-11-23 21:24:27,588 INFO L153 SettingsManager]: * SMT solver=External_DefaultMode [2023-11-23 21:24:27,589 INFO L153 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2023-11-23 21:24:27,589 INFO L151 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2023-11-23 21:24:27,589 INFO L153 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2023-11-23 21:24:27,590 INFO L153 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopHeads [2023-11-23 21:24:27,590 INFO L153 SettingsManager]: * Trace refinement strategy=SIFA_TAIPAN [2023-11-23 21:24:27,590 INFO L153 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2023-11-23 21:24:27,591 INFO L153 SettingsManager]: * Apply one-shot large block encoding in concurrent analysis=false [2023-11-23 21:24:27,591 INFO L153 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2023-11-23 21:24:27,592 INFO L153 SettingsManager]: * Trace refinement exception blacklist=NONE [2023-11-23 21:24:27,592 INFO L153 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2023-11-23 21:24:27,592 INFO L153 SettingsManager]: * Abstract interpretation Mode=USE_PREDICATES WARNING: An illegal reflective access operation has occurred WARNING: Illegal reflective access by com.sun.xml.bind.v2.runtime.reflect.opt.Injector$1 (file:/tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/plugins/com.sun.xml.bind_2.2.0.v201505121915.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int) WARNING: Please consider reporting this to the maintainers of com.sun.xml.bind.v2.runtime.reflect.opt.Injector$1 WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations WARNING: All illegal access operations will be denied in a future release Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator: Entry function -> main Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness directory -> /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness filename -> witness Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Write witness besides input file -> false Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data specification -> CHECK( init(main()), LTL(G ! call(reach_error())) ) Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data producer -> Taipan Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data architecture -> 32bit Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data programhash -> b0dc7e6cdf006545b97e616af165994b39a2e54c024b52d6607380c5e84ee914 [2023-11-23 21:24:27,975 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2023-11-23 21:24:28,016 INFO L261 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2023-11-23 21:24:28,020 INFO L217 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2023-11-23 21:24:28,023 INFO L270 PluginConnector]: Initializing CDTParser... [2023-11-23 21:24:28,024 INFO L274 PluginConnector]: CDTParser initialized [2023-11-23 21:24:28,025 INFO L431 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/../../sv-benchmarks/c/nla-digbench-scaling/hard2_unwindbound20.c [2023-11-23 21:24:31,308 INFO L533 CDTParser]: Created temporary CDT project at NULL [2023-11-23 21:24:31,601 INFO L384 CDTParser]: Found 1 translation units. [2023-11-23 21:24:31,602 INFO L180 CDTParser]: Scanning /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/sv-benchmarks/c/nla-digbench-scaling/hard2_unwindbound20.c [2023-11-23 21:24:31,611 INFO L427 CDTParser]: About to delete temporary CDT project at /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/data/657219ba7/18a967b72e204e25ab0e0b6b6b3c9620/FLAG08cc749a1 [2023-11-23 21:24:31,629 INFO L435 CDTParser]: Successfully deleted /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/data/657219ba7/18a967b72e204e25ab0e0b6b6b3c9620 [2023-11-23 21:24:31,632 INFO L299 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2023-11-23 21:24:31,634 INFO L133 ToolchainWalker]: Walking toolchain with 6 elements. [2023-11-23 21:24:31,636 INFO L112 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2023-11-23 21:24:31,637 INFO L270 PluginConnector]: Initializing CACSL2BoogieTranslator... [2023-11-23 21:24:31,644 INFO L274 PluginConnector]: CACSL2BoogieTranslator initialized [2023-11-23 21:24:31,645 INFO L184 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 23.11 09:24:31" (1/1) ... [2023-11-23 21:24:31,646 INFO L204 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@76c9017 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:31, skipping insertion in model container [2023-11-23 21:24:31,647 INFO L184 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 23.11 09:24:31" (1/1) ... [2023-11-23 21:24:31,674 INFO L177 MainTranslator]: Built tables and reachable declarations [2023-11-23 21:24:31,959 WARN L240 ndardFunctionHandler]: Function reach_error is already implemented but we override the implementation for the call at /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/sv-benchmarks/c/nla-digbench-scaling/hard2_unwindbound20.c[526,539] [2023-11-23 21:24:31,992 INFO L209 PostProcessor]: Analyzing one entry point: main [2023-11-23 21:24:32,010 INFO L202 MainTranslator]: Completed pre-run [2023-11-23 21:24:32,027 WARN L240 ndardFunctionHandler]: Function reach_error is already implemented but we override the implementation for the call at /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/sv-benchmarks/c/nla-digbench-scaling/hard2_unwindbound20.c[526,539] [2023-11-23 21:24:32,035 INFO L209 PostProcessor]: Analyzing one entry point: main [2023-11-23 21:24:32,055 INFO L206 MainTranslator]: Completed translation [2023-11-23 21:24:32,055 INFO L201 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32 WrapperNode [2023-11-23 21:24:32,056 INFO L131 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2023-11-23 21:24:32,057 INFO L112 PluginConnector]: ------------------------Boogie Procedure Inliner---------------------------- [2023-11-23 21:24:32,057 INFO L270 PluginConnector]: Initializing Boogie Procedure Inliner... [2023-11-23 21:24:32,058 INFO L274 PluginConnector]: Boogie Procedure Inliner initialized [2023-11-23 21:24:32,067 INFO L184 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,077 INFO L184 PluginConnector]: Executing the observer Inliner from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,097 INFO L138 Inliner]: procedures = 14, calls = 22, calls flagged for inlining = 2, calls inlined = 2, statements flattened = 69 [2023-11-23 21:24:32,098 INFO L131 PluginConnector]: ------------------------ END Boogie Procedure Inliner---------------------------- [2023-11-23 21:24:32,099 INFO L112 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2023-11-23 21:24:32,099 INFO L270 PluginConnector]: Initializing Boogie Preprocessor... [2023-11-23 21:24:32,099 INFO L274 PluginConnector]: Boogie Preprocessor initialized [2023-11-23 21:24:32,109 INFO L184 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,110 INFO L184 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,111 INFO L184 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,112 INFO L184 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,116 INFO L184 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,120 INFO L184 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,136 INFO L184 PluginConnector]: Executing the observer LTLStepAnnotator from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,137 INFO L184 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,139 INFO L131 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2023-11-23 21:24:32,140 INFO L112 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2023-11-23 21:24:32,141 INFO L270 PluginConnector]: Initializing RCFGBuilder... [2023-11-23 21:24:32,141 INFO L274 PluginConnector]: RCFGBuilder initialized [2023-11-23 21:24:32,142 INFO L184 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (1/1) ... [2023-11-23 21:24:32,151 INFO L173 SolverBuilder]: Constructing external solver with command: z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2023-11-23 21:24:32,170 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:32,185 INFO L229 MonitoredProcess]: Starting monitored process 1 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (exit command is (exit), workingDir is null) [2023-11-23 21:24:32,219 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (1)] Waiting until timeout for monitored process [2023-11-23 21:24:32,236 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.allocInit [2023-11-23 21:24:32,237 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~int [2023-11-23 21:24:32,237 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2023-11-23 21:24:32,237 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2023-11-23 21:24:32,239 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_assert [2023-11-23 21:24:32,240 INFO L138 BoogieDeclarations]: Found implementation of procedure __VERIFIER_assert [2023-11-23 21:24:32,322 INFO L241 CfgBuilder]: Building ICFG [2023-11-23 21:24:32,325 INFO L267 CfgBuilder]: Building CFG for each procedure with an implementation [2023-11-23 21:24:32,516 INFO L282 CfgBuilder]: Performing block encoding [2023-11-23 21:24:32,574 INFO L304 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2023-11-23 21:24:32,574 INFO L309 CfgBuilder]: Removed 2 assume(true) statements. [2023-11-23 21:24:32,576 INFO L201 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 23.11 09:24:32 BoogieIcfgContainer [2023-11-23 21:24:32,576 INFO L131 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2023-11-23 21:24:32,579 INFO L112 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2023-11-23 21:24:32,579 INFO L270 PluginConnector]: Initializing TraceAbstraction... [2023-11-23 21:24:32,584 INFO L274 PluginConnector]: TraceAbstraction initialized [2023-11-23 21:24:32,584 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 23.11 09:24:31" (1/3) ... [2023-11-23 21:24:32,586 INFO L204 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@24d37bbb and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 23.11 09:24:32, skipping insertion in model container [2023-11-23 21:24:32,586 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 23.11 09:24:32" (2/3) ... [2023-11-23 21:24:32,587 INFO L204 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@24d37bbb and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 23.11 09:24:32, skipping insertion in model container [2023-11-23 21:24:32,587 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 23.11 09:24:32" (3/3) ... [2023-11-23 21:24:32,588 INFO L112 eAbstractionObserver]: Analyzing ICFG hard2_unwindbound20.c [2023-11-23 21:24:32,613 INFO L203 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:FPandBP Determinization: PREDICATE_ABSTRACTION [2023-11-23 21:24:32,615 INFO L162 ceAbstractionStarter]: Applying trace abstraction to program that has 1 error locations. [2023-11-23 21:24:32,722 INFO L356 AbstractCegarLoop]: ======== Iteration 0 == of CEGAR loop == AllErrorsAtOnce ======== [2023-11-23 21:24:32,735 INFO L357 AbstractCegarLoop]: Settings: SEPARATE_VIOLATION_CHECK=true, mInterprocedural=true, mMaxIterations=1000000, mWatchIteration=1000000, mArtifact=RCFG, mInterpolation=FPandBP, mInterpolantAutomaton=STRAIGHT_LINE, mDumpAutomata=false, mAutomataFormat=ATS_NUMERATE, mDumpPath=., mDeterminiation=PREDICATE_ABSTRACTION, mMinimize=MINIMIZE_SEVPA, mHoare=true, mAutomataTypeConcurrency=FINITE_AUTOMATA, mHoareTripleChecks=INCREMENTAL, mHoareAnnotationPositions=LoopHeads, mDumpOnlyReuseAutomata=false, mLimitTraceHistogram=0, mErrorLocTimeLimit=0, mLimitPathProgramCount=0, mCollectInterpolantStatistics=true, mHeuristicEmptinessCheck=false, mHeuristicEmptinessCheckAStarHeuristic=ZERO, mHeuristicEmptinessCheckAStarHeuristicRandomSeed=1337, mHeuristicEmptinessCheckSmtFeatureScoringMethod=DAGSIZE, mSMTFeatureExtraction=false, mSMTFeatureExtractionDumpPath=., mOverrideInterpolantAutomaton=false, mMcrInterpolantMethod=WP, mPorIndependenceSettings=[Lde.uni_freiburg.informatik.ultimate.lib.tracecheckerutils.partialorder.independence.IndependenceSettings;@3cd071c8, mLbeIndependenceSettings=[IndependenceType=SEMANTIC, AbstractionType=NONE, UseConditional=false, UseSemiCommutativity=true, Solver=Z3, SolverTimeout=1000ms] [2023-11-23 21:24:32,737 INFO L358 AbstractCegarLoop]: Starting to check reachability of 1 error locations. [2023-11-23 21:24:32,743 INFO L276 IsEmpty]: Start isEmpty. Operand has 22 states, 12 states have (on average 1.6666666666666667) internal successors, (20), 13 states have internal predecessors, (20), 7 states have call successors, (7), 1 states have call predecessors, (7), 1 states have return successors, (7), 7 states have call predecessors, (7), 7 states have call successors, (7) [2023-11-23 21:24:32,753 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 8 [2023-11-23 21:24:32,754 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:32,756 INFO L195 NwaCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:32,757 INFO L420 AbstractCegarLoop]: === Iteration 1 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:32,767 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:32,767 INFO L85 PathProgramCache]: Analyzing trace with hash 1291730102, now seen corresponding path program 1 times [2023-11-23 21:24:32,782 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:32,783 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1616463679] [2023-11-23 21:24:32,785 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:32,786 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:32,942 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:32,973 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:32,973 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1616463679] [2023-11-23 21:24:32,974 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: Unsupported non-linear arithmetic [2023-11-23 21:24:32,975 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [2098478120] [2023-11-23 21:24:32,975 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:32,975 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:32,976 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:32,978 INFO L229 MonitoredProcess]: Starting monitored process 2 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:24:32,988 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (2)] Waiting until timeout for monitored process [2023-11-23 21:24:33,060 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:33,062 INFO L262 TraceCheckSpWp]: Trace formula consists of 62 conjuncts, 1 conjunts are in the unsatisfiable core [2023-11-23 21:24:33,067 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:24:33,094 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2023-11-23 21:24:33,094 INFO L323 TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect [2023-11-23 21:24:33,096 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [2098478120] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-23 21:24:33,096 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-23 21:24:33,096 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [2] imperfect sequences [] total 2 [2023-11-23 21:24:33,099 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [553799658] [2023-11-23 21:24:33,101 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-23 21:24:33,107 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 2 states [2023-11-23 21:24:33,107 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:33,144 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 2 interpolants. [2023-11-23 21:24:33,145 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=1, Invalid=1, Unknown=0, NotChecked=0, Total=2 [2023-11-23 21:24:33,148 INFO L87 Difference]: Start difference. First operand has 22 states, 12 states have (on average 1.6666666666666667) internal successors, (20), 13 states have internal predecessors, (20), 7 states have call successors, (7), 1 states have call predecessors, (7), 1 states have return successors, (7), 7 states have call predecessors, (7), 7 states have call successors, (7) Second operand has 2 states, 2 states have (on average 3.0) internal successors, (6), 2 states have internal predecessors, (6), 1 states have call successors, (1), 1 states have call predecessors, (1), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2023-11-23 21:24:33,188 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:33,189 INFO L93 Difference]: Finished difference Result 43 states and 74 transitions. [2023-11-23 21:24:33,190 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 2 states. [2023-11-23 21:24:33,192 INFO L78 Accepts]: Start accepts. Automaton has has 2 states, 2 states have (on average 3.0) internal successors, (6), 2 states have internal predecessors, (6), 1 states have call successors, (1), 1 states have call predecessors, (1), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) Word has length 7 [2023-11-23 21:24:33,192 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:33,201 INFO L225 Difference]: With dead ends: 43 [2023-11-23 21:24:33,201 INFO L226 Difference]: Without dead ends: 20 [2023-11-23 21:24:33,205 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 6 GetRequests, 6 SyntacticMatches, 0 SemanticMatches, 0 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=1, Invalid=1, Unknown=0, NotChecked=0, Total=2 [2023-11-23 21:24:33,209 INFO L413 NwaCegarLoop]: 28 mSDtfsCounter, 0 mSDsluCounter, 0 mSDsCounter, 0 mSdLazyCounter, 3 mSolverCounterSat, 0 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.0s Time, 0 mProtectedPredicate, 0 mProtectedAction, 0 SdHoareTripleChecker+Valid, 28 SdHoareTripleChecker+Invalid, 3 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 0 IncrementalHoareTripleChecker+Valid, 3 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.0s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:33,211 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [0 Valid, 28 Invalid, 3 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [0 Valid, 3 Invalid, 0 Unknown, 0 Unchecked, 0.0s Time] [2023-11-23 21:24:33,231 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 20 states. [2023-11-23 21:24:33,252 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 20 to 20. [2023-11-23 21:24:33,254 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 20 states, 11 states have (on average 1.4545454545454546) internal successors, (16), 12 states have internal predecessors, (16), 7 states have call successors, (7), 1 states have call predecessors, (7), 1 states have return successors, (6), 6 states have call predecessors, (6), 6 states have call successors, (6) [2023-11-23 21:24:33,256 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 20 states to 20 states and 29 transitions. [2023-11-23 21:24:33,258 INFO L78 Accepts]: Start accepts. Automaton has 20 states and 29 transitions. Word has length 7 [2023-11-23 21:24:33,258 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:33,259 INFO L495 AbstractCegarLoop]: Abstraction has 20 states and 29 transitions. [2023-11-23 21:24:33,259 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 2 states, 2 states have (on average 3.0) internal successors, (6), 2 states have internal predecessors, (6), 1 states have call successors, (1), 1 states have call predecessors, (1), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2023-11-23 21:24:33,259 INFO L276 IsEmpty]: Start isEmpty. Operand 20 states and 29 transitions. [2023-11-23 21:24:33,260 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 8 [2023-11-23 21:24:33,261 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:33,261 INFO L195 NwaCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:33,289 INFO L540 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (2)] Forceful destruction successful, exit code 0 [2023-11-23 21:24:33,475 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0,2 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:33,476 INFO L420 AbstractCegarLoop]: === Iteration 2 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:33,476 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:33,477 INFO L85 PathProgramCache]: Analyzing trace with hash 829671692, now seen corresponding path program 1 times [2023-11-23 21:24:33,477 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:33,477 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [798146626] [2023-11-23 21:24:33,477 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:33,477 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:33,509 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:33,680 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2023-11-23 21:24:33,680 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:33,680 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [798146626] [2023-11-23 21:24:33,681 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [798146626] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-23 21:24:33,681 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-23 21:24:33,681 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [4] imperfect sequences [] total 4 [2023-11-23 21:24:33,682 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1914618181] [2023-11-23 21:24:33,682 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-23 21:24:33,686 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 5 states [2023-11-23 21:24:33,687 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:33,688 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2023-11-23 21:24:33,688 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2023-11-23 21:24:33,688 INFO L87 Difference]: Start difference. First operand 20 states and 29 transitions. Second operand has 5 states, 5 states have (on average 1.2) internal successors, (6), 3 states have internal predecessors, (6), 1 states have call successors, (1), 1 states have call predecessors, (1), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2023-11-23 21:24:33,787 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:33,788 INFO L93 Difference]: Finished difference Result 33 states and 46 transitions. [2023-11-23 21:24:33,788 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 6 states. [2023-11-23 21:24:33,789 INFO L78 Accepts]: Start accepts. Automaton has has 5 states, 5 states have (on average 1.2) internal successors, (6), 3 states have internal predecessors, (6), 1 states have call successors, (1), 1 states have call predecessors, (1), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) Word has length 7 [2023-11-23 21:24:33,789 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:33,790 INFO L225 Difference]: With dead ends: 33 [2023-11-23 21:24:33,790 INFO L226 Difference]: Without dead ends: 31 [2023-11-23 21:24:33,791 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 5 GetRequests, 1 SyntacticMatches, 0 SemanticMatches, 4 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=11, Invalid=19, Unknown=0, NotChecked=0, Total=30 [2023-11-23 21:24:33,792 INFO L413 NwaCegarLoop]: 24 mSDtfsCounter, 13 mSDsluCounter, 57 mSDsCounter, 0 mSdLazyCounter, 23 mSolverCounterSat, 1 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.0s Time, 0 mProtectedPredicate, 0 mProtectedAction, 19 SdHoareTripleChecker+Valid, 81 SdHoareTripleChecker+Invalid, 24 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 1 IncrementalHoareTripleChecker+Valid, 23 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.0s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:33,793 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [19 Valid, 81 Invalid, 24 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [1 Valid, 23 Invalid, 0 Unknown, 0 Unchecked, 0.0s Time] [2023-11-23 21:24:33,794 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 31 states. [2023-11-23 21:24:33,803 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 31 to 24. [2023-11-23 21:24:33,803 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 24 states, 14 states have (on average 1.3571428571428572) internal successors, (19), 15 states have internal predecessors, (19), 7 states have call successors, (7), 2 states have call predecessors, (7), 2 states have return successors, (6), 6 states have call predecessors, (6), 6 states have call successors, (6) [2023-11-23 21:24:33,804 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 24 states to 24 states and 32 transitions. [2023-11-23 21:24:33,805 INFO L78 Accepts]: Start accepts. Automaton has 24 states and 32 transitions. Word has length 7 [2023-11-23 21:24:33,805 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:33,805 INFO L495 AbstractCegarLoop]: Abstraction has 24 states and 32 transitions. [2023-11-23 21:24:33,805 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 5 states, 5 states have (on average 1.2) internal successors, (6), 3 states have internal predecessors, (6), 1 states have call successors, (1), 1 states have call predecessors, (1), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2023-11-23 21:24:33,806 INFO L276 IsEmpty]: Start isEmpty. Operand 24 states and 32 transitions. [2023-11-23 21:24:33,806 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 10 [2023-11-23 21:24:33,807 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:33,807 INFO L195 NwaCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:33,807 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable1 [2023-11-23 21:24:33,807 INFO L420 AbstractCegarLoop]: === Iteration 3 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:33,808 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:33,808 INFO L85 PathProgramCache]: Analyzing trace with hash -166824855, now seen corresponding path program 1 times [2023-11-23 21:24:33,809 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:33,809 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [725192332] [2023-11-23 21:24:33,809 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:33,810 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:33,823 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:33,833 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:33,833 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [725192332] [2023-11-23 21:24:33,833 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: Unsupported non-linear arithmetic [2023-11-23 21:24:33,833 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [494478239] [2023-11-23 21:24:33,834 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:33,834 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:33,834 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:33,835 INFO L229 MonitoredProcess]: Starting monitored process 3 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:24:33,844 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (3)] Waiting until timeout for monitored process [2023-11-23 21:24:33,899 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:33,900 INFO L262 TraceCheckSpWp]: Trace formula consists of 70 conjuncts, 3 conjunts are in the unsatisfiable core [2023-11-23 21:24:33,902 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:24:33,953 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2023-11-23 21:24:33,954 INFO L323 TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect [2023-11-23 21:24:33,954 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [494478239] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-23 21:24:33,954 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-23 21:24:33,955 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [3] imperfect sequences [] total 3 [2023-11-23 21:24:33,955 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1178675437] [2023-11-23 21:24:33,956 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-23 21:24:33,956 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 4 states [2023-11-23 21:24:33,957 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:33,957 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2023-11-23 21:24:33,958 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2023-11-23 21:24:33,958 INFO L87 Difference]: Start difference. First operand 24 states and 32 transitions. Second operand has 4 states, 4 states have (on average 2.0) internal successors, (8), 3 states have internal predecessors, (8), 1 states have call successors, (1), 1 states have call predecessors, (1), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2023-11-23 21:24:33,989 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:33,989 INFO L93 Difference]: Finished difference Result 39 states and 52 transitions. [2023-11-23 21:24:33,990 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 4 states. [2023-11-23 21:24:33,990 INFO L78 Accepts]: Start accepts. Automaton has has 4 states, 4 states have (on average 2.0) internal successors, (8), 3 states have internal predecessors, (8), 1 states have call successors, (1), 1 states have call predecessors, (1), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) Word has length 9 [2023-11-23 21:24:33,991 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:33,992 INFO L225 Difference]: With dead ends: 39 [2023-11-23 21:24:33,992 INFO L226 Difference]: Without dead ends: 26 [2023-11-23 21:24:33,993 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 8 GetRequests, 6 SyntacticMatches, 0 SemanticMatches, 2 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2023-11-23 21:24:33,995 INFO L413 NwaCegarLoop]: 25 mSDtfsCounter, 0 mSDsluCounter, 48 mSDsCounter, 0 mSdLazyCounter, 13 mSolverCounterSat, 0 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.0s Time, 0 mProtectedPredicate, 0 mProtectedAction, 0 SdHoareTripleChecker+Valid, 73 SdHoareTripleChecker+Invalid, 13 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 0 IncrementalHoareTripleChecker+Valid, 13 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.0s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:33,996 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [0 Valid, 73 Invalid, 13 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [0 Valid, 13 Invalid, 0 Unknown, 0 Unchecked, 0.0s Time] [2023-11-23 21:24:33,997 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 26 states. [2023-11-23 21:24:34,004 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 26 to 26. [2023-11-23 21:24:34,004 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 26 states, 16 states have (on average 1.3125) internal successors, (21), 17 states have internal predecessors, (21), 7 states have call successors, (7), 2 states have call predecessors, (7), 2 states have return successors, (6), 6 states have call predecessors, (6), 6 states have call successors, (6) [2023-11-23 21:24:34,006 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 26 states to 26 states and 34 transitions. [2023-11-23 21:24:34,006 INFO L78 Accepts]: Start accepts. Automaton has 26 states and 34 transitions. Word has length 9 [2023-11-23 21:24:34,007 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:34,007 INFO L495 AbstractCegarLoop]: Abstraction has 26 states and 34 transitions. [2023-11-23 21:24:34,007 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 4 states, 4 states have (on average 2.0) internal successors, (8), 3 states have internal predecessors, (8), 1 states have call successors, (1), 1 states have call predecessors, (1), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2023-11-23 21:24:34,008 INFO L276 IsEmpty]: Start isEmpty. Operand 26 states and 34 transitions. [2023-11-23 21:24:34,008 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 13 [2023-11-23 21:24:34,009 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:34,009 INFO L195 NwaCegarLoop]: trace histogram [2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:34,044 INFO L552 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (3)] Ended with exit code 0 [2023-11-23 21:24:34,223 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable2,3 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:34,224 INFO L420 AbstractCegarLoop]: === Iteration 4 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:34,224 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:34,224 INFO L85 PathProgramCache]: Analyzing trace with hash -439138420, now seen corresponding path program 1 times [2023-11-23 21:24:34,225 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:34,225 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [865642835] [2023-11-23 21:24:34,225 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:34,225 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:34,256 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:34,415 INFO L134 CoverageAnalysis]: Checked inductivity of 2 backedges. 2 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2023-11-23 21:24:34,416 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:34,416 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [865642835] [2023-11-23 21:24:34,416 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [865642835] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-23 21:24:34,417 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-23 21:24:34,417 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2023-11-23 21:24:34,417 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [721063490] [2023-11-23 21:24:34,417 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-23 21:24:34,418 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 5 states [2023-11-23 21:24:34,418 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:34,420 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2023-11-23 21:24:34,420 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2023-11-23 21:24:34,421 INFO L87 Difference]: Start difference. First operand 26 states and 34 transitions. Second operand has 5 states, 5 states have (on average 1.8) internal successors, (9), 4 states have internal predecessors, (9), 1 states have call successors, (2), 2 states have call predecessors, (2), 1 states have return successors, (1), 1 states have call predecessors, (1), 1 states have call successors, (1) [2023-11-23 21:24:34,474 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:34,475 INFO L93 Difference]: Finished difference Result 39 states and 51 transitions. [2023-11-23 21:24:34,475 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 6 states. [2023-11-23 21:24:34,476 INFO L78 Accepts]: Start accepts. Automaton has has 5 states, 5 states have (on average 1.8) internal successors, (9), 4 states have internal predecessors, (9), 1 states have call successors, (2), 2 states have call predecessors, (2), 1 states have return successors, (1), 1 states have call predecessors, (1), 1 states have call successors, (1) Word has length 12 [2023-11-23 21:24:34,476 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:34,477 INFO L225 Difference]: With dead ends: 39 [2023-11-23 21:24:34,477 INFO L226 Difference]: Without dead ends: 37 [2023-11-23 21:24:34,478 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 6 GetRequests, 2 SyntacticMatches, 0 SemanticMatches, 4 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=11, Invalid=19, Unknown=0, NotChecked=0, Total=30 [2023-11-23 21:24:34,480 INFO L413 NwaCegarLoop]: 25 mSDtfsCounter, 11 mSDsluCounter, 56 mSDsCounter, 0 mSdLazyCounter, 29 mSolverCounterSat, 1 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.0s Time, 0 mProtectedPredicate, 0 mProtectedAction, 16 SdHoareTripleChecker+Valid, 81 SdHoareTripleChecker+Invalid, 30 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 1 IncrementalHoareTripleChecker+Valid, 29 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.0s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:34,480 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [16 Valid, 81 Invalid, 30 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [1 Valid, 29 Invalid, 0 Unknown, 0 Unchecked, 0.0s Time] [2023-11-23 21:24:34,481 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 37 states. [2023-11-23 21:24:34,488 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 37 to 30. [2023-11-23 21:24:34,488 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 30 states, 19 states have (on average 1.263157894736842) internal successors, (24), 20 states have internal predecessors, (24), 7 states have call successors, (7), 3 states have call predecessors, (7), 3 states have return successors, (6), 6 states have call predecessors, (6), 6 states have call successors, (6) [2023-11-23 21:24:34,489 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 30 states to 30 states and 37 transitions. [2023-11-23 21:24:34,489 INFO L78 Accepts]: Start accepts. Automaton has 30 states and 37 transitions. Word has length 12 [2023-11-23 21:24:34,490 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:34,490 INFO L495 AbstractCegarLoop]: Abstraction has 30 states and 37 transitions. [2023-11-23 21:24:34,490 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 5 states, 5 states have (on average 1.8) internal successors, (9), 4 states have internal predecessors, (9), 1 states have call successors, (2), 2 states have call predecessors, (2), 1 states have return successors, (1), 1 states have call predecessors, (1), 1 states have call successors, (1) [2023-11-23 21:24:34,490 INFO L276 IsEmpty]: Start isEmpty. Operand 30 states and 37 transitions. [2023-11-23 21:24:34,491 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 18 [2023-11-23 21:24:34,491 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:34,492 INFO L195 NwaCegarLoop]: trace histogram [3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:34,492 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable3 [2023-11-23 21:24:34,492 INFO L420 AbstractCegarLoop]: === Iteration 5 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:34,493 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:34,493 INFO L85 PathProgramCache]: Analyzing trace with hash -235147060, now seen corresponding path program 1 times [2023-11-23 21:24:34,493 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:34,494 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1196218648] [2023-11-23 21:24:34,494 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:34,494 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:34,508 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:24:34,508 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [1184339265] [2023-11-23 21:24:34,508 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:34,509 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:34,509 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:34,510 INFO L229 MonitoredProcess]: Starting monitored process 4 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:24:34,556 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (4)] Waiting until timeout for monitored process [2023-11-23 21:24:34,591 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:34,595 INFO L262 TraceCheckSpWp]: Trace formula consists of 83 conjuncts, 9 conjunts are in the unsatisfiable core [2023-11-23 21:24:34,597 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:24:34,722 INFO L134 CoverageAnalysis]: Checked inductivity of 8 backedges. 4 proven. 0 refuted. 0 times theorem prover too weak. 4 trivial. 0 not checked. [2023-11-23 21:24:34,722 INFO L323 TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect [2023-11-23 21:24:34,723 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:34,723 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1196218648] [2023-11-23 21:24:34,723 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: SMT_SOLVER_CANNOT_INTERPOLATE_INPUT [2023-11-23 21:24:34,723 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1184339265] [2023-11-23 21:24:34,723 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [1184339265] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-23 21:24:34,724 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-23 21:24:34,724 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2023-11-23 21:24:34,724 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [21623146] [2023-11-23 21:24:34,724 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-23 21:24:34,726 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 5 states [2023-11-23 21:24:34,726 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:34,728 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2023-11-23 21:24:34,728 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2023-11-23 21:24:34,728 INFO L87 Difference]: Start difference. First operand 30 states and 37 transitions. Second operand has 5 states, 5 states have (on average 1.8) internal successors, (9), 4 states have internal predecessors, (9), 1 states have call successors, (3), 2 states have call predecessors, (3), 1 states have return successors, (2), 1 states have call predecessors, (2), 1 states have call successors, (2) [2023-11-23 21:24:34,831 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:34,831 INFO L93 Difference]: Finished difference Result 58 states and 78 transitions. [2023-11-23 21:24:34,832 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2023-11-23 21:24:34,832 INFO L78 Accepts]: Start accepts. Automaton has has 5 states, 5 states have (on average 1.8) internal successors, (9), 4 states have internal predecessors, (9), 1 states have call successors, (3), 2 states have call predecessors, (3), 1 states have return successors, (2), 1 states have call predecessors, (2), 1 states have call successors, (2) Word has length 17 [2023-11-23 21:24:34,832 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:34,834 INFO L225 Difference]: With dead ends: 58 [2023-11-23 21:24:34,835 INFO L226 Difference]: Without dead ends: 44 [2023-11-23 21:24:34,836 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 17 GetRequests, 13 SyntacticMatches, 0 SemanticMatches, 4 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=11, Invalid=19, Unknown=0, NotChecked=0, Total=30 [2023-11-23 21:24:34,839 INFO L413 NwaCegarLoop]: 23 mSDtfsCounter, 10 mSDsluCounter, 58 mSDsCounter, 0 mSdLazyCounter, 40 mSolverCounterSat, 3 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.0s Time, 0 mProtectedPredicate, 0 mProtectedAction, 14 SdHoareTripleChecker+Valid, 81 SdHoareTripleChecker+Invalid, 43 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 3 IncrementalHoareTripleChecker+Valid, 40 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.1s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:34,843 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [14 Valid, 81 Invalid, 43 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [3 Valid, 40 Invalid, 0 Unknown, 0 Unchecked, 0.1s Time] [2023-11-23 21:24:34,845 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 44 states. [2023-11-23 21:24:34,866 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 44 to 44. [2023-11-23 21:24:34,867 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 44 states, 26 states have (on average 1.2692307692307692) internal successors, (33), 28 states have internal predecessors, (33), 13 states have call successors, (13), 4 states have call predecessors, (13), 4 states have return successors, (11), 11 states have call predecessors, (11), 11 states have call successors, (11) [2023-11-23 21:24:34,872 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 44 states to 44 states and 57 transitions. [2023-11-23 21:24:34,872 INFO L78 Accepts]: Start accepts. Automaton has 44 states and 57 transitions. Word has length 17 [2023-11-23 21:24:34,874 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:34,874 INFO L495 AbstractCegarLoop]: Abstraction has 44 states and 57 transitions. [2023-11-23 21:24:34,874 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 5 states, 5 states have (on average 1.8) internal successors, (9), 4 states have internal predecessors, (9), 1 states have call successors, (3), 2 states have call predecessors, (3), 1 states have return successors, (2), 1 states have call predecessors, (2), 1 states have call successors, (2) [2023-11-23 21:24:34,880 INFO L276 IsEmpty]: Start isEmpty. Operand 44 states and 57 transitions. [2023-11-23 21:24:34,881 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 26 [2023-11-23 21:24:34,882 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:34,882 INFO L195 NwaCegarLoop]: trace histogram [4, 3, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:34,903 INFO L540 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (4)] Forceful destruction successful, exit code 0 [2023-11-23 21:24:35,099 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable4,4 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:35,100 INFO L420 AbstractCegarLoop]: === Iteration 6 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:35,100 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:35,100 INFO L85 PathProgramCache]: Analyzing trace with hash 2012527405, now seen corresponding path program 1 times [2023-11-23 21:24:35,100 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:35,100 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1464984329] [2023-11-23 21:24:35,100 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:35,101 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:35,109 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:24:35,110 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [153519017] [2023-11-23 21:24:35,110 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:35,110 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:35,110 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:35,111 INFO L229 MonitoredProcess]: Starting monitored process 5 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:24:35,122 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (5)] Waiting until timeout for monitored process [2023-11-23 21:24:35,178 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:35,180 INFO L262 TraceCheckSpWp]: Trace formula consists of 98 conjuncts, 15 conjunts are in the unsatisfiable core [2023-11-23 21:24:35,189 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:24:35,342 INFO L134 CoverageAnalysis]: Checked inductivity of 18 backedges. 5 proven. 7 refuted. 0 times theorem prover too weak. 6 trivial. 0 not checked. [2023-11-23 21:24:35,343 INFO L327 TraceCheckSpWp]: Computing backward predicates... [2023-11-23 21:24:35,570 INFO L134 CoverageAnalysis]: Checked inductivity of 18 backedges. 5 proven. 7 refuted. 0 times theorem prover too weak. 6 trivial. 0 not checked. [2023-11-23 21:24:35,570 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:35,570 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1464984329] [2023-11-23 21:24:35,570 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: SMT_SOLVER_CANNOT_INTERPOLATE_INPUT [2023-11-23 21:24:35,571 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [153519017] [2023-11-23 21:24:35,571 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [153519017] provided 0 perfect and 2 imperfect interpolant sequences [2023-11-23 21:24:35,571 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSifa [72912895] [2023-11-23 21:24:35,593 INFO L159 IcfgInterpreter]: Started Sifa with 16 locations of interest [2023-11-23 21:24:35,594 INFO L166 IcfgInterpreter]: Building call graph [2023-11-23 21:24:35,597 INFO L171 IcfgInterpreter]: Initial procedures are [ULTIMATE.start] [2023-11-23 21:24:35,603 INFO L176 IcfgInterpreter]: Starting interpretation [2023-11-23 21:24:35,604 INFO L197 IcfgInterpreter]: Interpreting procedure ULTIMATE.start with input of size 1 for LOIs [2023-11-23 21:24:36,875 INFO L197 IcfgInterpreter]: Interpreting procedure __VERIFIER_assert with input of size 10 for LOIs [2023-11-23 21:24:36,884 INFO L180 IcfgInterpreter]: Interpretation finished [2023-11-23 21:24:38,102 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSifa [72912895] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-23 21:24:38,103 INFO L185 FreeRefinementEngine]: Found 1 perfect and 2 imperfect interpolant sequences. [2023-11-23 21:24:38,103 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [9] imperfect sequences [7, 7] total 18 [2023-11-23 21:24:38,104 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1179768375] [2023-11-23 21:24:38,104 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-23 21:24:38,105 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 10 states [2023-11-23 21:24:38,105 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:38,107 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 10 interpolants. [2023-11-23 21:24:38,108 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=64, Invalid=242, Unknown=0, NotChecked=0, Total=306 [2023-11-23 21:24:38,108 INFO L87 Difference]: Start difference. First operand 44 states and 57 transitions. Second operand has 10 states, 9 states have (on average 1.2222222222222223) internal successors, (11), 8 states have internal predecessors, (11), 2 states have call successors, (4), 1 states have call predecessors, (4), 1 states have return successors, (3), 1 states have call predecessors, (3), 1 states have call successors, (3) [2023-11-23 21:24:38,436 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:38,436 INFO L93 Difference]: Finished difference Result 63 states and 73 transitions. [2023-11-23 21:24:38,437 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 10 states. [2023-11-23 21:24:38,437 INFO L78 Accepts]: Start accepts. Automaton has has 10 states, 9 states have (on average 1.2222222222222223) internal successors, (11), 8 states have internal predecessors, (11), 2 states have call successors, (4), 1 states have call predecessors, (4), 1 states have return successors, (3), 1 states have call predecessors, (3), 1 states have call successors, (3) Word has length 25 [2023-11-23 21:24:38,439 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:38,441 INFO L225 Difference]: With dead ends: 63 [2023-11-23 21:24:38,441 INFO L226 Difference]: Without dead ends: 46 [2023-11-23 21:24:38,442 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 73 GetRequests, 53 SyntacticMatches, 4 SemanticMatches, 16 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 87 ImplicationChecksByTransitivity, 1.3s TimeCoverageRelationStatistics Valid=64, Invalid=242, Unknown=0, NotChecked=0, Total=306 [2023-11-23 21:24:38,443 INFO L413 NwaCegarLoop]: 16 mSDtfsCounter, 1 mSDsluCounter, 66 mSDsCounter, 0 mSdLazyCounter, 174 mSolverCounterSat, 3 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.3s Time, 0 mProtectedPredicate, 0 mProtectedAction, 3 SdHoareTripleChecker+Valid, 82 SdHoareTripleChecker+Invalid, 177 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 3 IncrementalHoareTripleChecker+Valid, 174 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.3s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:38,444 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [3 Valid, 82 Invalid, 177 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [3 Valid, 174 Invalid, 0 Unknown, 0 Unchecked, 0.3s Time] [2023-11-23 21:24:38,445 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 46 states. [2023-11-23 21:24:38,467 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 46 to 46. [2023-11-23 21:24:38,468 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 46 states, 29 states have (on average 1.1724137931034482) internal successors, (34), 30 states have internal predecessors, (34), 10 states have call successors, (10), 6 states have call predecessors, (10), 6 states have return successors, (9), 9 states have call predecessors, (9), 9 states have call successors, (9) [2023-11-23 21:24:38,473 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 46 states to 46 states and 53 transitions. [2023-11-23 21:24:38,474 INFO L78 Accepts]: Start accepts. Automaton has 46 states and 53 transitions. Word has length 25 [2023-11-23 21:24:38,474 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:38,474 INFO L495 AbstractCegarLoop]: Abstraction has 46 states and 53 transitions. [2023-11-23 21:24:38,475 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 10 states, 9 states have (on average 1.2222222222222223) internal successors, (11), 8 states have internal predecessors, (11), 2 states have call successors, (4), 1 states have call predecessors, (4), 1 states have return successors, (3), 1 states have call predecessors, (3), 1 states have call successors, (3) [2023-11-23 21:24:38,475 INFO L276 IsEmpty]: Start isEmpty. Operand 46 states and 53 transitions. [2023-11-23 21:24:38,476 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 28 [2023-11-23 21:24:38,476 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:38,477 INFO L195 NwaCegarLoop]: trace histogram [4, 3, 3, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:38,503 INFO L540 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (5)] Forceful destruction successful, exit code 0 [2023-11-23 21:24:38,697 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable5,5 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:38,697 INFO L420 AbstractCegarLoop]: === Iteration 7 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:38,698 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:38,698 INFO L85 PathProgramCache]: Analyzing trace with hash 2127759890, now seen corresponding path program 1 times [2023-11-23 21:24:38,698 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:38,698 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [2087811473] [2023-11-23 21:24:38,698 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:38,698 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:38,709 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:24:38,710 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [558918219] [2023-11-23 21:24:38,710 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:38,710 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:38,710 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:38,711 INFO L229 MonitoredProcess]: Starting monitored process 6 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:24:38,743 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (6)] Waiting until timeout for monitored process [2023-11-23 21:24:38,774 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:38,775 INFO L262 TraceCheckSpWp]: Trace formula consists of 107 conjuncts, 5 conjunts are in the unsatisfiable core [2023-11-23 21:24:38,777 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:24:38,822 INFO L134 CoverageAnalysis]: Checked inductivity of 20 backedges. 6 proven. 2 refuted. 0 times theorem prover too weak. 12 trivial. 0 not checked. [2023-11-23 21:24:38,822 INFO L327 TraceCheckSpWp]: Computing backward predicates... [2023-11-23 21:24:38,868 INFO L134 CoverageAnalysis]: Checked inductivity of 20 backedges. 6 proven. 2 refuted. 0 times theorem prover too weak. 12 trivial. 0 not checked. [2023-11-23 21:24:38,868 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:38,868 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [2087811473] [2023-11-23 21:24:38,869 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: SMT_SOLVER_CANNOT_INTERPOLATE_INPUT [2023-11-23 21:24:38,869 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [558918219] [2023-11-23 21:24:38,869 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [558918219] provided 0 perfect and 2 imperfect interpolant sequences [2023-11-23 21:24:38,869 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSifa [716040572] [2023-11-23 21:24:38,874 INFO L159 IcfgInterpreter]: Started Sifa with 16 locations of interest [2023-11-23 21:24:38,874 INFO L166 IcfgInterpreter]: Building call graph [2023-11-23 21:24:38,875 INFO L171 IcfgInterpreter]: Initial procedures are [ULTIMATE.start] [2023-11-23 21:24:38,875 INFO L176 IcfgInterpreter]: Starting interpretation [2023-11-23 21:24:38,875 INFO L197 IcfgInterpreter]: Interpreting procedure ULTIMATE.start with input of size 1 for LOIs [2023-11-23 21:24:41,202 INFO L197 IcfgInterpreter]: Interpreting procedure __VERIFIER_assert with input of size 10 for LOIs [2023-11-23 21:24:41,215 INFO L180 IcfgInterpreter]: Interpretation finished [2023-11-23 21:24:42,512 INFO L133 SifaRunner]: Sifa could not show that error location is unreachable, found '1145#(and (<= 1 |#StackHeapBarrier|) (<= 1 ~counter~0) (= |__VERIFIER_assert_#in~cond| 0) (= __VERIFIER_assert_~cond 0))' at error location [2023-11-23 21:24:42,512 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: ALGORITHM_FAILED [2023-11-23 21:24:42,513 INFO L185 FreeRefinementEngine]: Found 0 perfect and 2 imperfect interpolant sequences. [2023-11-23 21:24:42,513 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [4, 5] total 8 [2023-11-23 21:24:42,513 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1811007844] [2023-11-23 21:24:42,513 INFO L85 oduleStraightlineAll]: Using 2 imperfect interpolants to construct interpolant automaton [2023-11-23 21:24:42,514 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 8 states [2023-11-23 21:24:42,514 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:42,515 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 8 interpolants. [2023-11-23 21:24:42,515 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=68, Invalid=274, Unknown=0, NotChecked=0, Total=342 [2023-11-23 21:24:42,515 INFO L87 Difference]: Start difference. First operand 46 states and 53 transitions. Second operand has 8 states, 8 states have (on average 2.875) internal successors, (23), 8 states have internal predecessors, (23), 3 states have call successors, (7), 3 states have call predecessors, (7), 2 states have return successors, (6), 2 states have call predecessors, (6), 2 states have call successors, (6) [2023-11-23 21:24:42,708 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:42,709 INFO L93 Difference]: Finished difference Result 109 states and 130 transitions. [2023-11-23 21:24:42,709 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 10 states. [2023-11-23 21:24:42,710 INFO L78 Accepts]: Start accepts. Automaton has has 8 states, 8 states have (on average 2.875) internal successors, (23), 8 states have internal predecessors, (23), 3 states have call successors, (7), 3 states have call predecessors, (7), 2 states have return successors, (6), 2 states have call predecessors, (6), 2 states have call successors, (6) Word has length 27 [2023-11-23 21:24:42,710 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:42,711 INFO L225 Difference]: With dead ends: 109 [2023-11-23 21:24:42,712 INFO L226 Difference]: Without dead ends: 96 [2023-11-23 21:24:42,713 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 82 GetRequests, 62 SyntacticMatches, 0 SemanticMatches, 20 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 107 ImplicationChecksByTransitivity, 1.4s TimeCoverageRelationStatistics Valid=88, Invalid=374, Unknown=0, NotChecked=0, Total=462 [2023-11-23 21:24:42,714 INFO L413 NwaCegarLoop]: 24 mSDtfsCounter, 34 mSDsluCounter, 72 mSDsCounter, 0 mSdLazyCounter, 49 mSolverCounterSat, 2 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.1s Time, 0 mProtectedPredicate, 0 mProtectedAction, 34 SdHoareTripleChecker+Valid, 96 SdHoareTripleChecker+Invalid, 51 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 2 IncrementalHoareTripleChecker+Valid, 49 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.1s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:42,714 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [34 Valid, 96 Invalid, 51 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [2 Valid, 49 Invalid, 0 Unknown, 0 Unchecked, 0.1s Time] [2023-11-23 21:24:42,715 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 96 states. [2023-11-23 21:24:42,730 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 96 to 91. [2023-11-23 21:24:42,730 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 91 states, 58 states have (on average 1.1896551724137931) internal successors, (69), 60 states have internal predecessors, (69), 20 states have call successors, (20), 12 states have call predecessors, (20), 12 states have return successors, (18), 18 states have call predecessors, (18), 18 states have call successors, (18) [2023-11-23 21:24:42,732 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 91 states to 91 states and 107 transitions. [2023-11-23 21:24:42,732 INFO L78 Accepts]: Start accepts. Automaton has 91 states and 107 transitions. Word has length 27 [2023-11-23 21:24:42,732 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:42,733 INFO L495 AbstractCegarLoop]: Abstraction has 91 states and 107 transitions. [2023-11-23 21:24:42,733 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 8 states, 8 states have (on average 2.875) internal successors, (23), 8 states have internal predecessors, (23), 3 states have call successors, (7), 3 states have call predecessors, (7), 2 states have return successors, (6), 2 states have call predecessors, (6), 2 states have call successors, (6) [2023-11-23 21:24:42,733 INFO L276 IsEmpty]: Start isEmpty. Operand 91 states and 107 transitions. [2023-11-23 21:24:42,734 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 36 [2023-11-23 21:24:42,735 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:42,735 INFO L195 NwaCegarLoop]: trace histogram [6, 5, 5, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1] [2023-11-23 21:24:42,763 INFO L540 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (6)] Forceful destruction successful, exit code 0 [2023-11-23 21:24:42,950 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable6,6 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:42,950 INFO L420 AbstractCegarLoop]: === Iteration 8 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:42,951 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:42,951 INFO L85 PathProgramCache]: Analyzing trace with hash 747162997, now seen corresponding path program 1 times [2023-11-23 21:24:42,951 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:42,951 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1454205361] [2023-11-23 21:24:42,951 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:42,952 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:42,970 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:24:42,979 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [1023980096] [2023-11-23 21:24:42,979 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:42,979 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:42,980 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:42,988 INFO L229 MonitoredProcess]: Starting monitored process 7 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:24:43,011 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (7)] Waiting until timeout for monitored process [2023-11-23 21:24:43,063 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:43,064 INFO L262 TraceCheckSpWp]: Trace formula consists of 120 conjuncts, 13 conjunts are in the unsatisfiable core [2023-11-23 21:24:43,066 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:24:43,183 INFO L134 CoverageAnalysis]: Checked inductivity of 55 backedges. 10 proven. 5 refuted. 0 times theorem prover too weak. 40 trivial. 0 not checked. [2023-11-23 21:24:43,183 INFO L327 TraceCheckSpWp]: Computing backward predicates... [2023-11-23 21:24:43,270 INFO L134 CoverageAnalysis]: Checked inductivity of 55 backedges. 10 proven. 0 refuted. 0 times theorem prover too weak. 45 trivial. 0 not checked. [2023-11-23 21:24:43,270 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:43,270 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1454205361] [2023-11-23 21:24:43,270 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: SMT_SOLVER_CANNOT_INTERPOLATE_INPUT [2023-11-23 21:24:43,270 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1023980096] [2023-11-23 21:24:43,271 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [1023980096] provided 1 perfect and 1 imperfect interpolant sequences [2023-11-23 21:24:43,271 INFO L185 FreeRefinementEngine]: Found 1 perfect and 1 imperfect interpolant sequences. [2023-11-23 21:24:43,271 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [6] total 7 [2023-11-23 21:24:43,271 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1241627552] [2023-11-23 21:24:43,271 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-23 21:24:43,272 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 5 states [2023-11-23 21:24:43,272 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:43,273 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2023-11-23 21:24:43,273 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=13, Invalid=29, Unknown=0, NotChecked=0, Total=42 [2023-11-23 21:24:43,273 INFO L87 Difference]: Start difference. First operand 91 states and 107 transitions. Second operand has 5 states, 5 states have (on average 2.0) internal successors, (10), 4 states have internal predecessors, (10), 1 states have call successors, (4), 2 states have call predecessors, (4), 1 states have return successors, (3), 1 states have call predecessors, (3), 1 states have call successors, (3) [2023-11-23 21:24:44,151 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:44,151 INFO L93 Difference]: Finished difference Result 108 states and 128 transitions. [2023-11-23 21:24:44,152 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2023-11-23 21:24:44,152 INFO L78 Accepts]: Start accepts. Automaton has has 5 states, 5 states have (on average 2.0) internal successors, (10), 4 states have internal predecessors, (10), 1 states have call successors, (4), 2 states have call predecessors, (4), 1 states have return successors, (3), 1 states have call predecessors, (3), 1 states have call successors, (3) Word has length 35 [2023-11-23 21:24:44,153 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:44,154 INFO L225 Difference]: With dead ends: 108 [2023-11-23 21:24:44,154 INFO L226 Difference]: Without dead ends: 106 [2023-11-23 21:24:44,155 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 69 GetRequests, 61 SyntacticMatches, 2 SemanticMatches, 6 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.1s TimeCoverageRelationStatistics Valid=17, Invalid=39, Unknown=0, NotChecked=0, Total=56 [2023-11-23 21:24:44,156 INFO L413 NwaCegarLoop]: 23 mSDtfsCounter, 11 mSDsluCounter, 52 mSDsCounter, 0 mSdLazyCounter, 37 mSolverCounterSat, 1 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.8s Time, 0 mProtectedPredicate, 0 mProtectedAction, 14 SdHoareTripleChecker+Valid, 75 SdHoareTripleChecker+Invalid, 38 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 1 IncrementalHoareTripleChecker+Valid, 37 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.8s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:44,157 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [14 Valid, 75 Invalid, 38 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [1 Valid, 37 Invalid, 0 Unknown, 0 Unchecked, 0.8s Time] [2023-11-23 21:24:44,158 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 106 states. [2023-11-23 21:24:44,176 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 106 to 103. [2023-11-23 21:24:44,177 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 103 states, 66 states have (on average 1.1666666666666667) internal successors, (77), 69 states have internal predecessors, (77), 22 states have call successors, (22), 14 states have call predecessors, (22), 14 states have return successors, (20), 19 states have call predecessors, (20), 20 states have call successors, (20) [2023-11-23 21:24:44,178 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 103 states to 103 states and 119 transitions. [2023-11-23 21:24:44,179 INFO L78 Accepts]: Start accepts. Automaton has 103 states and 119 transitions. Word has length 35 [2023-11-23 21:24:44,179 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:44,180 INFO L495 AbstractCegarLoop]: Abstraction has 103 states and 119 transitions. [2023-11-23 21:24:44,180 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 5 states, 5 states have (on average 2.0) internal successors, (10), 4 states have internal predecessors, (10), 1 states have call successors, (4), 2 states have call predecessors, (4), 1 states have return successors, (3), 1 states have call predecessors, (3), 1 states have call successors, (3) [2023-11-23 21:24:44,180 INFO L276 IsEmpty]: Start isEmpty. Operand 103 states and 119 transitions. [2023-11-23 21:24:44,182 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 44 [2023-11-23 21:24:44,182 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:44,182 INFO L195 NwaCegarLoop]: trace histogram [7, 6, 6, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:44,207 INFO L540 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (7)] Forceful destruction successful, exit code 0 [2023-11-23 21:24:44,407 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable7,7 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:44,407 INFO L420 AbstractCegarLoop]: === Iteration 9 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:44,408 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:44,408 INFO L85 PathProgramCache]: Analyzing trace with hash 387112662, now seen corresponding path program 1 times [2023-11-23 21:24:44,408 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:44,408 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1202536060] [2023-11-23 21:24:44,409 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:44,409 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:44,432 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:24:44,432 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [770700965] [2023-11-23 21:24:44,433 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:44,433 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:44,433 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:44,435 INFO L229 MonitoredProcess]: Starting monitored process 8 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:24:44,437 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (8)] Waiting until timeout for monitored process [2023-11-23 21:24:44,497 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:44,498 INFO L262 TraceCheckSpWp]: Trace formula consists of 135 conjuncts, 7 conjunts are in the unsatisfiable core [2023-11-23 21:24:44,500 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:24:44,587 INFO L134 CoverageAnalysis]: Checked inductivity of 78 backedges. 12 proven. 0 refuted. 0 times theorem prover too weak. 66 trivial. 0 not checked. [2023-11-23 21:24:44,587 INFO L323 TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect [2023-11-23 21:24:44,588 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:44,588 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1202536060] [2023-11-23 21:24:44,588 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: SMT_SOLVER_CANNOT_INTERPOLATE_INPUT [2023-11-23 21:24:44,588 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [770700965] [2023-11-23 21:24:44,588 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [770700965] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-23 21:24:44,588 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-23 21:24:44,588 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2023-11-23 21:24:44,589 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1414441016] [2023-11-23 21:24:44,589 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-23 21:24:44,589 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 5 states [2023-11-23 21:24:44,589 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:44,590 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2023-11-23 21:24:44,590 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2023-11-23 21:24:44,590 INFO L87 Difference]: Start difference. First operand 103 states and 119 transitions. Second operand has 5 states, 5 states have (on average 2.6) internal successors, (13), 4 states have internal predecessors, (13), 1 states have call successors, (4), 2 states have call predecessors, (4), 1 states have return successors, (3), 1 states have call predecessors, (3), 1 states have call successors, (3) [2023-11-23 21:24:44,665 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:44,665 INFO L93 Difference]: Finished difference Result 116 states and 133 transitions. [2023-11-23 21:24:44,665 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2023-11-23 21:24:44,666 INFO L78 Accepts]: Start accepts. Automaton has has 5 states, 5 states have (on average 2.6) internal successors, (13), 4 states have internal predecessors, (13), 1 states have call successors, (4), 2 states have call predecessors, (4), 1 states have return successors, (3), 1 states have call predecessors, (3), 1 states have call successors, (3) Word has length 43 [2023-11-23 21:24:44,666 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:44,668 INFO L225 Difference]: With dead ends: 116 [2023-11-23 21:24:44,668 INFO L226 Difference]: Without dead ends: 112 [2023-11-23 21:24:44,669 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 43 GetRequests, 39 SyntacticMatches, 0 SemanticMatches, 4 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=11, Invalid=19, Unknown=0, NotChecked=0, Total=30 [2023-11-23 21:24:44,670 INFO L413 NwaCegarLoop]: 19 mSDtfsCounter, 8 mSDsluCounter, 48 mSDsCounter, 0 mSdLazyCounter, 38 mSolverCounterSat, 3 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.0s Time, 0 mProtectedPredicate, 0 mProtectedAction, 11 SdHoareTripleChecker+Valid, 67 SdHoareTripleChecker+Invalid, 41 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 3 IncrementalHoareTripleChecker+Valid, 38 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.1s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:44,670 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [11 Valid, 67 Invalid, 41 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [3 Valid, 38 Invalid, 0 Unknown, 0 Unchecked, 0.1s Time] [2023-11-23 21:24:44,671 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 112 states. [2023-11-23 21:24:44,691 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 112 to 111. [2023-11-23 21:24:44,691 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 111 states, 72 states have (on average 1.1527777777777777) internal successors, (83), 74 states have internal predecessors, (83), 23 states have call successors, (23), 16 states have call predecessors, (23), 15 states have return successors, (21), 20 states have call predecessors, (21), 21 states have call successors, (21) [2023-11-23 21:24:44,693 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 111 states to 111 states and 127 transitions. [2023-11-23 21:24:44,693 INFO L78 Accepts]: Start accepts. Automaton has 111 states and 127 transitions. Word has length 43 [2023-11-23 21:24:44,693 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:44,694 INFO L495 AbstractCegarLoop]: Abstraction has 111 states and 127 transitions. [2023-11-23 21:24:44,694 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 5 states, 5 states have (on average 2.6) internal successors, (13), 4 states have internal predecessors, (13), 1 states have call successors, (4), 2 states have call predecessors, (4), 1 states have return successors, (3), 1 states have call predecessors, (3), 1 states have call successors, (3) [2023-11-23 21:24:44,694 INFO L276 IsEmpty]: Start isEmpty. Operand 111 states and 127 transitions. [2023-11-23 21:24:44,696 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 49 [2023-11-23 21:24:44,696 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:44,696 INFO L195 NwaCegarLoop]: trace histogram [8, 7, 7, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:44,727 INFO L540 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (8)] Forceful destruction successful, exit code 0 [2023-11-23 21:24:44,917 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable8,8 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:44,918 INFO L420 AbstractCegarLoop]: === Iteration 10 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:44,918 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:44,918 INFO L85 PathProgramCache]: Analyzing trace with hash 1125945480, now seen corresponding path program 1 times [2023-11-23 21:24:44,918 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:44,919 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1652385555] [2023-11-23 21:24:44,919 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:44,919 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:44,929 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:24:44,930 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [1063399261] [2023-11-23 21:24:44,930 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:44,930 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:44,930 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:44,931 INFO L229 MonitoredProcess]: Starting monitored process 9 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:24:44,958 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (9)] Waiting until timeout for monitored process [2023-11-23 21:24:44,994 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:44,995 INFO L262 TraceCheckSpWp]: Trace formula consists of 144 conjuncts, 7 conjunts are in the unsatisfiable core [2023-11-23 21:24:44,998 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:24:45,067 INFO L134 CoverageAnalysis]: Checked inductivity of 104 backedges. 36 proven. 42 refuted. 0 times theorem prover too weak. 26 trivial. 0 not checked. [2023-11-23 21:24:45,067 INFO L327 TraceCheckSpWp]: Computing backward predicates... [2023-11-23 21:24:45,153 INFO L134 CoverageAnalysis]: Checked inductivity of 104 backedges. 14 proven. 6 refuted. 0 times theorem prover too weak. 84 trivial. 0 not checked. [2023-11-23 21:24:45,154 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:45,154 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1652385555] [2023-11-23 21:24:45,154 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: SMT_SOLVER_CANNOT_INTERPOLATE_INPUT [2023-11-23 21:24:45,154 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1063399261] [2023-11-23 21:24:45,154 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [1063399261] provided 0 perfect and 2 imperfect interpolant sequences [2023-11-23 21:24:45,155 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSifa [2048289370] [2023-11-23 21:24:45,158 INFO L159 IcfgInterpreter]: Started Sifa with 17 locations of interest [2023-11-23 21:24:45,159 INFO L166 IcfgInterpreter]: Building call graph [2023-11-23 21:24:45,160 INFO L171 IcfgInterpreter]: Initial procedures are [ULTIMATE.start] [2023-11-23 21:24:45,161 INFO L176 IcfgInterpreter]: Starting interpretation [2023-11-23 21:24:45,161 INFO L197 IcfgInterpreter]: Interpreting procedure ULTIMATE.start with input of size 1 for LOIs [2023-11-23 21:24:47,088 INFO L197 IcfgInterpreter]: Interpreting procedure __VERIFIER_assert with input of size 10 for LOIs [2023-11-23 21:24:47,098 INFO L180 IcfgInterpreter]: Interpretation finished [2023-11-23 21:24:48,287 INFO L133 SifaRunner]: Sifa could not show that error location is unreachable, found '2708#(and (<= 1 |#StackHeapBarrier|) (<= 1 ~counter~0) (= |__VERIFIER_assert_#in~cond| 0) (= __VERIFIER_assert_~cond 0))' at error location [2023-11-23 21:24:48,288 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: ALGORITHM_FAILED [2023-11-23 21:24:48,288 INFO L185 FreeRefinementEngine]: Found 0 perfect and 2 imperfect interpolant sequences. [2023-11-23 21:24:48,288 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [5, 6] total 10 [2023-11-23 21:24:48,288 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1899360413] [2023-11-23 21:24:48,288 INFO L85 oduleStraightlineAll]: Using 2 imperfect interpolants to construct interpolant automaton [2023-11-23 21:24:48,289 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 10 states [2023-11-23 21:24:48,289 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:48,290 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 10 interpolants. [2023-11-23 21:24:48,290 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=86, Invalid=376, Unknown=0, NotChecked=0, Total=462 [2023-11-23 21:24:48,290 INFO L87 Difference]: Start difference. First operand 111 states and 127 transitions. Second operand has 10 states, 10 states have (on average 3.2) internal successors, (32), 10 states have internal predecessors, (32), 5 states have call successors, (15), 4 states have call predecessors, (15), 4 states have return successors, (14), 5 states have call predecessors, (14), 5 states have call successors, (14) [2023-11-23 21:24:48,514 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:48,515 INFO L93 Difference]: Finished difference Result 219 states and 255 transitions. [2023-11-23 21:24:48,518 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 12 states. [2023-11-23 21:24:48,518 INFO L78 Accepts]: Start accepts. Automaton has has 10 states, 10 states have (on average 3.2) internal successors, (32), 10 states have internal predecessors, (32), 5 states have call successors, (15), 4 states have call predecessors, (15), 4 states have return successors, (14), 5 states have call predecessors, (14), 5 states have call successors, (14) Word has length 48 [2023-11-23 21:24:48,519 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:48,522 INFO L225 Difference]: With dead ends: 219 [2023-11-23 21:24:48,522 INFO L226 Difference]: Without dead ends: 198 [2023-11-23 21:24:48,523 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 145 GetRequests, 121 SyntacticMatches, 1 SemanticMatches, 23 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 177 ImplicationChecksByTransitivity, 1.3s TimeCoverageRelationStatistics Valid=105, Invalid=495, Unknown=0, NotChecked=0, Total=600 [2023-11-23 21:24:48,524 INFO L413 NwaCegarLoop]: 26 mSDtfsCounter, 71 mSDsluCounter, 101 mSDsCounter, 0 mSdLazyCounter, 91 mSolverCounterSat, 15 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.1s Time, 0 mProtectedPredicate, 0 mProtectedAction, 71 SdHoareTripleChecker+Valid, 127 SdHoareTripleChecker+Invalid, 106 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 15 IncrementalHoareTripleChecker+Valid, 91 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.1s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:48,524 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [71 Valid, 127 Invalid, 106 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [15 Valid, 91 Invalid, 0 Unknown, 0 Unchecked, 0.1s Time] [2023-11-23 21:24:48,525 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 198 states. [2023-11-23 21:24:48,549 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 198 to 191. [2023-11-23 21:24:48,550 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 191 states, 122 states have (on average 1.1557377049180328) internal successors, (141), 128 states have internal predecessors, (141), 43 states have call successors, (43), 26 states have call predecessors, (43), 25 states have return successors, (39), 36 states have call predecessors, (39), 39 states have call successors, (39) [2023-11-23 21:24:48,551 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 191 states to 191 states and 223 transitions. [2023-11-23 21:24:48,552 INFO L78 Accepts]: Start accepts. Automaton has 191 states and 223 transitions. Word has length 48 [2023-11-23 21:24:48,552 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:48,552 INFO L495 AbstractCegarLoop]: Abstraction has 191 states and 223 transitions. [2023-11-23 21:24:48,553 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 10 states, 10 states have (on average 3.2) internal successors, (32), 10 states have internal predecessors, (32), 5 states have call successors, (15), 4 states have call predecessors, (15), 4 states have return successors, (14), 5 states have call predecessors, (14), 5 states have call successors, (14) [2023-11-23 21:24:48,553 INFO L276 IsEmpty]: Start isEmpty. Operand 191 states and 223 transitions. [2023-11-23 21:24:48,555 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 57 [2023-11-23 21:24:48,555 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:48,555 INFO L195 NwaCegarLoop]: trace histogram [9, 8, 8, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:48,577 INFO L540 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (9)] Forceful destruction successful, exit code 0 [2023-11-23 21:24:48,767 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable9,9 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:48,767 INFO L420 AbstractCegarLoop]: === Iteration 11 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:48,768 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:48,768 INFO L85 PathProgramCache]: Analyzing trace with hash -1127123487, now seen corresponding path program 1 times [2023-11-23 21:24:48,768 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:48,768 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [673138140] [2023-11-23 21:24:48,768 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:48,768 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:48,776 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:24:48,776 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [1521309174] [2023-11-23 21:24:48,776 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:48,776 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:48,776 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:48,777 INFO L229 MonitoredProcess]: Starting monitored process 10 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:24:48,797 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (10)] Waiting until timeout for monitored process [2023-11-23 21:24:48,838 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:24:48,840 INFO L262 TraceCheckSpWp]: Trace formula consists of 164 conjuncts, 23 conjunts are in the unsatisfiable core [2023-11-23 21:24:48,843 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:24:49,146 INFO L134 CoverageAnalysis]: Checked inductivity of 137 backedges. 16 proven. 9 refuted. 0 times theorem prover too weak. 112 trivial. 0 not checked. [2023-11-23 21:24:49,147 INFO L327 TraceCheckSpWp]: Computing backward predicates... [2023-11-23 21:24:52,146 INFO L134 CoverageAnalysis]: Checked inductivity of 137 backedges. 16 proven. 9 refuted. 0 times theorem prover too weak. 112 trivial. 0 not checked. [2023-11-23 21:24:52,146 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:52,147 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [673138140] [2023-11-23 21:24:52,147 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: SMT_SOLVER_CANNOT_INTERPOLATE_INPUT [2023-11-23 21:24:52,147 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1521309174] [2023-11-23 21:24:52,147 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [1521309174] provided 0 perfect and 2 imperfect interpolant sequences [2023-11-23 21:24:52,147 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSifa [135733480] [2023-11-23 21:24:52,150 INFO L159 IcfgInterpreter]: Started Sifa with 18 locations of interest [2023-11-23 21:24:52,150 INFO L166 IcfgInterpreter]: Building call graph [2023-11-23 21:24:52,150 INFO L171 IcfgInterpreter]: Initial procedures are [ULTIMATE.start] [2023-11-23 21:24:52,151 INFO L176 IcfgInterpreter]: Starting interpretation [2023-11-23 21:24:52,151 INFO L197 IcfgInterpreter]: Interpreting procedure ULTIMATE.start with input of size 1 for LOIs [2023-11-23 21:24:54,506 INFO L197 IcfgInterpreter]: Interpreting procedure __VERIFIER_assert with input of size 1 for LOIs [2023-11-23 21:24:54,510 INFO L180 IcfgInterpreter]: Interpretation finished [2023-11-23 21:24:55,695 INFO L133 SifaRunner]: Sifa could not show that error location is unreachable, found '3654#(and (= |__VERIFIER_assert_#in~cond| 0) (= __VERIFIER_assert_~cond 0))' at error location [2023-11-23 21:24:55,695 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: ALGORITHM_FAILED [2023-11-23 21:24:55,695 INFO L185 FreeRefinementEngine]: Found 0 perfect and 2 imperfect interpolant sequences. [2023-11-23 21:24:55,695 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [7, 7] total 10 [2023-11-23 21:24:55,696 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1616618995] [2023-11-23 21:24:55,696 INFO L85 oduleStraightlineAll]: Using 2 imperfect interpolants to construct interpolant automaton [2023-11-23 21:24:55,696 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 10 states [2023-11-23 21:24:55,697 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:24:55,697 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 10 interpolants. [2023-11-23 21:24:55,698 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=74, Invalid=388, Unknown=0, NotChecked=0, Total=462 [2023-11-23 21:24:55,698 INFO L87 Difference]: Start difference. First operand 191 states and 223 transitions. Second operand has 10 states, 10 states have (on average 3.0) internal successors, (30), 9 states have internal predecessors, (30), 6 states have call successors, (18), 2 states have call predecessors, (18), 1 states have return successors, (16), 4 states have call predecessors, (16), 4 states have call successors, (16) [2023-11-23 21:24:56,656 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:24:56,656 INFO L93 Difference]: Finished difference Result 237 states and 268 transitions. [2023-11-23 21:24:56,657 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 9 states. [2023-11-23 21:24:56,657 INFO L78 Accepts]: Start accepts. Automaton has has 10 states, 10 states have (on average 3.0) internal successors, (30), 9 states have internal predecessors, (30), 6 states have call successors, (18), 2 states have call predecessors, (18), 1 states have return successors, (16), 4 states have call predecessors, (16), 4 states have call successors, (16) Word has length 56 [2023-11-23 21:24:56,658 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:24:56,660 INFO L225 Difference]: With dead ends: 237 [2023-11-23 21:24:56,660 INFO L226 Difference]: Without dead ends: 227 [2023-11-23 21:24:56,661 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 170 GetRequests, 143 SyntacticMatches, 3 SemanticMatches, 24 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 138 ImplicationChecksByTransitivity, 1.9s TimeCoverageRelationStatistics Valid=106, Invalid=544, Unknown=0, NotChecked=0, Total=650 [2023-11-23 21:24:56,662 INFO L413 NwaCegarLoop]: 30 mSDtfsCounter, 31 mSDsluCounter, 167 mSDsCounter, 0 mSdLazyCounter, 122 mSolverCounterSat, 35 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.3s Time, 0 mProtectedPredicate, 0 mProtectedAction, 31 SdHoareTripleChecker+Valid, 197 SdHoareTripleChecker+Invalid, 157 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 35 IncrementalHoareTripleChecker+Valid, 122 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.4s IncrementalHoareTripleChecker+Time [2023-11-23 21:24:56,663 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [31 Valid, 197 Invalid, 157 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [35 Valid, 122 Invalid, 0 Unknown, 0 Unchecked, 0.4s Time] [2023-11-23 21:24:56,664 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 227 states. [2023-11-23 21:24:56,730 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 227 to 220. [2023-11-23 21:24:56,731 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 220 states, 145 states have (on average 1.1310344827586207) internal successors, (164), 152 states have internal predecessors, (164), 42 states have call successors, (42), 32 states have call predecessors, (42), 32 states have return successors, (39), 35 states have call predecessors, (39), 39 states have call successors, (39) [2023-11-23 21:24:56,733 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 220 states to 220 states and 245 transitions. [2023-11-23 21:24:56,733 INFO L78 Accepts]: Start accepts. Automaton has 220 states and 245 transitions. Word has length 56 [2023-11-23 21:24:56,734 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:24:56,734 INFO L495 AbstractCegarLoop]: Abstraction has 220 states and 245 transitions. [2023-11-23 21:24:56,734 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 10 states, 10 states have (on average 3.0) internal successors, (30), 9 states have internal predecessors, (30), 6 states have call successors, (18), 2 states have call predecessors, (18), 1 states have return successors, (16), 4 states have call predecessors, (16), 4 states have call successors, (16) [2023-11-23 21:24:56,734 INFO L276 IsEmpty]: Start isEmpty. Operand 220 states and 245 transitions. [2023-11-23 21:24:56,736 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 62 [2023-11-23 21:24:56,736 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:24:56,737 INFO L195 NwaCegarLoop]: trace histogram [10, 9, 9, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:24:56,760 INFO L540 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (10)] Forceful destruction successful, exit code 0 [2023-11-23 21:24:56,951 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable10,10 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:56,951 INFO L420 AbstractCegarLoop]: === Iteration 12 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:24:56,952 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:24:56,952 INFO L85 PathProgramCache]: Analyzing trace with hash -638542057, now seen corresponding path program 2 times [2023-11-23 21:24:56,952 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:24:56,952 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1758552265] [2023-11-23 21:24:56,952 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:24:56,952 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:24:56,962 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:24:56,962 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [1927938025] [2023-11-23 21:24:56,962 INFO L93 rtionOrderModulation]: Changing assertion order to OUTSIDE_LOOP_FIRST2 [2023-11-23 21:24:56,962 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:24:56,963 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:24:56,964 INFO L229 MonitoredProcess]: Starting monitored process 11 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:24:56,972 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (11)] Waiting until timeout for monitored process [2023-11-23 21:24:57,028 INFO L228 tOrderPrioritization]: Assert order OUTSIDE_LOOP_FIRST2 issued 3 check-sat command(s) [2023-11-23 21:24:57,028 INFO L229 tOrderPrioritization]: Conjunction of SSA is unsat [2023-11-23 21:24:57,030 INFO L262 TraceCheckSpWp]: Trace formula consists of 122 conjuncts, 31 conjunts are in the unsatisfiable core [2023-11-23 21:24:57,033 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:24:57,303 INFO L134 CoverageAnalysis]: Checked inductivity of 172 backedges. 26 proven. 26 refuted. 0 times theorem prover too weak. 120 trivial. 0 not checked. [2023-11-23 21:24:57,304 INFO L327 TraceCheckSpWp]: Computing backward predicates... [2023-11-23 21:24:58,961 INFO L134 CoverageAnalysis]: Checked inductivity of 172 backedges. 26 proven. 26 refuted. 0 times theorem prover too weak. 120 trivial. 0 not checked. [2023-11-23 21:24:58,962 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:24:58,962 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1758552265] [2023-11-23 21:24:58,962 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: SMT_SOLVER_CANNOT_INTERPOLATE_INPUT [2023-11-23 21:24:58,962 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1927938025] [2023-11-23 21:24:58,962 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [1927938025] provided 0 perfect and 2 imperfect interpolant sequences [2023-11-23 21:24:58,963 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSifa [544867144] [2023-11-23 21:24:58,965 INFO L159 IcfgInterpreter]: Started Sifa with 18 locations of interest [2023-11-23 21:24:58,966 INFO L166 IcfgInterpreter]: Building call graph [2023-11-23 21:24:58,966 INFO L171 IcfgInterpreter]: Initial procedures are [ULTIMATE.start] [2023-11-23 21:24:58,966 INFO L176 IcfgInterpreter]: Starting interpretation [2023-11-23 21:24:58,967 INFO L197 IcfgInterpreter]: Interpreting procedure ULTIMATE.start with input of size 1 for LOIs [2023-11-23 21:25:01,120 INFO L197 IcfgInterpreter]: Interpreting procedure __VERIFIER_assert with input of size 1 for LOIs [2023-11-23 21:25:01,123 INFO L180 IcfgInterpreter]: Interpretation finished [2023-11-23 21:25:02,242 INFO L133 SifaRunner]: Sifa could not show that error location is unreachable, found '4699#(and (= |__VERIFIER_assert_#in~cond| 0) (= __VERIFIER_assert_~cond 0))' at error location [2023-11-23 21:25:02,243 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: ALGORITHM_FAILED [2023-11-23 21:25:02,243 INFO L185 FreeRefinementEngine]: Found 0 perfect and 2 imperfect interpolant sequences. [2023-11-23 21:25:02,243 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [10, 9] total 16 [2023-11-23 21:25:02,243 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [499289257] [2023-11-23 21:25:02,243 INFO L85 oduleStraightlineAll]: Using 2 imperfect interpolants to construct interpolant automaton [2023-11-23 21:25:02,244 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 16 states [2023-11-23 21:25:02,244 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:25:02,245 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 16 interpolants. [2023-11-23 21:25:02,245 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=112, Invalid=590, Unknown=0, NotChecked=0, Total=702 [2023-11-23 21:25:02,245 INFO L87 Difference]: Start difference. First operand 220 states and 245 transitions. Second operand has 16 states, 16 states have (on average 2.3125) internal successors, (37), 15 states have internal predecessors, (37), 8 states have call successors, (20), 3 states have call predecessors, (20), 2 states have return successors, (18), 6 states have call predecessors, (18), 8 states have call successors, (18) [2023-11-23 21:25:03,343 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:25:03,343 INFO L93 Difference]: Finished difference Result 268 states and 302 transitions. [2023-11-23 21:25:03,343 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 11 states. [2023-11-23 21:25:03,344 INFO L78 Accepts]: Start accepts. Automaton has has 16 states, 16 states have (on average 2.3125) internal successors, (37), 15 states have internal predecessors, (37), 8 states have call successors, (20), 3 states have call predecessors, (20), 2 states have return successors, (18), 6 states have call predecessors, (18), 8 states have call successors, (18) Word has length 61 [2023-11-23 21:25:03,344 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:25:03,346 INFO L225 Difference]: With dead ends: 268 [2023-11-23 21:25:03,346 INFO L226 Difference]: Without dead ends: 235 [2023-11-23 21:25:03,347 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 184 GetRequests, 154 SyntacticMatches, 3 SemanticMatches, 27 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 248 ImplicationChecksByTransitivity, 2.3s TimeCoverageRelationStatistics Valid=135, Invalid=677, Unknown=0, NotChecked=0, Total=812 [2023-11-23 21:25:03,348 INFO L413 NwaCegarLoop]: 25 mSDtfsCounter, 39 mSDsluCounter, 158 mSDsCounter, 0 mSdLazyCounter, 227 mSolverCounterSat, 35 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.3s Time, 0 mProtectedPredicate, 0 mProtectedAction, 48 SdHoareTripleChecker+Valid, 183 SdHoareTripleChecker+Invalid, 262 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 35 IncrementalHoareTripleChecker+Valid, 227 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.4s IncrementalHoareTripleChecker+Time [2023-11-23 21:25:03,348 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [48 Valid, 183 Invalid, 262 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [35 Valid, 227 Invalid, 0 Unknown, 0 Unchecked, 0.4s Time] [2023-11-23 21:25:03,349 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 235 states. [2023-11-23 21:25:03,413 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 235 to 231. [2023-11-23 21:25:03,414 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 231 states, 153 states have (on average 1.1111111111111112) internal successors, (170), 159 states have internal predecessors, (170), 43 states have call successors, (43), 35 states have call predecessors, (43), 34 states have return successors, (39), 36 states have call predecessors, (39), 39 states have call successors, (39) [2023-11-23 21:25:03,416 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 231 states to 231 states and 252 transitions. [2023-11-23 21:25:03,416 INFO L78 Accepts]: Start accepts. Automaton has 231 states and 252 transitions. Word has length 61 [2023-11-23 21:25:03,417 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:25:03,417 INFO L495 AbstractCegarLoop]: Abstraction has 231 states and 252 transitions. [2023-11-23 21:25:03,417 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 16 states, 16 states have (on average 2.3125) internal successors, (37), 15 states have internal predecessors, (37), 8 states have call successors, (20), 3 states have call predecessors, (20), 2 states have return successors, (18), 6 states have call predecessors, (18), 8 states have call successors, (18) [2023-11-23 21:25:03,418 INFO L276 IsEmpty]: Start isEmpty. Operand 231 states and 252 transitions. [2023-11-23 21:25:03,419 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 68 [2023-11-23 21:25:03,419 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:25:03,419 INFO L195 NwaCegarLoop]: trace histogram [11, 10, 10, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:25:03,439 INFO L540 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (11)] Forceful destruction successful, exit code 0 [2023-11-23 21:25:03,630 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable11,11 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:25:03,630 INFO L420 AbstractCegarLoop]: === Iteration 13 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:25:03,630 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:25:03,631 INFO L85 PathProgramCache]: Analyzing trace with hash -143001442, now seen corresponding path program 1 times [2023-11-23 21:25:03,631 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:25:03,631 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1102729137] [2023-11-23 21:25:03,631 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:25:03,631 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:25:03,640 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:25:03,640 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [64508859] [2023-11-23 21:25:03,640 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:25:03,640 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:25:03,641 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:25:03,642 INFO L229 MonitoredProcess]: Starting monitored process 12 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:25:03,645 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (12)] Waiting until timeout for monitored process [2023-11-23 21:25:03,707 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:25:03,709 INFO L262 TraceCheckSpWp]: Trace formula consists of 184 conjuncts, 34 conjunts are in the unsatisfiable core [2023-11-23 21:25:03,712 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:25:04,044 INFO L134 CoverageAnalysis]: Checked inductivity of 211 backedges. 19 proven. 39 refuted. 0 times theorem prover too weak. 153 trivial. 0 not checked. [2023-11-23 21:25:04,044 INFO L327 TraceCheckSpWp]: Computing backward predicates... [2023-11-23 21:25:04,826 INFO L134 CoverageAnalysis]: Checked inductivity of 211 backedges. 19 proven. 39 refuted. 0 times theorem prover too weak. 153 trivial. 0 not checked. [2023-11-23 21:25:04,826 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:25:04,827 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1102729137] [2023-11-23 21:25:04,827 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: SMT_SOLVER_CANNOT_INTERPOLATE_INPUT [2023-11-23 21:25:04,827 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [64508859] [2023-11-23 21:25:04,827 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [64508859] provided 0 perfect and 2 imperfect interpolant sequences [2023-11-23 21:25:04,827 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSifa [556979123] [2023-11-23 21:25:04,836 INFO L159 IcfgInterpreter]: Started Sifa with 19 locations of interest [2023-11-23 21:25:04,836 INFO L166 IcfgInterpreter]: Building call graph [2023-11-23 21:25:04,836 INFO L171 IcfgInterpreter]: Initial procedures are [ULTIMATE.start] [2023-11-23 21:25:04,836 INFO L176 IcfgInterpreter]: Starting interpretation [2023-11-23 21:25:04,837 INFO L197 IcfgInterpreter]: Interpreting procedure ULTIMATE.start with input of size 1 for LOIs [2023-11-23 21:25:06,591 INFO L197 IcfgInterpreter]: Interpreting procedure __VERIFIER_assert with input of size 1 for LOIs [2023-11-23 21:25:06,595 INFO L180 IcfgInterpreter]: Interpretation finished [2023-11-23 21:25:07,829 INFO L133 SifaRunner]: Sifa could not show that error location is unreachable, found '5838#(and (= |__VERIFIER_assert_#in~cond| 0) (= __VERIFIER_assert_~cond 0))' at error location [2023-11-23 21:25:07,830 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: ALGORITHM_FAILED [2023-11-23 21:25:07,830 INFO L185 FreeRefinementEngine]: Found 0 perfect and 2 imperfect interpolant sequences. [2023-11-23 21:25:07,830 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [11, 11] total 19 [2023-11-23 21:25:07,830 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1174867443] [2023-11-23 21:25:07,830 INFO L85 oduleStraightlineAll]: Using 2 imperfect interpolants to construct interpolant automaton [2023-11-23 21:25:07,831 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 19 states [2023-11-23 21:25:07,831 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:25:07,832 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 19 interpolants. [2023-11-23 21:25:07,832 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=150, Invalid=780, Unknown=0, NotChecked=0, Total=930 [2023-11-23 21:25:07,833 INFO L87 Difference]: Start difference. First operand 231 states and 252 transitions. Second operand has 19 states, 17 states have (on average 2.2941176470588234) internal successors, (39), 17 states have internal predecessors, (39), 11 states have call successors, (22), 3 states have call predecessors, (22), 2 states have return successors, (20), 8 states have call predecessors, (20), 9 states have call successors, (20) [2023-11-23 21:25:08,428 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:25:08,428 INFO L93 Difference]: Finished difference Result 253 states and 277 transitions. [2023-11-23 21:25:08,429 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 16 states. [2023-11-23 21:25:08,429 INFO L78 Accepts]: Start accepts. Automaton has has 19 states, 17 states have (on average 2.2941176470588234) internal successors, (39), 17 states have internal predecessors, (39), 11 states have call successors, (22), 3 states have call predecessors, (22), 2 states have return successors, (20), 8 states have call predecessors, (20), 9 states have call successors, (20) Word has length 67 [2023-11-23 21:25:08,430 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:25:08,433 INFO L225 Difference]: With dead ends: 253 [2023-11-23 21:25:08,433 INFO L226 Difference]: Without dead ends: 220 [2023-11-23 21:25:08,434 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 204 GetRequests, 168 SyntacticMatches, 3 SemanticMatches, 33 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 367 ImplicationChecksByTransitivity, 1.7s TimeCoverageRelationStatistics Valid=206, Invalid=984, Unknown=0, NotChecked=0, Total=1190 [2023-11-23 21:25:08,435 INFO L413 NwaCegarLoop]: 25 mSDtfsCounter, 39 mSDsluCounter, 166 mSDsCounter, 0 mSdLazyCounter, 199 mSolverCounterSat, 48 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.2s Time, 0 mProtectedPredicate, 0 mProtectedAction, 40 SdHoareTripleChecker+Valid, 191 SdHoareTripleChecker+Invalid, 247 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 48 IncrementalHoareTripleChecker+Valid, 199 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.3s IncrementalHoareTripleChecker+Time [2023-11-23 21:25:08,436 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [40 Valid, 191 Invalid, 247 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [48 Valid, 199 Invalid, 0 Unknown, 0 Unchecked, 0.3s Time] [2023-11-23 21:25:08,437 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 220 states. [2023-11-23 21:25:08,525 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 220 to 194. [2023-11-23 21:25:08,525 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 194 states, 130 states have (on average 1.123076923076923) internal successors, (146), 132 states have internal predecessors, (146), 35 states have call successors, (35), 29 states have call predecessors, (35), 28 states have return successors, (33), 32 states have call predecessors, (33), 33 states have call successors, (33) [2023-11-23 21:25:08,527 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 194 states to 194 states and 214 transitions. [2023-11-23 21:25:08,527 INFO L78 Accepts]: Start accepts. Automaton has 194 states and 214 transitions. Word has length 67 [2023-11-23 21:25:08,527 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:25:08,528 INFO L495 AbstractCegarLoop]: Abstraction has 194 states and 214 transitions. [2023-11-23 21:25:08,528 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 19 states, 17 states have (on average 2.2941176470588234) internal successors, (39), 17 states have internal predecessors, (39), 11 states have call successors, (22), 3 states have call predecessors, (22), 2 states have return successors, (20), 8 states have call predecessors, (20), 9 states have call successors, (20) [2023-11-23 21:25:08,528 INFO L276 IsEmpty]: Start isEmpty. Operand 194 states and 214 transitions. [2023-11-23 21:25:08,529 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 78 [2023-11-23 21:25:08,529 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:25:08,530 INFO L195 NwaCegarLoop]: trace histogram [13, 12, 12, 3, 3, 3, 3, 3, 3, 3, 3, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-23 21:25:08,556 INFO L552 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (12)] Ended with exit code 0 [2023-11-23 21:25:08,743 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable12,12 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:25:08,743 INFO L420 AbstractCegarLoop]: === Iteration 14 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:25:08,743 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:25:08,744 INFO L85 PathProgramCache]: Analyzing trace with hash -319401384, now seen corresponding path program 1 times [2023-11-23 21:25:08,744 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:25:08,744 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1531934944] [2023-11-23 21:25:08,744 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:25:08,744 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:25:08,752 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:25:08,752 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [1091596144] [2023-11-23 21:25:08,753 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:25:08,753 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:25:08,753 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:25:08,754 INFO L229 MonitoredProcess]: Starting monitored process 13 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:25:08,759 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (13)] Waiting until timeout for monitored process [2023-11-23 21:25:08,816 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-23 21:25:08,818 INFO L262 TraceCheckSpWp]: Trace formula consists of 201 conjuncts, 4 conjunts are in the unsatisfiable core [2023-11-23 21:25:08,820 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:25:08,876 INFO L134 CoverageAnalysis]: Checked inductivity of 306 backedges. 84 proven. 0 refuted. 0 times theorem prover too weak. 222 trivial. 0 not checked. [2023-11-23 21:25:08,877 INFO L323 TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect [2023-11-23 21:25:08,877 INFO L136 FreeRefinementEngine]: Strategy SIFA_TAIPAN found an infeasible trace [2023-11-23 21:25:08,877 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1531934944] [2023-11-23 21:25:08,877 WARN L311 FreeRefinementEngine]: Interpolation failed due to KNOWN_IGNORE: SMT_SOLVER_CANNOT_INTERPOLATE_INPUT [2023-11-23 21:25:08,877 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1091596144] [2023-11-23 21:25:08,877 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [1091596144] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-23 21:25:08,878 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-23 21:25:08,878 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2023-11-23 21:25:08,878 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [715914217] [2023-11-23 21:25:08,879 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-23 21:25:08,879 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 5 states [2023-11-23 21:25:08,880 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2023-11-23 21:25:08,880 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2023-11-23 21:25:08,880 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=10, Invalid=10, Unknown=0, NotChecked=0, Total=20 [2023-11-23 21:25:08,881 INFO L87 Difference]: Start difference. First operand 194 states and 214 transitions. Second operand has 5 states, 5 states have (on average 4.2) internal successors, (21), 5 states have internal predecessors, (21), 4 states have call successors, (13), 2 states have call predecessors, (13), 2 states have return successors, (12), 4 states have call predecessors, (12), 4 states have call successors, (12) [2023-11-23 21:25:08,987 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-23 21:25:08,987 INFO L93 Difference]: Finished difference Result 209 states and 229 transitions. [2023-11-23 21:25:08,988 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2023-11-23 21:25:08,989 INFO L78 Accepts]: Start accepts. Automaton has has 5 states, 5 states have (on average 4.2) internal successors, (21), 5 states have internal predecessors, (21), 4 states have call successors, (13), 2 states have call predecessors, (13), 2 states have return successors, (12), 4 states have call predecessors, (12), 4 states have call successors, (12) Word has length 77 [2023-11-23 21:25:08,989 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-23 21:25:08,990 INFO L225 Difference]: With dead ends: 209 [2023-11-23 21:25:08,990 INFO L226 Difference]: Without dead ends: 189 [2023-11-23 21:25:08,991 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 76 GetRequests, 73 SyntacticMatches, 0 SemanticMatches, 3 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=10, Invalid=10, Unknown=0, NotChecked=0, Total=20 [2023-11-23 21:25:08,992 INFO L413 NwaCegarLoop]: 43 mSDtfsCounter, 12 mSDsluCounter, 50 mSDsCounter, 0 mSdLazyCounter, 28 mSolverCounterSat, 8 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.0s Time, 0 mProtectedPredicate, 0 mProtectedAction, 19 SdHoareTripleChecker+Valid, 93 SdHoareTripleChecker+Invalid, 36 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 8 IncrementalHoareTripleChecker+Valid, 28 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.0s IncrementalHoareTripleChecker+Time [2023-11-23 21:25:08,992 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [19 Valid, 93 Invalid, 36 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [8 Valid, 28 Invalid, 0 Unknown, 0 Unchecked, 0.0s Time] [2023-11-23 21:25:08,993 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 189 states. [2023-11-23 21:25:09,061 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 189 to 186. [2023-11-23 21:25:09,062 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 186 states, 125 states have (on average 1.088) internal successors, (136), 127 states have internal predecessors, (136), 33 states have call successors, (33), 27 states have call predecessors, (33), 27 states have return successors, (32), 31 states have call predecessors, (32), 32 states have call successors, (32) [2023-11-23 21:25:09,063 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 186 states to 186 states and 201 transitions. [2023-11-23 21:25:09,064 INFO L78 Accepts]: Start accepts. Automaton has 186 states and 201 transitions. Word has length 77 [2023-11-23 21:25:09,064 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-23 21:25:09,064 INFO L495 AbstractCegarLoop]: Abstraction has 186 states and 201 transitions. [2023-11-23 21:25:09,065 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 5 states, 5 states have (on average 4.2) internal successors, (21), 5 states have internal predecessors, (21), 4 states have call successors, (13), 2 states have call predecessors, (13), 2 states have return successors, (12), 4 states have call predecessors, (12), 4 states have call successors, (12) [2023-11-23 21:25:09,065 INFO L276 IsEmpty]: Start isEmpty. Operand 186 states and 201 transitions. [2023-11-23 21:25:09,066 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 88 [2023-11-23 21:25:09,067 INFO L187 NwaCegarLoop]: Found error trace [2023-11-23 21:25:09,067 INFO L195 NwaCegarLoop]: trace histogram [14, 13, 13, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 1, 1, 1, 1] [2023-11-23 21:25:09,091 INFO L540 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (13)] Forceful destruction successful, exit code 0 [2023-11-23 21:25:09,272 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 13 /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true,SelfDestructingSolverStorable13 [2023-11-23 21:25:09,273 INFO L420 AbstractCegarLoop]: === Iteration 15 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-23 21:25:09,273 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-23 21:25:09,274 INFO L85 PathProgramCache]: Analyzing trace with hash 1528689375, now seen corresponding path program 3 times [2023-11-23 21:25:09,274 INFO L118 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2023-11-23 21:25:09,275 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [2021698718] [2023-11-23 21:25:09,276 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-23 21:25:09,276 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-23 21:25:09,286 ERROR L246 FreeRefinementEngine]: Caught known exception: Unsupported non-linear arithmetic [2023-11-23 21:25:09,287 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleZ3 [760177435] [2023-11-23 21:25:09,287 INFO L93 rtionOrderModulation]: Changing assertion order to TERMS_WITH_SMALL_CONSTANTS_FIRST [2023-11-23 21:25:09,287 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2023-11-23 21:25:09,287 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 [2023-11-23 21:25:09,288 INFO L229 MonitoredProcess]: Starting monitored process 14 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2023-11-23 21:25:09,292 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_3d2f573b-982e-4cea-a850-8662de9f808f/bin/utaipan-verify-mE87zJ7Ire/z3 -smt2 -in SMTLIB2_COMPLIANT=true (14)] Waiting until timeout for monitored process [2023-11-23 21:25:09,386 INFO L228 tOrderPrioritization]: Assert order TERMS_WITH_SMALL_CONSTANTS_FIRST issued 0 check-sat command(s) [2023-11-23 21:25:09,386 INFO L229 tOrderPrioritization]: Conjunction of SSA is unsat [2023-11-23 21:25:09,389 INFO L262 TraceCheckSpWp]: Trace formula consists of 175 conjuncts, 62 conjunts are in the unsatisfiable core [2023-11-23 21:25:09,393 INFO L285 TraceCheckSpWp]: Computing forward predicates... [2023-11-23 21:25:16,842 INFO L134 CoverageAnalysis]: Checked inductivity of 367 backedges. 128 proven. 53 refuted. 0 times theorem prover too weak. 186 trivial. 0 not checked. [2023-11-23 21:25:16,842 INFO L327 TraceCheckSpWp]: Computing backward predicates...