./Ultimate.py --spec ../sv-benchmarks/c/properties/unreach-call.prp --file ../sv-benchmarks/c/aws-c-common/aws_linked_list_pop_front_harness.i --full-output --architecture 64bit -------------------------------------------------------------------------------- Checking for ERROR reachability Using default analysis Version 798a7b37 Calling Ultimate with: /root/.sdkman/candidates/java/21.0.5-tem/bin/java -Dosgi.configuration.area=/storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/config -Xmx15G -Xms4m -jar /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/plugins/org.eclipse.equinox.launcher_1.6.800.v20240513-1750.jar -data @noDefault -ultimatedata /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data -tc /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/config/AutomizerReach.xml -i ../sv-benchmarks/c/aws-c-common/aws_linked_list_pop_front_harness.i -s /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/config/svcomp-Reach-64bit-Automizer_Default.epf --cacsl2boogietranslator.entry.function main --witnessprinter.witness.directory /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux --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 Automizer --witnessprinter.graph.data.architecture 64bit --witnessprinter.graph.data.programhash 0a45241a50bca97d16f2ca30787e76783488e633dbd3fde1131a60622cf8ee85 --- Real Ultimate output --- This is Ultimate 0.3.0-?-798a7b3-m [2025-03-04 02:58:38,112 INFO L188 SettingsManager]: Resetting all preferences to default values... [2025-03-04 02:58:38,162 INFO L114 SettingsManager]: Loading settings from /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/config/svcomp-Reach-64bit-Automizer_Default.epf [2025-03-04 02:58:38,166 WARN L101 SettingsManager]: Preference file contains the following unknown settings: [2025-03-04 02:58:38,169 WARN L103 SettingsManager]: * de.uni_freiburg.informatik.ultimate.core.Log level for class [2025-03-04 02:58:38,188 INFO L130 SettingsManager]: Preferences different from defaults after loading the file: [2025-03-04 02:58:38,188 INFO L151 SettingsManager]: Preferences of UltimateCore differ from their defaults: [2025-03-04 02:58:38,188 INFO L153 SettingsManager]: * Log level for class=de.uni_freiburg.informatik.ultimate.lib.smtlibutils.quantifier.QuantifierPusher=ERROR; [2025-03-04 02:58:38,188 INFO L151 SettingsManager]: Preferences of Boogie Preprocessor differ from their defaults: [2025-03-04 02:58:38,188 INFO L153 SettingsManager]: * Use memory slicer=true [2025-03-04 02:58:38,189 INFO L151 SettingsManager]: Preferences of Boogie Procedure Inliner differ from their defaults: [2025-03-04 02:58:38,189 INFO L153 SettingsManager]: * Ignore calls to procedures called more than once=ONLY_FOR_SEQUENTIAL_PROGRAMS [2025-03-04 02:58:38,189 INFO L151 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2025-03-04 02:58:38,189 INFO L153 SettingsManager]: * Create parallel compositions if possible=false [2025-03-04 02:58:38,189 INFO L153 SettingsManager]: * Use SBE=true [2025-03-04 02:58:38,189 INFO L151 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2025-03-04 02:58:38,189 INFO L153 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2025-03-04 02:58:38,189 INFO L153 SettingsManager]: * Overapproximate operations on floating types=true [2025-03-04 02:58:38,189 INFO L153 SettingsManager]: * Check division by zero=IGNORE [2025-03-04 02:58:38,189 INFO L153 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2025-03-04 02:58:38,189 INFO L153 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2025-03-04 02:58:38,189 INFO L153 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2025-03-04 02:58:38,189 INFO L153 SettingsManager]: * Check if freed pointer was valid=false [2025-03-04 02:58:38,191 INFO L153 SettingsManager]: * Behaviour of calls to undefined functions=OVERAPPROXIMATE_BEHAVIOUR [2025-03-04 02:58:38,191 INFO L153 SettingsManager]: * Use constant arrays=true [2025-03-04 02:58:38,191 INFO L151 SettingsManager]: Preferences of IcfgBuilder differ from their defaults: [2025-03-04 02:58:38,191 INFO L153 SettingsManager]: * Size of a code block=SequenceOfStatements [2025-03-04 02:58:38,191 INFO L153 SettingsManager]: * Only consider context switches at boundaries of atomic blocks=true [2025-03-04 02:58:38,192 INFO L153 SettingsManager]: * SMT solver=External_DefaultMode [2025-03-04 02:58:38,192 INFO L153 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:4000 [2025-03-04 02:58:38,192 INFO L151 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2025-03-04 02:58:38,192 INFO L153 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2025-03-04 02:58:38,192 INFO L153 SettingsManager]: * Compute procedure contracts=false [2025-03-04 02:58:38,192 INFO L153 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopHeads [2025-03-04 02:58:38,192 INFO L153 SettingsManager]: * Trace refinement strategy=CAMEL [2025-03-04 02:58:38,192 INFO L153 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2025-03-04 02:58:38,192 INFO L153 SettingsManager]: * Apply one-shot large block encoding in concurrent analysis=false [2025-03-04 02:58:38,192 INFO L153 SettingsManager]: * Automaton type used in concurrency analysis=PETRI_NET [2025-03-04 02:58:38,193 INFO L153 SettingsManager]: * Order on configurations for Petri net unfoldings=DBO [2025-03-04 02:58:38,193 INFO L153 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2025-03-04 02:58:38,193 INFO L153 SettingsManager]: * Looper check in Petri net analysis=SEMANTIC 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 -> /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux 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 -> Automizer Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data architecture -> 64bit Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data programhash -> 0a45241a50bca97d16f2ca30787e76783488e633dbd3fde1131a60622cf8ee85 [2025-03-04 02:58:38,399 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2025-03-04 02:58:38,407 INFO L261 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2025-03-04 02:58:38,409 INFO L217 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2025-03-04 02:58:38,410 INFO L270 PluginConnector]: Initializing CDTParser... [2025-03-04 02:58:38,410 INFO L274 PluginConnector]: CDTParser initialized [2025-03-04 02:58:38,411 INFO L431 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../sv-benchmarks/c/aws-c-common/aws_linked_list_pop_front_harness.i [2025-03-04 02:58:39,483 INFO L533 CDTParser]: Created temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/846e53736/e696bed1f7f74c64a0d4771ab7e90739/FLAG2e2139a38 [2025-03-04 02:58:39,903 INFO L384 CDTParser]: Found 1 translation units. [2025-03-04 02:58:39,905 INFO L180 CDTParser]: Scanning /storage/repos/ultimate/releaseScripts/default/sv-benchmarks/c/aws-c-common/aws_linked_list_pop_front_harness.i [2025-03-04 02:58:39,930 INFO L427 CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/846e53736/e696bed1f7f74c64a0d4771ab7e90739/FLAG2e2139a38 [2025-03-04 02:58:40,050 INFO L435 CDTParser]: Successfully deleted /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/846e53736/e696bed1f7f74c64a0d4771ab7e90739 [2025-03-04 02:58:40,052 INFO L299 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2025-03-04 02:58:40,053 INFO L133 ToolchainWalker]: Walking toolchain with 6 elements. [2025-03-04 02:58:40,054 INFO L112 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2025-03-04 02:58:40,054 INFO L270 PluginConnector]: Initializing CACSL2BoogieTranslator... [2025-03-04 02:58:40,057 INFO L274 PluginConnector]: CACSL2BoogieTranslator initialized [2025-03-04 02:58:40,058 INFO L184 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 04.03 02:58:40" (1/1) ... [2025-03-04 02:58:40,058 INFO L204 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@11e42423 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:40, skipping insertion in model container [2025-03-04 02:58:40,058 INFO L184 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 04.03 02:58:40" (1/1) ... [2025-03-04 02:58:40,113 INFO L175 MainTranslator]: Built tables and reachable declarations [2025-03-04 02:58:40,333 WARN L250 ndardFunctionHandler]: Function reach_error is already implemented but we override the implementation for the call at /storage/repos/ultimate/releaseScripts/default/sv-benchmarks/c/aws-c-common/aws_linked_list_pop_front_harness.i[4499,4512] [2025-03-04 02:58:40,340 WARN L250 ndardFunctionHandler]: Function reach_error is already implemented but we override the implementation for the call at /storage/repos/ultimate/releaseScripts/default/sv-benchmarks/c/aws-c-common/aws_linked_list_pop_front_harness.i[4559,4572] [2025-03-04 02:58:40,769 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,770 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,770 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,770 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,771 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,779 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,779 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,781 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,781 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,782 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,783 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,783 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:40,783 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,075 WARN L250 ndardFunctionHandler]: Function reach_error is already implemented but we override the implementation for the call at /storage/repos/ultimate/releaseScripts/default/sv-benchmarks/c/aws-c-common/aws_linked_list_pop_front_harness.i[150662,150675] [2025-03-04 02:58:41,077 INFO L210 PostProcessor]: Analyzing one entry point: main [2025-03-04 02:58:41,087 INFO L200 MainTranslator]: Completed pre-run [2025-03-04 02:58:41,101 WARN L250 ndardFunctionHandler]: Function reach_error is already implemented but we override the implementation for the call at /storage/repos/ultimate/releaseScripts/default/sv-benchmarks/c/aws-c-common/aws_linked_list_pop_front_harness.i[4499,4512] [2025-03-04 02:58:41,101 WARN L250 ndardFunctionHandler]: Function reach_error is already implemented but we override the implementation for the call at /storage/repos/ultimate/releaseScripts/default/sv-benchmarks/c/aws-c-common/aws_linked_list_pop_front_harness.i[4559,4572] [2025-03-04 02:58:41,143 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,144 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,144 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,144 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,147 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,154 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,158 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,158 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,159 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,159 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,160 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,160 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,160 WARN L1731 CHandler]: Possible shadowing of function index [2025-03-04 02:58:41,244 WARN L250 ndardFunctionHandler]: Function reach_error is already implemented but we override the implementation for the call at /storage/repos/ultimate/releaseScripts/default/sv-benchmarks/c/aws-c-common/aws_linked_list_pop_front_harness.i[150662,150675] [2025-03-04 02:58:41,244 INFO L210 PostProcessor]: Analyzing one entry point: main [2025-03-04 02:58:41,411 INFO L204 MainTranslator]: Completed translation [2025-03-04 02:58:41,412 INFO L201 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41 WrapperNode [2025-03-04 02:58:41,412 INFO L131 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2025-03-04 02:58:41,412 INFO L112 PluginConnector]: ------------------------Boogie Procedure Inliner---------------------------- [2025-03-04 02:58:41,413 INFO L270 PluginConnector]: Initializing Boogie Procedure Inliner... [2025-03-04 02:58:41,413 INFO L274 PluginConnector]: Boogie Procedure Inliner initialized [2025-03-04 02:58:41,417 INFO L184 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,463 INFO L184 PluginConnector]: Executing the observer Inliner from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,495 INFO L138 Inliner]: procedures = 668, calls = 1044, calls flagged for inlining = 53, calls inlined = 8, statements flattened = 219 [2025-03-04 02:58:41,495 INFO L131 PluginConnector]: ------------------------ END Boogie Procedure Inliner---------------------------- [2025-03-04 02:58:41,495 INFO L112 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2025-03-04 02:58:41,496 INFO L270 PluginConnector]: Initializing Boogie Preprocessor... [2025-03-04 02:58:41,496 INFO L274 PluginConnector]: Boogie Preprocessor initialized [2025-03-04 02:58:41,502 INFO L184 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,502 INFO L184 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,506 INFO L184 PluginConnector]: Executing the observer MemorySlicer from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,530 INFO L175 MemorySlicer]: Split 43 memory accesses to 3 slices as follows [2, 5, 36]. 84 percent of accesses are in the largest equivalence class. The 7 initializations are split as follows [2, 5, 0]. The 9 writes are split as follows [0, 0, 9]. [2025-03-04 02:58:41,531 INFO L184 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,531 INFO L184 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,544 INFO L184 PluginConnector]: Executing the observer ReplaceArrayAssignments from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,545 INFO L184 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,549 INFO L184 PluginConnector]: Executing the observer LTLStepAnnotator from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,550 INFO L184 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,560 INFO L131 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2025-03-04 02:58:41,561 INFO L112 PluginConnector]: ------------------------IcfgBuilder---------------------------- [2025-03-04 02:58:41,561 INFO L270 PluginConnector]: Initializing IcfgBuilder... [2025-03-04 02:58:41,562 INFO L274 PluginConnector]: IcfgBuilder initialized [2025-03-04 02:58:41,563 INFO L184 PluginConnector]: Executing the observer IcfgBuilderObserver from plugin IcfgBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (1/1) ... [2025-03-04 02:58:41,567 INFO L173 SolverBuilder]: Constructing external solver with command: z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:4000 [2025-03-04 02:58:41,577 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2025-03-04 02:58:41,589 INFO L229 MonitoredProcess]: Starting monitored process 1 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:4000 (exit command is (exit), workingDir is null) [2025-03-04 02:58:41,591 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:4000 (1)] Waiting until timeout for monitored process [2025-03-04 02:58:41,608 INFO L130 BoogieDeclarations]: Found specification of procedure aws_is_mem_zeroed [2025-03-04 02:58:41,609 INFO L138 BoogieDeclarations]: Found implementation of procedure aws_is_mem_zeroed [2025-03-04 02:58:41,609 INFO L130 BoogieDeclarations]: Found specification of procedure aws_linked_list_remove [2025-03-04 02:58:41,609 INFO L138 BoogieDeclarations]: Found implementation of procedure aws_linked_list_remove [2025-03-04 02:58:41,609 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.dealloc [2025-03-04 02:58:41,609 INFO L130 BoogieDeclarations]: Found specification of procedure read~int#0 [2025-03-04 02:58:41,609 INFO L130 BoogieDeclarations]: Found specification of procedure read~int#1 [2025-03-04 02:58:41,609 INFO L130 BoogieDeclarations]: Found specification of procedure read~int#2 [2025-03-04 02:58:41,609 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_assert [2025-03-04 02:58:41,610 INFO L138 BoogieDeclarations]: Found implementation of procedure __VERIFIER_assert [2025-03-04 02:58:41,610 INFO L130 BoogieDeclarations]: Found specification of procedure aws_linked_list_node_next_is_valid [2025-03-04 02:58:41,610 INFO L138 BoogieDeclarations]: Found implementation of procedure aws_linked_list_node_next_is_valid [2025-03-04 02:58:41,610 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.allocOnHeap [2025-03-04 02:58:41,610 INFO L130 BoogieDeclarations]: Found specification of procedure aws_linked_list_is_valid [2025-03-04 02:58:41,610 INFO L138 BoogieDeclarations]: Found implementation of procedure aws_linked_list_is_valid [2025-03-04 02:58:41,610 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.allocInit [2025-03-04 02:58:41,611 INFO L130 BoogieDeclarations]: Found specification of procedure write~$Pointer$#0 [2025-03-04 02:58:41,611 INFO L130 BoogieDeclarations]: Found specification of procedure write~$Pointer$#1 [2025-03-04 02:58:41,611 INFO L130 BoogieDeclarations]: Found specification of procedure write~$Pointer$#2 [2025-03-04 02:58:41,611 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2025-03-04 02:58:41,611 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2025-03-04 02:58:41,611 INFO L130 BoogieDeclarations]: Found specification of procedure aws_linked_list_empty [2025-03-04 02:58:41,611 INFO L138 BoogieDeclarations]: Found implementation of procedure aws_linked_list_empty [2025-03-04 02:58:41,611 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.C_memset#0 [2025-03-04 02:58:41,611 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.C_memset#1 [2025-03-04 02:58:41,611 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.C_memset#2 [2025-03-04 02:58:41,611 INFO L138 BoogieDeclarations]: Found implementation of procedure #Ultimate.C_memset#0 [2025-03-04 02:58:41,611 INFO L138 BoogieDeclarations]: Found implementation of procedure #Ultimate.C_memset#1 [2025-03-04 02:58:41,611 INFO L138 BoogieDeclarations]: Found implementation of procedure #Ultimate.C_memset#2 [2025-03-04 02:58:41,611 INFO L130 BoogieDeclarations]: Found specification of procedure assume_abort_if_not [2025-03-04 02:58:41,611 INFO L138 BoogieDeclarations]: Found implementation of procedure assume_abort_if_not [2025-03-04 02:58:41,612 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.allocOnStack [2025-03-04 02:58:41,612 INFO L130 BoogieDeclarations]: Found specification of procedure read~$Pointer$#0 [2025-03-04 02:58:41,612 INFO L130 BoogieDeclarations]: Found specification of procedure read~$Pointer$#1 [2025-03-04 02:58:41,612 INFO L130 BoogieDeclarations]: Found specification of procedure read~$Pointer$#2 [2025-03-04 02:58:41,612 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~$Pointer$#0 [2025-03-04 02:58:41,612 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~$Pointer$#1 [2025-03-04 02:58:41,612 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~$Pointer$#2 [2025-03-04 02:58:41,612 INFO L130 BoogieDeclarations]: Found specification of procedure nondet_uint64_t [2025-03-04 02:58:41,612 INFO L138 BoogieDeclarations]: Found implementation of procedure nondet_uint64_t [2025-03-04 02:58:41,613 INFO L130 BoogieDeclarations]: Found specification of procedure aws_linked_list_node_prev_is_valid [2025-03-04 02:58:41,613 INFO L138 BoogieDeclarations]: Found implementation of procedure aws_linked_list_node_prev_is_valid [2025-03-04 02:58:41,613 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~int#0 [2025-03-04 02:58:41,613 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~int#1 [2025-03-04 02:58:41,613 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~int#2 [2025-03-04 02:58:41,807 INFO L256 CfgBuilder]: Building ICFG [2025-03-04 02:58:41,809 INFO L286 CfgBuilder]: Building CFG for each procedure with an implementation [2025-03-04 02:58:41,848 INFO L1325 $ProcedureCfgBuilder]: dead code at ProgramPoint L4729: havoc #t~mem317.base, #t~mem317.offset;havoc #t~short318;havoc #t~mem319.base, #t~mem319.offset;havoc #t~mem320.base, #t~mem320.offset;havoc #t~short321; [2025-03-04 02:58:41,880 INFO L1325 $ProcedureCfgBuilder]: dead code at ProgramPoint L266: havoc #t~nondet9; [2025-03-04 02:58:41,924 INFO L1325 $ProcedureCfgBuilder]: dead code at ProgramPoint L4718: havoc #t~mem312.base, #t~mem312.offset;havoc #t~short313;havoc #t~mem314.base, #t~mem314.offset;havoc #t~mem315.base, #t~mem315.offset;havoc #t~short316; [2025-03-04 02:58:42,085 INFO L1325 $ProcedureCfgBuilder]: dead code at ProgramPoint L4700: havoc #t~ret311#1; [2025-03-04 02:58:42,089 INFO L1325 $ProcedureCfgBuilder]: dead code at ProgramPoint L4685: havoc #t~mem302.base, #t~mem302.offset; [2025-03-04 02:58:42,138 INFO L? ?]: Removed 104 outVars from TransFormulas that were not future-live. [2025-03-04 02:58:42,138 INFO L307 CfgBuilder]: Performing block encoding [2025-03-04 02:58:42,147 INFO L331 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2025-03-04 02:58:42,148 INFO L336 CfgBuilder]: Removed 0 assume(true) statements. [2025-03-04 02:58:42,149 INFO L201 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.icfgbuilder CFG 04.03 02:58:42 BoogieIcfgContainer [2025-03-04 02:58:42,149 INFO L131 PluginConnector]: ------------------------ END IcfgBuilder---------------------------- [2025-03-04 02:58:42,150 INFO L112 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2025-03-04 02:58:42,151 INFO L270 PluginConnector]: Initializing TraceAbstraction... [2025-03-04 02:58:42,154 INFO L274 PluginConnector]: TraceAbstraction initialized [2025-03-04 02:58:42,155 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 04.03 02:58:40" (1/3) ... [2025-03-04 02:58:42,155 INFO L204 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@4ca18312 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 04.03 02:58:42, skipping insertion in model container [2025-03-04 02:58:42,155 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.03 02:58:41" (2/3) ... [2025-03-04 02:58:42,156 INFO L204 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@4ca18312 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 04.03 02:58:42, skipping insertion in model container [2025-03-04 02:58:42,157 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.icfgbuilder CFG 04.03 02:58:42" (3/3) ... [2025-03-04 02:58:42,157 INFO L128 eAbstractionObserver]: Analyzing ICFG aws_linked_list_pop_front_harness.i [2025-03-04 02:58:42,167 INFO L216 ceAbstractionStarter]: Automizer settings: Hoare:LoopHeads NWA Interpolation:FPandBP Determinization: PREDICATE_ABSTRACTION [2025-03-04 02:58:42,169 INFO L151 ceAbstractionStarter]: Applying trace abstraction to ICFG aws_linked_list_pop_front_harness.i that has 13 procedures, 142 locations, 1 initial locations, 7 loop locations, and 1 error locations. [2025-03-04 02:58:42,212 INFO L332 AbstractCegarLoop]: ======== Iteration 0 == of CEGAR loop == AllErrorsAtOnce ======== [2025-03-04 02:58:42,219 INFO L333 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, mAutomataTypeConcurrency=PETRI_NET, 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;@7a393b2b, mLbeIndependenceSettings=[IndependenceType=SEMANTIC, AbstractionType=NONE, UseConditional=false, UseSemiCommutativity=true, Solver=Z3, SolverTimeout=1000ms] [2025-03-04 02:58:42,221 INFO L334 AbstractCegarLoop]: Starting to check reachability of 1 error locations. [2025-03-04 02:58:42,225 INFO L276 IsEmpty]: Start isEmpty. Operand has 134 states, 86 states have (on average 1.2790697674418605) internal successors, (110), 87 states have internal predecessors, (110), 37 states have call successors, (37), 10 states have call predecessors, (37), 10 states have return successors, (37), 37 states have call predecessors, (37), 37 states have call successors, (37) [2025-03-04 02:58:42,232 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 119 [2025-03-04 02:58:42,233 INFO L210 NwaCegarLoop]: Found error trace [2025-03-04 02:58:42,234 INFO L218 NwaCegarLoop]: trace histogram [9, 9, 9, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2025-03-04 02:58:42,234 INFO L396 AbstractCegarLoop]: === Iteration 1 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2025-03-04 02:58:42,237 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2025-03-04 02:58:42,238 INFO L85 PathProgramCache]: Analyzing trace with hash -1741125493, now seen corresponding path program 1 times [2025-03-04 02:58:42,243 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2025-03-04 02:58:42,243 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1070589752] [2025-03-04 02:58:42,243 INFO L97 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2025-03-04 02:58:42,243 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2025-03-04 02:58:42,344 INFO L108 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY partitioned 118 statements into 1 equivalence classes. [2025-03-04 02:58:42,455 INFO L111 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) and asserted 118 of 118 statements. [2025-03-04 02:58:42,456 INFO L114 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) [2025-03-04 02:58:42,456 INFO L115 AnnotateAndAsserter]: Conjunction of SSA is unsat [2025-03-04 02:58:43,061 INFO L134 CoverageAnalysis]: Checked inductivity of 195 backedges. 20 proven. 8 refuted. 0 times theorem prover too weak. 167 trivial. 0 not checked. [2025-03-04 02:58:43,062 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2025-03-04 02:58:43,063 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1070589752] [2025-03-04 02:58:43,063 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1070589752] provided 0 perfect and 1 imperfect interpolant sequences [2025-03-04 02:58:43,064 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1656949098] [2025-03-04 02:58:43,064 INFO L97 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2025-03-04 02:58:43,064 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2025-03-04 02:58:43,064 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2025-03-04 02:58:43,066 INFO L229 MonitoredProcess]: Starting monitored process 2 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2025-03-04 02:58:43,067 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (2)] Waiting until timeout for monitored process [2025-03-04 02:58:43,183 INFO L108 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY partitioned 118 statements into 1 equivalence classes. [2025-03-04 02:58:43,247 INFO L111 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) and asserted 118 of 118 statements. [2025-03-04 02:58:43,247 INFO L114 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) [2025-03-04 02:58:43,247 INFO L115 AnnotateAndAsserter]: Conjunction of SSA is unsat [2025-03-04 02:58:43,251 INFO L256 TraceCheckSpWp]: Trace formula consists of 443 conjuncts, 89 conjuncts are in the unsatisfiable core [2025-03-04 02:58:43,263 INFO L279 TraceCheckSpWp]: Computing forward predicates... [2025-03-04 02:58:43,393 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 1 stores, 0 select indices, 0 select index equivalence classes, 2 disjoint index pairs (out of 0 index pairs), introduced 0 new quantified variables, introduced 0 case distinctions, treesize of input 14 treesize of output 15 [2025-03-04 02:58:43,402 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 1 stores, 0 select indices, 0 select index equivalence classes, 1 disjoint index pairs (out of 0 index pairs), introduced 0 new quantified variables, introduced 0 case distinctions, treesize of input 14 treesize of output 15 [2025-03-04 02:58:44,234 INFO L349 Elim1Store]: treesize reduction 16, result has 5.9 percent of original size [2025-03-04 02:58:44,234 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 0 stores, 4 select indices, 4 select index equivalence classes, 1 disjoint index pairs (out of 6 index pairs), introduced 4 new quantified variables, introduced 4 case distinctions, treesize of input 29 treesize of output 13 [2025-03-04 02:58:44,241 INFO L349 Elim1Store]: treesize reduction 16, result has 5.9 percent of original size [2025-03-04 02:58:44,242 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 0 stores, 4 select indices, 4 select index equivalence classes, 1 disjoint index pairs (out of 6 index pairs), introduced 4 new quantified variables, introduced 4 case distinctions, treesize of input 29 treesize of output 13 [2025-03-04 02:58:44,283 INFO L134 CoverageAnalysis]: Checked inductivity of 195 backedges. 105 proven. 12 refuted. 0 times theorem prover too weak. 78 trivial. 0 not checked. [2025-03-04 02:58:44,285 INFO L312 TraceCheckSpWp]: Computing backward predicates... [2025-03-04 02:58:44,736 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 0 stores, 1 select indices, 1 select index equivalence classes, 0 disjoint index pairs (out of 0 index pairs), introduced 1 new quantified variables, introduced 0 case distinctions, treesize of input 164 treesize of output 156 [2025-03-04 02:58:44,763 INFO L190 IndexEqualityManager]: detected not equals via solver [2025-03-04 02:58:44,765 INFO L190 IndexEqualityManager]: detected not equals via solver [2025-03-04 02:58:44,767 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 0 stores, 1 select indices, 1 select index equivalence classes, 0 disjoint index pairs (out of 0 index pairs), introduced 1 new quantified variables, introduced 0 case distinctions, treesize of input 60 treesize of output 56 [2025-03-04 02:58:44,852 INFO L134 CoverageAnalysis]: Checked inductivity of 195 backedges. 16 proven. 16 refuted. 0 times theorem prover too weak. 163 trivial. 0 not checked. [2025-03-04 02:58:44,852 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [1656949098] provided 0 perfect and 2 imperfect interpolant sequences [2025-03-04 02:58:44,852 INFO L185 FreeRefinementEngine]: Found 0 perfect and 3 imperfect interpolant sequences. [2025-03-04 02:58:44,852 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [6, 13, 13] total 26 [2025-03-04 02:58:44,854 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [52995015] [2025-03-04 02:58:44,854 INFO L85 oduleStraightlineAll]: Using 3 imperfect interpolants to construct interpolant automaton [2025-03-04 02:58:44,857 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 26 states [2025-03-04 02:58:44,857 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2025-03-04 02:58:44,868 INFO L144 InterpolantAutomaton]: Constructing interpolant automaton starting with 26 interpolants. [2025-03-04 02:58:44,869 INFO L146 InterpolantAutomaton]: CoverageRelationStatistics Valid=66, Invalid=584, Unknown=0, NotChecked=0, Total=650 [2025-03-04 02:58:44,870 INFO L87 Difference]: Start difference. First operand has 134 states, 86 states have (on average 1.2790697674418605) internal successors, (110), 87 states have internal predecessors, (110), 37 states have call successors, (37), 10 states have call predecessors, (37), 10 states have return successors, (37), 37 states have call predecessors, (37), 37 states have call successors, (37) Second operand has 26 states, 21 states have (on average 4.0476190476190474) internal successors, (85), 22 states have internal predecessors, (85), 13 states have call successors, (42), 4 states have call predecessors, (42), 8 states have return successors, (40), 11 states have call predecessors, (40), 13 states have call successors, (40) [2025-03-04 02:58:45,900 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2025-03-04 02:58:45,901 INFO L93 Difference]: Finished difference Result 279 states and 418 transitions. [2025-03-04 02:58:45,902 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 19 states. [2025-03-04 02:58:45,903 INFO L78 Accepts]: Start accepts. Automaton has has 26 states, 21 states have (on average 4.0476190476190474) internal successors, (85), 22 states have internal predecessors, (85), 13 states have call successors, (42), 4 states have call predecessors, (42), 8 states have return successors, (40), 11 states have call predecessors, (40), 13 states have call successors, (40) Word has length 118 [2025-03-04 02:58:45,903 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2025-03-04 02:58:45,908 INFO L225 Difference]: With dead ends: 279 [2025-03-04 02:58:45,908 INFO L226 Difference]: Without dead ends: 132 [2025-03-04 02:58:45,911 INFO L434 NwaCegarLoop]: 0 DeclaredPredicates, 257 GetRequests, 213 SyntacticMatches, 4 SemanticMatches, 40 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 279 ImplicationChecksByTransitivity, 0.9s TimeCoverageRelationStatistics Valid=173, Invalid=1549, Unknown=0, NotChecked=0, Total=1722 [2025-03-04 02:58:45,912 INFO L435 NwaCegarLoop]: 161 mSDtfsCounter, 174 mSDsluCounter, 2632 mSDsCounter, 0 mSdLazyCounter, 659 mSolverCounterSat, 19 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.5s Time, 0 mProtectedPredicate, 0 mProtectedAction, 190 SdHoareTripleChecker+Valid, 2793 SdHoareTripleChecker+Invalid, 678 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 19 IncrementalHoareTripleChecker+Valid, 659 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.6s IncrementalHoareTripleChecker+Time [2025-03-04 02:58:45,913 INFO L436 NwaCegarLoop]: SdHoareTripleChecker [190 Valid, 2793 Invalid, 678 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [19 Valid, 659 Invalid, 0 Unknown, 0 Unchecked, 0.6s Time] [2025-03-04 02:58:45,922 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 132 states. [2025-03-04 02:58:45,939 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 132 to 132. [2025-03-04 02:58:45,940 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 132 states, 83 states have (on average 1.2530120481927711) internal successors, (104), 85 states have internal predecessors, (104), 37 states have call successors, (37), 10 states have call predecessors, (37), 11 states have return successors, (40), 36 states have call predecessors, (40), 36 states have call successors, (40) [2025-03-04 02:58:45,944 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 132 states to 132 states and 181 transitions. [2025-03-04 02:58:45,946 INFO L78 Accepts]: Start accepts. Automaton has 132 states and 181 transitions. Word has length 118 [2025-03-04 02:58:45,947 INFO L84 Accepts]: Finished accepts. word is rejected. [2025-03-04 02:58:45,947 INFO L471 AbstractCegarLoop]: Abstraction has 132 states and 181 transitions. [2025-03-04 02:58:45,947 INFO L472 AbstractCegarLoop]: INTERPOLANT automaton has has 26 states, 21 states have (on average 4.0476190476190474) internal successors, (85), 22 states have internal predecessors, (85), 13 states have call successors, (42), 4 states have call predecessors, (42), 8 states have return successors, (40), 11 states have call predecessors, (40), 13 states have call successors, (40) [2025-03-04 02:58:45,947 INFO L276 IsEmpty]: Start isEmpty. Operand 132 states and 181 transitions. [2025-03-04 02:58:45,949 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 121 [2025-03-04 02:58:45,949 INFO L210 NwaCegarLoop]: Found error trace [2025-03-04 02:58:45,950 INFO L218 NwaCegarLoop]: trace histogram [9, 9, 9, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2025-03-04 02:58:45,957 INFO L552 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (2)] Ended with exit code 0 [2025-03-04 02:58:46,150 WARN L453 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 2 /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true,SelfDestructingSolverStorable0 [2025-03-04 02:58:46,150 INFO L396 AbstractCegarLoop]: === Iteration 2 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2025-03-04 02:58:46,151 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2025-03-04 02:58:46,151 INFO L85 PathProgramCache]: Analyzing trace with hash -791596319, now seen corresponding path program 1 times [2025-03-04 02:58:46,151 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2025-03-04 02:58:46,151 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [408857655] [2025-03-04 02:58:46,151 INFO L97 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2025-03-04 02:58:46,151 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2025-03-04 02:58:46,181 INFO L108 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY partitioned 120 statements into 1 equivalence classes. [2025-03-04 02:58:46,200 INFO L111 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) and asserted 120 of 120 statements. [2025-03-04 02:58:46,200 INFO L114 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) [2025-03-04 02:58:46,200 INFO L115 AnnotateAndAsserter]: Conjunction of SSA is unsat [2025-03-04 02:58:46,457 INFO L134 CoverageAnalysis]: Checked inductivity of 194 backedges. 10 proven. 10 refuted. 0 times theorem prover too weak. 174 trivial. 0 not checked. [2025-03-04 02:58:46,457 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2025-03-04 02:58:46,457 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [408857655] [2025-03-04 02:58:46,457 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [408857655] provided 0 perfect and 1 imperfect interpolant sequences [2025-03-04 02:58:46,457 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [2133283907] [2025-03-04 02:58:46,457 INFO L97 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2025-03-04 02:58:46,458 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2025-03-04 02:58:46,458 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2025-03-04 02:58:46,461 INFO L229 MonitoredProcess]: Starting monitored process 3 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2025-03-04 02:58:46,462 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (3)] Waiting until timeout for monitored process [2025-03-04 02:58:46,561 INFO L108 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY partitioned 120 statements into 1 equivalence classes. [2025-03-04 02:58:46,611 INFO L111 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) and asserted 120 of 120 statements. [2025-03-04 02:58:46,612 INFO L114 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) [2025-03-04 02:58:46,612 INFO L115 AnnotateAndAsserter]: Conjunction of SSA is unsat [2025-03-04 02:58:46,614 INFO L256 TraceCheckSpWp]: Trace formula consists of 502 conjuncts, 11 conjuncts are in the unsatisfiable core [2025-03-04 02:58:46,619 INFO L279 TraceCheckSpWp]: Computing forward predicates... [2025-03-04 02:58:46,708 INFO L134 CoverageAnalysis]: Checked inductivity of 194 backedges. 115 proven. 0 refuted. 0 times theorem prover too weak. 79 trivial. 0 not checked. [2025-03-04 02:58:46,709 INFO L308 TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect [2025-03-04 02:58:46,709 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [2133283907] provided 1 perfect and 0 imperfect interpolant sequences [2025-03-04 02:58:46,709 INFO L185 FreeRefinementEngine]: Found 1 perfect and 1 imperfect interpolant sequences. [2025-03-04 02:58:46,709 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [9] imperfect sequences [8] total 15 [2025-03-04 02:58:46,709 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1571422409] [2025-03-04 02:58:46,709 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2025-03-04 02:58:46,710 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 9 states [2025-03-04 02:58:46,710 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2025-03-04 02:58:46,711 INFO L144 InterpolantAutomaton]: Constructing interpolant automaton starting with 9 interpolants. [2025-03-04 02:58:46,711 INFO L146 InterpolantAutomaton]: CoverageRelationStatistics Valid=33, Invalid=177, Unknown=0, NotChecked=0, Total=210 [2025-03-04 02:58:46,711 INFO L87 Difference]: Start difference. First operand 132 states and 181 transitions. Second operand has 9 states, 8 states have (on average 7.875) internal successors, (63), 9 states have internal predecessors, (63), 5 states have call successors, (16), 2 states have call predecessors, (16), 3 states have return successors, (15), 4 states have call predecessors, (15), 5 states have call successors, (15) [2025-03-04 02:58:46,966 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2025-03-04 02:58:46,967 INFO L93 Difference]: Finished difference Result 250 states and 344 transitions. [2025-03-04 02:58:46,967 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 9 states. [2025-03-04 02:58:46,967 INFO L78 Accepts]: Start accepts. Automaton has has 9 states, 8 states have (on average 7.875) internal successors, (63), 9 states have internal predecessors, (63), 5 states have call successors, (16), 2 states have call predecessors, (16), 3 states have return successors, (15), 4 states have call predecessors, (15), 5 states have call successors, (15) Word has length 120 [2025-03-04 02:58:46,967 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2025-03-04 02:58:46,969 INFO L225 Difference]: With dead ends: 250 [2025-03-04 02:58:46,969 INFO L226 Difference]: Without dead ends: 134 [2025-03-04 02:58:46,970 INFO L434 NwaCegarLoop]: 0 DeclaredPredicates, 135 GetRequests, 116 SyntacticMatches, 0 SemanticMatches, 19 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 39 ImplicationChecksByTransitivity, 0.1s TimeCoverageRelationStatistics Valid=69, Invalid=351, Unknown=0, NotChecked=0, Total=420 [2025-03-04 02:58:46,970 INFO L435 NwaCegarLoop]: 136 mSDtfsCounter, 202 mSDsluCounter, 744 mSDsCounter, 0 mSdLazyCounter, 235 mSolverCounterSat, 88 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.2s Time, 0 mProtectedPredicate, 0 mProtectedAction, 202 SdHoareTripleChecker+Valid, 880 SdHoareTripleChecker+Invalid, 323 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 88 IncrementalHoareTripleChecker+Valid, 235 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.2s IncrementalHoareTripleChecker+Time [2025-03-04 02:58:46,971 INFO L436 NwaCegarLoop]: SdHoareTripleChecker [202 Valid, 880 Invalid, 323 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [88 Valid, 235 Invalid, 0 Unknown, 0 Unchecked, 0.2s Time] [2025-03-04 02:58:46,971 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 134 states. [2025-03-04 02:58:46,980 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 134 to 132. [2025-03-04 02:58:46,981 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 132 states, 83 states have (on average 1.2409638554216869) internal successors, (103), 85 states have internal predecessors, (103), 37 states have call successors, (37), 10 states have call predecessors, (37), 11 states have return successors, (40), 36 states have call predecessors, (40), 36 states have call successors, (40) [2025-03-04 02:58:46,984 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 132 states to 132 states and 180 transitions. [2025-03-04 02:58:46,984 INFO L78 Accepts]: Start accepts. Automaton has 132 states and 180 transitions. Word has length 120 [2025-03-04 02:58:46,985 INFO L84 Accepts]: Finished accepts. word is rejected. [2025-03-04 02:58:46,985 INFO L471 AbstractCegarLoop]: Abstraction has 132 states and 180 transitions. [2025-03-04 02:58:46,985 INFO L472 AbstractCegarLoop]: INTERPOLANT automaton has has 9 states, 8 states have (on average 7.875) internal successors, (63), 9 states have internal predecessors, (63), 5 states have call successors, (16), 2 states have call predecessors, (16), 3 states have return successors, (15), 4 states have call predecessors, (15), 5 states have call successors, (15) [2025-03-04 02:58:46,985 INFO L276 IsEmpty]: Start isEmpty. Operand 132 states and 180 transitions. [2025-03-04 02:58:46,986 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 123 [2025-03-04 02:58:46,986 INFO L210 NwaCegarLoop]: Found error trace [2025-03-04 02:58:46,986 INFO L218 NwaCegarLoop]: trace histogram [9, 9, 9, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2025-03-04 02:58:46,993 INFO L552 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (3)] Ended with exit code 0 [2025-03-04 02:58:47,186 WARN L453 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 3 /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true,SelfDestructingSolverStorable1 [2025-03-04 02:58:47,187 INFO L396 AbstractCegarLoop]: === Iteration 3 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2025-03-04 02:58:47,188 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2025-03-04 02:58:47,189 INFO L85 PathProgramCache]: Analyzing trace with hash 1616401305, now seen corresponding path program 1 times [2025-03-04 02:58:47,189 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2025-03-04 02:58:47,189 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [356319429] [2025-03-04 02:58:47,189 INFO L97 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2025-03-04 02:58:47,189 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2025-03-04 02:58:47,210 INFO L108 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY partitioned 122 statements into 1 equivalence classes. [2025-03-04 02:58:47,224 INFO L111 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) and asserted 122 of 122 statements. [2025-03-04 02:58:47,224 INFO L114 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) [2025-03-04 02:58:47,224 INFO L115 AnnotateAndAsserter]: Conjunction of SSA is unsat [2025-03-04 02:58:47,471 INFO L134 CoverageAnalysis]: Checked inductivity of 194 backedges. 10 proven. 10 refuted. 0 times theorem prover too weak. 174 trivial. 0 not checked. [2025-03-04 02:58:47,472 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2025-03-04 02:58:47,472 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [356319429] [2025-03-04 02:58:47,472 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [356319429] provided 0 perfect and 1 imperfect interpolant sequences [2025-03-04 02:58:47,472 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [46689845] [2025-03-04 02:58:47,472 INFO L97 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2025-03-04 02:58:47,472 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2025-03-04 02:58:47,472 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2025-03-04 02:58:47,474 INFO L229 MonitoredProcess]: Starting monitored process 4 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2025-03-04 02:58:47,476 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (4)] Waiting until timeout for monitored process [2025-03-04 02:58:47,574 INFO L108 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY partitioned 122 statements into 1 equivalence classes. [2025-03-04 02:58:47,621 INFO L111 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) and asserted 122 of 122 statements. [2025-03-04 02:58:47,621 INFO L114 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) [2025-03-04 02:58:47,621 INFO L115 AnnotateAndAsserter]: Conjunction of SSA is unsat [2025-03-04 02:58:47,625 INFO L256 TraceCheckSpWp]: Trace formula consists of 509 conjuncts, 12 conjuncts are in the unsatisfiable core [2025-03-04 02:58:47,628 INFO L279 TraceCheckSpWp]: Computing forward predicates... [2025-03-04 02:58:47,734 INFO L134 CoverageAnalysis]: Checked inductivity of 194 backedges. 115 proven. 0 refuted. 0 times theorem prover too weak. 79 trivial. 0 not checked. [2025-03-04 02:58:47,734 INFO L308 TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect [2025-03-04 02:58:47,734 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [46689845] provided 1 perfect and 0 imperfect interpolant sequences [2025-03-04 02:58:47,734 INFO L185 FreeRefinementEngine]: Found 1 perfect and 1 imperfect interpolant sequences. [2025-03-04 02:58:47,734 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [10] imperfect sequences [9] total 17 [2025-03-04 02:58:47,735 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [2040970260] [2025-03-04 02:58:47,735 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2025-03-04 02:58:47,735 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 10 states [2025-03-04 02:58:47,735 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2025-03-04 02:58:47,735 INFO L144 InterpolantAutomaton]: Constructing interpolant automaton starting with 10 interpolants. [2025-03-04 02:58:47,736 INFO L146 InterpolantAutomaton]: CoverageRelationStatistics Valid=32, Invalid=240, Unknown=0, NotChecked=0, Total=272 [2025-03-04 02:58:47,736 INFO L87 Difference]: Start difference. First operand 132 states and 180 transitions. Second operand has 10 states, 9 states have (on average 7.222222222222222) internal successors, (65), 10 states have internal predecessors, (65), 5 states have call successors, (16), 2 states have call predecessors, (16), 3 states have return successors, (15), 4 states have call predecessors, (15), 5 states have call successors, (15) [2025-03-04 02:58:48,028 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2025-03-04 02:58:48,028 INFO L93 Difference]: Finished difference Result 256 states and 352 transitions. [2025-03-04 02:58:48,029 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 11 states. [2025-03-04 02:58:48,029 INFO L78 Accepts]: Start accepts. Automaton has has 10 states, 9 states have (on average 7.222222222222222) internal successors, (65), 10 states have internal predecessors, (65), 5 states have call successors, (16), 2 states have call predecessors, (16), 3 states have return successors, (15), 4 states have call predecessors, (15), 5 states have call successors, (15) Word has length 122 [2025-03-04 02:58:48,029 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2025-03-04 02:58:48,030 INFO L225 Difference]: With dead ends: 256 [2025-03-04 02:58:48,030 INFO L226 Difference]: Without dead ends: 139 [2025-03-04 02:58:48,031 INFO L434 NwaCegarLoop]: 0 DeclaredPredicates, 140 GetRequests, 117 SyntacticMatches, 0 SemanticMatches, 23 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 39 ImplicationChecksByTransitivity, 0.2s TimeCoverageRelationStatistics Valid=75, Invalid=525, Unknown=0, NotChecked=0, Total=600 [2025-03-04 02:58:48,032 INFO L435 NwaCegarLoop]: 133 mSDtfsCounter, 216 mSDsluCounter, 857 mSDsCounter, 0 mSdLazyCounter, 296 mSolverCounterSat, 91 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.2s Time, 0 mProtectedPredicate, 0 mProtectedAction, 216 SdHoareTripleChecker+Valid, 990 SdHoareTripleChecker+Invalid, 387 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 91 IncrementalHoareTripleChecker+Valid, 296 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.2s IncrementalHoareTripleChecker+Time [2025-03-04 02:58:48,032 INFO L436 NwaCegarLoop]: SdHoareTripleChecker [216 Valid, 990 Invalid, 387 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [91 Valid, 296 Invalid, 0 Unknown, 0 Unchecked, 0.2s Time] [2025-03-04 02:58:48,032 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 139 states. [2025-03-04 02:58:48,046 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 139 to 133. [2025-03-04 02:58:48,047 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 133 states, 84 states have (on average 1.2380952380952381) internal successors, (104), 86 states have internal predecessors, (104), 37 states have call successors, (37), 10 states have call predecessors, (37), 11 states have return successors, (40), 36 states have call predecessors, (40), 36 states have call successors, (40) [2025-03-04 02:58:48,048 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 133 states to 133 states and 181 transitions. [2025-03-04 02:58:48,048 INFO L78 Accepts]: Start accepts. Automaton has 133 states and 181 transitions. Word has length 122 [2025-03-04 02:58:48,048 INFO L84 Accepts]: Finished accepts. word is rejected. [2025-03-04 02:58:48,048 INFO L471 AbstractCegarLoop]: Abstraction has 133 states and 181 transitions. [2025-03-04 02:58:48,048 INFO L472 AbstractCegarLoop]: INTERPOLANT automaton has has 10 states, 9 states have (on average 7.222222222222222) internal successors, (65), 10 states have internal predecessors, (65), 5 states have call successors, (16), 2 states have call predecessors, (16), 3 states have return successors, (15), 4 states have call predecessors, (15), 5 states have call successors, (15) [2025-03-04 02:58:48,048 INFO L276 IsEmpty]: Start isEmpty. Operand 133 states and 181 transitions. [2025-03-04 02:58:48,049 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 124 [2025-03-04 02:58:48,050 INFO L210 NwaCegarLoop]: Found error trace [2025-03-04 02:58:48,050 INFO L218 NwaCegarLoop]: trace histogram [9, 9, 9, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2025-03-04 02:58:48,056 INFO L552 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (4)] Ended with exit code 0 [2025-03-04 02:58:48,254 WARN L453 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable2,4 /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2025-03-04 02:58:48,254 INFO L396 AbstractCegarLoop]: === Iteration 4 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2025-03-04 02:58:48,254 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2025-03-04 02:58:48,254 INFO L85 PathProgramCache]: Analyzing trace with hash -615611050, now seen corresponding path program 1 times [2025-03-04 02:58:48,254 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2025-03-04 02:58:48,255 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [860030784] [2025-03-04 02:58:48,255 INFO L97 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2025-03-04 02:58:48,255 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2025-03-04 02:58:48,272 INFO L108 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY partitioned 123 statements into 1 equivalence classes. [2025-03-04 02:58:48,280 INFO L111 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) and asserted 123 of 123 statements. [2025-03-04 02:58:48,281 INFO L114 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) [2025-03-04 02:58:48,281 INFO L115 AnnotateAndAsserter]: Conjunction of SSA is unsat [2025-03-04 02:58:48,568 INFO L134 CoverageAnalysis]: Checked inductivity of 194 backedges. 10 proven. 10 refuted. 0 times theorem prover too weak. 174 trivial. 0 not checked. [2025-03-04 02:58:48,568 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2025-03-04 02:58:48,568 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [860030784] [2025-03-04 02:58:48,569 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [860030784] provided 0 perfect and 1 imperfect interpolant sequences [2025-03-04 02:58:48,569 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1715463918] [2025-03-04 02:58:48,569 INFO L97 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2025-03-04 02:58:48,569 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2025-03-04 02:58:48,569 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2025-03-04 02:58:48,571 INFO L229 MonitoredProcess]: Starting monitored process 5 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2025-03-04 02:58:48,573 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (5)] Waiting until timeout for monitored process [2025-03-04 02:58:48,683 INFO L108 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY partitioned 123 statements into 1 equivalence classes. [2025-03-04 02:58:48,727 INFO L111 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) and asserted 123 of 123 statements. [2025-03-04 02:58:48,728 INFO L114 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) [2025-03-04 02:58:48,728 INFO L115 AnnotateAndAsserter]: Conjunction of SSA is unsat [2025-03-04 02:58:48,730 INFO L256 TraceCheckSpWp]: Trace formula consists of 512 conjuncts, 2 conjuncts are in the unsatisfiable core [2025-03-04 02:58:48,734 INFO L279 TraceCheckSpWp]: Computing forward predicates... [2025-03-04 02:58:48,748 INFO L134 CoverageAnalysis]: Checked inductivity of 194 backedges. 105 proven. 0 refuted. 0 times theorem prover too weak. 89 trivial. 0 not checked. [2025-03-04 02:58:48,748 INFO L308 TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect [2025-03-04 02:58:48,748 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [1715463918] provided 1 perfect and 0 imperfect interpolant sequences [2025-03-04 02:58:48,748 INFO L185 FreeRefinementEngine]: Found 1 perfect and 1 imperfect interpolant sequences. [2025-03-04 02:58:48,748 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [3] imperfect sequences [9] total 10 [2025-03-04 02:58:48,749 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [2112235886] [2025-03-04 02:58:48,749 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2025-03-04 02:58:48,749 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 3 states [2025-03-04 02:58:48,749 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2025-03-04 02:58:48,749 INFO L144 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2025-03-04 02:58:48,750 INFO L146 InterpolantAutomaton]: CoverageRelationStatistics Valid=17, Invalid=73, Unknown=0, NotChecked=0, Total=90 [2025-03-04 02:58:48,750 INFO L87 Difference]: Start difference. First operand 133 states and 181 transitions. Second operand has 3 states, 3 states have (on average 19.0) internal successors, (57), 3 states have internal predecessors, (57), 2 states have call successors, (16), 2 states have call predecessors, (16), 2 states have return successors, (15), 2 states have call predecessors, (15), 2 states have call successors, (15) [2025-03-04 02:58:48,763 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2025-03-04 02:58:48,763 INFO L93 Difference]: Finished difference Result 251 states and 347 transitions. [2025-03-04 02:58:48,764 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 3 states. [2025-03-04 02:58:48,764 INFO L78 Accepts]: Start accepts. Automaton has has 3 states, 3 states have (on average 19.0) internal successors, (57), 3 states have internal predecessors, (57), 2 states have call successors, (16), 2 states have call predecessors, (16), 2 states have return successors, (15), 2 states have call predecessors, (15), 2 states have call successors, (15) Word has length 123 [2025-03-04 02:58:48,764 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2025-03-04 02:58:48,765 INFO L225 Difference]: With dead ends: 251 [2025-03-04 02:58:48,766 INFO L226 Difference]: Without dead ends: 137 [2025-03-04 02:58:48,766 INFO L434 NwaCegarLoop]: 0 DeclaredPredicates, 131 GetRequests, 123 SyntacticMatches, 0 SemanticMatches, 8 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=17, Invalid=73, Unknown=0, NotChecked=0, Total=90 [2025-03-04 02:58:48,767 INFO L435 NwaCegarLoop]: 171 mSDtfsCounter, 2 mSDsluCounter, 166 mSDsCounter, 0 mSdLazyCounter, 10 mSolverCounterSat, 0 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.0s Time, 0 mProtectedPredicate, 0 mProtectedAction, 3 SdHoareTripleChecker+Valid, 337 SdHoareTripleChecker+Invalid, 10 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 0 IncrementalHoareTripleChecker+Valid, 10 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.0s IncrementalHoareTripleChecker+Time [2025-03-04 02:58:48,767 INFO L436 NwaCegarLoop]: SdHoareTripleChecker [3 Valid, 337 Invalid, 10 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [0 Valid, 10 Invalid, 0 Unknown, 0 Unchecked, 0.0s Time] [2025-03-04 02:58:48,767 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 137 states. [2025-03-04 02:58:48,773 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 137 to 134. [2025-03-04 02:58:48,774 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 134 states, 85 states have (on average 1.2352941176470589) internal successors, (105), 87 states have internal predecessors, (105), 37 states have call successors, (37), 10 states have call predecessors, (37), 11 states have return successors, (40), 36 states have call predecessors, (40), 36 states have call successors, (40) [2025-03-04 02:58:48,775 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 134 states to 134 states and 182 transitions. [2025-03-04 02:58:48,775 INFO L78 Accepts]: Start accepts. Automaton has 134 states and 182 transitions. Word has length 123 [2025-03-04 02:58:48,775 INFO L84 Accepts]: Finished accepts. word is rejected. [2025-03-04 02:58:48,775 INFO L471 AbstractCegarLoop]: Abstraction has 134 states and 182 transitions. [2025-03-04 02:58:48,775 INFO L472 AbstractCegarLoop]: INTERPOLANT automaton has has 3 states, 3 states have (on average 19.0) internal successors, (57), 3 states have internal predecessors, (57), 2 states have call successors, (16), 2 states have call predecessors, (16), 2 states have return successors, (15), 2 states have call predecessors, (15), 2 states have call successors, (15) [2025-03-04 02:58:48,775 INFO L276 IsEmpty]: Start isEmpty. Operand 134 states and 182 transitions. [2025-03-04 02:58:48,776 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 132 [2025-03-04 02:58:48,776 INFO L210 NwaCegarLoop]: Found error trace [2025-03-04 02:58:48,777 INFO L218 NwaCegarLoop]: trace histogram [9, 9, 9, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2025-03-04 02:58:48,784 INFO L540 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (5)] Forceful destruction successful, exit code 0 [2025-03-04 02:58:48,977 WARN L453 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable3,5 /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2025-03-04 02:58:48,977 INFO L396 AbstractCegarLoop]: === Iteration 5 === Targeting __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2025-03-04 02:58:48,978 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2025-03-04 02:58:48,978 INFO L85 PathProgramCache]: Analyzing trace with hash 139685719, now seen corresponding path program 1 times [2025-03-04 02:58:48,978 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2025-03-04 02:58:48,978 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [480004685] [2025-03-04 02:58:48,978 INFO L97 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2025-03-04 02:58:48,978 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2025-03-04 02:58:48,996 INFO L108 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY partitioned 131 statements into 1 equivalence classes. [2025-03-04 02:58:49,012 INFO L111 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) and asserted 131 of 131 statements. [2025-03-04 02:58:49,012 INFO L114 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) [2025-03-04 02:58:49,012 INFO L115 AnnotateAndAsserter]: Conjunction of SSA is unsat [2025-03-04 02:58:49,257 INFO L134 CoverageAnalysis]: Checked inductivity of 194 backedges. 15 proven. 13 refuted. 0 times theorem prover too weak. 166 trivial. 0 not checked. [2025-03-04 02:58:49,257 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2025-03-04 02:58:49,257 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [480004685] [2025-03-04 02:58:49,257 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [480004685] provided 0 perfect and 1 imperfect interpolant sequences [2025-03-04 02:58:49,257 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1578541271] [2025-03-04 02:58:49,257 INFO L97 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2025-03-04 02:58:49,257 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2025-03-04 02:58:49,258 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2025-03-04 02:58:49,259 INFO L229 MonitoredProcess]: Starting monitored process 6 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2025-03-04 02:58:49,261 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (6)] Waiting until timeout for monitored process [2025-03-04 02:58:49,369 INFO L108 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY partitioned 131 statements into 1 equivalence classes. [2025-03-04 02:58:49,427 INFO L111 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) and asserted 131 of 131 statements. [2025-03-04 02:58:49,428 INFO L114 AnnotateAndAsserter]: Assert order NOT_INCREMENTALLY issued 1 check-sat command(s) [2025-03-04 02:58:49,428 INFO L115 AnnotateAndAsserter]: Conjunction of SSA is unsat [2025-03-04 02:58:49,430 INFO L256 TraceCheckSpWp]: Trace formula consists of 542 conjuncts, 68 conjuncts are in the unsatisfiable core [2025-03-04 02:58:49,437 INFO L279 TraceCheckSpWp]: Computing forward predicates... [2025-03-04 02:58:49,443 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 1, 1 stores, 0 select indices, 0 select index equivalence classes, 0 disjoint index pairs (out of 0 index pairs), introduced 0 new quantified variables, introduced 0 case distinctions, treesize of input 6 treesize of output 5 [2025-03-04 02:58:49,522 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 1 stores, 0 select indices, 0 select index equivalence classes, 1 disjoint index pairs (out of 0 index pairs), introduced 0 new quantified variables, introduced 0 case distinctions, treesize of input 24 treesize of output 9 [2025-03-04 02:58:49,528 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 1 stores, 0 select indices, 0 select index equivalence classes, 1 disjoint index pairs (out of 0 index pairs), introduced 0 new quantified variables, introduced 0 case distinctions, treesize of input 18 treesize of output 19 [2025-03-04 02:58:49,570 INFO L190 IndexEqualityManager]: detected not equals via solver [2025-03-04 02:58:49,571 INFO L190 IndexEqualityManager]: detected not equals via solver [2025-03-04 02:58:49,572 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 1 stores, 2 select indices, 2 select index equivalence classes, 3 disjoint index pairs (out of 1 index pairs), introduced 3 new quantified variables, introduced 0 case distinctions, treesize of input 35 treesize of output 40 [2025-03-04 02:58:49,576 INFO L190 IndexEqualityManager]: detected not equals via solver [2025-03-04 02:58:49,577 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 1 stores, 1 select indices, 1 select index equivalence classes, 1 disjoint index pairs (out of 0 index pairs), introduced 2 new quantified variables, introduced 0 case distinctions, treesize of input 26 treesize of output 28 [2025-03-04 02:58:49,605 INFO L349 Elim1Store]: treesize reduction 13, result has 40.9 percent of original size [2025-03-04 02:58:49,605 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 1 stores, 1 select indices, 1 select index equivalence classes, 0 disjoint index pairs (out of 0 index pairs), introduced 1 new quantified variables, introduced 1 case distinctions, treesize of input 25 treesize of output 22 [2025-03-04 02:58:49,616 INFO L190 IndexEqualityManager]: detected not equals via solver [2025-03-04 02:58:49,617 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 1, 0 stores, 2 select indices, 2 select index equivalence classes, 1 disjoint index pairs (out of 1 index pairs), introduced 2 new quantified variables, introduced 0 case distinctions, treesize of input 13 treesize of output 7 [2025-03-04 02:58:49,640 INFO L349 Elim1Store]: treesize reduction 13, result has 40.9 percent of original size [2025-03-04 02:58:49,641 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 1 stores, 1 select indices, 1 select index equivalence classes, 0 disjoint index pairs (out of 0 index pairs), introduced 1 new quantified variables, introduced 1 case distinctions, treesize of input 27 treesize of output 24 [2025-03-04 02:58:49,653 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 1, 0 stores, 2 select indices, 2 select index equivalence classes, 1 disjoint index pairs (out of 1 index pairs), introduced 2 new quantified variables, introduced 0 case distinctions, treesize of input 15 treesize of output 7 [2025-03-04 02:58:49,664 INFO L349 Elim1Store]: treesize reduction 4, result has 50.0 percent of original size [2025-03-04 02:58:49,665 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 1, 0 stores, 2 select indices, 2 select index equivalence classes, 0 disjoint index pairs (out of 1 index pairs), introduced 2 new quantified variables, introduced 1 case distinctions, treesize of input 11 treesize of output 11 [2025-03-04 02:58:49,723 INFO L349 Elim1Store]: treesize reduction 42, result has 20.8 percent of original size [2025-03-04 02:58:49,724 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 2 stores, 1 select indices, 1 select index equivalence classes, 0 disjoint index pairs (out of 0 index pairs), introduced 4 new quantified variables, introduced 2 case distinctions, treesize of input 115 treesize of output 119 [2025-03-04 02:58:49,729 INFO L190 IndexEqualityManager]: detected not equals via solver [2025-03-04 02:58:49,730 INFO L190 IndexEqualityManager]: detected not equals via solver [2025-03-04 02:58:49,735 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 1, 1 stores, 2 select indices, 2 select index equivalence classes, 3 disjoint index pairs (out of 1 index pairs), introduced 2 new quantified variables, introduced 0 case distinctions, treesize of input 99 treesize of output 90 [2025-03-04 02:58:49,739 INFO L190 IndexEqualityManager]: detected not equals via solver [2025-03-04 02:58:49,741 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 2, 1 stores, 1 select indices, 1 select index equivalence classes, 1 disjoint index pairs (out of 0 index pairs), introduced 1 new quantified variables, introduced 0 case distinctions, treesize of input 45 treesize of output 40 [2025-03-04 02:58:49,756 INFO L378 Elim1Store]: Elim1 eliminated variable of array dimension 1, 1 stores, 2 select indices, 2 select index equivalence classes, 3 disjoint index pairs (out of 1 index pairs), introduced 2 new quantified variables, introduced 0 case distinctions, treesize of input 31 treesize of output 25