java -ea -Xmx8000000000 -Xss4m -jar ./plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar -data @noDefault -ultimatedata ./data -tc ../../../trunk/examples/toolchains/AutomizerBplInline.xml -s ../../../trunk/examples/settings/ai/array-bench/reach_32bit_compound_exp_cong.epf -i ../../../trunk/examples/programs/toy/tooDifficultLoopInvariant/HierarchicalTraceAbstraction/SkatingStrawberry.bpl -------------------------------------------------------------------------------- This is Ultimate 0.1.24-a9d37a5-m [2019-02-28 13:08:30,715 INFO L170 SettingsManager]: Resetting all preferences to default values... [2019-02-28 13:08:30,717 INFO L174 SettingsManager]: Resetting UltimateCore preferences to default values [2019-02-28 13:08:30,732 INFO L177 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... [2019-02-28 13:08:30,733 INFO L174 SettingsManager]: Resetting Boogie Preprocessor preferences to default values [2019-02-28 13:08:30,734 INFO L174 SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values [2019-02-28 13:08:30,737 INFO L174 SettingsManager]: Resetting Abstract Interpretation preferences to default values [2019-02-28 13:08:30,739 INFO L174 SettingsManager]: Resetting LassoRanker preferences to default values [2019-02-28 13:08:30,741 INFO L174 SettingsManager]: Resetting Reaching Definitions preferences to default values [2019-02-28 13:08:30,742 INFO L174 SettingsManager]: Resetting SyntaxChecker preferences to default values [2019-02-28 13:08:30,743 INFO L177 SettingsManager]: Büchi Program Product provides no preferences, ignoring... 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[2019-02-28 13:08:30,784 INFO L98 SettingsManager]: Beginning loading settings from /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/settings/ai/array-bench/reach_32bit_compound_exp_cong.epf [2019-02-28 13:08:30,806 INFO L110 SettingsManager]: Loading preferences was successful [2019-02-28 13:08:30,807 INFO L112 SettingsManager]: Preferences different from defaults after loading the file: [2019-02-28 13:08:30,807 INFO L131 SettingsManager]: Preferences of Boogie Preprocessor differ from their defaults: [2019-02-28 13:08:30,808 INFO L133 SettingsManager]: * Show backtranslation warnings=false [2019-02-28 13:08:30,811 INFO L131 SettingsManager]: Preferences of Boogie Procedure Inliner differ from their defaults: [2019-02-28 13:08:30,811 INFO L133 SettingsManager]: * User list type=DISABLED [2019-02-28 13:08:30,811 INFO L133 SettingsManager]: * Inline calls to unimplemented procedures=true [2019-02-28 13:08:30,811 INFO L131 SettingsManager]: Preferences of Abstract Interpretation differ from their defaults: [2019-02-28 13:08:30,812 INFO L133 SettingsManager]: * Explicit value domain=true [2019-02-28 13:08:30,812 INFO L133 SettingsManager]: * Abstract domain for RCFG-of-the-future=PoormanAbstractDomain [2019-02-28 13:08:30,812 INFO L133 SettingsManager]: * Octagon Domain=false [2019-02-28 13:08:30,812 INFO L133 SettingsManager]: * Abstract domain=CompoundDomain [2019-02-28 13:08:30,812 INFO L133 SettingsManager]: * Check feasibility of abstract posts with an SMT solver=true [2019-02-28 13:08:30,812 INFO L133 SettingsManager]: * Interval Domain=false [2019-02-28 13:08:30,813 INFO L131 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2019-02-28 13:08:30,814 INFO L133 SettingsManager]: * Create parallel compositions if possible=false [2019-02-28 13:08:30,817 INFO L133 SettingsManager]: * Use SBE=true [2019-02-28 13:08:30,817 INFO L131 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2019-02-28 13:08:30,817 INFO L133 SettingsManager]: * sizeof long=4 [2019-02-28 13:08:30,818 INFO L133 SettingsManager]: * Overapproximate operations on floating types=true [2019-02-28 13:08:30,818 INFO L133 SettingsManager]: * sizeof POINTER=4 [2019-02-28 13:08:30,818 INFO L133 SettingsManager]: * Check division by zero=IGNORE [2019-02-28 13:08:30,818 INFO L133 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2019-02-28 13:08:30,818 INFO L133 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2019-02-28 13:08:30,819 INFO L133 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2019-02-28 13:08:30,819 INFO L133 SettingsManager]: * sizeof long double=12 [2019-02-28 13:08:30,819 INFO L133 SettingsManager]: * Check if freed pointer was valid=false [2019-02-28 13:08:30,819 INFO L133 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2019-02-28 13:08:30,819 INFO L131 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2019-02-28 13:08:30,819 INFO L133 SettingsManager]: * Size of a code block=SequenceOfStatements [2019-02-28 13:08:30,820 INFO L133 SettingsManager]: * SMT solver=External_DefaultMode [2019-02-28 13:08:30,823 INFO L133 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:16092 -smt2 -in -t:200000 [2019-02-28 13:08:30,823 INFO L131 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2019-02-28 13:08:30,823 INFO L133 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2019-02-28 13:08:30,823 INFO L133 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles [2019-02-28 13:08:30,823 INFO L133 SettingsManager]: * Trace refinement strategy=TAIPAN [2019-02-28 13:08:30,824 INFO L133 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2019-02-28 13:08:30,824 INFO L133 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:16092 -smt2 -in [2019-02-28 13:08:30,824 INFO L133 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2019-02-28 13:08:30,824 INFO L133 SettingsManager]: * Abstract interpretation Mode=USE_PREDICATES [2019-02-28 13:08:30,864 INFO L81 nceAwareModelManager]: Repository-Root is: /tmp [2019-02-28 13:08:30,876 INFO L258 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2019-02-28 13:08:30,880 INFO L214 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2019-02-28 13:08:30,881 INFO L271 PluginConnector]: Initializing Boogie PL CUP Parser... [2019-02-28 13:08:30,882 INFO L276 PluginConnector]: Boogie PL CUP Parser initialized [2019-02-28 13:08:30,883 INFO L418 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/programs/toy/tooDifficultLoopInvariant/HierarchicalTraceAbstraction/SkatingStrawberry.bpl [2019-02-28 13:08:30,883 INFO L111 BoogieParser]: Parsing: '/storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/programs/toy/tooDifficultLoopInvariant/HierarchicalTraceAbstraction/SkatingStrawberry.bpl' [2019-02-28 13:08:30,915 INFO L296 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2019-02-28 13:08:30,916 INFO L131 ToolchainWalker]: Walking toolchain with 4 elements. [2019-02-28 13:08:30,917 INFO L113 PluginConnector]: ------------------------Boogie Procedure Inliner---------------------------- [2019-02-28 13:08:30,917 INFO L271 PluginConnector]: Initializing Boogie Procedure Inliner... [2019-02-28 13:08:30,917 INFO L276 PluginConnector]: Boogie Procedure Inliner initialized [2019-02-28 13:08:30,933 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Procedure Inliner for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/1) ... [2019-02-28 13:08:30,942 INFO L185 PluginConnector]: Executing the observer Inliner from plugin Boogie Procedure Inliner for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/1) ... [2019-02-28 13:08:30,950 WARN L165 Inliner]: Program contained no entry procedure! [2019-02-28 13:08:30,950 WARN L168 Inliner]: Missing entry procedures: [ULTIMATE.start] [2019-02-28 13:08:30,950 WARN L175 Inliner]: Fallback enabled. All procedures will be processed. [2019-02-28 13:08:30,952 INFO L132 PluginConnector]: ------------------------ END Boogie Procedure Inliner---------------------------- [2019-02-28 13:08:30,952 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2019-02-28 13:08:30,953 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2019-02-28 13:08:30,953 INFO L276 PluginConnector]: Boogie Preprocessor initialized [2019-02-28 13:08:30,963 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/1) ... [2019-02-28 13:08:30,963 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/1) ... [2019-02-28 13:08:30,964 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/1) ... [2019-02-28 13:08:30,964 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/1) ... [2019-02-28 13:08:30,967 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/1) ... [2019-02-28 13:08:30,971 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/1) ... [2019-02-28 13:08:30,971 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/1) ... [2019-02-28 13:08:30,973 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2019-02-28 13:08:30,973 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2019-02-28 13:08:30,974 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2019-02-28 13:08:30,974 INFO L276 PluginConnector]: RCFGBuilder initialized [2019-02-28 13:08:30,975 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/1) ... No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 Starting monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:16092 -smt2 -in -t:200000 (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:16092 -smt2 -in -t:200000 [2019-02-28 13:08:31,037 INFO L124 BoogieDeclarations]: Specification and implementation of procedure main given in one single declaration [2019-02-28 13:08:31,037 INFO L130 BoogieDeclarations]: Found specification of procedure main [2019-02-28 13:08:31,037 INFO L138 BoogieDeclarations]: Found implementation of procedure main [2019-02-28 13:08:31,362 INFO L278 CfgBuilder]: Using library mode [2019-02-28 13:08:31,362 INFO L286 CfgBuilder]: Removed 1 assue(true) statements. [2019-02-28 13:08:31,364 INFO L202 PluginConnector]: Adding new model SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 28.02 01:08:31 BoogieIcfgContainer [2019-02-28 13:08:31,364 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2019-02-28 13:08:31,365 INFO L113 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2019-02-28 13:08:31,365 INFO L271 PluginConnector]: Initializing TraceAbstraction... [2019-02-28 13:08:31,368 INFO L276 PluginConnector]: TraceAbstraction initialized [2019-02-28 13:08:31,368 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 28.02 01:08:30" (1/2) ... [2019-02-28 13:08:31,369 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@3a083017 and model type SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 28.02 01:08:31, skipping insertion in model container [2019-02-28 13:08:31,369 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "SkatingStrawberry.bpl de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 28.02 01:08:31" (2/2) ... [2019-02-28 13:08:31,371 INFO L112 eAbstractionObserver]: Analyzing ICFG SkatingStrawberry.bpl [2019-02-28 13:08:31,379 INFO L156 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:FPandBP Determinization: PREDICATE_ABSTRACTION [2019-02-28 13:08:31,386 INFO L168 ceAbstractionStarter]: Appying trace abstraction to program that has 1 error locations. [2019-02-28 13:08:31,401 INFO L257 AbstractCegarLoop]: Starting to check reachability of 1 error locations. [2019-02-28 13:08:31,431 INFO L382 AbstractCegarLoop]: Interprodecural is true [2019-02-28 13:08:31,431 INFO L383 AbstractCegarLoop]: Hoare is true [2019-02-28 13:08:31,431 INFO L384 AbstractCegarLoop]: Compute interpolants for FPandBP [2019-02-28 13:08:31,432 INFO L385 AbstractCegarLoop]: Backedges is STRAIGHT_LINE [2019-02-28 13:08:31,432 INFO L386 AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION [2019-02-28 13:08:31,432 INFO L387 AbstractCegarLoop]: Difference is false [2019-02-28 13:08:31,432 INFO L388 AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA [2019-02-28 13:08:31,432 INFO L393 AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce======== [2019-02-28 13:08:31,446 INFO L276 IsEmpty]: Start isEmpty. Operand 6 states. [2019-02-28 13:08:31,451 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 4 [2019-02-28 13:08:31,451 INFO L394 BasicCegarLoop]: Found error trace [2019-02-28 13:08:31,452 INFO L402 BasicCegarLoop]: trace histogram [1, 1, 1] [2019-02-28 13:08:31,455 INFO L423 AbstractCegarLoop]: === Iteration 1 === [mainErr0ASSERT_VIOLATIONASSERT]=== [2019-02-28 13:08:31,459 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2019-02-28 13:08:31,459 INFO L82 PathProgramCache]: Analyzing trace with hash 30048, now seen corresponding path program 1 times [2019-02-28 13:08:31,461 INFO L69 tionRefinementEngine]: Using refinement strategy TaipanRefinementStrategy [2019-02-28 13:08:31,502 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2019-02-28 13:08:31,503 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2019-02-28 13:08:31,503 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2019-02-28 13:08:31,503 INFO L289 anRefinementStrategy]: Using traceCheck mode SMTINTERPOL with AssertCodeBlockOrder NOT_INCREMENTALLY (IT: Craig_TreeInterpolation) [2019-02-28 13:08:31,539 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2019-02-28 13:08:31,943 INFO L273 TraceCheckUtils]: 0: Hoare triple {9#true} y := x + 1;a := a[x := 1000];a := a[y := 0]; {11#(and (= 1000 (select main_a main_x)) (= (select main_a main_y) 0))} is VALID [2019-02-28 13:08:31,948 INFO L273 TraceCheckUtils]: 1: Hoare triple {11#(and (= 1000 (select main_a main_x)) (= (select main_a main_y) 0))} assume a[x] == 0; {12#(= (select main_a main_y) 1000)} is VALID [2019-02-28 13:08:31,949 INFO L273 TraceCheckUtils]: 2: Hoare triple {12#(= (select main_a main_y) 1000)} assume !(a[y] == 1000); {10#false} is VALID [2019-02-28 13:08:31,950 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2019-02-28 13:08:31,952 INFO L312 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2019-02-28 13:08:31,952 INFO L327 seRefinementStrategy]: Number of different interpolants: perfect sequences [2] imperfect sequences [] total 2 [2019-02-28 13:08:31,952 INFO L257 anRefinementStrategy]: Using the first perfect interpolant sequence [2019-02-28 13:08:31,958 INFO L78 Accepts]: Start accepts. Automaton has 4 states. Word has length 3 [2019-02-28 13:08:31,959 INFO L84 Accepts]: Finished accepts. word is accepted. [2019-02-28 13:08:31,962 INFO L86 InductivityCheck]: Starting indutivity check of a Floyd-Hoare automaton with 4 states. [2019-02-28 13:08:31,985 INFO L119 InductivityCheck]: Floyd-Hoare automaton has 3 edges. 3 inductive. 0 not inductive. 0 times theorem prover too weak to decide inductivity. [2019-02-28 13:08:31,985 INFO L459 AbstractCegarLoop]: Interpolant automaton has 4 states [2019-02-28 13:08:31,992 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2019-02-28 13:08:31,993 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2019-02-28 13:08:31,995 INFO L87 Difference]: Start difference. First operand 6 states. Second operand 4 states. [2019-02-28 13:08:32,221 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2019-02-28 13:08:32,221 INFO L93 Difference]: Finished difference Result 15 states and 15 transitions. [2019-02-28 13:08:32,222 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 4 states. [2019-02-28 13:08:32,222 INFO L78 Accepts]: Start accepts. Automaton has 4 states. Word has length 3 [2019-02-28 13:08:32,222 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2019-02-28 13:08:32,224 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 4 states. [2019-02-28 13:08:32,229 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 4 states to 4 states and 15 transitions. [2019-02-28 13:08:32,230 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 4 states. [2019-02-28 13:08:32,232 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 4 states to 4 states and 15 transitions. [2019-02-28 13:08:32,232 INFO L86 InductivityCheck]: Starting indutivity check of a Floyd-Hoare automaton with 4 states and 15 transitions. [2019-02-28 13:08:32,398 INFO L119 InductivityCheck]: Floyd-Hoare automaton has 15 edges. 15 inductive. 0 not inductive. 0 times theorem prover too weak to decide inductivity. [2019-02-28 13:08:32,407 INFO L225 Difference]: With dead ends: 15 [2019-02-28 13:08:32,407 INFO L226 Difference]: Without dead ends: 5 [2019-02-28 13:08:32,420 INFO L631 BasicCegarLoop]: 0 DeclaredPredicates, 2 GetRequests, 0 SyntacticMatches, 0 SemanticMatches, 2 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.2s TimeCoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2019-02-28 13:08:32,437 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 5 states. [2019-02-28 13:08:32,455 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 5 to 5. [2019-02-28 13:08:32,455 INFO L214 AbstractMinimizeNwa]: Start testing correctness of minimizeSevpa [2019-02-28 13:08:32,456 INFO L82 GeneralOperation]: Start isEquivalent. First operand 5 states. Second operand 5 states. [2019-02-28 13:08:32,456 INFO L74 IsIncluded]: Start isIncluded. First operand 5 states. Second operand 5 states. [2019-02-28 13:08:32,456 INFO L87 Difference]: Start difference. First operand 5 states. Second operand 5 states. [2019-02-28 13:08:32,457 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2019-02-28 13:08:32,457 INFO L93 Difference]: Finished difference Result 5 states and 5 transitions. [2019-02-28 13:08:32,458 INFO L276 IsEmpty]: Start isEmpty. Operand 5 states and 5 transitions. [2019-02-28 13:08:32,458 INFO L282 IsEmpty]: Finished isEmpty. No accepting run. [2019-02-28 13:08:32,458 INFO L83 IsIncluded]: Finished isIncluded. Language is included [2019-02-28 13:08:32,458 INFO L74 IsIncluded]: Start isIncluded. First operand 5 states. Second operand 5 states. [2019-02-28 13:08:32,459 INFO L87 Difference]: Start difference. First operand 5 states. Second operand 5 states. [2019-02-28 13:08:32,460 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2019-02-28 13:08:32,460 INFO L93 Difference]: Finished difference Result 5 states and 5 transitions. [2019-02-28 13:08:32,460 INFO L276 IsEmpty]: Start isEmpty. Operand 5 states and 5 transitions. [2019-02-28 13:08:32,460 INFO L282 IsEmpty]: Finished isEmpty. No accepting run. [2019-02-28 13:08:32,461 INFO L83 IsIncluded]: Finished isIncluded. Language is included [2019-02-28 13:08:32,461 INFO L88 GeneralOperation]: Finished isEquivalent. [2019-02-28 13:08:32,461 INFO L221 AbstractMinimizeNwa]: Finished testing correctness of minimizeSevpa [2019-02-28 13:08:32,461 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 5 states. [2019-02-28 13:08:32,462 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 5 states to 5 states and 5 transitions. [2019-02-28 13:08:32,464 INFO L78 Accepts]: Start accepts. Automaton has 5 states and 5 transitions. Word has length 3 [2019-02-28 13:08:32,464 INFO L84 Accepts]: Finished accepts. word is rejected. [2019-02-28 13:08:32,464 INFO L480 AbstractCegarLoop]: Abstraction has 5 states and 5 transitions. [2019-02-28 13:08:32,464 INFO L481 AbstractCegarLoop]: Interpolant automaton has 4 states. [2019-02-28 13:08:32,465 INFO L276 IsEmpty]: Start isEmpty. Operand 5 states and 5 transitions. [2019-02-28 13:08:32,465 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 5 [2019-02-28 13:08:32,465 INFO L394 BasicCegarLoop]: Found error trace [2019-02-28 13:08:32,465 INFO L402 BasicCegarLoop]: trace histogram [1, 1, 1, 1] [2019-02-28 13:08:32,466 INFO L423 AbstractCegarLoop]: === Iteration 2 === [mainErr0ASSERT_VIOLATIONASSERT]=== [2019-02-28 13:08:32,466 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2019-02-28 13:08:32,466 INFO L82 PathProgramCache]: Analyzing trace with hash 927622, now seen corresponding path program 1 times [2019-02-28 13:08:32,466 INFO L69 tionRefinementEngine]: Using refinement strategy TaipanRefinementStrategy [2019-02-28 13:08:32,467 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2019-02-28 13:08:32,467 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2019-02-28 13:08:32,467 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2019-02-28 13:08:32,468 INFO L289 anRefinementStrategy]: Using traceCheck mode SMTINTERPOL with AssertCodeBlockOrder NOT_INCREMENTALLY (IT: Craig_TreeInterpolation) [2019-02-28 13:08:32,512 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2019-02-28 13:08:32,774 WARN L181 SmtUtils]: Spent 179.00 ms on a formula simplification. DAG size of input: 25 DAG size of output: 18 [2019-02-28 13:08:32,819 INFO L273 TraceCheckUtils]: 0: Hoare triple {49#true} y := x + 1;a := a[x := 1000];a := a[y := 0]; {51#(and (<= (+ main_x 1) main_y) (= (select main_a main_x) 1000) (or (< (div (+ main_y 1) 256) (+ (div (+ main_x 1) 256) 1)) (<= main_y (+ main_x 1))))} is VALID [2019-02-28 13:08:32,821 INFO L273 TraceCheckUtils]: 1: Hoare triple {51#(and (<= (+ main_x 1) main_y) (= (select main_a main_x) 1000) (or (< (div (+ main_y 1) 256) (+ (div (+ main_x 1) 256) 1)) (<= main_y (+ main_x 1))))} xold := x;yold := y;x := (x + 1) % 256;y := (y + 1) % 256;a := a[x := a[xold]];a := a[y := a[yold]]; {52#(= (select main_a main_x) 1000)} is VALID [2019-02-28 13:08:32,822 INFO L273 TraceCheckUtils]: 2: Hoare triple {52#(= (select main_a main_x) 1000)} assume a[x] == 0; {50#false} is VALID [2019-02-28 13:08:32,822 INFO L273 TraceCheckUtils]: 3: Hoare triple {50#false} assume !(a[y] == 1000); {50#false} is VALID [2019-02-28 13:08:32,823 INFO L134 CoverageAnalysis]: Checked inductivity of 1 backedges. 0 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2019-02-28 13:08:32,823 INFO L300 seRefinementStrategy]: The current sequences of interpolants are not accepted, trying to find more. [2019-02-28 13:08:32,823 INFO L193 anRefinementStrategy]: Switched to InterpolantGenerator mode ABSTRACT_INTERPRETATION [2019-02-28 13:08:32,824 INFO L205 CegarAbsIntRunner]: Running AI on error trace of length 5 with the following transitions: [2019-02-28 13:08:32,826 INFO L207 CegarAbsIntRunner]: [0], [4], [8], [9] [2019-02-28 13:08:32,864 INFO L148 AbstractInterpreter]: Using domain CompoundDomain [CongruenceDomain, ExplicitValueDomain] [2019-02-28 13:08:32,864 INFO L101 FixpointEngine]: Starting fixpoint engine with domain CompoundDomain (maxUnwinding=3, maxParallelStates=2) [2019-02-28 13:08:33,001 INFO L263 AbstractInterpreter]: Some error location(s) were reachable [2019-02-28 13:08:33,003 INFO L272 AbstractInterpreter]: Visited 4 different actions 4 times. Never merged. Never widened. Performed 22 root evaluator evaluations with a maximum evaluation depth of 3. Performed 22 inverse root evaluator evaluations with a maximum inverse evaluation depth of 3. Found 1 fixpoints after 1 different actions. Largest state had 0 variables. [2019-02-28 13:08:33,007 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2019-02-28 13:08:33,009 INFO L422 seRefinementStrategy]: Interpolation failed due to KNOWN_IGNORE: Unknown [2019-02-28 13:08:33,010 INFO L300 seRefinementStrategy]: The current sequences of interpolants are not accepted, trying to find more. [2019-02-28 13:08:33,010 INFO L193 anRefinementStrategy]: Switched to InterpolantGenerator mode Z3_IG No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 Starting monitored process 2 with z3 -smt2 -in SMTLIB2_COMPLIANT=true -t:12000 (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 2 with z3 -smt2 -in SMTLIB2_COMPLIANT=true -t:12000 [2019-02-28 13:08:33,030 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2019-02-28 13:08:33,030 INFO L289 anRefinementStrategy]: Using traceCheck mode Z3_IG with AssertCodeBlockOrder NOT_INCREMENTALLY (IT: FPandBP) [2019-02-28 13:08:33,059 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2019-02-28 13:08:33,062 WARN L254 TraceCheckSpWp]: Trace formula consists of 17 conjuncts, 12 conjunts are in the unsatisfiable core [2019-02-28 13:08:33,085 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2019-02-28 13:08:33,090 INFO L279 TraceCheckSpWp]: Computing forward predicates... [2019-02-28 13:08:33,288 INFO L442 Elim1Store]: Elim1 did not use preprocessing 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 1 new quantified variables, introduced 0 case distinctions, treesize of input 9 treesize of output 12 [2019-02-28 13:08:33,342 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:33,344 INFO L442 Elim1Store]: Elim1 did not use preprocessing eliminated variable of array dimension 1, 1 stores, 1 select indices, 1 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 12 treesize of output 11 [2019-02-28 13:08:33,351 INFO L315 ElimStorePlain]: Start of recursive call 3: End of recursive call: and 1 xjuncts. [2019-02-28 13:08:33,365 INFO L315 ElimStorePlain]: Start of recursive call 2: 1 dim-1 vars, End of recursive call: and 1 xjuncts. [2019-02-28 13:08:33,372 INFO L315 ElimStorePlain]: Start of recursive call 1: 1 dim-1 vars, End of recursive call: and 1 xjuncts. [2019-02-28 13:08:33,374 INFO L209 ElimStorePlain]: Needed 3 recursive calls to eliminate 1 variables, input treesize:15, output treesize:16 [2019-02-28 13:08:33,378 WARN L397 uantifierElimination]: Trying to double check SDD result, but SMT solver's response was UNKNOWN. [2019-02-28 13:08:33,379 WARN L398 uantifierElimination]: Input elimination task: ∃ [v_main_a_11]. (and (= main_a (store (store v_main_a_11 main_x 1000) main_y 0)) (= main_y (+ main_x 1))) [2019-02-28 13:08:33,379 WARN L399 uantifierElimination]: ElimStorePlain result: ∃ []. (and (= (select main_a main_x) 1000) (= (select main_a main_y) 0) (= main_y (+ main_x 1))) [2019-02-28 13:08:33,656 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:33,664 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:33,692 INFO L442 Elim1Store]: Elim1 did not use preprocessing eliminated variable of array dimension 1, 1 stores, 3 select indices, 3 select index equivalence classes, 3 disjoint index pairs (out of 3 index pairs), introduced 2 new quantified variables, introduced 4 case distinctions, treesize of input 34 treesize of output 45 [2019-02-28 13:08:33,730 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:33,735 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:33,737 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:33,744 INFO L442 Elim1Store]: Elim1 did not use preprocessing eliminated variable of array dimension 1, 1 stores, 3 select indices, 3 select index equivalence classes, 4 disjoint index pairs (out of 3 index pairs), introduced 1 new quantified variables, introduced 1 case distinctions, treesize of input 34 treesize of output 36 [2019-02-28 13:08:33,753 INFO L315 ElimStorePlain]: Start of recursive call 4: End of recursive call: and 1 xjuncts. [2019-02-28 13:08:34,045 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,095 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,118 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,164 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,179 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,182 INFO L289 Elim1Store]: Index analysis took 160 ms [2019-02-28 13:08:34,196 INFO L442 Elim1Store]: Elim1 did not use preprocessing eliminated variable of array dimension 1, 1 stores, 4 select indices, 4 select index equivalence classes, 6 disjoint index pairs (out of 6 index pairs), introduced 1 new quantified variables, introduced 3 case distinctions, treesize of input 32 treesize of output 34 [2019-02-28 13:08:34,207 INFO L315 ElimStorePlain]: Start of recursive call 5: End of recursive call: and 1 xjuncts. [2019-02-28 13:08:34,258 INFO L315 ElimStorePlain]: Start of recursive call 3: 2 dim-1 vars, End of recursive call: and 2 xjuncts. [2019-02-28 13:08:34,338 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,339 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,353 INFO L442 Elim1Store]: Elim1 did not use preprocessing eliminated variable of array dimension 1, 1 stores, 2 select indices, 2 select index equivalence classes, 2 disjoint index pairs (out of 1 index pairs), introduced 2 new quantified variables, introduced 2 case distinctions, treesize of input 33 treesize of output 44 [2019-02-28 13:08:34,368 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,374 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,375 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,378 INFO L442 Elim1Store]: Elim1 did not use preprocessing 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 0 new quantified variables, introduced 0 case distinctions, treesize of input 33 treesize of output 32 [2019-02-28 13:08:34,380 INFO L315 ElimStorePlain]: Start of recursive call 7: End of recursive call: and 1 xjuncts. [2019-02-28 13:08:34,437 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,439 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,440 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,448 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,449 INFO L187 IndexEqualityManager]: detected not equals via solver [2019-02-28 13:08:34,456 INFO L442 Elim1Store]: Elim1 did not use preprocessing eliminated variable of array dimension 1, 1 stores, 3 select indices, 3 select index equivalence classes, 5 disjoint index pairs (out of 3 index pairs), introduced 0 new quantified variables, introduced 1 case distinctions, treesize of input 32 treesize of output 31 [2019-02-28 13:08:34,459 INFO L315 ElimStorePlain]: Start of recursive call 8: End of recursive call: and 1 xjuncts. [2019-02-28 13:08:34,567 INFO L315 ElimStorePlain]: Start of recursive call 6: 2 dim-1 vars, End of recursive call: and 2 xjuncts. [2019-02-28 13:08:34,689 INFO L315 ElimStorePlain]: Start of recursive call 2: 2 dim-1 vars, End of recursive call: and 3 xjuncts. [2019-02-28 13:08:34,738 INFO L315 ElimStorePlain]: Start of recursive call 1: 2 dim-0 vars, 1 dim-1 vars, End of recursive call: 3 dim-0 vars, and 2 xjuncts. [2019-02-28 13:08:34,738 INFO L209 ElimStorePlain]: Needed 8 recursive calls to eliminate 3 variables, input treesize:42, output treesize:72 [2019-02-28 13:11:58,038 WARN L397 uantifierElimination]: Trying to double check SDD result, but SMT solver's response was UNKNOWN. [2019-02-28 13:11:58,038 WARN L398 uantifierElimination]: Input elimination task: ∃ [v_main_a_12, main_xold, main_yold]. (let ((.cse0 (+ main_xold 1)) (.cse2 (select v_main_a_12 main_xold))) (and (= (select v_main_a_12 .cse0) 0) (= main_x (mod .cse0 256)) (= (let ((.cse1 (store v_main_a_12 main_x .cse2))) (store .cse1 (mod (+ main_xold 2) 256) (select .cse1 main_yold))) main_a) (= .cse2 1000))) [2019-02-28 13:11:58,038 WARN L399 uantifierElimination]: ElimStorePlain result: ∃ [main_xold, main_yold, v_prenex_4]. (let ((.cse1 (select main_a main_x))) (or (let ((.cse0 (select main_a (+ main_x (- 1))))) (and (= main_x (mod main_x 256)) (= 1000 .cse0) (= (select main_a (mod (+ main_x 1) 256)) (select main_a v_prenex_4)) (= .cse1 .cse0))) (let ((.cse2 (select main_a main_xold)) (.cse3 (+ main_xold 1))) (and (= (select main_a (mod (+ main_xold 2) 256)) (select main_a main_yold)) (= .cse1 .cse2) (= 0 (select main_a .cse3)) (= .cse2 1000) (= main_x (mod .cse3 256)))))) [2019-02-28 13:11:59,645 INFO L273 TraceCheckUtils]: 0: Hoare triple {49#true} y := x + 1;a := a[x := 1000];a := a[y := 0]; {56#(and (= (select main_a main_x) 1000) (= (select main_a main_y) 0) (= main_y (+ main_x 1)))} is VALID [2019-02-28 13:15:19,764 INFO L273 TraceCheckUtils]: 1: Hoare triple {56#(and (= (select main_a main_x) 1000) (= (select main_a main_y) 0) (= main_y (+ main_x 1)))} xold := x;yold := y;x := (x + 1) % 256;y := (y + 1) % 256;a := a[x := a[xold]];a := a[y := a[yold]]; {60#(or (exists ((main_xold Int) (main_yold Int)) (and (= (select main_a (mod (+ main_xold 2) 256)) (select main_a main_yold)) (= (select main_a main_x) (select main_a main_xold)) (= 0 (select main_a (+ main_xold 1))) (= (select main_a main_xold) 1000) (= main_x (mod (+ main_xold 1) 256)))) (and (= main_x (mod main_x 256)) (= 1000 (select main_a (+ main_x (- 1)))) (= (select main_a main_x) (select main_a (+ main_x (- 1))))))} is UNKNOWN [2019-02-28 13:15:19,895 INFO L273 TraceCheckUtils]: 2: Hoare triple {60#(or (exists ((main_xold Int) (main_yold Int)) (and (= (select main_a (mod (+ main_xold 2) 256)) (select main_a main_yold)) (= (select main_a main_x) (select main_a main_xold)) (= 0 (select main_a (+ main_xold 1))) (= (select main_a main_xold) 1000) (= main_x (mod (+ main_xold 1) 256)))) (and (= main_x (mod main_x 256)) (= 1000 (select main_a (+ main_x (- 1)))) (= (select main_a main_x) (select main_a (+ main_x (- 1))))))} assume a[x] == 0; {50#false} is VALID [2019-02-28 13:15:19,896 INFO L273 TraceCheckUtils]: 3: Hoare triple {50#false} assume !(a[y] == 1000); {50#false} is VALID [2019-02-28 13:15:19,896 INFO L134 CoverageAnalysis]: Checked inductivity of 1 backedges. 0 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2019-02-28 13:15:19,897 INFO L322 TraceCheckSpWp]: Computing backward predicates... [2019-02-28 13:15:20,043 INFO L273 TraceCheckUtils]: 3: Hoare triple {50#false} assume !(a[y] == 1000); {50#false} is VALID [2019-02-28 13:15:20,048 INFO L273 TraceCheckUtils]: 2: Hoare triple {70#(not (= (select main_a main_x) 0))} assume a[x] == 0; {50#false} is VALID [2019-02-28 13:15:20,051 INFO L273 TraceCheckUtils]: 1: Hoare triple {74#(forall ((v_main_yold_2 Int)) (not (= 0 (select (store (store main_a (mod (+ main_x 1) 256) (select main_a main_x)) (mod (+ main_y 1) 256) (select (store main_a (mod (+ main_x 1) 256) (select main_a main_x)) v_main_yold_2)) (mod (+ main_x 1) 256)))))} xold := x;yold := y;x := (x + 1) % 256;y := (y + 1) % 256;a := a[x := a[xold]];a := a[y := a[yold]]; {70#(not (= (select main_a main_x) 0))} is VALID [2019-02-28 13:15:20,054 INFO L273 TraceCheckUtils]: 0: Hoare triple {49#true} y := x + 1;a := a[x := 1000];a := a[y := 0]; {74#(forall ((v_main_yold_2 Int)) (not (= 0 (select (store (store main_a (mod (+ main_x 1) 256) (select main_a main_x)) (mod (+ main_y 1) 256) (select (store main_a (mod (+ main_x 1) 256) (select main_a main_x)) v_main_yold_2)) (mod (+ main_x 1) 256)))))} is VALID [2019-02-28 13:15:20,055 INFO L134 CoverageAnalysis]: Checked inductivity of 1 backedges. 0 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2019-02-28 13:15:20,079 INFO L312 seRefinementStrategy]: Constructing automaton from 0 perfect and 3 imperfect interpolant sequences. [2019-02-28 13:15:20,079 INFO L327 seRefinementStrategy]: Number of different interpolants: perfect sequences [] imperfect sequences [3, 3, 3] total 7 [2019-02-28 13:15:20,079 INFO L250 anRefinementStrategy]: Using the first two imperfect interpolant sequences [2019-02-28 13:15:20,080 INFO L78 Accepts]: Start accepts. Automaton has 6 states. Word has length 4 [2019-02-28 13:15:20,081 INFO L84 Accepts]: Finished accepts. word is accepted. [2019-02-28 13:15:20,081 INFO L86 InductivityCheck]: Starting indutivity check of a Floyd-Hoare automaton with 6 states. [2019-02-28 13:18:40,313 INFO L119 InductivityCheck]: Floyd-Hoare automaton has 7 edges. 6 inductive. 0 not inductive. 1 times theorem prover too weak to decide inductivity. [2019-02-28 13:18:40,314 INFO L459 AbstractCegarLoop]: Interpolant automaton has 6 states [2019-02-28 13:18:40,314 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 6 interpolants. [2019-02-28 13:18:40,314 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=24, Invalid=32, Unknown=0, NotChecked=0, Total=56 [2019-02-28 13:18:40,314 INFO L87 Difference]: Start difference. First operand 5 states and 5 transitions. Second operand 6 states.