(0) Obligation:

JBC Problem based on JBC Program:
/**
* Example taken from "A Term Rewriting Approach to the Automated Termination
* Analysis of Imperative Programs" (http://www.cs.unm.edu/~spf/papers/2009-02.pdf)
* and converted to Java.
*/

public class PastaA9 {
public static void main(String[] args) {
Random.args = args;
int x = Random.random();
int y = Random.random();
int z = Random.random();

if (y > 0) {
while (x >= z) {
z += y;
}
}
}
}


public class Random {
static String[] args;
static int index = 0;

public static int random() {
String string = args[index];
index++;
return string.length();
}
}


(1) JBCToGraph (SOUND transformation)

Constructed TerminationGraph.

(2) Obligation:

Termination Graph based on JBC Program:
PastaA9.main([Ljava/lang/String;)V: Graph of 249 nodes with 1 SCC.


(3) TerminationGraphToSCCProof (SOUND transformation)

Splitted TerminationGraph to 1 SCCs.

(4) Obligation:

SCC of termination graph based on JBC Program.
SCC contains nodes from the following methods: PastaA9.main([Ljava/lang/String;)V
SCC calls the following helper methods:
Performed SCC analyses:
  • Used field analysis yielded the following read fields:
  • Marker field analysis yielded the following relations that could be markers:

(5) SCCToIntTRSProof (SOUND transformation)

Transformed FIGraph SCCs to intTRSs. Log:

Generated rules. Obtained 10 IRules

P rules:
f676_0_main_Load(EOS, i18, i97, i88, i18) → f686_0_main_LT(EOS, i18, i97, i88, i18, i88)
f686_0_main_LT(EOS, i18, i97, i88, i18, i88) → f704_0_main_LT(EOS, i18, i97, i88, i18, i88)
f704_0_main_LT(EOS, i18, i97, i88, i18, i88) → f733_0_main_Load(EOS, i18, i97, i88) | >=(i18, i88)
f733_0_main_Load(EOS, i18, i97, i88) → f751_0_main_Load(EOS, i18, i97, i88)
f751_0_main_Load(EOS, i18, i97, i88) → f764_0_main_IntArithmetic(EOS, i18, i97, i88, i97)
f764_0_main_IntArithmetic(EOS, i18, i97, i88, i97) → f783_0_main_Store(EOS, i18, i97, +(i88, i97)) | &&(>=(i88, 0), >(i97, 0))
f783_0_main_Store(EOS, i18, i97, i108) → f797_0_main_JMP(EOS, i18, i97, i108)
f797_0_main_JMP(EOS, i18, i97, i108) → f834_0_main_Load(EOS, i18, i97, i108)
f834_0_main_Load(EOS, i18, i97, i108) → f663_0_main_Load(EOS, i18, i97, i108)
f663_0_main_Load(EOS, i18, i97, i88) → f676_0_main_Load(EOS, i18, i97, i88, i18)

Combined rules. Obtained 1 IRules

P rules:
f676_0_main_Load(EOS, x0, x1, x2, x0) → f676_0_main_Load(EOS, x0, x1, +(x2, x1), x0) | &&(&&(>(+(x2, 1), 0), >(x1, 0)), <=(x2, x0))

Filtered ground terms:


f676_0_main_Load(x1, x2, x3, x4, x5) → f676_0_main_Load(x2, x3, x4, x5)
Cond_f676_0_main_Load(x1, x2, x3, x4, x5, x6) → Cond_f676_0_main_Load(x1, x3, x4, x5, x6)

Filtered duplicate terms:


f676_0_main_Load(x1, x2, x3, x4) → f676_0_main_Load(x2, x3, x4)
Cond_f676_0_main_Load(x1, x2, x3, x4, x5) → Cond_f676_0_main_Load(x1, x3, x4, x5)

Prepared 1 rules for path length conversion:

P rules:
f676_0_main_Load(x1, x2, x0) → f676_0_main_Load(x1, +(x2, x1), x0) | &&(&&(>(+(x2, 1), 0), >(x1, 0)), <=(x2, x0))

Finished conversion. Obtained 1 rules.

P rules:
f676_0_main_Load(x0, x1, x2) → f676_0_main_Load(x0, +(x1, x0), x2) | &&(&&(>=(x2, x1), >(x0, 0)), >(x1, -1))

(6) Obligation:

Rules:
f676_0_main_Load(x0, x1, x2) → f676_0_main_Load(x0, +(x1, x0), x2) | &&(&&(>=(x2, x1), >(x0, 0)), >(x1, -1))

(7) PolynomialOrderProcessor (EQUIVALENT transformation)

Found the following polynomial interpretation:


[f676_0_main_Load(x4, x6, x8)] = -x6 + x8

Therefore the following rule(s) have been dropped:


f676_0_main_Load(x0, x1, x2) → f676_0_main_Load(x0, +(x1, x0), x2) | &&(&&(>=(x2, x1), >(x0, 0)), >(x1, -1))

(8) YES