(0) Obligation:

JBC Problem based on JBC Program:
Manifest-Version: 1.0 Created-By: 1.6.0_14 (Sun Microsystems Inc.) Main-Class: LogRecursive
public class LogRecursive {
public static void main(String[] args) {
Random.args = args;
log(Random.random(), Random.random());
}

public static int log(int x, int y) {
if (x >= y && y > 1) {
return 1 + log(x/y, y);
}
return 0;
}
}


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

public static int random() {
if (args.length <= index) {
return 0;
}
String string = args[index];
index++;
if (string == null) {
return 0;
}
return string.length();
}
}


(1) JBC2FIG (SOUND transformation)

Constructed FIGraph.

(2) Obligation:

FIGraph based on JBC Program:
LogRecursive.main([Ljava/lang/String;)V: Graph of 118 nodes with 0 SCCs.

LogRecursive.log(II)I: Graph of 34 nodes with 0 SCCs.


(3) FIGtoITRSProof (SOUND transformation)

Transformed FIGraph SCCs to IDPs. Logs:


Log for SCC 0:

Generated 16 rules for P and 17 rules for R.


Combined rules. Obtained 1 rules for P and 3 rules for R.


Filtered ground terms:


529_1_log_InvokeMethod(x1, x2, x3, x4) → 529_1_log_InvokeMethod(x1, x3, x4)
464_0_log_Load(x1, x2, x3, x4) → 464_0_log_Load(x2, x3, x4)
Cond_464_0_log_Load(x1, x2, x3, x4, x5) → Cond_464_0_log_Load(x1, x3, x4, x5)
688_0_log_Return(x1) → 688_0_log_Return
541_0_log_Return(x1, x2) → 541_0_log_Return
475_0_log_Return(x1) → 475_0_log_Return

Filtered duplicate args:


464_0_log_Load(x1, x2, x3) → 464_0_log_Load(x2, x3)
Cond_464_0_log_Load(x1, x2, x3, x4) → Cond_464_0_log_Load(x1, x3, x4)

Filtered unneeded arguments:


529_1_log_InvokeMethod(x1, x2, x3) → 529_1_log_InvokeMethod(x1)

Combined rules. Obtained 1 rules for P and 3 rules for R.


Finished conversion. Obtained 1 rules for P and 3 rules for R. System has predefined symbols.


(4) Obligation:

IDP problem:
The following function symbols are pre-defined:
!=~Neq: (Integer, Integer) -> Boolean
*~Mul: (Integer, Integer) -> Integer
>=~Ge: (Integer, Integer) -> Boolean
-1~UnaryMinus: (Integer) -> Integer
|~Bwor: (Integer, Integer) -> Integer
/~Div: (Integer, Integer) -> Integer
=~Eq: (Integer, Integer) -> Boolean
~Bwxor: (Integer, Integer) -> Integer
||~Lor: (Boolean, Boolean) -> Boolean
!~Lnot: (Boolean) -> Boolean
<~Lt: (Integer, Integer) -> Boolean
-~Sub: (Integer, Integer) -> Integer
<=~Le: (Integer, Integer) -> Boolean
>~Gt: (Integer, Integer) -> Boolean
~~Bwnot: (Integer) -> Integer
%~Mod: (Integer, Integer) -> Integer
&~Bwand: (Integer, Integer) -> Integer
+~Add: (Integer, Integer) -> Integer
&&~Land: (Boolean, Boolean) -> Boolean


The following domains are used:

Boolean, Integer


The ITRS R consists of the following rules:
529_1_log_InvokeMethod(475_0_log_Return) → 541_0_log_Return
529_1_log_InvokeMethod(541_0_log_Return) → 688_0_log_Return
529_1_log_InvokeMethod(688_0_log_Return) → 688_0_log_Return

The integer pair graph contains the following rules and edges:
(0): 464_0_LOG_LOAD(x1[0], x0[0]) → COND_464_0_LOG_LOAD(x1[0] > 1 && x1[0] <= x0[0], x1[0], x0[0])
(1): COND_464_0_LOG_LOAD(TRUE, x1[1], x0[1]) → 464_0_LOG_LOAD(x1[1], x0[1] / x1[1])

(0) -> (1), if ((x1[0] > 1 && x1[0] <= x0[0]* TRUE)∧(x1[0]* x1[1])∧(x0[0]* x0[1]))


(1) -> (0), if ((x1[1]* x1[0])∧(x0[1] / x1[1]* x0[0]))



The set Q consists of the following terms:
529_1_log_InvokeMethod(475_0_log_Return)
529_1_log_InvokeMethod(541_0_log_Return)
529_1_log_InvokeMethod(688_0_log_Return)

(5) IDPNonInfProof (SOUND transformation)

The constraints were generated the following way:
The DP Problem is simplified using the Induction Calculus [NONINF] with the following steps:
Note that final constraints are written in bold face.


For Pair 464_0_LOG_LOAD(x1, x0) → COND_464_0_LOG_LOAD(&&(>(x1, 1), <=(x1, x0)), x1, x0) the following chains were created:
  • We consider the chain 464_0_LOG_LOAD(x1[0], x0[0]) → COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0]), COND_464_0_LOG_LOAD(TRUE, x1[1], x0[1]) → 464_0_LOG_LOAD(x1[1], /(x0[1], x1[1])) which results in the following constraint:

    (1)    (&&(>(x1[0], 1), <=(x1[0], x0[0]))=TRUEx1[0]=x1[1]x0[0]=x0[1]464_0_LOG_LOAD(x1[0], x0[0])≥NonInfC∧464_0_LOG_LOAD(x1[0], x0[0])≥COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])∧(UIncreasing(COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])), ≥))



    We simplified constraint (1) using rules (IV), (IDP_BOOLEAN) which results in the following new constraint:

    (2)    (>(x1[0], 1)=TRUE<=(x1[0], x0[0])=TRUE464_0_LOG_LOAD(x1[0], x0[0])≥NonInfC∧464_0_LOG_LOAD(x1[0], x0[0])≥COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])∧(UIncreasing(COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])), ≥))



    We simplified constraint (2) using rule (POLY_CONSTRAINTS) which results in the following new constraint:

    (3)    (x1[0] + [-2] ≥ 0∧x0[0] + [-1]x1[0] ≥ 0 ⇒ (UIncreasing(COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])), ≥)∧[(-1)bni_18 + (-1)Bound*bni_18] + [bni_18]x0[0] + [(-1)bni_18]x1[0] ≥ 0∧[(-1)bso_19] ≥ 0)



    We simplified constraint (3) using rule (IDP_POLY_SIMPLIFY) which results in the following new constraint:

    (4)    (x1[0] + [-2] ≥ 0∧x0[0] + [-1]x1[0] ≥ 0 ⇒ (UIncreasing(COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])), ≥)∧[(-1)bni_18 + (-1)Bound*bni_18] + [bni_18]x0[0] + [(-1)bni_18]x1[0] ≥ 0∧[(-1)bso_19] ≥ 0)



    We simplified constraint (4) using rule (POLY_REMOVE_MIN_MAX) which results in the following new constraint:

    (5)    (x1[0] + [-2] ≥ 0∧x0[0] + [-1]x1[0] ≥ 0 ⇒ (UIncreasing(COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])), ≥)∧[(-1)bni_18 + (-1)Bound*bni_18] + [bni_18]x0[0] + [(-1)bni_18]x1[0] ≥ 0∧[(-1)bso_19] ≥ 0)



    We simplified constraint (5) using rule (IDP_SMT_SPLIT) which results in the following new constraint:

    (6)    (x1[0] ≥ 0∧x0[0] + [-2] + [-1]x1[0] ≥ 0 ⇒ (UIncreasing(COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])), ≥)∧[(-3)bni_18 + (-1)Bound*bni_18] + [bni_18]x0[0] + [(-1)bni_18]x1[0] ≥ 0∧[(-1)bso_19] ≥ 0)



    We simplified constraint (6) using rule (IDP_SMT_SPLIT) which results in the following new constraint:

    (7)    (x1[0] ≥ 0∧x0[0] ≥ 0 ⇒ (UIncreasing(COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])), ≥)∧[(-1)bni_18 + (-1)Bound*bni_18] + [bni_18]x0[0] ≥ 0∧[(-1)bso_19] ≥ 0)







For Pair COND_464_0_LOG_LOAD(TRUE, x1, x0) → 464_0_LOG_LOAD(x1, /(x0, x1)) the following chains were created:
  • We consider the chain 464_0_LOG_LOAD(x1[0], x0[0]) → COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0]), COND_464_0_LOG_LOAD(TRUE, x1[1], x0[1]) → 464_0_LOG_LOAD(x1[1], /(x0[1], x1[1])), 464_0_LOG_LOAD(x1[0], x0[0]) → COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0]) which results in the following constraint:

    (8)    (&&(>(x1[0], 1), <=(x1[0], x0[0]))=TRUEx1[0]=x1[1]x0[0]=x0[1]x1[1]=x1[0]1/(x0[1], x1[1])=x0[0]1COND_464_0_LOG_LOAD(TRUE, x1[1], x0[1])≥NonInfC∧COND_464_0_LOG_LOAD(TRUE, x1[1], x0[1])≥464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))∧(UIncreasing(464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))), ≥))



    We simplified constraint (8) using rules (III), (IV), (IDP_BOOLEAN) which results in the following new constraint:

    (9)    (>(x1[0], 1)=TRUE<=(x1[0], x0[0])=TRUECOND_464_0_LOG_LOAD(TRUE, x1[0], x0[0])≥NonInfC∧COND_464_0_LOG_LOAD(TRUE, x1[0], x0[0])≥464_0_LOG_LOAD(x1[0], /(x0[0], x1[0]))∧(UIncreasing(464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))), ≥))



    We simplified constraint (9) using rule (POLY_CONSTRAINTS) which results in the following new constraint:

    (10)    (x1[0] + [-2] ≥ 0∧x0[0] + [-1]x1[0] ≥ 0 ⇒ (UIncreasing(464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))), ≥)∧[(-1)bni_20 + (-1)Bound*bni_20] + [bni_20]x0[0] + [(-1)bni_20]x1[0] ≥ 0∧[(-1)bso_24] + x0[0] + [-1]max{x0[0], [-1]x0[0]} + min{max{x1[0], [-1]x1[0]} + [-1], max{x0[0], [-1]x0[0]}} ≥ 0)



    We simplified constraint (10) using rule (IDP_POLY_SIMPLIFY) which results in the following new constraint:

    (11)    (x1[0] + [-2] ≥ 0∧x0[0] + [-1]x1[0] ≥ 0 ⇒ (UIncreasing(464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))), ≥)∧[(-1)bni_20 + (-1)Bound*bni_20] + [bni_20]x0[0] + [(-1)bni_20]x1[0] ≥ 0∧[(-1)bso_24] + x0[0] + [-1]max{x0[0], [-1]x0[0]} + min{max{x1[0], [-1]x1[0]} + [-1], max{x0[0], [-1]x0[0]}} ≥ 0)



    We simplified constraint (11) using rule (POLY_REMOVE_MIN_MAX) which results in the following new constraint:

    (12)    (x1[0] + [-2] ≥ 0∧x0[0] + [-1]x1[0] ≥ 0∧[2]x0[0] ≥ 0∧[2]x1[0] ≥ 0 ⇒ (UIncreasing(464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))), ≥)∧[(-1)bni_20 + (-1)Bound*bni_20] + [bni_20]x0[0] + [(-1)bni_20]x1[0] ≥ 0∧[-1 + (-1)bso_24] + x1[0] ≥ 0)



    We simplified constraint (12) using rule (IDP_SMT_SPLIT) which results in the following new constraint:

    (13)    (x1[0] ≥ 0∧x0[0] + [-2] + [-1]x1[0] ≥ 0∧[2]x0[0] ≥ 0∧[4] + [2]x1[0] ≥ 0 ⇒ (UIncreasing(464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))), ≥)∧[(-3)bni_20 + (-1)Bound*bni_20] + [bni_20]x0[0] + [(-1)bni_20]x1[0] ≥ 0∧[1 + (-1)bso_24] + x1[0] ≥ 0)



    We simplified constraint (13) using rule (IDP_SMT_SPLIT) which results in the following new constraint:

    (14)    (x1[0] ≥ 0∧x0[0] ≥ 0∧[4] + [2]x1[0] + [2]x0[0] ≥ 0∧[4] + [2]x1[0] ≥ 0 ⇒ (UIncreasing(464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))), ≥)∧[(-1)bni_20 + (-1)Bound*bni_20] + [bni_20]x0[0] ≥ 0∧[1 + (-1)bso_24] + x1[0] ≥ 0)



    We simplified constraint (14) using rule (IDP_POLY_GCD) which results in the following new constraint:

    (15)    (x1[0] ≥ 0∧x0[0] ≥ 0∧[2] + x1[0] + x0[0] ≥ 0∧[2] + x1[0] ≥ 0 ⇒ (UIncreasing(464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))), ≥)∧[(-1)bni_20 + (-1)Bound*bni_20] + [bni_20]x0[0] ≥ 0∧[1 + (-1)bso_24] + x1[0] ≥ 0)







To summarize, we get the following constraints P for the following pairs.
  • 464_0_LOG_LOAD(x1, x0) → COND_464_0_LOG_LOAD(&&(>(x1, 1), <=(x1, x0)), x1, x0)
    • (x1[0] ≥ 0∧x0[0] ≥ 0 ⇒ (UIncreasing(COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])), ≥)∧[(-1)bni_18 + (-1)Bound*bni_18] + [bni_18]x0[0] ≥ 0∧[(-1)bso_19] ≥ 0)

  • COND_464_0_LOG_LOAD(TRUE, x1, x0) → 464_0_LOG_LOAD(x1, /(x0, x1))
    • (x1[0] ≥ 0∧x0[0] ≥ 0∧[2] + x1[0] + x0[0] ≥ 0∧[2] + x1[0] ≥ 0 ⇒ (UIncreasing(464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))), ≥)∧[(-1)bni_20 + (-1)Bound*bni_20] + [bni_20]x0[0] ≥ 0∧[1 + (-1)bso_24] + x1[0] ≥ 0)




The constraints for P> respective Pbound are constructed from P where we just replace every occurence of "t ≥ s" in P by "t > s" respective "t ≥ c". Here c stands for the fresh constant used for Pbound.
Using the following integer polynomial ordering the resulting constraints can be solved
Polynomial interpretation over integers[POLO]:

POL(TRUE) = [2]   
POL(FALSE) = [3]   
POL(529_1_log_InvokeMethod(x1)) = [-1] + [-1]x1   
POL(475_0_log_Return) = [-1]   
POL(541_0_log_Return) = [-1]   
POL(688_0_log_Return) = [-1]   
POL(464_0_LOG_LOAD(x1, x2)) = [-1] + x2 + [-1]x1   
POL(COND_464_0_LOG_LOAD(x1, x2, x3)) = [-1] + x3 + [-1]x2   
POL(&&(x1, x2)) = 0   
POL(>(x1, x2)) = [-1]   
POL(1) = [1]   
POL(<=(x1, x2)) = [-1]   

Polynomial Interpretations with Context Sensitive Arithemetic Replacement
POL(TermCSAR-Mode @ Context)

POL(/(x1, x1[0])1 @ {464_0_LOG_LOAD_2/1}) = max{x1, [-1]x1} + [-1]min{max{x2, [-1]x2} + [-1], max{x1, [-1]x1}}   

The following pairs are in P>:

COND_464_0_LOG_LOAD(TRUE, x1[1], x0[1]) → 464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))

The following pairs are in Pbound:

464_0_LOG_LOAD(x1[0], x0[0]) → COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])
COND_464_0_LOG_LOAD(TRUE, x1[1], x0[1]) → 464_0_LOG_LOAD(x1[1], /(x0[1], x1[1]))

The following pairs are in P:

464_0_LOG_LOAD(x1[0], x0[0]) → COND_464_0_LOG_LOAD(&&(>(x1[0], 1), <=(x1[0], x0[0])), x1[0], x0[0])

At least the following rules have been oriented under context sensitive arithmetic replacement:

FALSE1&&(FALSE, FALSE)1
/1

(6) Obligation:

IDP problem:
The following function symbols are pre-defined:
!=~Neq: (Integer, Integer) -> Boolean
*~Mul: (Integer, Integer) -> Integer
>=~Ge: (Integer, Integer) -> Boolean
-1~UnaryMinus: (Integer) -> Integer
|~Bwor: (Integer, Integer) -> Integer
/~Div: (Integer, Integer) -> Integer
=~Eq: (Integer, Integer) -> Boolean
~Bwxor: (Integer, Integer) -> Integer
||~Lor: (Boolean, Boolean) -> Boolean
!~Lnot: (Boolean) -> Boolean
<~Lt: (Integer, Integer) -> Boolean
-~Sub: (Integer, Integer) -> Integer
<=~Le: (Integer, Integer) -> Boolean
>~Gt: (Integer, Integer) -> Boolean
~~Bwnot: (Integer) -> Integer
%~Mod: (Integer, Integer) -> Integer
&~Bwand: (Integer, Integer) -> Integer
+~Add: (Integer, Integer) -> Integer
&&~Land: (Boolean, Boolean) -> Boolean


The following domains are used:

Boolean, Integer


The ITRS R consists of the following rules:
529_1_log_InvokeMethod(475_0_log_Return) → 541_0_log_Return
529_1_log_InvokeMethod(541_0_log_Return) → 688_0_log_Return
529_1_log_InvokeMethod(688_0_log_Return) → 688_0_log_Return

The integer pair graph contains the following rules and edges:
(0): 464_0_LOG_LOAD(x1[0], x0[0]) → COND_464_0_LOG_LOAD(x1[0] > 1 && x1[0] <= x0[0], x1[0], x0[0])


The set Q consists of the following terms:
529_1_log_InvokeMethod(475_0_log_Return)
529_1_log_InvokeMethod(541_0_log_Return)
529_1_log_InvokeMethod(688_0_log_Return)

(7) IDependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 1 less node.

(8) TRUE