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var GlobalFlag: bool;
const A: int;
const B: int;
const C: int;
procedure Join(b: bool);
modifies GlobalFlag;
implementation Join(b: bool)
{
var x: int;
var y: int;
var z: int;
start:
assume {:inferred} true;
GlobalFlag := true;
x := 3;
y := 4;
z := x + y;
assume {:inferred} GlobalFlag && x == 3 && y == 4 && z == 7;
goto Then, Else;
Else:
assume {:inferred} GlobalFlag && x == 3 && y == 4 && z == 7;
assume b <==> false;
y := 4;
assume {:inferred} GlobalFlag && x == 3 && y == 4 && z == 7 && !b;
goto join;
join:
assume {:inferred} GlobalFlag && 3 <= x && x < 5 && y == 4 && z == 7;
assert y == 4;
assert z == 7;
assert GlobalFlag <==> true;
assume {:inferred} GlobalFlag && 3 <= x && x < 5 && y == 4 && z == 7;
return;
Then:
assume {:inferred} GlobalFlag && x == 3 && y == 4 && z == 7;
assume b <==> true;
x := x + 1;
assume {:inferred} GlobalFlag && x == 4 && y == 4 && z == 7 && b;
goto join;
}
procedure Loop();
implementation Loop()
{
var c: int;
var i: int;
start:
assume {:inferred} true;
c := 0;
i := 0;
assume {:inferred} c == 0 && i == 0;
goto test;
test: // cut point
assume {:inferred} c == 0 && 0 <= i && i < 11;
assume {:inferred} c == 0 && 0 <= i && i < 11;
goto Then, Else;
Else:
assume {:inferred} c == 0 && 0 <= i && i < 11;
assume {:inferred} c == 0 && 0 <= i && i < 11;
return;
Then:
assume {:inferred} c == 0 && 0 <= i && i < 11;
assume i < 10;
i := i + 1;
assume {:inferred} c == 0 && 1 <= i && i < 11;
goto test;
}
procedure Evaluate();
implementation Evaluate()
{
var i: int;
start:
assume {:inferred} true;
i := 5;
i := 3 * i + 1;
i := 3 * (i + 1);
i := 1 + 3 * i;
i := (i + 1) * 3;
assume {:inferred} i == 465;
return;
}
Boogie program verifier finished with 0 verified, 0 errors
Intervals.bpl(62,3): Error BP5001: This assertion might not hold.
Execution trace:
Intervals.bpl(57,5): anon0
Intervals.bpl(58,3): anon3_LoopHead
Intervals.bpl(58,3): anon3_LoopDone
Intervals.bpl(73,3): Error BP5001: This assertion might not hold.
Execution trace:
Intervals.bpl(68,5): anon0
Intervals.bpl(69,3): anon3_LoopHead
Intervals.bpl(69,3): anon3_LoopDone
Boogie program verifier finished with 4 verified, 2 errors
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