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// VC generation tests: passification
procedure good0(x: int) returns (y: int, z: int)
ensures z == 4 || z == 4+x;
{
var t: int;
A:
t := y;
z := 3;
goto B, C;
B:
z := z + x;
goto D;
C:
goto D;
D:
z := z + 1;
y := t;
return;
}
procedure good1(x: int) returns (y: int, z: int)
ensures z == x + 4;
{
var t: int;
A:
t := y;
z := 3;
z := z + x;
z := z + 1;
y := t;
return;
}
procedure bad0(x: int) returns (y: int, z: int)
ensures y == 4; // ERROR: postcondition violation
{
var t: int;
A:
t := z;
z := 3;
z := z + 1;
y := t;
return;
}
procedure Loop()
{
start:
goto start;
}
procedure UnreachableBlock()
{
start:
return;
notReached:
goto start;
reallyNeverReached:
goto reallyNeverReached;
}
procedure Loop0() returns (z: int)
ensures 10 <= z;
{
var x: int;
A:
goto B, C;
B:
assume x < 10;
x := x + 1;
goto A;
C:
assume !(x < 10);
z := x;
return;
}
const unique A0: name;
const unique A1: name;
const unique A2: name;
procedure Array0() returns (z: int)
ensures z >= 5;
{
var a: [name,name]int;
L0:
a[A0,A2] := 5;
a[A0,A1] := 20;
assert a[A0,A1] == 20;
goto L1,L2;
L1:
a[A0,A2] := 18;
assert a[A0,A2] == 18;
goto L2;
L2:
assert a[A0,A1] == 20;
z := a[A0,A2];
return;
}
procedure Array1(o0: ref, o1: ref) returns (z: int)
ensures z >= 5;
{
var a: [ref,name]int;
L0:
a[o1,A0] := 5;
a[o0,A0] := 20;
assert a[o0,A0] == 20;
goto L1,L2;
L1:
a[o1,A0] := 18;
assert a[o1,A0] == 18;
goto L2;
L2:
assert a[o0,A0] == 20; // ERROR: assertion failure
z := a[o1,A0];
return;
}
procedure Array2(o0: ref, o1: ref) returns (z: int)
ensures z >= 5;
{
var a: [ref,name]int;
L0:
assume o1 != o0;
a[o1,A0] := 5;
a[o0,A0] := 20;
assert a[o0,A0] == 20;
goto L1,L2;
L1:
a[o1,A0] := 18;
assert a[o1,A0] == 18;
goto L2;
L2:
assert a[o0,A0] == 20;
z := a[o1,A0];
return;
}
procedure P()
{
var t: int;
L0:
t := 0;
goto L1, L2;
L1:
t := 1;
goto L2;
L2:
assert t == 1; // ERROR: assert failure
return;
}
procedure Q()
{
var t: int;
L0:
t := 0;
goto L1, L2;
L1:
t := 1;
goto L2;
L2:
assert t == 0; // ERROR: assert failure
return;
}
type name, ref;
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