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// Test formula-term distinction in Simplify
procedure plus(x: int, y: int) returns (z: int);
ensures z == x + y;
implementation plus(x: int, y: int) returns (z: int)
{
start:
assume z == 3;
return; // ERROR: postcondition possibly violated
}
implementation plus(x: int, y: int) returns (z: int)
{
start:
z := x + y;
return;
}
implementation plus(x: int, y: int) returns (z: int)
{
start:
z := x + y;
z := 0 + z;
return;
}
procedure plus2(x: int, y: int) returns (z: int)
ensures z == x + y;
{
start:
z := x + y;
return;
}
procedure or(x: int, y: int, a: int, b: int) returns (z: int)
requires a == b;
{
var t: bool;
start:
t := (x < y || x > y || x == y || x != y) && a >= b && a <= b;
assert (x < y || x > y || x == y || x != y) && a >= b && a <= b;
assert t;
return;
}
procedure less(x: int, y: int) returns (z: bool);
requires x < y;
ensures z == (x < y);
implementation less(x: int, y: int) returns (z: bool)
{
start:
z := x < y;
return;
}
implementation less(x: int, y: int) returns (z: bool)
{
start:
goto yes, no;
yes:
assume x < y;
z := true;
return;
no:
assume !(x < y);
z := false;
return;
}
implementation less(x: int, y: int) returns (z: bool)
{
start:
goto yes, no;
yes:
assume x < y;
z := true;
return;
no:
assume x >= y;
z := false;
return;
}
procedure LESS(x: int, y: int) returns (z: bool);
requires x < y;
ensures z <==> (x < y);
implementation LESS(x: int, y: int) returns (z: bool)
{
start:
z := x < y;
return;
}
implementation LESS(x: int, y: int) returns (z: bool)
{
start:
goto yes, no;
yes:
assume x < y;
z := true;
return;
no:
assume !(x < y);
z := false;
return;
}
implementation LESS(x: int, y: int) returns (z: bool)
{
start:
goto yes, no;
yes:
assume x < y;
z := true;
return;
no:
assume x >= y;
z := false;
return;
}
procedure Assignments()
{
var b: bool;
var c: bool;
var d: bool;
var x: bool, y: bool;
entry:
b := c || d;
b := c && d;
x := c <==> d;
y := c ==> d;
assert x ==> y;
return;
}
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