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// RUN: %boogie -noVerify "%s" > "%t"
// RUN: %diff "%s.expect" "%t"
var one: [int]int;
var two: [int, int]int;
procedure Good0(x: int, y: int)
requires one[x] == two[x,y];
modifies one, two;
{
start:
one[x] := two[x,y];
two[x,y] := one[x];
return;
}
procedure Bad0(x: int, y: int)
requires one[x,y] == 7;
requires two[x] == 8;
modifies one, two;
{
start:
one[x,y] := 10;
two[x] := 11;
return;
}
var A: [int]bool;
var B: [bool, ref]int;
procedure Good1(x: int, b: bool, o: ref)
requires A[x] && B[b,o] == 18;
modifies A, B;
{
start:
A[x] := true;
B[b,o] := 19;
A[100] := false;
B[false,null] := 70;
return;
}
procedure Bad1(x: int, b: bool, o: ref)
requires A[b];
requires A[x] == 7;
requires B[x,x] < 12;
requires B[b,b] == B[o,o];
requires B[null,5];
requires B[7,7] == A[7];
modifies A, B;
{
start:
A[b] := true;
B[3,14] := null;
A[A[x]] := 9;
B[false,false] := 70;
return;
}
var M: [ [int,int]bool, [name]name ]int;
var Q: [int,int][int]int;
var R: [int][int,int]int;
procedure Good2(k: [int,int]bool, l: [name]name) returns (n: int)
modifies M, Q, R;
{
var m: [ [int,int]bool, [name]name ]int;
var p: [int,int]bool;
var q: [int]int;
var qq: [int,int][int]int;
var r: [int,int]int;
start:
n := M[k,l];
m := M;
p := k;
p[5,8] := true;
m[p,l] := 13;
M := m;
goto next;
next:
qq := Q;
q := Q[13,21];
n := n + Q[34,55][89];
R[1] := R[2];
n := n + R[1][2,3];
Q[144,233] := q;
goto deepUpdate;
deepUpdate:
// To effectively do:
// Q[5,8][13] := 21;
// do:
q := Q[5,8];
q[13] := 21;
Q[5,8] := q;
return;
}
const Sven: name;
const Mia: name;
const Tryggve: name;
const Gunnel: name;
procedure Bad2(k: [int,int]bool, l: [name]name) returns (n: int)
modifies M, Q, R;
{
var m: [ [int,int]bool, [name]name ]int;
var p: [int,int]bool;
var q: [int]int;
var qq: [int,int][int]int;
var qqx: [int,int][name]int;
start:
n := M[Sven,l];
m := p;
p := l[Mia];
p[5,8] := Tryggve;
m[p,Gunnel] := 13;
M := qq;
goto next;
next:
qq := Q; // okay
q := Q[13];
n := n - Q[89][34,55];
Q[true,233] := q;
qqx := qq;
Q := qqx;
qqx := qqx; // okay
Q := Q; // okay
n := n + Q[34,55][144,169];
R[1,2] := 0;
R[1] := R[2,3];
n := n + R[1][2];
n := n + R[1,2];
return;
}
type MyType;
var S0: bool;
var S1: [ref]bool;
var S2: [ref,int]bool;
var S3: [[ref,int]bool,MyType]MyType;
var S4: <a>[int,a]bool;
var S5: [int,int]bool;
var S6: [any,any]bool;
var S7: [int,any]any;
var S8: [any]bool;
function Sf(any) returns (bool);
procedure SubtypesGood(a: any)
modifies S0;
{
var t: MyType;
var b: bool;
start:
S0 := S1[null]; // bool := bool
S0 := S2[null,0]; // bool := bool
t := S3[S2,t];
goto next;
next:
b := S4[4,a];
b := S4[5,null]; // any := ref
b := S4[6,S4]; // any := [int,any]bool
b := Sf(S5);
return;
}
procedure SubtypesBad()
modifies S4,S5,S6;
modifies S8;
{
start:
S4 := S4;
S4 := S5; // no
S5 := S4; // no
S4 := S6; // no
S6 := S4; // no
S8 := S1; // no
return;
}
// ----------------------------------------------------
var ArrayA: [int]bool;
var ArrayB: <a>[a]bool;
procedure ArrayP(x: int, y: any)
requires ArrayA[x];
requires ArrayA[y]; // error
requires ArrayB[x];
requires ArrayB[y];
modifies ArrayA, ArrayB;
{
start:
ArrayA[x] := true;
ArrayA[y] := true; // error
ArrayB[x] := true;
ArrayB[y] := true;
return;
}
// ----------------------------------------------------
procedure IntMethod(p: any) returns (r: int);
procedure AnyMethod(p: int) returns (r: any);
procedure IntMethodCaller()
{
var x: any, y: int;
entry:
call x := AnyMethod(y); // types are exact
call x := IntMethod(y); // error: type mismatch for out-parameter
x := y;
y := x; // error: cannot assign any to int
call y := IntMethod(x); // types are exact
call y := AnyMethod(x); // type error on both in-parameter and out-parameter
return;
}
type ref, any, name;
const null : ref;
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