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// RUN: %boogie -noinfer -typeEncoding:m -useArrayTheory "%s" > "%t"
// RUN: %diff "%s.expect" "%t"
var {:layer 0,2} b: int;
procedure {:yields} {:layer 2} main()
{
yield;
while (*)
{
async call Customer();
yield;
}
yield;
}
procedure {:yields} {:layer 2} Customer()
{
yield;
while (*)
{
call Enter();
yield;
call Leave();
yield;
}
yield;
}
procedure {:yields} {:layer 1,2} Enter()
ensures {:atomic} |{ A: assume b == 0; b := 1; return true; }|;
{
var _old, curr: int;
yield;
while (true) {
call _old := CAS(0, 1);
yield;
if (_old == 0) {
break;
}
while (true) {
call curr := Read();
yield;
if (curr == 0) {
break;
}
}
yield;
}
yield;
}
procedure {:yields} {:layer 0,2} Read() returns (val: int);
ensures {:atomic} |{ A: val := b; return true; }|;
procedure {:yields} {:layer 0,2} CAS(prev: int, next: int) returns (_old: int);
ensures {:atomic} |{
A: _old := b; goto B, C;
B: assume _old == prev; b := next; return true;
C: assume _old != prev; return true;
}|;
procedure {:yields} {:layer 0,2} Leave();
ensures {:atomic} |{ A: b := 0; return true; }|;
|
