public TypeRef Glb(RootEnvironment rootEnv, TypeRef other, BoolRef changed)
{
if (IsAssignableTo(rootEnv, other))
{
return(this);
}
else if (other.IsAssignableTo(rootEnv, this))
{
changed.Set();
return(other);
}
else
{
// NOTE: As above
if (rootEnv.Global.NullRef.IsAssignableTo(rootEnv, this) &&
rootEnv.Global.NullRef.IsAssignableTo(rootEnv, other))
{
changed.Set();
return(rootEnv.Global.NullRef);
}
else
{
throw new InvalidOperationException("types have no glb");
}
}
}
public void Unify(RootEnvironment rootEnv, StackEntryState other, BoolRef changed)
{
var type = Type.Lub(rootEnv, other.Type, changed);
var upperBound = default(TypeRef);
if (UpperBound != null && other.UpperBound != null)
{
upperBound = UpperBound.Glb(rootEnv, other.UpperBound, changed);
}
else if (other.UpperBound != null)
{
upperBound = other.UpperBound;
changed.Set();
}
else
{
upperBound = UpperBound;
}
if (upperBound != null && !type.IsAssignableTo(rootEnv, upperBound))
{
throw new InvalidOperationException("stack entries are not unifiable");
}
var pointsTo = PointsTo.Lub(other.PointsTo, changed);
UpperBound = upperBound;
Type = type;
PointsTo = pointsTo;
}
public VariableEffects Lub(VariableEffects other, BoolRef changed)
{
var lubVars = new Map <Identifier, ReadWriteDomain>();
foreach (var kv in vars)
{
var rw = default(ReadWriteDomain);
if (other.vars.TryGetValue(kv.Key, out rw))
{
lubVars.Add(kv.Key, kv.Value.Lub(rw, changed));
}
else
{
lubVars.Add(kv.Key, kv.Value);
}
}
foreach (var kv in other.vars)
{
if (!vars.ContainsKey(kv.Key))
{
lubVars.Add(kv.Key, kv.Value);
changed.Set();
}
}
return(new VariableEffects(lubVars));
}
public void Unify(ArgsLocalsState other, BoolRef changed)
{
foreach (var kv in other.argLocalToPointsTo)
{
var pt = default(PointsTo);
if (!kv.Value.IsBottom)
{
if (argLocalToPointsTo.TryGetValue(kv.Key, out pt))
{
argLocalToPointsTo[kv.Key] = pt.Lub(kv.Value, changed);
}
else
{
changed.Set();
argLocalToPointsTo.Add(kv.Key, kv.Value);
}
}
}
argsAlive.UnionInPlace(other.argsAlive, changed);
localsAlive.UnionInPlace(other.localsAlive, changed);
}
public PointsTo Lub(PointsTo other, BoolRef changed)
{
var thisChanged = new BoolRef();
var args = Args.Lub(other.Args, thisChanged);
var locals = Locals.Lub(other.Locals, thisChanged);
var heap = Heap.Lub(other.Heap, thisChanged);
if (args == null || locals == null || heap == null)
{
return(null);
}
else if (thisChanged.Value)
{
changed.Set();
return(new PointsTo(args, locals, heap));
}
else
{
return(this);
}
}
public Effects Lub(Effects other, BoolRef changed)
{
var thisChanged = new BoolRef();
var vars = Vars.Lub(other.Vars, thisChanged);
var heap = Heap.Lub(other.Heap, thisChanged);
var mayThrow = MayThrow.Lub(other.MayThrow, thisChanged);
if (vars == null || heap == null || mayThrow == null)
{
return(null);
}
if (thisChanged.Value)
{
changed.Set();
return(new Effects(vars, heap, mayThrow));
}
else
{
return(this);
}
}
public Effects Lub(Effects other, BoolRef changed)
{
var thisChanged = new BoolRef();
var args = Args.Lub(other.Args, thisChanged);
var locals = Locals.Lub(other.Locals, thisChanged);
var heap = Heap.Lub(other.Heap, thisChanged);
var mayThrow = MayThrow.Lub(other.MayThrow, thisChanged);
if (args == null || locals == null || heap == null || mayThrow == null)
{
return(null);
}
else if (thisChanged.Value)
{
changed.Set();
return(new Effects(args, locals, heap, mayThrow));
}
else
{
return(this);
}
}
public void SourceToTargetTransition(ArgsLocalsState other, BoolRef changed)
{
// Any pointers in source are pointers in target
foreach (var kv in argLocalToPointsTo)
{
var pt = default(PointsTo);
if (!kv.Value.IsBottom)
{
if (other.argLocalToPointsTo.TryGetValue(kv.Key, out pt))
{
other.argLocalToPointsTo[kv.Key] = pt.Lub(kv.Value, changed);
}
else
{
changed.Set();
other.argLocalToPointsTo.Add(kv.Key, kv.Value);
}
}
}
// Anything alive in target is alive in source
argsAlive.UnionInPlace(other.argsAlive, changed);
localsAlive.UnionInPlace(other.localsAlive, changed);
}
public void SetUpperBound(RootEnvironment rootEnv, TypeRef type, BoolRef changed)
{
var s = type.Style(rootEnv);
if (s is ValueTypeStyle || s is PointerTypeStyle || s is CodePointerTypeStyle)
{
// These types are only assignable to themselves, so no need to remember
// the upper bound, just check it
if (!Type.IsAssignableTo(rootEnv, type))
{
if (s is UnmanagedPointerTypeStyle)
{
throw new InvalidOperationException("unmanaged pointer");
}
else
{
throw new InvalidOperationException("stack entry cannot be generalized");
}
}
}
else
{
var upperBound = UpperBound == null ? type : UpperBound.Glb(rootEnv, type, changed);
if (!Type.IsAssignableTo(rootEnv, upperBound))
{
throw new InvalidOperationException("stack entry cannot be generalized");
}
if (!upperBound.IsEquivalentTo(rootEnv, rootEnv.Global.ObjectRef))
{
if (UpperBound == null)
{
changed.Set();
}
UpperBound = upperBound;
}
}
}
