public void BranchConditionalAccessDefiniteAssignment()
{
if (conditional_access == null)
{
conditional_access = BranchDefiniteAssignment();
}
}
public static DefiniteAssignmentBitSet operator |(DefiniteAssignmentBitSet a, DefiniteAssignmentBitSet b)
{
if (AreEqual(a, b))
{
return(a);
}
DefiniteAssignmentBitSet res;
if (a.large_bits == null)
{
res = new DefiniteAssignmentBitSet(a);
res.bits |= b.bits;
res.bits &= ~copy_on_write_flag;
return(res);
}
res = new DefiniteAssignmentBitSet(a);
res.Clone();
var dest = res.large_bits;
var src = b.large_bits;
for (int i = 0; i < dest.Length; ++i)
{
dest[i] |= src[i];
}
return(res);
}
public DefiniteAssignmentBitSet BranchDefiniteAssignment(DefiniteAssignmentBitSet da)
{
if (da != DefiniteAssignmentBitSet.Empty)
{
DefiniteAssignment = new DefiniteAssignmentBitSet(da);
}
return(da);
}
public bool IsAssigned(DefiniteAssignmentBitSet vector)
{
if (vector == null)
{
return(true);
}
if (vector [Offset])
{
return(true);
}
// Unless this is a struct
if (!TypeInfo.IsStruct)
{
return(false);
}
//
// Following case cannot be handled fully by SetStructFieldAssigned
// because we may encounter following case
//
// struct A { B b }
// struct B { int value; }
//
// setting a.b.value is propagated only to B's vector and not upwards to possible parents
//
//
// Each field must be assigned
//
for (int i = Offset + 1; i <= TypeInfo.Length + Offset; i++)
{
if (!vector[i])
{
return(false);
}
}
// Ok, now check all fields which are structs.
for (int i = 0; i < sub_info.Length; i++)
{
VariableInfo sinfo = sub_info[i];
if (sinfo == null)
{
continue;
}
if (!sinfo.IsAssigned(vector))
{
return(false);
}
}
vector.Set(Offset);
return(true);
}
public bool IsStructFieldAssigned(DefiniteAssignmentBitSet vector, string field_name)
{
int field_idx = TypeInfo.GetFieldIndex(field_name);
if (field_idx == 0)
{
return(true);
}
return(vector [Offset + field_idx]);
}
public DefiniteAssignmentBitSet(DefiniteAssignmentBitSet source)
{
if (source.large_bits != null)
{
large_bits = source.large_bits;
bits = source.bits | copy_on_write_flag;
}
else
{
bits = source.bits & ~copy_on_write_flag;
}
}
public static DefiniteAssignmentBitSet And(List <DefiniteAssignmentBitSet> das)
{
if (das.Count == 0)
{
throw new ArgumentException("Empty das");
}
DefiniteAssignmentBitSet res = das[0];
for (int i = 1; i < das.Count; ++i)
{
res &= das[i];
}
return(res);
}
public void SetAssigned(DefiniteAssignmentBitSet vector, bool generatedAssignment)
{
if (Length == 1)
{
vector.Set(Offset);
}
else
{
vector.Set(Offset, Length);
}
if (!generatedAssignment)
{
IsEverAssigned = true;
}
}
public static bool AreEqual(DefiniteAssignmentBitSet a, DefiniteAssignmentBitSet b)
{
if (a.large_bits == null)
{
return((a.bits & ~copy_on_write_flag) == (b.bits & ~copy_on_write_flag));
}
for (int i = 0; i < a.large_bits.Length; ++i)
{
if (a.large_bits[i] != b.large_bits[i])
{
return(false);
}
}
return(true);
}
public void SetStructFieldAssigned(DefiniteAssignmentBitSet vector, string field_name)
{
if (vector [Offset])
{
return;
}
int field_idx = TypeInfo.GetFieldIndex(field_name);
if (field_idx == 0)
{
return;
}
var complex_field = TypeInfo.GetStructField(field_name);
if (complex_field != null)
{
vector.Set(Offset + complex_field.Offset, complex_field.TotalLength);
}
else
{
vector.Set(Offset + field_idx);
}
IsEverAssigned = true;
//
// Each field must be assigned before setting master bit
//
for (int i = Offset + 1; i < TypeInfo.TotalLength + Offset; i++)
{
if (!vector[i])
{
return;
}
}
//
// Set master struct flag to assigned when all tested struct
// fields have been assigned
//
vector.Set(Offset);
}
public bool AddReachedLabel(Statement label)
{
List <DefiniteAssignmentBitSet> das;
if (LabelStack == null)
{
LabelStack = new Dictionary <Statement, List <DefiniteAssignmentBitSet> > ();
das = null;
}
else
{
LabelStack.TryGetValue(label, out das);
}
if (das == null)
{
das = new List <DefiniteAssignmentBitSet> ();
das.Add(new DefiniteAssignmentBitSet(DefiniteAssignment));
LabelStack.Add(label, das);
return(false);
}
foreach (var existing in das)
{
if (DefiniteAssignmentBitSet.AreEqual(existing, DefiniteAssignment))
{
return(true);
}
}
if (DefiniteAssignment == DefiniteAssignmentBitSet.Empty)
{
das.Add(DefiniteAssignment);
}
else
{
das.Add(new DefiniteAssignmentBitSet(DefiniteAssignment));
}
return(false);
}
public DefiniteAssignmentBitSet BranchDefiniteAssignment (DefiniteAssignmentBitSet da)
{
if (da != DefiniteAssignmentBitSet.Empty) {
DefiniteAssignment = new DefiniteAssignmentBitSet (da);
}
return da;
}
public void ConditionalAccessEnd()
{
Debug.Assert(conditional_access != null);
DefiniteAssignment = conditional_access;
conditional_access = null;
}
public void SetAssigned (DefiniteAssignmentBitSet vector, bool generatedAssignment)
{
if (Length == 1)
vector.Set (Offset);
else
vector.Set (Offset, Length);
if (!generatedAssignment)
IsEverAssigned = true;
}
public void SetStructFieldAssigned (DefiniteAssignmentBitSet vector, string field_name)
{
if (vector [Offset])
return;
int field_idx = TypeInfo.GetFieldIndex (field_name);
if (field_idx == 0)
return;
var complex_field = TypeInfo.GetStructField (field_name);
if (complex_field != null) {
vector.Set (Offset + complex_field.Offset, complex_field.TotalLength);
} else {
vector.Set (Offset + field_idx);
}
IsEverAssigned = true;
//
// Each field must be assigned before setting master bit
//
for (int i = Offset + 1; i < TypeInfo.TotalLength + Offset; i++) {
if (!vector[i])
return;
}
//
// Set master struct flag to assigned when all tested struct
// fields have been assigned
//
vector.Set (Offset);
}
public DefiniteAssignmentBitSet (DefiniteAssignmentBitSet source)
{
if (source.large_bits != null) {
large_bits = source.large_bits;
bits = source.bits | copy_on_write_flag;
} else {
bits = source.bits & ~copy_on_write_flag;
}
}
public static DefiniteAssignmentBitSet operator | (DefiniteAssignmentBitSet a, DefiniteAssignmentBitSet b)
{
if (AreEqual (a, b))
return a;
DefiniteAssignmentBitSet res;
if (a.large_bits == null) {
res = new DefiniteAssignmentBitSet (a);
res.bits |= b.bits;
res.bits &= ~copy_on_write_flag;
return res;
}
res = new DefiniteAssignmentBitSet (a);
res.Clone ();
var dest = res.large_bits;
var src = b.large_bits;
for (int i = 0; i < dest.Length; ++i) {
dest[i] |= src[i];
}
return res;
}
public static bool AreEqual (DefiniteAssignmentBitSet a, DefiniteAssignmentBitSet b)
{
if (a.large_bits == null)
return (a.bits & ~copy_on_write_flag) == (b.bits & ~copy_on_write_flag);
for (int i = 0; i < a.large_bits.Length; ++i) {
if (a.large_bits[i] != b.large_bits[i])
return false;
}
return true;
}
public bool IsStructFieldAssigned (DefiniteAssignmentBitSet vector, string field_name)
{
int field_idx = TypeInfo.GetFieldIndex (field_name);
if (field_idx == 0)
return true;
return vector [Offset + field_idx];
}
public void BranchConditionalAccessDefiniteAssignment ()
{
if (conditional_access == null)
conditional_access = BranchDefiniteAssignment ();
}
public void ConditionalAccessEnd ()
{
Debug.Assert (conditional_access != null);
DefiniteAssignment = conditional_access;
conditional_access = null;
}
public bool IsAssigned (DefiniteAssignmentBitSet vector)
{
if (vector == null)
return true;
if (vector [Offset])
return true;
// Unless this is a struct
if (!TypeInfo.IsStruct)
return false;
//
// Following case cannot be handled fully by SetStructFieldAssigned
// because we may encounter following case
//
// struct A { B b }
// struct B { int value; }
//
// setting a.b.value is propagated only to B's vector and not upwards to possible parents
//
//
// Each field must be assigned
//
for (int i = Offset + 1; i <= TypeInfo.Length + Offset; i++) {
if (!vector[i])
return false;
}
// Ok, now check all fields which are structs.
for (int i = 0; i < sub_info.Length; i++) {
VariableInfo sinfo = sub_info[i];
if (sinfo == null)
continue;
if (!sinfo.IsAssigned (vector))
return false;
}
vector.Set (Offset);
return true;
}