public void VisitBranch(ConditionalBranch branch)
{
if (m_needsCheck && !m_foundSingle && branch.Index >= 2 && m_numLocks == 1)
{
// Look for the if within the lock:
// call System.Void System.Threading.Monitor::Enter(System.Object)
// ldsfld field
// brtrue 2A
if (branch.Untyped.OpCode.Code == Code.Brtrue || branch.Untyped.OpCode.Code == Code.Brtrue_S)
{
LoadStaticField load = m_info.Instructions[branch.Index - 1] as LoadStaticField;
Call call = m_info.Instructions[branch.Index - 2] as Call;
if (load != null && call != null && call.Target.ToString() == "System.Void System.Threading.Monitor::Enter(System.Object)")
{
m_field = load.Field;
Log.DebugLine(this, "found candidate lock at {0:X2}", branch.Untyped.Offset);
// If we found the inner if then we need to look for a new
// and a store within the if,
if (DoFindNew(branch.Index + 1, branch.Target.Index - branch.Index - 1))
{
m_foundSingle = true;
// and a second guard before the lock.
if (DoFindGuard(call.Index - 1))
{
m_foundGuard = true;
}
}
}
}
}
}
private bool DoIsEmptyString(Call call, int nth)
{
bool empty = false;
int index = m_info.Tracker.GetStackIndex(call.Index, nth);
if (index >= 0)
{
LoadString str = m_info.Instructions[index] as LoadString;
if (str != null)
{
empty = str.Value.Length == 0;
}
else
{
LoadStaticField field = m_info.Instructions[index] as LoadStaticField;
if (field != null)
{
empty = field.Field.DeclaringType.FullName == "System.String" && field.Field.Name == "Empty";
}
}
}
return(empty);
}
private TypeReference DoGetType(int index, int nth)
{
TypeReference type = null;
int i = m_info.Tracker.GetStackIndex(index, nth);
if (i >= 0)
{
do // TODO: would be nice to do something with load constant instructions as well
{
LoadArg arg = m_info.Instructions[i] as LoadArg;
if (arg != null && arg.Arg >= 1)
{
ParameterDefinition p = m_info.Method.Parameters[arg.Arg - 1];
type = p.ParameterType;
break;
}
LoadField field = m_info.Instructions[i] as LoadField;
if (field != null)
{
type = field.Field.FieldType;
break;
}
LoadLocal local = m_info.Instructions[i] as LoadLocal;
if (local != null)
{
VariableDefinition v = m_info.Method.Body.Variables[local.Variable];
type = v.VariableType;
break;
}
LoadStaticField sfield = m_info.Instructions[i] as LoadStaticField;
if (sfield != null)
{
type = sfield.Field.FieldType;
break;
}
Box box = m_info.Instructions[i] as Box;
if (box != null)
{
type = box.Type;
break;
}
}while (false);
}
return(type);
}
// match:
// ldsfld field
// ret
public void VisitRet(End end)
{
if (m_needsCheck && !m_foundRet && m_foundSingle)
{
if (end.Untyped.OpCode.Code == Code.Ret && end.Index > 1)
{
LoadStaticField load = m_info.Instructions[end.Index - 1] as LoadStaticField;
if (load != null && load.Field == m_field)
{
Log.DebugLine(this, "found return at {0:X2}", end.Untyped.Offset);
m_foundRet = true;
}
}
}
}
public void VisitCall(Call call)
{
if (m_fields.Count > 0 && !m_info.Method.IsConstructor && call.Target.HasThis)
{
int index = call.GetThisIndex(m_info);
if (index >= 0)
{
LoadStaticField load = m_info.Instructions[index] as LoadStaticField;
if (load != null && m_fields.IndexOf(load.Field) >= 0)
{
Entry entry = m_table[load.Field];
if (m_adders[entry.Key].IndexOf(call.Target.Name) >= 0)
{
if (!DoIsNullSet(call.Index, call.Target.Name))
{
if (!entry.FoundAdd)
{
Log.DebugLine(this, "found an add at {0:X2}", call.Untyped.Offset);
entry.FoundAdd = true;
}
}
else
{
if (!entry.FoundRemove)
{
Log.DebugLine(this, "found a null set at {0:X2}", call.Untyped.Offset);
entry.FoundRemove = true;
}
}
}
if (!entry.FoundRemove)
{
if (m_removers[entry.Key].IndexOf(call.Target.Name) >= 0)
{
Log.DebugLine(this, "found a remove at {0:X2}", call.Untyped.Offset);
entry.FoundRemove = true;
}
}
}
}
}
}
private TypeReference DoGetThisType(Call call)
{
TypeReference self = null;
if (call.Target.HasThis)
{
int index = call.GetThisIndex(m_info);
if (index >= 0)
{
do
{
LoadArg arg = m_info.Instructions[index] as LoadArg;
if (arg != null)
{
self = arg.Type;
break;
}
LoadField field = m_info.Instructions[index] as LoadField;
if (field != null)
{
self = field.Field.FieldType;
break;
}
LoadStaticField sfield = m_info.Instructions[index] as LoadStaticField;
if (sfield != null)
{
self = sfield.Field.FieldType;
break;
}
LoadLocal local = m_info.Instructions[index] as LoadLocal;
if (local != null)
{
self = local.Type;
break;
}
}while (false);
}
}
return(self);
}
public void VisitLoadStaticField(LoadStaticField load)
{
if (m_needsCheck)
{
State state;
if (m_fields.TryGetValue(load.Field, out state))
{
if (state == State.Defined)
{
m_fields[load.Field] = State.Used;
}
}
else
{
m_fields.Add(load.Field, State.Referenced);
}
}
}
// Find the following working backwards from index:
// ldsfld field
// brtrue 36
private bool DoFindGuard(int index)
{
while (index > 0)
{
ConditionalBranch branch = m_info.Instructions[index] as ConditionalBranch;
if (branch != null && (branch.Untyped.OpCode.Code == Code.Brtrue || branch.Untyped.OpCode.Code == Code.Brtrue_S))
{
LoadStaticField load = m_info.Instructions[index - 1] as LoadStaticField;
if (load != null && load.Field == m_field)
{
Log.DebugLine(this, "found the guard at {0:X2}", branch.Untyped.Offset);
return(true);
}
}
--index;
}
return(false);
}
private FieldReference DoSaveLocks(Call call)
{
FieldReference field = null;
// Look for a lock using one of our fields.
if (DoMatchLock1(call.Index))
{
LoadStaticField sload = (LoadStaticField)m_info.Instructions[call.Index - 3];
if (sload.Field.DeclaringType == m_info.Type)
{
field = sload.Field;
}
}
else if (DoMatchLock2(call.Index))
{
LoadField load = (LoadField)m_info.Instructions[call.Index - 3];
field = load.Field;
}
// If we found one then record that the method locked the field.
if (field != null)
{
List <FieldReference> fields;
if (!m_current.Locked.TryGetValue(m_info.Method, out fields))
{
fields = new List <FieldReference>();
m_current.Locked.Add(m_info.Method, fields);
}
fields.Add(field);
Log.DebugLine(this, "{0} locks {1}", m_info.Method.Name, field.Name);
}
return(field);
}
public void VisitSLoadField(LoadStaticField load)
{
DoAddField(load.Field);
}
public void VisitLoadStaticField(LoadStaticField field)
{
DoAdd(field.Field.FieldType);
}
public static bool IsIntOperand(MethodInfo info, int index, int nth)
{
bool isInt = false;
int i = info.Tracker.GetStackIndex(index, nth);
if (i >= 0)
{
do
{
LoadArg arg = info.Instructions[i] as LoadArg;
if (arg != null && arg.Arg >= 1)
{
ParameterDefinition p = info.Method.Parameters[arg.Arg - 1];
if (p.ParameterType.FullName == "System.Int32")
{
isInt = true;
}
break;
}
LoadConstantInt constant = info.Instructions[i] as LoadConstantInt;
if (constant != null)
{
Code code = constant.Untyped.OpCode.Code;
switch (code)
{
case Code.Ldc_I4_M1:
case Code.Ldc_I4_0:
case Code.Ldc_I4_1:
case Code.Ldc_I4_2:
case Code.Ldc_I4_3:
case Code.Ldc_I4_4:
case Code.Ldc_I4_5:
case Code.Ldc_I4_6:
case Code.Ldc_I4_7:
case Code.Ldc_I4_8:
case Code.Ldc_I4_S:
case Code.Ldc_I4:
isInt = true;
break;
}
break;
}
LoadField field = info.Instructions[i] as LoadField;
if (field != null)
{
if (field.Field.FieldType.FullName == "System.Int32")
{
isInt = true;
}
break;
}
LoadLocal local = info.Instructions[i] as LoadLocal;
if (local != null)
{
VariableDefinition v = info.Method.Body.Variables[local.Variable];
if (v.VariableType.FullName == "System.Int32")
{
isInt = true;
}
break;
}
LoadStaticField sfield = info.Instructions[i] as LoadStaticField;
if (sfield != null)
{
if (sfield.Field.FieldType.FullName == "System.Int32")
{
isInt = true;
}
break;
}
}while (false);
}
return(isInt);
}
private bool DoIsFloat(int index)
{
TypedInstruction instruction = m_info.Instructions[index];
TypeReference type = null;
do
{
LoadArg arg = instruction as LoadArg;
if (arg != null && arg.Arg >= 1)
{
type = m_info.Method.Parameters[arg.Arg - 1].ParameterType;
break;
}
LoadLocal local = instruction as LoadLocal;
if (local != null)
{
type = m_info.Method.Body.Variables[local.Variable].VariableType;
break;
}
LoadField field = instruction as LoadField;
if (field != null)
{
type = field.Field.FieldType;
break;
}
LoadStaticField sfield = instruction as LoadStaticField;
if (sfield != null)
{
type = sfield.Field.FieldType;
break;
}
LoadConstantFloat cf = instruction as LoadConstantFloat;
if (cf != null)
{
return(cf.Value != double.PositiveInfinity && cf.Value != double.NegativeInfinity);
}
BinaryOp binary = instruction as BinaryOp;
if (binary != null)
{
int j = m_info.Tracker.GetStackIndex(instruction.Index, 0);
int k = m_info.Tracker.GetStackIndex(instruction.Index, 1);
if (j >= 0 && k >= 0)
{
if (DoIsFloat(j) && DoIsFloat(k))
{
return(true);
}
}
}
if (instruction.Untyped.OpCode.Code == Code.Conv_R4 || instruction.Untyped.OpCode.Code == Code.Conv_R8 || instruction.Untyped.OpCode.Code == Code.Conv_R_Un)
{
return(true);
}
Call call = instruction as Call;
if (call != null)
{
type = call.Target.ReturnType.ReturnType;
break;
}
}while (false);
return(type != null && (type.FullName == "System.Single" || type.FullName == "System.Double"));
}
private bool DoIsBad(int index)
{
bool bad = false;
do
{
LoadArg arg = m_info.Instructions[index] as LoadArg;
if (arg != null && arg.Arg >= 1)
{
Log.DebugLine(this, "arg: {0}", arg.Arg);
ParameterDefinition p = m_info.Method.Parameters[arg.Arg - 1];
Log.DebugLine(this, "param {0} is of type {1}", arg.Arg, p.ParameterType.FullName);
if (DoIsBad(p.ParameterType))
{
bad = true;
}
break;
}
LoadLocal local = m_info.Instructions[index] as LoadLocal;
if (local != null)
{
Log.DebugLine(this, "local: {0}", local.Variable);
TypeReference type = m_info.Method.Body.Variables[local.Variable].VariableType;
Log.DebugLine(this, "local {0} is of type {1}", local.Variable, type.FullName);
if (DoIsBad(type))
{
bad = true;
}
break;
}
LoadField field = m_info.Instructions[index] as LoadField;
if (field != null)
{
Log.DebugLine(this, "field: {0}", field.Field.Name);
TypeReference type = field.Field.FieldType;
Log.DebugLine(this, "field {0} is of type {1}", field.Field.Name, type.FullName);
if (DoIsBad(type))
{
bad = true;
}
break;
}
LoadStaticField sfield = m_info.Instructions[index] as LoadStaticField;
if (sfield != null)
{
Log.DebugLine(this, "static field: {0}", sfield.Field.Name);
TypeReference type = sfield.Field.FieldType;
Log.DebugLine(this, "static field {0} is of type {1}", sfield.Field.Name, type.FullName);
if (DoIsBad(type))
{
bad = true;
}
break;
}
}while (false);
return(bad);
}
