public void Scan(MethodBody methodBody)
{
MethodDefinition thisMethod = methodBody.Method;
Dictionary <VariableDefinition, ValueBasicBlockPair> locals = new Dictionary <VariableDefinition, ValueBasicBlockPair> (methodBody.Variables.Count);
Dictionary <int, Stack <StackSlot> > knownStacks = new Dictionary <int, Stack <StackSlot> > ();
Stack <StackSlot> currentStack = new Stack <StackSlot> (methodBody.MaxStackSize);
ScanExceptionInformation(knownStacks, methodBody);
BasicBlockIterator blockIterator = new BasicBlockIterator(methodBody);
MethodReturnValue = null;
foreach (Instruction operation in methodBody.Instructions)
{
int curBasicBlock = blockIterator.MoveNext(operation);
if (knownStacks.ContainsKey(operation.Offset))
{
if (currentStack == null)
{
// The stack copy constructor reverses the stack
currentStack = new Stack <StackSlot> (knownStacks[operation.Offset].Reverse());
}
else
{
currentStack = MergeStack(currentStack, knownStacks[operation.Offset]);
}
}
if (currentStack == null)
{
currentStack = new Stack <StackSlot> (methodBody.MaxStackSize);
}
switch (operation.OpCode.Code)
{
case Code.Add:
case Code.Add_Ovf:
case Code.Add_Ovf_Un:
case Code.And:
case Code.Div:
case Code.Div_Un:
case Code.Mul:
case Code.Mul_Ovf:
case Code.Mul_Ovf_Un:
case Code.Or:
case Code.Rem:
case Code.Rem_Un:
case Code.Sub:
case Code.Sub_Ovf:
case Code.Sub_Ovf_Un:
case Code.Xor:
case Code.Cgt:
case Code.Cgt_Un:
case Code.Clt:
case Code.Clt_Un:
case Code.Shl:
case Code.Shr:
case Code.Shr_Un:
case Code.Ceq:
PopUnknown(currentStack, 2, methodBody, operation.Offset);
PushUnknown(currentStack);
break;
case Code.Dup:
currentStack.Push(currentStack.Peek());
break;
case Code.Ldnull:
currentStack.Push(new StackSlot(NullValue.Instance));
break;
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: {
int value = operation.OpCode.Code - Code.Ldc_I4_0;
ConstIntValue civ = new ConstIntValue(value);
StackSlot slot = new StackSlot(civ);
currentStack.Push(slot);
}
break;
case Code.Ldc_I4_M1: {
ConstIntValue civ = new ConstIntValue(-1);
StackSlot slot = new StackSlot(civ);
currentStack.Push(slot);
}
break;
case Code.Ldc_I4: {
int value = (int)operation.Operand;
ConstIntValue civ = new ConstIntValue(value);
StackSlot slot = new StackSlot(civ);
currentStack.Push(slot);
}
break;
case Code.Ldc_I4_S: {
int value = (sbyte)operation.Operand;
ConstIntValue civ = new ConstIntValue(value);
StackSlot slot = new StackSlot(civ);
currentStack.Push(slot);
}
break;
case Code.Arglist:
case Code.Ldftn:
case Code.Sizeof:
case Code.Ldc_I8:
case Code.Ldc_R4:
case Code.Ldc_R8:
PushUnknown(currentStack);
break;
case Code.Ldarg:
case Code.Ldarg_0:
case Code.Ldarg_1:
case Code.Ldarg_2:
case Code.Ldarg_3:
case Code.Ldarg_S:
case Code.Ldarga:
case Code.Ldarga_S:
ScanLdarg(operation, currentStack, thisMethod, methodBody);
break;
case Code.Ldloc:
case Code.Ldloc_0:
case Code.Ldloc_1:
case Code.Ldloc_2:
case Code.Ldloc_3:
case Code.Ldloc_S:
case Code.Ldloca:
case Code.Ldloca_S:
ScanLdloc(operation, currentStack, methodBody, locals);
break;
case Code.Ldstr: {
StackSlot slot = new StackSlot(new KnownStringValue((string)operation.Operand));
currentStack.Push(slot);
}
break;
case Code.Ldtoken:
ScanLdtoken(operation, currentStack);
break;
case Code.Ldind_I:
case Code.Ldind_I1:
case Code.Ldind_I2:
case Code.Ldind_I4:
case Code.Ldind_I8:
case Code.Ldind_R4:
case Code.Ldind_R8:
case Code.Ldind_U1:
case Code.Ldind_U2:
case Code.Ldind_U4:
case Code.Ldlen:
case Code.Ldvirtftn:
case Code.Localloc:
case Code.Refanytype:
case Code.Refanyval:
case Code.Conv_I1:
case Code.Conv_I2:
case Code.Conv_I4:
case Code.Conv_Ovf_I1:
case Code.Conv_Ovf_I1_Un:
case Code.Conv_Ovf_I2:
case Code.Conv_Ovf_I2_Un:
case Code.Conv_Ovf_I4:
case Code.Conv_Ovf_I4_Un:
case Code.Conv_Ovf_U:
case Code.Conv_Ovf_U_Un:
case Code.Conv_Ovf_U1:
case Code.Conv_Ovf_U1_Un:
case Code.Conv_Ovf_U2:
case Code.Conv_Ovf_U2_Un:
case Code.Conv_Ovf_U4:
case Code.Conv_Ovf_U4_Un:
case Code.Conv_U1:
case Code.Conv_U2:
case Code.Conv_U4:
case Code.Conv_I8:
case Code.Conv_Ovf_I8:
case Code.Conv_Ovf_I8_Un:
case Code.Conv_Ovf_U8:
case Code.Conv_Ovf_U8_Un:
case Code.Conv_U8:
case Code.Conv_I:
case Code.Conv_Ovf_I:
case Code.Conv_Ovf_I_Un:
case Code.Conv_U:
case Code.Conv_R_Un:
case Code.Conv_R4:
case Code.Conv_R8:
case Code.Ldind_Ref:
case Code.Ldobj:
case Code.Mkrefany:
case Code.Unbox:
case Code.Unbox_Any:
case Code.Box:
case Code.Neg:
case Code.Not:
PopUnknown(currentStack, 1, methodBody, operation.Offset);
PushUnknown(currentStack);
break;
case Code.Isinst:
case Code.Castclass:
// We can consider a NOP because the value doesn't change.
// It might change to NULL, but for the purposes of dataflow analysis
// it doesn't hurt much.
break;
case Code.Ldfld:
case Code.Ldsfld:
case Code.Ldflda:
case Code.Ldsflda:
ScanLdfld(operation, currentStack, thisMethod, methodBody);
break;
case Code.Newarr: {
StackSlot count = PopUnknown(currentStack, 1, methodBody, operation.Offset);
currentStack.Push(new StackSlot(new ArrayValue(count.Value, (TypeReference)operation.Operand)));
}
break;
case Code.Stelem_I:
case Code.Stelem_I1:
case Code.Stelem_I2:
case Code.Stelem_I4:
case Code.Stelem_I8:
case Code.Stelem_R4:
case Code.Stelem_R8:
case Code.Stelem_Any:
case Code.Stelem_Ref:
ScanStelem(operation, currentStack, methodBody, curBasicBlock);
break;
case Code.Ldelem_I:
case Code.Ldelem_I1:
case Code.Ldelem_I2:
case Code.Ldelem_I4:
case Code.Ldelem_I8:
case Code.Ldelem_R4:
case Code.Ldelem_R8:
case Code.Ldelem_U1:
case Code.Ldelem_U2:
case Code.Ldelem_U4:
case Code.Ldelem_Any:
case Code.Ldelem_Ref:
case Code.Ldelema:
ScanLdelem(operation, currentStack, methodBody, curBasicBlock);
break;
case Code.Cpblk:
case Code.Initblk:
PopUnknown(currentStack, 3, methodBody, operation.Offset);
break;
case Code.Stfld:
case Code.Stsfld:
ScanStfld(operation, currentStack, thisMethod, methodBody);
break;
case Code.Cpobj:
PopUnknown(currentStack, 2, methodBody, operation.Offset);
break;
case Code.Stind_I:
case Code.Stind_I1:
case Code.Stind_I2:
case Code.Stind_I4:
case Code.Stind_I8:
case Code.Stind_R4:
case Code.Stind_R8:
case Code.Stind_Ref:
case Code.Stobj:
ScanIndirectStore(operation, currentStack, methodBody);
break;
case Code.Initobj:
case Code.Pop:
PopUnknown(currentStack, 1, methodBody, operation.Offset);
break;
case Code.Starg:
case Code.Starg_S:
ScanStarg(operation, currentStack, thisMethod, methodBody);
break;
case Code.Stloc:
case Code.Stloc_S:
case Code.Stloc_0:
case Code.Stloc_1:
case Code.Stloc_2:
case Code.Stloc_3:
ScanStloc(operation, currentStack, methodBody, locals, curBasicBlock);
break;
case Code.Constrained:
case Code.No:
case Code.Readonly:
case Code.Tail:
case Code.Unaligned:
case Code.Volatile:
break;
case Code.Brfalse:
case Code.Brfalse_S:
case Code.Brtrue:
case Code.Brtrue_S:
PopUnknown(currentStack, 1, methodBody, operation.Offset);
NewKnownStack(knownStacks, ((Instruction)operation.Operand).Offset, currentStack);
break;
case Code.Calli: {
var signature = (CallSite)operation.Operand;
if (signature.HasThis && !signature.ExplicitThis)
{
PopUnknown(currentStack, 1, methodBody, operation.Offset);
}
// Pop arguments
PopUnknown(currentStack, signature.Parameters.Count, methodBody, operation.Offset);
// Pop function pointer
PopUnknown(currentStack, 1, methodBody, operation.Offset);
// Push return value
if (signature.ReturnType.MetadataType != MetadataType.Void)
{
PushUnknown(currentStack);
}
}
break;
case Code.Call:
case Code.Callvirt:
case Code.Newobj:
HandleCall(methodBody, operation, currentStack, curBasicBlock);
break;
case Code.Jmp:
// Not generated by mainstream compilers
break;
case Code.Br:
case Code.Br_S:
NewKnownStack(knownStacks, ((Instruction)operation.Operand).Offset, currentStack);
ClearStack(ref currentStack);
break;
case Code.Leave:
case Code.Leave_S:
ClearStack(ref currentStack);
NewKnownStack(knownStacks, ((Instruction)operation.Operand).Offset, new Stack <StackSlot> (methodBody.MaxStackSize));
break;
case Code.Endfilter:
case Code.Endfinally:
case Code.Rethrow:
case Code.Throw:
ClearStack(ref currentStack);
break;
case Code.Ret: {
bool hasReturnValue = methodBody.Method.ReturnType.MetadataType != MetadataType.Void;
if (currentStack.Count != (hasReturnValue ? 1 : 0))
{
WarnAboutInvalidILInMethod(methodBody, operation.Offset);
}
if (hasReturnValue)
{
StackSlot retValue = PopUnknown(currentStack, 1, methodBody, operation.Offset);
MethodReturnValue = MergePointValue.MergeValues(MethodReturnValue, retValue.Value);
}
ClearStack(ref currentStack);
break;
}
case Code.Switch: {
PopUnknown(currentStack, 1, methodBody, operation.Offset);
Instruction[] targets = (Instruction[])operation.Operand;
foreach (Instruction target in targets)
{
NewKnownStack(knownStacks, target.Offset, currentStack);
}
break;
}
case Code.Beq:
case Code.Beq_S:
case Code.Bne_Un:
case Code.Bne_Un_S:
case Code.Bge:
case Code.Bge_S:
case Code.Bge_Un:
case Code.Bge_Un_S:
case Code.Bgt:
case Code.Bgt_S:
case Code.Bgt_Un:
case Code.Bgt_Un_S:
case Code.Ble:
case Code.Ble_S:
case Code.Ble_Un:
case Code.Ble_Un_S:
case Code.Blt:
case Code.Blt_S:
case Code.Blt_Un:
case Code.Blt_Un_S:
PopUnknown(currentStack, 2, methodBody, operation.Offset);
NewKnownStack(knownStacks, ((Instruction)operation.Operand).Offset, currentStack);
break;
}
}
}
public void Scan(MethodIL methodBody)
{
MethodDesc thisMethod = methodBody.OwningMethod;
ValueBasicBlockPair[] locals = new ValueBasicBlockPair[methodBody.GetLocals().Length];
Dictionary <int, Stack <StackSlot> > knownStacks = new Dictionary <int, Stack <StackSlot> >();
Stack <StackSlot> currentStack = new Stack <StackSlot>(methodBody.MaxStack);
ScanExceptionInformation(knownStacks, methodBody);
BasicBlockIterator blockIterator = new BasicBlockIterator(methodBody);
MethodReturnValue = null;
ILReader reader = new ILReader(methodBody.GetILBytes());
while (reader.HasNext)
{
int curBasicBlock = blockIterator.MoveNext(reader.Offset);
if (knownStacks.ContainsKey(reader.Offset))
{
if (currentStack == null)
{
// The stack copy constructor reverses the stack
currentStack = new Stack <StackSlot>(knownStacks[reader.Offset].Reverse());
}
else
{
currentStack = MergeStack(currentStack, knownStacks[reader.Offset]);
}
}
if (currentStack == null)
{
currentStack = new Stack <StackSlot>(methodBody.MaxStack);
}
int offset = reader.Offset;
ILOpcode opcode = reader.ReadILOpcode();
switch (opcode)
{
case ILOpcode.add:
case ILOpcode.add_ovf:
case ILOpcode.add_ovf_un:
case ILOpcode.and:
case ILOpcode.div:
case ILOpcode.div_un:
case ILOpcode.mul:
case ILOpcode.mul_ovf:
case ILOpcode.mul_ovf_un:
case ILOpcode.or:
case ILOpcode.rem:
case ILOpcode.rem_un:
case ILOpcode.sub:
case ILOpcode.sub_ovf:
case ILOpcode.sub_ovf_un:
case ILOpcode.xor:
case ILOpcode.cgt:
case ILOpcode.cgt_un:
case ILOpcode.clt:
case ILOpcode.clt_un:
case ILOpcode.shl:
case ILOpcode.shr:
case ILOpcode.shr_un:
case ILOpcode.ceq:
PopUnknown(currentStack, 2, methodBody, offset);
PushUnknown(currentStack);
reader.Skip(opcode);
break;
case ILOpcode.dup:
currentStack.Push(currentStack.Peek());
break;
case ILOpcode.ldnull:
currentStack.Push(new StackSlot(NullValue.Instance));
break;
case ILOpcode.ldc_i4_0:
case ILOpcode.ldc_i4_1:
case ILOpcode.ldc_i4_2:
case ILOpcode.ldc_i4_3:
case ILOpcode.ldc_i4_4:
case ILOpcode.ldc_i4_5:
case ILOpcode.ldc_i4_6:
case ILOpcode.ldc_i4_7:
case ILOpcode.ldc_i4_8:
{
int value = opcode - ILOpcode.ldc_i4_0;
ConstIntValue civ = new ConstIntValue(value);
StackSlot slot = new StackSlot(civ);
currentStack.Push(slot);
}
break;
case ILOpcode.ldc_i4_m1:
{
ConstIntValue civ = new ConstIntValue(-1);
StackSlot slot = new StackSlot(civ);
currentStack.Push(slot);
}
break;
case ILOpcode.ldc_i4:
{
int value = (int)reader.ReadILUInt32();
ConstIntValue civ = new ConstIntValue(value);
StackSlot slot = new StackSlot(civ);
currentStack.Push(slot);
}
break;
case ILOpcode.ldc_i4_s:
{
int value = (sbyte)reader.ReadILByte();
ConstIntValue civ = new ConstIntValue(value);
StackSlot slot = new StackSlot(civ);
currentStack.Push(slot);
}
break;
case ILOpcode.arglist:
case ILOpcode.ldftn:
case ILOpcode.sizeof_:
case ILOpcode.ldc_i8:
case ILOpcode.ldc_r4:
case ILOpcode.ldc_r8:
PushUnknown(currentStack);
reader.Skip(opcode);
break;
case ILOpcode.ldarg:
case ILOpcode.ldarg_0:
case ILOpcode.ldarg_1:
case ILOpcode.ldarg_2:
case ILOpcode.ldarg_3:
case ILOpcode.ldarg_s:
case ILOpcode.ldarga:
case ILOpcode.ldarga_s:
ScanLdarg(opcode, opcode switch
{
ILOpcode.ldarg => reader.ReadILUInt16(),
ILOpcode.ldarga => reader.ReadILUInt16(),
ILOpcode.ldarg_s => reader.ReadILByte(),
ILOpcode.ldarga_s => reader.ReadILByte(),
_ => opcode - ILOpcode.ldarg_0
}, currentStack, thisMethod);
break;
