/// <summary>
/// Since we need to use ourselves.
/// </summary>
/// <param name="method"></param>
/// <param name="instruction"></param>
/// <param name="indentStart"></param>
/// <returns></returns>
public static string ParseInstruction(MethodDefinition method, Instruction instruction, int indentStart)
{
var opcode = instruction.OpCode;
string output = "";
//output += AssemblyHelper.Indent("// {0}: {1} {2}", indentStart, instruction.Offset, instruction.OpCode, instruction.Operand) + Environment.NewLine;
if (InstructionHelper.IsBranchConditional(opcode.Code))
{
output += Indent(GetIfStatement(method, instruction), indentStart) + Environment.NewLine;
output += ParseInstruction(method, instruction.Operand as Instruction, indentStart + 1);
}
// Check if the instruction is for
// storing a value onto a variable
if (InstructionHelper.IsStore(opcode.Code))
{
output += Indent(GetStoreLocation(method, instruction) + " = " + GetValueOf(method, instruction.Previous) + ";", indentStart) + Environment.NewLine;
}
// Check if we want to return the method
// And if there is any value we want to return.
else if (opcode.Code == Code.Ret)
{
if (InstructionHelper.IsLoad(instruction.Previous.OpCode.Code))
{
output += Indent("return " + GetValueOf(method, instruction.Previous) + ";", indentStart) + Environment.NewLine;
}
else
{
output += Indent("return;", indentStart) + Environment.NewLine;
}
}
return(output);
}
public static string GetIfStatement(MethodDefinition method, Instruction instruction)
{
var target = "";
var ifStatement = "if(";
var prev = instruction.Previous;
if (InstructionHelper.IsLoad(prev.OpCode.Code))
{
target = GetValueOf(method, prev);
}
if (InstructionHelper.IsBranchOnFalse(instruction.OpCode.Code))
{
ifStatement += "!";
}
return(ifStatement + target + ")");
}
public static string GetConditionalStatement(MethodDefinition method, Instruction instruction)
{
var code = instruction.OpCode.Code;
var val2 = instruction.Previous;
var val1 = val2.Previous;
if (InstructionHelper.IsEqualTo(code))
{
return(GetValueOf(method, val1) + " == " + GetValueOf(method, val2));
}
else if (InstructionHelper.IsLessThan(code))
{
return(GetValueOf(method, val1) + " < " + GetValueOf(method, val2));
}
else
{
return(GetValueOf(method, val1) + " > " + GetValueOf(method, val2));
// IsGreaterThan
}
}
/// <summary>
/// This function will return the name of the variable, argument, etc
/// that we want to store our value into.
/// </summary>
/// <param name="method"></param>
/// <param name="instruction"></param>
/// <returns></returns>
public static string GetStoreLocation(MethodDefinition method, Instruction instruction)
{
var code = instruction.OpCode.Code;
if (instruction.Operand != null && !InstructionHelper.IsStoreN(code))
{
return(instruction.Operand.ToString());
}
if (InstructionHelper.IsStoreLocalVariable(code))
{
if (InstructionHelper.IsStoreN(code))
{
/* Not yet implemented. */
}
else
{
var index = InstructionHelper.GetCodeIndex(code);
return(GetVariableName(method.Body.Variables[index]));
}
}
if (InstructionHelper.IsStoreArgument(code))
{
if (InstructionHelper.IsStoreN(code))
{
return(instruction.Operand.ToString());
}
else
{
var index = InstructionHelper.GetCodeIndex(code);
return(method.Parameters[index].Name);
}
}
return("");
}
/// <summary>
/// This function will return a string, representing the values grabbed from the instruction
/// </summary>
/// <param name="instruction"></param>
/// <returns></returns>
public static string GetValueOf(MethodDefinition method, Instruction instruction)
{
var code = instruction.OpCode.Code;
// If this is a conditional instruction. lets return the value of that.
if (InstructionHelper.IsConditional(instruction.OpCode.Code))
{
return(GetConditionalStatement(method, instruction));
}
// Check if we are trying to load a value
// Can be, Load a field, load a constant value, argument
// variable and more.
if (InstructionHelper.IsLoad(code))
{
// Check if we want to return a null value
if (InstructionHelper.IsLoadNull(instruction.OpCode.Code))
{
return("null");
}
// For now, we will settle with just handling integers.
// We will have to add more if checks later to support
// strings, variables, etc.
if (InstructionHelper.IsLoadInteger(code))
{
// In case the integer is bigger than 4
// We will need to get the value from the
// operand instead of the "index".
if (InstructionHelper.IsLoadN(code))
{
return(instruction.Operand.ToString());
}
else
{
// The GetCodeIndex will return the value used from
// the constant load. For instance ldc.i4.4 will return
// the value 4, ldc.i4.3 will return value 3. Etc.
return(InstructionHelper.GetCodeIndex(code).ToString());
}
}
// Check if we want to load a string
// if so, then return the value from the operand.
if (InstructionHelper.IsLoadString(code))
{
return("\"" + instruction.Operand + "\"");
}
// If we want to load a local variable.
// So be it!
if (InstructionHelper.IsLoadLocalVariable(code))
{
if (InstructionHelper.IsLoadN(code))
{
var targetVariable = instruction.Operand as VariableDefinition;
return(GetVariableName(targetVariable));
}
else
{
var index = InstructionHelper.GetCodeIndex(code);
return(GetVariableName(method.Body.Variables[index]));
}
}
// If we want to load the value of a argument
// Then this is necessary.
if (InstructionHelper.IsLoadArgs(code))
{
if (InstructionHelper.IsLoadN(code))
{
return(instruction.Operand.ToString());
}
else
{
var index = InstructionHelper.GetCodeIndex(code);
if (method.IsConstructor)
{
index--;
}
return(method.Parameters[index].Name);
}
}
}
// If our instructions are to call a method
if (InstructionHelper.IsCallMethod(code))
{
// We will need to grab the information of that specific method
// By casting the Operand into a MethodDefinition.
var callingMethod = instruction.Operand as MethodDefinition;
// Note: We are not managing any parameters yet.
return(callingMethod.Name + "()");
}
// Return a empty value if we can't determine what we want to return.
return("");
}