public MixInstruction GetInstruction(byte opcode, FieldSpec fieldSpec)
{
if (!mOpcodeInstructionMap.TryGetValue(opcode, out List <MixInstruction> instructions))
{
return(null);
}
int startIndex = 0;
MixInstruction defaultInstruction = null;
if (instructions[0].FieldSpec == null)
{
defaultInstruction = instructions[0];
startIndex = 1;
}
for (int index = startIndex; index < instructions.Count; index++)
{
if (instructions[index].FieldSpec == fieldSpec)
{
return(instructions[index]);
}
}
return(defaultInstruction);
}
MixByte GetFieldSpecValue(AssemblingStatus status, MixInstruction mixInstruction)
{
var fieldValue = mField.GetValue(status.LocationCounter);
switch (mixInstruction.MetaFieldSpec.Presence)
{
case MetaFieldSpec.Presences.Forbidden:
if (fieldValue == long.MinValue)
{
return(mixInstruction.FieldSpec.MixByteValue);
}
status.ReportParsingError(LineSection.AddressField, mFieldPartCharIndex, mTextLength - mFieldPartCharIndex, "fieldspec forbidden for this instruction");
return(null);
case MetaFieldSpec.Presences.Optional:
if (fieldValue == long.MinValue)
{
return(mixInstruction.MetaFieldSpec.DefaultFieldSpec.MixByteValue);
}
return((int)fieldValue);
case MetaFieldSpec.Presences.Mandatory:
if (fieldValue != long.MinValue)
{
return((int)fieldValue);
}
status.ReportParsingError(LineSection.AddressField, mFieldPartCharIndex, mTextLength - mFieldPartCharIndex, "fieldspec mandatory for this instruction");
return(null);
}
return(null);
}
void AddInstruction(string mnemonic, MixInstruction instruction)
{
mMnemonicInstructionMap.Add(mnemonic, instruction);
var list = mOpcodeInstructionMap.GetOrCreate(instruction.Opcode);
if (instruction.FieldSpec == null)
{
list.Insert(0, instruction);
}
else
{
list.Add(instruction);
}
}
