void IEmitter.Emit(ILGenerator methodIL, CpuInternalBuilders internals)
{
methodIL.Emit(OpCodes.Ldarg_0);
switch (_opcode)
{
case 0x06: // MVI B
methodIL.EmitLd8Immediate(_operand1);
methodIL.Emit(OpCodes.Stfld, internals.B);
break;
case 0x0E: // MVI C
methodIL.EmitLd8Immediate(_operand1);
methodIL.Emit(OpCodes.Stfld, internals.C);
break;
case 0x16: // MVI D
methodIL.EmitLd8Immediate(_operand1);
methodIL.Emit(OpCodes.Stfld, internals.D);
break;
case 0x1E: // MVI E
methodIL.EmitLd8Immediate(_operand1);
methodIL.Emit(OpCodes.Stfld, internals.E);
break;
case 0x26: // MVI H
methodIL.EmitLd8Immediate(_operand1);
methodIL.Emit(OpCodes.Stfld, internals.H);
break;
case 0x2E: // MVI L
methodIL.EmitLd8Immediate(_operand1);
methodIL.Emit(OpCodes.Stfld, internals.L);
break;
case 0x36: // MVI M
methodIL.Emit(OpCodes.Ldfld, internals.MemoryBusField);
methodIL.EmitLd8Immediate(_operand1);
methodIL.Emit(OpCodes.Ldarg_0);
methodIL.Emit(OpCodes.Call, internals.HL);
methodIL.Emit(OpCodes.Callvirt, internals.MemoryBusField.FieldType.GetMethod("WriteByte") !);
break;
case 0x3E: // MVI A
methodIL.EmitLd8Immediate(_operand1);
methodIL.Emit(OpCodes.Stfld, internals.A);
break;
default:
throw new ArgumentOutOfRangeException(nameof(_opcode),
$"MVI shouldn't be run for opcode byte {_opcode}");
}
}
public void PostInstructionEmit(ILGenerator methodIL, CpuInternalBuilders internals, ushort programCounter)
{
// Check whether to fire half screen interrupt
var skipInterrupt = methodIL.DefineLabel();
var skipHalfScreen = methodIL.DefineLabel();
// Always decrement cycles to interrupt
methodIL.Emit(OpCodes.Ldloc, _interruptDownCounter.LocalIndex);
methodIL.Emit(OpCodes.Stloc, _oldInterruptDownCounter.LocalIndex);
methodIL.Emit(OpCodes.Ldloc, _interruptDownCounter.LocalIndex);
methodIL.Emit(OpCodes.Ldarg_0);
methodIL.Emit(OpCodes.Ldfld, internals.CycleCounter);
methodIL.Emit(OpCodes.Sub);
methodIL.Emit(OpCodes.Stloc, _interruptDownCounter.LocalIndex);
// Check if we've just crossed the half screen boundary
methodIL.Emit(OpCodes.Ldloc, _interruptDownCounter.LocalIndex);
methodIL.Emit(OpCodes.Ldc_I8, SpaceInvadersApplication.HalfCyclesPerScreen + 1);
methodIL.Emit(OpCodes.Clt);
methodIL.Emit(OpCodes.Ldloc, _oldInterruptDownCounter.LocalIndex);
methodIL.Emit(OpCodes.Ldc_I8, SpaceInvadersApplication.HalfCyclesPerScreen);
methodIL.Emit(OpCodes.Cgt);
methodIL.Emit(OpCodes.And);
methodIL.Emit(OpCodes.Brfalse, skipHalfScreen);
#if DEBUG
methodIL.EmitWriteLine("Half screen interrupt");
#endif
// Actually _do_ the half screen interrupt (RST 0)
// If IE flag set then skip interrupt check
methodIL.Emit(OpCodes.Ldarg_0);
methodIL.Emit(OpCodes.Ldfld, internals.InterruptEnable);
methodIL.Emit(OpCodes.Brfalse, skipInterrupt);
#if DEBUG
methodIL.EmitWriteLine("Half screen interrupt EI enabled");
#endif
var halfEmitter = new CallEmitter(0xCF, programCounter, internals.ProgramLabels[0x08], 0x08);
halfEmitter.Emit(methodIL, internals);
methodIL.Emit(OpCodes.Br, skipInterrupt);
// Skipped the half screen so now check for full screen interrupt
methodIL.MarkLabel(skipHalfScreen);
methodIL.Emit(OpCodes.Ldc_I8, 0L);
methodIL.Emit(OpCodes.Ldloc, _interruptDownCounter);
methodIL.Emit(OpCodes.Blt, skipInterrupt);
#if DEBUG
methodIL.EmitWriteLine("Full screen interrupt");
#endif
// Fire the vblank routine on the renderer
methodIL.Emit(OpCodes.Ldarg_0);
methodIL.Emit(OpCodes.Ldfld, internals.MemoryBusField);
methodIL.Emit(OpCodes.Callvirt, internals.RendererField.FieldType.GetMethod("VBlank") !);
// Reset the interrupt down counter
methodIL.Emit(OpCodes.Ldc_I8, SpaceInvadersApplication.CyclesPerScreen);
methodIL.Emit(OpCodes.Stloc, _interruptDownCounter.LocalIndex);
// Fire the vblank interrupt routine
// If IE flag not set then skip interrupt fire (but still do vblank call)
methodIL.Emit(OpCodes.Ldarg_0);
methodIL.Emit(OpCodes.Ldfld, internals.InterruptEnable);
methodIL.Emit(OpCodes.Brfalse, skipInterrupt);
var fullEmitter = new CallEmitter(0xD7, programCounter, internals.ProgramLabels[0x10], 0x10);
fullEmitter.Emit(methodIL, internals);
methodIL.MarkLabel(skipInterrupt);
}
public void PostInstructionEmit(ILGenerator methodIL, CpuInternalBuilders internals, ushort programCounter)
{
}
