ChangeBlockF99b.java

/*
  ChangeBlockF99b.java

  (c) 2014-2015 Edward Swartz

  All rights reserved. This program and the accompanying materials
  are made available under the terms of the Eclipse Public License v1.0
  which accompanies this distribution, and is available at
  http://www.eclipse.org/legal/epl-v10.html
 */
package v9t9.machine.f99b.asm;

import v9t9.common.cpu.ChangeBlock;
import v9t9.common.cpu.IChangeElement;
import v9t9.common.cpu.ICpu;
import v9t9.common.cpu.ICpuState;
import v9t9.machine.f99b.cpu.CpuF99b;
import v9t9.machine.f99b.cpu.CpuStateF99b;
import v9t9.machine.f99b.cpu.F99bInstructionFactory;

/**
 * @author ejs
 *
 */
public class ChangeBlockF99b extends ChangeBlock {
	public CpuStateF99b cpu;
	
	public short[] inStack;
	public short[] inReturnStack;
	public int fetchCycles;
	public PreExecute preExecute;
	
	public class PreExecute implements IChangeElement {

		public short pc;
		public int cycles;
		public short st;
		public int sp;
		public int rp;
		public int up;
		public int lp;

		/* (non-Javadoc)
		 * @see v9t9.common.cpu.IChangeElement#apply(v9t9.common.cpu.ICpuState)
		 */
		@Override
		public void apply(ICpuState cpuState) {
			pc = cpu.getPC();
			
			cycles = cpu.getCycleCounts().getTotal();
			st = cpu.getST();
			
			sp = cpuState.getRegister(CpuF99b.SP);
			rp = cpuState.getRegister(CpuF99b.RP);
			up = cpuState.getRegister(CpuF99b.UP);
			lp = cpuState.getRegister(CpuF99b.LP);
		}

		/* (non-Javadoc)
		 * @see v9t9.common.cpu.IChangeElement#revert(v9t9.common.cpu.ICpuState)
		 */
		@Override
		public void revert(ICpuState cpuState) {
			cpuState.setRegister(CpuF99b.SP, sp);
			cpuState.setRegister(CpuF99b.RP, rp);
			cpuState.setRegister(CpuF99b.UP, up);
			cpuState.setRegister(CpuF99b.LP, lp);
			
		}
		
	}
	public ChangeBlockF99b(ICpu cpu) {
		this(cpu, cpu.getState().getPC());
	}
	public ChangeBlockF99b(ICpu cpu, int pc) {
		this.cpu = (CpuStateF99b) cpu.getState();
		
		cpu.getCycleCounts().saveState();
		int total = cpu.getCycleCounts().getTotal();
		inst = (InstructionF99b) F99bInstructionFactory.INSTANCE.decodeInstruction(pc, cpu.getConsole());
		fetchCycles = cpu.getCycleCounts().getTotal() - total;
		cpu.getCycleCounts().restoreState();
		
		preExecute = new PreExecute();
		push(preExecute);
		
	}
	
	@Override
	public int getPC() {
		return inst.pc;
	}
	/**
	 * @return
	 */
	public int getSize() {
		return inst.getSize();
	}

}