mars.simulator
Class Simulator

java.lang.Object
  |
  +--mars.simulator.Simulator

public class Simulator

extends java.lang.Object

Used to simulate the execution of an assembled MIPS program.

Field Summary

static int	BREAKPOINT various reasons for simulate to end...
static int	EXCEPTION
static int	MAX_STEPS
static int	NORMAL_TERMINATION
static int	PAUSE_OR_STOP

Method Summary

static Simulator	getInstance() Returns the Simulator object
boolean	simulate(MIPSprogram p, int pc, int maxSteps, int[] breakPoints, javax.swing.AbstractAction actor) Simulate execution of given MIPS program.
void	stopExecution(javax.swing.AbstractAction actor) Set the volatile stop boolean variable checked by the execution thread at the end of each MIPS instruction execution.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

BREAKPOINT

public static final int BREAKPOINT

various reasons for simulate to end...

See Also:

Constant Field Values

EXCEPTION

public static final int EXCEPTION

See Also:

Constant Field Values

MAX_STEPS

public static final int MAX_STEPS

See Also:

Constant Field Values

NORMAL_TERMINATION

public static final int NORMAL_TERMINATION

See Also:

Constant Field Values

PAUSE_OR_STOP

public static final int PAUSE_OR_STOP

See Also:

Constant Field Values

Method Detail

getInstance

public static Simulator getInstance()

Returns the Simulator object

Returns:

the Simulator object in use

simulate

public boolean simulate(MIPSprogram p,
                        int pc,
                        int maxSteps,
                        int[] breakPoints,
                        javax.swing.AbstractAction actor)
                 throws ProcessingException

Simulate execution of given MIPS program. It must have already been assembled.

Parameters:

p - The MIPSprogram to be simulated.

pc - address of first instruction to simulate; this goes into program counter

maxSteps - maximum number of steps to perform before returning false (0 or less means no max)

breakPoints - array of breakpoint program counter values, use null if none

actor - the GUI component responsible for this call, usually GO or STEP. null if none.

Returns:

true if execution completed, false otherwise

Throws:

ProcessingException - Throws exception if run-time exception occurs.

stopExecution

public void stopExecution(javax.swing.AbstractAction actor)

Set the volatile stop boolean variable checked by the execution thread at the end of each MIPS instruction execution. If variable is found to be true, the execution thread will depart gracefully so the main thread handling the GUI can take over. This is used by both STOP and PAUSE features.