edu.gvsu.mipsunit.munit

Class MARSSimulator

java.lang.Object

edu.gvsu.mipsunit.munit.MARSSimulator

public class MARSSimulator
extends java.lang.Object

An interface to the MARS MIPS simulator.

Author:

Jack Rosenhauer II and Zachary Kurmas

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	MARSSimulator.DuplicateLabelException Exception raised when attempting to create a label when a label of the same name already exists.
static class	MARSSimulator.InvalidRegisterException Exception thrown if invalid register number is given.
static class	MARSSimulator.LabelNotFoundException Exception thrown if user specifies a label that does not exist
static class	MARSSimulator.LabelTypeException Exception raised when a label is of the wrong type.
static class	MARSSimulator.MUNITAddressErrorException Exception raised when requesting an invalid memory address.
static class	MARSSimulator.MUNITProcessingException Exception raised when the MARS simulator raises a ProcessingException while simulating assembly code.
static class	MARSSimulator.NullLabelException Exception raised when passing null as a label.
static class	MARSSimulator.SymbolType Identifies Symbol as a label in either the .text section or the .data section.

Constructor Summary

Constructors

Constructor and Description
MARSSimulator() Constructor.
MARSSimulator(boolean initializeGlobals) Constructor.

Method Summary

Modifier and Type	Method and Description
void	addData(java.lang.String toAdd) Add a line to the program's .data section
mars.ErrorList	assemble() Assemble the set of loaded assembly files.
int	get(int r_num) Returns the value of a register.
double	get(MUnit.DoubleRegister reg) Returns the value of a double register
float	get(MUnit.FloatRegister reg) Returns the value of a float register
byte[]	getBytes(int address, int num_bytes) Return the bytes at the specified memory locations.
byte[]	getBytes(java.lang.String label, int offset, int num_bytes) Return the bytes at the specified memory locations.
double[]	getDoubles(int address, int num_doubles) Return the doubles at the specified memory locations.
double[]	getDoubles(java.lang.String label, int offset, int num_doubles) Return the doubles at the specified memory locations.
float[]	getFloats(int address, int num_floats) Return the floats at the specified memory locations.
float[]	getFloats(java.lang.String label, int offset, int num_floats) Return the floats at the specified memory locations.
short[]	getHalfwords(int address, int num_halfwords) Return the halfwords at the specified memory locations.
short[]	getHalfwords(java.lang.String label, int offset, int num_halfwords) Return the halfwords at the specified memory locations.
mars.assembler.Symbol	getSymbolFromCurrentProgram(java.lang.String symbol) Get a Symbol for a label from the current program's symbol table.
int[]	getWords(int address, int num_words) Return the words at the specified memory locations
int[]	getWords(java.lang.String label, int offset, int num_words) Return the words at the specified memory locations
void	load(mars.MIPSprogram p) Add p to the list of programs under test.
void	load(java.lang.String filename) Adds a file to the the list of files to be loaded before execution (i.e., the set of assembly files under test).
boolean	noOtherMemoryModifications() Return true if all modified memory locations have been returned through a "get..." call.
boolean	noOtherNonStackModifications(int stackMax) Return true if all modified non-stack memory locations have been returned through a "get..." call.
boolean	noOtherStaticDataMemoryModifications() Return true if all modified static data memory locations have been returned through a "get..." call.
int	run(java.lang.String label) Run the function under test
void	set(int r_num, int value) Sets a register to the supplied value
void	set(int r_num, java.lang.String value, boolean verify) Sets a register to the supplied label.
void	set(MUnit.DoubleRegister reg, double value) Sets a double register to the supplied value
void	set(MUnit.FloatRegister reg, float value) Sets a float register to the supplied value
void	setAssemblyFiles(java.util.ArrayList<mars.MIPSprogram> assemblyFiles)
static MARSSimulator	singleton() Return the singleton MARSSimulator object

Methods inherited from class java.lang.Object

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

Constructor Detail

MARSSimulator

public MARSSimulator(boolean initializeGlobals)

Constructor. This constructor also initializes the singleton object and throws an exception if the singleton object has already been initialized.

Parameters:

initializeGlobals - true to call Mars's Globals.initialize() method.

Throws:

java.lang.IllegalStateException - if the singleton object has already been created.

MARSSimulator

public MARSSimulator()

Constructor. This constructor also initializes the singleton object and throws an exception if the singleton object has already been initialized.

Throws:

java.lang.IllegalStateException - if the singleton object has already been created.

Method Detail

setAssemblyFiles

public void setAssemblyFiles(java.util.ArrayList<mars.MIPSprogram> assemblyFiles)

singleton

public static MARSSimulator singleton()

Return the singleton MARSSimulator object

Returns:

the singleton MARSSimulator object

getSymbolFromCurrentProgram

public mars.assembler.Symbol getSymbolFromCurrentProgram(java.lang.String symbol)

Get a Symbol for a label from the current program's symbol table. This method is used after calls to run() (when labels are automatically generated and inserted into the current program.)

Parameters:

symbol - the symbol to get

Returns:

the Symbol, or {code null} if the label is not found (or if st is null).

load

public void load(java.lang.String filename)
          throws mars.ProcessingException

Adds a file to the the list of files to be loaded before execution (i.e., the set of assembly files under test).

Parameters:

filename - name of file to be loaded.

Throws:

mars.ProcessingException - if the file can't be tokenized.

load

public void load(mars.MIPSprogram p)

Add p to the list of programs under test. (This method is used to attach this object to the program currently being run in the MARS simulator.)

Parameters:

p - the MIPSprogram to add.

assemble

public mars.ErrorList assemble()
                        throws mars.ProcessingException

Assemble the set of loaded assembly files.

Returns:

the list of warningsreturned. (The returned list contains warnings only. Errors generate exceptions.)

Throws:

mars.ProcessingException - if the assembly code contains errors.

set

public void set(int r_num,
                int value)

Sets a register to the supplied value

Parameters:

r_num - Register to be set.

value - Integer value to set the register to.

set

public void set(int r_num,
                java.lang.String value,
                boolean verify)

Sets a register to the supplied label. Note: The String value can come from two places: It can be a label in the code under test, in which case verify should be true (to be sure it is in the symbol table). value can also come from a MUnit.Label, in which case verify should be false (The symbol behind the Label doesn't get added to the symbol table until run(java.lang.String) is called. Thus, the verification will fail.)

Parameters:

r_num - Register to be set.

value - Label to set the register to.

verify - verify that value appears in the symbol table.

set

public void set(MUnit.DoubleRegister reg,
                double value)

Sets a double register to the supplied value

Parameters:

reg - the double register to be set

value - the value

set

public void set(MUnit.FloatRegister reg,
                float value)

Sets a float register to the supplied value

Parameters:

reg - the float register to be set

value - the value

addData

public void addData(java.lang.String toAdd)

Add a line to the program's .data section

Parameters:

toAdd - The line to add.

get

public int get(int r_num)

Returns the value of a register.

Parameters:

r_num - The register to be returned.

Returns:

The value of the register.

get

public double get(MUnit.DoubleRegister reg)

Returns the value of a double register

Parameters:

reg - the register

Returns:

the value in the register

get

public float get(MUnit.FloatRegister reg)

Returns the value of a float register

Parameters:

reg - the register

Returns:

the value in the register

getWords

public int[] getWords(int address,
                      int num_words)
               throws MARSSimulator.MUNITAddressErrorException

Return the words at the specified memory locations

Parameters:

address - the base address of the words to load

num_words - number of words to return

Returns:

the words at the specified locations

Throws:

MARSSimulator.MUNITAddressErrorException - if the address isn't valid.

MARSSimulator.LabelNotFoundException - if label isn't found.

getWords

public int[] getWords(java.lang.String label,
                      int offset,
                      int num_words)
               throws MARSSimulator.MUNITAddressErrorException

Return the words at the specified memory locations

Parameters:

label - data label in memory

offset - byte offset to the data label

num_words - number of words to return

Returns:

the words at the specified locations

Throws:

MARSSimulator.MUNITAddressErrorException - if the address isn't valid.

MARSSimulator.LabelNotFoundException - if label isn't found.

getHalfwords

public short[] getHalfwords(java.lang.String label,
                            int offset,
                            int num_halfwords)

Return the halfwords at the specified memory locations.

Parameters:

label - data label in memory

offset - byte offset to the data label

num_halfwords - number of bytes to return

Returns:

the halfwords at the specified locations

Throws:

MARSSimulator.MUNITAddressErrorException - if the address isn't valid.

MARSSimulator.LabelNotFoundException - if label isn't found.

getHalfwords

public short[] getHalfwords(int address,
                            int num_halfwords)

Return the halfwords at the specified memory locations.

Parameters:

address - the address of the data

num_halfwords - number of bytes to return

Returns:

the halfwords at the specified locations

Throws:

MARSSimulator.MUNITAddressErrorException - if the address isn't valid.

getBytes

public byte[] getBytes(java.lang.String label,
                       int offset,
                       int num_bytes)

Return the bytes at the specified memory locations.

Parameters:

label - data label in memory

offset - byte offset to the data label

num_bytes - number of halfwords to return

Returns:

the bytes at the specified locations

Throws:

MARSSimulator.MUNITAddressErrorException - if the address isn't valid.

MARSSimulator.LabelNotFoundException - if label isn't found.

getBytes

public byte[] getBytes(int address,
                       int num_bytes)

Return the bytes at the specified memory locations.

Parameters:

address - the address of the desired data

num_bytes - number of halfwords to return

Returns:

the bytes at the specified locations

Throws:

MARSSimulator.MUNITAddressErrorException - if the address isn't valid.

MARSSimulator.LabelNotFoundException - if label isn't found.

getDoubles

public double[] getDoubles(java.lang.String label,
                           int offset,
                           int num_doubles)

Return the doubles at the specified memory locations.

Parameters:

label - data label in memory

offset - byte offset to the data label

num_doubles - number of doubles to return

Returns:

the bytes at the specified locations

Throws:

MARSSimulator.MUNITAddressErrorException - if the address isn't valid.

MARSSimulator.LabelNotFoundException - if label isn't found.

getDoubles

public double[] getDoubles(int address,
                           int num_doubles)

Return the doubles at the specified memory locations.

Parameters:

address - the address of the desired data

num_doubles - number of doubles to return

Returns:

the bytes at the specified locations

Throws:

MARSSimulator.MUNITAddressErrorException - if the address isn't valid.

MARSSimulator.LabelNotFoundException - if label isn't found.

getFloats

public float[] getFloats(java.lang.String label,
                         int offset,
                         int num_floats)

Return the floats at the specified memory locations.

Parameters:

label - data label in memory

offset - byte offset to the data label

num_floats - number of floats to return

Returns:

the bytes at the specified locations

Throws:

MARSSimulator.MUNITAddressErrorException - if the address isn't valid.

MARSSimulator.LabelNotFoundException - if label isn't found.

getFloats

public float[] getFloats(int address,
                         int num_floats)

Return the floats at the specified memory locations.

Parameters:

address - the address of the desired data

num_floats - number of floats to return

Returns:

the bytes at the specified locations

Throws:

MARSSimulator.MUNITAddressErrorException - if the address isn't valid.

noOtherMemoryModifications

public boolean noOtherMemoryModifications()

Return true if all modified memory locations have been returned through a "get..." call. (In other words, return true if the test writer has inspected all the memory values that have changed.)

Returns:

true if all modified memory locations have been returned through a "get..." call.

noOtherStaticDataMemoryModifications

public boolean noOtherStaticDataMemoryModifications()

Return true if all modified static data memory locations have been returned through a "get..." call. (In other words, return true if the test writer has inspected all the static data memory values that have changed.) The "static data" memory area typically runs from 0x1000_0000 through 0x1000_40000. The heap typically begins at 0x1004_0000. This method does not verify whether heap changes or stack changes have been inspected.

Returns:

true if all modified static data memory locations have been returned through a "get..." call.

noOtherNonStackModifications

public boolean noOtherNonStackModifications(int stackMax)

Return true if all modified non-stack memory locations have been returned through a "get..." call. (In other words, return true if the test writer has inspected all the memory values that have changed -- except for those on the stack.) For purposes of this check, the stack is assumed to be at most stackMax bytes. Thus,

1. data at or below 0x0x7fff_effc - stackMax is checked. (0x0x7fff_effc is the default starting value of the stack.)
2. An error will be reported if the code under test puts more than stackMax bytes on the stack.

Parameters:

stackMax - the assumed maximum size of the stack.

Returns:

true if all modified non-stack memory locations have been returned through a "get..." call.

run

public int run(java.lang.String label)

Run the function under test

Parameters:

label - the function under test

Returns:

the value in register ($v0) at the end of the simulation