uk.ac.man.cs.rainbow.simulator
Class RASMCode

java.lang.Object
  |
  +--uk.ac.man.cs.rainbow.simulator.RASMCode

All Implemented Interfaces:

Serializable

public class RASMCode

extends Object

implements Serializable

A block of RASM code. This is the primary mechanism for definining the behaviour of a thread for simulation in the Rainbow simulator.

See Also:

RASMThread, Instruction, Serialized Form

Inner Class Summary

static class	RASMCode.Exception Exceptions thrown due to bad assembly code.
static class	RASMCode.Label A label/location in a block of code.

Field Summary

static String	ARG_PREFIX Argument references are preceded by this string.
static char	COMMENT_STARTER Indicates that this line of RASM text is a comment.
static String	CONSTANT_COMMAND A constant command starts with this opcode.
static String	LABEL_PREFIX Label references are preceded by this string.
static char	LABEL_STARTER Indicates that this line of RASM text is a label definition.
static String	MODULE_COMMAND A module command starts with this opcode.
static String	MODULE_SEPARATOR The module/label string separator.
static String	PUSH_COMMAND A push command starts with this opcode.
static String	RASM_EXTENSION The extension for a RASM file.
static String	STDLIB_PROPERTY_NAME The name of the property to read the standard library from.
static String	STRING_PREFIX String references are preceded by this string.
static String	TYPE_COMMAND A type command starts with this opcode.
static String	TYPE_PREFIX Type references are preceded by this string.

Constructor Summary

RASMCode(Hashtable library, BufferedReader contents)
Create a new block of code.

RASMCode(Hashtable library, BufferedReader contents, boolean resolve)
Create a new block of code.

RASMCode(String name, Hashtable library)
Create a new block of code.

RASMCode(String name, Hashtable library, boolean resolve)
Create a new block of code.

RASMCode(String name, Hashtable library, BufferedReader contents)
Create a new block of code.

RASMCode(String name, Hashtable library, BufferedReader contents, boolean resolve)
Create a new block of code.

Method Summary

void	addInstruction(Instruction instr) Add an instruction to the block of code.
RASMCode.Label	defineLabel(String label) Define a new label with the given name.
Instruction	getInstr(int location) Get the instruction at the given location.
RASMCode.Label	getLabel(String label) Get the label whose name is that given.
static Hashtable	getStandardLibrary() Get a reference to the standard library.
void	loadContents(BufferedReader reader) Assemble from a character stream.
Type	parseType(String s) Convert a string to a type in the context of this code block.
String	print(int locn) Print the instruction at the given location.
String	print(int from, int to) Print the instructions in the given range.
protected RASMCode.Label	resolveLabel(String label) Resolve a string to a label.
void	resolveLabels() Link the block of code.
String	toString() Get the name of the block of code.
void	useLabel(RASMCode.Label label) Add a reference to the given label.
void	useLabel(String label) Add a reference to the label with the given name.

Methods inherited from class java.lang.Object

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

Field Detail

MODULE_SEPARATOR

public static final String MODULE_SEPARATOR

The module/label string separator. This separates the name of the module from the name of the label within that module in a far (non-local) label. Local labels do not contain this string.

See Also:

useLabel(String), resolveLabels()

COMMENT_STARTER

public static final char COMMENT_STARTER

Indicates that this line of RASM text is a comment.

LABEL_STARTER

public static final char LABEL_STARTER

Indicates that this line of RASM text is a label definition.

MODULE_COMMAND

public static final String MODULE_COMMAND

A module command starts with this opcode.

CONSTANT_COMMAND

public static final String CONSTANT_COMMAND

A constant command starts with this opcode.

TYPE_COMMAND

public static final String TYPE_COMMAND

A type command starts with this opcode.

PUSH_COMMAND

public static final String PUSH_COMMAND

A push command starts with this opcode.

LABEL_PREFIX

public static final String LABEL_PREFIX

Label references are preceded by this string.

STRING_PREFIX

public static final String STRING_PREFIX

String references are preceded by this string.

TYPE_PREFIX

public static final String TYPE_PREFIX

Type references are preceded by this string.

ARG_PREFIX

public static final String ARG_PREFIX

Argument references are preceded by this string.

STDLIB_PROPERTY_NAME

public static final String STDLIB_PROPERTY_NAME

The name of the property to read the standard library from.

RASM_EXTENSION

public static final String RASM_EXTENSION

The extension for a RASM file.

Constructor Detail

RASMCode

public RASMCode(String name,
                Hashtable library)

Create a new block of code.

Parameters:

name - The name of the block of code.

library - The group of other blocks that labels in this block of code can refer to.

RASMCode

public RASMCode(String name,
                Hashtable library,
                boolean resolve)

Create a new block of code.

Parameters:

name - The name of the block of code.

library - The group of other blocks that labels in this block of code can refer to.

resolve - Indicate whether to resolve all library references automatically on completion of the loading of code.

RASMCode

public RASMCode(String name,
                Hashtable library,
                BufferedReader contents)
         throws RASMCode.Exception,
                IOException,
                TypeException,
                TclFormatException

Create a new block of code. This will have the contents defined by the RASM text on the given stream.

Parameters:

name - The name of the block of code.

library - The group of other blocks that labels in this block of code can refer to.

contents - The stream of RASM text that defines the instructions and labels in this block of code.

See Also:

loadContents(BufferedReader)

RASMCode

public RASMCode(String name,
                Hashtable library,
                BufferedReader contents,
                boolean resolve)
         throws RASMCode.Exception,
                IOException,
                TypeException,
                TclFormatException

Create a new block of code. This will have the contents defined by the RASM text on the given stream.

Parameters:

name - The name of the block of code.

library - The group of other blocks that labels in this block of code can refer to.

contents - The stream of RASM text that defines the instructions and labels in this block of code.

resolve - Indicate whether to resolve all library references automatically on completion of the loading of code.

See Also:

loadContents(BufferedReader)

RASMCode

public RASMCode(Hashtable library,
                BufferedReader contents)
         throws RASMCode.Exception,
                IOException,
                TypeException,
                TclFormatException

Create a new block of code. This will have the contents defined by the RASM text on the given stream, and the name of the block of code will be deduced from the module declaration at the front of the block of code.

Parameters:

library - The group of other blocks that labels in this block of code can refer to.

contents - The stream of RASM text that defines the instructions and labels in this block of code.

See Also:

loadContents(BufferedReader)

RASMCode

public RASMCode(Hashtable library,
                BufferedReader contents,
                boolean resolve)
         throws RASMCode.Exception,
                IOException,
                TypeException,
                TclFormatException

Create a new block of code. This will have the contents defined by the RASM text on the given stream, and the name of the block of code will be deduced from the module declaration at the front of the block of code.

Parameters:

library - The group of other blocks that labels in this block of code can refer to.

contents - The stream of RASM text that defines the instructions and labels in this block of code.

resolve - Indicate whether to resolve all library references automatically on completion of the loading of code.

See Also:

loadContents(BufferedReader)

Method Detail

getStandardLibrary

public static Hashtable getStandardLibrary()

Get a reference to the standard library. Note that you can add your own RASMCode blocks to this without polluting the namespace between compilations since you are really getting a clone of the standard library.

Returns:

A library reference that contains the standard library components.

toString

public String toString()

Get the name of the block of code.

Overrides:

toString in class Object

Returns:

The name of the block of code.

getInstr

public Instruction getInstr(int location)

Get the instruction at the given location.

Parameters:

location - The address in this block of code to get the instruction from.

Returns:

The instruction at the location specified.

Throws:

RainbowError - If the code has not yet been linked.

getLabel

public RASMCode.Label getLabel(String label)

Get the label whose name is that given. The label must be defined.

Parameters:

label - The name of the label to return.

Returns:

The label whose name was given.

Throws:

RuntimeException - If the label is unknown at this point.

defineLabel

public RASMCode.Label defineLabel(String label)

Define a new label with the given name. The label will refer to the next instruction to be added to the block of code.

Parameters:

label - The name of the label to return.

Returns:

The label whose name was given.

Throws:

RainbowError - If the code has already been linked.

addInstruction

public void addInstruction(Instruction instr)

Add an instruction to the block of code. The instruction will be appended to the code block.

Parameters:

instr - The instruction to add.

Throws:

RainbowError - If the code has already been linked.

useLabel

public void useLabel(RASMCode.Label label)

Add a reference to the given label. The instruction added will push the label onto the stack when executed.

Parameters:

label - The label to refer to.

See Also:

addInstruction(Instruction)

useLabel

public void useLabel(String label)

Add a reference to the label with the given name. The instruction added will push the label onto the stack when executed. If the label does not yet exist, this reference will be resolved when this block of code is linked.

Parameters:

label - The name of label to refer to. May also be the name of a label in another block of code.

See Also:

addInstruction(Instruction)

resolveLabels

public void resolveLabels()
                   throws RASMCode.Exception

Link the block of code. Resolves all labels which are only known by their string names to the concrete labels that they represent. Can also handle linking between blocks of code (so long as they are all part of the same group of blocks.) The resolved labels are patched into the correct location in the block of code.

Throws:

RASMCode.Exception - If there is an unresolvable label.

RainbowError - If the block of code has already been linked.

See Also:

resolveLabel(String)

resolveLabel

protected RASMCode.Label resolveLabel(String label)
                               throws RASMCode.Exception

Resolve a string to a label. If the string contains a module separator the label is looked up in the remote code block (found by searching in the list of associated blocks supplied in the constructor) using a recursive call. If the string contains no module separator, then the label is looked up locally.

Parameters:

label - The name of the label to look up.

Returns:

The label with the given name.

Throws:

RASMCode.Exception - If the label cannot be resolved.

See Also:

MODULE_SEPARATOR

print

public String print(int from,
                    int to)

Print the instructions in the given range. Includes embedded labels.

Parameters:

from - The location of the first instruction to print. Will be set to 0 internally if less than 0.

to - One greater than the location of the last instruction to print. Will be set to one past the last instruction in the block of code if past that point.

Returns:

A printable version of the instructions between the given locations. Will also include any labels embedded within the code.

print

public String print(int locn)

Print the instruction at the given location. Includes embedded labels.

Parameters:

locn - The location of the instruction to print.

Returns:

The printable version of the instruction at the given location, plus any labels at that location.

See Also:

print(int,int)

parseType

public final Type parseType(String s)
                     throws TypeException

Convert a string to a type in the context of this code block.

Parameters:

s - The string to parse.

Returns:

The type represented by the string.

Throws:

TypeException - If the string is not a valid type.

loadContents

public void loadContents(BufferedReader reader)
                  throws RASMCode.Exception,
                         IOException,
                         TypeException,
                         TclFormatException

Assemble from a character stream. Loads the contents of the stream into this code block.

Parameters:

reader - The character stream to read from.

Throws:

RASMCode.Exception - If there is a malformatted instruction.

TypeException - If the parsing of a data value or type fails.

TclFormatException - If the input stream doesn't meet standard Tcl-style formatting rules.

IOException - If the input stream ends unexpectedly.

RainbowError - If the code block has already been linked.