Package mars.mips.instructions

Class ExtendedInstruction

java.lang.Object

mars.mips.instructions.Instruction

mars.mips.instructions.ExtendedInstruction

public class ExtendedInstruction
extends Instruction

Representation of an extended instruction, also known as a pseudo-instruction. Unlike basic instructions, extended instructions do not exist at the hardware level. Instead, the assembler expands them into one or more basic instructions which carry out the intended behavior.

Author:

Pete Sanderson, August 2003

See Also:

• BasicInstruction
• ExpansionTemplate

Field Summary

Fields inherited from class mars.mips.instructions.Instruction

BYTES_PER_INSTRUCTION, INSTRUCTION_LENGTH_BITS

Constructor Summary

Constructors

Constructor	Description
ExtendedInstruction(String mnemonic, List<OperandType> operandTypes, String title, String description)	Create a new ExtendedInstruction.

Method Summary

Modifier and Type	Method	Description
ExpansionTemplate	getCompactExpansionTemplate()	Get ArrayList of Strings that represent list of templates for basic instructions generated by the "compact" or 16-bit version of this extended instruction.
ExpansionTemplate	getExpansionTemplate()
int	getSizeBytes()	Get length in bytes that this extended instruction requires in its binary form.
ExpansionTemplate	getStandardExpansionTemplate()	Get ArrayList of Strings that represent list of templates for basic instructions generated by this extended instruction.
boolean	hasCompactVariant()	Determine whether or not this pseudo-instruction has a second translation optimized for 16 bit address space: a compact version.
void	setCompactExpansionTemplate(ExpansionTemplate template)
void	setStandardExpansionTemplate(ExpansionTemplate template)

Methods inherited from class mars.mips.instructions.Instruction

acceptsOperands, acceptsOperandsLoosely, formatOperands, formatSyntax, generateExampleOperands, getAlignedExampleSyntax, getDescription, getExampleOperands, getExampleSyntax, getMnemonic, getOperandTypes, getTitle

Methods inherited from class java.lang.Object

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

Constructor Details

ExtendedInstruction

public ExtendedInstruction(String mnemonic,
 List<OperandType> operandTypes,
 String title,
 String description)

Create a new ExtendedInstruction.

Parameters:

mnemonic - The instruction mnemonic used in assembly code (case-insensitive).

operandTypes - The list of operand types for this instruction, which is used to select a specific instruction from the group of instructions sharing a mnemonic.

title - The "long name" of this instruction, which should relate to the mnemonic.

description - A short human-readable description of what this instruction does when executed.

Method Details

hasCompactVariant

public boolean hasCompactVariant()

Determine whether or not this pseudo-instruction has a second translation optimized for 16 bit address space: a compact version.

getStandardExpansionTemplate

public ExpansionTemplate getStandardExpansionTemplate()

Get ArrayList of Strings that represent list of templates for basic instructions generated by this extended instruction.

Returns:

ArrayList of Strings.

setStandardExpansionTemplate

public void setStandardExpansionTemplate(ExpansionTemplate template)

getCompactExpansionTemplate

public ExpansionTemplate getCompactExpansionTemplate()

Get ArrayList of Strings that represent list of templates for basic instructions generated by the "compact" or 16-bit version of this extended instruction.

Returns:

ArrayList of Strings. Returns null if the instruction does not have a compact alternative.

setCompactExpansionTemplate

public void setCompactExpansionTemplate(ExpansionTemplate template)

getExpansionTemplate

public ExpansionTemplate getExpansionTemplate()

getSizeBytes

public int getSizeBytes()

Get length in bytes that this extended instruction requires in its binary form. The answer depends on how many basic instructions it expands to. This may vary, if expansion includes a nop, depending on whether or not delayed branches are enabled. Each requires 4 bytes.

Specified by:

getSizeBytes in class Instruction

Returns:

int length in bytes of corresponding binary instruction(s).