scale.backend.alpha
Class BranchInstruction

java.lang.Object
  scale.backend.Instruction
      scale.backend.Branch
          scale.backend.alpha.BranchInstruction

All Implemented Interfaces:

java.lang.Cloneable

public final class BranchInstruction
extends Branch

This class represents Alpha Branch instructions.

$Id: BranchInstruction.java,v 1.29 2007-10-04 19:57:51 burrill Exp $

Copyright 2005 by the Scale Compiler Group,
Department of Computer Science
University of Massachusetts,
Amherst MA. 01003, USA
All Rights Reserved.

Constructor Summary

BranchInstruction(int opcode, int ra, Displacement displacement, int numTargets)

Method Summary

void	assembler(Assembler asm, Emit emit) Insert the assembler representation of the instruction into the output stream.
boolean	defs(int register, RegisterSet registers) Return true if the instruction sets the register
int	getExecutionCycles() Return the number of cycles that this instruction requires.
int	getFunctionalUnit() Return the number of the functional unit required to execute this instruction.
int	getOpcode() Return the numeric opcode of the instruction.
int	getTestRegister()
int	instructionSize() Return the number of bytes required for the BranchInstruction.
boolean	mods(int register, RegisterSet registers) Return true if the instruction clobbers the register.
void	remapDestRegister(int oldReg, int newReg) Map the registers defined in the instruction as destinations to the specified register.
void	remapRegisters(int[] map) Map the virtual registers referenced in the instruction to the specified real registers.
void	remapSrcRegister(int oldReg, int newReg) Map the registers used in the instruction as sources to the specified register.
void	setDisplacement(Displacement displacement) After all of the instructions have been created, the Alpha Branch displacements must be calculated.
protected void	setOpcode(int opcode)
void	specifyRegisterUsage(RegisterAllocator rs, int index, int strength) Specify the registers used by this instruction.
java.lang.String	toString()
boolean	uses(int register, RegisterSet registers) Return true if the instruction uses the register.

Methods inherited from class scale.backend.Branch

additionalRegsKilled, additionalRegsSet, additionalRegsUsed, addTarget, copy, getBranchProbability, getRegsKilled, getTarget, independent, isBranch, isCall, markAsCall, nullify, numTargets, setBranchProbability, uses

Methods inherited from class scale.backend.Instruction

canBeDeleted, clone, ehash, getBBID, getCopyDest, getCopySrc, getDestRegister, getLoopNumber, getNext, getPredicate, getPredicates, getSrcRegisters, getTag, isCopy, isLabel, isLoad, isMandatory, isMarker, isPhi, isPredicated, isPredicatedOnTrue, isPrefetch, isSpillInstruction, isSpillLoadPoint, isSpillStorePoint, isStore, markSpillInstruction, nullified, numPredicates, removePredicates, setBBID, setLoopNumber, setMandatory, setNext, setPredicate, setPredicate, setPredicatedOnTrue, setPredicates, setsSpecialReg, setTag, specifyNotSpillLoadPoint, specifySpillStorePoint

Methods inherited from class java.lang.Object

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

Constructor Detail

BranchInstruction

public BranchInstruction(int opcode,
                         int ra,
                         Displacement displacement,
                         int numTargets)

Method Detail

remapRegisters

public void remapRegisters(int[] map)

Map the virtual registers referenced in the instruction to the specified real registers. The mapping is specified using an array that is indexed by the virtual register to return the real register.

Overrides:

remapRegisters in class Branch

Parameters:

map - maps from the virtual register to real register

remapSrcRegister

public void remapSrcRegister(int oldReg,
                             int newReg)

Map the registers used in the instruction as sources to the specified register. If the register is not used as a source register, no change is made.

Overrides:

remapSrcRegister in class Branch

Parameters:

oldReg - is the previous source register

newReg - is the new source register

remapDestRegister

public void remapDestRegister(int oldReg,
                              int newReg)

Map the registers defined in the instruction as destinations to the specified register. If the register is not used as a destination register, no change is made.

Overrides:

remapDestRegister in class Branch

Parameters:

oldReg - is the previous destination register

newReg - is the new destination register

getOpcode

public int getOpcode()

Description copied from class: Instruction

Return the numeric opcode of the instruction. This opcode may be an encoding of the actual instruction opcode.

Specified by:

getOpcode in class Instruction

setOpcode

protected void setOpcode(int opcode)

getTestRegister

public int getTestRegister()

getExecutionCycles

public int getExecutionCycles()

Return the number of cycles that this instruction requires.

Overrides:

getExecutionCycles in class Branch

getFunctionalUnit

public int getFunctionalUnit()

Return the number of the functional unit required to execute this instruction.

Overrides:

getFunctionalUnit in class Instruction

specifyRegisterUsage

public void specifyRegisterUsage(RegisterAllocator rs,
                                 int index,
                                 int strength)

Specify the registers used by this instruction.

Overrides:

specifyRegisterUsage in class Branch

Parameters:

rs - is the register set in use

index - is an index associated with the instruction

strength - is the importance of the instruction

See Also:

RegisterAllocator.useRegister(int,int,int), RegisterAllocator.defRegister(int,int)

uses

public boolean uses(int register,
                    RegisterSet registers)

Return true if the instruction uses the register.

Overrides:

uses in class Branch

defs

public boolean defs(int register,
                    RegisterSet registers)

Return true if the instruction sets the register

Overrides:

defs in class Branch

mods

public boolean mods(int register,
                    RegisterSet registers)

Return true if the instruction clobbers the register.

Overrides:

mods in class Branch

setDisplacement

public void setDisplacement(Displacement displacement)

After all of the instructions have been created, the Alpha Branch displacements must be calculated. This must be done prior to generating the assembly file.

instructionSize

public int instructionSize()

Return the number of bytes required for the BranchInstruction.

Specified by:

instructionSize in class Instruction

assembler

public void assembler(Assembler asm,
                      Emit emit)

Insert the assembler representation of the instruction into the output stream.

Specified by:

assembler in class Instruction

toString

public java.lang.String toString()

Overrides:

toString in class Branch