scale.backend.mips
Class JumpRegInstruction

java.lang.Object
  extended by scale.backend.Instruction
      extended by scale.backend.Branch
          extended by scale.backend.mips.MipsBranch
              extended by scale.backend.mips.JumpRegInstruction
All Implemented Interfaces:
java.lang.Cloneable

public class JumpRegInstruction
extends MipsBranch

This class represents the Mips jump, and jump & link instructions.

$Id: JumpRegInstruction.java,v 1.11 2006-10-04 13:59:19 burrill Exp $

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


Field Summary
protected  boolean link
          whether or not the jump links
protected  int rd
          the rd register
protected  int rs
          the rs register
 
Fields inherited from class scale.backend.mips.MipsBranch
delaySlot, opcode
 
Constructor Summary
JumpRegInstruction(int opcode, int rs, int rd, int numTargets, MipsInstruction delaySlot, boolean link)
           
JumpRegInstruction(int opcode, int rs, int numTargets, MipsInstruction delaySlot, boolean link)
           
 
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 getDestRegister()
          Return the destination register or -1 if none.
 int getRs()
           
 int[] getSrcRegisters()
          Return the source registers or null if none.
 boolean independent(Instruction inst, RegisterSet registers)
          Return true if this instruction is independent of the specified instruction.
 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 specifyRegisterUsage(RegisterAllocator ra, 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.mips.MipsBranch
assembleDelay, assembleDisp, canBeDeleted, delayToStringBuf, getDelaySlot, getOpcode, instructionSize, isUnconditional, mods, setDelaySlot, setOpcode
 
Methods inherited from class scale.backend.Branch
additionalRegsKilled, additionalRegsSet, additionalRegsUsed, addTarget, copy, getBranchProbability, getExecutionCycles, getRegsKilled, getTarget, isBranch, isCall, markAsCall, nullify, numTargets, setBranchProbability, uses
 
Methods inherited from class scale.backend.Instruction
clone, ehash, getBBID, getCopyDest, getCopySrc, getFunctionalUnit, getLoopNumber, getNext, getPredicate, getPredicates, 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
 

Field Detail

rs

protected int rs
the rs register


link

protected boolean link
whether or not the jump links


rd

protected int rd
the rd register

Constructor Detail

JumpRegInstruction

public JumpRegInstruction(int opcode,
                          int rs,
                          int rd,
                          int numTargets,
                          MipsInstruction delaySlot,
                          boolean link)

JumpRegInstruction

public JumpRegInstruction(int opcode,
                          int rs,
                          int numTargets,
                          MipsInstruction delaySlot,
                          boolean link)
Method Detail

getDestRegister

public int getDestRegister()
Return the destination register or -1 if none.

Overrides:
getDestRegister in class Instruction

getSrcRegisters

public int[] getSrcRegisters()
Return the source registers or null if none.

Overrides:
getSrcRegisters in class Instruction

remapRegisters

public void remapRegisters(int[] map)
Description copied from class: MipsBranch
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 MipsBranch
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 MipsBranch
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 MipsBranch
Parameters:
oldReg - is the previous destination register
newReg - is the new destination register

getRs

public int getRs()

uses

public boolean uses(int register,
                    RegisterSet registers)
Return true if the instruction uses the register.

Overrides:
uses in class MipsBranch

defs

public boolean defs(int register,
                    RegisterSet registers)
Return true if the instruction sets the register.

Overrides:
defs in class MipsBranch

independent

public boolean independent(Instruction inst,
                           RegisterSet registers)
Return true if this instruction is independent of the specified instruction. If instructions are independent, than one instruction can be moved before or after the other instruction without changing the semantics of the program.

Overrides:
independent in class Branch
Parameters:
inst - is the specified instruction

specifyRegisterUsage

public void specifyRegisterUsage(RegisterAllocator ra,
                                 int index,
                                 int strength)
Specify the registers used by this instruction.

Overrides:
specifyRegisterUsage in class MipsBranch
Parameters:
ra - is the register allocator 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)

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