scale.backend.alpha
Class FltOpInstruction

java.lang.Object
  extended by scale.backend.Instruction
      extended by scale.backend.alpha.FltOpInstruction
All Implemented Interfaces:
java.lang.Cloneable
Direct Known Subclasses:
FltCvtInstruction

public class FltOpInstruction
extends Instruction

This class represents Alpha floating point instructions.

$Id: FltOpInstruction.java,v 1.34 2007-03-27 19:21:55 burrill Exp $

Copyright 2007 by the Scale Compiler Group,
Department of Computer Science
University of Massachusetts,
Amherst MA. 01003, USA
All Rights Reserved.


Field Summary
protected  int opcode
          the instruction opcode
protected  int ra
          the ra register.
protected  int rb
          the rb register.
protected  int rc
          the rc register.
 
Constructor Summary
FltOpInstruction(int opcode, int ra, int rb, int rc)
           
 
Method Summary
 void assembler(Assembler gen, Emit emit)
          Insert the assembler representation of the instruction into the output stream.
 boolean canBeDeleted(RegisterSet registers)
          Return true if the instruction can be deleted without changing program semantics.
static int created()
          Return the number of instances of this class created.
 boolean defs(int register, RegisterSet registers)
          Return true if the instruction sets the register.
 int getCopyDest()
          Return the source register of a copy instruction.
 int getCopySrc()
          Return the source register of a copy instruction.
 int getDestRegister()
          Return the destination register or -1 if none.
 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 getRa()
           
 int getRb()
           
 int getRc()
           
 boolean independent(Instruction inst, RegisterSet registers)
          Return true if this instruction is independent of the specified instruction.
 int instructionSize()
          Return the number of bytes required for the FltOpInstruction.
 boolean isCopy()
          Return true if the instruction copies a value from one register to another without modification.
 boolean match(int ra, int rb, int rc)
           
 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.
protected  void setOpcode(int opcode)
           
protected  void setRa(int ra)
           
 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.Instruction
clone, copy, ehash, getBBID, getLoopNumber, getNext, getPredicate, getPredicates, getSrcRegisters, getTag, isBranch, isLabel, isLoad, isMandatory, isMarker, isPhi, isPredicated, isPredicatedOnTrue, isPrefetch, isSpillInstruction, isSpillLoadPoint, isSpillStorePoint, isStore, markSpillInstruction, mods, nullified, nullify, 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

opcode

protected int opcode
the instruction opcode


ra

protected int ra
the ra register.


rb

protected int rb
the rb register.


rc

protected int rc
the rc register.

Constructor Detail

FltOpInstruction

public FltOpInstruction(int opcode,
                        int ra,
                        int rb,
                        int rc)
Method Detail

created

public static int created()
Return the number of instances of this class created.


getDestRegister

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

Overrides:
getDestRegister in class Instruction

remapRegisters

public void remapRegisters(int[] map)
Description copied from class: Instruction
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.

Specified by:
remapRegisters in class Instruction
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.

Specified by:
remapSrcRegister in class Instruction
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.

Specified by:
remapDestRegister in class Instruction
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)

getRa

public int getRa()

setRa

protected void setRa(int ra)

getRb

public int getRb()

getRc

public int getRc()

match

public boolean match(int ra,
                     int rb,
                     int rc)

specifyRegisterUsage

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

Specified by:
specifyRegisterUsage in class Instruction
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 Instruction

defs

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

Overrides:
defs in class Instruction

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.

Specified by:
independent in class Instruction
Parameters:
inst - is the specified instruction

instructionSize

public int instructionSize()
Return the number of bytes required for the FltOpInstruction.

Specified by:
instructionSize in class Instruction

canBeDeleted

public boolean canBeDeleted(RegisterSet registers)
Return true if the instruction can be deleted without changing program semantics.

Overrides:
canBeDeleted in class Instruction

isCopy

public boolean isCopy()
Return true if the instruction copies a value from one register to another without modification. Transfers between integer and floating point registers are not considered to be copy instructions.

Overrides:
isCopy in class Instruction

getCopySrc

public int getCopySrc()
Return the source register of a copy instruction.

Overrides:
getCopySrc in class Instruction

getCopyDest

public int getCopyDest()
Return the source register of a copy instruction.

Overrides:
getCopyDest in class Instruction

getExecutionCycles

public int getExecutionCycles()
Return the number of cycles that this instruction requires.

Overrides:
getExecutionCycles in class Instruction

getFunctionalUnit

public int getFunctionalUnit()
Return the number of the functional unit required to execute this instruction.

Overrides:
getFunctionalUnit in class Instruction

assembler

public void assembler(Assembler gen,
                      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 java.lang.Object