scale.backend.x86
Class X86Instruction

java.lang.Object
  scale.backend.Instruction
      scale.backend.x86.X86Instruction

All Implemented Interfaces:

java.lang.Cloneable

Direct Known Subclasses:

X86DInstruction, X86RInstruction

public class X86Instruction
extends Instruction

This is the base class for all X86 instructions except branches.

$Id$

Copyright 2008 by James H. Burrill
All Rights Reserved.

Field Summary

protected int	opcode The instruction opcode.
protected byte	setCC flags that specify the condition codes set by the instruction
protected byte	useCC flags that specify the condition codes used by the instruction

Constructor Summary

X86Instruction(int opcode)

Method Summary

java.lang.String	assembleDisp(Assembler asm, Displacement disp, int ftn) Generate a String representation of a Displacement that can be used by the assembly code generater.
void	assembler(Assembler asm, Emit emit) Insert the assembler representation of the instruction into the output stream.
static void	buildAddress(java.lang.StringBuffer buf, int baseReg, int indexReg, Displacement disp, int scale)
boolean	canBeDeleted(RegisterSet registers) Return true if the instruction can be deleted without changing program semantics.
protected boolean	checkForm(int opcode) Return true if the specified form is valid for this instruction opcode.
boolean	defs(int register, RegisterSet registers) Return true if the instruction sets the register.
Displacement	getDisplacement()
Displacement	getDisplacement2()
int	getOpcode() Return the numeric opcode of the instruction.
int	getOperandSize() Return 1, 2, 4, or 8 depending on the size of the operand, in bytes, specified for the instruction.
char	getOperandSizeLabel() Return 'b', 'w', 'l', or 'x' depending on the size of the operand specified for the instruction.
int	getReg()
int	getReg2()
int	getReg3()
int	getScale() Return 1, 2, 4, or 8 depending on the scale factor specified for the instruction.
boolean	independent(Instruction inst, RegisterSet registers) Return true if this instruction is independent of the specified instruction.
protected boolean	independentCC(X86Instruction inst) Return true if this instruction's CC use is independent of the specified instruction.
int	instructionSize() Return the number of bytes required for this instruction.
boolean	isReversed() Return true if the instruction modifies memory.
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 disp)
void	setDisplacement2(Displacement disp)
protected void	setOpcode(int opcode)
void	setOperandSize(int size) Set the operand size specified for the instruction.
void	setReg(int reg)
void	setReg2(int reg2)
void	setReg3(int reg3)
void	setScale(int scale) ((X86Assembler) Set the scale factor specified for the instruction.
boolean	setsCC(int cc) Return true if the instruction sets the CC flag specified.
void	setSetCC(int cc) Specify the CC set by this instruction.
boolean	setsSpecialReg() Return true if this instruction has a side effect of changing a special register.
void	setUseCC(int cc) Specify the CCs used by this instruction.
void	specifyRegisterUsage(RegisterAllocator rs, int index, int strength) Specify the registers used and defined by this instruction.
java.lang.String	toString()
boolean	uses(int register, RegisterSet registers) Return true if the instruction uses the register.
boolean	usesCC(int cc) Return true if the instruction uses the CC flag specified.

Methods inherited from class scale.backend.Instruction

clone, copy, ehash, getBBID, getCopyDest, getCopySrc, getDestRegister, getExecutionCycles, getFunctionalUnit, getLoopNumber, getNext, getPredicate, getPredicates, getSrcRegisters, getTag, isBranch, isCopy, 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, 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.

setCC

protected byte setCC

flags that specify the condition codes set by the instruction

useCC

protected byte useCC

flags that specify the condition codes used by the instruction

Constructor Detail

X86Instruction

public X86Instruction(int opcode)

Parameters:

opcode - is the instruction's opcode

Method Detail

checkForm

protected boolean checkForm(int opcode)

Return true if the specified form is valid for this instruction opcode.

getOpcode

public final 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 final void setOpcode(int opcode)

isReversed

public final boolean isReversed()

Return true if the instruction modifies memory.

getDisplacement

public Displacement getDisplacement()

setDisplacement

public void setDisplacement(Displacement disp)

getDisplacement2

public Displacement getDisplacement2()

setDisplacement2

public void setDisplacement2(Displacement disp)

getReg

public int getReg()

setReg

public void setReg(int reg)

getReg2

public int getReg2()

setReg2

public void setReg2(int reg2)

getReg3

public int getReg3()

setReg3

public void setReg3(int reg3)

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

instructionSize

public int instructionSize()

Return the number of bytes required for this instruction.

Specified by:

instructionSize in class Instruction

setSetCC

public final void setSetCC(int cc)

Specify the CC set by this instruction.

setUseCC

public final void setUseCC(int cc)

Specify the CCs used by this instruction.

setsCC

public final boolean setsCC(int cc)

Return true if the instruction sets the CC flag specified.

Parameters:

cc - specifies the CC

setsSpecialReg

public boolean setsSpecialReg()

Return true if this instruction has a side effect of changing a special register. An example would be a condition code register for architectures that set the condition and tehn branch on it such as the X86.

Overrides:

setsSpecialReg in class Instruction

usesCC

public final boolean usesCC(int cc)

Return true if the instruction uses the CC flag specified.

Parameters:

cc - specifies the CC

independentCC

protected final boolean independentCC(X86Instruction inst)

Return true if this instruction's CC use 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.

Parameters:

inst - is the specified instruction

specifyRegisterUsage

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

Specify the registers used and defined by this instruction. Uses must be specified before definitions.

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)

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

canBeDeleted

public boolean canBeDeleted(RegisterSet registers)

Return true if the instruction can be deleted without changing program semantics.

Overrides:

canBeDeleted in class Instruction

independent

public boolean independent(Instruction inst,
                           RegisterSet registers)

Description copied from class: Instruction

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

remapDestRegister

public void remapDestRegister(int oldReg,
                              int newReg)

Description copied from class: Instruction

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

remapSrcRegister

public void remapSrcRegister(int oldReg,
                             int newReg)

Description copied from class: Instruction

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

assembleDisp

public java.lang.String assembleDisp(Assembler asm,
                                     Displacement disp,
                                     int ftn)

Generate a String representation of a Displacement that can be used by the assembly code generater.

getScale

public int getScale()

Return 1, 2, 4, or 8 depending on the scale factor specified for the instruction.

setScale

public void setScale(int scale)

((X86Assembler) Set the scale factor specified for the instruction. The value must be 1, 2, 4, or 8.

getOperandSize

public int getOperandSize()

Return 1, 2, 4, or 8 depending on the size of the operand, in bytes, specified for the instruction.

getOperandSizeLabel

public char getOperandSizeLabel()

Return 'b', 'w', 'l', or 'x' depending on the size of the operand specified for the instruction.

setOperandSize

public void setOperandSize(int size)

Set the operand size specified for the instruction. The value must be 1, 2, 4, or 8.

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 java.lang.Object

buildAddress

public static void buildAddress(java.lang.StringBuffer buf,
                                int baseReg,
                                int indexReg,
                                Displacement disp,
                                int scale)