org.jikesrvm.osr

Class LocalRegPair

java.lang.Object

org.jikesrvm.osr.LocalRegPair

public class LocalRegPair
extends Object

An LocalRegPair keeps the type information and location of a local variable/stack slot from byte code to machine code.

Field Summary

Fields

Modifier and Type	Field and Description
LocalRegPair	_otherHalf A LONG variable takes two symbolic registers, we need to know another half part.
boolean	kind is it a local or stack?
int	num what's the number of local of stack
Operand	operand What's the register operand, from which we can get the symbolic register.
byte	typeCode what's the type code?
Word	value The meaning of value field depends on valueType: for ICONST, ACONST and LCONST, it is the value of the constant, for PHYREG, it is the register number, for SPILL, it is the spill location.
byte	valueType A reg value could be an integer constant (ICONST), a physical register (PHYREG), or a spill on the stack (SPILL).

Constructor Summary

Constructors

Constructor and Description
LocalRegPair(boolean kind, int num, byte type, Operand op)

Method Summary

Modifier and Type	Method and Description
LocalRegPair	copy()
String	toString() converts tuple to string as ( L/S num, type, valueType, value, operand )

Methods inherited from class java.lang.Object

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

Field Detail

kind

public final boolean kind

is it a local or stack?

num

public int num

what's the number of local of stack

typeCode

public final byte typeCode

what's the type code? ('I', 'J', 'D', etc)

operand

public final Operand operand

What's the register operand, from which we can get the symbolic register. The operand could be symbolic register, or constants, we need to take it out later.

valueType

public byte valueType

A reg value could be

• an integer constant (ICONST),
• a physical register (PHYREG), or
• a spill on the stack (SPILL).

The valueType is one of them, combined with the typeCode, one should be able to recover the value of a variable.

value

public Word value

The meaning of value field depends on valueType:

• for ICONST, ACONST and LCONST, it is the value of the constant,
• for PHYREG, it is the register number,
• for SPILL, it is the spill location.

_otherHalf

public LocalRegPair _otherHalf

A LONG variable takes two symbolic registers, we need to know another half part.

Constructor Detail

LocalRegPair

public LocalRegPair(boolean kind,
                    int num,
                    byte type,
                    Operand op)

Method Detail

copy

public LocalRegPair copy()

toString

public String toString()

converts tuple to string as ( L/S num, type, valueType, value, operand )

Overrides:

toString in class Object