Enum Class FoldedArithmetic

java.lang.Object

java.lang.Enum<FoldedArithmetic>

ghidra.pcode.emu.jit.folding.FoldedArithmetic

All Implemented Interfaces:

PcodeArithmetic<MaskedBytes>, Serializable, Comparable<FoldedArithmetic>, Constable

public enum FoldedArithmetic
extends Enum<FoldedArithmetic>
implements PcodeArithmetic<MaskedBytes>

The arithmetic for computing folded constants

For the most part, the result of any operation is only known if all inputs are known. In that case, the result is equivalent to applying BytesPcodeArithmetic. Otherwise, the result is completely unknown. Special treatment is given to bitwise boolean operators, extension operators, and shift operators. We also give some special treatment for operators that only modify the sign bit, e.g., PcodeOp.FLOAT_ABS.

Nested Class Summary

Nested classes/interfaces inherited from class Enum

Enum.EnumDesc<E>

Nested classes/interfaces inherited from interface PcodeArithmetic

PcodeArithmetic.Purpose

Enum Constant Summary

Enum Constants

Enum Constant	Description
BE	The big-endian instance
LE	The little-endian instance

Field Summary

Fields inherited from interface PcodeArithmetic

SIZEOF_SIZEOF

Method Summary

Modifier and Type	Method	Description
MaskedBytes	binaryOp(int opcode, int sizeout, int sizein1, MaskedBytes in1, int sizein2, MaskedBytes in2)	Apply a binary operator to the given inputs
static FoldedArithmetic	forEndian(Endian endian)	Returns the instance for the given endian.
static FoldedArithmetic	forLanguage(Language language)	Returns the instance for the given language.
MaskedBytes	fromConst(byte[] value)	Convert the given constant concrete value to type T having the same size.
Class<MaskedBytes>	getDomain()	Get the type of values over which this arithmetic operates.
Endian	getEndian()	Get the endianness of this arithmetic
MaskedBytes	modAfterLoad(int sizeinOffset, AddressSpace space, MaskedBytes inOffset, int sizeinValue, MaskedBytes inValue)	Apply any modifications after a value is loaded
MaskedBytes	modBeforeStore(int sizeinOffset, AddressSpace space, MaskedBytes inOffset, int sizeinValue, MaskedBytes inValue)	Apply any modifications before a value is stored
long	sizeOf(MaskedBytes value)	Get the size in bytes, if possible, of the given abstract value
byte[]	toConcrete(MaskedBytes value, PcodeArithmetic.Purpose purpose)	Convert, if possible, the given abstract value to a concrete byte array
MaskedBytes	unaryOp(int opcode, int sizeout, int sizein1, MaskedBytes in1)	Apply a unary operator to the given input
static FoldedArithmetic	valueOf(String name)	Returns the enum constant of this class with the specified name.
static FoldedArithmetic[]	values()	Returns an array containing the constants of this enum class, in the order they are declared.

Methods inherited from class Enum

clone, compareTo, describeConstable, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface PcodeArithmetic

binaryOp, fromConst, fromConst, fromConst, fromConst, fromConst, fromConst, fromConst, fromConst, fromConst, fromConst, fromConst, fromConstSigned, fromConstSigned, fromConstSigned, fromConstSigned, isTrue, modAfterLoad, modBeforeStore, ptrAdd, ptrSub, sizeOfAbstract, toAddress, toBigInteger, toDouble, toFloat, toLong, toLongSigned, toRegisterValue, unaryOp

Enum Constant Details

BE

public static final FoldedArithmetic BE

The big-endian instance

LE

public static final FoldedArithmetic LE

The little-endian instance

Method Details

values

public static FoldedArithmetic[] values()

Returns an array containing the constants of this enum class, in the order they are declared.

Returns:

an array containing the constants of this enum class, in the order they are declared

valueOf

public static FoldedArithmetic valueOf(String name)

Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum class has no constant with the specified name

NullPointerException - if the argument is null

forEndian

public static FoldedArithmetic forEndian(Endian endian)

Returns the instance for the given endian.

Parameters:

endian - the endian

Returns:

the instance for the given endian

forLanguage

public static FoldedArithmetic forLanguage(Language language)

Returns the instance for the given language.

Parameters:

language - the language

Returns:

the instance for the given language

getDomain

public Class<MaskedBytes> getDomain()

Description copied from interface: PcodeArithmetic

Get the type of values over which this arithmetic operates.

Specified by:

getDomain in interface PcodeArithmetic<MaskedBytes>

Returns:

the domain

getEndian

public Endian getEndian()

Description copied from interface: PcodeArithmetic

Get the endianness of this arithmetic

Often T is a byte array, or at least represents one abstractly. Ideally, it is an array where each element is an abstraction of a byte. If that is the case, then the arithmetic likely has to interpret those bytes as integral values according to an endianness. This should return that endianness.

If the abstraction has no notion of endianness, return null. In that case, the both PcodeArithmetic.fromConst(BigInteger, int, boolean) and PcodeArithmetic.fromConst(long, int) must be overridden. Furthermore, unless PcodeArithmetic.toConcrete(Object, Purpose) is guaranteed to throw an exception, then PcodeArithmetic.toBigInteger(Object, Purpose) and PcodeArithmetic.toLong(Object, Purpose) must also be overridden.

Specified by:

getEndian in interface PcodeArithmetic<MaskedBytes>

Returns:

the endianness or null

unaryOp

public MaskedBytes unaryOp(int opcode,
 int sizeout,
 int sizein1,
 MaskedBytes in1)

Description copied from interface: PcodeArithmetic

Apply a unary operator to the given input

Note the sizes of variables are given, because values don't necessarily have an intrinsic size. For example, a BigInteger may have a minimum encoding size, but that does not necessarily reflect the size of the variable from which is was read.

Specified by:

unaryOp in interface PcodeArithmetic<MaskedBytes>

Parameters:

opcode - the p-code opcode

sizeout - the size (in bytes) of the output variable

sizein1 - the size (in bytes) of the input variable

in1 - the input value

Returns:

the output value

binaryOp

public MaskedBytes binaryOp(int opcode,
 int sizeout,
 int sizein1,
 MaskedBytes in1,
 int sizein2,
 MaskedBytes in2)

Description copied from interface: PcodeArithmetic

Apply a binary operator to the given inputs

Note the sizes of variables are given, because values don't necessarily have an intrinsic size. For example, a BigInteger may have a minimum encoding size, but that does not necessarily reflect the size of the variable from which is was read.

Specified by:

binaryOp in interface PcodeArithmetic<MaskedBytes>

Parameters:

opcode - the operation's opcode. See PcodeOp.

sizeout - the size (in bytes) of the output variable

sizein1 - the size (in bytes) of the first (left) input variable

in1 - the first (left) input value

sizein2 - the size (in bytes) of the second (right) input variable

in2 - the second (right) input value

Returns:

the output value

modBeforeStore

public MaskedBytes modBeforeStore(int sizeinOffset,
 AddressSpace space,
 MaskedBytes inOffset,
 int sizeinValue,
 MaskedBytes inValue)

Description copied from interface: PcodeArithmetic

Apply any modifications before a value is stored

This implements any abstractions associated with PcodeOp.STORE. This is called on the offset and the value before the value is actually stored into the state. NOTE: STORE ops always quantize the offset.

Specified by:

modBeforeStore in interface PcodeArithmetic<MaskedBytes>

Parameters:

sizeinOffset - the size (in bytes) of the variable used for indirection

space - the address space

inOffset - the value used as the address (or offset)

sizeinValue - the size (in bytes) of the variable to store and of the output variable

inValue - the value to store

Returns:

the modified value to store

modAfterLoad

public MaskedBytes modAfterLoad(int sizeinOffset,
 AddressSpace space,
 MaskedBytes inOffset,
 int sizeinValue,
 MaskedBytes inValue)

Description copied from interface: PcodeArithmetic

Apply any modifications after a value is loaded

This implements any abstractions associated with PcodeOp.LOAD. This is called on the address/offset and the value after the value is actually loaded from the state. NOTE: LOAD ops always quantize the offset.

Specified by:

modAfterLoad in interface PcodeArithmetic<MaskedBytes>

Parameters:

sizeinOffset - the size (in bytes) of the variable used for indirection

space - the address space

inOffset - the value used as the offset

sizeinValue - the size (in bytes) of the variable loaded and of the output variable

inValue - the value loaded

Returns:

the modified value loaded

fromConst

public MaskedBytes fromConst(byte[] value)

Description copied from interface: PcodeArithmetic

Convert the given constant concrete value to type T having the same size.

Specified by:

fromConst in interface PcodeArithmetic<MaskedBytes>

Parameters:

value - the constant value

Returns:

the value as a T

toConcrete

public byte[] toConcrete(MaskedBytes value,
 PcodeArithmetic.Purpose purpose)

Description copied from interface: PcodeArithmetic

Convert, if possible, the given abstract value to a concrete byte array

Specified by:

toConcrete in interface PcodeArithmetic<MaskedBytes>

Parameters:

value - the abstract value

purpose - the purpose for which the emulator needs a concrete value

Returns:

the array

sizeOf

public long sizeOf(MaskedBytes value)

Description copied from interface: PcodeArithmetic

Get the size in bytes, if possible, of the given abstract value

If the abstract value does not conceptually have a size, throw an exception.

Specified by:

sizeOf in interface PcodeArithmetic<MaskedBytes>

Parameters:

value - the abstract value

Returns:

the size in bytes