org.jruby.truffle.runtime

Class ObjectIDOperations

java.lang.Object

org.jruby.truffle.runtime.ObjectIDOperations

public abstract class ObjectIDOperations
extends Object

 Object IDs distribution

 We try to respect MRI scheme when it makes sense (Fixnum for the moment).
 Have a look at include/ruby/ruby.h below ruby_special_consts.

 Encoding for Fixnum (long):
 ... 0000 = false
 ... 0010 = true
 ... 0100 = nil

 ... xxx1 = Fixnum of value (id-1)/2 if -2^62 <= value < 2^62
 ... xxx0 = BasicObject generated id (for id > 4)

 Encoding for Bignum:
 ... 0001 | 64-bit long = Fixnum if value < -2^62 or value >= 2^62
 ... 0010 | 64-bit raw double bits = Float
 

Field Summary

Fields

Modifier and Type	Field and Description
static int	FALSE
static int	FIRST_OBJECT_ID
static int	NIL
static int	TRUE

Constructor Summary

Constructors

Constructor and Description
ObjectIDOperations()

Method Summary

Methods

Modifier and Type	Method and Description
static RubyBignum	floatToID(RubyContext context, double value)
static boolean	isFloatID(RubyBignum id)
static boolean	isLargeFixnumID(RubyBignum id)
static boolean	isSmallFixnum(long fixnum)
static boolean	isSmallFixnumID(long id)
static RubyBignum	largeFixnumToID(RubyContext context, long fixnum)
static long	smallFixnumToID(long fixnum)
static long	smallFixnumToIDOverflow(long fixnum)
static long	toFixnum(long id)
static long	toFixnum(RubyBignum id)
static double	toFloat(RubyBignum id)

Methods inherited from class java.lang.Object

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

Field Detail

FALSE

public static final int FALSE

See Also:

Constant Field Values

TRUE

public static final int TRUE

See Also:

Constant Field Values

NIL

public static final int NIL

See Also:

Constant Field Values

FIRST_OBJECT_ID

public static final int FIRST_OBJECT_ID

See Also:

Constant Field Values

Constructor Detail

ObjectIDOperations

public ObjectIDOperations()

Method Detail

isSmallFixnum

public static boolean isSmallFixnum(long fixnum)

smallFixnumToIDOverflow

public static long smallFixnumToIDOverflow(long fixnum)
                                    throws ArithmeticException

Throws:

ArithmeticException

smallFixnumToID

public static long smallFixnumToID(long fixnum)

largeFixnumToID

public static RubyBignum largeFixnumToID(RubyContext context,
                         long fixnum)

floatToID

public static RubyBignum floatToID(RubyContext context,
                   double value)

isSmallFixnumID

public static boolean isSmallFixnumID(long id)

toFixnum

public static long toFixnum(long id)

isLargeFixnumID

public static boolean isLargeFixnumID(RubyBignum id)

toFixnum

public static long toFixnum(RubyBignum id)

isFloatID

public static boolean isFloatID(RubyBignum id)

toFloat

public static double toFloat(RubyBignum id)