com.oracle.graal.compiler.common.type

Class IntegerStamp

java.lang.Object

com.oracle.graal.compiler.common.type.Stamp

com.oracle.graal.compiler.common.type.ArithmeticStamp

com.oracle.graal.compiler.common.type.PrimitiveStamp

com.oracle.graal.compiler.common.type.IntegerStamp

public class IntegerStamp
extends PrimitiveStamp

Describes the possible values of a node that produces an int or long result. The description consists of (inclusive) lower and upper bounds and up (may be set) and down (always set) bit-masks.

Field Summary

Fields

Modifier and Type	Field and Description
private long	downMask
private long	lowerBound
static ArithmeticOpTable	OPS
private long	upMask
private long	upperBound

Constructor Summary

Constructors

Constructor and Description
IntegerStamp(int bits, long lowerBound, long upperBound, long downMask, long upMask)

Method Summary

Modifier and Type	Method and Description
static boolean	addOverflowsNegatively(long x, long y, int bits)
static boolean	addOverflowsPositively(long x, long y, int bits)
JavaConstant	asConstant() If this stamp represents a single value, the methods returns this single value.
boolean	canBeNegative()
boolean	canBePositive()
static long	carryBits(long x, long y)
Stamp	constant(Constant c, MetaAccessProvider meta) If it is possible to represent single value stamps of this kind, this method returns the stamp representing the single value c.
boolean	contains(long value)
private Stamp	createStamp(IntegerStamp other, long newUpperBound, long newLowerBound, long newDownMask, long newUpMask)
SerializableConstant	deserialize(ByteBuffer buffer)
long	downMask() This bit-mask describes the bits that are always set in the value described by this stamp.
Stamp	empty() Returns a stamp of the same kind, but with no allowed values.
boolean	equals(Object obj)
LIRKind	getLIRKind(LIRKindTool tool) Gets a platform dependent LIRKind that can be used to store a value of this stamp.
Kind	getStackKind() Gets a Java Kind that can be used to store a value of this stamp on the Java bytecode stack.
int	hashCode()
boolean	hasValues() Test whether this stamp has legal values.
boolean	isCompatible(Stamp stamp) Test whether two stamps have the same base type.
boolean	isNegative()
boolean	isPositive()
boolean	isStrictlyNegative()
boolean	isStrictlyPositive()
boolean	isUnrestricted()
ResolvedJavaType	javaType(MetaAccessProvider metaAccess) Returns the type of the stamp, guaranteed to be non-null.
Stamp	join(Stamp otherStamp) Returns the intersection of this stamp and the given stamp.
long	lowerBound() The signed inclusive lower bound on the value described by this stamp.
Stamp	meet(Stamp otherStamp) Returns the union of this stamp and the given stamp.
static boolean	sameSign(IntegerStamp s1, IntegerStamp s2) Checks if the 2 stamps represent values of the same sign.
private static long	saturate(long v, int bits)
static IntegerStamp	stampForMask(int bits, long downMask, long upMask)
String	toString()
IntegerStamp	unrestricted() Returns a stamp of the same kind, but allowing the full value range of the kind.
long	upMask() This bit-mask describes the bits that can be set in the value described by this stamp.
static long	upMaskFor(int bits, long lowerBound, long upperBound)
long	upperBound() The signed inclusive upper bound on the value described by this stamp.

Methods inherited from class com.oracle.graal.compiler.common.type.PrimitiveStamp

getBits, getBits, readConstant

Methods inherited from class com.oracle.graal.compiler.common.type.ArithmeticStamp

getOps, improveWith

Methods inherited from class com.oracle.graal.compiler.common.type.Stamp

alwaysDistinct, isEmpty, neverDistinct, tryImproveWith

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

lowerBound

private final long lowerBound

upperBound

private final long upperBound

downMask

private final long downMask

upMask

private final long upMask

OPS

public static final ArithmeticOpTable OPS

Constructor Detail

IntegerStamp

public IntegerStamp(int bits,
                    long lowerBound,
                    long upperBound,
                    long downMask,
                    long upMask)

Method Detail

stampForMask

public static IntegerStamp stampForMask(int bits,
                                        long downMask,
                                        long upMask)

unrestricted

public IntegerStamp unrestricted()

Description copied from class: Stamp

Returns a stamp of the same kind, but allowing the full value range of the kind. Stamp.unrestricted() is the neutral element of the Stamp.join(Stamp) operation.

Specified by:

unrestricted in class Stamp

empty

public Stamp empty()

Description copied from class: Stamp

Returns a stamp of the same kind, but with no allowed values. Stamp.empty() is the neutral element of the Stamp.meet(Stamp) operation.

Specified by:

empty in class Stamp

constant

public Stamp constant(Constant c,
                      MetaAccessProvider meta)

Description copied from class: Stamp

If it is possible to represent single value stamps of this kind, this method returns the stamp representing the single value c. stamp.constant(c).asConstant() should be equal to c.

If it is not possible to represent single value stamps, this method returns a stamp that includes c, and is otherwise as narrow as possible.

Specified by:

constant in class Stamp

deserialize

public SerializableConstant deserialize(ByteBuffer buffer)

Specified by:

deserialize in class ArithmeticStamp

hasValues

public boolean hasValues()

Description copied from class: Stamp

Test whether this stamp has legal values.

Specified by:

hasValues in class Stamp

getStackKind

public Kind getStackKind()

Description copied from class: Stamp

Gets a Java Kind that can be used to store a value of this stamp on the Java bytecode stack. Returns Kind.Illegal if a value of this stamp can not be stored on the bytecode stack.

Specified by:

getStackKind in class Stamp

getLIRKind

public LIRKind getLIRKind(LIRKindTool tool)

Description copied from class: Stamp

Gets a platform dependent LIRKind that can be used to store a value of this stamp.

Specified by:

getLIRKind in class Stamp

javaType

public ResolvedJavaType javaType(MetaAccessProvider metaAccess)

Description copied from class: Stamp

Returns the type of the stamp, guaranteed to be non-null. In some cases, this requires the lookup of class meta data, therefore the MetaAccessProvider is mandatory.

Specified by:

javaType in class Stamp

lowerBound

public long lowerBound()

The signed inclusive lower bound on the value described by this stamp.

upperBound

public long upperBound()

The signed inclusive upper bound on the value described by this stamp.

downMask

public long downMask()

This bit-mask describes the bits that are always set in the value described by this stamp.

upMask

public long upMask()

This bit-mask describes the bits that can be set in the value described by this stamp.

isUnrestricted

public boolean isUnrestricted()

contains

public boolean contains(long value)

isPositive

public boolean isPositive()

isNegative

public boolean isNegative()

isStrictlyPositive

public boolean isStrictlyPositive()

isStrictlyNegative

public boolean isStrictlyNegative()

canBePositive

public boolean canBePositive()

canBeNegative

public boolean canBeNegative()

toString

public String toString()

Overrides:

toString in class Object

createStamp

private Stamp createStamp(IntegerStamp other,
                          long newUpperBound,
                          long newLowerBound,
                          long newDownMask,
                          long newUpMask)

meet

public Stamp meet(Stamp otherStamp)

Description copied from class: Stamp

Returns the union of this stamp and the given stamp. Typically used to create stamps for phi nodes.

Specified by:

meet in class Stamp

Parameters:

otherStamp - The stamp that will enlarge this stamp.

Returns:

The union of this stamp and the given stamp.

join

public Stamp join(Stamp otherStamp)

Description copied from class: Stamp

Returns the intersection of this stamp and the given stamp.

Specified by:

join in class Stamp

Parameters:

otherStamp - The stamp that will tighten this stamp.

Returns:

The intersection of this stamp and the given stamp.

isCompatible

public boolean isCompatible(Stamp stamp)

Description copied from class: Stamp

Test whether two stamps have the same base type.

Specified by:

isCompatible in class Stamp

hashCode

public int hashCode()

Overrides:

hashCode in class PrimitiveStamp

equals

public boolean equals(Object obj)

Overrides:

equals in class PrimitiveStamp

upMaskFor

public static long upMaskFor(int bits,
                             long lowerBound,
                             long upperBound)

sameSign

public static boolean sameSign(IntegerStamp s1,
                               IntegerStamp s2)

Checks if the 2 stamps represent values of the same sign. Returns true if the two stamps are both positive of null or if they are both strictly negative

Returns:

true if the two stamps are both positive of null or if they are both strictly negative

asConstant

public JavaConstant asConstant()

Description copied from class: Stamp

If this stamp represents a single value, the methods returns this single value. It returns null otherwise.

Overrides:

asConstant in class Stamp

Returns:

the constant corresponding to the single value of this stamp and null if this stamp can represent less or more than one value.

addOverflowsPositively

public static boolean addOverflowsPositively(long x,
                                             long y,
                                             int bits)

addOverflowsNegatively

public static boolean addOverflowsNegatively(long x,
                                             long y,
                                             int bits)

carryBits

public static long carryBits(long x,
                             long y)

saturate

private static long saturate(long v,
                             int bits)