Module jdk.incubator.vector
Package jdk.incubator.vector

Interface VectorSpecies<E>

  • Type Parameters:
    E - the boxed element type for the vector element type (ETYPE)
    public interface VectorSpecies<E>
    Interface for managing all vectors of the same combination of element type (ETYPE) and shape.
    API Note:
    User code should not implement this interface. A future release of this type may restrict implementations to be members of the same package.
    Implementation Note:
    The string representation of an instance of this interface will be of the form "Species[ETYPE, VLENGTH, SHAPE]", where ETYPE is the primitive lane type, VLENGTH is the vector lane count associated with the species, and SHAPE is the vector shape associated with the species.

    Vector species objects can be stored in locals and parameters and as static final constants, but storing them in other Java fields or in array elements, while semantically valid, may incur performance penalties.

    • Method Summary

      Modifier and Type Method Description
      Class<?> arrayType()
      Returns the primitive array type ETYPE[], which can carry packed lane values of vectors of this species.
      Vector<E> broadcast​(long e)
      Returns a vector of the given species where all lane elements are set to the primitive value e.
      <F> VectorSpecies<F> check​(Class<F> elementType)
      Checks that this species has the given element type, and returns this species unchanged.
      long checkValue​(long e)
      Checks that this species can represent the given element value, and returns the value unchanged.
      int elementSize()
      Returns the lane size, in bits, of vectors of this species.
      static int elementSize​(Class<?> elementType)
      Returns the bit-size of the given vector element type (ETYPE).
      Class<E> elementType()
      Returns the primitive element type of vectors of this species.
      boolean equals​(Object obj)
      Indicates whether this species is identical to some other object.
      Vector<E> fromArray​(Object a, int offset)
      Returns a vector of this species where lane elements are initialized from the given array at the given offset.
      Vector<E> fromByteArray​(byte[] a, int offset)
      Returns a vector of this species where lane elements are initialized from the given byte array at the given offset.
      Vector<E> fromValues​(long... values)
      Returns a vector of this species where lane elements are initialized from the given sequence of longs.
      Class<E> genericElementType()
      Returns the generic parameter type E corresponding to the element type ETYPE of this species.
      int hashCode()
      Returns a hash code value for the species, based on the vector shape and element type.
      VectorMask<E> indexInRange​(int offset, int limit)
      Returns a mask of this species where only the lanes at index N such that the adjusted index N+offset is in the range [0..limit-1] are set.
      VectorShuffle<E> iotaShuffle​(int start, int step, boolean wrap)
      Creates a shuffle using source indexes set to sequential values starting from start and stepping by the given step.
      int length()
      Returns the number of lanes in a vector of this species.
      VectorMask<E> loadMask​(boolean[] bits, int offset)
      Returns a mask of this species where lane elements are initialized from the given array at the given offset.
      int loopBound​(int length)
      Loop control function which returns the largest multiple of VLENGTH that is less than or equal to the given length value.
      VectorMask<E> maskAll​(boolean bit)
      Returns a mask of this species, where each lane is set or unset according to given single boolean, which is broadcast to all lanes.
      Class<? extends VectorMask<E>> maskType()
      Returns the vector mask type for this species.
      static <E> VectorSpecies<E> of​(Class<E> elementType, VectorShape shape)
      Finds a species for an element type and shape.
      static <E> VectorSpecies<E> ofLargestShape​(Class<E> etype)
      Finds the largest vector species of the given element type.
      static <E> VectorSpecies<E> ofPreferred​(Class<E> etype)
      Finds the species preferred by the current platform for a given vector element type.
      int partLimit​(VectorSpecies<?> outputSpecies, boolean lanewise)
      Given this species and a second one, reports the net expansion or contraction of a (potentially) resizing reinterpretation cast or lane-wise conversion from this species to the second.
      VectorShuffle<E> shuffleFromArray​(int[] sourceIndexes, int offset)
      Creates a shuffle for this species from an int array starting at an offset.
      VectorShuffle<E> shuffleFromOp​(IntUnaryOperator fn)
      Creates a shuffle for this species from the successive values of an operator applied to the range [0..VLENGTH-1].
      VectorShuffle<E> shuffleFromValues​(int... sourceIndexes)
      Creates a shuffle for this species from a series of source indexes.
      String toString()
      Returns a string of the form "Species[ETYPE, VLENGTH, SHAPE]", where ETYPE is the primitive lane type, VLENGTH is the vector lane count associated with the species, and SHAPE is the vector shape associated with the species.
      int vectorBitSize()
      Returns the total vector size, in bits, of any vector of this species.
      int vectorByteSize()
      Returns the total vector size, in bytes, of any vector of this species.
      VectorShape vectorShape()
      Returns the shape of vectors produced by this species.
      Class<? extends Vector<E>> vectorType()
      Returns the vector type of this species.
      <F> VectorSpecies<F> withLanes​(Class<F> newType)
      Finds a species with the given element type and the same shape as this species.
      VectorSpecies<E> withShape​(VectorShape newShape)
      Finds a species with the given shape and the same elementType as this species.
      Vector<E> zero()
      Returns a vector of this species where all lane elements are set to the default primitive value, (ETYPE)0.

    • Method Detail

      • elementType

        Class<E> elementType()
        Returns the primitive element type of vectors of this species.
        Returns:
        the primitive element type (ETYPE)

      • genericElementType

        Class<E> genericElementType()
        Returns the generic parameter type E corresponding to the element type ETYPE of this species.
        Returns:
        the parameter type E

      • arrayType

        Class<?> arrayType()
        Returns the primitive array type ETYPE[], which can carry packed lane values of vectors of this species.
        Returns:
        the primitive array type ETYPE[]

      • vectorType

        Class<? extends Vector<E>> vectorType()
        Returns the vector type of this species. A vector is of this species if and only if it is of the corresponding vector type.
        Returns:
        the vector type of this species

      • maskType

        Class<? extends VectorMask<E>> maskType()
        Returns the vector mask type for this species.
        Returns:
        the mask type

      • elementSize

        int elementSize()
        Returns the lane size, in bits, of vectors of this species.
        Returns:
        the element size, in bits

      • vectorShape

        VectorShape vectorShape()
        Returns the shape of vectors produced by this species.
        Returns:
        the shape of any vectors of this species

      • length

        int length()
        Returns the number of lanes in a vector of this species.
        Returns:
        the number of vector lanes

      • vectorBitSize

        int vectorBitSize()
        Returns the total vector size, in bits, of any vector of this species. This is the same value as this.vectorShape().vectorBitSize().
        Returns:
        the total vector size, in bits

      • vectorByteSize

        int vectorByteSize()
        Returns the total vector size, in bytes, of any vector of this species. This is the same value as this.vectorShape().vectorBitSize() / Byte.SIZE.
        Returns:
        the total vector size, in bytes

      • loopBound

        int loopBound​(int length)
        Loop control function which returns the largest multiple of VLENGTH that is less than or equal to the given length value. Here, VLENGTH is the result of this.length(), and length is interpreted as a number of lanes. The resulting value R satisfies this inequality: 
        R <= length < R+VLENGTH

        Specifically, this method computes length - floorMod(length, VLENGTH), where floorMod computes a remainder value by rounding its quotient toward negative infinity. As long as VLENGTH is a power of two, then the result is also equal to length & ~(VLENGTH - 1).

        Parameters:
        length - the input length
        Returns:
        the largest multiple of the vector length not greater than the given length
        Throws:
        IllegalArgumentException - if the length is negative and the result would overflow to a positive value
        See Also:
        Math.floorMod(int, int)

      • indexInRange

        VectorMask<E> indexInRange​(int offset,
                           int limit)
        Returns a mask of this species where only the lanes at index N such that the adjusted index N+offset is in the range [0..limit-1] are set.

        This method returns the value of the expression maskAll(true).indexInRange(offset, limit)

        Parameters:
        offset - the starting index
        limit - the upper-bound (exlusive) of index range
        Returns:
        a mask with out-of-range lanes unset
        See Also:
        VectorMask.indexInRange(int, int)

      • check

        <F> VectorSpecies<F> check​(Class<F> elementType)
        Checks that this species has the given element type, and returns this species unchanged. The effect is similar to this pseudocode: elementType == elementType() ? this : throw new ClassCastException().
        Type Parameters:
        F - the boxed element type of the required lane type
        Parameters:
        elementType - the required lane type
        Returns:
        the same species
        Throws:
        ClassCastException - if the species has the wrong element type
        See Also:
        Vector.check(Class), Vector.check(VectorSpecies)

      • partLimit

        int partLimit​(VectorSpecies<?> outputSpecies,
              boolean lanewise)
        Given this species and a second one, reports the net expansion or contraction of a (potentially) resizing reinterpretation cast or lane-wise conversion from this species to the second. The sign and magnitude of the return value depends on the size difference between the proposed input and output shapes, and (optionally, if lanewise is true) also on the size difference between the proposed input and output lanes.
        • First, a logical result size is determined. If lanewise is false, this size that of the input VSHAPE. If lanewise is true, the logical result size is the product of the input VLENGTH times the size of the output .
        • Next, the logical result size is compared against the size of the proposed output shape, to see how it will fit.
        • If the logical result fits precisely in the output shape, the return value is zero, signifying no net expansion or contraction.
        • If the logical result would overflow the output shape, the return value is the ratio (greater than one) of the logical result size to the (smaller) output size. This ratio can be viewed as measuring the proportion of "dropped input bits" which must be deleted from the input in order for the result to fit in the output vector. It is also the part limit, a upper exclusive limit on the part parameter to a method that would transform the input species to the output species.
        • If the logical result would drop into the output shape with room to spare, the return value is a negative number whose absolute value the ratio (greater than one) between the output size and the (smaller) logical result size. This ratio can be viewed as measuring the proportion of "extra padding bits" which must be added to the logical result to fill up the output vector. It is also the part limit, an exclusive lower limit on the part parameter to a method that would transform the input species to the output species.
        Parameters:
        outputSpecies - the proposed output species
        lanewise - whether to take lane sizes into account
        Returns:
        an indication of the size change, as a signed ratio or zero
        See Also:
        Vector.reinterpretShape(VectorSpecies,int), Vector.convertShape(VectorOperators.Conversion,VectorSpecies,int)

      • withLanes

        <F> VectorSpecies<F> withLanes​(Class<F> newType)
        Finds a species with the given element type and the same shape as this species. Returns the same value as VectorSpecies.of(newType, this.vectorShape()).
        Type Parameters:
        F - the boxed element type
        Parameters:
        newType - the new element type
        Returns:
        a species for the new element type and the same shape
        Throws:
        IllegalArgumentException - if no such species exists for the given combination of element type and shape or if the given type is not a valid ETYPE
        See Also:
        withShape(VectorShape), of(Class, VectorShape)

      • withShape

        VectorSpecies<E> withShape​(VectorShape newShape)
        Finds a species with the given shape and the same elementType as this species. Returns the same value as VectorSpecies.of(this.elementType(), newShape).
        Parameters:
        newShape - the new shape
        Returns:
        a species for the same element type and the new shape
        Throws:
        IllegalArgumentException - if no such species exists for the given combination of element type and shape
        See Also:
        withLanes(Class), of(Class, VectorShape)

      • of

        static <E> VectorSpecies<E> of​(Class<E> elementType,
                               VectorShape shape)
        Finds a species for an element type and shape.
        Type Parameters:
        E - the boxed element type
        Parameters:
        elementType - the element type
        shape - the shape
        Returns:
        a species for the given element type and shape
        Throws:
        IllegalArgumentException - if no such species exists for the given combination of element type and shape or if the given type is not a valid ETYPE
        See Also:
        withLanes(Class), withShape(VectorShape)

      • ofLargestShape

        static <E> VectorSpecies<E> ofLargestShape​(Class<E> etype)
        Finds the largest vector species of the given element type.

        The returned species is a species chosen by the platform that has a shape with the largest possible bit-size for the given element type. The underlying vector shape might not support other lane types on some platforms, which may limit the applicability of reinterpretation casts. Vector algorithms which require reinterpretation casts will be more portable if they use the platform's preferred species.

        Type Parameters:
        E - the boxed element type
        Parameters:
        etype - the element type
        Returns:
        a preferred species for an element type
        Throws:
        IllegalArgumentException - if no such species exists for the element type or if the given type is not a valid ETYPE
        See Also:
        ofPreferred(Class)

      • ofPreferred

        static <E> VectorSpecies<E> ofPreferred​(Class<E> etype)
        Finds the species preferred by the current platform for a given vector element type. This is the same value as VectorSpecies.of(etype, VectorShape.preferredShape()).

        This species is chosen by the platform so that it has the largest possible shape that supports all lane element types. This has the following implications:

        • The various preferred species for different element types will have the same underlying shape.
        • All vectors created from preferred species will have a common bit-size and information capacity.
        • Reinterpretation casts between vectors of preferred species will neither truncate lanes nor fill them with default values.
        • For any particular element type, some platform might possibly provide a larger vector shape that (as a trade-off) does not support all possible element types.
        Implementation Note:
        On many platforms there is no behavioral difference between ofLargestShape and ofPreferred, because the preferred shape is usually also the largest available shape for every lane type. Therefore, most vector algorithms will perform well without ofLargestShape.
        Type Parameters:
        E - the boxed element type
        Parameters:
        etype - the element type
        Returns:
        a preferred species for this element type
        Throws:
        IllegalArgumentException - if no such species exists for the element type or if the given type is not a valid ETYPE
        See Also:
        Vector.reinterpretShape(VectorSpecies,int), VectorShape.preferredShape(), ofLargestShape(Class)

      • elementSize

        static int elementSize​(Class<?> elementType)
        Returns the bit-size of the given vector element type (ETYPE). The element type must be a valid ETYPE, not a wrapper type or other object type. The element type argument must be a mirror for a valid vector ETYPE, such as byte.class, int.class, or double.class. The bit-size of such a type is the SIZE constant for the corresponding wrapper class, such as Byte.SIZE, or Integer.SIZE, or Double.SIZE.
        Parameters:
        elementType - a vector element type (an ETYPE)
        Returns:
        the bit-size of elementType, such as 32 for int.class
        Throws:
        IllegalArgumentException - if the given elementType argument is not a valid vector ETYPE

      • zero

        Vector<E> zero()
        Returns a vector of this species where all lane elements are set to the default primitive value, (ETYPE)0. Equivalent to IntVector.zero(this) or an equivalent zero method, on the vector type corresponding to this species.
        Returns:
        a zero vector of the given species
        See Also:
        IntVector.zero(VectorSpecies), FloatVector.zero(VectorSpecies)

      • fromArray

        Vector<E> fromArray​(Object a,
                    int offset)
        Returns a vector of this species where lane elements are initialized from the given array at the given offset. The array must be of the the correct ETYPE. Equivalent to IntVector.fromArray(this,a,offset) or an equivalent fromArray method, on the vector type corresponding to this species.
        Parameters:
        a - an array of the ETYPE for this species
        offset - the index of the first lane value to load
        Returns:
        a vector of the given species filled from the array
        Throws:
        IndexOutOfBoundsException - if offset+N < 0 or offset+N >= a.length for any lane N in the vector
        See Also:
        IntVector.fromArray(VectorSpecies,int[],int), FloatVector.fromArray(VectorSpecies,float[],int)

      • fromValues

        Vector<E> fromValues​(long... values)
        Returns a vector of this species where lane elements are initialized from the given sequence of longs. The long values must all be representable by the ETYPE of this species. Equivalent to IntVector.fromArray(this,a,offset) or an equivalent fromArray method, on the vector type corresponding to this species, after the values are copied (without loss of value or precision) to an appropriately typed array.
        Parameters:
        values - an array of values to load into the vector
        Returns:
        a vector of the given species filled from the array
        Throws:
        IllegalArgumentException - if values.length != species.length() or if any of the values cannot be represented by the ETYPE of this species
        See Also:
        IntVector.fromArray(VectorSpecies,int[],int), FloatVector.fromArray(VectorSpecies,float[],int), checkValue(long)

      • fromByteArray

        Vector<E> fromByteArray​(byte[] a,
                        int offset)
        Returns a vector of this species where lane elements are initialized from the given byte array at the given offset. Equivalent to IntVector.fromByteArray(this,a,offset) or an equivalent fromByteArray method, on the vector type corresponding to this species.
        Parameters:
        a - a byte array
        offset - the index of the first byte to load
        Returns:
        a vector of the given species filled from the byte array
        Throws:
        IndexOutOfBoundsException - if offset+N*ESIZE < 0 or offset+(N+1)*ESIZE > a.length for any lane N in the vector
        See Also:
        IntVector.fromByteArray(VectorSpecies,byte[],int), FloatVector.fromByteArray(VectorSpecies,byte[],int)

      • loadMask

        VectorMask<E> loadMask​(boolean[] bits,
                       int offset)
        Returns a mask of this species where lane elements are initialized from the given array at the given offset. Equivalent to VectorMask.fromArray(this,a,offset).
        Parameters:
        bits - the boolean array
        offset - the offset into the array
        Returns:
        the mask loaded from the boolean array
        Throws:
        IndexOutOfBoundsException - if offset+N < 0 or offset+N >= a.length for any lane N in the vector mask
        See Also:
        VectorMask.fromArray(VectorSpecies,boolean[],int)

      • maskAll

        VectorMask<E> maskAll​(boolean bit)
        Returns a mask of this species, where each lane is set or unset according to given single boolean, which is broadcast to all lanes.
        Parameters:
        bit - the given mask bit to be replicated
        Returns:
        a mask where each lane is set or unset according to the given bit
        See Also:
        Vector.maskAll(boolean)

      • broadcast

        Vector<E> broadcast​(long e)
        Returns a vector of the given species where all lane elements are set to the primitive value e.

        This method returns the value of this expression: EVector.broadcast(this, (ETYPE)e), where EVector is the vector class specific to the the ETYPE of this species. The long value must be accurately representable by ETYPE, so that e==(long)(ETYPE)e.

        Parameters:
        e - the value to broadcast
        Returns:
        a vector where all lane elements are set to the primitive value e
        Throws:
        IllegalArgumentException - if the given long value cannot be represented by the vector species ETYPE
        See Also:
        Vector.broadcast(long), checkValue(long)

      • checkValue

        long checkValue​(long e)
        Checks that this species can represent the given element value, and returns the value unchanged. The long value must be accurately representable by the ETYPE of the vector species, so that e==(long)(ETYPE)e. The effect is similar to this pseudocode: e == (long)(ETYPE)e ? e : throw new IllegalArgumentException().
        Parameters:
        e - the value to be checked
        Returns:
        e
        Throws:
        IllegalArgumentException - if the given long value cannot be represented by the vector species ETYPE
        See Also:
        broadcast(long)

      • shuffleFromValues

        VectorShuffle<E> shuffleFromValues​(int... sourceIndexes)
        Creates a shuffle for this species from a series of source indexes.

        For each shuffle lane, where N is the shuffle lane index, the Nth index value is validated against the species VLENGTH, and (if invalid) is partially wrapped to an exceptional index in the range [-VLENGTH..-1].

        Parameters:
        sourceIndexes - the source indexes which the shuffle will draw from
        Returns:
        a shuffle where each lane's source index is set to the given int value, partially wrapped if exceptional
        Throws:
        IndexOutOfBoundsException - if sourceIndexes.length != VLENGTH
        See Also:
        VectorShuffle.fromValues(VectorSpecies,int...)

      • shuffleFromArray

        VectorShuffle<E> shuffleFromArray​(int[] sourceIndexes,
                                  int offset)
        Creates a shuffle for this species from an int array starting at an offset.

        For each shuffle lane, where N is the shuffle lane index, the array element at index i + N is validated against the species VLENGTH, and (if invalid) is partially wrapped to an exceptional index in the range [-VLENGTH..-1].

        Parameters:
        sourceIndexes - the source indexes which the shuffle will draw from
        offset - the offset into the array
        Returns:
        a shuffle where each lane's source index is set to the given int value, partially wrapped if exceptional
        Throws:
        IndexOutOfBoundsException - if offset < 0, or offset > sourceIndexes.length - VLENGTH
        See Also:
        VectorShuffle.fromArray(VectorSpecies,int[],int)

      • shuffleFromOp

        VectorShuffle<E> shuffleFromOp​(IntUnaryOperator fn)
        Creates a shuffle for this species from the successive values of an operator applied to the range [0..VLENGTH-1].

        For each shuffle lane, where N is the shuffle lane index, the Nth index value is validated against the species VLENGTH, and (if invalid) is partially wrapped to an exceptional index in the range [-VLENGTH..-1].

        Care should be taken to ensure VectorShuffle values produced from this method are consumed as constants to ensure optimal generation of code. For example, shuffle values can be held in static final fields or loop-invariant local variables.

        This method behaves as if a shuffle is created from an array of mapped indexes as follows: 

        
   int[] a = new int[VLENGTH];
   for (int i = 0; i < a.length; i++) {
       a[i] = fn.applyAsInt(i);
   }
   return VectorShuffle.fromArray(this, a, 0);
        Parameters:
        fn - the lane index mapping function
        Returns:
        a shuffle of mapped indexes
        See Also:
        VectorShuffle.fromOp(VectorSpecies,IntUnaryOperator)

      • iotaShuffle

        VectorShuffle<E> iotaShuffle​(int start,
                             int step,
                             boolean wrap)
        Creates a shuffle using source indexes set to sequential values starting from start and stepping by the given step. If wrap is true, also reduce each index, as if by wrapIndex, to the valid range [0..VLENGTH-1].

        This method returns the value of the expression shuffleFromOp(i -> R(start + i * step)), where R is wrapIndex if wrap is true, and is the identity function otherwise.

        API Note:
        The wrap parameter should be set to true if invalid source indexes should be wrapped. Otherwise, setting it to false allows invalid source indexes to be range-checked by later operations such as unary rearrange.
        Parameters:
        start - the starting value of the source index sequence, typically 0
        step - the difference between adjacent source indexes, typically 1
        wrap - whether to wrap resulting indexes modulo VLENGTH
        Returns:
        a shuffle of sequential lane indexes
        See Also:
        VectorShuffle.iota(VectorSpecies,int,int,boolean)

      • toString

        String toString()
        Returns a string of the form "Species[ETYPE, VLENGTH, SHAPE]", where ETYPE is the primitive lane type, VLENGTH is the vector lane count associated with the species, and SHAPE is the vector shape associated with the species.
        Overrides:
        toString in class Object
        Returns:
        a string of the form "Species[ETYPE, VLENGTH, SHAPE]"

      • equals

        boolean equals​(Object obj)
        Indicates whether this species is identical to some other object. Two species are identical only if they have the same shape and same element type.
        Overrides:
        equals in class Object
        Parameters:
        obj - the reference object with which to compare.
        Returns:
        whether this species is identical to some other object
        See Also:
        Object.hashCode(), HashMap