shuffle - Constructs a permutation of elements from one (or two) input vectors.

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       The shuffle and shuffle2 built-in functions construct a permutation of elements from one or two input
       vectors respectively that are of the same type, returning a vector with the same element type as the
       input and length that is the same as the shuffle mask. The size of each element in the mask must match
       the size of each element in the result. For shuffle, only the ilogb(3clc)(2m-1) least significant bits of
       each mask element are considered. For shuffle2, only the ilogb(3clc)(2m-1)+1 least significant bits of
       each mask element are considered. Other bits in the mask shall be ignored.

       The elements of the input vectors are numbered from left to right across one or both of the vectors. For
       this purpose, the number of elements in a vector is given by vec_step(3clc)(gentypem). The shuffle mask
       operand specifies, for each element of the result vector, which element of the one or two input vectors
       the result element gets.

       We use the generic type name gentypen (or gentypem) to indicate the built-in data types char{2|4|8|16},
       uchar{2|4|8|16}, short{2|4|8|16}, ushort{2|4|8|16}, int{2|4|8|16}, uint{2|4|8|16}, long{2|4|8|16},
       ulong{2|4|8|16}, or float{2|4|8|16} as the type for the arguments unless otherwise stated. We use the
       generic name ugentypen to indicate the built-in unsigned integer data types. If the double is supported,
       then gentypen (or gentypem) also indicate the built-in data types double{2|4|8|16}.

       The generic type name gentypen (or gentypem) may indicate the data type half{2|4|8|16} if the
       cl_khr_fp16(3clc) extension is supported.

   Example
       uint4 mask = (uint4)(3, 2, 1, 0); float4 a; float4 r =
       shuffle(a, mask); // r.s0123 = a.wzyx

       uint8 mask = (uint8)(0, 1, 2, 3, 4, 5, 6, 7);

       float4 a, b; float8 r = shuffle2(a, b, mask); // r.s0123
       = a.xyzw // r.s4567 = b.xyzw

       uint4 mask; float8 a; float4 b; b = shuffle(a, mask);

       Examples that are not valid are:
       uint8 mask; short16 a; short8 b; b = shuffle(a, mask);

       shuffle - Constructs a permutation of elements from one (or two) input vectors.

       gentypenshuffle(gentypemx,ugentypenmask);gentypenshuffle2(gentypemx,gentypemy,ugentypenmask);

        1. OpenCL Specification
           page 282, section 6.12.12 Miscellaneous Vector Functions

The Khronos Group                                  11/18/2024                            SHUFFLE,SHUFFLE2(3clc)

miscVectorFunctions(3clc)

OpenCLSpecification[1]