vloadn

Read vectors from a pointer to memory.

gentypen vloadn ( size_t  offset ,
  const __global gentype  *p)
gentypen vloadn ( size_t  offset ,
  const __local gentype  *p )
gentypen vloadn ( size_t  offset ,
  const __constant gentype  *p )
gentypen vloadn ( size_t  offset ,
  const __private gentype  *p )

Description

Return sizeof (gentypen) bytes of data read from address (p + (offset * n)).

The address computed as (p + (offset * n)) must be 8-bit aligned if gentype is char or uchar; 16-bit aligned if gentype is short or ushort; 32-bit aligned if gentype is int, uint, or float; 64-bit aligned if gentype is long or ulong.

If the double extension is enabled, then in addition to the above the address must be 64-bit aligned if gentype is longn, ulongn, or doublen.

If the half extension is enabled, the address computed as (p + (offset * n)) must be 16-bit aligned.

Notes

Vector Data Load and Store Functions allow you to read and write vector types from a pointer to memory.

The results of vector data load and store functions are undefined if the address being read from or written to is not correctly aligned. The pointer argument p can be a pointer to __global, __local, or __private memory for store functions. The pointer argument p can be a pointer to __global, __local, __constant or __private memory for load functions.

The generic type gentype is used to indicate the built-in data types char, uchar, short, ushort, int, uint, long, ulong, or float.

The generic type name gentypen represents n-element vectors of gentype elements. The suffix n is also used in the function names (i.e. vloadn, vstoren, etc.), where n = 2, 3, 4, 8, or 16.

This function may be extended with the cl_khr_fp64 extension to include versions that read from or write to double scalar or vector values.

The generic type gentype is extended to include double. The generic type gentypen is extended to include double2, double3, double4, double8, and double16.

The vstore_half, vstore_halfn, and vstorea_halfn functions are extended to allow a double precision scalar or vector value to be written to memory as half values.

This function may be extended to include versions that read from or write to half scalar or vector values. We use the type name halfn to represent n-element vectors of half elements when enabled by the cl_khr_fp16 extension. The generic type gentypen is extended to include half, half2, half3, half4, half8, and half16.

vload3 and vload_half3 read x, y, z components from address (p + (offset * 3)) into a 3-component vector. vstore3, and vstore_half3 write x, y, z components from a 3-component vector to address (p + (offset * 3)).

In addition vloada_half3 reads x, y, z components from address (p + (offset * 4)) into a 3- component vector and vstorea_half3 writes x, y, z components from a 3-component vector to address (p + (offset * 4)).

Specification

OpenCL Specification

Also see

Vector Data Load and Store Functions

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