prefetch

Prefetch bytes into the global cache.

void prefetch ( const __global gentype *p,
  size_t num_gentypes)

Description

prefetch prefetches num_gentypes * sizeof(gentype) bytes into the global cache. The prefetch instruction is applied to a work-item in a work-group and does not affect the functional behavior of the kernel.

The generic type name gentype indicates the built-in data types char, char{2|3|4|8|16}, uchar, uchar{2|3|4|8|16}, short, short{2|3|4|8|16}, ushort, ushort{2|3|4|8|16}, int, int{2|3|4|8|16}, uint, uint{2|3|4|8|16}, long, long{2|3|4|8|16}, ulong, ulong{2|3|4|8|16}, float, float{2|3|4|8|16}, or double, double{2|3|4|8|16} as the type for the arguments unless otherwise stated.

When extended by the cl_khr_fp16 extension, the generic type gentypen is extended to include half, half2, half3, half4, half8, and half16.

The kernel must wait for the completion of all async copies using the wait_group_events built-in function before exiting; otherwise the behavior is undefined.

Specification

OpenCL Specification

Also see

Async Copy and Prefetch Functions

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