Description

The list of supported atomic type names are:

  • atomic_int

  • atomic_uint

  • atomic_long [1]

  • atomic_ulong [1]

  • atomic_float

  • atomic_double [2]

  • atomic_intptr_t [3]

  • atomic_uintptr_t [3]

  • atomic_size_t [3]

  • atomic_ptrdiff_t [3]

Arguments to a kernel can be declared to be a pointer to the above atomic types or the atomic_flag type.

The representation of atomic integer, floating-point and pointer types have the same size as their corresponding regular types. The atomic_flag type must be implemented as a 32-bit integer.

See Also

atomicFunctions

Document Notes

For more information, see the OpenCL C Specification

This page is extracted from the OpenCL C Specification. Fixes and changes should be made to the Specification, not directly.

Copyright

Copyright 2014-2025 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0

1. The atomic_long and atomic_ulong types are supported if the cl_khr_int64_base_atomics and cl_khr_int64_extended_atomics extensions are supported and have been enabled. If this is the case then an OpenCL C 3.0 compiler must also define the __opencl_c_int64 feature.
2. The atomic_double type is only supported if double precision is supported and the cl_khr_int64_base_atomics and cl_khr_int64_extended_atomics extensions are supported and have been enabled. If this is the case then an OpenCL C 3.0 compiler must also define the __opencl_c_fp64 feature.
3. If the device address space is 64-bits, the data types atomic_intptr_t, atomic_uintptr_t, atomic_size_t and atomic_ptrdiff_t are supported if the cl_khr_int64_base_atomics and cl_khr_int64_extended_atomics extensions are supported and have been enabled.