4. Half Precision Intrinsics
This section describes half precision intrinsic functions.
To use these functions, include the header file cuda_fp16.h in your program. All of the functions defined here are available in device code. Some of the functions are also available to host compilers, please refer to respective functions’ documentation for details.
NOTE: Aggressive floating-point optimizations performed by host or device compilers may affect numeric behavior of the functions implemented in this header.
The following macros are available to help users selectively enable/disable various definitions present in the header file:
CUDA_NO_HALF- If defined, this macro will prevent the definition of additional type aliases in the global namespace, helping to avoid potential conflicts with symbols defined in the user program.__CUDA_NO_HALF_CONVERSIONS__- If defined, this macro will prevent the use of the C++ type conversions (converting constructors and conversion operators) that are common for built-in floating-point types, but may be undesirable forhalfwhich is essentially a user-defined type.__CUDA_NO_HALF_OPERATORS__and__CUDA_NO_HALF2_OPERATORS__- If defined, these macros will prevent the inadvertent use of usual arithmetic and comparison operators. This enforces the storage-only type semantics and prevents C++ style computations onhalfandhalf2types.
Groups
- Half Arithmetic Constants
To use these constants, include the header file
cuda_fp16.hin your program.- Half Arithmetic Functions
To use these functions, include the header file
cuda_fp16.hin your program.- Half Comparison Functions
To use these functions, include the header file
cuda_fp16.hin your program.- Half Math Functions
To use these functions, include the header file
cuda_fp16.hin your program.- Half Precision Conversion and Data Movement
To use these functions, include the header file
cuda_fp16.hin your program.- Half2 Arithmetic Functions
To use these functions, include the header file
cuda_fp16.hin your program.- Half2 Comparison Functions
To use these functions, include the header file
cuda_fp16.hin your program.- Half2 Math Functions
To use these functions, include the header file
cuda_fp16.hin your program.
Structs
- __half
__half data type
- __half2
__half2 data type
- __half2_raw
__half2_raw data type
- __half_raw
__half_raw data type
Typedefs
- __nv_half
This datatype is an
__nv_prefixed alias.- __nv_half2
This datatype is an
__nv_prefixed alias.- __nv_half2_raw
This datatype is an
__nv_prefixed alias.- __nv_half_raw
This datatype is an
__nv_prefixed alias.- half
This datatype is meant to be the first-class or fundamental implementation of the half-precision numbers format.
- half2
This datatype is meant to be the first-class or fundamental implementation of type for pairs of half-precision numbers.
- nv_half
This datatype is an
nv_prefixed alias.- nv_half2
This datatype is an
nv_prefixed alias.
4.9. Typedefs
-
typedef __half2_raw __nv_half2_raw
This datatype is an
__nv_prefixed alias.
-
typedef __half_raw __nv_half_raw
This datatype is an
__nv_prefixed alias.
-
typedef __half half
This datatype is meant to be the first-class or fundamental implementation of the half-precision numbers format.
Should be implemented in the compiler in the future. Current implementation is a simple typedef to a respective user-level type with underscores.