1.2.1. Bfloat16 Arithmetic Functions

[Bfloat16 Precision Intrinsics]

To use these functions include the header file cuda_bf16.h in your program.

Functions

__device__ ​ __nv_bfloat162 __h2div ( const __nv_bfloat162 a, const __nv_bfloat162 b )
Performs nv_bfloat162 vector division in round-to-nearest-even mode.
__device__ ​ __nv_bfloat16 __habs ( const __nv_bfloat16 a )
Calculates the absolute value of input nv_bfloat16 number and returns the result.
__device__ ​ __nv_bfloat16 __hadd ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 addition in round-to-nearest-even mode.
__device__ ​ __nv_bfloat16 __hadd_sat ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 addition in round-to-nearest-even mode, with saturation to [0.0, 1.0].
__device__ ​ __nv_bfloat16 __hdiv ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 division in round-to-nearest-even mode.
__device__ ​ __nv_bfloat16 __hfma ( const __nv_bfloat16 a, const __nv_bfloat16 b, const __nv_bfloat16 c )
Performs nv_bfloat16 fused multiply-add in round-to-nearest-even mode.
__device__ ​ __nv_bfloat16 __hfma_relu ( const __nv_bfloat16 a, const __nv_bfloat16 b, const __nv_bfloat16 c )
Performs nv_bfloat16 fused multiply-add in round-to-nearest-even mode with relu saturation.
__device__ ​ __nv_bfloat16 __hfma_sat ( const __nv_bfloat16 a, const __nv_bfloat16 b, const __nv_bfloat16 c )
Performs nv_bfloat16 fused multiply-add in round-to-nearest-even mode, with saturation to [0.0, 1.0].
__device__ ​ __nv_bfloat16 __hmul ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 multiplication in round-to-nearest-even mode.
__device__ ​ __nv_bfloat16 __hmul_sat ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 multiplication in round-to-nearest-even mode, with saturation to [0.0, 1.0].
__device__ ​ __nv_bfloat16 __hneg ( const __nv_bfloat16 a )
Negates input nv_bfloat16 number and returns the result.
__device__ ​ __nv_bfloat16 __hsub ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 subtraction in round-to-nearest-even mode.
__device__ ​ __nv_bfloat16 __hsub_sat ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 subtraction in round-to-nearest-even mode, with saturation to [0.0, 1.0].

Functions

__device__ ​ __nv_bfloat162 __h2div ( const __nv_bfloat162 a, const __nv_bfloat162 b )
Performs nv_bfloat162 vector division in round-to-nearest-even mode.
Description

Divides nv_bfloat162 input vector a by input vector b in round-to-nearest mode.

__device__ ​ __nv_bfloat16 __habs ( const __nv_bfloat16 a )
Calculates the absolute value of input nv_bfloat16 number and returns the result.
Parameters
a
- nv_bfloat16. Is only being read.
Returns

nv_bfloat16

  • The

    absolute value of a.

Description

Calculates the absolute value of input nv_bfloat16 number and returns the result.

__device__ ​ __nv_bfloat16 __hadd ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 addition in round-to-nearest-even mode.
Description

Performs nv_bfloat16 addition of inputs a and b, in round-to-nearest-even mode.

__device__ ​ __nv_bfloat16 __hadd_sat ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 addition in round-to-nearest-even mode, with saturation to [0.0, 1.0].
Parameters
a
- nv_bfloat16. Is only being read.
b
- nv_bfloat16. Is only being read.
Returns

nv_bfloat16

  • The

    sum of a and b, with respect to saturation.

Description

Performs nv_bfloat16 add of inputs a and b, in round-to-nearest-even mode, and clamps the result to range [0.0, 1.0]. NaN results are flushed to +0.0.

__device__ ​ __nv_bfloat16 __hdiv ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 division in round-to-nearest-even mode.
Description

Divides nv_bfloat16 input a by input b in round-to-nearest mode.

__device__ ​ __nv_bfloat16 __hfma ( const __nv_bfloat16 a, const __nv_bfloat16 b, const __nv_bfloat16 c )
Performs nv_bfloat16 fused multiply-add in round-to-nearest-even mode.
Description

Performs nv_bfloat16 multiply on inputs a and b, then performs a nv_bfloat16 add of the result with c, rounding the result once in round-to-nearest-even mode.

__device__ ​ __nv_bfloat16 __hfma_relu ( const __nv_bfloat16 a, const __nv_bfloat16 b, const __nv_bfloat16 c )
Performs nv_bfloat16 fused multiply-add in round-to-nearest-even mode with relu saturation.
Parameters
a
- nv_bfloat16. Is only being read.
b
- nv_bfloat16. Is only being read.
c
- nv_bfloat16. Is only being read.
Returns

nv_bfloat16

  • The

    result of fused multiply-add operation on a, b, and c with relu saturation.

Description

Performs nv_bfloat16 multiply on inputs a and b, then performs a nv_bfloat16 add of the result with c, rounding the result once in round-to-nearest-even mode. Then negative result is clamped to 0. NaN result is converted to canonical NaN.

__device__ ​ __nv_bfloat16 __hfma_sat ( const __nv_bfloat16 a, const __nv_bfloat16 b, const __nv_bfloat16 c )
Performs nv_bfloat16 fused multiply-add in round-to-nearest-even mode, with saturation to [0.0, 1.0].
Parameters
a
- nv_bfloat16. Is only being read.
b
- nv_bfloat16. Is only being read.
c
- nv_bfloat16. Is only being read.
Returns

nv_bfloat16

  • The

    result of fused multiply-add operation on a, b, and c, with respect to saturation.

Description

Performs nv_bfloat16 multiply on inputs a and b, then performs a nv_bfloat16 add of the result with c, rounding the result once in round-to-nearest-even mode, and clamps the result to range [0.0, 1.0]. NaN results are flushed to +0.0.

__device__ ​ __nv_bfloat16 __hmul ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 multiplication in round-to-nearest-even mode.
Description

Performs nv_bfloat16 multiplication of inputs a and b, in round-to-nearest mode.

__device__ ​ __nv_bfloat16 __hmul_sat ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 multiplication in round-to-nearest-even mode, with saturation to [0.0, 1.0].
Parameters
a
- nv_bfloat16. Is only being read.
b
- nv_bfloat16. Is only being read.
Returns

nv_bfloat16

  • The

    result of multiplying a and b, with respect to saturation.

Description

Performs nv_bfloat16 multiplication of inputs a and b, in round-to-nearest mode, and clamps the result to range [0.0, 1.0]. NaN results are flushed to +0.0.

__device__ ​ __nv_bfloat16 __hneg ( const __nv_bfloat16 a )
Negates input nv_bfloat16 number and returns the result.
Description

Negates input nv_bfloat16 number and returns the result.

__device__ ​ __nv_bfloat16 __hsub ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 subtraction in round-to-nearest-even mode.
Description

Subtracts nv_bfloat16 input b from input a in round-to-nearest mode.

__device__ ​ __nv_bfloat16 __hsub_sat ( const __nv_bfloat16 a, const __nv_bfloat16 b )
Performs nv_bfloat16 subtraction in round-to-nearest-even mode, with saturation to [0.0, 1.0].
Parameters
a
- nv_bfloat16. Is only being read.
b
- nv_bfloat16. Is only being read.
Returns

nv_bfloat16

  • The

    result of subtraction of b from a, with respect to saturation.

Description

Subtracts nv_bfloat16 input b from input a in round-to-nearest mode, and clamps the result to range [0.0, 1.0]. NaN results are flushed to +0.0.