fma

Description

Returns the correctly rounded floating-point representation of the sum of c with the infinitely precise product of a and b. Rounding of intermediate products shall not occur. Edge case behavior is per the IEEE 754-2008 standard.

Notes

The vector versions of the math functions operate component-wise. The description is per-component.

The built-in math functions are not affected by the prevailing rounding mode in the calling environment, and always return the same value as they would if called with the round to nearest even rounding mode.

The built-in math functions take scalar or vector arguments. The generic type name gentype is used to indicate that the function can take float, float2, float3, float4, float8, or float16 as the type for the arguments. For any specific use of these function, the actual type has to be the same for all arguments and the return type.

If extended with cl_khr_fp64, generic type name gentype may indicate double and double{2|3|4|8|16} as arguments and return values. If extended with cl_khr_fp16, generic type name gentype may indicate half and half{2|3|4|8|16} as arguments and return values.

The FP_FAST_FMA_HALF macro indicates whether the fma() family of functions are fast compared with direct code for half precision floating-point. If defined, the FP_FAST_FMA_HALF macro shall indicate that the fma() function generally executes about as fast as, or faster than, a multiply and an add of half operands

Specification

OpenCL Specification

Also see

Math Functions, Floating-Point Macros and Pragma,

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