Multiply-adds negated scalar single-precision floating-point values of three float32 vectors. The corresponding FMA instruction is VFNMADD<XXX>SS, where XXX could be 132, 213, or 231.
extern __m128 _mm_fnmadd_ss(__m128 a, __m128 b, __m128 c); |
a |
float64 vector used for the operation |
b |
float64 vector also used for the operation |
c |
float64 vector also used for the operation |
Performs a set of SIMD negated multiply-add computation on scalar single-precision floating-point values using three source vectors/operands, a, b, and c. Corresponding values in two operands, a and b, are multiplied and the negated infinite precision intermediate results are added to the values in the third operand, c, after which the final results are rounded to the nearest float32 values.
The compiler defaults to using the VFNMADD213SS instruction and uses the other forms VFNMADD132SS or VFNMADD231SS only if a low level optimization decides it as useful or necessary. For example, the compiler could change the default if it finds that another instruction form saves a register or eliminates a move.
Result of the negated multiply-add operation.
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