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VFNMSUB213PD

Computes the fused multiply-subtract result for two pairs of double-precision floating-point values. It calculates $(a \times b) - c$ and $(d \times e) - f$ using the formula $dest = (src1 \times src2) - src3$, where $src1$ and $src2$ are the multipliers and $src3$ is the subtrahend.

The following table covers what the source and destinations can be:

DO NOT support LOCK

This instruction SHALL be executed in 64-bit mode or compatibility mode. It REQUIRES the AVX support to be enabled in the processor.

The operation is performed with a single rounding step at the end; intermediate products are not rounded, which prevents cumulative rounding errors and avoids #O and #U for the intermediate product. If the result cannot be represented in the destination format, it MAY trigger #O, #U, or #P. If any operand is a signaling NaN, it SHALL trigger #I.