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VFMSUB213SD

Performs a fused multiply-subtract operation on scalar double-precision floating-point values. It computes the result of (a * b) - c using the specified operands and stores the result in the destination.

The table after the description covers what the source and destinations can be.

DO NOT support LOCK

This instruction is only available when the AVX-512 foundation instructions are supported. It requires the processor to be in 64-bit mode or a compatibility mode that supports the AVX-512 instruction set.

The operation is performed with a single rounding step at the end, which avoids intermediate rounding errors associated with separate multiply and subtract instructions. Ensure the destination register is not used as a source if the result must be preserved, as it is overwritten. The instruction supports masking; if a mask is used and a bit is 0, the corresponding element in the destination register remains unchanged (merging masking) or is zeroed (zeroing masking).