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VFMSUB132PD

Performs a fused multiply-subtract operation on packed double-precision floating-point values. The instruction computes the result of (a * b) - c for each corresponding pair of elements in the source operands, where the operands are mapped as follows: the first source is multiplied by the second source, and the third source is subtracted from the product.

The table below covers what the source and destinations can be.

DO NOT support LOCK

This instruction is only available when the processor is operating in 64-bit mode or 32-bit mode with AVX enabled. It requires the VEX encoding scheme; using it in compatibility mode without AVX support will result in an invalid opcode exception.

The destination register is used as one of the operands (the third source operand c) and is overwritten by the result. To preserve the original value of the third operand, it MUST be copied to a temporary register before execution. This instruction performs a single rounding step at the end of the entire operation, preventing the intermediate precision loss associated with separate multiply and subtract instructions.