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VFMSUB231SH
Performs a fused multiply-subtract operation on signed short floating-point values. The instruction computes the result of (a * b) - c, where the operands are treated as 16-bit floating-point numbers (half-precision), and stores the result in the destination.
The following table covers what the source and destinations can be:
| source | destination(s) |
|---|---|
| reg | reg |
DO NOT support LOCK
This instruction is only available when the processor supports the AVX-512 FP16 extension. It requires the processor to be in 64-bit mode.
The operation is performed according to IEEE 754-2008 standards for half-precision floating-point arithmetic. The fused multiply-subtract operation is performed with infinite precision before rounding the final result to the nearest representable f16 value, which avoids intermediate rounding errors.
The instruction may trigger the following exceptions:
- #D: If an operand is a denormalized number.
- #O: If the result exceeds the maximum representable value of f16.
- #U: If the result is smaller than the minimum representable positive f16 value.
- #P: If the result is not exactly representable and requires rounding.