asm/reference

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SUBSD



Subtracts a scalar-double precision floating-point value from another scalar-double precision floating-point value and stores the result in the destination operand.

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

source destination(s)
r64 r64
m8 r64
r64 m8

DO NOT support LOCK

This instruction is available in 64-bit mode and compatibility mode. It is not supported in 32-bit mode.

The instruction performs the operation according to IEEE 754 standards. It affects the MXCSR register by updating status flags such as #P, #O, #U, and #D based on the result of the subtraction. Ensure that the destination register is an XMM register to avoid invalid opcode exceptions.