1.8 KiB
Executable File
1.8 KiB
Executable File
NEG — Two's Complement Negation
Description
Replaces the value of operand (the destination operand) with its two's complement. This operation is equivalent to subtracting the operand from 0. The destination operand is located in a general-purpose register or a memory location.
Instruction
| Opcode | Assembly | Op/En | Modern Mode | Legacy Mode | Description |
|---|---|---|---|---|---|
| F6 /3 | NEG r/m8 | M | Valid | Valid | Two's complement negate r/m8. |
| REX + F6 /3 | NEG r/m8* | M | Valid | N.E. | Two's complement negate r/m8. |
| F7 /3 | NEG r/m16 | M | Valid | Valid | Two's complement negate r/m16. |
| F7 /3 | NEG r/m32 | M | Valid | Valid | Two's complement negate r/m32. |
| REX.W + F7 /3 | NEG r/m64 | M | Valid | N.E. | Two's complement negate r/m64. |
- In 64-bit mode, r/m8 can not be encoded to access the following byte registers if a REX prefix is used: AH, BH, CH, DH.
Information
This instruction can be used with a LOCK prefix to allow the instruction to be executed atomically.
In 64-bit mode, the instruction’s default operation size is 32 bits. Using a REX prefix in the form of REX.R permits access to additional registers (R8-R15). Using a REX prefix in the form of REX.W promotes operation to 64 bits. See the summary chart at the beginning of this section for encoding data and limits.