1013 B
1013 B
| Opcode | Instruction | Op/En | 64-Bit Mode | Compat/Leg Mode | Description |
|---|---|---|---|---|---|
| FE /1 | DEC r/m8 | M | Valid | Valid | Decrement r/m8 by 1. |
| REX + FE /1 | DEC r/m8* | M | Valid | N.E. | Decrement r/m8 by 1. |
| FF /1 | DEC r/m16 | M | Valid | Valid | Decrement r/m16 by 1. |
| FF /1 | DEC r/m32 | M | Valid | Valid | Decrement r/m32 by 1. |
| REX.W + FF /1 | DEC r/m64 | M | Valid | N.E. | Decrement r/m64 by 1. |
| 48+rw | DEC r16 | O | N.E. | Valid | Decrement r16 by 1. |
| 48+rd | DEC r32 | O | N.E. | Valid | Decrement r32 by 1. |
- In64-bit mode, r/m8 cannot been coded to access the following byte registers if a REX prefix is used: AH, BH, CH, DH.