Signed multiplication of accumulator by “src” with result placed in the accumulator.
Other variations of this instruction allow specification of source and destination registers as well as a third immediate factor.
Usage:
IMUL src IMUL src,immed ; (286+ only) IMUL dest,src,immed8 ; (286+ only) IMUL dest,src ; (386+ only)
Modifies flags:
CF OF
| Clocks | Size | |||||
|---|---|---|---|---|---|---|
| Operands | 808x | 286 | 386 | 486 | Bytes | |
| reg8 | 80-98 | 13 | 9-14 | 13-18 | 2 | |
| reg16 | 128-154 | 21 | 9-22 | 13-26 | 2 | |
| reg32 | - | - | 9-38 | 13-41 | 2 | |
| mem8 | 86-104 | 16 | 12-17 | 13-18 | 2-4 | |
| mem16 | 134-160 | 24 | 12-25 | 13-26 | 2-4 | |
| mem32 | - | - | 12-21 | 13-42 | 2-4 | |
| reg16,reg16 | - | - | 9-22 | 13-26 | 3-5 | |
| reg32,reg32 | - | - | 9-38 | 13-42 | 3-5 | |
| reg16,mem16 | - | - | 12-25 | 13-26 | 3-5 | |
| reg32,mem32 | - | - | 12-41 | 13-42 | 3-5 | |
| reg16,immed | - | 21 | 9-22 | 13-26 | 3 | |
| reg32,immed | - | 21 | 9-38 | 13-42 | 3-6 | |
| reg16,reg16,immed | - | 2 | 9-22 | 13-26 | 3-6 | |
| reg32,reg32,immed | - | 21 | 9-38 | 13-42 | 3-6 | |
| reg16,mem16,immed | - | 24 | 12-25 | 13-26 | 3-6 | |
| reg32,mem32,immed | - | 24 | 12-41 | 13-42 | 3-6 | |