Online HelpPC 2.10 Quick Reference Utility Copyright 1991 David Jurgens
MUL - Unsigned Multiply
Usage: MUL src
Modifies flags: CF OF (AF,PF,SF,ZF undefined)
Unsigned multiply of the accumulator by the source. If "src" is
a byte value, then AL is used as the other multiplicand and the
result is placed in AX. If "src" is a word value, then AX is
multiplied by "src" and DX:AX receives the result. If "src" is
a double word value, then EAX is multiplied by "src" and EDX:EAX
receives the result. The 386+ uses an early out algorithm which
makes multiplying any size value in EAX as fast as in the 8 or 16
bit registers.
Clocks Size
Operands 808x 286 386 486 Bytes
reg8 70-77 13 9-14 13-18 2
reg16 118-113 21 9-22 13-26 2
reg32 - - 9-38 13-42 2-4
mem8 (76-83)+EA 16 12-17 13-18 2-4
mem16 (124-139)+EA 24 12-25 13-26 2-4
mem32 - - 12-21 13-42 2-4
- see Instruction Timing IMUL
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