X86-assembly/Instructions/imul

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X86-assembly

Instructions

imul

Description

Signed multiplication of 2 operands. If only 1 register provided, multiplies it by eax.

Syntax

IMUL r/m32

EDX:EAX = EAX * r/m doubleword

IMUL r32,r/m32

doubleword register = doubleword register * r/m doubleword

Examples

mov     eax, 9          ; eax = 9
mov     edx, 66666667h  ; edx = 0x66666667
imul    edx             ; edx:eax = 0x66666667 * 9 = 0x39999999f
                        ; => edx = 0x3
                        ; => eax = 0x9999999f