04 ib         ADD AL, imm8                 Add imm8 to AL

05 iw         ADD AX, imm16                 Add imm16 to AX

05 id         ADD EAX, imm32                 Add imm32 to EAX

80 /0 ib         ADD r/m8,imm8                 Add imm8 to r/m8

81 /0 iw         ADD r/m16,imm16                 Add imm16 to r/m16

81 /0 id         ADD r/m32,imm32                 Add imm32 to r/m32

83 /0 ib         ADD r/m16,imm8                 Add sign-extended imm8 to r/m16

83 /0 ib         ADD r/m32,imm8                 Add sign-extended imm8 to r/m32

00 / r         ADD r/m8,r8                 Add r8 to r/m8

01 / r         ADD r/m16,r16                 Add r16 to r/m16

01 / r         ADD r/m32,r32                 Add r32 to r/m32

02 / r         ADD r8,r/m8                 Add r/m8 to r8

03 / r         ADD r16,r/m16                 Add r/m16 to r16

03 / r         ADD r32,r/m32                 Add r/m32 to r32


Description

Adds the first operand (destination operand) and the second operand (source operand) and stores the result in the destination operand. The destination operand can be a register or a memory location; the source operand can be an immediate, a register, or a memory location. (However, two memory operands cannot be used in one instruction.) When an immediate value is used as an operand, it is sign-extended to the length of the destination operand format.


The ADD instruction does not distinguish between signed or unsigned operands. Instead, the processor evaluates the result for both data types and sets the OF and CF flags to indicate a carry in the signed or unsigned result, respectively. The SF flag indicates the sign of the signed result.


Operands        Bytes                Clocks

reg, reg             2                       1   UV

mem, reg          2+d(0,2)          3   UV

reg, mem          2+d(0,2)          2   UV

reg, imm          2+i(1,2)           1   UV

mem, imm          2+d(0,2)+i(1,2)          3   UV*

acc, imm          1+i(1,2)           1   UV


* = not pairable if there is a displacement and immediate

                       

Flags

The OF, SF, ZF, AF, CF, and PF flags are set according to the result.

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