General Integer Math

We learned negation with the NEG instruction in Chapter 4, "Bit Mangling," and binary multiplication (2 N ) and division using bit shifting in Chapter 5, "Bit Wrangling."

We can add 8-, 16-, 32-, and 64-bit numbers , and 4-bit if you include BCD (binary-coded decimal) discussed later in Chapter 15.

No 64-bit 

The general-purpose BCD instructions are not available in 64-bit mode!

The EFLAGS Overflow, Sign, Zero, Auxiliary Carry, Parity, and Carry are all altered when using the general-purpose instructions.

Overflow

Whether the numbers overflow the binary limit of the destination operand

Sign

Set to the resulting value of the MSB (most significant bit)

Zero

Set if the result is a value of zero

Aux. Carry

Set as a result of a carry of the low-order nibble

Parity

Set to 1 if the bits add up to an even number; 0 if not

Carry

Any mathematical carry results of the mathematical operation

ADD Add

ADC Add with Carry

ADD destination , source

Mnemonic

P

PII

K6

3D!

3Mx+

SSE

SSE2

A64

SSE3

E64T

ADC



32.64-Bit 80X86 Assembly Language Architecture
32/64-Bit 80x86 Assembly Language Architecture
ISBN: 1598220020
EAN: 2147483647
Year: 2003
Pages: 191

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