. 3 . , 3. " " " " , >-128 < 127 . (-128..127) , 80386, PENTIUM.
3. .
| E | ||
| N | ||
| G | ||
| L | ||
| A | , | |
| B | , |
, , . :
- , ( );
- CMP.
CMP:
CMP , CMP 1, 2.
(1 - 2) (- ), , 4.
4. ,
| OF | SF | ZF | CF | |
| < | H | H | ||
| = | H | H | ||
| > | H | H | ||
| < | 0/1 | H | ||
| = | H | |||
| > | 0/1 | H |
:
-"H" , ' " , ;
- 0/1 , 1 0 ( ).
5, . '/' , , . , _1 >_2, , _1 ( ) _2.
5. .
| JE | _1 = _2 | ZF=1 | |
| JNE | _1 <> _2 | ZF=0 | |
| JL/JNGE | _1 < _2 | SF<>OF | |
| JLE/JNG | _1 <= _2 | SF<>OF ZF=1 | |
| JG/JNLE | _1 > _2 | SF=OF ZF=0 | |
| JG/JNL | _1 >= _2 | SF=OF | |
| JGE/JNAE | _1 < _2 | CF=1 | |
| JBE/JNA | _1 <= _2 | CF=1 ZF=1 | |
| JA/JNBE | _1 > _2 | CF=0 ZF=0 | |
| JAE/JNB | _1 => _2 | CF=0 |
|
|
|
1.3
JMP. : JMP [] _.
, , .
. . _. . , - .
, IP. : , , .
,
JMP 127 . 2 : - , . , . - , , . , JMP, . , JMP, , . JMP SHORT PTR ( - SHORT POINTER ).
, 3 , . , 64 JMP .
, JMP , , .
NEAR, .. , .
, .
|
|
|
. , , .
1.4
INC () DEC (), , , . :
INC ,
DEC .
, , , . , , , , : LOOP .
' '. :
- 1 ;
- ;
- =0, LOOP , .
: LOOPE/LOOPZ , " , <>0 ZF=0". , . :
- >0 ZF=1, , =0 ZF=0, LOOPE/LOOPZ .
LOOPNE/LOOPNZ , , " , <>0 ZF=1". . :
- >0 ZF=0, , =0 ZF=1, LOOPNE/LOOPNZ .
, , !
, . .
2
1. ASCII : 5, 6, 7, 8, 9;
2. ( 20 ) ;
3. , ;
4. ;
5. ;
6. .
