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Use backtick code blocks for syntax highlighting

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James Gregory 2013-12-31 11:38:48 +11:00
commit f658bfbb40
203 changed files with 26546 additions and 25801 deletions
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44
04-05.md
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@ -43,29 +43,33 @@ Listing 4.6.*](images/04-04.jpg)
**LISTING 4.7 LST4-7.ASM**
; Measures the performance of repeated MOV AL,0 instructions,
; which take 4 cycles each according to Intel's official
; specifications.
;
sub ax,ax
call ZTimerOn
rept 1000
mov al,0
endm
call ZTimerOff
```nasm
; Measures the performance of repeated MOV AL,0 instructions,
; which take 4 cycles each according to Intel's official
; specifications.
;
sub ax,ax
call ZTimerOn
rept 1000
mov al,0
endm
call ZTimerOff
```
**LISTING 4.8 LST4-8.ASM**
; Measures the performance of repeated SUB AL,AL instructions,
; which take 3 cycles each according to Intel's official
; specifications.
;
sub ax,ax
call ZTimerOn
rept 1000
sub al,al
endm
call ZTimerOff
```nasm
; Measures the performance of repeated SUB AL,AL instructions,
; which take 3 cycles each according to Intel's official
; specifications.
;
sub ax,ax
call ZTimerOn
rept 1000
sub al,al
endm
call ZTimerOff
```
As you can see, it's easy to be drawn into thinking you're saving cycles
when you're not. You can only improve the performance of a specific bit