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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
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04-04.md
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@ -104,32 +104,36 @@ that the "true" execution time of **SHR** is 8.64 cycles.
**LISTING 4.5 LST4-5.ASM**
; Measures the performance of 1,000 SHR instructions
; in a row. Since SHR executes in 2 cycles but is
; 2 bytes long, the prefetch queue is always empty,
; and prefetching time determines the overall
; performance of the code.
;
call ZTimerOn
rept 1000
shr ax,1
endm
call ZTimerOff
```nasm
; Measures the performance of 1,000 SHR instructions
; in a row. Since SHR executes in 2 cycles but is
; 2 bytes long, the prefetch queue is always empty,
; and prefetching time determines the overall
; performance of the code.
;
call ZTimerOn
rept 1000
shr ax,1
endm
call ZTimerOff
```
**LISTING 4.6 LST4-6.ASM**
; Measures the performance of 1,000 MUL/SHR instruction
; pairs in a row. The lengthy execution time of MUL
; should keep the prefetch queue from ever emptying.
;
mov cx,1000
sub ax,ax
call ZTimerOn
rept 1000
mul ax
shr ax,1
endm
call ZTimerOff
```nasm
; Measures the performance of 1,000 MUL/SHR instruction
; pairs in a row. The lengthy execution time of MUL
; should keep the prefetch queue from ever emptying.
;
mov cx,1000
sub ax,ax
call ZTimerOn
rept 1000
mul ax
shr ax,1
endm
call ZTimerOff
```
![**Figure 4.3**  *Execution and instruction prefetching sequence for
Listing 4.5.*](images/04-03.jpg)