Go4Expert - a urgent reply needed

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- - a urgent reply needed (http://www.go4expert.com/showthread.php?t=20544)

a urgent reply needed

say the output for the following code with explanation how is it implemented inside the compiler : main() { int i=3,j; j=i++ + i++; printf("%d %d",i,j); } thanks in advance

Re: a urgent reply needed

My compiler (VS2008, debug,x86) implements it thus:

Code:

main() { int i=3,j; j=i++ + i++; printf("%d %d",i,j); }

00063950  push        ebp  

00063951  mov         ebp,esp 

00063953  sub         esp,0D8h 

00063959  push        ebx  

0006395A  push        esi  

0006395B  push        edi  

0006395C  lea         edi,[ebp-0D8h] 

00063962  mov         ecx,36h 

00063967  mov         eax,0CCCCCCCCh 

0006396C  rep stos    dword ptr es:[edi] 

0006396E  mov         dword ptr [i],3 

00063975  mov         eax,dword ptr [i] 

00063978  add         eax,dword ptr [i] 

0006397B  mov         dword ptr [j],eax 

0006397E  mov         ecx,dword ptr [i] 

00063981  add         ecx,1 

00063984  mov         dword ptr [i],ecx 

00063987  mov         edx,dword ptr [i] 

0006398A  add         edx,1 

0006398D  mov         dword ptr [i],edx 

00063990  mov         esi,esp 

00063992  mov         eax,dword ptr [j] 

00063995  push        eax  

00063996  mov         ecx,dword ptr [i] 

00063999  push        ecx  

0006399A  push        offset string "%d %d" (6573Ch) 

0006399F  call        dword ptr [__imp__printf (68374h)] 

000639A5  add         esp,0Ch 

000639A8  cmp         esi,esp 

000639AA  call        @ILT+335(__RTC_CheckEsp) (61154h) 

000639AF  xor         eax,eax 

000639B1  pop         edi  

000639B2  pop         esi  

000639B3  pop         ebx  

000639B4  add         esp,0D8h 

000639BA  cmp         ebp,esp 

000639BC  call        @ILT+335(__RTC_CheckEsp) (61154h) 

000639C1  mov         esp,ebp 

000639C3  pop         ebp  

000639C4  ret

Re: a urgent reply needed

first thank u for ur effort........ Actually i dunno 8086 assembly programming , now only learning ... so only am not able to appreciate ur program.... can u pl. tell me the implementation more easily from the compiler point of view ??????:undecided:undecided

Re: a urgent reply needed

What is it you want to know? You've been told in another thread that expressions of this sort:

Code:

j=i++ + i++;

are undefined and compiler dependent. In the case of this code, it appears that j is assigned i+i (3+3=6) then i is incremented twice (i++; i++; so i is now 5), but not until after the assignment operation.

There's no reason why any sane programmer would ever need to use such an expression.

Why is this "urgent"?

Re: a urgent reply needed

no no , actually i had a debugging test day before yest... that's why i put urgent.... and u are correct , it's purely compiler dependent ... i too saw today.......:pleased::pleased: in other compiler it's printing as 7........

thank u