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* Re: about the 'for' statement
@ 1999-08-16 10:54 R. Kelley Cook
  1999-08-16 11:33 ` Per Bothner
  1999-08-31 23:20 ` R. Kelley Cook
  0 siblings, 2 replies; 8+ messages in thread
From: R. Kelley Cook @ 1999-08-16 10:54 UTC (permalink / raw)
  To: egcs

On 16 Aug 1999 09:03:09 +0200, Wang Yong wrote:

>Hi, all
>  in gcc, how 'for' statement is translated? 
>
>  for example:
>
>  for (i=1;i++;i<10){
>      //some statement here
>  }
>

Strange question, you already wrote enough to check the answer yourself.

All you had to do was change your code to be ...  

 for (i=1;i++;i<10){
   printf("%d",i);  //some statement here
 }

and you would have realized the answer.


>  If this for statement will be translated to something like this :
>
>  i=1;
>l1:
>  if (i<10){
>        //some statements here
>        i++;
>        goto l1;
>  }
>

yes

>or
>
>  i=1;
>l1:
>  i++;
>  if (i<10){
>        //some statements here
>        goto l1;
>  }

no



^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: about the 'for' statement
  1999-08-16 10:54 about the 'for' statement R. Kelley Cook
@ 1999-08-16 11:33 ` Per Bothner
  1999-08-31 23:20   ` Per Bothner
  1999-08-31 23:20 ` R. Kelley Cook
  1 sibling, 1 reply; 8+ messages in thread
From: Per Bothner @ 1999-08-16 11:33 UTC (permalink / raw)
  To: R. Kelley Cook; +Cc: egcs

"R. Kelley Cook" <KCook@IBM.net> writes:

> >  for (i=1;i++;i<10){
> >      //some statement here
> >  }

> >  If this for statement will be translated to something like this :
> >
> >  i=1;
> >l1:
> >  if (i<10){
> >        //some statements here
> >        i++;
> >        goto l1;
> >  }
> >
> 
> yes

Wrong.  Try:

  i=1;
  l1:
  if (i++){
     //some statements here
     i<10;  // no-op.
     goto l1;
  }

I.e. the i++ and i<10 are probably switched ...
-- 
	--Per Bothner
bothner@pacbell.net  per@bothner.com   http://home.pacbell.net/bothner/

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: about the 'for' statement
  1999-08-16 11:33 ` Per Bothner
@ 1999-08-31 23:20   ` Per Bothner
  0 siblings, 0 replies; 8+ messages in thread
From: Per Bothner @ 1999-08-31 23:20 UTC (permalink / raw)
  To: R. Kelley Cook; +Cc: egcs

"R. Kelley Cook" <KCook@IBM.net> writes:

> >  for (i=1;i++;i<10){
> >      //some statement here
> >  }

> >  If this for statement will be translated to something like this :
> >
> >  i=1;
> >l1:
> >  if (i<10){
> >        //some statements here
> >        i++;
> >        goto l1;
> >  }
> >
> 
> yes

Wrong.  Try:

  i=1;
  l1:
  if (i++){
     //some statements here
     i<10;  // no-op.
     goto l1;
  }

I.e. the i++ and i<10 are probably switched ...
-- 
	--Per Bothner
bothner@pacbell.net  per@bothner.com   http://home.pacbell.net/bothner/

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: about the 'for' statement
  1999-08-16 10:54 about the 'for' statement R. Kelley Cook
  1999-08-16 11:33 ` Per Bothner
@ 1999-08-31 23:20 ` R. Kelley Cook
  1 sibling, 0 replies; 8+ messages in thread
From: R. Kelley Cook @ 1999-08-31 23:20 UTC (permalink / raw)
  To: egcs

On 16 Aug 1999 09:03:09 +0200, Wang Yong wrote:

>Hi, all
>  in gcc, how 'for' statement is translated? 
>
>  for example:
>
>  for (i=1;i++;i<10){
>      //some statement here
>  }
>

Strange question, you already wrote enough to check the answer yourself.

All you had to do was change your code to be ...  

 for (i=1;i++;i<10){
   printf("%d",i);  //some statement here
 }

and you would have realized the answer.


>  If this for statement will be translated to something like this :
>
>  i=1;
>l1:
>  if (i<10){
>        //some statements here
>        i++;
>        goto l1;
>  }
>

yes

>or
>
>  i=1;
>l1:
>  i++;
>  if (i<10){
>        //some statements here
>        goto l1;
>  }

no



^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: about the 'for' statement
  1999-08-16  2:19 ` Branko Cibej
@ 1999-08-31 23:20   ` Branko Cibej
  0 siblings, 0 replies; 8+ messages in thread
From: Branko Cibej @ 1999-08-31 23:20 UTC (permalink / raw)
  To: Wang Yong; +Cc: gcc maillist

Wang Yong wrote:

> Hi, all
>   in gcc,

This has nothing to do with gcc. This is a question about the
C (or C++) language.

> how 'for' statement is translated?
>
>   for example:
>
>   for (i=1;i++;i<10){
>       //some statement here
>   }
>
>   If this for statement will be translated to something like this :
>
>   i=1;
> l1:
>   if (i<10){
>         //some statements here
>         i++;
>         goto l1;
>   }
>
> or
>
>   i=1;
> l1:
>   i++;
>   if (i<10){
>         //some statements here
>         goto l1;
>   }

Neither, of course :-)  From your example, you'll get this:

       i=1;
     l1:
       if (i++)
         {
           /*some statements here*/
           i<10;
           goto l1;
         }

On the other hand, if you put the condition in the right place:

     for (i=1; i<10; i++)
       {
         /*some statements here*/
       }

you'll get your first expansion.

    Brane

--
Branko &Ccaron;ibej                 <branko.cibej@hermes.si>
HERMES SoftLab, Litijska 51, 1000 Ljubljana, Slovenia
voice: (+386 61) 186 53 49   fax: (+386 61) 186 52 70


^ permalink raw reply	[flat|nested] 8+ messages in thread
* about the 'for' statement
  1999-08-16  0:02 Wang Yong
  1999-08-16  2:19 ` Branko Cibej
@ 1999-08-31 23:20 ` Wang Yong
  1 sibling, 0 replies; 8+ messages in thread
From: Wang Yong @ 1999-08-31 23:20 UTC (permalink / raw)
  To: gcc maillist

Hi, all
  in gcc, how 'for' statement is translated? 

  for example:

  for (i=1;i++;i<10){
      //some statement here
  }

  If this for statement will be translated to something like this :

  i=1;
l1:
  if (i<10){
        //some statements here
        i++;
        goto l1;
  }

or

  i=1;
l1:
  i++;
  if (i<10){
        //some statements here
        goto l1;
  }



^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: about the 'for' statement
  1999-08-16  0:02 Wang Yong
@ 1999-08-16  2:19 ` Branko Cibej
  1999-08-31 23:20   ` Branko Cibej
  1999-08-31 23:20 ` Wang Yong
  1 sibling, 1 reply; 8+ messages in thread
From: Branko Cibej @ 1999-08-16  2:19 UTC (permalink / raw)
  To: Wang Yong; +Cc: gcc maillist

Wang Yong wrote:

> Hi, all
>   in gcc,

This has nothing to do with gcc. This is a question about the
C (or C++) language.

> how 'for' statement is translated?
>
>   for example:
>
>   for (i=1;i++;i<10){
>       //some statement here
>   }
>
>   If this for statement will be translated to something like this :
>
>   i=1;
> l1:
>   if (i<10){
>         //some statements here
>         i++;
>         goto l1;
>   }
>
> or
>
>   i=1;
> l1:
>   i++;
>   if (i<10){
>         //some statements here
>         goto l1;
>   }

Neither, of course :-)  From your example, you'll get this:

       i=1;
     l1:
       if (i++)
         {
           /*some statements here*/
           i<10;
           goto l1;
         }

On the other hand, if you put the condition in the right place:

     for (i=1; i<10; i++)
       {
         /*some statements here*/
       }

you'll get your first expansion.

    Brane

--
Branko &Ccaron;ibej                 <branko.cibej@hermes.si>
HERMES SoftLab, Litijska 51, 1000 Ljubljana, Slovenia
voice: (+386 61) 186 53 49   fax: (+386 61) 186 52 70


^ permalink raw reply	[flat|nested] 8+ messages in thread
* about the 'for' statement
@ 1999-08-16  0:02 Wang Yong
  1999-08-16  2:19 ` Branko Cibej
  1999-08-31 23:20 ` Wang Yong
  0 siblings, 2 replies; 8+ messages in thread
From: Wang Yong @ 1999-08-16  0:02 UTC (permalink / raw)
  To: gcc maillist

Hi, all
  in gcc, how 'for' statement is translated? 

  for example:

  for (i=1;i++;i<10){
      //some statement here
  }

  If this for statement will be translated to something like this :

  i=1;
l1:
  if (i<10){
        //some statements here
        i++;
        goto l1;
  }

or

  i=1;
l1:
  i++;
  if (i<10){
        //some statements here
        goto l1;
  }



^ permalink raw reply	[flat|nested] 8+ messages in thread
end of thread, other threads:[~1999-08-31 23:20 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
1999-08-16 10:54 about the 'for' statement R. Kelley Cook
1999-08-16 11:33 ` Per Bothner
1999-08-31 23:20   ` Per Bothner
1999-08-31 23:20 ` R. Kelley Cook
  -- strict thread matches above, loose matches on Subject: below --
1999-08-16  0:02 Wang Yong
1999-08-16  2:19 ` Branko Cibej
1999-08-31 23:20   ` Branko Cibej
1999-08-31 23:20 ` Wang Yong

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