Just a little something that has been bothering me.
GORDON KEEGAN
c145gmk at utarlg.utarl.edu
Tue Dec 11 10:11:45 AEST 1990
In article <1990Dec08.222943.1581 at cs.widener.edu>, sven at cs.widener.edu (Sven Heinicke) writes...
>What is quicker?
>
> int a = 0,i = 0;
>
>or
>
> int a,i;
> i = a = 0;
>
>and why?
>
>This type of thing has been bothering me for a long time.
Our C compiler under VMS 5.3-1 produced the following
assembler code for the respective C segments:
int a=0, i=0;
F8 AD 00 D0 000B movl #0,-8(fp)
F4 AD 00 D0 000F movl #0,-12(fp)
and
int a, i;
i = a = 0;
F8 AD 00 D0 000B movl #0,-8(fp)
F4 AD F8 AD D0 000F movl -8(fp),-12(fp)
The second will be marginally slower, but only just...
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