nathan.zook@amd.com wrote:
> > if((a == b) | (c == d) | (e < f))
>
> I'm right when I say "The rules have changed. Consider bit-logicals. Time
> your critical inner loops". It all depends on the exact details of the code
> & the processor. When c, d, e, and f are simple variables and the first two
> branches are hard to predict, bit-ors should be faster on all the latest
> superscalar systems.
If c, d, e and f are simple variables, then the compiler should be able to
tell that it makes no difference whatsoever whether | or || is used, and
should generate the same (fastest) code for both.
Unfortunately, it doesn't look like gcc (as of egcs 2.91.66) is up to the
task...
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This archive was generated by hypermail 2b29 : Tue Feb 29 2000 - 21:00:14 EST