Re: Stable cvs version for 2.4

Steve Wahl
2002-09-04T15:19:35Z

On Wed, Sep 04, 2002 at 03:54:03PM +0100, Jasmine Strong wrote:
>
>
> On Wed, 4 Sep 2002, Allen Curtis wrote:
>
> > How about we add 1 byte which contains up to 8 bit fields?
>
> Adding a byte will destroy the alignment. you'd have to add a whole word.
>
> We could have a #define to set whether we use the lsb of the address (on
> aligned architectures) or an extra byte (on non-aligned architectures,
> which won't care about the structure not being an exact multiple of words
> anyway).

My $0.02 is:

The #define is a good suggestion.

But the assumption that using the lsb of the pointer will only break
on archetectures that don't care about alignment may be a bad one.

I haven't looked at the code (shame on me...), but I thought I heard
the word "tree" mentioned. :-) If this data structure is being used
for speed, I have to ask if the extra masking instructions are a good
trade off for the memory saved?