Re: ridiculous amounts of padding

[John Wehle <john at feith dot com>]

> I'm also pretty new to the i386, I'm more used to m68k. I've given a few 
> code fragments to fellow OpenBSD developpers, and what's come out is that
> egcs produces larger code, apparently because it prefers leaving stuff
> in memory to using registers when code speed is the same... but size
> is definitely not the same.

You mentioned a similar problem involving regmove in December.

  1) Did the patch I mentioned help?

  2) Does the problem occur using current snapshots?

Code fragments where current egcs snapshots don't compile to efficient
instruction sequences (or when using -Os the instruction sequence is
overly large) are of interest, especially if older versions of the
compiler (or gcc 2.8) do a better job when using the same compiler
options.  Keep in mind that there are cases where egcs will produce
larger code in the interest of performance, and that it's not always
obvious from code inspection why it's being done.  -Os addresses some
of the speed versus size issues, though I'm sure it can be improved
(especially if someone can point out the exact failing :-).

> I am not trying to start a flamewar here, just trying to get some help.

There are certainly people here willing to help though at times it may
take a while for someone to get back to you due to other things being in
their queue.  Anything you can do to supply specifics (or small test cases)
which isolate the problem helps tremendously.

-- John
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