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Re: EGCS vs GCC performance


On Wed, Jan 14, 1998 at 11:39:40AM -0700, Jeffrey A Law wrote:
> Right.  Actually for the x86 the first thing we're being nailed by
> is the alignment of doubles (at least that's my understanding).

well, most people still compile integer code.. the problem with double
alignment is that the difference in speed can get very very large, so it's
immediately noticable when sth. gets wrong (and egcs will be blamed ;(

> And scheduling problems.  The x86 port really needs some work before it'll
> be generally profitable to enable instruction scheduling.

pgcc has enabled instruction scheduling for a long time... the
i386.md file seems not to be too different, and generally the
speed improvement with the old scheduler is 3-5%, even more
with -frisc (== a crude way of splitting instructions)

i'm currently hacking on the haifa scheduler parameters, but
without a pppro available, this will only help pentiums
(if at all).

      -----==-                                              |
      ----==-- _                                            |
      ---==---(_)__  __ ____  __       Marc Lehmann       +--
      --==---/ / _ \/ // /\ \/ /       pcg@goof.com       |e|
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    The choice of a GNU generation                        |
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