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Re: New back end ia16: 16-bit Intel x86
On Fri, Aug 17, 2007 at 10:33:19PM -0700, H. Peter Anvin wrote:
> Rask Ingemann Lambertsen wrote:
> >
> > H. Peter Anvin wrote:
> >
> >> That backend just got to the point where we can compare code sizes; the
> >> code appears 10-20% smaller than the i386 backend with .code16gcc and
> >> -Os. Although that is less than I would have expected, that is without
> >> any optimizations whatsoever and so the resulting code is actually quite
> >> poor.
> >
> > You could probably save at least as much by using 16-bit integers, thus
> > avoiding the 0x66 prefixes.
>
> Yes, with 16-bit integers it reduced the code size even further.
I'm only now realizing that the back end Daniel Verkamp and you are
working on is strictly for i386+ code. Did you try tweaking things like
TARGET_HIMODE_MATH, TARGET_PARTIAL_REG_STALL and such in the existing i386
back end?
--
Rask Ingemann Lambertsen