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RE: [PATCH, ARM] PR41780
> Sebastian Huber wrote:[mailto:sebastian.huber@embedded-brains.de]
> Thanks for the review. Please have a look at the new patch.
>
> 2009-12-09 Sebastian Huber <sebastian.huber@embedded-brains.de>
>
> * config/arm/lib1funcs.asm (__prefer_thumb__): New define.
> (udivsi3, aeabi_uidivmod, divsi3, aeabi_idivmod): Use Thumb-1
> variant
> if defined __prefer_thumb__.
>
OK.
R.
> Richard Earnshaw wrote:
> >
> >> the changes for revision 150545 in config/arm/lib1funcs.asm
> introduced a
> >> problem for THUMB version 1 with an architecture other than
> >> __ARM_ARCH_6M__.
> >> See also http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41780.
> >>
> >> r150545 | kazu | 2009-08-06 23:05:42 +0200 (Thu, 06 Aug 2009) | 4
> lines
> >>
> >> * config/arm/lib1funcs.asm (ARM_DIV_BODY): Add Thumb-2
> >> implementation.
> >> (udivsi3, aeabi_uidivmod, divsi3, aeabi_idivmod): Only use
> >> Thumb-1
> >> implementation on ARMv6-M.
> >>
> >> The define __ARM_ARCH_6M__ is not necessary for THUMB version 1.
> THUMB
> >> version
> >> 1 will be used if and only if defined(__thumb__) &&
> >> !defined(__thumb2__).
> >>
> >> 2009-12-09 Sebastian Huber <sebastian.huber@embedded-brains.de>
> >>
> >> * config/arm/lib1funcs.asm (__thumb1__): New define.
> >> (udivsi3, aeabi_uidivmod, divsi3, aeabi_idivmod): Use Thumb-1
> >> variant
> >> if defined __thumb1__.
> >
> > Hmm, don't like this much. Part of the reason for the change was that
> the
> > thumb-1 code is much slower than the ARM equivalent and the problem
> you are
> > reporting only exists when interworking is disabled -- so you are
> killing
> > performance for people who aren't affected by your problem.
> >
> > Nevertheless, the Thumb code is smaller than the ARM equivalent, so
> there is
> > a case for sometimes using that even when interworking is enabled.
> >
> > Please can you adjust your patch to only apply when there is no
> interworking
> > support or when optimizing for space. You'll probably then want to
> rename
> > your macro to __prefer_thumb__.
> >
> > R.
> >
> >
>
>
> --
> Sebastian Huber, embedded brains GmbH
>
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>
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