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Re: ARM patch: Keep track of condition codes in Thumb-1 mode


On 07/06/2010 11:28 AM, Bernd Schmidt wrote:
> A few weeks ago I changed the cbranchsi4_insn pattern so that it can
> take advantage of a compare insn output by a previous conditional
> branch.  This patch extends the mechanism to keep track of more kinds of
> cc-setting insns, in a way similar to that used on cc0 ports.

I wouldn't normally ping this after a few days, but...

> Discouraging the second alternative of
> the cbranchsi4_insn pattern tends to make reload work better:
> -       mov     r3, #0
> -       mov     r8, r0
>         mov     r5, r7
> -       cmp     r8, r3
> +       mov     r8, r0
> +       cmp     r0, #0

See my earlier post from today.  I've now found the real problem in
reload and will drop this part of the patch.


Bernd


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