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Date: Wed, 30 Nov 2011 18:49:00 -0000
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Subject: Re: best ABI strategy ?
From: Aurelien Buhrig <aurelien.buhrig.gcc@gmail.com>
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> Hi,
>
> I'm trying to optimize our target ABI, and I'm wondering what is the
> best strategy to define it.
> Is there a paper, or any hint, dealing with this topic ?
> For instance,
> - which ratio between call-used-reg vs "static regs"
> - which ratio between arg regs vs call-used-reg
> - what should be return regs
> - ...
> I guess this problem is very target dependent, but there are maybe
> general ideas about this.
>
>
> In particular, for now my call-used regs set is the same that arg regs
> set. I noticed GCC would not use arg regs for reloading, (or would
> prefer others), even if they are not actually used by function args.
> and it generates extra push/pop of static regs. I there a way force
> gcc preferring using "free" arg regs ?
>
> Thank you by advance!
>
> Aur=E9lien

Forget the last point. GCC does use free arg regs. The testcases I
looked at were not relevant. Sorry!

Aur=E9lien