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Date: Thu, 16 Apr 2020 18:02:35 -0500
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Florian Weimer <fw@deneb.enyo.de>
Subject: Re: [musl] Powerpc Linux 'scv' system call ABI proposal take 2
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On Thu, Apr 16, 2020 at 08:12:19PM +0200, Florian Weimer wrote:
> > I think my choice would be just making the inline syscall be a single
> > call insn to an asm source file that out-of-lines the loading of TOC
> > pointer and call through it or branch based on hwcap so that it's not
> > repeated all over the place.
> 
> I don't know how problematic control flow out of an inline asm is on
> POWER.  But this is basically the -moutline-atomics approach.

Control flow out of inline asm (other than with "asm goto") is not
allowed at all, just like on any other target (and will not work in
practice, either -- just like on any other target).  But the suggestion
was to use actual assembler code, not inline asm?


Segher