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Date: Wed, 11 Sep 2019 07:46:55 -0400
From: Rich Felker <dalias@...c.org>
To: musl@...ts.openwall.com
Subject: Re: [PATCH] mips: add single-instruction math functions

On Wed, Sep 11, 2019 at 01:05:04PM +0300, info@...ile-stream.com wrote:
> 
> non-commit text:
> gcc puts annoying nop into the delay slot for these functions, e.g.:
> 	abs.d	$f0,$f12
> 	jr	$ra
> 	 nop
> is there any way to get rid of this without using pure .S?

I think you don't want to get rid of it anyway, since if FPU emulation
is in use, emulation of floating point instructions in branch delay
slots is really problematic and requires nasty hacks with executable
stacks and whatnot. It would be nice if we could tell GCC not to put
the fpu instructions it generates in branch delay slots either, but I
don't know a way to do that.

Rich

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