Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 21 Mar 2003 08:42:41 +1000
From:      Peter Grehan <grehan@freebsd.org>
To:        Andrew Gallatin <gallatin@cs.duke.edu>
Cc:        Jake Burkholder <jake@locore.ca>, src-committers@freebsd.org, cvs-src@freebsd.org, cvs-all@freebsd.org
Subject:   Re: cvs commit: src/sys/powerpc/powerpc fpu.c genassym.c swtch.S trap.c
Message-ID:  <3E7A43E1.DA0D75F0@freebsd.org>
References:  <200303201028.h2KASKU9090258@repoman.freebsd.org> <20030320110240.A3985@grasshopper.cs.duke.edu> <20030320144838.O76446@locore.ca> <15994.7655.668902.294563@grasshopper.cs.duke.edu>

next in thread | previous in thread | raw e-mail | index | archive | help
> Yes.  At least on the alpha, gcc uses the floating point
> registers/instructions extensively.  So even a process which isn't
> intentionally using floating point will likely take a FEN trap.

 Although I've not seen it, this does appear to be the case with PPC as well,
judging by a recent NetBSD thread:

  http://mail-index.netbsd.org/port-powerpc/2003/03/17/0001.html

> From what I can see, NetBSD still seems to be using lazy FP though.

 They do the full-blown lazy save/restore and MP IPI stuff on PPC. It might
be worth it for Altivec, since it's an additional 32 x 128 bits of context
to save.

later,

Peter.

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe cvs-all" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3E7A43E1.DA0D75F0>