From mboxrd@z Thu Jan 1 00:00:00 1970 In-Reply-To: <37D8DE44.9AE2C717@ssl.co.uk> Date: Fri, 10 Sep 1999 13:59:35 +0200 To: Sacha Varma , linuxppc-dev@lists.linuxppc.org From: Benjamin Herrenschmidt Subject: Re: altivec Message-Id: <19990910135935.015493@mailhost.mipsys.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Fri, Sep 10, 1999, Sacha Varma wrote: >There was some talk of trapping an illegal instruction interrupt in >Altivec-compiled code on non-Altivec processors and then emulating it in >software, but as I recall this was thought to be maybe impossible (due to >limited information about the illegal instruction and limits on what you can >do >in the trap) or more effort than it's worth. This is possible since Apple provides an emulator for developers (it's an extension that you drop in your MacOS system folder and which traps the illegal instruction interrupt). >In the meantime to learn more about Altivec I've been working on a library to >emulate the instructions in software (with appropriate #defines for the >language >extensions in a header). If anyone's interested e-mail me and I'll let you >know >if/when I'm done; I'm hoping to get the bulk of it done this weekend. (It'll >be >C++ I'm afraid - the vector types lend themselves nicely to a template class, >and a lot of the vec_* instructions are overloaded). If your library can be turned into plain C, then we should be able to implement the same emulation mecanism in Linux, but is it really interesting ? It will be way too slow to be useful for anything but developers prototyping Altivec code on G3s. -- Perso. e-mail: Work e-mail: BenH. Web : ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/