The AVX + JIT bug is hitting more frequently now. On a AVX machine the loop vectorizer goes for a vector length of 8 for some of my functions which in turn causes a SEGFAULT. Is there a way to limit the loop vectorizer to a certain vector length, say 4, such that I can work around the bug? Frank
I am asking because the option 'force-vector-width' is too restrictive. I would like to leave open the possibility to use vector width 2. Frank On 12/11/13 10:05, Frank Winter wrote:> The AVX + JIT bug is hitting more frequently now. On a AVX machine the > loop vectorizer goes for a vector length of 8 for some of my functions > which in turn causes a SEGFAULT. > > Is there a way to limit the loop vectorizer to a certain vector length, > say 4, such that I can work around the bug? > > Frank > >
On 12 November 2013 15:14, Frank Winter <fwinter at jlab.org> wrote:> I am asking because the option 'force-vector-width' is too restrictive. > I would like to leave open the possibility to use vector width 2.I was about to say that, and you saved us both one cycle. ;) What you could do is to force an architecture that doesn't have AVX, only SSE. I'm not sure how to do that on the JIT, I suppose setting the Target attributes would be enough. Nor I know what CPU string limits support to SSE, but that should do it. cheers, --renato -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20131112/59b586c6/attachment.html>