search for: lcpxx

Displaying 2 results from an estimated 2 matches for "lcpxx".

2014 Sep 19
4
[LLVMdev] Please benchmark new x86 vector shuffle lowering, planning to make it the default very soon!
...'t observed any significant regression in our internal codebase. In one particular case I observed a slowdown (around 1%); here is what I found when investigating on this slowdown. 1. With the new shuffle lowering, there is one case where we end up producing the following sequence: vmovss .LCPxx(%rip), %xmm1 vxorps %xmm0, %xmm0, %xmm0 vblendps $1, %xmm1, %xmm0, %xmm0 Before, we used to generate a simpler: vmovss .LCPxx(%rip), %xmm1 In this particular case, the 'vblendps' is redundant since the vmovss would zero the upper bits in %xmm1. I am not sure why we get this poor-...
2014 Sep 10
13
[LLVMdev] Please benchmark new x86 vector shuffle lowering, planning to make it the default very soon!
On Tue, Sep 9, 2014 at 11:39 PM, Chandler Carruth <chandlerc at google.com> wrote: > Awesome, thanks for all the information! > > See below: > > On Tue, Sep 9, 2014 at 6:13 AM, Andrea Di Biagio <andrea.dibiagio at gmail.com> > wrote: >> >> You have already mentioned how the new shuffle lowering is missing >> some features; for example, you explicitly