similar to: [LLVMdev] Has something changed in LLVM BUG tracking system ?

Hi Renato, You're right it's VMLA/VMLS that are generated. Still don't understand what drives generation for Cortex-A9. I was using fmac for floating point MAC not for fused MAC. Than I realized that we spoke about fma instead of fmac. So back to the original problem why when using -mcpu=cortex-a9 VMLA/VMLS are not generated and when I use -mtriple=armv7-eabi they are ? Best

cat /proc/cpuinfo ? Are you sure it's generating VFMA and not VMLA? On Fri, Nov 9, 2012 at 9:35 AM, Sebastien DELDON-GNB < sebastien.deldon at st.com> wrote: > Hi Renato, > > It's definitively not A15. Can this be the case that NEON units for > cortex-A9 support it but isn't documented/recommended ? > And as mentioned before code is working ! > > Seb >

Hi Renato, It's definitively not A15. Can this be the case that NEON units for cortex-A9 support it but isn't documented/recommended ? And as mentioned before code is working ! Seb > -----Original Message----- > From: rengolin at gmail.com [mailto:rengolin at gmail.com] On Behalf Of > Renato Golin > Sent: Friday, November 09, 2012 6:27 PM > To: Sebastien DELDON-GNB >

Hi James, Thanks for the answer, for Cortex-A9 would you recommend to generate thumb2 code or ARM code ? What would be the best performance wise ? Best Regards Seb > -----Original Message----- > From: James Molloy [mailto:james.molloy at arm.com] > Sent: Thursday, May 31, 2012 9:57 AM > To: Sebastien DELDON-GNB > Cc: llvmdev at cs.uiuc.edu > Subject: Re: [LLVMdev] llc support

Hi Bastien, Weird gcc is generating fma for my platform STEricsson Novathor with Linaro, code works. It also works when I use LLVM to generate fma (using llc -mtriple=armv7-eabi). Maybe someone from ARM can answer the question ? Seb From: JF Bastien [mailto:jfb at google.com] Sent: Friday, November 09, 2012 5:36 PM To: Sebastien DELDON-GNB Cc: Anitha Boyapati; llvmdev at cs.uiuc.edu Subject:

Hi Sebastien, ARMv7-M has VFMA and LLVM's "triple" is far from perfect. Wikipedia tells me NovaThor can also be A15, or STE could have cramped a VFPv4 in it? ;) Or possibly, your code never branches into the VFMA. Many things could be happening, but usually, VFMA shouldn't be generated for A9. A GCC bug, maybe? On 9 November 2012 16:51, Sebastien DELDON-GNB

Hi Seb, The ARM instruction set is a fixed-width 32-bit instruction set that has been around since the early days of ARM. Modern (armv4t onwards) cores mostly have another instruction set that can be used in tandem, the "thumb" instruction set. This is a variable width (16 or 32 bit) instruction set that provides a subset of the ARM instruction set and was intended to provide the

Hi James, Thanks for the answer, can you elaborate on difference between thumb, thumb2, ARM, thumbv7. I'm a bit lost right now. When specifying thumbv7 llc will generate thumb only code, not thumb2 ? Best Regards Seb > -----Original Message----- > From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] > On Behalf Of James Molloy > Sent: Tuesday, May 29,

Hi Anitha, Thanks for your answer but -mcpu=cortex-a9 -mattr=+vfp4 doesn' t enable fused mac generation for me. I would like just to understand why -mtriple=armv7-eabi enables it while -mcpu=cortex-a9 seems to disable it ? Seb > -----Original Message----- > From: Anitha Boyapati [mailto:anitha.boyapati at gmail.com] > Sent: Thursday, November 08, 2012 10:22 AM > To: Sebastien

AFAIK A9 doesn't have VFPv4 or AdvSIMDv2, so it doesn't have VFMA. I don't know what LLVM does, but it shouldn't emit VFMA when you target A9. VMLA isn't a fused multiply-add, it's a multiply followed by an add and has different latency as well as precision. On Thu, Nov 8, 2012 at 4:57 AM, Sebastien DELDON-GNB < sebastien.deldon at st.com> wrote: > Hi Anitha,

Understood for the aligned case, I want to measure performance degradation for unaligned case. I mean unaligned case versus aligned. I know this is stupid, but I want to try to pass a <4 x float>* as parameter of a routine and at the call site I want to pass a misaligned pointer. Since LLVM is generating movapd instruction it will raise an exception (SEGFAULT), I just want to know if there

On Feb 28, 2011, at 2:58 AM, Sebastien DELDON-GNB wrote: > Understood for the aligned case, I want to measure performance degradation for unaligned case. > I mean unaligned case versus aligned. I know this is stupid, but I want to try to pass a <4 x float>* as parameter of a routine and at the call site I want to pass a misaligned pointer. Since LLVM is generating movapd instruction

Hi Renato, No I've used LNT before and it might not be as simple as you think to get it working here. I'll see what I can do, but It's unlikely I'll have much time to spend on this topic in the coming weeks. I'm more interested coming back to my original question, and would like to know how to proceed if I want to define my own LLVM intrinsic to generate VMLA instruction. My

Hi all, Is there a way to force llc to generate movupd instruction instead of movapd for x86 target ? I know that movapd is more performant, but I would like to measure degradation when alignment constraints are not met. Best Regards Seb -------------- next part -------------- An HTML attachment was scrubbed... URL:

Hi Lang & Renato, I eventually set up a panda board with latest linaro delivery (eabi-hf). I did some experiments using my own compiler and LLVM 3.2 as back-end. I use same flagset for my compiler (front-end) and just invoke llc with and without vmlx-forwarding attribute. So base arguments to llc are: llc -march=arm -mcpu=cortex-a9 -mattr=+neon -float-abi=hard to which I added

Hi Rotem, Thanks for the quick answer, how do I know which type is legal/illegal with respect to calling convention ? Best Regards Seb > -----Original Message----- > From: Rotem, Nadav [mailto:nadav.rotem at intel.com] > Sent: Thursday, July 05, 2012 11:21 AM > To: Sebastien DELDON-GNB; llvmdev at cs.uiuc.edu > Subject: RE: Vector argument passing abi for ARM ? > > The

Hi all, Does llc -march=thumb -mcpu=cortex-a9 enable generation of thumb2 code for armv7 ? Best Regards Seb -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20120727/da758ea0/attachment.html>

On 15 February 2013 16:00, Sebastien DELDON-GNB <sebastien.deldon at st.com>wrote: > to which I added –mattr=-vmlx-forwarding to disable vmlx forwarding for > cortex-a9. > > When I DISABLE vmlx forwarding I’m observing a 7% speed-up on ref dataset > for MILC. So I’m observing something similar to what I’ve observed on STE > platform available on SNOWBALL board. > Hi

On Sep 21, 2012, at 2:58 AM, Sebastien DELDON-GNB <sebastien.deldon at st.com> wrote: > Hi Eli, > > Thanks for the answer, it clarifies the situation for me. Do you know if there is Pass in LLVM that could be adapted to 'legalize' intrinsics calls ? > Or shall I define my own intrinsics for non supported types ? You should never generate these sorts of intrinsics with

Hi all, on following code: ; ModuleID = 'shufxbug.ll' target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32" target triple = "i386-pc-linux-gnu" define void @sample_test(<4 x float>* nocapture %source, <8 x float>* nocapture %dest) nounwind noinline { L.entry: