search for: neons

On 25 March 2016 at 04:11, Hal Finkel <hfinkel at anl.gov> wrote: > As I understand it, the fundamental property being addresses here is: Are the semantics of scalar FP math the same as vector FP math? TTI seems like a good place to expose that information. If the semantics are indeed different, then the vectorizer would require fast-math flags in order to vectorize FP operations

On Fri, Mar 25, 2016 at 01:23:03PM +0000, Renato Golin via llvm-dev wrote: > On 25 March 2016 at 04:11, Hal Finkel <hfinkel at anl.gov> wrote: > > As I understand it, the fundamental property being addresses here is: Are > > the semantics of scalar FP math the same as vector FP math? TTI seems like > > a good place to expose that information. If the semantics are indeed

On Nov 25, 2014, at 10:07 AM, Viswanath Puttagunta <viswanath.puttagunta at linaro.org> wrote: > > > Also is there plans to make the NEON optimisations on ARMv7 run time > > detectable like they have in cairo/pixman? For generic distributions > > it would nice to be able to be able to enable them as they offer > > decent performance improvements but have the code

Hi Renato, As I understand it, the fundamental property being addresses here is: Are the semantics of scalar FP math the same as vector FP math? TTI seems like a good place to expose that information. If the semantics are indeed different, then the vectorizer would require fast-math flags in order to vectorize FP operations (similarly, gcc's man page says it requires

Thanks, that helps a lot. > All chips (to date) with NEON have VFP3, so it's safe to assume that a -mfpu=neon will have VFP3, so all the decisions > about code generated for VFP3 can safely be assumed by targets with NEON. Just to confirm my understanding, can I correctly say in general that the llc code generator might blur distinctions between NEON and VFP3 when it can do so

On 22 March 2016 at 11:34, James Molloy <James.Molloy at arm.com> wrote: > I don’t think this part is right. The denormal flag would have to be set by > whatever code generates the FP instruction, which would be Clang’s codegen > layer. So the if (Darwin) would be there, not in TTI. Right, I meant the information to set/not set would be in TTI, not the actual setting. I don't

On 7 June 2013 07:05, Owen Anderson <resistor at mac.com> wrote: > Darwin uses NEON for floating point, but does *not* (and should not). > globally enable fast math flags. Use of NEON for FP needs to remain > achievable without globally setting the fast math flags. Fast math may > imply reasonably imply NEON, but the opposite direction is not accurate. > > That said, I

>> Darwin uses NEON for floating point, but does *not* (and should not). >> globally enable fast math flags. Use of NEON for FP needs to remain >> achievable without globally setting the fast math flags. Fast math may >> imply reasonably imply NEON, but the opposite direction is not accurate. | Good point. Fast math is probably a too tough requirement. I need to | look

I tried to speed up Dhrystone on ARM Cortex-A8 by optimizing the memcpy intrinsic. I used the Neon load multiple instruction to move up to 48 bytes at a time . Over 15 scalar instructions collapsed down into these 2 Neon instructions. fldmiad r3, {d0, d1, d2, d3, d4, d5} @ SrcLine dhrystone.c 359 fstmiad r1, {d0, d1, d2, d3, d4, d5} It seems like this should be faster. But I did

On 06/06/2013 11:58 PM, Renato Golin wrote: > On 7 June 2013 07:05, Owen Anderson <resistor at mac.com> wrote: Hi Owen, hi Renato, thanks for your replies. >> Darwin uses NEON for floating point, but does *not* (and should not). >> globally enable fast math flags. Use of NEON for FP needs to remain >> achievable without globally setting the fast math flags. Fast

On May 27, 2011, at 10:49 AM, David Dunkle wrote: > Thanks, that helps a lot. > >> All chips (to date) with NEON have VFP3, so it's safe to assume that a > -mfpu=neon will have VFP3, so all the decisions >> about code generated for VFP3 can safely be assumed by targets with > NEON. > > Just to confirm my understanding, can I correctly say in general that >

On 27 May 2011 02:04, David Dunkle <ddunkle at arxan.com> wrote: > In all cases, I get code that looks pretty very the same; its like what > is below. However, I am expecting to see instruction level differences > between the vfp3 and neon versions. When I do the same with gcc 4.2 I do > see differences in the generated code. Hi David, You could see different instructions (as

On Nov 9, 2009, at 5:59 PM, David Conrad wrote: > On Nov 9, 2009, at 7:34 PM, Neel Nagar wrote: > >> I tried to speed up Dhrystone on ARM Cortex-A8 by optimizing the >> memcpy intrinsic. I used the Neon load multiple instruction to move >> up >> to 48 bytes at a time . Over 15 scalar instructions collapsed down >> into these 2 Neon instructions. Nice. Thanks

> |I just looked again at the +neonfp flag. Compiling with and without > |+neonfp flag seems to only affect scalar types in the attached test > |case. If e.g. the LLVM vectorizer introduces vector instructions on > |LLVM-IR level floating point vectors still yield NEON assembly even if > |compiled with "-mattr=+neon,-neonfp". Is this expected? > > I'm virtually

I have a code generation question for ARM with VFP and NEON. I am generating code for the following function as a test: void FloatingPointTest(float f1, float f2, float f3) { float f4 = f1 * f2; if (f4 > f3) printf("%f\n",f2); else printf("%f\n",f3); } I have tried compiling with: 1. -mfloat-abi=softfp and -mfpu=neon 2.

On 25 November 2014 at 10:11, Viswanath Puttagunta <viswanath.puttagunta at linaro.org> wrote: > > On 25 November 2014 at 09:39, Jonathan Lennox <jonathan at vidyo.com> wrote: > > > > On Nov 25, 2014, at 10:07 AM, Viswanath Puttagunta <viswanath.puttagunta at linaro.org> wrote: > >> > >> > Also is there plans to make the NEON optimisations

Hi, I was recently looking into the translation of LLVM-IR vector instructions to ARM NEON assembly. Specifically, when this is legal to do and when we need to be careful. I attached a very simple test case: define <4 x float> @fooP(<4 x float> %A, <4 x float> %B) { %C = fmul <4 x float> %A, %B ret <4 x float> %C } If fooP is compiled with "llc -march=arm

Hello LLVM Devs, I am starting my PhD on Automatic Parallelization for DSP and want to play with some ARM NEON intrinsics for a start. I spent the last three days trying to compile a version of LLVM that would allow me to compile sources that contain these intrinsics, but with no success. In the process I found out that clang doesn't support NEON (as per

On Nov 11, 2009, at 3:27 AM, Rodolph Perfetta wrote: > > If you know about the alignment, maybe use structured load/store > (vst1.64/vld1.64 {dn-dm}). You may also want to work on whole cache > lines > (64 bytes on A8). You can find more in this discussion: > http://groups.google.com/group/beagleboard/browse_thread/thread/12c7bd415fbc >

Hi, We are now about halfway between the 3.4 and 3.5 releases, and I would like to start preparing for a 3.4.1 release. Here is my proposed release schedule: Mar 26 - April 9: Identify and backport additional bug fixes to the 3.4 branch. April 9 - April 18: Testing Phase April 18: 3.4.1 Release How you can help: - If you have any bug fixes you think should be included to 3.4.1, send me an