similar to: LLVM Vectorisation Bug

Hello, I am trying to vectorize following stencil code; #include <stdio.h> #define N 100351 // This function computes 2D-5 point Jacobi stencil void stencil(int a[restrict][N]) { int i, j, k; for (k = 0; k < 100; k++) { for (i = 1; i <= N-2; i++) { for (j = 1; j <= N-2; j++) { a[i][j] = 0.25 * (a[i][j] + a[i-1][j] + a[i+1][j] + a[i][j-1] +

I am able to vectorize it with the following code; #include <stdio.h> #define N 100351 // This function computes 2D-5 point Jacobi stencil void stencil(int a[][N], int b[][N]) { int i, j, k; for (k = 0; k < N; k++) { for (i = 1; i <= N-2; i++) for (j = 1; j <= N-2; j++) b[i][j] = 0.25 * (a[i][j] + a[i-1][j] + a[i+1][j] + a[i][j-1] + a[i][j+1]); for

Does it happen due to loop carried dependence? if yes what is the solution to vectorize such codes? please reply. i m waiting. On Jul 1, 2017 12:30 PM, "hameeza ahmed" <hahmed2305 at gmail.com> wrote: > I even tried polly but still my llvm IR does not contain vector > instructions. i used the following command; > > clang -S -emit-llvm stencil.c -march=knl -O3

Your problem is due to GVN partial reduction elimination (PRE) which introduces a PHI node the current loop vectorizer cannot handle: opt -O3 stencil.ll -pass-remarks=loop-vectorize -pass-remarks-missed=loop-vectorize -pass-remarks-analysis=loop-vectorize remark: <unknown>:0:0: loop not vectorized: value that could not be identified as reduction is used outside the loop remark:

<div> </div><div> </div><div>Hello,</div><div> </div><div>To me this is an issue in llvm loop vectorizer (if N is large enough to prevent complete unrolling of j-loop).</div><div> </div><div>Woud you mind to share stencil.ll than I would say more definitely what the issue

i want to implement gather for v64i32. i wrote following code. def GATHER_256B : I<0x68, MRMSrcMem, (outs VR_2048:$dst), (ins i2048mem:$src), "GATHER_256B\t{$src, $dst|$dst, $src}", [(set VR_2048:$dst, (v64i32 (masked_gather addr:$src)))], IIC_MOV_MEM>, TA; def: Pat<(v64f32 (masked_gather addr:$src)), (GATHER_256B

Hello, I did as you said, Please tell me whether the following correct now?? def GATHER_256B : I<0x68, MRMSrcMem, (outs VR_2048:$dst, _.KRCWM:$mask_wb), (VR_2048:$src1, _.KRCWM:$mask, ins i2048mem:$src2), "GATHER_256B\t{$src2, {$dst}{${mask}}|${dst} {${mask}}, $src2}"), [(set VR_2048:$dst, _.KRCWM:$mask_wb, (v64i32 (GatherNode

Thank You. Still getting errors.I have modified my instructions as you said as follows: def GATHER_256B : I<0x68, MRMSrcMem, (outs VR_2048:$dst, VK64WM:$mask_wb), (ins VR_2048:$src1, VK64WM:$mask, i2048mem:$src2), "GATHER_256B\t{$src2, {$dst} {${mask}}|${dst} {${mask}}, $src2}", [(set VR_2048:$dst, VK64WM:$mask_wb, (v64i32 (masked_gather

Yes, it looks like passing ‘EnableVec’ and ‘EnableSLPVec’ to ‘Args.hasFlag’ should be replaced with ‘false’ and then it has the expected behaviour. MartinO From: cfe-dev [mailto:cfe-dev-bounces at lists.llvm.org] On Behalf Of Martin J. O'Riordan via cfe-dev Sent: 01 March 2018 18:02 To: 'Richard Smith' <richard at metafoo.co.uk> Cc: 'Clang Dev'

Hi, people. Allow me to chat a tiny bit on two vectorisation-related matters, in the context of R. I'm curious about if the following ideas have ever been considered, and rejected already. First is about using the so-called Duff's device for partially unrolling loops. I did not overly check in R sources, and am not familiar with them anyway, but the only usage I saw is within

(please do cc me to preserve thread as i am subscribed digest) Hi folks, i have a requirement to develop a libre licensed low power embedded 3D GPU and VPU and using RISCV as the basis (GPGPU style) seems eminently sensible, and anyone is invited to participate. A gsoc2017 student named Jake has already developed a Vulkan3D software renderer and shader, and (parallelised) llvm is a critical

I've decided to try Zanzarah in both wine 1.2.2 and in latest release 1.3.27 None works... :( Here is the terminal output in 1.3.27: ... DFMT_R8G8_SNORM_L8X8_UNORM to floating point. err:d3d_surface:surface_convert_color_to_float Unhandled conversion from WINED3DFMT_R8G8_SNORM_L8X8_UNORM to floating point. err:d3d_surface:surface_convert_color_to_float Unhandled conversion from

Tom, Let me go a little deeper. Xinmin's answer is correct but a bit over-simplified. There are parts of "legality" and "cost model" that OpenMP SIMD code has to go through, and current LV is rather unclear about it ---- due to historical reasons ---- and I'm trying to resolve them one small step at a time. See

No, I’m wrong. I think that bug is actually in ‘hasFlag’ itself. In ‘llvm/lib/Option/ArgList.cpp’ line #70: bool ArgList::hasFlag(OptSpecifier Pos, OptSpecifier PosAlias, OptSpecifier Neg, bool Default) const { if (Arg *A = getLastArg(Pos, PosAlias, Neg)) return A->getOption().matches(Pos) || A->getOption().matches(PosAlias); return

Please ignore this thread - I got myself confused, the code is fine - too many long days and nights staring at code. There is an issue, but it is different to what I thought. My command line is not: clang -S -O3 -fno-vectorize -fno-slp-vectorize foo.c but: clang -S -fno-vectorize -fno-slp-vectorize -O3 foo.c The difference was subtly hidden in a much longer argument list

Hi Hideki, Thanks for the interesting writeup! > On Aug 27, 2016, at 7:15 AM, Renato Golin via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > On 25 August 2016 at 05:46, Saito, Hideki via llvm-dev > <llvm-dev at lists.llvm.org> wrote: >> Now, I have one question. Suppose we'd like to split the vectorization decision as an Analysis pass and vectorization

Xinmin, > Tom, your understanding is correct per OpenMP SIMD model. Our implementation behaves as you stated. > Which is not part of LLVM main trunk yet. Is that the implementation that is based on the intrinsics in the RFC you and Hal Finkel had sent out to the list? Or is it a different implementation (and if so, is there some plan to merge the two)? Thanks, --Vikram Adve //

I've tried to run demo of Hard Reset and it has two big problems on Wine. First is that mouse isn't working. You get input only from keyboard but that can be solved with raw input patch. I used the one that is working with Deus Ex: Human Revolution: http://dl.dropbox.com/u/6901628/raw2.patch but second is much worse. Basically almost all of the textures aren't rendered. It starts

Hi R guru coders I wrote a bit of code to add a new column onto a "topTable" dataframe. That is a list of genes processed using the limma package. I used a for loop but I kept feeling there was a better way using a more vector oriented approach. I looked at several commands such as "apply", "by" etc but could not find a good way to do it. I have this feeling there

Hi All, I am counting the number of occurrences of the terms listed in one vector in another vector. My code runs: for( i in 1:length(vector3)){ vector3[i] = sum(1*is.element(vector2, vector1[i])) } where vector1 = vector containing the terms whose occurrences I want to count vector2 = made up of a number of repetitions of all the elements of vector1 vector3 = a vector of NAs that is