search for: interleaver

Michael Smith wrote: >Whilst I accept that there are many good uses for chunked data, I >think the transformation is trivial, particularly given certain >characteristics of the Ogg container. Remember, the data, if you read >an ogg stream into memory, is _already_ likely to be non-contiguous, >due to ogg's structure. It's trivial, and has insignificant additional

Hi Michael, Sometime back I did some experiments with interleave vectorizer and did not found any degrade, probably my tests/benchmarks are not extensive enough to cover much. Elina is the right person to comment on it as she already experienced cases where it hinders performance. For interleave vectorizer on X86 we do not have any specific costing, it goes to BasicTTI where the costing is not

Hi all, The remaining issue to be decided for the OggPCM2 spec is the support of chunked vs interleaved data. Just so that everyone understands what we are talking about, consider a stereo file that gets stored as an OggPCM file. Within an OggPCM packet, the audio samples for the left and right channels can be stored as interleaved where the samples would be: l0, r0, l1, r1, ..... lN, rN

Regarding InterleavedAccessPass - sure, but proper strided/interleaved access optimization ought to have a positive impact even without target support. Case in point - Hal enabled it on PPC last September. An important difference vs. x86 seems to be that arbitrary shuffles are cheap on PPC, but, as I said below, I hope we can enable it on x86 with a conservative cost function, and still get

Interleaved access is not enabled on X86 yet. We looked at this feature and got into conclusion that interleaving (as loads + shuffles) is not always profitable on X86. We should provide the right cost which depends on number of shuffles. Number of shuffles depends on permutations (shuffle mask). And even if we estimate the number of shuffles, the shuffles are not generated in-place. Vectorizer

Suppose one has x <- c(1, 2, 7, 9, 14) y <- c(71, 72, 77) How would one write an R function which alternates between elements of one vector and the next? In other words, one wants z <- c(x[1], y[1], x[2], y[2], x[3], y[3], x[4], y[4], x[5], y[5]) I couldn't think of a clever and general way to write this. I am aware of gdata::interleave() but it deals

Hello, We would like to propose making LoopVectorize aware of SLP operations, to improve the generated code for loops operating on struct fields or doing complex math. At the moment, LoopVectorize uses interleaving to vectorize loops that operate on values loaded/stored from consecutive addresses: vector loads/stores are generated to combine consecutive loads/stores and then shufflevector

On 26 May 2016 at 19:12, Sanjay Patel via llvm-dev <llvm-dev at lists.llvm.org> wrote: > Is there a compile-time and/or potential runtime cost that makes > enableInterleavedAccessVectorization() default to 'false'? > > I notice that this is set to true for ARM, AArch64, and PPC. > > In particular, I'm wondering if there's a reason it's not enabled for

Hi Florian! This proposal sounds pretty exciting! Integrating SLP-aware loop vectorization (or the other way around) and SLP into the VPlan framework is definitely aligned with the long term vision and we would prefer this approach to the LoopReroll and InstCombine alternatives that you mentioned. We prefer a generic implementation that can handle complicated cases to something ad-hoc for some

I would like to propose that loop pragma `vectorize(disable)` actually means disabling the vectorizer for that loop. This perhaps sounds really obvious (I hope it does), but currently `vectorize(disable)` sets the vectorization width to 1, and that means the vectorizer will run and could perform other tricks such as interleaving. The main reason to change the behaviour is that it will be more what

Hello everyone, I tried to compress audio with opus-1.3.1/src/opus_demo.c recently, which works fine on mono and stereo data . Now I want to compress interleaved 7 channels pcm/wav ( recorded by Microphone array :6mic+ 1reference signal ) with opus, But I have not found an interface that compress multi-channels pcm/wav. 1、Is there a multi-channel compression interface can be used in my case? If

Dear LLVMdev, I've noticed an unusual behavior of the LLVM x86 code generator (with default options) that results in nearly a 4x slow-down in floating-point throughput for my microbenchmark. I've written a compute-intensive microbenchmark to approach theoretical peak throughput of the target processor by issuing a large number of independent floating-point multiplies. The distance

So turns out it is a full reproducer after all (choosing to vectorize on AVX), good. > The details are in PR29025. Interesting. (So we should carefully insert unconditional branches inside shuffle sequences, eh? ;-) > But if we modify the program by adding "*out++ = 0" right after "*out++ = q;" (thus eliminating the pesky <12 x i8>), we get: Indeed such

Note: This is a continuation of a discussion over at https://reviews.llvm.org/D26869. Hi all, In a discussion over on llvm-commits, we are debating how best to test loop vectorization transformations that are guided by the cost model. The cost model is currently used primarily for determining the vectorization and interleave factors. Both of these parameters are easily overridden with command

Thanks Ayal! On Wed, Aug 17, 2016 at 2:14 PM, Zaks, Ayal <ayal.zaks at intel.com> wrote: > Hi Michael, > > > > Don’t quite have a full reproducer for you yet. You’re welcome to try and > see what’s happening in 32 bit mode when enabling interleaving for the > following, based on “https://en.wikipedia.org/wiki/YIQ#From_RGB_to_YIQ”: > > > > void rgb2yik

Thanks Ayal! I'll take a look at DENBench. As another data point - I tried enabling this on our internal benchmarks. I'm seeing one regression, and it seems to be a regression of the "good" kind - without interleaving we don't vectorize the innermost loop, and with interleaving we do. The vectorized loop is actually significantly faster when benchmarked in isolation, but in

> Unfortunately the ALSA API defines a number of formats which are > in practice extremely rare. In particular, any unsigned int format > larger than 8 bits. For instance, the only unsigned int type that > libsndfile supports is unsigned 8 bit. I expected this, it just seemed like a good starting point to get more than 7 formats on the table. Specifically I wanted to the logarithmic

On 11/15/05, Erik de Castro Lopo <mle+xiph@mega-nerd.com> wrote: > Hi all, > > The remaining issue to be decided for the OggPCM2 spec is the support > of chunked vs interleaved data. I think interleaved is the obvious choice - that's what most audio applications are used to dealing with, it's what we need to feed to audio hardware in the end usually, etc. Whilst I

Hi Jerry I'm still able to recreate failures in with 2.2.4 when interleaving file creation/writing from W2k and NT4 machines to a Samba server. I orginally reported this in 2.2.2a, also 2.2.3: http://lists.samba.org/pipermail/samba/2001-December/063396.html http://lists.samba.org/pipermail/samba/2002-January/063483.html http://lists.samba.org/pipermail/samba/2002-February/067221.html I sent

Anyone know if it''s possible to interleave two IP packets when using PPPoA and VC based lines? Can it be done with any PPPoE implementations? The goal is to reduce the delay when you have a high priority packet waiting, but a lower priority (large) packet already started going out ahead of this packet. I don''t want the overhead of much smaller MTU, which is the other way