conan-center-index VS std-simd

Conan is a package manager for C/C++. See: https://conan.io/.

The way it works is that you can provide "recipes", which are Python scripts, that automate the process of collecting source code (usually from a remote Git repository, or a remote source tarball), patching it, making its dependencies and transitive dependencies available, building for specific platform and architecture (via any number of build systems), then packaging up and serving binaries. There's a lot of complexity involved.

Here are the two recipes I mentioned:

libcurl: https://github.com/conan-io/conan-center-index/blob/master/r...

OpenSSL v3: https://github.com/conan-io/conan-center-index/blob/master/r...

Now, for the sake of this thread I want to highlight three things here:

- Conan recipes are usually made by people unaffiliated with the libraries they're packaging;

- The recipes are fully Turing-complete, do a lot of work, have their own bugs - therefore they should really be treated as software comonents themselves, for the purpose of OSS clearing/supply chain verification, except as far as I know, nobody does it;

- The recipes can, and do, patch source code and build scripts. There's supporting infrastruture for this built into Conan, and of course one can also do it by brute-force search and replace. See e.g. ZLib recipe that does it both at the same time:

https://github.com/conan-io/conan-center-index/blob/7b0ac710... -- `_patch_sources` does both direct search-and-replace in source files, and applies the patches from https://github.com/conan-io/conan-center-index/tree/master/r....

Now, good luck keeping track of what's going on there.

Just checkout ConanCenter https://conan.io/center it's free.

https://github.com/conan-io/conan-center-index there's 200+ PR that need reviewing :) we add community reviewers fairly often

As for ffmpeg it was last updated 10 days ago https://github.com/conan-io/conan-center-index/commits/master/recipes/ffmpeg/all :)

This is a more complicated recipe https://github.com/conan-io/conan-center-index/blob/master/recipes/pcapplusplus/all/conanfile.py

You can use the Conan package manager with prebuilt binaries/libraries

https://conan.io/center

It's available in Conan too https://github.com/conan-io/conan-center-index/tree/master/recipes/crowcpp-crow though it's not well maintained so no promises if it's working

You need something like https://conan.io/center/ to install the dependencies. You're lucky because it works well with CMake.

This post on github contains a list of packages supported by conan 2.0, its also kept up to date https://github.com/conan-io/conan-center-index/discussions/16196

Use a package manager: https://vcpkg.link/ https://conan.io/center/

neither proposing nor taking a position on this possible addition)

> ... For completeness we would also like to add that a serious issue is that C still lacks vector operations.

Those are good points. The authors don't take a stance on it, but I do think that syntax for packed structs should be standardized. IMO, so should syntax for inline assembly (both as optional features). These are already common extensions; this is exactly what they should standardize. The additions of "typeof" and #embed are also good examples of this (they had been talking about adding #embed since 1995 [1]).

As for vector instructions, I'm unsure how it could be implemented in a standard way, but I'm not against it. Maybe something like this [2], but with the syntax changed for C instead of C++.

[1]: https://groups.google.com/g/comp.std.c/c/zWFEXDvyTwM

[2]: https://github.com/VcDevel/std-simd

Interesting, thanks for sharing :)

At the time we open-sourced Highway, the standardization process had already started and there were some discussions.

I'm curious why stdlib is the only path you see to default? Compare the activity level of https://github.com/VcDevel/std-simd vs https://github.com/google/highway. As to open-source usage, after years of std::experimental, I see <200 search hits [1], vs >400 for Highway [2], even after excluding several library users.

But that aside, I'm not convinced standardization is the best path for a SIMD library. We and external users extend Highway on a weekly basis as new use cases arise. What if we deferred those changes to 3-monthly meetings, or had to wait for one meeting per WD, CD, (FCD), DIS, (FDIS) stage before it's standardized? Standardization seems more useful for rarely-changing things.

1: https://sourcegraph.com/search?q=context:global+std::experim...

2: https://sourcegraph.com/search?q=context:global+HWY_NAMESPAC...

std-simd - 451 GH stars

Bad news. For SIMD there are not cross-platform intrinsics. Intel intrinsics map directly to SSE/AVX instructions and ARM intrinsics map directly to NEON instructions.

For cross-platform, your best bet is probably https://github.com/VcDevel/std-simd

There's https://eigen.tuxfamily.org/index.php?title=Main_Page But, it's tremendously complicated for anything other than large-scale linear algebra.

And, there's https://github.com/microsoft/DirectXMath But, it has obvious biases :P

But after I worked with auto-vectorization(I wrote about that in part 2), I decided to switch and try myself by adding intrinsics if I was able. You can track my progress here:https://github.com/VcDevel/std-simd/pull/35

STD-SIMD it's almost the same project I was working, but a bit advance https://github.com/VcDevel/std-simd.

If you are worried about Intel vs Arm vs whatever, use https://github.com/VcDevel/std-simd

or https://github.com/KhronosGroup/Vulkan-Hpp which help quite a bit. Or https://github.com/VcDevel/std-simd.

If you want GUIs, same, you have at least (but not only) Qt or WxWidgets.

Want to interface scripting? Pybind11, Boost.Python, WrenBind17 for Wren, Sol2 for Lua... and all things that interface to C work also if you feel brave...

I really think that when it is about getting the job done... C++ goes a long way towards the task.

This is my 20 year experience of C++, almost 13 of those years professionally. Now, back to read the paper. :)

... I just checked your link and wouldn't say that any of these languages have SIMD more than C++ has it currently -

- Java: incubation stage (how is that different from https://github.com/VcDevel/std-simd). Also Java is only getting it soonish for... amd64 and aarch64 ??