Vrmac

nd vice versa, error handling to automatically convert between exceptions and integer status codes at the API boundary, and more. Gonna be very hard to add into the existing language like Java. > "Vector API" JEP That API is not good. They don’t expose hardware instructions, instead they have invented some platform-agnostic API and implemented graceful degradation. This means the applicability is likely to be limited to pure vertical operations processing FP32 or FP64 numbers. The rest of the SIMD instructions are too different between architectures. A simple example in C++ is [2], see [3] for the context. That example is trivial to port to modern C#, but impossible to port to Java even after the proposed changes. The key part of the implementation is psadbw instruction, which is very specific to SSE2/AVX2 and these vector APIs don’t have an equivalent. Apart from reduction, other problematic operations are shuffles, saturating integer math, and some memory access patterns (gathers in AVX2, transposed loads/stores on NEON). > most of these are not done / not in a stable LTS Java release yet BTW, SIMD intrinsics arrived to C# in 2019 (.NET Core 3.0 released in 2019), and unmanaged interop support is available since the very first 1.0 version. [0] https://github.com/Const-me/Vrmac/blob/master/VrmacVideo/Lin... [1] https://github.com/Const-me/Vrmac/blob/master/VrmacVideo/Lin... [2] https://gist.github.com/Const-me/3ade77faad47f0fbb0538965ae7... [3] https://news.ycombinator.com/item?id=36618344

helps with startup performance. This is critical for command-line apps, and very desirable for desktop apps. This is part of Project Valhalla [3], they're adding value types and actual generics, among other things. That said, most of these are not done / not in a stable LTS Java release yet. We'll see how much better it'll be compared to C# (if at all) once they land. [0] https://openjdk.org/jeps/454 [1] https://docs.oracle.com/en/java/javase/21/core/foreign-funct... [2] https://openjdk.org/jeps/460 [3] https://openjdk.org/projects/valhalla/

language itself is very complicated, especially the templates. However, just because something is in the language doesn’t mean it’s a good idea to use it. You don’t need to be familiar with that stuff unless doing something very advanced, like customizing the Eigen C++ library. Don’t follow the patterns found in the standard library: unlike your code, that library has good reasons to use that template BS. If instead of templates you do something else, C++ becomes much easier to use, and most importantly other people will still be able to read and understand your code. Another reason to avoid excessive template metaprogramming, it slows down the compiler, because template-heavy code often needs to be in headers as opposed to cpp files. P.S. If you don’t need extreme levels of performance (defined as “approach the numbers listed in CPU specs”, the numbers are FLOPS or memory bandwidth), and you don’t need the ecosystem too much, consider C# instead of C++. Much faster than Python, often faster than Scala or Java, easy integration with C should you need that (about the same as Rust, much easier than Python or Java), the only downside is these ~100MB of the runtime. The reputation is weird, but technically the language and runtime are pretty good. For example, here’s a C# library which re-implements a subset of ffmpeg and libavcodec C libraries for one particular platform, Linux on Raspberry Pi4: https://github.com/Const-me/Vrmac/tree/master/VrmacVideo