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Comment by YZF | Hacker News Reader

I'm not super familiar with Rust, do you have SSE/AVX intrinsics (others?)? Can you write assembly embedded in Rust code? How does rust stack in terms of performance?

https://benchmarksgame-team.pages.debian.net/benchmarksgame/...

looks quite decent, but overall Rust is still behind? So if I am in an area where performance (or cost/energy) is king then I'd still pick C++.

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Rust's std::simd is the portable abstraction but it is so far only available in nightly Rust, in principle you would be able to write code that does SIMD on whatever hardware (ARM, x86-64, whatever) is targeted including AVX.

Yes, Rust has inline assembly in roughly the same way you'd be used to with C or C++

https://doc.rust-lang.org/reference/inline-assembly.html

The Benchmarks Game has a bunch of benchmarks, and while it's probably significant that the Python programs are routinely orders of magnitude slower than say C, we likely shouldn't read too much into whether somebody scraped a few more milliseconds off the best time for one of the benchmarks listed.

Portable abstractions for SIMD aren't very useful, because if you're writing SIMD you want performance, and the things it abstracts over (specific SIMD capabilities and weird performance quirks of different instructions) mean the results of using it aren't predictable.

SIMD intrinsics exist, although currently require nightly compiler on non-x86 targets: https://doc.rust-lang.org/1.29.0/core/arch/x86/index.html

Inline assembly: https://rust-lang.github.io/rfcs/2873-inline-asm.html

Performance is almost identical, even the linked benchmark is quite even.

> Can you write assembly embedded in Rust code?

Yes... unlike in x64 MSVC, one of several C++ compilers I frequently must support, where inline assembly is verbotten. Does that put Rust ahead? :P

I don't know the answers to all of your questions, but

>Can you write assembly embedded in Rust code?

Yes, I've done this several times. It looks like this: https://doc.rust-lang.org/rust-by-example/unsafe/asm.html

> do you have SSE/AVX intrinsics (others?)?

Yes. https://docs.rs/simd/latest/simd/

> Can you write assembly embedded in Rust code?

Also yes. https://doc.rust-lang.org/reference/inline-assembly.html

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