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Comment by commandlinefan | Hacker News Reader

Well, you can make things run even faster by hand-coding it in assembler... but performance isn't the reason we use high level languages. I agree with you that ignoring performance characteristics in favor of speed-to-market is an awful and pervasive practice in modern software development, but the linked article isn't talking about or making that case at all. He's saying that he can make his own custom object oriented C language that runs faster than C++ itself, but that's not news - people were saying that in 1995 (at least). The maintainability hit isn't worth it.

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This is not his own custom object oriented C language, this is just a very well known idiom for implementing polymorphic functions in C.

It's not really possible to write hand-coded assembler that's faster anymore. C/C++ compilers have deep knowledge of architecture-specific instruction pipelines that allow them to schedule instructions more accurately than any human could.

My most recent misadventure: trying to write hand-coded ARM Neon assembler, and/or C++ code with neon intrinsics to optimize a piece of real-time audio effect code. The clear performance winner: plain C++ with no intrinsics, but tweaked to allow auto-vectorization (plus judicious use of the __restrict modifier for a small but significant boost). GCC produced code that had better instruction scheduling than I could (but not for the NEON intrinsics, oddly). And as an added bonus, the same plain-old C++ code generates AVX vectorization on MSVC without modifications! (MSVC also supports __restrict until the C++ standards committee gets their act together to adopt the eminently necessary C99 restrict keyword).

It is. I witnessed it many times on Code Golf substack.

>It's not really possible to write hand-coded assembler that's faster anymore.

That is wrong. Just because you didn’t succeed in writing faster code in one case, doesn’t mean it’s impossible. See e.g. [1] on why the Lua vm is written in assembly. It’s from 2011 but not much has changed in the meantime.

[1] http://lua-users.org/lists/lua-l/2011-02/msg00742.html

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