compiler-explorer
cppinsights
compiler-explorer | cppinsights | |
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191 | 24 | |
15,198 | 3,555 | |
1.5% | - | |
9.9 | 8.1 | |
about 13 hours ago | 22 days ago | |
TypeScript | C++ | |
BSD 2-clause "Simplified" License | MIT License |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
compiler-explorer
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What if null was an Object in Java?
At least on android arm64, looks like a `dmb ishst` is emitted after the constructor, which allows future loads to not need an explicit barrier. Removing `final` from the field causes that barrier to not be emitted.
https://godbolt.org/#g:!((g:!((g:!((h:codeEditor,i:(filename...
- Ask HN: Which books/resources to understand modern Assembler?
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3rd Edition of Programming: Principles and Practice Using C++ by Stroustrup
You said You won't get "extreme performance" from C++ because it is buried under the weight of decades of compatibility hacks.
Now your whole comment is about vector behavior. You haven't talked about what 'decades of compatibility hacks' are holding back performance. Whatever behavior you want from a vector is not a language limitation.
You could write your own vector and be done with it, although I'm still not sure what you mean, since once you reserve capacity a vector still doubles capacity when you overrun it. The reason this is never a performance obstacle is that if you're going to use more memory anyway, you reserve more up front. This is what any normal programmer does and they move on.
Show what you mean here:
https://godbolt.org/
I've never used ISPC. It's somewhat interesting although since it's Intel focused of course it's not actually portable.
I guess now the goal posts are shifting. First it was that "C++ as a language has performance limitations" now it's "rust has a vector that has a function I want and also I want SIMD stuff that doesn't exist. It does exist? not like that!"
Try to stay on track. You said there were "decades of compatibility hacks" holding back C++ performance then you went down a rabbit hole that has nothing to do with supporting that.
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C++ Insights – See your source code with the eyes of a compiler
C++ Insights is available online at https://cppinsights.io/
It is also available at a touch of a button within the most excellent https://godbolt.org/
along side the button that takes your code sample to https://quick-bench.com/
Those sites and https://cppreference.com/ are what I'm using constantly while coding.
I recently discovered https://whitebox.systems/ It's a local app with a $69 one-time charge. And, it only really works with "C With Classes" style functions. But, it looks promising as another productivity boost.
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Ask HN: How can I learn about performance optimization?
[P&H RISC] https://www.google.com/books/edition/_/e8DvDwAAQBAJ
Compiler Explorer by Matt Godbolt [Godbolt] can help better understand what code a compiler generates under different circumstances.
[Godbolt] https://godbolt.org
The official CPU architecture manuals from CPU vendors are surprisingly readable and information-rich. I only read the fragments that I need or that I am interested in and move on. Here is the Intel’s one [Intel]. I use the Combined Volume Set, which is a huge PDF comprising all the ten volumes. It is easier to search in when it’s all in one file. I can open several copies on different pages to make navigation easier.
Intel also has a whole optimization reference manual [Intel] (scroll down, it’s all on the same page). The manual helps understand what exactly the CPU is doing.
[Intel] https://www.intel.com/content/www/us/en/developer/articles/t...
Personally, I believe in automated benchmarks that measure end-to-end what is actually important and notify you when a change impacts performance for the worse.
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Managing mutable data in Elixir with Rust
Let's compile it with https://godbolt.org/, turn on some optimisations and inspect the IR (-O2 -emit-llvm). Copying out the part that corresponds to the while loop:
4:
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Free MIT Course: Performance Engineering of Software Systems
resources were extra useful when building deeper intuitions about GPU performance for ML models at work and in graduate school.
- CMU's "Deep Learning Systems" Course is hosted online and has YouTube lectures online. While not generally relevant to software performance, it is especially useful for engineers interested in building strong fundamentals that will serve them well when taking ML models into production environments: https://dlsyscourse.org/
- Compiler Explorer is a tool that allows you easily input some code in and check how the assembly output maps to the source. I think this is exceptionally useful for beginner/intermediate programmers who are familiar with one compiled high-level language and have not been exposed to reading lots of assembly. It is also great for testing how different compiler flags affect assembly output. Many people used to coding in C and C++ probably know about this, but I still run into people who haven't so I share it whenever performance comes up: https://godbolt.org/
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Verifying Rust Zeroize with Assembly...including portable SIMD
To really understand what's going on here we can look at the compiled assembly code. I'm working on a Mac and can do this using the objdump tool. Compiler Explorer is also a handy tool but doesn't seem to support Arm assembly which is what Rust will use when compiling on Apple Silicon.
- 4B If Statements
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Operator precedence doubt
Play around with it in godbolt if you're really curious: https://godbolt.org/
cppinsights
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C++ Insights – See your source code with the eyes of a compiler
Sorry, I don't know about an Emacs plugin. All the plugins/extensions I'm aware of are listed in the Readme.md: https://github.com/andreasfertig/cppinsights/#c-insights--vi...
I'm happy to add an entry for Emacs once somebody develops a plugin for that editor.
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C++20 Idioms for Parameter Packs
Thank you! This is exactly the sort of thing I was looking for.
I found the source at https://github.com/andreasfertig/cppinsights
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Why does ![]{} equate to 0?
You can put it into https://cppinsights.io/ and see the conversions that happen under the hood.
- C++ lernen
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BitMasks in 2023
I tried this at https://cppinsights.io/ to see what is generated for something like:
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Ask HN: Best way to learn C++ in 2022
> https://cppinsights.io/ it's a must so you can investigate what gets generated by templates behind the scenes.
> http://eel.is/c++draft/ bookmark this, you will need it!
Now, about books I would suggest the latest "A tour of C++" by Bjarne Stroustrup; it's ideal for experienced programmers that want to learn modern C++ rather fast.
Other books would be Scott Meyers' Effective Series, Andrei Alexandrescu and Herb Sutter are a must, and of course Jason Turner's "C++ Weekly" series [1]; of course apart from the books, the links I have originally shared are more than enough to cover everything around C++.
[1] https://www.youtube.com/c/lefticus1/videos
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Ask HN: Where can I find C++ by Example?
https://cppinsights.io/ it's a must so you can investigate what gets generated by templates behind the scenes.
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Ask HN: Any tool to look C++ interpretation template form syntax to substitution
Try https://cppinsights.io. For example, go to https://cppinsights.io/s/8401262a and click the play button at the top left.
If you're doing something more complex, you might need metashell. See http://metashell.org/manual/how_to/index.html#see-what-templ.... But you have to really, deeply, love C++ to get much out of it.
- Question on a For each loop.
- Can anyone recommend a good book/resource on C++/C++ compilers? With detailed discussions of what happens "under the hood".
What are some alternatives?
C++ Format - A modern formatting library
LLVM-Guide - LLVM (Low Level Virtual Machine) Guide. Learn all about the compiler infrastructure, which is designed for compile-time, link-time, run-time, and "idle-time" optimization of programs. Originally implemented for C/C++ , though, has a variety of front-ends, including Java, Python, etc.
rust - Empowering everyone to build reliable and efficient software.
lsif-clang - Language Server Indexing Format (LSIF) generator for C, C++ and Objective C
format-benchmark - A collection of formatting benchmarks
GSL - Guidelines Support Library
papers - ISO/IEC JTC1 SC22 WG21 paper scheduling and management
gcem - A C++ compile-time math library using generalized constant expressions
rustc_codegen_gcc - libgccjit AOT codegen for rustc
fccf - fccf: A command-line tool that quickly searches through C/C++ source code in a directory based on a search string and prints relevant code snippets that match the query.
firejail - Linux namespaces and seccomp-bpf sandbox
Xoshiro-cpp - Header-only Xoshiro/Xoroshiro PRNG wrapper library for modern C++ (C++17/C++20)