Fantastic tail calls, and how to implement them | Lobsters

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Fantastic tail calls, and how to implement them ☶ wasm medium.com
via doug-moen 6 months ago | archive
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WASM is close to standardizing tail calls. It just needs a second web browser implementation, which is in this PR: https://github.com/WebKit/WebKit/pull/2065

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doug-moen 6 months ago | link
Tail call support in WASM is exciting news if you are using C, C++, Zig to generate your WASM. Even though tail call is not yet in the C, C++ standards, Clang has a musttail attribute that forces a function call to be compiled as a tail call, and this feature now has some important use cases.
- Not only can tail calls make C++20 coroutines more efficient, but in fact clang is not able to compile C++20 coroutines without tail call support.
- Parsing Protobuf at 2+GB/s: How I Learned To Love Tail Calls in C
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  carlop 6 months ago | link
  
  Thanks for sharing the article on parsing Protobuf with musttail, very insightful.
  
  I am also very exited on tail calls to move forward, I am somehow biased since it’s a colleague that did the JSC work. Standardization side obviously there might still be many months ahead before things are properly finalized, but I think it’s a welcome step forward.
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    0x2ba22e11 6 months ago | link
    
    It was submitted here a while ago. Here’s the discussion, in case you want to see the comments it got then. https://lobste.rs/s/ffssdz/parsing_protobuf_at_2_gb_s_how_i_learned