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by Fr0styMatt 4565 days ago
In what way is using LLVM bitcode (PNaCL) at all similar to ActiveX?

Yeah yeah I get it. I like asm.js as much as the next person; I just wish this whole PNaCl-is-ActiveX meme would seriously go away. It's willful ignorance.

FWIW, I think it's fantastic that asm.js is turning out great. I also think that PNaCl is a worthy technical achievement. Two ways of solving the same problem given different constraints. I think Mozilla has a better chance and agree with their reasoning re- browser compatibility and third-party adoption. Still doesn't mean I'm going to go around calling PNaCl ActiveX when it clearly isn't.
1 comments
johnbm 4565 days ago
Because PNaCl comes with its own implementations of input, graphics, audio, etc and cannot talk to any of the regular Web APIs. So basically, PNaCL is either ActiveX or it's Flash.

https://developers.google.com/native-client/dev/pepperc/grou...

That said, I support using LLVM bitcode more than asm.js myself. I think asm.js is the dying breaths of JavaScript being hailed as its rebirth.

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pcwalton 4565 days ago
> That said, I support using LLVM bitcode more than asm.js myself. I think asm.js is the dying breaths of JavaScript being hailed as its rebirth.

I think asm.js has technical advantages over LLVM bitcode. Neither were really designed for this purpose (for LLVM, you must strip the undefined behavior; for JS, you must strip the high-level semantics), but at least JS has a fully specified, multi-vendor standard specifying the execution semantics. Plus asm.js has a very minimal type system and is non-SSA (while retaining high-level loop constructs that can be easily used to construct SSA without dominance frontiers if needed), both of which I think are advantages for delivering bytecode over the Web.

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johnbm 4558 days ago
That must be why asm.js v0.1 already introduced non-standard language extensions (imul) and has a roadmap full of more. Which browsers does the asm.js of today run on? And which browsers will the asm.js of the future run on?
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haberman 4565 days ago
So providing APIs designed for C and C++ (instead of gluing it to JavaScript APIs) makes PNaCl the same as either an unsandboxed, proprietary, closed-source, non-OS-portable, non-CPU-portable Microsoft technology from the 90s, or a proprietary, closed-source Adobe technlogy from the 2000s?

I think that may be a false dichotomy.

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TazeTSchnitzel 4565 days ago
Well, PNaCl is poorly specified, difficult to implement for other browser vendors, and relies on a single implementation.
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haberman 4565 days ago
> PNaCl is poorly specified

Not sure that's fair: https://developers.google.com/native-client/dev/reference/pn...

But even if all of those things was true, that makes it ok to call it ActiveX? By that logic I can call Firefox IE because it implements extensions to JavaScript that have not (yet) been standardized. But that wouldn't be fair and neither is calling PNaCl ActiveX.

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