JavaScript and HTML are a lot more bloat than machine language code written to the wire.
Writing in a language appropriate to the task is almost always the right tradeoff.
Writing in a language appropriate to the task is almost always the right tradeoff.
http://mozakai.blogspot.com/2011/11/code-size-when-compiling... suggests otherwise in a head-to-head comparison: C code compiled to both a platform-native binary blob and JavaScript, then both gzipped (standard practice for any large JS file on the web).
And if you're talking platform-dependent machine code, that's likely _worse_ on the wire in practice, because unlike a platform-independent representation you can't do edge caching or other sorts of intermediate caches. But maybe you meant a virtual machine (i.e. what people ask for when they want a common bytecode)?
You still need a nontrivial runtime (a la PNaCl) if you're going to provide the sort of sandboxing guarantees for the code people want for code that runs without explicit user opt-in. Or is that a non-goal in your case? In that case, I'd like to understand the problem you're trying to solve, since it sounds different from the one JavaScript in web browsers is solving.
I agree that things like asm.js have a performance hit compared to just running an unsafe binary blob. So does PNaCl (though the hit there is different from the asm.js hit: it has somewhat faster steady-state, but worse startup performance). Again, if you're not talking about something that has the same safety guarantees as JS and PNaCl you're comparing apples to oranges.
But why would you actually do that as a long-term solution? JavaScript isn't an ISA. It's not hard-coded into anything. You don't have to throw away all the existing JavaScript code to start supporting something else in addition to it. All you would have to do is write code to support whatever bytecode you actually want to use and contribute it to the major browsers.
To me, asm.js looks like a bad kludge -- and a great road ahead, just extend it a little bit over the next decade with the stuff compiler writers will clamor for.
Am I missing something?
Compiling other languages to JavaScript is a tolerable transition mechanism while browsers that don't support something better are still popular, but trying to improve the ability of browsers to interpret compiled-to-JavaScript code from other languages is farcical -- if you're going to update the browser then update it to support something better than JavaScript, not to improve the performance of the horrible legacy transition kludge.
But I'm cynical about the possibility to get a new bytecode standard out, without e.g. MS sabotag... extending it. Half the value of asm.js should be that if there is a working system already in place, the motivations for such shenanigans lessens.
The way to handle Microsoft in a situation like this is to ignore them. Support the same IR on Firefox, Chrome and Safari and then Microsoft can play along or go home. At that point the worst they could do is implement an extended version that allows sites made for all browsers to work with IE but then encourage developers to make sites using Windows-specific features that won't work on other platforms. That's effectively what they tried with Silverlight and you see how far that got them.