Investigate Dataview usage for typed arrays == 2 about emscripten

[Dandandan]

hmmm... still not implemented in Firefox
bug:
https://bugzilla.mozilla.org/show_bug.cgi?id=575688

[kripken]

I don't think it's implemented in Safari or Opera either. But in any case it would be interesting to do a benchmark to see if this is indeed fast. And if so, adding code to Emscripten to support it as an option would not be hard.

I wonder though if it will be. These are function calls, not indexings, which is a different kind of optimization for JS engines, that I suspect they don't do as well on. Making this fast isn't normal function call inlining either, it's inlining of native code into JS. I don't think any JS engine does that (things like PyPy do, though).

Also, there is the Binary Data proposal for JS, which would provide something similar to this. Firefox for example is starting to implement it. So it's not clear to me what the future of binary data access is, at the moment...

[Dandandan]

I did a test in v8, was a little (few %) bit slower than array + bitshifting.