Please file an issue on the asm.js repo https://github.com/dherman/asm.js
and we'll discuss there. I don't know offhand why Math.round is not in the spec, I agree it does seem like it should be. - Alon On Fri, Apr 18, 2014 at 5:31 PM, Soeren Balko <[email protected]> wrote: > In trying to squeeze out more performance from the project I ported to JS > using emscripten, I have recently focused on finding calls from asm.js-ed > code into non-asm.js functions and then asm.js-ify these functions, if > possible. Among these functions, my code frequently invokes rint and > llrint, which currently live in library.js as non-asm.js functions and use > Math.round internally. That is to say, even though Math.round behaves > similar to rint, it is different in some edge cases, which is why rint > calls cannot simply be replaced by Math.round. > > I tried to asm.js-ify rint and figured that Math.round is actually not > part of the asm.js "standard library". In order to work around this, I > tried using the native musl implementation of rint and have emscripten > compile it into asm.js. While this works in principle, it does not give me > the performance improvement I was hoping for. Actually, I even see a minor > performance degradation (Firefox Nightly). This has probably to do with the > fact that Math.round is quite optimized, whereas asm.js code does not quite > reach native performance. In other words, the performance degradation of > using the compiled native rint function from musl negatively outweighs the > performance penalty of calling from asm.js into the non-asm.js rint > function. > > Naturally, this makes me wonder why Math.round is not supported by asm.js > and if there are plans to add it sometime soon. > > Soeren > > -- > You received this message because you are subscribed to the Google Groups > "emscripten-discuss" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "emscripten-discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
