Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.lang.javascript > #24763
| Path | csiph.com!usenet.pasdenom.info!weretis.net!feeder1.news.weretis.net!news.solani.org!.POSTED!not-for-mail |
|---|---|
| From | Thomas 'PointedEars' Lahn <PointedEars@web.de> |
| Newsgroups | comp.lang.javascript |
| Subject | Re: "i = i|0" |
| Date | Thu, 12 Jun 2014 13:35:01 +0200 |
| Organization | PointedEars Software (PES) |
| Lines | 48 |
| Message-ID | <1897109.R5dzFez7A1@PointedEars.de> (permalink) |
| References | <emscripten-20140611221102@ram.dialup.fu-berlin.de> <5398d161$0$6667$9b4e6d93@newsspool3.arcor-online.net> <12993215.vN2ElCmnT9@PointedEars.de> <53998d6b$0$6613$9b4e6d93@newsspool4.arcor-online.net> |
| Reply-To | Thomas 'PointedEars' Lahn <cljs@PointedEars.de> |
| Mime-Version | 1.0 |
| Content-Type | text/plain; charset="UTF-8" |
| Content-Transfer-Encoding | 8Bit |
| X-Trace | solani.org 1402572903 919 eJwFwYkBwEAEBMCW4rAox9t/CZlRBqFNoBA9vSUkX/jzqByjta4qjk93pMdU9g4P4eSvN38qRBGm (12 Jun 2014 11:35:03 GMT) |
| X-Complaints-To | abuse@news.solani.org |
| NNTP-Posting-Date | Thu, 12 Jun 2014 11:35:03 +0000 (UTC) |
| User-Agent | KNode/4.12.4 |
| X-User-ID | eJwFwYEBwCAIA7CXrLSA5yiM/09YInN4BV1OjcaNC8x9A1RNDN/R6XZDj6GU7C7d8gM2vth37VN8kZmf4Qc3FhTc |
| Face | 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 |
| X-Face | %i>XG-yXR'\"2P/C_aO%~;2o~?g0pPKmbOw^=NT`tprDEf++D.m7"}HW6.#=U:?2GGctkL,f89@H46O$ASoW&?s}.k+&.<b';Md8`dH6iqhT)6C^.Px|[=M@7=Ik[_w<%n1Up"LPQNu2m8|L!/3iby{-]A+#YE}Kl{Cw$\U!kD%K}\2jz"QQP6Uqr],./"?;=4v |
| Cancel-Lock | sha1:zTuhjFjZhI9GivbbkYYNrxHNNN0= |
| X-NNTP-Posting-Host | eJwFwYEBwCAIA7CXUCjKObTD/09YAs+VOpHIwMPr0Iwj2E5dF6z27sNr5O4xFuuV9GHJauoHMVoR5Q== |
| Xref | csiph.com comp.lang.javascript:24763 |
Show key headers only | View raw
Christoph Michael Becker wrote: > Thomas 'PointedEars' Lahn wrote: >> Christoph Michael Becker wrote: >>> At least the C semantics are better matched; consider arbitrary input to >>> the function, or an overflow occuring in the calculation. >>> >>> I'm not sure about the performance. Actually, this idiom is quite >>> common, so it might cause performance improvements in some ECMAScript >>> implementations. At least it is used in asm.js to enforce the type of i >>> and the return value to be an integer type. >> >> Unfortunately, you are wrong on all accounts. > > Even if I am wrong on all accounts, I wouldn't call that unfortunate--at > least I could learn from the mistake/misinformation. :) I would rather that you had not been wrong and this mistake by others had been discovered earlier. >> It would appear that at least this Emscripten version (probably asm.js, >> too) is yet another script-kiddie approach that should be avoided, at >> least for all computationally critical uses. > > I wouldn't call Emscripten/asm.js a script-kiddie approach. It seems > asm.js is already supported by all major browsers, and it seems that > there are areas of application where asm.js is mandatory for > performance, e.g. browser games. So much the worse. >> ToInt32(…) is _not_ equivalent to >> C/C++’s “int”. > > Of course. But if I'm not mistaken, there is no ToInt32() involved in > asm.js code, which instead deals with native "int"s. You are missing the point. Native “int”s are *generic*; the “|” algorithm is not. It matters not that asm.js does not use ToInt32(); Emscripten is used to transcompile to asm.js, and Emscripten apparently generates code that uses ToInt32() implicitly; namely, it uses the “|” operator for conversion to pseudo-integer. -- PointedEars FAQ: <http://PointedEars.de/faq> | SVN: <http://PointedEars.de/wsvn/> Twitter: @PointedEars2 | ES Matrix: <http://PointedEars.de/es-matrix> Please do not Cc: me. / Bitte keine Kopien per E-Mail.
Back to comp.lang.javascript | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Re: "i = i|0" Christoph Michael Becker <cmbecker69@arcor.de> - 2014-06-12 00:00 +0200
Re: "i = i|0" Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-06-12 01:04 +0200
Re: "i = i|0" Christoph Michael Becker <cmbecker69@arcor.de> - 2014-06-12 13:22 +0200
Re: "i = i|0" Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-06-12 13:35 +0200
Re: "i = i|0" Christoph Michael Becker <cmbecker69@arcor.de> - 2014-06-12 15:26 +0200
csiph-web