Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-23 Thread Tobias B. Besemer
"[...] The earlier 'SIMD' instruction sets on the x86 platform, from oldest to newest, are 'MMX', '3DNow!' (developed by AMD), 'SSE' and 'SSE2'. [...]" Source: https://en.wikipedia.org/wiki/SSE3 (At the top.) Is support for 'MMX' & '3DNow!' already dropped? -BesTo ___

Re: the looming wasm chasm was Re: Requiring SSE2 on all 32-bit x86 OSs

2016-05-22 Thread Lars Hansen
The baseline compiler has modest needs and should be able to target a simple wasm interpreter fairly easily. --lars On Sun, May 22, 2016 at 11:08 PM, Till Schneidereit < t...@tillschneidereit.net> wrote: > On Sun, May 22, 2016 at 10:43 PM, Cameron Kaiser > wrote: > > > On 5/18/16 10:41 PM, Jan

Re: the looming wasm chasm was Re: Requiring SSE2 on all 32-bit x86 OSs

2016-05-22 Thread Till Schneidereit
On Sun, May 22, 2016 at 10:43 PM, Cameron Kaiser wrote: > On 5/18/16 10:41 PM, Jan de Mooij wrote: > >> They do get the baseline compiler, which can still be significantly >>> faster than the interpreter, but Ion requires SSE2. Since the runtime >>> detection does just turn Ion off altogether, I

the looming wasm chasm was Re: Requiring SSE2 on all 32-bit x86 OSs

2016-05-22 Thread Cameron Kaiser
On 5/18/16 10:41 PM, Jan de Mooij wrote: They do get the baseline compiler, which can still be significantly faster than the interpreter, but Ion requires SSE2. Since the runtime detection does just turn Ion off altogether, I don't know if we would gain much by removing it (the ability to disa

Re: Requiring SSE2 on all 32-bit x86 OSs

2016-05-19 Thread Henri Sivonen
On Thu, May 19, 2016 at 12:31 PM, Mike Hommey wrote: > I don't think anyone suggested to add support for runtime selection of > SSE2 for code that is not inline asm. The code that I'm most immediately interested in replacing with Rust with SSE2 intrinsics without runtime selection currently uses

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-19 Thread Henri Sivonen
On Thu, May 19, 2016 at 12:30 PM, Kurt Roeckx wrote: > On 2016-05-18 10:10, Henri Sivonen wrote: >> >> What do we need to do to reach a decision that it's indeed OK to treat >> *run-time* selection of SSE2 vs. non-SSE2 especially in Rust code as a >> "patches not even welcome" kind of thing, consi

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-19 Thread Kurt Roeckx
On 2016-05-18 10:10, Henri Sivonen wrote: What do we need to do to reach a decision that it's indeed OK to treat *run-time* selection of SSE2 vs. non-SSE2 especially in Rust code as a "patches not even welcome" kind of thing, considering that this may lead to Linux distros shipping an 32-bit x86

Re: Requiring SSE2 on all 32-bit x86 OSs

2016-05-19 Thread Mike Hommey
On Thu, May 19, 2016 at 12:07:42PM +0300, Henri Sivonen wrote: > On Wed, May 18, 2016 at 8:32 PM, Benjamin Smedberg > wrote: > > Can we require SSE2 for Mozilla builds of Firefox for Linux? Yes, I am > > comfortable making that decision today. > > Thank you! I filed > https://bugzilla.mozilla.org

Re: Requiring SSE2 on all 32-bit x86 OSs

2016-05-19 Thread Henri Sivonen
On Wed, May 18, 2016 at 8:32 PM, Benjamin Smedberg wrote: > Can we require SSE2 for Mozilla builds of Firefox for Linux? Yes, I am > comfortable making that decision today. Thank you! I filed https://bugzilla.mozilla.org/show_bug.cgi?id=1274196 for this. > Should we also take actions that preven

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Jan de Mooij
On Thu, May 19, 2016 at 2:59 AM, Emanuel Hoogeveen < emanuel.hoogev...@gmail.com> wrote: > They do get the baseline compiler, which can still be significantly faster > than the interpreter, but Ion requires SSE2. Since the runtime detection > does just turn Ion off altogether, I don't know if we w

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Jan de Mooij
On Thu, May 19, 2016 at 2:59 AM, Emanuel Hoogeveen wrote: > > They do get the baseline compiler, which can still be significantly faster > than the interpreter, but Ion requires SSE2. Since the runtime detection does > just turn Ion off altogether, I don't know if we would gain much by removing

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Emanuel Hoogeveen
On Wednesday, May 18, 2016 at 7:32:38 PM UTC+2, Benjamin Smedberg wrote: > - Our own JITs and their support for non-SSE2 paths > - Our primary JIT doesn't support non-SSE2, right? So these users > already fall back to the slow interpretation path? They do get the baseline compile

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Tobias B. Besemer
Am Mittwoch, 18. Mai 2016 20:28:01 UTC+2 schrieb Tobias B. Besemer: > > If we're going to accidentally keep introducing bugs where non-SSE2 CPUs > > crash, it would be far better to add a runtime check at the beginning of > > main() and error out, than to have a steady trickle of bug reports about

Re: Requiring SSE2 on all 32-bit x86 OSs

2016-05-18 Thread Markus Stange
On 2016-05-18 1:32 PM, Benjamin Smedberg wrote: - Other platform code that does dynamic SSE2 detection. For example, image decoders which we compiler in both SSE2 and non-SSE2 configs currently, and select the codepath at runtime. - I imagine we'd like to remove this complexity fro

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Jim Blandy
On Wed, May 18, 2016 at 9:51 AM, Ralph Giles wrote: > On Wed, May 18, 2016 at 3:54 AM, Mike Hommey wrote: > > > Now, with my Debian hat on, I can tell you with 100% certainty that > > angry Debian users *will* come with patches and will return even > > angrier if patches are not even welcome. >

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Tobias B. Besemer
> If we're going to accidentally keep introducing bugs where non-SSE2 CPUs > crash, it would be far better to add a runtime check at the beginning of > main() and error out, than to have a steady trickle of bug reports about > crashes on illegal instructions which end up being marked INVALID. Thin

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Ralph Giles
On Wed, May 18, 2016 at 11:10:30AM +0300, Henri Sivonen wrote: >> So we now require SSE2 on [...] >> * 32-bit x86 Mac, which means just the plugin-container now that we >> no longer support 10.6, which was the last OS X version that ran on >> 32-bit hardware. Actually, all of Apple's intel hardw

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Benjamin Smedberg
On Wed, May 18, 2016 at 6:54 AM, Mike Hommey wrote: > Henri Sivonen wrote: > > > It seems that we are almost ready to require SSE2 for Mozilla-built > > Firefox for 32-bit x86 Linux. > There are a couple of interrelated issues here. Can we require SSE2 for Mozilla builds of Firefox for Linux?

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Jim Blandy
I think we need to admit that there isn't any rational, analytical way to compare most of the costs here. The one number we *do* have, the number of users who can't upgrade, is kind of tantalizing us, but we can't quantify how many users we'll gain by requiring SSE2, how many other bugs we'll fix b

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Tobias B. Besemer
Am Mittwoch, 18. Mai 2016 16:52:25 UTC+2 schrieb Boris Zbarsky: > On 5/18/16 7:38 AM, Tobias B. Besemer wrote: > > Is this really a discussion if Firefox should support CPUs older then 13-15 > > years ??? > > More or less, yes. > > > I can't imagine any scenario were a user needs to run a Pentiu

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Boris Zbarsky
On 5/18/16 7:38 AM, Tobias B. Besemer wrote: Is this really a discussion if Firefox should support CPUs older then 13-15 years ??? More or less, yes. I can't imagine any scenario were a user needs to run a Pentium III with GUI and a browser on it... There were AMD CPUs newer than that wit

Re: Requiring SSE2 on all 32-bit x86 OSs

2016-05-18 Thread Mike Hoye
On 2016-05-18 7:38 AM, Tobias B. Besemer wrote: N00b question: Is this really a discussion if Firefox should support CPUs older then 13-15 years ?? Right now Firefox supports users on platforms their creators have long abandoned - WinXP, pre-SSE2 CPUs, OSX 10.6-8, older Android. Firefox is the

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Tobias B. Besemer
Am Mittwoch, 18. Mai 2016 13:56:14 UTC+2 schrieb Tobias B. Besemer: > Am Mittwoch, 18. Mai 2016 13:38:58 UTC+2 schrieb Tobias B. Besemer: > > N00b question: > > Is this really a discussion if Firefox should support CPUs older then 13-15 > > years ??? > > > > https://en.wikipedia.org/wiki/SSE2 > >

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Tobias B. Besemer
Am Mittwoch, 18. Mai 2016 13:38:58 UTC+2 schrieb Tobias B. Besemer: > N00b question: > Is this really a discussion if Firefox should support CPUs older then 13-15 > years ??? > > https://en.wikipedia.org/wiki/SSE2 > > I can't imagine any scenario were a user needs to run a Pentium III with GUI

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Tobias B. Besemer
N00b question: Is this really a discussion if Firefox should support CPUs older then 13-15 years ??? https://en.wikipedia.org/wiki/SSE2 I can't imagine any scenario were a user needs to run a Pentium III with GUI and a browser on it... ...would mean that the system not only runs not e.g. as a p

Re: Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Mike Hommey
On Wed, May 18, 2016 at 11:10:30AM +0300, Henri Sivonen wrote: > On Mon, May 16, 2016 at 8:53 PM, Benjamin Smedberg > wrote: > > On Mon, May 16, 2016 at 8:47 AM, Henri Sivonen wrote: > >> For clarification: Does this decision apply to 32-bit x86 Linux as > >> well? (It would be sad to have to sup

Requiring SSE2 on all 32-bit x86 OSs (was: Re: Reverting to VS2013 on central and aurora)

2016-05-18 Thread Henri Sivonen
On Mon, May 16, 2016 at 8:53 PM, Benjamin Smedberg wrote: > On Mon, May 16, 2016 at 8:47 AM, Henri Sivonen wrote: >> For clarification: Does this decision apply to 32-bit x86 Linux as >> well? (It would be sad to have to supply and maintain non-SSE2 x86 >> code paths just for Linux.) > > Nobody a