On Wed, Nov 16, 2011 at 2:58 PM, Pandu Poluan <pa...@poluan.info> wrote: > > On Nov 16, 2011 2:26 PM, "Michael Mol" <mike...@gmail.com> wrote: >> >> On Wed, Nov 16, 2011 at 2:11 AM, Stéphane Guedon <steph...@22decembre.eu> >> wrote: >> > On Wednesday 16 November 2011 02:07:12 Pandu Poluan wrote: >> >> And if you're adventurous, add USE "graphite", reemerge gcc, and >> >> reemerge >> >> world :) >> > >> > what does "graphite" add ? >> >> Thanks for reminding me; I meant to look it up when I got home. >> >> shortcircuit:1@serenity~ >> Wed Nov 16 02:16 AM >> !501 #1 j0 ?0 $ euse -i graphite >> global use flags (searching: graphite) >> ************************************************************ >> no matching entries found >> >> local use flags (searching: graphite) >> ************************************************************ >> >> [snip] >> >> [- ] graphite >> sys-devel/gcc: Add support for the framework for loop optimizations >> based on a polyhedral intermediate representation >> >> So, a new, experimental optimization model and framework inside your >> compiler. If it's specifically for optimizing on loops, I'll venture a >> guess it's going to be mostly effective for graphics libraries and >> apps. I've got some slightly riskier educated guesses on how it works >> and what some numeric side effects and consequences might be, but they >> scare me, so I think I'll leave it to someone who actually knows more >> about it... >> > > I've been using USE "graphite" since gcc-4.5.3-r1 appeared. Upstream says > that graphite is stable, feature-complete, and production-ready since 4.5.3. > > To fully taste the effect of graphite, I even went the torturous route of > emerging gcc + libtool + binutils (in that order) twice, followed by a > wholesale-rebuild of everything (emerge --emptytree), then tarballed the > result to my own "stage3.1" tarball to spare me the *huge* amount of time > required. > > I've deployed 3 systems with USE "graphite", and they *felt* snappier. > emerge's *felt* slower, though. (no objective tests, I know). > > I use Gentoo as a gatewall, and there I did a wholesale-rebuild one more > time, this time specifying CFLAGS "-march=native"... and I just couldn't be > happier with the resulting performance :-) > > Rgds, >
I might be wrong but don't you need to have the gcc's options for graphite enabled to actually make use of the graphite framework? (You might be using them but you haven't mentioned it.) //Fredric //Fredric
