<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - GCC memory starvation caused by flatten attribute with LTO" href="https://bugs.freedesktop.org/show_bug.cgi?id=77580#c5">Comment # 5</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - GCC memory starvation caused by flatten attribute with LTO" href="https://bugs.freedesktop.org/show_bug.cgi?id=77580">bug 77580</a> from <a class="email" href="mailto:doctorwhoguy@gmail.com" title="Patrick McMunn <doctorwhoguy@gmail.com>"> Patrick McMunn</a> <pre>Created <a href="attachment.cgi?id=125089" name="attach_125089" title="Patch to allow LTO optmization of xf86-video-intel">attachment 125089</a> <a href="attachment.cgi?id=125089&action=edit" title="Patch to allow LTO optmization of xf86-video-intel">[details]</a> <a href='page.cgi?id=splinter.html&bug=77580&attachment=125089'>[review]</a> Patch to allow LTO optmization of xf86-video-intel I'm attaching a patch that takes a somewhat simpler approach to disabling "flatten" and "force_inline" which cause problems with LTO. I used glxgears to measure FPS. The system was a Pentium 4 with an integrated 845G graphics chip, so it's pretty underpowered hardware, hence the low FPS. Without LTO, I got ~19.5 FPS running glxgears at fullscreen at 1680x1050 resolution. With LTO, I got about 22.5 FPS. That may not seem like much, but that's a 10% performance improvement! Except for the LTO-related flags, I used the same compiler and linker flags during compilation. flags used during compilation: CFLAGS="-O2 -march=pentium4 -pipe -fdevirtualize-speculatively ${LTO}" CXXFLAGS="${CFLAGS}" LDFLAGS="-Wl,-O1 -Wl,--as-needed -Wl,--enable-new-dtags -Wl,--sort-common -Wl,--sort-section=name -Wl,-Bsymbolic-functions -Wl,-z,combreloc ${CXXFLAGS}"</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>