https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88602
--- Comment #3 from Jan Hubicka <hubicka at gcc dot gnu.org> --- In addition to Skia, Firefox gfx library now contains more clang specific vector code: gfx/wr/swgl/src/vector_type.h control vector implementation of some shader rountines (seen in the rasterflood-gradient benchmark). It is part of new rust-based rendering library "WebRender is a GPU-based 2D rendering engine written in [Rust](https://www.rust-lang.org/). [Firefox](https://www.mozilla.org/firefox), the research web browser [Servo](https://github.com/servo/servo), and other GUI frameworks draw with it. It currently uses the OpenGL API internally." however the rendering loops are C++ gfx/ycbcr/yuv_convert.cpp gfx/ycbcr/yuv_row.h gfx/ycbcr/yuv_row_win.cpp this is color space conversion library imported from Chromium: "This color conversion code is from the Chromium open source project available here: http://code.google.com/chromium/ The code comes from svn revision 63840 on 2010-10-26. It has been superseded upstream by libyuv (which is spawned off it). Bug 791941 is about trying to replace this code with libyuv." So it seems that there is now more code that does rely on these extensions. This does show as quite noticeable difference in some rendering benchmarks (up to 500%). Basically these are video rendering, pdf rendering, svg rendering and the rasterfloods.
