A quick update about performance: ThinLTO and PGO were enabled for our clang-cl builds over the last few weeks. These optimizations have cancelled the previous regressions and brought clang well ahead of MSVC: https://treeherder.mozilla.org/perf.html#/compare?originalProject=try&originalRevision=2adb3cb404ad&newProject=try&newRevision=5336df94a9ce&framework=1 To call out a few: Speedometer scores increased by 6% on Win64 and 12% on Win32, and the most dramatic improvement was displaylist_mutate at 27%!
As far as I'm aware, no blockers have come up and clang-cl is still looking good for the 63 train. On Tue, Jul 10, 2018 at 4:29 PM David Major <dma...@mozilla.com> wrote: > > Bug 1443590 is switching our official Windows builds to use clang-cl > as the compiler. > > Please keep an eye out for regressions and file a blocking bug for > anything that might be fallout from this change. I'm especially > interested in hearing about the quality of the debugging experience. > > It's possible that the patch may bounce and we'll go back and forth to > MSVC for a while. You can check your build's compiler at > `about:buildconfig`. Treeherder is running an additional set of MSVC > jobs on mozilla-central to make sure we can fall back to a green MSVC > if needed. > > Watch for more toolchain changes to come. The next steps after this > will be to switch to lld-link and enable ThinLTO. That will open the > door to a cross-language LTO that could inline calls between Rust and > C++. In the longer term we can look into cross-compiling from Linux. > > But for now, shipping our most-used platform with an open-source > compiler is a huge milestone in and of itself. Big thanks to everyone > who has contributed to this effort on the Mozilla side, and also big > thanks to the developers of LLVM and Chromium who helped make clang on > Windows a realistic possibility. _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
