Issue metadata
Sign in to add a comment
|
Use the most appropriate -mfpu option when building for ARM devices |
||||||||||||||||||||||
Issue descriptionarm.gni always sets arm_fpu to "neon" if arm_use_neon == true. GCC accepts other values like "crypto-neon-fp-armv8" as -mfpu, so we should use the most appropriate one. https://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html#index-mfpu-1624
,
Dec 2 2016
Chrome side CL: https://codereview.chromium.org/2546033002/
,
Dec 5 2016
The following revision refers to this bug: https://chromium.googlesource.com/chromium/src.git/+/e90481d12da0f6b26e5fa541d111ae4e5b9f9022 commit e90481d12da0f6b26e5fa541d111ae4e5b9f9022 Author: hashimoto <hashimoto@chromium.org> Date: Mon Dec 05 04:20:27 2016 gn: Make arm_fpu configurable Chrome OS needs to use values like neon-vfpv4 or crypto-neon-fp-armv8. BUG=670541 Review-Url: https://codereview.chromium.org/2546033002 Cr-Commit-Position: refs/heads/master@{#436231} [modify] https://crrev.com/e90481d12da0f6b26e5fa541d111ae4e5b9f9022/build/config/arm.gni
,
Dec 19 2016
Is there a noticeable performance gained by this change, or is it just cleanup?
,
Dec 19 2016
,
Dec 19 2016
The following revision refers to this bug: https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/4341948bf829e486fdc319733b563ff37a00d431 commit 4341948bf829e486fdc319733b563ff37a00d431 Author: Ryo Hashimoto <hashimoto@chromium.org> Date: Fri Dec 16 04:49:19 2016 chromeos-chrome: Explicitly set arm_fpu and arm_tune BUG=chromium:670541 TEST=build Change-Id: Ie68a887102bbf8968395278fc33154b0c89ee637 Reviewed-on: https://chromium-review.googlesource.com/421347 Commit-Ready: Douglas Anderson <dianders@chromium.org> Tested-by: Ryo Hashimoto <hashimoto@chromium.org> Reviewed-by: Mike Frysinger <vapier@chromium.org> [modify] https://crrev.com/4341948bf829e486fdc319733b563ff37a00d431/chromeos-base/chromeos-chrome/chromeos-chrome-9999.ebuild
,
Dec 20 2016
This is mainly for cleanup. Currently, we feed MARCH_TUNE (which may contain a -mfpu flag like "neon-vfpv4") to Chrome's GN as extra CXXFLAGS/CFLAGS argument, but Chrome's arm.gni always appends -mfpu=neon so now we are feeding multiple contradicting FPU flags to the compiler. Change referred by comment #6 is to fix this. Also, I'd like to change veyron's make.conf to replace ARM_FPU=neon with ARM_FPU=neon-vfpv4 so that the compiler can use vfpv4 instructions (e.g. vfma) when appropriate. This may result in performance gain, but I'm not sure if it's going to be noticeable.
,
Dec 20 2016
The following revision refers to this bug: https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/b0f4c9fd293889da2bb4a3dd55743a9654fecbec commit b0f4c9fd293889da2bb4a3dd55743a9654fecbec Author: Douglas Anderson <dianders@chromium.org> Date: Tue Dec 20 17:15:55 2016 Revert "chromeos-chrome: Explicitly set arm_fpu and arm_tune" This reverts commit 4341948bf829e486fdc319733b563ff37a00d431. This appears to be causing problems. See: chromium:675978 BUG= chromium:675978 , chromium:670541 TEST=Compile Chrome Change-Id: Idce4779b8f3061c71ea6bd1ddfce1b92122b2664 Reviewed-on: https://chromium-review.googlesource.com/422416 Tested-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Mike Frysinger <vapier@chromium.org> [modify] https://crrev.com/b0f4c9fd293889da2bb4a3dd55743a9654fecbec/chromeos-base/chromeos-chrome/chromeos-chrome-9999.ebuild
,
Sep 7
|
|||||||||||||||||||||||
►
Sign in to add a comment |
|||||||||||||||||||||||
Comment 1 by hashimoto@chromium.org
, Dec 2 2016