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chromium / chromium / src.git / 6cc154e0312d0e8042052c5d04122360028d4f4b
commit6cc154e0312d0e8042052c5d04122360028d4f4b[log] [tgz]
authorBruce Dawson <[email protected]>Tue Apr 12 20:39:49 2022
committerChromium LUCI CQ <[email protected]>Tue Apr 12 20:39:49 2022
tree20097b03749e717ca7848179dc347ca552dd65ad
parent1cc83f6a3ef2d3f9983023c8a585b74e0686adff [diff]
Make CheckForIncludeGuards ~100x faster

This takes CheckForIncludeGuards from being the most expensive presubmit
to being quite unremarkable.

CheckForIncludeGuards uses "if not f.OldContents()" to see whether a
file is new or not. It turns out that this is a fairly expensive
function. At the very least it has to retrieve the contents of the old
file and then call .splitlines() on it, which is a lot of work when all
that matters is whether the file exists or not.

A faster DoesOldContentsExist() function would be nice but is not even
needed because the check that follows is almost never True. So,
reversing the order of the checks gets rid of ~99.9% of the calls to
OldContents(), thus taking CheckForIncludeGuards()'s execution time when
run on all files from about 50 minutes to about half a minute.

Bug: 1309977
Change-Id: I848db84e67384830cda4fcfcc50d6bb13e7830ea
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3583076
Reviewed-by: Erik Staab <[email protected]>
Commit-Queue: Bruce Dawson <[email protected]>
Cr-Commit-Position: refs/heads/main@{#991709}
1 file changed
tree: 20097b03749e717ca7848179dc347ca552dd65ad
  1. android_webview/
  2. apps/
  3. ash/
  4. base/
  5. build/
  6. build_overrides/
  7. buildtools/
  8. cc/
  9. chrome/
  10. chromecast/
  11. chromeos/
  12. codelabs/
  13. components/
  14. content/
  15. courgette/
  16. crypto/
  17. dbus/
  18. device/
  19. docs/
  20. extensions/
  21. fuchsia/
  22. gin/
  23. google_apis/
  24. google_update/
  25. gpu/
  26. headless/
  27. infra/
  28. ios/
  29. ipc/
  30. media/
  31. mojo/
  32. native_client_sdk/
  33. net/
  34. pdf/
  35. ppapi/
  36. printing/
  37. remoting/
  38. rlz/
  39. sandbox/
  40. services/
  41. skia/
  42. sql/
  43. storage/
  44. styleguide/
  45. testing/
  46. third_party/
  47. tools/
  48. ui/
  49. url/
  50. weblayer/
  51. .clang-format
  52. .clang-tidy
  53. .eslintrc.js
  54. .git-blame-ignore-revs
  55. .gitattributes
  56. .gitignore
  57. .gn
  58. .mailmap
  59. .rustfmt.toml
  60. .vpython
  61. .vpython3
  62. .yapfignore
  63. AUTHORS
  64. BUILD.gn
  65. CODE_OF_CONDUCT.md
  66. codereview.settings
  67. DEPS
  68. DIR_METADATA
  69. ENG_REVIEW_OWNERS
  70. LICENSE
  71. LICENSE.chromium_os
  72. OWNERS
  73. PRESUBMIT.py
  74. PRESUBMIT_test.py
  75. PRESUBMIT_test_mocks.py
  76. README.md
  77. WATCHLISTS
README.md

Logo Chromium

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For historical reasons, there are some small top level directories. Now the guidance is that new top level directories are for product (e.g. Chrome, Android WebView, Ash). Even if these products have multiple executables, the code should be in subdirectories of the product.

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