tree 0822f7561d76de2823507442a76e48ec8c2fb514
parent b8c336f3cadbdd18b0e9900a5a53b97905b3f1de
author Alexander Markov <alexmarkov@google.com> 1639148451 +0000
committer Commit Bot <commit-bot@chromium.org> 1639148451 +0000

[vm/aot/tfa] Use RTA to improve AOT compilation speed

This change introduces Rapid Type Analysis (RTA) and uses it to
calculate initial set of allocated classes for Type Flow Analysis (TFA).
As a result, TFA converges much faster and AOT compilation time
improves.

RTA is less precise than TFA, so the set of allocated classes is
larger compared to the one calculated by TFA. However, it has only
marginal effect on the size of resulting AOT snapshots.

Time of AOT compilation step 2 on a large Flutter application
118.652s -> 59.907s (-49.5% / improved by a factor of 1.98x)
Snapshot size on armv8: -0.13%

Flutter gallery snapshot size in release and release-sizeopt modes
armv7 +0.19%, armv8 +0.2%

Just in case, RTA can be disabled using --no-rta option.

TEST=ci
Issue: https://github.com/dart-lang/sdk/issues/42442
Issue: b/154155290

Change-Id: Iffbdabe7d486cad2e138f7592bffcb70474ddc34
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/222500
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>