tree b07bfa303945cb1f2f1694ba5dc106efdb0ab836
parent 0ed3fb3deecc85ba8e373d58184d0c05457885b4
author Vyacheslav Egorov <vegorov@google.com> 1613922507 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> 1613922507 +0000

[vm] Fix vm_snapshot_analysis logic and tests

* When looking for Code node owner simply always check for synthetic
  owner (referenced through ':owner_' property) first. If it is present
  then it means 'owner_' property is invalid anyway. 25fd0200ef1 changed
  how WSRs are written into snapshot (instead of writing WSRs we are
  simply writing SMI CIDs) which broke previous logic.
* When building ProgramInfoNode for a Class node accommodate for the
  existence of classes which don't have 'library_' property (e.g. base
  objects like void and dynamic). Additionally, adjust how these base
  objects are written into the snapshot profile so that we preserve
  their names.
* Tweak tests diff and diff-collapse tests to pass, they were failing
  because prologue removal compiler change made some of the diffs so
  tiny that they are ignored by threshold filtering.
* Add two more tests: one that verifies that tracings flags don't have
  any impact on the snapshot size and one that checks we correct
  attribute instructions size to the function node from which these
  instructions originated. This last test is added in anticipation of
  Code object removal to make sure that vm_snapshot_analysis continues
  to work correctly.
* Adjust sorting rules for Code cluster to make it more stable between
  slightly different programs to stabilize output of
  --print-instructions-sizes-to (depends on the sorting algorithm used
  in libc, the test was failing on Mac but not on Linux).

These fixes should unblock relanding of b6dc4dad4da

Fixes #44507
Fixes flutter/flutter#76313

TEST=pkg/vm_snapshot_analysis/test/instruction_sizes_test.dart

Cq-Include-Trybots: luci.dart.try:pkg-linux-release-try,pkg-win-release-try,pkg-mac-release-try
Change-Id: Iee0221dd3a507cb4f36d530404693ebfab3b7bf2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/185826
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>