commit ddeb3b111841af52e77f2744b8f360f56be291fa
author Ryan <rsavitski@google.com> Mon Apr 12 15:55:17 2021 +0100
committer Ryan <rsavitski@google.com> Mon Apr 12 15:55:17 2021 +0100
tree bf556002ed4779fd7f263c557e2cf5e1a3a344e6
parent 9f85729fdbafefa1e1caec3775c648a5f6a25c7d

tp: experimental dynamic table for callstack annotation

This patch introduces experimental_annotated_callstack, which, given a
leaf callsite id of a callstack, reconstructs the callstack, and adds
per-frame annotations. The annotations are currently Android-specific:
interp/jit/aot ART mode for managed frames, and "common-frame" for ART
implementation details.

An annotation for a given callsite should be stable, in other words,
depending only on the path from the root. Annotations are derived
directly from the frame/mapping names.

Short version:
* art/jit/aot is based directly on the mapping
* once a managed frame is seen in a callstack, all libart frames below
  it get tagged as "common-frame", except the special case where the ART
  frame is the target of a JNI trampoline (managed->native). In these
  cases, the ART frame is a native implementation of a managed library
  method. This "next frame" logic is why the annotations require
  considering more than just a single frame.

A lot of this logic could be moved into mapping/callsite tables, but I
wish to retain the flexibility for iteration for now.

The table is based on experimental_ancestor_stack_profile_callsite. One
notable difference is that the new table also returns the queried frame.

Change-Id: I53d00f384a26111183b6bf03c79c939a6c5ef844