commit 703bcab9106cd475d024e3c89825d43129db8e56
author Ryan Savitski <rsavitski@google.com> Wed Dec 18 14:38:14 2019 +0000
committer Ryan Savitski <rsavitski@google.com> Wed Dec 18 14:38:14 2019 +0000
tree 0459b50d54d28bd365aad14350112e304b21fbeb
parent 3be20911d9a33f9fefc0a4d283345407c86e3c1c

traced_perf: in-tree builds: arm register parsing basics

This adds libunwindstack as a dependency for traced_perf, and has the necessary
logic to sample the userspace register state of sampled processes. The
registers are converted to libunwindstack's representation and, for now,
printed.

Only supporting arm32/arm64 at the moment. x86 coming soon, standalone builds
require figuring out where to source the uapi constant definitions from.

Sorry, no tests at this point, more of a "I've ran this and it printed
something sensible according to /proc/pid/maps".

Also changes traced_perf to only build in the Android tree atm.

Change-Id: Id0df3b8c3901d733480d4289cf9b37562c3427d8