- In log.cc, we used InstructionStart() for code create events, but
  the Code object address for code move events. Change to use
  InstructionStart() for both.
- The symbol table contains some kind of virtual address, not file
  offsets. They happened to be identical in the past but are no longer,
  probably due to toolchain changes. Now we use objdump to figure out
  the difference between virtual addresses and file offsets.
- When a new code object happened to be created at the same address as
  a previous one, we wouldn't update it.
  This is indeed wrong, as predicted in a TODO by Jaro.
- For 64bit addresses, using >>> is wrong, now replaced with division.


Change-Id: Ib23114ed736f98bfc33c65004a039a3fd04d3c49
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2016586Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66145}