runtime: write out a batch with alignment info for traceallocfree
Currently the traceallocfree experiment is missing info in the trace for
interpeting the produced events. Most notably, the base heap address is
missing. While not technically necessary, it is useful for getting an
accurate picture of the program's memory layout, and will be useful for
future trace experiments. Since we want to emit a batch for this, we
should also emit a batch for all the alignment info that's used to
compress the addresses (IDs) produced for the alloc/free events.
This CL distinguishes the different formats of the experimental batches
(note that there's already batches containing type information in this
experiment) by putting a byte at the beginning of each experimental
batch indicating its format.
Change-Id: Ifc4e77a23458713b7d95e0dfa056a29e1629ccd7
Reviewed-on: https://go-review.googlesource.com/c/go/+/586997
Auto-Submit: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Pratt <mpratt@google.com>