Summary:
Building on the infra in the previous commits, "fix" all the call sites
that introduce invalidations to make sure they also update the
corresponding histories. This is only possible to do when the access
leading to the invalidation can be recorded. Right now the only place
that's untraceable is the model of `free`/`delete`, because it happens
to be the only place where we invalidate an address without knowing
where it comes from (`free(v)`: what was v's access path? we could track
this in the future).
Reviewed By: skcho
Differential Revision: D28118764
fbshipit-source-id: de67f449e
Summary:
The eventual goal is to stop having separate sections of the trace
("invalidation part" + "access part") when the "access part" already
goes through the invalidation step. For this, it needs to record when a
value is made invalid along the path.
This is also important for assignements to NULL/0/nullptr/nil: right now
the way we record that 0 is not a valid address is via an attribute
attached to the abstract value that corresponds to 0. This makes traces
inconsistent sometimes: 0 can appear in many places in the same function
and we won't necessarily pick the correct one. In other words, attaching
traces to *values* is fragile, as the same value can be produced in many
ways. On the other hand, histories are stored at the point of access, eg
x->f, so have a much better chance of being correct. See added test:
right now its traces is completely wrong and makes the 0 in `if
(utf16StringLen == 0)` the source of the NULL value instead of the
return of `malloc()`!
This diff makes the traces slightly more verbose for now but this is
fixed in a following diff as the traces that got longer are those that
don't actually need an "invalidation" trace.
Reviewed By: skcho
Differential Revision: D28098337
fbshipit-source-id: e17929259
markma
Jules Villard