Added dr_where_am_i() to better support client self-profiling via
sampling.  This also provides the fragment tag, by refactoring
the pcprofile code into a new helper fcache_refine_whereami().

Renamed the whereami types to better avoid name conflicts:
s/WHERE_xxx/DR_WHERE_xxx/ and s/where_am_i_t/dr_where_am_i_t/.
Exported the dr_where_am_i_t enum.

Fixed a bug where an uninitialized mcontext was passed to a
client timer callback: we only filled in the mcontext for a
DR-internal callback.

Added a test of client sampling to client.timer

Issue: #140

Added dr_where_am_i() to better support client self-profiling via
sampling.  This also provides the fragment tag, by refactoring
the pcprofile code into a new helper fcache_refine_whereami().

Renamed the whereami types to better avoid name conflicts:
s/WHERE_xxx/DR_WHERE_xxx/ and s/where_am_i_t/dr_where_am_i_t/.
Exported the dr_where_am_i_t enum.

Fixed a bug where an uninitialized mcontext was passed to a
client timer callback: we only filled in the mcontext for a
DR-internal callback.

Added a test of client sampling to client.timer

Issue: #140

Adds a new API routine dr_track_where_am_i() which enables tracking of
whereami for clean calls.  This is off by default for performance reasons,
which leads to clean calls being labeled initially DR_WHERE_FCACHE and then
refined into DR_WHERE_UNKNOWN.

Adds a query routine dr_is_tracking_where_am_i() for use in the tracer
where this tracking causes a short jump to not reach (#2147).

Cleans up a hole in whereami tracking to include shared context switch code
and do_syscall code along with other generated transition code as
DR_WHERE_CONTEXT_SWITCH.

Adds labeling of DR_WHERE_SIGNAL_HANDLER for at least the ksynch_wait on a
suspend signal; including other handler code is trickier and is left for
future work.

Issue: #140

Adds a new API routine dr_track_where_am_i() which enables tracking of
whereami for clean calls.  This is off by default for performance reasons,
which leads to clean calls being labeled initially DR_WHERE_FCACHE and then
refined into DR_WHERE_UNKNOWN.

Adds a query routine dr_is_tracking_where_am_i() for use in the tracer
where this tracking causes a short jump to not reach (#2147).

Cleans up a hole in whereami tracking to include shared context switch code
and do_syscall code along with other generated transition code as
DR_WHERE_CONTEXT_SWITCH.

Adds labeling of DR_WHERE_SIGNAL_HANDLER for at least the ksynch_wait on a
suspend signal; including other handler code is trickier and is left for
future work.

Issue: #140

The client syscall events are called out of dispatch separately from DR's
syscall handlers, so today they end up in the DR_WHERE_DISPATCH bucket.
Here we mark them as the more appropriate DR_WHERE_SYSCALL_HANDLER.

Issue: #140

The client syscall events are called out of dispatch separately from DR's
syscall handlers, so today they end up in the DR_WHERE_DISPATCH bucket.
Here we mark them as the more appropriate DR_WHERE_SYSCALL_HANDLER.

Issue: #140

Relaxes a curiosity assert triggered by 523af3b which added further use of
DR_WHERE_SYSCALL_HANDLER.

Issue: #140

Relaxes a curiosity assert triggered by 523af3b which added further use of
DR_WHERE_SYSCALL_HANDLER.

Issue: #140