This commit subtly changes the meaning of the values obtained via the
stack unwind mechanism (the function VG_(record_ExeContext) et al),
clears up some associated kludges, and makes suppression matching work
more reliably.
Prior to this commit, a stack snapshot contained, at [0], the IP of
the relevant thread, and at all positions [1] and above, the return
addresses for the open calls.
When showing a snapshot to the user (in VG_(apply_StackTrace)), and
searching the stack for stack blocks (in VG_(get_data_description)), 1
is subtracted from positions [1] and above, so as to move these return
addresses back to the last byte of the calling instruction. This
subtraction is also done even in VG_(get_StackTrace_wrk) itself, in
order to make the stack unwinding work at all.
It turns out that suppression-vs-function-name matching requires the
same hack, and sometimes failed to match suppressions that should
match, because of this self-same problem.
So the commit changes the stack unwinder itself, so that entries [1]
and above point to the last byte of the call instruction, rather than
the return address. The associated kludges in VG_(apply_StackTrace)
and VG_(get_StackTrace_wrk) are removed, and suppression matching is
observed to work in a case where it failed before.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@8818 a5019735-40e9-0310-863c-91ae7b9d1cf9
4 files changed