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
minor changes to make stack unwinding on amd64-linux approximately
twice as fast as it was before.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@8707
support to Memcheck for tracking the origin of uninitialised values,
if you use the --track-origins=yes flag.
This currently causes some Memcheck regression tests to fail, because
they now print an extra line of advisory text in their output. This
will be fixed.
The core-tool interface is slightly changed. The version number for
the interface needs to be incremented.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@7982
of VG_(record_ExeContext), which just records the first stack frame
but does not attempt to unwind the (guest) stack. This is useful in
situations where we suspect unwinding the stack might cause a
segfault.
Use this in m_signals, when getting a backtrace following a guest
segfault.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@7304
kludges^H^H^H^H^H^H^Henhancements:
r6802: For VG_(record_ExeContext) et al, add a new parameter
(first_ip_delta) which is added to the initial IP value before the
stack is unwound. A safe value to pass is zero, which causes the
existing behaviour to be unchanged. This is a kludge needed to work
around the incomplete amd64 stack unwind info in glibc-2.5's clone()
routine.
r7059: Add a last-ditch heuristic-hack to the amd64-linux stack
unwinder, which is used when all other methods fail. Seems like GDB
has something similar.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@7118
two halves: stacktrace.c, which deals with getting, traversing and printing
stack traces; and execontext.c, which deals with storing stack traces
permanently in a way that avoids duplicates, and comparing them.
One nice outcome: previously we were often creating ExeContexts, which live
forever, even when they were only needed temporarily. Ie. this was a memory
leak, which has been removed.
As part of this, new headers have been created, carved off core.h and
tool.h. Lots of function names have changed, too.
In Massif, I also changed a lot of "eip" names to "ip" to make them less
x86-specific.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@3429
