7 Commits

Author SHA1 Message Date
Andy Gibbs
3acfe1a3d9 Fix trivial signed/unsigned comparison warnings
llvm-svn: 224932
2014-12-29 13:03:19 +00:00
Jason Molenda
19ba9fbf27 Add support for frameless function compact unwind encodings on x86_64/i386.
This completes the compact unwind support for x86 targets.  

I'm still skipping the UNWIND_X86_64_MODE_STACK_IND encodings for
x86_64 right now because clang was emitting bad data for this form
until it was fixed in r217020 circa Sep 2014.

arm64 parsing still needs to be added.

llvm-svn: 224698
2014-12-22 11:02:02 +00:00
Jason Molenda
5c45c541a2 Various unwinder work.
Most of the changes are to the FuncUnwinders class -- as we've added
more types of unwind information, the way this class was written was
making it a mess to maintain.  Instead of trying to keep one
"non-call site" unwind plan and one "call site" unwind plan, track
all the different types of unwind plans we can possibly retrieve for
each function and have the call-site/non-call-site accessor methods
retrieve those.

Add a real "fast unwind plan" for x86_64 / i386 -- when doing an
unwind through a function, this only has to read the first 4 bytes 
to tell if the function has a standard prologue sequence.  If so, 
we can use the architecture default unwind plan to backtrace 
through this function.  If we try to retrieve the save location for
other registers later on, a real unwind plan will be used.  This
one is just for doing fast backtraces.

Change the compact unwind plan importer to fill in the valid address
range it is valid for. 

Compact unwind, in theory, may have multiple entries for a single
function.  The FuncUnwinders rewrite includes the start of supporting
this correctly.  In practice compact unwind encodings are used for
the entire range of the function today -- in fact, sometimes the same
encoding is used for multiple functions that have the same unwind
rules.  But I want to handle a single function that has multiple
different compact unwind UnwindPlans eventually.

llvm-svn: 224689
2014-12-21 10:44:54 +00:00
Jason Molenda
b12a136cdd Re-enable compact unwind use on Mac platforms.
When lldb has a binary with protected section contents,
don't use the on-disk representation of that compact 
uwnind -- read it only out of live memory where it has
been decrypted.

llvm-svn: 224670
2014-12-20 03:12:51 +00:00
Jason Molenda
0f479da711 Temporarily disable CompactUnwindInfo::GetCompactUnwindInfoForFunction.
The compact unwind importer is getting the wrong unwind info for one
case that I found.  I haven't been able to fix the problem tonight 
and I don't want to leave TOT behaving incorrectly, so just ignore
compact unwind until I can get to the bottom of this.

llvm-svn: 224321
2014-12-16 06:20:30 +00:00
Zachary Turner
818a3676aa Remove use of GCC-style intrinsics, as they are non-portable.
Differential Revision: http://reviews.llvm.org/D6567

llvm-svn: 223687
2014-12-08 20:00:33 +00:00
Jason Molenda
e589e7e336 The lldb unwinder can now use the unwind information from the compact-unwind
section for x86_64 and i386 targets on Darwin systems.  Currently only the
compact unwind encoding for normal frame-using functions is supported but it
will be easy handle frameless functions when I have a bit more free time to
test it.  The LSDA and personality routines for functions are also retrieved
correctly for functions from the compact unwind section.

This new code is very fresh -- it passes the lldb testsuite and I've done
by-hand inspection of many functions and am getting correct behavior for all
of them.  There may need to be some bug fixing over the next couple weeks as
I exercise and test it further.  But I think it's fine right now so I'm
committing it.

<rdar://problem/13220837> 

llvm-svn: 223625
2014-12-08 03:09:00 +00:00