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* Fix Clang-tidy modernize-use-override warnings in some files in ↵Eugene Zelenko2015-10-211-13/+15
| | | | | | | | source/Plugins; other minor fixes. Differential Revision: http://reviews.llvm.org/D13951 llvm-svn: 250925
* Improve UnwindLLDB with better detection for unwinding failuresTamas Berghammer2015-07-061-2/+10
| | | | | | | | | | | | | | | | | | | Previously we accepted a frame as correct result if the PC pointed into an executable section of code. The isse with that approac is that if we calculated PC correctly but messed up the value of CFA then unwinding from the next fram will most likely fail. With this change I modify the logic with keeping the requirement for PC to point to an executable section and also check that we can continue the unwind from the frame we calculated. If continuing from the frame calculated with the primary unwind plan isn't working then fall back to the fallback plan with the hope for a better frame (if the fallback plan won't help then we acceot the frame from the primary plan). Differential revision: http://reviews.llvm.org/D10932 llvm-svn: 241434
* Add a new 'eRegisterInLiveRegisterContext' RegisterLocation to trackJason Molenda2014-12-091-1/+2
| | | | | | | | | | | | | | a register value that is live in the stack frame 0 register context. Fixes a problem where retrieving a register value on stack frame #n would involved O(n!) stack frame checks. This could be very slow on a deep stack when retrieving register values that had not been modified/saved by any of the stack frames. Not common, but annoying when it was hit. <rdar://problem/19010211> llvm-svn: 223843
* Add a new target setting, trap-handler-names, where a user canJason Molenda2014-02-141-0/+20
| | | | | | | | | | | | specify a list of functions which should be treated as trap handlers. This will be primarily useful to people working in non-user-level process debugging - kernels and other standalone environments. For most people, the trap handler functions provided by the Platform plugin will be sufficient. <rdar://problem/15835846>, <rdar://problem/15982682> llvm-svn: 201386
* Roll back the changes I made in r193907 which created a new FrameJason Molenda2013-11-041-1/+1
| | | | | | | | | | pure virtual base class and made StackFrame a subclass of that. As I started to build on top of that arrangement today, I found that it wasn't working out like I intended. Instead I'll try sticking with the single StackFrame class -- there's too much code duplication to make a more complicated class hierarchy sensible I think. llvm-svn: 193983
* Add a new base class, Frame. It is a pure virtual function whichJason Molenda2013-11-021-1/+1
| | | | | | | | | | | | | | | | | | | | | defines a protocol that all subclasses will implement. StackFrame is currently the only subclass and the methods that Frame vends are nearly identical to StackFrame's old methods. Update all callers to use Frame*/Frame& instead of pointers to StackFrames. This is almost entirely a mechanical change that touches a lot of the code base so I'm committing it alone. No new functionality is added with this patch, no new subclasses of Frame exist yet. I'll probably need to tweak some of the separation, possibly moving some of StackFrame's methods up in to Frame, but this is a good starting point. <rdar://problem/15314068> llvm-svn: 193907
* Change UnwindLLDB::SearchForSavedLocationForRegister so that it will allow forJason Molenda2013-06-051-1/+1
| | | | | | | | | | the link register save location being in the link register - in which case we should iterate down the stack, not recursively try to find the lr in the current frame over and over. <rdar://problem/13932954> llvm-svn: 183282
* After discussing with Chris Lattner, we require C++11, so lets get rid of ↵Greg Clayton2013-04-181-2/+2
| | | | | | the macros and just use C++11. llvm-svn: 179805
* A change in how we search for saved register values unintentionallyJason Molenda2012-11-161-0/+7
| | | | | | | | | allowed volatile registers to be returned up the stack. That leads to unexpected/incorrect values provided to the user and we need to avoid that. <rdar://problem/12714247> llvm-svn: 168123
* Add a new capability to RegisterContextLLDB: To recognize when theJason Molenda2012-10-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | Full UnwindPlan is trying to do an impossible unwind; in that case invalidate the Full UnwindPlan and replace it with the architecture default unwind plan. This is a scenario that happens occasionally with arm unwinds in particular; the instruction analysis based full unwindplan can mis-parse the functions and the stack walk stops prematurely. Now we can do a simpleminded frame-chain walk to find the caller frame and continue the unwind. It's not ideal but given the complicated nature of analyzing the arm functions, and the lack of eh_frame information on iOS, it is a distinct improvement and fixes some long-standing problems with the unwinder on that platform. This is fixing <rdar://problem/12091421>. I may re-use this invalidate feature in the future if I can identify other cases where the full unwindplan's unwind information is clearly incorrect. This checkin also includes some cleanup for the volatile register definition in the arm ABI plugin for <rdar://problem/10652166> although work remains to be done for that bug. llvm-svn: 166757
* <rdar://problem/10434005>Greg Clayton2012-03-141-2/+2
| | | | | | | Prepare LLDB to be built with C++11 by hiding all accesses to std::tr1 behind macros that allows us to easily compile for either C++. llvm-svn: 152698
* Make the StackFrameList::GetFrameAtIndex only fetch as many stack frames as ↵Jim Ingham2012-02-291-0/+5
| | | | | | | | | needed to get the frame requested. <rdar://problem/10943135> llvm-svn: 151705
* Switching back to using std::tr1::shared_ptr. We originally switched awayGreg Clayton2012-01-291-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | due to RTTI worries since llvm and clang don't use RTTI, but I was able to switch back with no issues as far as I can tell. Once the RTTI issue wasn't an issue, we were looking for a way to properly track weak pointers to objects to solve some of the threading issues we have been running into which naturally led us back to std::tr1::weak_ptr. We also wanted the ability to make a shared pointer from just a pointer, which is also easily solved using the std::tr1::enable_shared_from_this class. The main reason for this move back is so we can start properly having weak references to objects. Currently a lldb_private::Thread class has a refrence to its parent lldb_private::Process. This doesn't work well when we now hand out a SBThread object that contains a shared pointer to a lldb_private::Thread as this SBThread can be held onto by external clients and if they end up using one of these objects we can easily crash. So the next task is to start adopting std::tr1::weak_ptr where ever it makes sense which we can do with lldb_private::Debugger, lldb_private::Target, lldb_private::Process, lldb_private::Thread, lldb_private::StackFrame, and many more objects now that they are no longer using intrusive ref counted pointer objects (you can't do std::tr1::weak_ptr functionality with intrusive pointers). llvm-svn: 149207
* Restructure the relationship between UnwindLLDB and theJason Molenda2011-11-011-4/+39
| | | | | | | | | | | | | | | | | | RegisterContextLLDBs it contains. Previously RegisterContextLLDB objects had a pointer to their "next" frame down the stack. e.g. stack starts at frame 0; frame 3 has a pointer to frame 2. This is used to retreive callee saved register values. When debugging an inferior that has blown out its own stack, however, this could result in lldb blowing out its own stack while recursing down to retrieve register values. RegisterContextLLDB no longer has a pointer to its next frame; it has a reference to the UnwindLLDB which contains it. When it needs to retrieve a reg value, it asks the UnwindLLDB for that reg value and UnwindLLDB iterates through the frames until it finds a location. llvm-svn: 143423
* Lock the Unwinder before accessing it.Jim Ingham2011-10-211-4/+5
| | | | llvm-svn: 142632
* ABI plug-ins must implement the following pure virtual functions:Greg Clayton2011-05-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | virtual bool ABI::StackUsesFrames () = 0; Should return true if your ABI uses frames when doing stack backtraces. This means a frame pointer is used that points to the previous stack frame in some way or another. virtual bool ABI::CallFrameAddressIsValid (lldb::addr_t cfa) = 0; Should take a look at a call frame address (CFA) which is just the stack pointer value upon entry to a function. ABIs usually impose alignment restrictions (4, 8 or 16 byte aligned), and zero is usually not allowed. This function should return true if "cfa" is valid call frame address for the ABI, and false otherwise. This is used by the generic stack frame unwinding code to help determine when a stack ends. virtual bool ABI::CodeAddressIsValid (lldb::addr_t pc) = 0; Validates a possible PC value and returns true if an opcode can be at "pc". Some ABIs or architectures have fixed width instructions and must be aligned to a 2 or 4 byte boundary. "pc" can be an opcode or a callable address which means the load address might be decorated with extra bits (such as bit zero to indicate a thumb function call for ARM targets), so take this into account when returning true or false. The address should also be validated to ensure it is a valid address for the address size of the inferior process. 32 bit targets should make sure the address is less than UINT32_MAX. Modified UnwindLLDB to use the new ABI functions to help it properly terminate stacks. Modified the mach-o function that extracts dependent files to not resolve the path as the paths inside a binary might not match those on the current host system. llvm-svn: 132021
* Fixed the LLDB build so that we can have private types, private enums andGreg Clayton2011-03-241-1/+1
| | | | | | | | public types and public enums. This was done to keep the SWIG stuff from parsing all sorts of enums and types that weren't needed, and allows us to abstract our API better. llvm-svn: 128239
* All UnwindPlan objects are now passed around as shared pointers.Greg Clayton2011-02-151-6/+6
| | | | | | | | | | | | | ArchDefaultUnwindPlan plug-in interfaces are now cached per architecture instead of being leaked for every frame. Split the ArchDefaultUnwindPlan_x86 into ArchDefaultUnwindPlan_x86_64 and ArchDefaultUnwindPlan_i386 interfaces. There were sporadic crashes that were due to something leaking or being destroyed when doing stack crawls. This patch should clear up these issues. llvm-svn: 125541
* Added memory caching to lldb_private::Process. All lldb_private::ProcessGreg Clayton2011-01-071-1/+1
| | | | | | | | | | | | | | | | | | subclasses will automatically be able to take advantage of caching. The cache line size is set to 512 by default. This greatly speeds up stack backtraces on MacOSX when using the ProcessGDBRemote process plug-in since only about 6300 packets per second can be sent. Initial speedups show: Prior to caching: 10,000 stack frames took 5.2 seconds After caching: 10,000 stack frames in 240 ms! About a 20x speedup! llvm-svn: 122996
* Fixed issues with RegisterContext classes and the subclasses. There wasGreg Clayton2011-01-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | an issue with the way the UnwindLLDB was handing out RegisterContexts: it was making shared pointers to register contexts and then handing out just the pointers (which would get put into shared pointers in the thread and stack frame classes) and cause double free issues. MallocScribble helped to find these issues after I did some other cleanup. To help avoid any RegisterContext issue in the future, all code that deals with them now returns shared pointers to the register contexts so we don't end up with multiple deletions. Also now that the RegisterContext class doesn't require a stack frame, we patched a memory leak where a StackFrame object was being created and leaked. Made the RegisterContext class not have a pointer to a StackFrame object as one register context class can be used for N inlined stack frames so there is not a 1 - 1 mapping. Updates the ExecutionContextScope part of the RegisterContext class to never return a stack frame to indicate this when it is asked to recreate the execution context. Now register contexts point to the concrete frame using a concrete frame index. Concrete frames are all of the frames that are actually formed on the stack of a thread. These concrete frames can be turned into one or more user visible frames due to inlining. Each inlined stack frame has the exact same register context (shared via shared pointers) as any parent inlined stack frames all the way up to the concrete frame itself. So now the stack frames and the register contexts should behave much better. llvm-svn: 122976
* Refactor UnwindLLDB so it doesn't populate the entire stack unlessJason Molenda2010-11-091-0/+3
| | | | | | | | | | | | | the frame count is requested or each frame is individually requested. In practice this doesn't seem to help anything because we have functions like StackFrameList::GetNumFrames() which is going to request each frame anyway. And classes like ThreadPlanStepRange and ThreadPlanStepOverRange get the stack depth in their ctor forcing a full stack walk. But at least UnwindLLDB will delay doing a full walk if it can. llvm-svn: 118477
* Fix thinko in UnwindTable.cpp where it wouldn't provde a Jason Molenda2010-11-091-0/+1
| | | | | | | | | | FuncUnwinders object if the eh_frame section was missing from an objfile. Worked fine on x86_64 but on i386 where eh_frame is unusual, that resulted in the arch default UnwindPlan being used all the time instead of picking up an assembly profile based unwindplan. llvm-svn: 118467
* Built the native unwinder with all the warnings c++-4.2 could muster;Jason Molenda2010-11-041-0/+1
| | | | | | | | | fixed them. Added DISALLOW_COPY_AND_ASSIGN to classes that should not be bitwise copied. Added default initializers for member variables that weren't being initialized in the ctor. Fixed a few shadowed local variable mistakes. llvm-svn: 118240
* Handle the case where no eh_frame section is present.Jason Molenda2010-11-041-1/+3
| | | | | | | | | | | | | RegisterContextLLDB holds a reference to the SymbolContext in the vector of Cursors that UnwindLLDB maintains. Switch UnwindLLDB to hold a vector of shared pointers of Cursors so this reference doesn't become invalid. Correctly falling back from the "fast" UnwindPlan to the "full" UnwindPlan when additional registers need to be retrieved. llvm-svn: 118218
* Check in the native lldb unwinder. Jason Molenda2010-10-251-0/+70
Not yet enabled as the default unwinder but there are no known backtrace problems with the code at this point. Added 'log enable lldb unwind' to help diagnose backtrace problems; this output needs a little refining but it's a good first step. eh_frame information is currently read unconditionally - the code is structured to allow this to be delayed until it's actually needed. There is a performance hit when you have to parse the eh_frame information for any largeish executable/library so it's necessary to avoid if possible. It's confusing having both the UnwindPlan::RegisterLocation struct and the RegisterConextLLDB::RegisterLocation struct, I need to rename one of them. The writing of registers isn't done in the RegisterConextLLDB subclass yet; neither is the running of complex DWARF expressions from eh_frame (e.g. used for _sigtramp on Mac OS X). llvm-svn: 117256
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