This abstracts read/write locks on the current host system. It is currently backed by pthread_rwlock_t objects so it should work on all unix systems.
We also need a way to control multi-threaded access to the process through the public API when it is running. For example it isn't a good idea to try and get stack frames while the process is running. To implement this, the lldb_private::Process class now contains a ReadWriteLock member variable named m_run_lock which is used to control the public process state. The public process state represents the state of the process as the client knows it. The private is used to control the actual current process state. So the public state of the process can be stopped, yet the private state can be running when evaluating an expression for example.
Adding the read/write lock where readers are clients that want the process to stay stopped, and writers are clients that run the process, allows us to accurately control multi-threaded access to the process.
Switched the SBThread and SBFrame over to us shared pointers to the ExecutionContextRef class instead of making their own class to track this. This fixed an issue with assigning on SBFrame to another and will also centralize the code that tracks weak references to execution context objects into one location.
llvm-svn: 154099
correctly if the setter/getter were not present
in the debug information. The fixes are as follows:
- We not only look for the method by its full name,
but also look for automatically-generated methods
when searching for a selector in an Objective-C
interface. This is necessary to find accessors.
- Extract the getter and setter name from the
DW_TAG_APPLE_Property declaration in the DWARF
if they are present; generate them if not.
llvm-svn: 154067
Found an issue where we might still have shared pointer references to lldb_private::Thread objects where the object itself is not valid and has been removed from the Process. When a thread is removed from a process, it will call Thread::DestroyThread() which well set a boolean member variable which is exposed now via:
bool
Thread::IsValid() const;
We then check the thread validity before handing out a shared pointer.
llvm-svn: 154048
Fixed an issue where there were more than one way to get a CompileUnitSP created when using SymbolFileDWARF with SymbolFileDWARFDebugMap. This led to an assertion that would fire under certain conditions. Now there is only one way to create the compile unit and it will "do the right thing".
llvm-svn: 153908
(lldb) log enable --verbose lldb completion
This will print out backtraces for all type completion calls which will help us verify that we don't ever complete a type when we don't need to.
llvm-svn: 153787
ValueObject, and make sure that ValueObjects that
have null type names (because they have null types)
also have null qualified type names. This avoids
some potential crashes if
ValueObject::GetQualifiedTypeName tries to get the
name of their type by calling GetClangTypeImpl().
llvm-svn: 153718
Fixed an issue that could cause circular type parsing that will assert and kill LLDB.
Prior to this fix the DWARF parser would always create class types and not start their definitions (for both C++ and ObjC classes) until we were asked to complete the class later. When we had cases like:
class A
{
class B
{
};
};
We would alway try to complete A before specifying "A" as the decl context for B. Turns out we can just start the definition and still not complete the class since we can check the TagDecl::isCompleteDefinition() function. This only works for C++ types. This means we will not be pulling in the full definition of parent classes all the time and should help with our memory consumption and also reduce the amount of debug info we have to parse.
I also reduced redundant code that was checking in a lldb::clang_type_t was a possible C++ dynamic type since it was still completing the type, just to see if it was dynamic. This was fixed in another function that was checking for a type being dynamic as an ObjC or a C++ type, but there was dedicated fucntion for C++ that we missed.
llvm-svn: 153713
Symbol files (dSYM files on darwin) can now be specified during program execution:
(lldb) target symbols add /path/to/symfile/a.out.dSYM/Contents/Resources/DWARF/a.out
This command can be used when you have a debug session in progress and want to add symbols to get better debug info fidelity.
llvm-svn: 153693
Line tables when using DWARF in .o files can be wrong when two entries get moved around by the compiler. This was due to incorrect logic in the line entry comparison operator.
llvm-svn: 153685
We are introducing a new Logger class on the Python side. This has the same purpose, but is unrelated, to the C++ logging facility
The Pythonic logging can be enabled by using the following scripting commands:
(lldb) script Logger._lldb_formatters_debug_level = {0,1,2,...}
0 = no logging
1 = do log
2 = flush after logging each line - slower but safer
3 or more = each time a Logger is constructed, log the function that has created it
more log levels may be added, each one being more log-active than the previous
by default, the log output will come out on your screen, to direct it to a file:
(lldb) script Logger._lldb_formatters_debug_filename = 'filename'
that will make the output go to the file - set to None to disable the file output and get screen logging back
Logging has been enabled for the C++ STL formatters and for Cocoa class NSData - more logging will follow
synthetic children providers for classes list and map (both libstdcpp and libcxx) now have internal capping for safety reasons
this will fix crashers where a malformed list or map would not ever meet our termination conditions
to set the cap to a different value:
(lldb) script {gnu_libstdcpp|libcxx}.{map|list}_capping_size = new_cap (by default, it is 255)
you can optionally disable the loop detection algorithm for lists
(lldb) script {gnu_libstdcpp|libcxx}.list_uses_loop_detector = False
llvm-svn: 153676
for unbacked properties. We support two variants:
one in which the getter/setter are provided by
selector ("mySetter:") and one in which the
getter/setter are provided by signature
("-[MyClass mySetter:]").
llvm-svn: 153675
<rdar://problem/11051056>
Found a race condition when sending async packets in the ProcessGDBRemote.
A little background: GDB remote clients can only send one packet at a time. You must send a packet and wait for a response. So when we continue, we obviously can't hold up the calling thread waiting for the process to stop again, so we have an async thread in the ProcessGDBRemote whose only job is to run packets that control the inferior process. When you send a continue packet, the only packet you can send is an interrupt packet (which consists of sending a CTRL+C (or a '\x03' byte)). This then stops the inferior and we can send the async packet, and then resume the target. There was a race condition that often happened during stepping where we are doing a source level single step which consists of many instruction steps and a few runs here and there when we step into a function. So the flow looks like:
inst single step
inst single step
inst single step
inst single step
inst single step
step BP and run
inst single step
inst single step
inst single step
Now if we got an async packet while the program is running we get something like:
send --> continue
send --> interrupt
recv <-- interrupt stop reply packet
send --> async packet
recv <-- async response
send --> continue again and wait for actual stop
Problems arise when this was happening when single stepping a thread where we would get:
send --> step thread 123
send --> interrupt
send --> stop reply for thread 123 (from the step)
Now we _might_ have an extra stop reply packet from the "interrupt" which we weren't checking for and we could end up with:
send --> async packet (like memory read!)
recv <-- async response (which is the interrupt stop reply packet)
Now we have the read memroy reply sitting in our buffer and waiting to be used as the reply for the next packet...
To further complicate things, the single step should have exited the async thread since the run control is finished, but now it will continue if it was interrupted.
The fixes I checked in to two major things:
- watch for the extra stop reply if we need to
- make sure we exit from the async thread run loop when the previous run control (like the instruction level single step) is finished.
Needless to say this makes very fast stepping in Xcode much more reliable.
llvm-svn: 153629
Fixed an issue with stepping where the stack frame list could get changed out from underneath you when multiple threads start accessing frame info.
llvm-svn: 153627
Bill Wendling