symbols correctly. There were a couple of pieces to this.
1) When a breakpoint location finds itself pointing to an Indirect symbol, when the site for it is created
it needs to resolve the symbol and actually set the site at its target.
2) Not all breakpoints want to do this (i.e. a straight address breakpoint should always set itself on the
specified address, so somem machinery was needed to specify that.
3) I added some info to the break list output for indirect symbols so you could see what was happening.
Also I made it clear when we re-route through re-exported symbols.
4) I moved ResolveIndirectFunction from ProcessPosix to Process since it works the exact same way on Mac OS X
and the other posix systems. If we find a platform that doesn't do it this way, they can override the
call in Process.
5) Fixed one bug in RunThreadPlan, if you were trying to run a thread plan after a "running" event had
been broadcast, the event coalescing would cause you to miss the ThreadPlan running event. So I added
a way to override the coalescing.
6) Made DynamicLoaderMacOSXDYLD::GetStepThroughTrampolinePlan handle Indirect & Re-exported symbols.
<rdar://problem/15280639>
llvm-svn: 198976
The former will set the Address object's offset to the load address value if
it is not present in any section; the latter will only set the Address object
if the load addr is contained in one of its sections.
<rdar://problem/15135987>
llvm-svn: 198469
its stack frame is a constructed, fake thing that may not conform
correctly to these rules. This fixes a problem where lldb couldn't
backtrace past an asynchronous signal handler (_sigtramp) frame on
a stack on Mac OS X.
<rdar://problem/15035673>
llvm-svn: 198450
The original code was not completely correct, but a form of
this check is necessary to avoid an infinite recursion on
some unwind cases where a function unwinds to itself with the
same CFA. Ashok thought the recursion would be caught in
RegisterContextLLDB but this one isn't - we still need it here.
<rdar://problem/15664282>
llvm-svn: 197761
In those set of patches, Ashok changed Module::ResolveSymbolContextForAddress
so that if it failed to find a symbol for a pc, it could back up
the pc value by 1 and re-search for a symbol.
His change to RegisterContextLLDB.cpp partially duplicates that
behavior but it also removes the separate case where we find a
Symbol for the pc address but it's the wrong symbol -- we need to
handle this as well as the lookup-by-pc-finds-no-symbol case.
The most obvious fallout from this regression was that lldb on
Mac OS X couldn't backtrace past __assert_rtn() which tail-calls
abort(). e.g.
(lldb) bt
* thread #1: tid = 0x5d6ea1, 0x00007fff8ee80866 libsystem_kernel.dylib`__pthread_kill + 10, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
* frame #0: 0x00007fff8ee80866 libsystem_kernel.dylib`__pthread_kill + 10
frame #1: 0x00007fff8eb5835c libsystem_pthread.dylib`pthread_kill + 92
frame #2: 0x00007fff8852ab1a libsystem_c.dylib`abort + 125
frame #3: 0x00007fff884f49bf libsystem_c.dylib`__assert_rtn + 321
frame #4: 0x0000000100000f2c a.out`main + 124
(lldb) dis -c 3 -s 0x7fff884f49b3
libsystem_c.dylib`__assert_rtn + 309:
0x7fff884f49b3: movq %rax, -0x11b96242(%rip) ; gCRAnnotations + 8
0x7fff884f49ba: callq 0x7fff8854fd2c ; symbol stub for: abort
libsystem_c.dylib`basename:
0x7fff884f49bf: pushq %rbp
(lldb)
in this case, __assert_rtn() is immediately followed by basename() and
the changes in r190812 didn't back up the pc value to get the correct
function name / unwind info.
<rdar://problem/15367233>
llvm-svn: 197655
<rdar://problem/15314403>
This patch adds a new lldb_private::SectionLoadHistory class that tracks what shared libraries were loaded given a process stop ID. This allows us to keep a history of the sections that were loaded for a time T. Many items in history objects will rely upon the process stop ID in the future.
llvm-svn: 196557
(and same thing to Thread base class) which can be used when looking
at an ExtendedBacktrace thread; it will try to find the IndexID() of
the original thread that was executing this backtrace when it was
recorded. If lldb can't find a record of that thread, it will return
the same value as IndexID() for the ExtendedBacktrace thread.
llvm-svn: 194912
do anything right now. Add a few new methods to the Thread base
class which HistoryThread needs. I think I updated all the
CMakeLists files correctly for the new plugin.
llvm-svn: 194756
Still working out some of the details of these classes but
I wanted to get the overall structure checked in.
<rdar://problem/15314068>
llvm-svn: 194245
llvm::ArrayRef of arguments rather than taking
a fixed number of possibly-NULL pointers to
arguments.
Also changed ClangFunction::GetThreadPlanToCallFunction
to take the address of the argument struct by value
instead of by reference, since it doesn't actually
modify the value passed into it.
llvm-svn: 194232
It completes the job of using EvaluateExpressionOptions consistently throughout
the inferior function calling mechanism in lldb begun in Greg's patch r194009.
It removes a handful of alternate calls into the ClangUserExpression/ClangFunction/ThreadPlanCallFunction which
were there for convenience. Using the EvaluateExpressionOptions removes the need for them.
Using that it gets the --debug option from Greg's patch to work cleanly.
It also adds another EvaluateExpressionOption to not trap exceptions when running expressions. You shouldn't
use this option unless you KNOW your expression can't throw beyond itself. This is:
<rdar://problem/15374885>
At present this is only available through the SB API's or python.
It fixes a bug where function calls would unset the ObjC & C++ exception breakpoints without checking whether
they were set by somebody else already.
llvm-svn: 194182
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
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
To make this work this patch extends LLDB to:
- Explicitly track the link_map address for each module. This is effectively the module handle, not sure why it wasn't already being stored off anywhere. As an extension later, it would be nice if someone were to add support for printing this as part of the modules list.
- Allow reading the per-thread data pointer via ptrace. I have added support for Linux here. I'll be happy to add support for FreeBSD once this is reviewed. OS X does not appear to have __thread variables, so maybe we don't need it there. Windows support should eventually be workable along the same lines.
- Make DWARF expressions track which module they originated from.
- Add support for the DW_OP_GNU_push_tls_address DWARF opcode, as generated by gcc and recent versions of clang. Earlier versions of clang (such as 3.2, which is default on Ubuntu right now) do not generate TLS debug info correctly so can not be supported here.
- Understand the format of the pthread DTV block. This is where it gets tricky. We have three basic options here:
1) Call "dlinfo" or "__tls_get_addr" on the inferior and ask it directly. However this won't work on core dumps, and generally speaking it's not a good idea for the debugger to call functions itself, as it has the potential to not work depending on the state of the target.
2) Use libthread_db. This is what GDB does. However this option requires having a version of libthread_db on the host cross-compiled for each potential target. This places a large burden on the user, and would make it very hard to cross-debug from Windows to Linux, for example. Trying to build a library intended exclusively for one OS on a different one is not pleasant. GDB sidesteps the problem and asks the user to figure it out.
3) Parse the DTV structure ourselves. On initial inspection this seems to be a bad option, as the DTV structure (the format used by the runtime to manage TLS data) is not in fact a kernel data structure, it is implemented entirely in useerland in libc. Therefore the layout of it's fields are version and OS dependent, and are not standardized.
However, it turns out not to be such a problem. All OSes use basically the same algorithm (a per-module lookup table) as detailed in Ulrich Drepper's TLS ELF ABI document, so we can easily write code to decode it ourselves. The only question therefore is the exact field layouts required. Happily, the implementors of libpthread expose the structure of the DTV via metadata exported as symbols from the .so itself, designed exactly for this kind of thing. So this patch simply reads that metadata in, and re-implements libthread_db's algorithm itself. We thereby get cross-platform TLS lookup without either requiring third-party libraries, while still being independent of the version of libpthread being used.
Test case included.
llvm-svn: 192922
- Made the dynamic register context for the GDB remote plug-in inherit from the generic DynamicRegisterInfo to avoid code duplication
- Finished up the target definition python setting stuff.
- Added a new "slice" key/value pair that can specify that a register is part of another register:
{ 'name':'eax', 'set':0, 'bitsize':32, 'encoding':eEncodingUint, 'format':eFormatHex, 'slice': 'rax[31:0]' },
- Added a new "composite" key/value pair that can specify that a register is made up of two or more registers:
{ 'name':'d0', 'set':0, 'bitsize':64 , 'encoding':eEncodingIEEE754, 'format':eFormatFloat, 'composite': ['s1', 's0'] },
- Added a new "invalidate-regs" key/value pair for when a register is modified, it can invalidate other registers:
{ 'name':'cpsr', 'set':0, 'bitsize':32 , 'encoding':eEncodingUint, 'format':eFormatHex, 'invalidate-regs': ['r8', 'r9', 'r10', 'r11', 'r12', 'r13', 'r14', 'r15']},
This now completes the feature that allows a GDB remote target to completely describe itself.
llvm-svn: 192858
When debugging with the GDB remote in LLDB, LLDB uses special packets to discover the
registers on the remote server. When those packets aren't supported, LLDB doesn't
know what the registers look like. This checkin implements a setting that can be used
to specify a python file that contains the registers definitions. The setting is:
(lldb) settings set plugin.process.gdb-remote.target-definition-file /path/to/module.py
Inside module there should be a function:
def get_dynamic_setting(target, setting_name):
This dynamic setting function is handed the "target" which is a SBTarget, and the
"setting_name", which is the name of the dynamic setting to retrieve. For the GDB
remote target definition the setting name is 'gdb-server-target-definition'. The
return value is a dictionary that follows the same format as the OperatingSystem
plugins follow. I have checked in an example file that implements the x86_64 GDB
register set for people to see:
examples/python/x86_64_target_definition.py
This allows LLDB to debug to any archticture that is support and allows users to
define the registers contexts when the discovery packets (qRegisterInfo, qHostInfo)
are not supported by the remote GDB server.
A few benefits of doing this in Python:
1 - The dynamic register context was already supported in the OperatingSystem plug-in
2 - Register contexts can use all of the LLDB enumerations and definitions for things
like lldb::Format, lldb::Encoding, generic register numbers, invalid registers
numbers, etc.
3 - The code that generates the register context can use the program to calculate the
register context contents (like offsets, register numbers, and more)
4 - True dynamic detection could be used where variables and types could be read from
the target program itself in order to determine which registers are available since
the target is passed into the python function.
This is designed to be used instead of XML since it is more dynamic and code flow and
functions can be used to make the dictionary.
llvm-svn: 192646
- Removes the block in UnwindLLDB::AddOneMoreFrame that tests for a bad stack setup,
since it is neither correct (tests the FP GPR), complete (doesn't consider multi-frame
cycles), nor reachable (the construction of RegisterContextLLDB will fail in the case
where either of the two (why just two?) previous frames have the same canonical frame
address as the frame that we propose adding to the stack).
llvm-svn: 191430
to build out the symbol table as addresses are used, and implements
the mechanism for ELF to add stripped symbols from eh_frame.
Uses this mechanism to allow disassembly for addresses corresponding
to stripped symbols for ELF, and provide hooks to implement this for
PE COFF.
Also removes eSymbolContextTailCall in favor of an option for
ResolveSymbolContextForAddress for consistency with the documentation
for eSymbolContextEverything. Essentially, this is just an option for
interpreting the so_addr.
llvm-svn: 191307
default-at-first-instruction UnwindPlan if we're at the beginning of a function and
the ABI can provide us with an UnwindPlan to get out of there before falling back
to the generic architectural default UnwindPlan (which usually assumes that the stack
has already been set up.)
Update the FuncUnwinders methods to gracefully handle the case where an assembly
profiler may not be available.
Fix a bug where FuncUnwinders::GetUnwindPlanArchitectureDefaultAtFunctionEntry was
returning the wrong UnwindPlan to its caller.
llvm-svn: 191262
Specifically, allows the unwinder to handle the case where sc.function
gets resolved with a pc that is one past the address range of the function
(consistent with a tail call). However, there is no matching symbol.
Adds eSymbolContextTailCall to provide callers with control over the scope
of symbol resolution and to allow ResolveSymbolContextForAddress to handle
tail calls since this routine is common to unwind and disassembly.
llvm-svn: 191102
for the frame is one past the address range of the calling function.
- Lowers the fix from RegisterContextLLDB for use with disassembly
- Fixes one of three issues in the disassembly test in TestInferiorAssert.py
Also adds documentation that explains the resolution depths and interface.
Note: This change affects the resolution scope for eSymbolContextFunction
without impacting the performance of eSymbolContextSymbol.
Thanks to Matt Kopec for his review.
llvm-svn: 190812
RegisterContextLLDB::SavedLocationForRegister to cache the pc and
sp register numbers -- if lldb is debugging multiple Targets of
different architectures, this will be incorrect. If these were
to be cached anywhere, it would have to be up in the Target.
llvm-svn: 186651
and -fomit-frame-pointer.
- Parses eh_frame FDEs to determine the function address and size so that
the call frame parsing can continue.
Note: This code path is specific to ELF and PECOFF, because ObjectFileMachO
uses LCT_FunctionStarts to efficiently populate the symbol table.
Thanks to Jason Molenda for the review!
llvm-svn: 186585
A long time ago we start with clang types that were created by the symbol files and there were many functions in lldb_private::ClangASTContext that helped. Later we create ClangASTType which contains a clang::ASTContext and an opauque QualType, but we didn't switch over to fully using it. There were a lot of places where we would pass around a raw clang_type_t and also pass along a clang::ASTContext separately. This left room for error.
This checkin change all type code over to use ClangASTType everywhere and I cleaned up the interfaces quite a bit. Any code that was in ClangASTContext that was type related, was moved over into ClangASTType. All code that used these types was switched over to use all of the new goodness.
llvm-svn: 186130
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
namespace lldb_private {
class Thread
{
virtual lldb::StopInfoSP
GetPrivateStopReason() = 0;
};
}
To not be virtual. The lldb_private::Thread now handles the correct caching and will call a new pure virtual function:
namespace lldb_private {
class Thread
{
virtual bool
CalculateStopInfo() = 0;
}
}
This function must be overridden by thead lldb_private::Thread subclass and the only thing it needs to do is to set the Thread::StopInfo() with the current stop reason and return true, or return false if there is no stop reason. The lldb_private::Thread class will take care of calling this function only when it is required. This allows lldb_private::Thread subclasses to be a bit simpler and not all need to duplicate the cache and invalidation settings.
Also renamed:
lldb::StopInfoSP
lldb_private::Thread::GetPrivateStopReason();
To:
lldb::StopInfoSP
lldb_private::Thread::GetPrivateStopInfo();
Also cleaned up a case where the ThreadPlanStepOverBreakpoint might not re-set its breakpoint if the thread disappears (which was happening due to a bug when using the OperatingSystem plug-ins with memory threads and real threads).
llvm-svn: 181501
thread before UnwindLLDB::AddOneMoreFrame calls it quits. We have
a couple of reports of unending backtraces in the field and we
haven't been able to collect any information about what kind of
backtrace is causing this. We've found on Mac OS X that it's tricky
to get more than around 200k stack frames before a process exceeds
its stack space so we're starting with a hard limit of 300,000 frames.
<rdar://problem/13383069>
llvm-svn: 180995
<rdar://problem/13723772>
Modified the lldb_private::Thread to work much better with the OperatingSystem plug-ins. Operating system plug-ins can now return have a "core" key/value pair in each thread dictionary for the OperatingSystemPython plug-ins which allows the core threads to be contained with memory threads. It also allows these memory threads to be stepped, resumed, and controlled just as if they were the actual backing threads themselves.
A few things are introduced:
- lldb_private::Thread now has a GetProtocolID() method which returns the thread protocol ID for a given thread. The protocol ID (Thread::GetProtocolID()) is usually the same as the thread id (Thread::GetID()), but it can differ when a memory thread has its own id, but is backed by an actual API thread.
- Cleaned up the Thread::WillResume() code to do the mandatory parts in Thread::ShouldResume(), and let the thread subclasses override the Thread::WillResume() which is now just a notification.
- Cleaned up ClearStackFrames() implementations so that fewer thread subclasses needed to override them
- Changed the POSIXThread class a bit since it overrode Thread::WillResume(). It is doing the wrong thing by calling "Thread::SetResumeState()" on its own, this shouldn't be done by thread subclasses, but the current code might rely on it so I left it in with a TODO comment with an explanation.
llvm-svn: 180886
(normally undefined) as indicating a breakpoint hit, in addition
to the normal (EXC_BREAKPOINT, EXC_ARM_BREAKPOINT) pair.
<rdar://problem/13730366>
llvm-svn: 180216
Providing a dummy RegisterContext to secure against faulty Python OS plugins that do not return a valid RegisterContext
The RegisterContextDummy exports a PC with a constant 0xFFFFFFFFFFFFFFFF value
llvm-svn: 180033
Fixed the GDB remote with the python OS plug-in to not show core threads when they aren't desired and also to have the threads "to the right thing" when continuing.
llvm-svn: 179912
defines a Return Address register (e.g. lr on arm) but the RA register
hasn't been saved anywhere yet -- it is still in a live reg.
<rdar://problem/13503130>
llvm-svn: 179431