to be fed 4 callbacks: read/write memory, and read/write registers. After this,
you can tell the object to read an instruction. This will cause the class to read
the PC, and read and instruction. Then you can emulate the instruction by calling
EvaluateInstruction. This will cause the class to figure out exactly what an opcode
does, and call the read/write mem/regs functions with actual values which allows one
to emulate an instruction without running a process, or it allows one to watch the
context information (the memory write is a pushing register 3 onto the stack at offset
12) so it can be used for generating call frame information. This way, in the future,
we will have one class that can be used to emulate instructions and generate our
unwind info from assembly.
llvm-svn: 123998
bool RegisterContextLLDB::GetPC (addr_t& pc);
to:
bool RegisterContextLLDB::ReadPC (addr_t& pc);
To avoid confusion with the GetPC() function that is part of the
lldb_private::RegisterContext:
uint64_t RegisterContext::GetPC (uint64_t fail_value);
Bad things could happen if the two got intermixed and the wrong one got
called.
Fixed inifinite loop detection by watching for two frames where the
RegisterContextLLDB::CursorSP contains the same start_pc and cfa.
llvm-svn: 123673
a method:
void RegisterContext::InvalidateIfNeeded (bool force);
Each time this function is called, when "force" is false, it will only call
the pure virtual "virtual void RegisterContext::InvalideAllRegisters()" if
the register context's stop ID doesn't match that of the process. When the
stop ID doesn't match, or "force" is true, the base class will clear its
cached registers and the RegisterContext will update its stop ID to match
that of the process. This helps make it easier to correctly flush the register
context (possibly from multiple locations depending on when and where new
registers are availabe) without inadvertently clearing the register cache
when it doesn't need to be.
Modified the ProcessGDBRemote plug-in to be much more efficient when it comes
to:
- caching the expedited registers in the stop reply packets (we were ignoring
these before and it was causing us to read at least three registers every
time we stopped that were already supplied in the stop reply packet).
- When a thread has no stop reason, don't keep asking for the thread stopped
info. Prior to this fix we would continually send a qThreadStopInfo packet
over and over when any thread stop info was requested. We now note the stop
ID that the stop info was requested for and avoid multiple requests.
Cleaned up some of the expression code to not look for ClangExpressionVariable
objects up by name since they are now shared pointers and we can just look for
the exact pointer match and avoid possible errors.
Fixed an bug in the ValueObject code that would cause children to not be
displayed.
llvm-svn: 123127
frames, UnwindLLDB could create the incorrect RegisterContext for a given
stack frame because it was using the frame index (not the concrete frame
index). This was causing crashes when doing backtraces through the
SBFrame::GetFP() because a NULL register context was being returned for the
deepest stack frame.
llvm-svn: 123052
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
cache even when a valid process exists. Previously, Target::ReadMemory would
read from the process if there was a valid one and then fallback to the
object file cache.
llvm-svn: 122989
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
0 mid-stack, stop backtracing.
SectionLoadList.cpp (ResolveLoadAddress): Don't assert on an
out-of-range address, just return an invalid Address object.
The unwinder may be passing in invalid addresses on the final
stack frame and the assert is a problem.
llvm-svn: 122386
RegisterContext* - normally this is retrieved from the ExecutionContext's
StackFrame but when we need to evaluate an expression while creating
the stack frame list this can be a little tricky.
Add DW_OP_deref_size, needed for the _sigtramp FDE expression.
Add support for processing DWARF expressions in RegisterContextLLDB.
Update callers to DWARFExpression::Evaluate.
llvm-svn: 119885