the way LLDB lazily gets complete definitions for types within the debug info.
When we run across a class/struct/union definition in the DWARF, we will only
parse the full definition if we need to. This works fine for top level types
that are assigned directly to variables and arguments, but when we have a
variable with a class, lets say "A" for this example, that has a member:
"B *m_b". Initially we don't need to hunt down a definition for this class
unless we are ever asked to do something with it ("expr m_b->getDecl()" for
example). With my previous approach to lazy type completion, we would be able
to take a "A *a" and get a complete type for it, but we wouldn't be able to
then do an "a->m_b->getDecl()" unless we always expanded all types within a
class prior to handing out the type. Expanding everything is very costly and
it would be great if there were a better way.
A few months ago I worked with the llvm/clang folks to have the
ExternalASTSource class be able to complete classes if there weren't completed
yet:
class ExternalASTSource {
....
virtual void
CompleteType (clang::TagDecl *Tag);
virtual void
CompleteType (clang::ObjCInterfaceDecl *Class);
};
This was great, because we can now have the class that is producing the AST
(SymbolFileDWARF and SymbolFileDWARFDebugMap) sign up as external AST sources
and the object that creates the forward declaration types can now also
complete them anywhere within the clang type system.
This patch makes a few major changes:
- lldb_private::Module classes now own the AST context. Previously the TypeList
objects did.
- The DWARF parsers now sign up as an external AST sources so they can complete
types.
- All of the pure clang type system wrapper code we have in LLDB (ClangASTContext,
ClangASTType, and more) can now be iterating through children of any type,
and if a class/union/struct type (clang::RecordType or ObjC interface)
is found that is incomplete, we can ask the AST to get the definition.
- The SymbolFileDWARFDebugMap class now will create and use a single AST that
all child SymbolFileDWARF classes will share (much like what happens when
we have a complete linked DWARF for an executable).
We will need to modify some of the ClangUserExpression code to take more
advantage of this completion ability in the near future. Meanwhile we should
be better off now that we can be accessing any children of variables through
pointers and always be able to resolve the clang type if needed.
llvm-svn: 123613
This patch is enough to have shared objects recognized by LLDB. We can handle
position independent executables. We can handle dynamically loaded modules
brought in via dlopen.
The DYLDRendezvous class provides an interface to a structure present in the
address space of ELF-based processes. This structure provides the address of a
function which is called by the linker each time a shared object is loaded and
unloaded (thus a breakpoint at that address will let LLDB intercept such
events), a list of entries describing the currently loaded shared objects, plus
a few other things.
On Linux, processes are brought up with an auxiliary vector on the stack. One
element in this vector contains the (possibly dynamic) entry address of the
process. One does not need to walk the stack to find this information as it is
also available under /proc/<pid>/auxv. The new AuxVector class provides a
convenient read-only view of this auxiliary vector information. We use the
dynamic entry address and the address as specified in the object file to compute
the actual load address of the inferior image. This strategy works for both
normal executables and PIE's.
llvm-svn: 123592
stuff soon when we get a fix for looking up the "OBJC_IVAR_$_Class.ivar"
style symbols into IRForTarget::ResolveExternals() next week.
llvm-svn: 123507
when handling one-liner commands that contain escaped characters. In
order to deal with the new namespace/dictionary stuff, the command was
being embedded within a second string, which messed up the escaping.
This fixes the problem by handling one-liners in a different manner, so they
no longer need to be embedded within another string, and can still be
processed in the proper namespace/dictionary context.
llvm-svn: 123467
Debuggers on ELF platforms hook into the runtime linker by monitoring a special
"rendezvous" embedded in the address space of the inferior process. The exact
location of this structure is filled in by the runtime linker and can be
resolved by locating the DT_DEBUG entry in the processes .dynamic section. The
new GetImageInfoAddress() method (morally equivalent to
Process::GetImageInfoAddress) provides the mechanism to locate this information.
GetEntryPoint() simply returns the address of the start symbol in the executable
if present. It is useful to the dynamic loader plugin for ELF systems as this
is the earliest point where LLDB can break and probe the inferiors .dynamic
section and rendezvous structure. Also, this address can be used in the
computation of the virtual base address for position independent executables.
llvm-svn: 123466
Setting m_private_state_thread to an invalid value when the child thread exits
results in a race condition between calls to ThreadCancel and ThreadJoin.
llvm-svn: 123465
Instead, it should perform a textual replacement of $(CC) from "clang" to "clang++". The same is true
for "llvm-gcc" to "llvm-g++" and for "gcc" to "g++". This way, we keep the path component of the $(CC)
passed in from the user and do not end up with a mixed toolchains with different paths.
Ditto for a newly added function called cxx_linker.
llvm-svn: 123451
Anytime we had a valid python list that was trying to go from Python down into
our C++ API, it was allocating too little memory and it ended up smashing
whatever was next to the allocated memory.
Added typemap conversions for "void *, size_t" so we can get
SBProcess::ReadMemory() working. Also added a typemap for "const void *, size_t"
so we can get SBProcess::WriteMemory() to work.
Fixed an issue in the DWARF parser where we weren't correctly calculating the
DeclContext for all types and classes. We now should be a lot more accurate.
Fixes include: enums should now be setting their parent decl context correctly.
We saw a lot of examples where enums in classes were not being properly
namespace scoped. Also, classes within classes now get properly scoped.
Fixed the objective C runtime pointer checkers to let "nil" pointers through
since these are accepted by compiled code. We also now don't call "abort()"
when a pointer doesn't validate correctly since this was wreaking havoc on
the process due to the way abort() works. We now just dereference memory
which should give us an exception from which we can easily and reliably
recover.
llvm-svn: 123428
exist within the same process (one script interpreter object per debugger object). The
python script interpreter objects are all using the same global Python script interpreter;
they use separate dictionaries to keep their data separate, and mutex's to prevent any object
attempting to use the global Python interpreter when another object is already using it.
llvm-svn: 123415
by LLDB. Instead of being materialized into the input structure
passed to the expression, variables are left in place and pointers
to them are materialzied into the structure. Variables not resident
in memory (notably, registers) get temporary memory regions allocated
for them.
Persistent variables are the most complex part of this, because they
are made in various ways and there are different expectations about
their lifetime. Persistent variables now have flags indicating their
status and what the expectations for longevity are. They can be
marked as residing in target memory permanently -- this is the
default for result variables from expressions entered on the command
line and for explicitly declared persistent variables (but more on
that below). Other result variables have their memory freed.
Some major improvements resulting from this include being able to
properly take the address of variables, better and cleaner support
for functions that return references, and cleaner C++ support in
general. One problem that remains is the problem of explicitly
declared persistent variables; I have not yet implemented the code
that makes references to them into indirect references, so currently
materialization and dematerialization of these variables is broken.
llvm-svn: 123371
A race condition exists between StopReadThread and the reader thread proper.
When StopReadThread sets m_read_thread_enabled to false the reader thread can
terminate and set m_read_thread to LLDB_INVALID_HOST_THREAD on exit. Thus calls
to ThreadCancel or ThreadJoin in StopReadThread can be passed an invalid handle.
This patch removes the race by using m_read_thread_enabled as the flag thru
which the reader thread can notify the parent thread of early/abnormal
termination.
llvm-svn: 123309
SymbolFileDWARFDebugMap handles the parsing of OSO stabs which are effectively a
Mach-O specific feature and is incompatible with other object file formats.
llvm-svn: 123308
Previously we would be posting a "FAILED" message to the log channel even when
the operation succeeded.
Also, take this opportunity to add braces thus eliminating an "ambiguous else"
compiler warning.
llvm-svn: 123306
When debugging, if an expression hits a SIGABRT, it the expression ends up
completing and stopping due the the "SIGABRT". Then the next thing that runs
(another expression, or continuing the program) ends up progating the SIGABRT
and causing the parent processes to die.
We should probably think of a different solution where we suppress any signal
that resulted due to an expression, or we modifyin the UnixSignals class to
contain a row for "suppress for expression".
So the settings for SIGABRT are: suppress = true, stop = true, and
notify = true.
llvm-svn: 123157
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
new "hexname" key for the "key:value;" duple that is part of the packet. This
allows for thread names to contain special characters such as $ # : ; + -
Debugserver now detects if the thread name contains special characters and
sends the chars in hex format if needed.
llvm-svn: 123053
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
Greg Clayton