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
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 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
function and also hooked up better error reporting for when things fail.
Fixed issues with trying to display children of pointers when none are
supposed to be shown (no children for function pointers, and more like this).
This was causing child value objects to be made that were correctly firing
an assertion.
llvm-svn: 121841
values or persistent expression variables. Now if an expression consists of
a value that is a child of a variable, or of a persistent variable only, we
will create a value object for it and make a ValueObjectConstResult from it to
freeze the value (for program variables only, not persistent variables) and
avoid running JITed code. For everything else we still parse up and JIT code
and run it in the inferior.
There was also a lot of clean up in the expression code. I made the
ClangExpressionVariables be stored in collections of shared pointers instead
of in collections of objects. This will help stop a lot of copy constructors on
these large objects and also cleans up the code considerably. The persistent
clang expression variables were moved over to the Target to ensure they persist
across process executions.
Added the ability for lldb_private::Target objects to evaluate expressions.
We want to evaluate expressions at the target level in case we aren't running
yet, or we have just completed running. We still want to be able to access the
persistent expression variables between runs, and also evaluate constant
expressions.
Added extra logging to the dynamic loader plug-in for MacOSX. ModuleList objects
can now dump their contents with the UUID, arch and full paths being logged with
appropriate prefix values.
Thread hardened the Communication class a bit by making the connection auto_ptr
member into a shared pointer member and then making a local copy of the shared
pointer in each method that uses it to make sure another thread can't nuke the
connection object while it is being used by another thread.
Added a new file to the lldb/test/load_unload test that causes the test a.out file
to link to the libd.dylib file all the time. This will allow us to test using
the DYLD_LIBRARY_PATH environment variable after moving libd.dylib somewhere else.
llvm-svn: 121745
cases when getting the clang type:
- need only a forward declaration
- need a clang type that can be used for layout (members and args/return types)
- need a full clang type
This allows us to partially parse the clang types and be as lazy as possible.
The first case is when we just need to declare a type and we will complete it
later. The forward declaration happens only for class/union/structs and enums.
The layout type allows us to resolve the full clang type _except_ if we have
any modifiers on a pointer or reference (both R and L value). In this case
when we are adding members or function args or return types, we only need to
know how the type will be laid out and we can defer completing the pointee
type until we later need it. The last type means we need a full definition for
the clang type.
Did some renaming of some enumerations to get rid of the old "DC" prefix (which
stands for DebugCore which is no longer around).
Modified the clang namespace support to be almost ready to be fed to the
expression parser. I made a new ClangNamespaceDecl class that can carry around
the AST and the namespace decl so we can copy it into the expression AST. I
modified the symbol vendor and symbol file plug-ins to use this new class.
llvm-svn: 118976
adding support into lldb_private::Process:
virtual uint32_t
lldb_private::Process::LoadImage (const FileSpec &image_spec,
Error &error);
virtual Error
lldb_private::Process::UnloadImage (uint32_t image_token);
There is a default implementation that should work for both linux and MacOSX.
This ability has also been exported through the SBProcess API:
uint32_t
lldb::SBProcess::LoadImage (lldb::SBFileSpec &image_spec,
lldb::SBError &error);
lldb::SBError
lldb::SBProcess::UnloadImage (uint32_t image_token);
Modified the DynamicLoader plug-in interface to require it to be able to
tell us if it is currently possible to load/unload a shared library:
virtual lldb_private::Error
DynamicLoader::CanLoadImage () = 0;
This way the dynamic loader plug-ins are allows to veto whether we can
currently load a shared library since the dynamic loader might know if it is
currenlty loading/unloading shared libraries. It might also know about the
current host system and know where to check to make sure runtime or malloc
locks are currently being held.
Modified the expression parser to have ClangUserExpression::Evaluate() be
the one that causes the dynamic checkers to be loaded instead of other code
that shouldn't have to worry about it.
llvm-svn: 118227
by type ID (the most common type of type lookup).
Changed the API logging a bit to always show the objects in the OBJECT(POINTER)
format so it will be easy to locate all instances of an object or references
to it when looking at logs.
llvm-svn: 117641
all of the calls inlined in the header file for better performance.
Fixed the summary for C string types (array of chars (with any combo if
modifiers), and pointers to chars) work in all cases.
Fixed an issue where a forward declaration to a clang type could cause itself
to resolve itself more than once if, during the resolving of the type itself
it caused something to try and resolve itself again. We now remove the clang
type from the forward declaration map in the DWARF parser when we start to
resolve it and avoid this additional call. This should stop any duplicate
members from appearing and throwing all the alignment of structs, unions and
classes.
llvm-svn: 117437
debug information and you evaluated an expression, a crash would occur as a
result of an unchecked pointer.
Added the ability to get the expression path for a ValueObject. For a rectangle
point child "x" the expression path would be something like: "rect.top_left.x".
This will allow GUI and command lines to get ahold of the expression path for
a value object without having to explicitly know about the hierarchy. This
means the ValueObject base class now has a "ValueObject *m_parent;" member.
All ValueObject subclasses now correctly track their lineage and are able
to provide value expression paths as well.
Added a new "--flat" option to the "frame variable" to allow for flat variable
output. An example of the current and new outputs:
(lldb) frame variable
argc = 1
argv = 0x00007fff5fbffe80
pt = {
x = 2
y = 3
}
rect = {
bottom_left = {
x = 1
y = 2
}
top_right = {
x = 3
y = 4
}
}
(lldb) frame variable --flat
argc = 1
argv = 0x00007fff5fbffe80
pt.x = 2
pt.y = 3
rect.bottom_left.x = 1
rect.bottom_left.y = 2
rect.top_right.x = 3
rect.top_right.y = 4
As you can see when there is a lot of hierarchy it can help flatten things out.
Also if you want to use a member in an expression, you can copy the text from
the "--flat" output and not have to piece it together manually. This can help
when you want to use parts of the STL in expressions:
(lldb) frame variable --flat
argc = 1
argv = 0x00007fff5fbffea8
hello_world._M_dataplus._M_p = 0x0000000000000000
(lldb) expr hello_world._M_dataplus._M_p[0] == '\0'
llvm-svn: 116532
bool ValueObject::GetIsConstant() const;
void ValueObject::SetIsConstant();
This will stop anything from being re-evaluated within the value object so
that constant result value objects can maintain their frozen values without
anything being updated or changed within the value object.
Made it so the ValueObjectConstResult can be constructed with an
lldb_private::Error object to allow for expression results to have errors.
Since ValueObject objects contain error objects, I changed the expression
evaluation in ClangUserExpression from
static Error
ClangUserExpression::Evaluate (ExecutionContext &exe_ctx,
const char *expr_cstr,
lldb::ValueObjectSP &result_valobj_sp);
to:
static lldb::ValueObjectSP
Evaluate (ExecutionContext &exe_ctx, const char *expr_cstr);
Even though expression parsing is borked right now (pending fixes coming from
Sean Callanan), I filled in the implementation for:
SBValue SBFrame::EvaluateExpression (const char *expr);
Modified all expression code to deal with the above changes.
llvm-svn: 115589
results. The clang opaque type for the expression result will be added to the
Target's ASTContext, and the bytes will be stored in a DataBuffer inside
the new object. The class is named: ValueObjectConstResult
Now after an expression is evaluated, we can get a ValueObjectSP back that
contains a ValueObjectConstResult object.
Relocated the value object dumping code into a static function within
the ValueObject class instead of being in the CommandObjectFrame.cpp file
which is what contained the code to dump variables ("frame variables").
llvm-svn: 115578
adding methods to C++ and objective C classes. In order to make methods, we
need the function prototype which means we need the arguments. Parsing these
could cause a circular reference that caused an assertion.
Added a new typedef for the clang opaque types which are just void pointers:
lldb::clang_type_t. This appears in lldb-types.h.
This was fixed by enabling struct, union, class, and enum types to only get
a forward declaration when we make the clang opaque qual type for these
types. When they need to actually be resolved, lldb_private::Type will call
a new function in the SymbolFile protocol to resolve a clang type when it is
not fully defined (clang::TagDecl::getDefinition() returns NULL). This allows
us to be a lot more lazy when parsing clang types and keeps down the amount
of data that gets parsed into the ASTContext for each module.
Getting the clang type from a "lldb_private::Type" object now takes a boolean
that indicates if a forward declaration is ok:
clang_type_t lldb_private::Type::GetClangType (bool forward_decl_is_ok);
So function prototypes that define parameters that are "const T&" can now just
parse the forward declaration for type 'T' and we avoid circular references in
the type system.
llvm-svn: 115012
Error in object runtime language detection code (spurious '; ')
Also replace false by NULL in a place where the compiler expects a pointer instead of a bool.
llvm-svn: 114957
- All single character options will now be printed together
- Changed all options that contains underscores to contain '-' instead
- Made the help come out a little flatter by showing the long and short
option on the same line.
- Modified the short character for "--ignore-count" options to "-i"
llvm-svn: 114265
SBValue to access it. For now this is just the result of ObjC NSPrintForDebugger,
but could be extended. Also store the results of the ObjC Object Printer in a
Stream, not a ConstString.
llvm-svn: 113660
function statics, file globals and static variables) that a frame contains.
The StackFrame objects can give out ValueObjects instances for
each variable which allows us to track when a variable changes and doesn't
depend on variable names when getting value objects.
StackFrame::GetVariableList now takes a boolean to indicate if we want to
get the frame compile unit globals and static variables.
The value objects in the stack frames can now correctly track when they have
been modified. There are a few more tweaks needed to complete this work. The
biggest issue is when stepping creates partial stacks (just frame zero usually)
and causes previous stack frames not to match up with the current stack frames
because the previous frames only has frame zero. We don't really want to
require that all previous frames be complete since stepping often must check
stack frames to complete their jobs. I will fix this issue tomorrow.
llvm-svn: 112800
defines that are in "llvm/Support/MachO.h". This should allow ObjectFileMachO
and ObjectContainerUniversalMachO to be able to be cross compiled in Linux.
Also did some cleanup on the ASTType by renaming it to ClangASTType and
renaming the header file. Moved a lot of "AST * + opaque clang type *"
functionality from lldb_private::Type over into ClangASTType.
llvm-svn: 109046
enabled LLVM make style building and made this compile LLDB on Mac OS X. We
can now iterate on this to make the build work on both linux and macosx.
llvm-svn: 108009