Commit Graph

12 Commits

Author SHA1 Message Date
Greg Clayton 5ccbd294b2 Fixed issues with RegisterContext classes and the subclasses. There was
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
2011-01-06 22:15:06 +00:00
Sean Callanan ed85f908d6 Fixed the handling of the _cmd parameter in the i386
ABI.

llvm-svn: 122118
2010-12-18 00:32:25 +00:00
Sean Callanan 9d48e80426 Bugfixes for the new "self" pointer handling. Specifically,
the code to pass the _cmd pointer has been improved, and _cmd
is now set to the value of _cmd for the current context, as
opposed to being simply NULL.

llvm-svn: 121739
2010-12-14 00:42:36 +00:00
Sean Callanan 1782783095 Added support for generating expressions that have
access to the members of the Objective-C self object.

The approach we take is to generate the method as a
@category on top of the self object, and to pass the
"self" pointer to it.  (_cmd is currently NULL.)

Most changes are in ClangExpressionDeclMap, but the
change that adds support to the ABIs to pass _cmd
touches a fair amount of code.

llvm-svn: 121722
2010-12-13 22:46:15 +00:00
Greg Clayton 526e5afb2d Modified the lldb_private::Type clang type resolving code to handle three
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
2010-11-13 03:52:47 +00:00
Greg Clayton 1be10fca5f Fixed the forward declaration issue that was present in the DWARF parser after
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
2010-09-29 01:12:09 +00:00
Sean Callanan fc55f5d1b0 Removed the hacky "#define this ___clang_this" handler
for C++ classes.  Replaced it with a less hacky approach:

 - If an expression is defined in the context of a
   method of class A, then that expression is wrapped as
   ___clang_class::___clang_expr(void*) { ... }
   instead of ___clang_expr(void*) { ... }.

 - ___clang_class is resolved as the type of the target
   of the "this" pointer in the method the expression
   is defined in.

 - When reporting the type of ___clang_class, a method
   with the signature ___clang_expr(void*) is added to
   that class, so that Clang doesn't complain about a
   method being defined without a corresponding
   declaration.

 - Whenever the expression gets called, "this" gets
   looked up, type-checked, and then passed in as the
   first argument.

This required the following changes:

 - The ABIs were changed to support passing of the "this"
   pointer as part of trivial calls.

 - ThreadPlanCallFunction and ClangFunction were changed
   to support passing of an optional "this" pointer.

 - ClangUserExpression was extended to perform the
   wrapping described above.

 - ClangASTSource was changed to revert the changes
   required by the hack.

 - ClangExpressionParser, IRForTarget, and
   ClangExpressionDeclMap were changed to handle
   different manglings of ___clang_expr flexibly.  This
   meant no longer searching for a function called
   ___clang_expr, but rather looking for a function whose
   name *contains* ___clang_expr.

 - ClangExpressionParser and ClangExpressionDeclMap now
   remember whether "this" is required, and know how to
   look it up as necessary.

A few inheritance bugs remain, and I'm trying to resolve
these.  But it is now possible to use "this" as well as
refer implicitly to member variables, when in the proper
context.

llvm-svn: 114384
2010-09-21 00:44:12 +00:00
Jason Molenda fbcb7f2c4e The first part of an lldb native stack unwinder.
The Unwind and RegisterContext subclasses still need
to be finished; none of this code is used by lldb at
this point (unless you call into it by hand).

The ObjectFile class now has an UnwindTable object.

The UnwindTable object has a series of FuncUnwinders
objects (Function Unwinders) -- one for each function
in that ObjectFile we've backtraced through during this
debug session.

The FuncUnwinders object has a few different UnwindPlans.
UnwindPlans are a generic way of describing how to find
the canonical address of a given function's stack frame
(the CFA idea from DWARF/eh_frame) and how to restore the
caller frame's register values, if they have been saved
by this function.

UnwindPlans are created from different sources.  One source is the
eh_frame exception handling information generated by the compiler
for unwinding an exception throw.  Another source is an assembly
language inspection class (UnwindAssemblyProfiler, uses the Plugin
architecture) which looks at the instructions in the funciton
prologue and describes the stack movements/register saves that are
done.

Two additional types of UnwindPlans that are worth noting are
the "fast" stack UnwindPlan which is useful for making a first
pass over a thread's stack, determining how many stack frames there
are and retrieving the pc and CFA values for each frame (enough
to create StackFrameIDs).  Only a minimal set of registers is
recovered during a fast stack walk.  

The final UnwindPlan is an architectural default unwind plan.
These are provided by the ArchDefaultUnwindPlan class (which uses
the plugin architecture).  When no symbol/function address range can
be found for a given pc value -- when we have no eh_frame information
and when we don't have a start address so we can't examine the assembly
language instrucitons -- we have to make a best guess about how to 
unwind.  That's when we use the architectural default UnwindPlan.
On x86_64, this would be to assume that rbp is used as a stack pointer
and we can use that to find the caller's frame pointer and pc value.
It's a last-ditch best guess about how to unwind out of a frame.

There are heuristics about when to use one UnwindPlan versues the other --
this will all happen in the still-begin-written UnwindLLDB subclass of
Unwind which runs the UnwindPlans.

llvm-svn: 113581
2010-09-10 07:49:16 +00:00
Sean Callanan d0d37d1800 Updated the x86_64 and i386 ABIs to chain RBP
(i.e., leave the value the same, so that a new
stack frame will be linked to the previous
stack) rather than zeroing out RBP.

This fixes calls to dlopen(), for example, which
does a backtrace to see which image is calling
it.

llvm-svn: 113288
2010-09-07 21:23:34 +00:00
Greg Clayton b0b9fe610a Added support for objective C built-in types: id, Class, and SEL. This
involved watching for the objective C built-in types in DWARF and making sure
when we convert the DWARF types into clang types that we use the appropriate
ASTContext types.

Added a way to find and dump types in lldb (something equivalent to gdb's 
"ptype" command):

    image lookup --type <TYPENAME>

This only works for looking up types by name and won't work with variables.
It also currently dumps out verbose internal information. I will modify it
to dump more appropriate user level info in my next submission.

Hookup up the "FindTypes()" functions in the SymbolFile and SymbolVendor so
we can lookup types by name in one or more images.

Fixed "image lookup --address <ADDRESS>" to be able to correctly show all
symbol context information, but it will only show this extra information when
the new "--verbose" flag is used.

Updated to latest LLVM to get a few needed fixes.

llvm-svn: 110089
2010-08-03 00:35:52 +00:00
Greg Clayton c982c768d2 Merged Eli Friedman's linux build changes where he added Makefile files that
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
2010-07-09 20:39:50 +00:00
Chris Lattner 30fdc8d841 Initial checkin of lldb code from internal Apple repo.
llvm-svn: 105619
2010-06-08 16:52:24 +00:00