Commit Graph

274 Commits

Author SHA1 Message Date
Sean Callanan 912855fd27 Fixed LLDB's handling of ElaboratedTypes, which was
causing problems with printing the values of persistent
variables with struct types.

llvm-svn: 137392
2011-08-11 23:56:13 +00:00
Sean Callanan 5207a340e5 Fixed a problem that prevented access to members
of string literals ("hello"[2]).  Also fixed a
problem in which empty string literals were not
being compiled correctly ((int)printf("") would
print garbage).

Added a testcase that covers both.

llvm-svn: 137247
2011-08-10 21:05:52 +00:00
Greg Clayton 3418c85771 While tracking down memory consumption issue a few things were needed: the
ability to dump more information about modules in "target modules list". We
can now dump the shared pointer reference count for modules, the pointer to
the module itself (in case performance tools can help track down who has
references to said pointer), and the modification time.

Added "target delete [target-idx ...]" to be able to delete targets when they
are no longer needed. This will help track down memory usage issues and help 
to resolve when module ref counts keep getting incremented. If the command gets
no arguments, the currently selected target will be deleted. If any arguments 
are given, they must all be valid target indexes (use the "target list" 
command to get the current target indexes).

Took care of a bunch of "no newline at end of file" warnings.

TimeValue objects can now dump their time to a lldb_private::Stream object.

Modified the "target modules list --global" command to not error out if there
are no targets since it doesn't require a target.

Fixed an issue in the MacOSX DYLD dynamic loader plug-in where if a shared 
library was updated on disk, we would keep using the older one, even if it was
updated.

Don't allow the ModuleList::GetSharedModule(...) to return an empty module.
Previously we could specify a valid path on disc to a module, and specify an
architecture that wasn't contained in that module and get a shared pointer to
a module that wouldn't be able to return an object file or a symbol file. We
now make sure an object file can be extracted prior to adding the shared pointer
to the module to get added to the shared list.

llvm-svn: 137196
2011-08-10 02:10:13 +00:00
Johnny Chen ee7a359d59 Check log shared pointer before using it.
llvm-svn: 137173
2011-08-09 23:10:20 +00:00
Johnny Chen e95fcf7860 Check log shared pointer before using it.
llvm-svn: 137169
2011-08-09 22:52:27 +00:00
Jim Ingham 41c7591a1a Add EvaluateWithError static method. Fix a bug in handling constant expressions - we weren't setting the result even though the expression evaluation succeeded...
llvm-svn: 137077
2011-08-09 00:00:49 +00:00
Sean Callanan 69b5341c6a Made the expression parser use the StackFrame's
variable search API rather than rolling its own,
fixing one of our testcases.

llvm-svn: 137004
2011-08-06 00:28:14 +00:00
Sean Callanan 72e4940bd1 This is an overhaul of the expression parser code
that detects what context the current expression is
meant to execute in.  LLDB now properly consults
the method declaration in the debug information
rather than trying to hunt down the "this" or "self"
pointer by name, which can be misleading.

Other fixes include:

- LLDB now properly detects that it is inside
  an inlined C++ member function.

- LLDB now allows access to non-const members when
  in const code.

- The functions in SymbolFile that locate the
  DeclContext containing a DIE have been renamed
  to reflect what they actually do.  I have added
  new functions that find the DeclContext for the
  DIE itself.

I have also introduced testcases for C++ and 
Objective-C.

llvm-svn: 136999
2011-08-05 23:43:37 +00:00
Sean Callanan 0c4d8d25a7 Fixed a problem that caused LLDB to fail to execute
expressions that used function pointers.  The problem
was that IRForTarget previously only scanned the IR
for the expression for call instructions; if a function
was used in another context, it was ignored.

Now LLDB scans the Module for functions that are only
declared (not also defined -- so these are externals);
it then constructs function pointers for these
functions and substitutes them wherever the function
is used.

Also made some changes so that "expr main" works just
as well as "expr &main"; they end up being the same
code, but LLDB was generating the result variable in
different ways.

llvm-svn: 136928
2011-08-04 21:37:47 +00:00
Sean Callanan a789aa770e Improved the expression parser's detection of the
current context.  Previously, if there was a variable
called "self" available, the expression parser
assumed it was inside a method.  But class methods
in Objective-C also take a "self" parameter, of DWARF
type "id".  We now detect this properly, and only
assume we're in an instance method if "self" is a
pointer to an Objective-C object.

llvm-svn: 136784
2011-08-03 16:23:08 +00:00
Sean Callanan 7f3755b5ff Fixed a problem in the expression parser that
caused functions that were cast as part of the
call to have that cast ignored once their 
addresses were resolved.

Notably, in the case of objc_msgSend(), if
the function was cast from something returning
i8* to something returning i8, the expression
parser was discarding the cast as part of its
resolution.  This caused crashes later on.

llvm-svn: 136648
2011-08-01 20:53:53 +00:00
Sean Callanan b995119900 Added checking to make sure that the target has a
scratch AST context before attempting to parse.

llvm-svn: 136631
2011-08-01 18:18:33 +00:00
Sean Callanan af8e96c185 Fixed a bug where named constants were being
treated as externals, causing problems when we
tried to look their locations up in the debug
info.  For example:

expr char c[] = "foo"; c[0]

would terminate when trying to find c in the
debug information, despite the fact that c was
defined inside the expression.

llvm-svn: 136629
2011-08-01 17:41:38 +00:00
Peter Collingbourne eb72547f09 Add reloc arg to standard JIT createJIT()
Fixes non-__APPLE__ build.  Patch by Matt Johnson!

llvm-svn: 136580
2011-07-30 22:42:24 +00:00
Sean Callanan cc427fadec This change brings in the latest LLVM/Clang, and
completes the support in the LLDB expression parser
for incomplete types.  Clang now imports types
lazily, and we complete those types as necessary.

Changes include:

- ClangASTSource now supports three APIs which it
  passes to ClangExpressionDeclMap.  CompleteType
  completes a TagDecl or an ObjCInterfaceDecl when
  needed; FindExternalVisibleDecls finds named
  entities that are visible in the expression's
  scope; and FindExternalLexicalDecls performs a
  (potentially restricted) search for entities
  inside a lexical scope like a namespace.  These
  changes mean that entities in namespaces should
  work normally.

- The SymbolFileDWARF code for searching a context
  for a specific name is now more general, and can
  search arbitrary contexts.

- We are continuing to adapt our calls into LLVM
  from interfaces that take start and end iterators
  when accepting multiple items to interfaces that
  use ArrayRef.

- I have cleaned up some code, especially our use
  of namespaces.

This change is neutral for our testsuite and greatly
improves correctness for large programs (like Clang)
with complicated type systems.  It should also lay
the groundwork for improving the expression parser's
performance as we are lazier and lazier about
providing type information.

llvm-svn: 136555
2011-07-30 02:42:06 +00:00
Johnny Chen 4480530a0f Patch by Matt Johnson to silence G++ warnings!
Used hand merge to apply the diffs.  I did not apply the diffs for FormatManager.h and
the diffs for memberwise initialization for ValueObject.cpp because they changed since.
I will ask my colleague to apply them later.

llvm-svn: 135508
2011-07-19 19:48:13 +00:00
Enrico Granata 20edcdbe8a The implementation of categories is now synchronization safe
Code cleanup:
 - The Format Manager implementation is now split between two files: FormatClasses.{h|cpp} where the
   actual formatter classes (ValueFormat, SummaryFormat, ...) are implemented and
   FormatManager.{h|cpp} where the infrastructure classes (FormatNavigator, FormatManager, ...)
   are contained. The wrapper code always remains in Debugger.{h|cpp}
 - Several leftover fields, methods and comments from previous design choices have been removed
type category subcommands (enable, disable, delete) now can take a list of category names as input
 - for type category enable, saying "enable A B C" is the same as saying
    enable C
    enable B
    enable A
   (the ordering is relevant in enabling categories, and it is expected that a user typing
    enable A B C wants to look into category A, then into B, then into C and not the other
    way round)
 - for the other two commands, the order is not really relevant (however, the same inverted ordering
   is used for consistency)

llvm-svn: 135494
2011-07-19 18:03:25 +00:00
Sean Callanan 22c52d9a98 Removed a redundant dyn_cast. Thanks to Felipe
Cabecinhas.

llvm-svn: 135429
2011-07-18 21:30:18 +00:00
Greg Clayton c749eb89ad Added the ability to see block variables when looking up addresses
with the "target modules lookup --address <addr>" command. The variable
ID's, names, types, location for the address, and declaration is
displayed.

This can really help with crash logs since we get, on MacOSX at least,
the registers for the thread that crashed so it is often possible to
figure out some of the variable contents. 

llvm-svn: 134886
2011-07-11 05:12:02 +00:00
Jim Ingham 368c6301a2 remove errant parenthesis.
llvm-svn: 134717
2011-07-08 18:34:32 +00:00
Greg Clayton affb03b7fb Fixed a few issues where typedefs weren't passing through to the correct
recursive function.

Also fixed ClangASTContext::IsPointerType to correctly NULL out the pointee
handle if a valid one is provided.

llvm-svn: 134715
2011-07-08 18:27:39 +00:00
Sean Callanan 77eaf442ce Audited the expression parser to find uninitialized
pointers.  Some of the spots are obviously initialized
later, but it's better just to NULL the pointers out
at initialization to make the code more robust when
exposed to later changes.

llvm-svn: 134670
2011-07-08 00:39:14 +00:00
Sean Callanan c6466fc9ab Added checks to the expresssion parser which make
searching for variables and symbols in the target
more robust.  These checks prevent variables from
being reported as existing if they cannot actually
be evaluated in the current context.

llvm-svn: 134656
2011-07-07 23:05:43 +00:00
Greg Clayton 644247c1dc Added "target variable" command that allows introspection of global
variables prior to running your binary. Zero filled sections now get
section data correctly filled with zeroes when Target::ReadMemory
reads from the object file section data.

Added new option groups and option values for file lists. I still need
to hook up all of the options to "target variable" to allow more complete
introspection by file and shlib.

Added the ability for ValueObjectVariable objects to be created with
only the target as the execution context. This allows them to be read
from the object files through Target::ReadMemory(...). 

Added a "virtual Module * GetModule()" function to the ValueObject
class. By default it will look to the parent variable object and
return its module. The module is needed when we have global variables
that have file addresses (virtual addresses that are specific to
module object files) and in turn allows global variables to be displayed
prior to running.

Removed all of the unused proxy object support that bit rotted in 
lldb_private::Value.

Replaced a lot of places that used "FileSpec::Compare (lhs, rhs) == 0" code
with the more efficient "FileSpec::Equal (lhs, rhs)".

Improved logging in GDB remote plug-in.

llvm-svn: 134579
2011-07-07 01:59:51 +00:00
Greg Clayton dd0649bc5f Fixed an issue that was causing us to crash when evaluating expressions for
objective C or C++ methods when "self" or "this" were in scope, but had 
invalid locations in a DWARF location list. The lack of a valid value caused
us to use an invalid type value and then we tried to import that invalid 
value and we would crash.

llvm-svn: 134518
2011-07-06 18:55:08 +00:00
Greg Clayton e305594277 Centralize all of the type name code so that we always strip the leading
"struct ", "class ", and "union " from the start of any type names that are
extracted from clang QualType objects. I had to fix test suite cases that
were expecting the struct/union/class prefix to be there.

llvm-svn: 134132
2011-06-30 02:28:26 +00:00
Greg Clayton a2721476e7 This commit adds broad architectural support for hierarchical
inspection of namespaces in the expression parser.

ClangExpressionDeclMap hitherto reported that namespaces had
been completely imported, even though the namespaces are
returned empty.  To deal with this situation, ClangASTSource
was recently extended with an API to complete incomplete type
definitions, and, for greater efficiency, to complete these
definitions partially, returning only those objects that have
a given name.

This commit supports these APIs on LLDB's side, and uses it
to provide information on types resident in namespaces.
Namespaces are now imported as they were -- that is to say,
empty -- but with minimal import mode on.  This means that
Clang will come back and request their contents by name as
needed.  We now respond with information on the contained
types; this will be followed soon by information on functions
and variables.

llvm-svn: 133852
2011-06-25 00:44:06 +00:00
Greg Clayton 5fd05903d4 Cleanup error output on expressions.
llvm-svn: 133834
2011-06-24 22:31:10 +00:00
Greg Clayton 084db10d4d Fixed an issue for ARM where data symbols would alway return invalid addresses.
llvm-svn: 133684
2011-06-23 04:25:29 +00:00
Jim Ingham f72ce3a216 Use the dyld_mode, image_infos & image_infos_count passed into the shared library notification function
to update libraries rather than reading the whole all_imaage_infos structure every time we get notified.

llvm-svn: 133448
2011-06-20 17:32:44 +00:00
Peter Collingbourne 1740be7cd9 Disable MCJIT on non-Darwin platforms
Currently the runtime dynamic linker lacks object file support for anything
other than Mach-O.

llvm-svn: 132583
2011-06-03 20:40:12 +00:00
Greg Clayton 007d5be653 lldb-59.
llvm-svn: 132304
2011-05-30 00:49:24 +00:00
Greg Clayton 9b72eb7101 ABI plug-ins must implement the following pure virtual functions:
virtual bool
ABI::StackUsesFrames () = 0;

Should return true if your ABI uses frames when doing stack backtraces. This
means a frame pointer is used that points to the previous stack frame in some
way or another.

virtual bool
ABI::CallFrameAddressIsValid (lldb::addr_t cfa) = 0;

Should take a look at a call frame address (CFA) which is just the stack
pointer value upon entry to a function. ABIs usually impose alignment
restrictions (4, 8 or 16 byte aligned), and zero is usually not allowed.
This function should return true if "cfa" is valid call frame address for
the ABI, and false otherwise. This is used by the generic stack frame unwinding
code to help determine when a stack ends.

virtual bool
ABI::CodeAddressIsValid (lldb::addr_t pc) = 0;    

Validates a possible PC value and returns true if an opcode can be at "pc".
Some ABIs or architectures have fixed width instructions and must be aligned
to a 2 or 4 byte boundary. "pc" can be an opcode or a callable address which
means the load address might be decorated with extra bits (such as bit zero
to indicate a thumb function call for ARM targets), so take this into account
when returning true or false. The address should also be validated to ensure
it is a valid address for the address size of the inferior process. 32 bit
targets should make sure the address is less than UINT32_MAX.

Modified UnwindLLDB to use the new ABI functions to help it properly terminate
stacks.


Modified the mach-o function that extracts dependent files to not resolve the
path as the paths inside a binary might not match those on the current
host system.

llvm-svn: 132021
2011-05-24 23:06:02 +00:00
Sean Callanan 79763a42ab This commit integrates support for the LLVM MCJIT
into the mainline LLDB codebase.  MCJIT introduces
API improvements and better architectural support.

This commit adds a new subsystem, the
ProcessDataAllocator, which is responsible for
performing static data allocations on behalf of the
IR transformer.  MCJIT currently does not support
the relocations required to store the constant pool
in the same allocation as the function body, so we
allocate a heap region separately and redirect
static data references from the expression to that
heap region in a new IR modification pass.

This patch also fixes bugs in the IR
transformations that were exposed by the transition
to the MCJIT.  Finally, the patch also pulls in a
more recent revision of LLVM so that the MCJIT is
available for use.

llvm-svn: 131923
2011-05-23 21:40:23 +00:00
Greg Clayton f3ef3d2af9 Added new lldb_private::Process memory read/write functions to stop a bunch
of duplicated code from appearing all over LLDB:

lldb::addr_t
Process::ReadPointerFromMemory (lldb::addr_t vm_addr, Error &error);

bool
Process::WritePointerToMemory (lldb::addr_t vm_addr, lldb::addr_t ptr_value, Error &error);

size_t
Process::ReadScalarIntegerFromMemory (lldb::addr_t addr, uint32_t byte_size, bool is_signed, Scalar &scalar, Error &error);

size_t
Process::WriteScalarToMemory (lldb::addr_t vm_addr, const Scalar &scalar, uint32_t size, Error &error);

in lldb_private::Process the following functions were renamed:

From:
uint64_t
Process::ReadUnsignedInteger (lldb::addr_t load_addr, 
                              size_t byte_size,
                              Error &error);

To:
uint64_t
Process::ReadUnsignedIntegerFromMemory (lldb::addr_t load_addr, 
                                        size_t byte_size,
                                        uint64_t fail_value, 
                                        Error &error);

Cleaned up a lot of code that was manually doing what the above functions do
to use the functions listed above.

Added the ability to get a scalar value as a buffer that can be written down
to a process (byte swapping the Scalar value if needed):

uint32_t 
Scalar::GetAsMemoryData (void *dst,
                        uint32_t dst_len, 
                        lldb::ByteOrder dst_byte_order,
                        Error &error) const;

The "dst_len" can be smaller that the size of the scalar and the least 
significant bytes will be written. "dst_len" can also be larger and the
most significant bytes will be padded with zeroes. 

Centralized the code that adds or removes address bits for callable and opcode
addresses into lldb_private::Target:

lldb::addr_t
Target::GetCallableLoadAddress (lldb::addr_t load_addr, AddressClass addr_class) const;

lldb::addr_t
Target::GetOpcodeLoadAddress (lldb::addr_t load_addr, AddressClass addr_class) const;

All necessary lldb_private::Address functions now use the target versions so
changes should only need to happen in one place if anything needs updating.

Fixed up a lot of places that were calling :

addr_t
Address::GetLoadAddress(Target*);

to call the Address::GetCallableLoadAddress() or Address::GetOpcodeLoadAddress()
as needed. There were many places in the breakpoint code where things could
go wrong for ARM if these weren't used.

llvm-svn: 131878
2011-05-22 22:46:53 +00:00
Greg Clayton 3f5c08f5c2 Added a function to lldb_private::Address:
addr_t
        Address::GetCallableLoadAddress (Target *target) const;
        
This will resolve the load address in the Address object and optionally
decorate the address up to be able to be called. For all non ARM targets, this
just essentially returns the result of "Address::GetLoadAddress (target)". But
for ARM targets, it checks if the address is Thumb, and if so, it returns
an address with bit zero set to indicate a mode switch to Thumb. This is how
we need function pointers to be for return addresses and when resolving 
function addresses for the JIT. It is also nice to centralize this in one spot
to avoid having multiple copies of this code.

llvm-svn: 131588
2011-05-18 22:01:49 +00:00
Jim Ingham 17e5c4e261 RunThreadPlan should set the plan to "not private" since it needs that,
and then reset it to the original value when done.

llvm-svn: 131498
2011-05-17 22:24:54 +00:00
Greg Clayton e6a9e439d4 Fixed the "mmap" to work on MacOSX/darwin by supplying the correct arguemnts.
Modified ClangUserExpression and ClangUtilityFunction to display the actual
error (if one is available) that made the JIT fail instead of a canned 
response.

Fixed the restoring of all register values when the 'G' packet doesn't work
to use the correct data.

llvm-svn: 131454
2011-05-17 03:51:29 +00:00
Jim Ingham 160f78c584 Fix the error message when an expression evaluation is interrupted by a crash/breakpoint hit to
give the reason for the interrupt. Also make sure it we don't want to unwind from the evaluation
we print something if it is interrupted.

llvm-svn: 131448
2011-05-17 01:10:11 +00:00
Greg Clayton 1cfca1dc09 Dump JIT memory requirements when "log enable lldb expr" logging is enabled.
Correctly handle invalid 32-bit mmap fail return value in ProcessGDBRemote.

llvm-svn: 131394
2011-05-15 23:56:52 +00:00
Sean Callanan d12cf8bbc9 Updated to use the latest LLVM/Clang, to pick up JIT
changes.

llvm-svn: 131391
2011-05-15 22:34:38 +00:00
Greg Clayton 70b5765740 Added the ability to get the return value from a ThreadPlanCallFunction
thread plan. In order to get the return value, you can call:

        void
        ThreadPlanCallFunction::RequestReturnValue (lldb::ValueSP &return_value_sp);
        
This registers a shared pointer to a return value that will get filled in if
everything goes well. After the thread plan is run the return value will be
extracted for you.

Added an ifdef to be able to switch between the LLVM MCJIT and the standand JIT.
We currently have the standard JIT selected because we have some work to do to
get the MCJIT fuctioning properly.

Added the ability to call functions with 6 argument in the x86_64 ABI.

Added the ability for GDBRemoteCommunicationClient to detect if the allocate
and deallocate memory packets are supported and to not call allocate memory 
("_M") or deallocate ("_m") if we find they aren't supported.

Modified the ProcessGDBRemote::DoAllocateMemory(...) and ProcessGDBRemote::DoDeallocateMemory(...) 
to be able to deal with the allocate and deallocate memory packets not being 
supported. If they are not supported, ProcessGDBRemote will switch to calling
"mmap" and "munmap" to allocate and deallocate memory instead using our 
trivial function call support.

Modified the "void ProcessGDBRemote::DidLaunchOrAttach()" to correctly ignore 
the qHostInfo triple information if any was specified in the target. Currently 
if the target only specifies an architecture when creating the target:

(lldb) target create --arch i386 a.out

Then the vendor, os and environemnt will be adopted by the target.

If the target was created with any triple that specifies more than the arch:

(lldb) target create --arch i386-unknown-unknown a.out

Then the target will maintain its triple and not adopt any new values. This
can be used to help force bare board debugging where the dynamic loader for
static files will get used and users can then use "target modules load ..."
to set addressses for any files that are desired.

Added back some convenience functions to the lldb_private::RegisterContext class
for writing registers with unsigned values. Also made all RegisterContext
constructors explicit to make sure we know when an integer is being converted
to a RegisterValue. 

llvm-svn: 131370
2011-05-15 01:25:55 +00:00
Sean Callanan 19b6afe35e For cases where a const function is inaccurately reported
as non-const in the debug information, added a fallback
to GetFunctionAddress, adding the const qualifier after
the fact and searching again.

llvm-svn: 131299
2011-05-13 18:27:02 +00:00
Sean Callanan 775022652b Introduced support for UnknownAnyTy, the Clang type
representing variables whose type must be inferred
from the way they are used.  Functions without debug
information now return UnknownAnyTy and must be cast.

Variables with no debug information are not yet using
UnknownAnyTy; instead they are assumed to be void*.
Support for variables of unknown type is coming (and,
in fact, some relevant support functions are included
in this commit) but will take a bit of extra effort.

The testsuite has also been updated to reflect the new
requirement that the result of printf be cast, i.e.

expr (int) printf("Hello world!")

llvm-svn: 131263
2011-05-12 23:54:16 +00:00
Sean Callanan e359d9b771 Fixed a bug in which expression-local variables were
treated as being permanently resident in target
memory.  In fact, since the expression's stack frame
is deleted and potentially re-used after the
expression completes, the variables need to be treated
as being freeze-dried.

llvm-svn: 131104
2011-05-09 22:04:36 +00:00
Greg Clayton 7349bd9078 While implementing unwind information using UnwindAssemblyInstEmulation I ran
into some cleanup I have been wanting to do when reading/writing registers.
Previously all RegisterContext subclasses would need to implement:

virtual bool
ReadRegisterBytes (uint32_t reg, DataExtractor &data);

virtual bool
WriteRegisterBytes (uint32_t reg, DataExtractor &data, uint32_t data_offset = 0);

There is now a new class specifically designed to hold register values: 
        lldb_private::RegisterValue
        
The new register context calls that subclasses must implement are:

virtual bool
ReadRegister (const RegisterInfo *reg_info, RegisterValue &reg_value) = 0;

virtual bool
WriteRegister (const RegisterInfo *reg_info, const RegisterValue &reg_value) = 0;

The RegisterValue class must be big enough to handle any register value. The
class contains an enumeration for the value type, and then a union for the 
data value. Any integer/float values are stored directly in an appropriate
host integer/float. Anything bigger is stored in a byte buffer that has a length
and byte order. The RegisterValue class also knows how to copy register value
bytes into in a buffer with a specified byte order which can be used to write
the register value down into memory, and this does the right thing when not
all bytes from the register values are needed (getting a uint8 from a uint32
register value..). 

All RegiterContext and other sources have been switched over to using the new
regiter value class.

llvm-svn: 131096
2011-05-09 20:18:18 +00:00
Sean Callanan d9ca42aa4f Added support for reading untyped symbols. Right now
they are treated as pointers of type (void*).  This
allows reading of environ, for instance.

llvm-svn: 131063
2011-05-08 02:21:26 +00:00
Sean Callanan 63697e5025 Made expressions that are just casts of pointer
variables be evaluated statically.

Also fixed a bug that caused the results of
statically-evaluated expressions to be materialized
improperly.

This bug also removes some duplicate code.

llvm-svn: 131042
2011-05-07 01:06:41 +00:00
Jim Ingham 61be0903e5 Adding support for fetching the Dynamic Value for ObjC Objects.
llvm-svn: 130701
2011-05-02 18:13:59 +00:00
Jim Ingham 58b59f9522 Fix up how the ValueObjects manage their life cycle so that you can hand out a shared
pointer to a ValueObject or any of its dependent ValueObjects, and the whole cluster will
stay around as long as that shared pointer stays around.

llvm-svn: 130035
2011-04-22 23:53:53 +00:00