Commit Graph

21 Commits

Author SHA1 Message Date
Greg Clayton e72dfb321c <rdar://problem/10103468>
I started work on being able to add symbol files after a debug session
had started with a new "target symfile add" command and quickly ran into
problems with stale Address objects in breakpoint locations that had 
lldb_private::Section pointers into modules that had been removed or 
replaced. This also let to grabbing stale modules from those sections. 
So I needed to thread harded the Address, Section and related objects.

To do this I modified the ModuleChild class to now require a ModuleSP
on initialization so that a weak reference can created. I also changed
all places that were handing out "Section *" to have them hand out SectionSP.
All ObjectFile, SymbolFile and SymbolVendors were inheriting from ModuleChild
so all of the find plug-in, static creation function and constructors now
require ModuleSP references instead of Module *. 

Address objects now have weak references to their sections which can
safely go stale when a module gets destructed. 

This checkin doesn't complete the "target symfile add" command, but it
does get us a lot clioser to being able to do such things without a high
risk of crashing or memory corruption.

llvm-svn: 151336
2012-02-24 01:59:29 +00:00
Greg Clayton d9e416c0ea The second part in thread hardening the internals of LLDB where we make
the lldb_private::StackFrame objects hold onto a weak pointer to the thread
object. The lldb_private::StackFrame objects the the most volatile objects
we have as when we are doing single stepping, frames can often get lost or
thrown away, only to be re-created as another object that still refers to the
same frame. We have another bug tracking that. But we need to be able to 
have frames no longer be able to get the thread when they are not part of
a thread anymore, and this is the first step (this fix makes that possible
but doesn't implement it yet).

Also changed lldb_private::ExecutionContextScope to return shared pointers to
all objects in the execution context to further thread harden the internals.

llvm-svn: 150871
2012-02-18 05:35:26 +00:00
Greg Clayton e1cd1be6d6 Switching back to using std::tr1::shared_ptr. We originally switched away
due to RTTI worries since llvm and clang don't use RTTI, but I was able to 
switch back with no issues as far as I can tell. Once the RTTI issue wasn't
an issue, we were looking for a way to properly track weak pointers to objects
to solve some of the threading issues we have been running into which naturally
led us back to std::tr1::weak_ptr. We also wanted the ability to make a shared 
pointer from just a pointer, which is also easily solved using the 
std::tr1::enable_shared_from_this class. 

The main reason for this move back is so we can start properly having weak
references to objects. Currently a lldb_private::Thread class has a refrence
to its parent lldb_private::Process. This doesn't work well when we now hand
out a SBThread object that contains a shared pointer to a lldb_private::Thread
as this SBThread can be held onto by external clients and if they end up
using one of these objects we can easily crash.

So the next task is to start adopting std::tr1::weak_ptr where ever it makes
sense which we can do with lldb_private::Debugger, lldb_private::Target,
lldb_private::Process, lldb_private::Thread, lldb_private::StackFrame, and
many more objects now that they are no longer using intrusive ref counted
pointer objects (you can't do std::tr1::weak_ptr functionality with intrusive
pointers).

llvm-svn: 149207
2012-01-29 20:56:30 +00:00
Greg Clayton d1767f05b5 Added a new class called lldb_private::SymbolFileType which is designed to
take a SymbolFile reference and a lldb::user_id_t and be used in objects
which represent things in debug symbols that have types where we don't need
to know the true type yet, such as in lldb_private::Variable objects. This
allows us to defer resolving the type until something is used. More specifically
this allows us to get 1000 local variables from the current function, and if
the user types "frame variable argc", we end up _only_ resolving the type for
"argc" and not for the 999 other local variables. We can expand the use of this
as needed in the future.

Modified the DWARFMappedHash class to be able to read the HashData that has
more than just the DIE offset. It currently will read the atoms in the header
definition and read the data correctly. Currently only the DIE offset and 
type flags are supported. This is needed for adding type flags to the 
.apple_types hash accelerator tables.

Fixed a assertion crash that would happen if we have a variable that had a
DW_AT_const_value instead of a location where "location.LocationContains_DW_OP_addr()"
would end up asserting when it tried to parse the variable location as a
DWARF opcode list.

Decreased the amount of memory that LLDB would use when evaluating an expression
by 3x - 4x for clang. There was a place in the namespace lookup code that was
parsing all namespaces with a certain name in a DWARF file instead of stopping
when it found the first match. This was causing all of the compile units with
a matching namespace to get parsed into memory and causing unnecessary memory
bloat. 

Improved "Target::EvaluateExpression(...)" to not try and find a variable
when the expression contains characters that would certainly cause an expression
to need to be evaluated by the debugger. 

llvm-svn: 146130
2011-12-08 02:13:16 +00:00
Jason Molenda fd54b368ea Update declarations for all functions/methods that accept printf-style
stdarg formats to use __attribute__ format so the compiler can flag
incorrect uses.  Fix all incorrect uses.  Most of these are innocuous,
a few were resulting in crashes.

llvm-svn: 140185
2011-09-20 21:44:10 +00:00
Greg Clayton afacd14b0b Added the ability for DWARF locations to use the ABI plug-ins to resolve
register names when dumping variable locations and location lists. Also did
some cleanup where "int" types were being used for "lldb::RegisterKind"
values.

llvm-svn: 138988
2011-09-02 01:15:17 +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
Greg Clayton 45ba854399 Allow the built in ValueObject summary providers for C strings
use lldb_private::Target::ReadMemory(...) to allow constant strings
to be displayed in global variables prior on in between process
execution.

Centralized the variable declaration dumping into:

	bool
	Variable::DumpDeclaration (Stream *s, bool show_fullpaths, bool show_module);

Fixed an issue if you used "target variable --regex <regex>" where the
variable name would not be displayed, but the regular expression would.

Fixed an issue when viewing global variables through "target variable"
might not display correctly when doing DWARF in object files.

llvm-svn: 134878
2011-07-10 19:21:23 +00:00
Greg Clayton daf515fc8a Fixed the global and static variables to always be in scope.
Made it so that you can create synthetic children of array
value objects. This is for creating array members when the
array index is out of range. This comes in handy when you have
a structure definition like:

struct Collection
{
    uint32_t count;
    Item array[0];
};
"array" has 1 item, but many times in practice there are more
items in "item_array".

This allows you to do:

(lldb) target variable g_collection.array[3]

To implement this, the get child at index has been modified
to have a "ignore_array_bounds" boolean that can be set to true.

llvm-svn: 134846
2011-07-09 20:12:33 +00:00
Greg Clayton 884fb69460 Added the ability to see global variables with a variable expression path so
you can do things like:

(lldb) target variable g_global.a
(lldb) target variable *g_global.ptr
(lldb) target variable g_global.ptr[1]

llvm-svn: 134745
2011-07-08 21:46:14 +00:00
Greg Clayton 007d5be653 lldb-59.
llvm-svn: 132304
2011-05-30 00:49:24 +00:00
Greg Clayton 83c5cd9dfd Just like functions can have a basename and a mangled/demangled name, variable
can too. So now the lldb_private::Variable class has support for this.

Variables now have support for having a basename ("i"), and a mangled name 
("_ZN12_GLOBAL__N_11iE"), and a demangled name ("(anonymous namespace)::i").

Nowwhen searching for a variable by name, users might enter the fully qualified
name, or just the basename. So new test functions were added to the Variable 
and Mangled classes as:

	bool NameMatches (const ConstString &name);
	bool NameMatches (const RegularExpression &regex);

I also modified "ClangExpressionDeclMap::FindVariableInScope" to also search
for global variables that are not in the current file scope by first starting
with the current module, then moving on to all modules.

Fixed an issue in the DWARF parser that could cause a varaible to get parsed
more than once. Now, once we have parsed a VariableSP for a DIE, we cache
the result even if a variable wasn't made so we don't do any re-parsing. Some
DW_TAG_variable DIEs don't have locations, or are missing vital info that 
stops a debugger from being able to display anything for it, we parse a NULL
variable shared pointer for these DIEs so we don't keep trying to reparse it.

llvm-svn: 119085
2010-11-14 22:13:40 +00:00
Greg Clayton 247399230d Fixed C++ class clang type creation and display by making sure we omit
artifical members (like the vtable pointer member that shows up in the DWARF).
We were adding this to each class which was making all member variables be off
by a pointer size.

Added a test case so we can track this with "test/forward".

Fixed the type name index in DWARF to include all the types after finding
some types were being omitted due to the DW_AT_specification having the
DW_AT_declaration attribute which was being read into the real type instances
when there were forward declarations in the DWARF, causing the type to be
omitted. We now check to make sure any DW_AT_declaration values are only
respected when parsing types if the attribute is from the current DIE.

After fixing the missing types, we ran into some issues with the expression
parser finding duplicate entries for __va_list_tag since they are built in
types and would result in a "duplicate __va_list_tag definition" error. We
are now just ignoring this name during lookup, but we will need to see if
we can get the name lookup function to not get called in these cases.

Fixed an issue that would cause an assertion where DW_TAG_subroutine_types
that had no children, would not properly make a clang function type of:
"void (*) (void)".

llvm-svn: 116392
2010-10-13 03:15:28 +00:00
Greg Clayton 6dbd39838d Fixed a missing newline when dumping mixed disassembly.
Added a "bool show_fullpaths" to many more objects that were
previously always dumping full paths.

Fixed a few places where the DWARF was not indexed when we
we needed it to be when making queries. Also fixed an issue
where the DWARF in .o files wasn't searching all .o files
for the types.

Fixed an issue with the output from "image lookup --type <TYPENAME>"
where the name and byte size might not be resolved and might not
display. We now call the accessors so we end up seeing all of the
type info.

llvm-svn: 113951
2010-09-15 05:51:24 +00:00
Greg Clayton f5e56de080 Moved the section load list up into the target so we can use the target
to symbolicate things without the need for a valid process subclass.

llvm-svn: 113895
2010-09-14 23:36:40 +00:00
Greg Clayton 6f00abd546 Fixed the implementation of "bool Block::Contains (const Block *block) const"
to return the correct result.

Fixed "bool Variable::IsInScope (StackFrame *frame)" to return the correct
result when there are no location lists.

Modified the "frame variable" command such that:
- if no arguments are given (dump all frame variables), then we only show
  variables that are currently in scope
- if some arguments are given, we show an error if the variable is out of 
  scope

llvm-svn: 113830
2010-09-14 03:16:58 +00:00
Greg Clayton 016a95eb04 Looking at some of the test suite failures in DWARF in .o files with the
debug map showed that the location lists in the .o files needed some 
refactoring in order to work. The case that was failing was where a function
that was in the "__TEXT.__textcoal_nt" in the .o file, and in the 
"__TEXT.__text" section in the main executable. This made symbol lookup fail
due to the way we were finding a real address in the debug map which was
by finding the section that the function was in in the .o file and trying to
find this in the main executable. Now the section list supports finding a
linked address in a section or any child sections. After fixing this, we ran
into issue that were due to DWARF and how it represents locations lists. 
DWARF makes a list of address ranges and expressions that go along with those
address ranges. The location addresses are expressed in terms of a compile
unit address + offset. This works fine as long as nothing moves around. When
stuff moves around and offsets change between the remapped compile unit base
address and the new function address, then we can run into trouble. To deal
with this, we now store supply a location list slide amount to any location
list expressions that will allow us to make the location list addresses into
zero based offsets from the object that owns the location list (always a
function in our case). 

With these fixes we can now re-link random address ranges inside the debugger
for use with our DWARF + debug map, incremental linking, and more.

Another issue that arose when doing the DWARF in the .o files was that GCC
4.2 emits a ".debug_aranges" that only mentions functions that are externally
visible. This makes .debug_aranges useless to us and we now generate a real
address range lookup table in the DWARF parser at the same time as we index
the name tables (that are needed because .debug_pubnames is just as useless).
llvm-gcc doesn't generate a .debug_aranges section, though this could be 
fixed, we aren't going to rely upon it.

Renamed a bunch of "UINT_MAX" to "UINT32_MAX".

llvm-svn: 113829
2010-09-14 02:20:48 +00:00
Greg Clayton 59e8fc1c74 Clarified the intent of the SymbolContextScope class in the header
documentation. Symbol now inherits from the symbol
context scope so that the StackID can use a "SymbolContextScope *"
instead of a blockID (which could have been the same as some other
blockID from another symbol file). 

Modified the stacks that are created on subsequent stops to reuse
the previous stack frame objects which will allow for some internal
optimization using pointer comparisons during stepping. 

llvm-svn: 112495
2010-08-30 18:11:35 +00:00
Greg Clayton 9da7bd0739 Got a lot of the kinks worked out in the inline support after debugging more
complex inlined examples.

StackFrame classes don't have a "GetPC" anymore, they have "GetFrameCodeAddress()".
This is because inlined frames will have a PC value that is the same as the 
concrete frame that owns the inlined frame, yet the code locations for the
frame can be different. We also need to be able to get the real PC value for
a given frame so that variables evaluate correctly. To get the actual PC
value for a frame you can use:

    addr_t pc = frame->GetRegisterContext()->GetPC();

Some issues with the StackFrame stomping on its own symbol context were 
resolved which were causing the information to change for a frame when the
stack ID was calculated. Also the StackFrame will now correctly store the
symbol context resolve flags for any extra bits of information that were 
looked up (if you ask for a block only and you find one, you will alwasy have
the compile unit and function).

llvm-svn: 111964
2010-08-24 21:05:24 +00:00
Greg Clayton 0b76a2c21f Modified the host process monitor callback function Host::StartMonitoringChildProcess
to spawn a thread for each process that is being monitored. Previously
LLDB would spawn a single thread that would wait for any child process which
isn't ok to do as a shared library (LLDB.framework on Mac OSX, or lldb.so on
linux). The old single thread used to call wait4() with a pid of -1 which 
could cause it to reap child processes that it shouldn't have.

Re-wrote the way Function blocks are handles. Previously I attempted to keep
all blocks in a single memory allocation (in a std::vector). This made the
code somewhat efficient, but hard to work with. I got rid of the old BlockList
class, and went to a straight parent with children relationship. This new 
approach will allow for partial parsing of the blocks within a function.

llvm-svn: 111706
2010-08-21 02:22:51 +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