Full UnwindPlan is trying to do an impossible unwind; in that case
invalidate the Full UnwindPlan and replace it with the architecture
default unwind plan.
This is a scenario that happens occasionally with arm unwinds in
particular; the instruction analysis based full unwindplan can
mis-parse the functions and the stack walk stops prematurely. Now
we can do a simpleminded frame-chain walk to find the caller frame
and continue the unwind. It's not ideal but given the complicated
nature of analyzing the arm functions, and the lack of eh_frame
information on iOS, it is a distinct improvement and fixes some
long-standing problems with the unwinder on that platform.
This is fixing <rdar://problem/12091421>. I may re-use this
invalidate feature in the future if I can identify other cases where
the full unwindplan's unwind information is clearly incorrect.
This checkin also includes some cleanup for the volatile register
definition in the arm ABI plugin for <rdar://problem/10652166>
although work remains to be done for that bug.
llvm-svn: 166757
Added new API to lldb::SBTypeMember for bitfields:
bool SBTypeMember::IsBitfield();
uint32_t SBTypeMember::GetBitfieldSizeInBits();
Also added new properties for easy access. Now SBTypeMember objects in python have a "fields" property for all type fields, "bases" for all direct bases, "vbases" for all virtual base classes and "members" for a combo of all three organized by bit offset. They all return a python list() of SBTypeMember objects. Usage:
(lldb) script
>>> t = lldb.target.FindFirstType("my_type")
>>> for field in t.fields:
... print field
>>> for vbase in t.vbases:
... print vbase
>>> for base in t.bases:
... print base
>>> for member in t.members:
... print member
Also added new "is_bitfield" property to the SBTypeMember objects that will return the result of SBTypeMember::IsBitfield(), and "bitfield_bit_size" which will return the result of SBTypeMember::GetBitfieldSizeInBits();
I also fixed "SBTypeMember::GetOffsetInBytes()" to return the correct byte offset.
llvm-svn: 161091
a shared pointer to ease some memory management issues with a patch
I'm working on.
The main complication with using SPs for these objects is that most
methods that build up an UnwindPlan will construct a Row to a given
instruction point in a function, then add additional regsaves in
the next instruction point to that row and push it again. A little
care is needed to not mutate the previous instruction point's Row
once these are switched to being held behing shared pointers.
llvm-svn: 160214
Initial step -- infrastructure change -- to fix the bug. Change the RegisterInfo data structure
to contain two additional fields (uint32_t *value_rges and uint32_t *invalidate_regs) to facilitate
architectures which have register mapping.
Update all existing RegsiterInfo arrays to have two extra NULL's (the additional fields) in each row,
GDBRemoteRegisterContext.cpp is modified to add d0-d15 and q0-q15 register info entries which take
advantage of the value_regs field to specify the containment relationship:
d0 -> (s0, s1)
...
d15 -> (s30, s31)
q0 -> (d0, d1)
...
q15 -> (d30, d31)
llvm-svn: 151686
objects for the backlink to the lldb_private::Process. The issues we were
running into before was someone was holding onto a shared pointer to a
lldb_private::Thread for too long, and the lldb_private::Process parent object
would get destroyed and the lldb_private::Thread had a "Process &m_process"
member which would just treat whatever memory that used to be a Process as a
valid Process. This was mostly happening for lldb_private::StackFrame objects
that had a member like "Thread &m_thread". So this completes the internal
strong/weak changes.
Documented the ExecutionContext and ExecutionContextRef classes so that our
LLDB developers can understand when and where to use ExecutionContext and
ExecutionContextRef objects.
llvm-svn: 151009
Switch from GetReturnValue, which was hardly ever used, to GetReturnValueObject
which is much more convenient.
Return the "return value object" as a persistent variable if requested.
llvm-svn: 147157
UnwindPlan for unwinding from the first instruction of an otherwise
unknown function call (GetUnwindPlanArchitectureDefaultAtFunctionEntry()).
Update RegisterContextLLDB::GetFullUnwindPlanForFrame() to detect the
case of a frame 0 at address 0x0 which indicates that we jumped through
a NULL function pointer. Use the ABI's FunctionEntryUnwindPlan to
find the caller frame.
These changes make it so lldb can identify the calling frame correctly
in code like
int main ()
{
void (*f)(void) = 0;
f();
}
llvm-svn: 139760
plug-ins are add on plug-ins for the lldb_private::Process class that can add
thread contexts that are read from memory. It is common in kernels to have
a lot of threads that are not currently executing on any cores (JTAG debugging
also follows this sort of thing) and are context switched out whose state is
stored in memory data structures. Clients can now subclass the OperatingSystem
plug-ins and then make sure their Create functions correcltly only enable
themselves when the right binary/target triple are being debugged. The
operating system plug-ins get a chance to attach themselves to processes just
after launching or attaching and are given a lldb_private::Process object
pointer which can be inspected to see if the main executable, target triple,
or any shared libraries match a case where the OS plug-in should be used.
Currently the OS plug-ins can create new threads, define the register contexts
for these threads (which can all be different if desired), and populate and
manage the thread info (stop reason, registers in the register context) as
the debug session goes on.
llvm-svn: 138228
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
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
pointers:
virtual bool
PrepareTrivialCall (Thread &thread,
lldb::addr_t sp,
lldb::addr_t functionAddress,
lldb::addr_t returnAddress,
lldb::addr_t *arg1_ptr,
lldb::addr_t *arg2_ptr,
lldb::addr_t *arg3_ptr) const = 0;
Prior to this it was:
virtual bool
PrepareTrivialCall (Thread &thread,
lldb::addr_t sp,
lldb::addr_t functionAddress,
lldb::addr_t returnAddress,
lldb::addr_t arg,
lldb::addr_t *this_arg,
lldb::addr_t *cmd_arg) const = 0;
This was because the function that called this slowly added more features to
be able to call a C++ member function that might have a "this" pointer, and
then later added "self + cmd" support for objective C. Cleaning this code up
and the code that calls it makes it easier to implement the functions for
new targets.
The MacOSX_arm::PrepareTrivialCall() is now filled in and ready for testing.
llvm-svn: 131221
respective ABI plugins as they were plug-ins that supplied ABI specfic info.
Also hookep up the UnwindAssemblyInstEmulation so that it can generate the
unwind plans for ARM.
Changed the way ABI plug-ins are handed out when you get an instance from
the plug-in manager. They used to return pointers that would be mananged
individually by each client that requested them, but now they are handed out
as shared pointers since there is no state in the ABI objects, they can be
shared.
llvm-svn: 131193
an interface to a local or remote debugging platform. By default each host OS
that supports LLDB should be registering a "default" platform that will be
used unless a new platform is selected. Platforms are responsible for things
such as:
- getting process information by name or by processs ID
- finding platform files. This is useful for remote debugging where there is
an SDK with files that might already or need to be cached for debug access.
- getting a list of platform supported architectures in the exact order they
should be selected. This helps the native x86 platform on MacOSX select the
correct x86_64/i386 slice from universal binaries.
- Connect to remote platforms for remote debugging
- Resolving an executable including finding an executable inside platform
specific bundles (macosx uses .app bundles that contain files) and also
selecting the appropriate slice of universal files for a given platform.
So by default there is always a local platform, but remote platforms can be
connected to. I will soon be adding a new "platform" command that will support
the following commands:
(lldb) platform connect --name machine1 macosx connect://host:port
Connected to "machine1" platform.
(lldb) platform disconnect macosx
This allows LLDB to be well setup to do remote debugging and also once
connected process listing and finding for things like:
(lldb) process attach --name x<TAB>
The currently selected platform plug-in can now auto complete any available
processes that start with "x". The responsibilities for the platform plug-in
will soon grow and expand.
llvm-svn: 127286
now, in addition to cpu type/subtype and architecture flavor, contains:
- byte order (big endian, little endian)
- address size in bytes
- llvm::Triple for true target triple support and for more powerful plug-in
selection.
llvm-svn: 125602
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
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
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
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
don't crash if we disable logging when some code already has a copy of the
logger. Prior to this fix, logs were handed out as pointers and if they were
held onto while a log got disabled, then it could cause a crash. Now all logs
are handed out as shared pointers so this problem shouldn't happen anymore.
We are also using our new shared pointers that put the shared pointer count
and the object into the same allocation for a tad better performance.
llvm-svn: 118319
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
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
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
(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
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
Jason Molenda