When a process stops due to a crash, we get the crashing instruction and the
crashing memory location (if there is one). From the user's perspective it is
often unclear what the reason for the crash is in a symbolic sense.
To address this, I have added new fuctionality to StackFrame to parse the
disassembly and reconstruct the sequence of dereferneces and offsets that were
applied to a known variable (or fuction retrn value) to obtain the invalid
pointer.
This makes use of enhancements in the disassembler, as well as new information
provided by the DWARF expression infrastructure, and is exposed through a
"frame diagnose" command. It is also used to provide symbolic information, when
available, in the event of a crash.
The algorithm is very rudimentary, and it needs a bunch of work, including
- better parsing for assembly, preferably with help from LLVM
- support for non-Apple platforms
- cleanup of the algorithm core, preferably to make it all work in terms of
Operands instead of register/offset pairs
- improvement of the GetExpressioPath() logic to make prettier expression
paths, and
- better handling of vtables.
I welcome all suggestios, improvements, and testcases.
llvm-svn: 280692
Rules are as follows for internal code using lldb::DisassemblerSP and lldb::InstructionSP:
1 - The disassembler needs to stay around as long as instructions do as the Instruction subclass now has a weak pointer to the disassembler
2 - The public API has been fixed so that if you get a SBInstruction, it will hold onto a strong reference to the disassembler in a new InstructionImpl class
This will keep code like like:
inst = lldb.target.ReadInstructions(frame.GetPCAddress(), 1).GetInstructionAtIndex(0)
inst.GetMnemonic()
Working as expected (not the SBInstructionList() that was returned by SBTarget.ReadInstructions() is gone, but "inst" has a strong reference inside of it to the disassembler and the instruction.
All code inside the LLDB shared library was verified to correctly hold onto the disassembler instance in all places.
<rdar://problem/24585496>
llvm-svn: 272069
This is a pretty straightforward first pass over removing a number of uses of
Mutex in favor of std::mutex or std::recursive_mutex. The problem is that there
are interfaces which take Mutex::Locker & to lock internal locks. This patch
cleans up most of the easy cases. The only non-trivial change is in
CommandObjectTarget.cpp where a Mutex::Locker was split into two.
llvm-svn: 269877
in thumb mode into one method in ArchSpec, replace checks for
specific cores in the disassembler with calls to this. Also call
this from the arm instruction emulation code.
The determination of whether a given ArchSpec is thumb-only is still
a bit of a hack, but at least the hack is consolidated into a single
place. In my original version of this patch http://reviews.llvm.org/D13578
I was calling into llvm's feature arm feature tables to make this
determination, like
#include "llvm/Support/TargetRegistry.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/../../lib/Target/ARM/ARMGenRegisterInfo.inc"
#include "llvm/../../lib/Target/ARM/ARMFeatures.h"
[...]
std::string triple (GetTriple().getTriple());
const char *cpu = "";
const char *features_str = "";
const llvm::Target *curr_target = llvm::TargetRegistry::lookupTarget(triple.c_str(), Error);
std::unique_ptr<llvm::MCSubtargetInfo> subtarget_info_up (curr_target->createMCSubtargetInfo(triple.c_str(), cpu, features_str));
if (subtarget_info_up->getFeatureBits()[llvm::ARM::FeatureNoARM])
{
return true;
}
but those tables are post-llvm-build generated and linking against them
for all of our different build system methods was a big hiccup that I
haven't had time to revisit convincingly.
I'll keep that reviews.llvm.org patch around to remind myself that I
need to take another run at linking against the necessary tables
again in llvm.
<rdar://problem/23022803>
llvm-svn: 265377
Previously we were using thumbv7 and armv8.1a what ended up showing a
few undefined instruction when disassembling code. This CL update the
architectures used to armv8.2a and thumbv8.2a (newest available) so we
display all instruction in the disassambly.
llvm-svn: 262482
when they introduced android testsuite regressions. Pavel has run the
testsuite against the updated patch and it completes cleanly now.
The original commit message:
Fixing a subtle issue on Mac OS X systems with dSYMs (possibly
introduced by r235737 but I didn't look into it too closely).
A dSYM can have a per-UUID plist in it which tells lldb where
to find an executable binary for the dSYM (DBGSymbolRichExecutable)
- other information can be included in this plist, like how to
remap the source file paths from their build pathnames to their
long-term storage pathnames.
This per-UUID plist is a unusual; it is used probably exclusively
inside apple with our build system. It is not created by default
in normal dSYMs.
The problem was like this:
1. lldb wants to find an executable, given only a UUID
(this happens when lldb is doing cross-host debugging
and doesn't have a copy of the target system's binaries)
2. It eventually calls LocateMacOSXFilesUsingDebugSymbols
which does a spotlight search for the dSYM on the local
system, and failing that, tries the DBGShellCommands
command to find the dSYM.
3. It gets a dSYM. It reads the per-UUID plist in the dSYM.
The dSYM has a DBGSymbolRichExecutable kv pair pointing to
the binary on a network filesystem.
4. Using the binary on the network filesystem, lldb now goes
to find the dSYM.
5. It starts by looking for a dSYM next to the binary it found.
6. lldb is now reading the dSYM over a network filesystem,
ignoring the one it found on its local filesystem earlier.
Everything still *works* but it's much slower.
This would be a tricky one to write up in a testsuite case;
you really need the binary to not exist on the local system.
And LocateMacOSXFilesUsingDebugSymbols will only compile on
Mac OS X - even if I found a way to write up a test case, it
would not run anywhere but on a mac.
One change Greg wanted while I was touching this code was to
have LocateMacOSXFilesUsingDebugSymbols (which could be asked
to find a binary OR find a dSYM) to instead return a ModuleSpec
with the sum total of everything it could find. This
change of passing around a ModuleSpec instead of a FileSpec
was percolated up into ModuleList::GetSharedModule.
The changes to LocateMacOSXFilesUsingDebugSymbols look larger
than they really are - there's a lot of simple whitespace changes
in there.
I ran the testsuites on mac, no new regressions introduced
<rdar://problem/21993813>
llvm-svn: 249755
Summary:
This doesn't exist in other LLVM projects any longer and doesn't
do anything.
Reviewers: chaoren, labath
Subscribers: emaste, tberghammer, lldb-commits, danalbert
Differential Revision: http://reviews.llvm.org/D12586
llvm-svn: 246749
This fixes a regression caused by r245645 where creating alternative
thumb disassembler was enabled even when the main disassembler is
already thumb.
llvm-svn: 246649
If no architecture is defined for the disassambler command then it uses
the architecture of the target. In case of arm it will be "arm" what is
treated as the oldest arm version by the LLVM disassambler causing a lot
of invalid opcode in the output.
This change forces the use of "armv8.1a" (the newest arm architecture) if
no sub architecure was specified (either by the user or by the target) to
disassamble all instruction.
Differential revision: http://reviews.llvm.org/D12553
llvm-svn: 246648
SUMMARY:
This patch implements Target::GetBreakableLoadAddress() method that takes an address
and checks for any reason there is a better address than this to put a breakpoint on.
If there is then return that address.
MIPS uses this method to avoid breakpoint in delay slot.
Reviewers: clayborg, jingham
Subscribers: jingham, mohit.bhakkad, sagar, jaydeep, nitesh.jain, lldb-commits
Differential Revision: http://http://reviews.llvm.org/D12184
llvm-svn: 246015
This was breaking disassembly for arm machines that we force to be
thumb mode all the time because we were only checking for llvm::Triple::arm.
i.e.
armv6m (ARM Cortex-M0)
armv7m (ARM Cortex-M3)
armv7em (ARM Cortex-M4)
<rdar://problem/22334522>
llvm-svn: 245645
SUMMARY:
The patch detects MIPS application specific extensions (ASE) like micromips by reading
ELF header.e_flags and SHT_MIPS_ABIFLAGS section. MIPS triple does not contain ASE
information like micromips, mips16, DSP, MSA etc. These can be read from header.e_flags
or SHT_MIPS_ABIFLAGS section.
Reviewers: clayborg
Subscribers: mohit.bhakkad, sagar, lldb-commits
Differential Revision: http://reviews.llvm.org/D11133
llvm-svn: 242381
Patch by Jaydeep Patil
SUMMARY:
1. Added emulation of MIPS64 floating-point branch instructions
2. Updated GetRegisterInfo to recognize floating-point registers
3. Provided CPU information while creating createMCSubtargetInfo in disassembler
4. Bug fix in emulation of JIC and JIALC
5. Correct identification of breakpoint when set in a delay slot of a branch instruction
Reviewers: clayborg
Subscribers: bhushan, mohit.bhakkad, sagar, nitesh.jain, lldb-commits.
Differential Revision: http://reviews.llvm.org/D10355
llvm-svn: 239996
changing it was in r219544 - after living on that for a few
months, I wanted to take another crack at this.
The disassembly-format setting still exists and the old format
can be user specified with a setting like
${current-pc-arrow}${addr-file-or-load}{ <${function.name-without-args}${function.concrete-only-addr-offset-no-padding}>}:
This patch was discussed in http://reviews.llvm.org/D7578
<rdar://problem/19726421>
llvm-svn: 229186
Since REG_ENHANCED is available on MacOSX, this allow the use of \d (digits) \b (word boundaries) and much more without affecting other systems.
<rdar://problem/12082562>
llvm-svn: 226704
output style can be customized. Change the built-in default to be
more similar to gdb's disassembly formatting.
The disassembly-format for a gdb-like output is
${addr-file-or-load} <${function.name-without-args}${function.concrete-only-addr-offset-no-padding}>:
The disassembly-format for the lldb style output is
{${function.initial-function}{${module.file.basename}`}{${function.name-without-args}}:\n}{${function.changed}\n{${module.file.basename}`}{${function.name-without-args}}:\n}{${current-pc-arrow} }{${addr-file-or-load}}:
The two backticks in the lldb style formatter triggers the sub-expression evaluation in
CommandInterpreter::PreprocessCommand() so you can't use that one as-is ... changing to
use ' characters instead of ` would work around that.
<rdar://problem/9885398>
llvm-svn: 219544
These changes were written by Greg Clayton, Jim Ingham, Jason Molenda.
It builds cleanly against TOT llvm with xcodebuild. I updated the
cmake files by visual inspection but did not try a build. I haven't
built these sources on any non-Mac platforms - I don't think this
patch adds any code that requires darwin, but please let me know if
I missed something.
In debugserver, MachProcess.cpp and MachTask.cpp were renamed to
MachProcess.mm and MachTask.mm as they picked up some new Objective-C
code needed to launch processes when running on iOS.
llvm-svn: 205113
Previously, an opcode set via SetOpcode32 (for example) was later
extracted via GetData() as a byte sequence in host order rather than
target order.
Review: http://llvm-reviews.chandlerc.com/D1838
llvm-svn: 196808
<rdar://problem/15314403>
This patch adds a new lldb_private::SectionLoadHistory class that tracks what shared libraries were loaded given a process stop ID. This allows us to keep a history of the sections that were loaded for a time T. Many items in history objects will rely upon the process stop ID in the future.
llvm-svn: 196557
pure virtual base class and made StackFrame a subclass of that. As
I started to build on top of that arrangement today, I found that it
wasn't working out like I intended. Instead I'll try sticking with
the single StackFrame class -- there's too much code duplication to
make a more complicated class hierarchy sensible I think.
llvm-svn: 193983
defines a protocol that all subclasses will implement. StackFrame
is currently the only subclass and the methods that Frame vends are
nearly identical to StackFrame's old methods.
Update all callers to use Frame*/Frame& instead of pointers to
StackFrames.
This is almost entirely a mechanical change that touches a lot of
the code base so I'm committing it alone. No new functionality is
added with this patch, no new subclasses of Frame exist yet.
I'll probably need to tweak some of the separation, possibly moving
some of StackFrame's methods up in to Frame, but this is a good
starting point.
<rdar://problem/15314068>
llvm-svn: 193907
- Immediates can be shown as hex (either Intel or MASM style)
- See TestSettings.py for usage examples
- Verified to cause no regressions on Linux x86_64 (Ubuntu 12.10)
Patch by Richard Mitton!
llvm-svn: 187921
<rdar://problem/13594769>
Main changes in this patch include:
- cleanup plug-in interface and use ConstStrings for plug-in names
- Modfiied the BSD Archive plug-in to be able to pick out the correct .o file when .a files contain multiple .o files with the same name by using the timestamp
- Modified SymbolFileDWARFDebugMap to properly verify the timestamp on .o files it loads to ensure we don't load updated .o files and cause problems when debugging
The plug-in interface changes:
Modified the lldb_private::PluginInterface class that all plug-ins inherit from:
Changed:
virtual const char * GetPluginName() = 0;
To:
virtual ConstString GetPluginName() = 0;
Removed:
virtual const char * GetShortPluginName() = 0;
- Fixed up all plug-in to adhere to the new interface and to return lldb_private::ConstString values for the plug-in names.
- Fixed all plug-ins to return simple names with no prefixes. Some plug-ins had prefixes and most ones didn't, so now they all don't have prefixed names, just simple names like "linux", "gdb-remote", etc.
llvm-svn: 181631
PC relative loads are missing disassembly comments when disassembled in a live process.
This issue was because some sections, like __TEXT and __DATA in libobjc.A.dylib, were being moved when they were put into the dyld shared cache. This could also affect any other system that slides sections individually.
The solution is to keep track of wether the bytes we will disassemble are from an executable file (file address), or from a live process (load address). We now do the right thing based off of this input in all cases.
llvm-svn: 178315
Calculate "can branch" using the MC API's rather than our hand-rolled regex'es.
As extra credit, allow setting the disassembly flavor for x86 based architectures to intel or att.
<rdar://problem/11319574>
<rdar://problem/9329275>
llvm-svn: 176392
- generate-vers.pl has to be called by cmake to generate the version number
- parallel builds not yet supported; dependency on clang must be explicitly specified
Tested on Linux.
- Building on Mac will require code-signing logic to be implemented.
- Building on Windows will require OS-detection logic and some selective directory inclusion
Thanks to Carlo Kok (who originally prepared these CMakefiles for Windows) and Ben Langmuir
who ported them to Linux!
llvm-svn: 175795
Major fixed to allow reading files that are over 4GB. The main problems were that the DataExtractor was using 32 bit offsets as a data cursor, and since we mmap all of our object files we could run into cases where if we had a very large core file that was over 4GB, we were running into the 4GB boundary.
So I defined a new "lldb::offset_t" which should be used for all file offsets.
After making this change, I enabled warnings for data loss and for enexpected implicit conversions temporarily and found a ton of things that I fixed.
Any functions that take an index internally, should use "size_t" for any indexes and also should return "size_t" for any sizes of collections.
llvm-svn: 173463
Make breakpoint setting by file and line much more efficient by only looking for inlined breakpoint locations if we are setting a breakpoint in anything but a source implementation file. Implementing this complex for a many reasons. Turns out that parsing compile units lazily had some issues with respect to how we need to do things with DWARF in .o files. So the fixes in the checkin for this makes these changes:
- Add a new setting called "target.inline-breakpoint-strategy" which can be set to "never", "always", or "headers". "never" will never try and set any inlined breakpoints (fastest). "always" always looks for inlined breakpoint locations (slowest, but most accurate). "headers", which is the default setting, will only look for inlined breakpoint locations if the breakpoint is set in what are consudered to be header files, which is realy defined as "not in an implementation source file".
- modify the breakpoint setting by file and line to check the current "target.inline-breakpoint-strategy" setting and act accordingly
- Modify compile units to be able to get their language and other info lazily. This allows us to create compile units from the debug map and not have to fill all of the details in, and then lazily discover this information as we go on debuggging. This is needed to avoid parsing all .o files when setting breakpoints in implementation only files (no inlines). Otherwise we would need to parse the .o file, the object file (mach-o in our case) and the symbol file (DWARF in the object file) just to see what the compile unit was.
- modify the "SymbolFileDWARFDebugMap" to subclass lldb_private::Module so that the virtual "GetObjectFile()" and "GetSymbolVendor()" functions can be intercepted when the .o file contenst are later lazilly needed. Prior to this fix, when we first instantiated the "SymbolFileDWARFDebugMap" class, we would also make modules, object files and symbol files for every .o file in the debug map because we needed to fix up the sections in the .o files with information that is in the executable debug map. Now we lazily do this in the DebugMapModule::GetObjectFile()
Cleaned up header includes a bit as well.
llvm-svn: 162860
require an AddressClass, which is useless at this
point since it already knows the distinction between
32-bit Thumb opcodes and 32-bit ARM opcodes.
llvm-svn: 161382
keep a shared pointer to their disassembler. This
is important for the LLVM-C disassembler because
it needs to lock its parent in order to disassemble
itself.
This means that every interface that returned a
Disassembler* needs to return a DisassemblerSP, so
that the instructions and any external owners share
the same reference count on the object. I changed
all clients to use this shared pointer, which also
plugged a few leaks.
<rdar://problem/12002822>
llvm-svn: 161123
Fixed the DisassemblerLLVMC disassembler to parse more efficiently instead of parsing opcodes over and over. The InstructionLLVMC class now only reads the opcode in the InstructionLLVMC::Decode function. This can be done very efficiently for ARM and architectures that have fixed opcode sizes. For x64 it still calls the disassembler to get the byte size.
Moved the lldb_private::Instruction::Dump(...) function up into the lldb_private::Instruction class and it now uses the function that gets the mnemonic, operandes and comments so that all disassembly is using the same code.
Added StreamString::FillLastLineToColumn() to allow filling a line up to a column with a character (which is used by the lldb_private::Instruction::Dump(...) function).
Modified the Opcode::GetData() fucntion to "do the right thing" for thumb instructions.
llvm-svn: 156532
Switch over to the "*-apple-macosx" for desktop and "*-apple-ios" for iOS triples.
Also make the selection process for auto selecting platforms based off of an arch much better.
llvm-svn: 156354
- Addresses with no description were given
comments, leading to useless comments like
"; , "
- Addresses weren't resolved with respect
to the correct module.
llvm-svn: 153274
them both installed with the LLVM MC version being the default. I renamed the
name of the LLVM MC disassembler plug-in to "llvm-mc" and the LLVM enhanced
disassembly plug-in to "llvm-edis" and they can both be installed for now.
To use the "llvm-edis" disassembler, you can just specify it while disassembling:
(lldb) disassemble --plugin llvm-edis --name main
(lldb) disassemble --plugin llvm-mc --name main
This will allow us to compare the output of the two disassembler and eventually
deprecate the old one when the new one is ready. But it does use the new disassembler
by default so we continue to test it on a daily basis.
llvm-svn: 153231
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
Intel disassembler usable.
Also flipped the switch: we are now exclusively
using Disassembler.h instead of
EnhancedDisassembly.h for all disassembly in
LLDB.
llvm-svn: 151306
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
which uses the Disassembler.h interface to the LLVM
disassemblers rather than the EnhancedDisassembly.h
interface. Disassembler.h is a better-maintained
API and will be stabler in the long term.
Currently the output from Disassembler.h does not
provide for symbolic disassembly in all the places
that the old disassembler did, so I have gated (and
disabled) the disassembler. It'll be easy to flip
the switch later.
In the meantime, to enable the new disassembler,
uncomment "#define USE_NEW_DISASSEMBLER" in
lldb.cpp.
llvm-svn: 150772
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
be fetched too many times and the DisassemblerLLVM was appending to strings
when the opcode, mnemonic and comment accessors were called multiple times
and if any of the strings were empty.
Also fixed the test suite failures from recent Objective C modifications.
llvm-svn: 148460
symbolication. Also improved the SBInstruction API to allow
access to the instruction opcode name, mnemonics, comment and
instruction data.
Added the ability to edit SBLineEntry objects (change the file,
line and column), and also allow SBSymbolContext objects to be
modified (set module, comp unit, function, block, line entry
or symbol).
The SymbolContext and SBSymbolContext can now generate inlined
call stack infomration for symbolication much easier using the
SymbolContext::GetParentInlinedFrameInfo(...) and
SBSymbolContext::GetParentInlinedFrameInfo(...) methods.
llvm-svn: 140518
shared pointers.
Changed the ExecutionContext over to use shared pointers for
the target, process, thread and frame since these objects can
easily go away at any time and any object that was holding onto
an ExecutionContext was running the risk of using a bad object.
Now that the shared pointers for target, process, thread and
frame are just a single pointer (they all use the instrusive
shared pointers) the execution context is much safer and still
the same size.
Made the shared pointers in the the ExecutionContext class protected
and made accessors for all of the various ways to get at the pointers,
references, and shared pointers.
llvm-svn: 140298
Sean Callanan