Copying from the inline documentation:
```
Trace exporter plug-ins operate on traces, converting the trace data provided by an \a lldb_private::TraceCursor into a different format that can be digested by other tools, e.g. Chrome Trace Event Profiler.
Trace exporters are supposed to operate on an architecture-agnostic fashion, as a TraceCursor, which feeds the data, hides the actual trace technology being used.
```
I want to use this to make the code in https://reviews.llvm.org/D105741 a plug-in. I also imagine that there will be more and more exporters being implemented, as an exporter creates something useful out of trace data. And tbh I don't want to keep adding more stuff to the lldb/Target folder.
This is the minimal definition for a TraceExporter plugin. I plan to use this with the following commands:
- thread trace export <plug-in name> [plug-in specific args]
- This command would support autocompletion of plug-in names
- thread trace export list
- This command would list the available trace exporter plug-ins
I don't plan to create yet a "process trace export" because it's easier to start analyzing the trace of a given thread than of the entire process. When we need a process-level command, we can implement it.
I also don't plan to force each "export" command implementation to support multiple threads (for example, "thread trace start 1 2 3" or "thread trace start all" operate on many threads simultaneously). The reason is that the format used by the exporter might or might not support multiple threads, so I'm leaving this decision to each trace exporter plug-in.
Differential Revision: https://reviews.llvm.org/D106501
When the user types that command 'thread trace dump info' and there's a running Trace session in LLDB, a raw trace in bytes should be printed; the command 'thread trace dump info all' should print the info for all the threads.
Original Author: hanbingwang
Reviewed By: clayborg, wallace
Differential Revision: https://reviews.llvm.org/D105717
D104422 added the interface for TraceCursor, which is the main way to traverse instructions in a trace. This diff implements the corresponding cursor class for Intel PT and deletes the now obsolete code.
Besides that, the logic for the "thread trace dump instructions" was adapted to use this cursor (pretty much I ended up moving code from Trace.cpp to TraceCursor.cpp). The command by default traverses the instructions backwards, and if the user passes --forwards, then it's not forwards. More information about that is in the Options.td file.
Regarding the Intel PT cursor. All Intel PT cursors for the same thread share the same DecodedThread instance. I'm not yet implementing lazy decoding because we don't need it. That'll be for later. For the time being, the entire thread trace is decoded when the first cursor for that thread is requested.
Differential Revision: https://reviews.llvm.org/D105531
Replacing existing uses with AppendError.
SetError is also part of the SBI API. This remains
but instead of calling the underlying SetError it
will call AppendError.
Reviewed By: teemperor
Differential Revision: https://reviews.llvm.org/D104768
This adds a basic SB API for creating and stopping traces.
Note: This doesn't add any APIs for inspecting individual instructions. That'd be a more complicated change and it might be better to enhande the dump functionality to output the data in binary format. I'll leave that for a later diff.
This also enhances the existing tests so that they test the same flow using both the command interface and the SB API.
I also did some cleanup of legacy code.
Differential Revision: https://reviews.llvm.org/D103500
This is part 2, covering the commands source.
Some uses remain where it's tricky to see what the
logic is or they are not used with AppendError.
Reviewed By: teemperor
Differential Revision: https://reviews.llvm.org/D104448
This converts a default constructor's member initializers into C++11
default member initializers. This patch was automatically generated with
clang-tidy and the modernize-use-default-member-init check.
$ run-clang-tidy.py -header-filter='lldb' -checks='-*,modernize-use-default-member-init' -fix
This is a mass-refactoring patch and this commit will be added to
.git-blame-ignore-revs.
Differential revision: https://reviews.llvm.org/D103483
This implements the interactive trace start and stop methods.
This diff ended up being much larger than I anticipated because, by doing it, I found that I had implemented in the beginning many things in a non optimal way. In any case, the code is much better now.
There's a lot of boilerplate code due to the gdb-remote protocol, but the main changes are:
- New tracing packets: jLLDBTraceStop, jLLDBTraceStart, jLLDBTraceGetBinaryData. The gdb-remote packet definitions are quite comprehensive.
- Implementation of the "process trace start|stop" and "thread trace start|stop" commands.
- Implementaiton of an API in Trace.h to interact with live traces.
- Created an IntelPTDecoder for live threads, that use the debugger's stop id as checkpoint for its internal cache.
- Added a functionality to stop the process in case "process tracing" is enabled and a new thread can't traced.
- Added tests
I have some ideas to unify the code paths for post mortem and live threads, but I'll do that in another diff.
Differential Revision: https://reviews.llvm.org/D91679
Depends on D90490.
The stop command is simple and invokes the new method Trace::StopTracingThread(thread).
On the other hand, the start command works by delegating its implementation to a CommandObject provided by the Trace plugin. This is necessary because each trace plugin needs different options for this command. There's even the chance that a Trace plugin can't support live tracing, but instead supports offline decoding and analysis, which means that "thread trace dump instructions" works but "thread trace start" doest. Because of this and a few other reasons, it's better to have each plugin provide this implementation.
Besides, I'm using the GetSupportedTraceType method introduced in D90490 to quickly infer what's the trace plug-in that works for the current process.
As an implementation note, I moved CommandObjectIterateOverThreads to its header so that I can use it from the IntelPT plugin. Besides, the actual start and stop logic for intel-pt is not part of this diff.
Reviewed By: clayborg
Differential Revision: https://reviews.llvm.org/D90729
Depends on D89408.
This diff finally implements trace decoding!
The current interface is
$ trace load /path/to/trace/session/file.json
$ thread trace dump instructions
thread #1: tid = 3842849, total instructions = 22
[ 0] 0x40052d
[ 1] 0x40052d
...
[19] 0x400521
$ # simply enter, which is a repeat command
[20] 0x40052d
[21] 0x400529
...
This doesn't do any disassembly, which will be done in the next diff.
Changes:
- Added an IntelPTDecoder class, that is a wrapper for libipt, which is the actual library that performs the decoding.
- Added TraceThreadDecoder class that decodes traces and memoizes the result to avoid repeating the decoding step.
- Added a DecodedThread class, which represents the output from decoding and that for the time being only stores the list of reconstructed instructions. Later it'll contain the function call hierarchy, which will enable reconstructing backtraces.
- Added basic APIs for accessing the trace in Trace.h:
- GetInstructionCount, which counts the number of instructions traced for a given thread
- IsTraceFailed, which returns an Error if decoding a thread failed
- ForEachInstruction, which iterates on the instructions traced for a given thread, concealing the internal storage of threads, as plug-ins can decide to generate the instructions on the fly or to store them all in a vector, like I do.
- DumpTraceInstructions was updated to print the instructions or show an error message if decoding was impossible.
- Tests included
Differential Revision: https://reviews.llvm.org/D89283
Depends on D88841
As per the discussion in the RFC, we'll implement both
thread trace dump [instructions | functions]
This is the first step in implementing the "instructions" dumping command.
It includes:
- A minimal ProcessTrace plugin for representing processes from a trace file. I noticed that it was a required step to mimic how core-based processes are initialized, e.g. ProcessElfCore and ProcessMinidump. I haven't had the need to create ThreadTrace yet, though. So far HistoryThread seems good enough.
- The command handling itself in CommandObjectThread, which outputs a placeholder text instead of the actual instructions. I'll do that part in the next diff.
- Tests
{F13132325}
Differential Revision: https://reviews.llvm.org/D88769
1. Added a common completion completing with a list of the threads of the current process;
2. Apply the common completion above to these commands: thread
continue/info/exception/select/step-in/step-inst/step-inst-over/step-out/step-over/step-script
3. Correlated test case test_common_completion_thread_index.
Reviewed By: teemperor
Differential Revision: https://reviews.llvm.org/D84088
Dedicated completion for the command `thread plan discard` with a corresponding
test case.
Reviewed By: teemperor
Differential Revision: https://reviews.llvm.org/D83234
Summary:
This replaces the current use of LLDB's own `StringConvert` with LLVM's
`to_integer` which has a less error-prone API and doesn't use special 'error
values' to designate parsing problems.
Where needed I also added missing error handling code that prints a parsing
error instead of continuing with the error value returned from `StringConvert`
(which either gave a cryptic error message or just took the error value
performed an incorrect action with it. For example, `frame recognizer delete -1`
just deleted the frame recognizer at index 0).
Reviewers: #lldb, labath
Reviewed By: labath
Subscribers: labath, abidh, JDevlieghere
Differential Revision: https://reviews.llvm.org/D82297
that were not reported by the OS plugin. To facilitate this, move
adding/updating the ThreadPlans for a Thread to the ThreadPlanStackMap.
Also move dumping thread plans there as well.
Added some tests for "thread plan list" and "thread plan discard" since
I didn't seem to have written any originally.
Differential Revision: https://reviews.llvm.org/D76814
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
Summary:
A *.cpp file header in LLDB (and in LLDB) should like this:
```
//===-- TestUtilities.cpp -------------------------------------------------===//
```
However in LLDB most of our source files have arbitrary changes to this format and
these changes are spreading through LLDB as folks usually just use the existing
source files as templates for their new files (most notably the unnecessary
editor language indicator `-*- C++ -*-` is spreading and in every review
someone is pointing out that this is wrong, resulting in people pointing out that this
is done in the same way in other files).
This patch removes most of these inconsistencies including the editor language indicators,
all the different missing/additional '-' characters, files that center the file name, missing
trailing `===//` (mostly caused by clang-format breaking the line).
Reviewers: aprantl, espindola, jfb, shafik, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: dexonsmith, wuzish, emaste, sdardis, nemanjai, kbarton, MaskRay, atanasyan, arphaman, jfb, abidh, jsji, JDevlieghere, usaxena95, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D73258
Summary: This removes most of unnecessary includes in the `source/Commands` directory. This was generated by IWYU and a script that fixed all the bogus reports from IWYU. Patch is tested on Linux and macOS.
Reviewers: JDevlieghere
Reviewed By: JDevlieghere
Subscribers: krytarowski, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D71489
Summary:
CompileUnit is a complicated class. Having it be implicitly convertible
to a FileSpec makes reasoning about it even harder.
This patch replaces the inheritance by a simple member and an accessor
function. This avoid the need for casting in places where one needed to
force a CompileUnit to be treated as a FileSpec, and does not add much
verbosity elsewhere.
It also fixes a bug where we were wrongly comparing CompileUnit& and a
CompileUnit*, which compiled due to a combination of this inheritance
and the FileSpec*->FileSpec implicit constructor.
Reviewers: teemperor, JDevlieghere, jdoerfert
Subscribers: lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D70827
For example, it is pretty easy to write a breakpoint command that implements "stop when my caller is Foo", and
it is pretty easy to write a breakpoint command that implements "stop when my caller is Bar". But there's no
way to write a generic "stop when my caller is..." function, and then specify the caller when you add the
command to a breakpoint.
With this patch, you can pass this data in a SBStructuredData dictionary. That will get stored in
the PythonCommandBaton for the breakpoint, and passed to the implementation function (if it has the right
signature) when the breakpoint is hit. Then in lldb, you can say:
(lldb) break com add -F caller_is -k caller_name -v Foo
More generally this will allow us to write reusable Python breakpoint commands.
Differential Revision: https://reviews.llvm.org/D68671
This will allow us to write reusable scripted ThreadPlans, since
you can use key/value pairs with known keys in the plan to parametrize
its behavior.
Differential Revision: https://reviews.llvm.org/D68366
llvm-svn: 373675
The StringRef should always be identical to the C string, so we
might as well just create the StringRef from the C-string. This
might be slightly slower until we implement the storage of ArgEntry
with a string instead of a std::unique_ptr<char[]>. Until then we
have to do the additional strlen on the C string to construct the
StringRef.
llvm-svn: 371842
Summary:
We currently have several CommandObjects that manually reimplement the checking for a selected target
or a target in the execution context (which is the selected target when they are invoked). This patch removes
all these checks and replaces them by setting the eCommandRequiresTarget flag that Pavel suggested. With
this flag we are doing the same check but without having to duplicate this code in all these CommandObjects.
I also added a `GetSelectedTarget()` variant of the `GetSelectedOrDummyTarget()` function to the
CommandObject that checks that the flag is set and then returns a reference to the target. I didn't rewrite
all the `target` variables from `Target *` to `Target &` in this patch as last time this change caused a lot of merge
conflicts in Swift and I would prefer having that in a separate NFC commit.
Reviewers: labath, clayborg
Reviewed By: labath, clayborg
Subscribers: clayborg, JDevlieghere, jingham, amccarth, abidh, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D66863
llvm-svn: 370571
Summary:
We currently have a bunch of code that is supposed to handle invalid command options, but
all this code is unreachable because invalid options are already handled in `Options::Parse`.
The only way we can reach this code is when we declare but then not implement an option
(which will be made impossible with D65386, which is also when we can completely remove
the `default` cases).
This patch replaces all this code with `llvm_unreachable` to make clear this is dead code
that can't be reached.
Reviewers: JDevlieghere
Reviewed By: JDevlieghere
Subscribers: lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D66522
llvm-svn: 369625
Summary:
Right now our CommandOptions.inc only generates the initializer for the options list but
not the array declaration boilerplate around it. As the array definition is identical for all arrays,
we might as well also let the CommandOptions.inc generate it alongside the initializers.
This patch will also allow us to generate additional declarations related to that option list in
the future (e.g. a enum class representing the specific options which would make our
handling code less prone).
This patch also fixes a few option tables that didn't follow our naming style.
Reviewers: JDevlieghere
Reviewed By: JDevlieghere
Subscribers: abidh, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D65331
llvm-svn: 367186
Beside turning the options into the new tablegen format, this patch
also fixes that a few commands had source file completions for the
"count" and "end-linenumber" arguments (which both accepted only
integers). Reason for that are that somehow we added a '1' instead
of our usual '0' value to the initial value for completion.
llvm-svn: 366425
You can only find out about this useful customization by browsing
the settings list output or the llvm.org web pages. Mention it
in the help for thread list, thread backtrace & _regex_bt commands
to make it more discoverable.
llvm-svn: 359752
In r359354 a GetDebugger() method was added to the CommandObject class,
so that we didn't have to go through the command interpreter to obtain
the script interpreter. This patch simplifies other call sites where
m_interpreter.GetDebugger() was used, and replaces them with a shorter
call to the new method.
llvm-svn: 359373
This is part two of the change started in r359330. This patch moves the
ownership of the script interpreter from the command interpreter into
the debugger. I would've preferred to remove the lazy initialization,
however the fact that the scripting language is set after the debugger
is created makes that tricky. So for now this does exactly the same
thing as when it was under the command interpreter. The result is that
this patch is fully NFC.
Differential revision: https://reviews.llvm.org/D61211
llvm-svn: 359354
A lot of comments in LLDB are surrounded by an ASCII line to delimit the
begging and end of the comment.
Its use is not really consistent across the code base, sometimes the
lines are longer, sometimes they are shorter and sometimes they are
omitted. Furthermore, it looks kind of weird with the 80 column limit,
where the comment actually extends past the line, but not by much.
Furthermore, when /// is used for Doxygen comments, it looks
particularly odd. And when // is used, it incorrectly gives the
impression that it's actually a Doxygen comment.
I assume these lines were added to improve distinguishing between
comments and code. However, given that todays editors and IDEs do a
great job at highlighting comments, I think it's worth to drop this for
the sake of consistency. The alternative is fixing all the
inconsistencies, which would create a lot more churn.
Differential revision: https://reviews.llvm.org/D60508
llvm-svn: 358135
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
This builds on https://reviews.llvm.org/D43884 and https://reviews.llvm.org/D43886 and extends LLDB support of Obj-C exceptions to also look for a "current exception" for a thread in the C++ exception handling runtime metadata (via call to __cxa_current_exception_type). We also construct an actual historical SBThread/ThreadSP that contains frames from the backtrace in the Obj-C exception object.
The high level goal this achieves is that when we're already crashed (because an unhandled exception occurred), we can still access the exception object and retrieve the backtrace from the throw point. In Obj-C, this is particularly useful because a catch+rethrow is very common and in those cases you currently don't have any access to the throw point backtrace.
Differential Revision: https://reviews.llvm.org/D44072
llvm-svn: 349718
This adds new APIs and a command to deal with exceptions (mostly Obj-C exceptions): SBThread and Thread get GetCurrentException API, which returns an SBValue/ValueObjectSP with the current exception for a thread. "Current" means an exception that is currently being thrown, caught or otherwise processed. In this patch, we only know about the exception when in objc_exception_throw, but subsequent patches will expand this (and add GetCurrentExceptionBacktrace, which will return an SBThread/ThreadSP containing a historical thread backtrace retrieved from the exception object. Currently unimplemented, subsequent patches will implement this).
Extracting the exception from objc_exception_throw is implemented by adding a frame recognizer.
This also add a new sub-command "thread exception", which prints the current exception.
Differential Revision: https://reviews.llvm.org/D43886
llvm-svn: 347813
When debugging read-only memory we cannot use software breakpoint. We
already have support for hardware breakpoints and users can specify them
with `-H`. However, there's no option to force LLDB to use hardware
breakpoints internally, for example while stepping.
This patch adds a setting target.require-hardware-breakpoint that forces
LLDB to always use hardware breakpoints. Because hardware breakpoints
are a limited resource and can fail to resolve, this patch also extends
error handling in thread plans, where breakpoints are used for stepping.
Differential revision: https://reviews.llvm.org/D54221
llvm-svn: 346920
This patch removes the comments grouping header includes. They were
added after running IWYU over the LLDB codebase. However they add little
value, are often outdates and burdensome to maintain.
llvm-svn: 346626
This patch removes the logic for resolving paths out of FileSpec and
updates call sites to rely on the FileSystem class instead.
Differential revision: https://reviews.llvm.org/D53915
llvm-svn: 345890
These three classes have no external dependencies, but they are used
from various low-level APIs. Moving them down to Utility improves
overall code layering (although it still does not break any particular
dependency completely).
The XCode project will need to be updated after this change.
Differential Revision: https://reviews.llvm.org/D49740
llvm-svn: 339127
Summary:
This patch gets rid of the C-string parameter in the RawCommandObject::DoExecute function,
making the code simpler and less memory unsafe.
There seems to be a assumption in some command objects that this parameter could be a nullptr,
but from what I can see the rest of the API doesn't actually allow this (and other command
objects and related code pieces dereference this parameter without any checks).
Especially CommandObjectRegexCommand has error handling code for a nullptr that is now gone.
Reviewers: davide, jingham, teemperor
Reviewed By: teemperor
Subscribers: jingham, lldb-commits
Differential Revision: https://reviews.llvm.org/D49207
llvm-svn: 336955
Summary:
The comments on this class were out of date with the implementation, and
the implementation itself was inconsistent with our usage of the Timeout
class (I started converting everything to use this class back in D27136,
but I missed this one). I avoid duplicating the waiting logic by
introducing a templated WaitFor function, and make other functions
delegate to that. This function can be also used as a replacement for
the unused WaitForBitToBeSet functions I removed, if it turns out to be
necessary.
As this changes the meaning of a "zero" timeout, I tracked down all the
callers of these functions and updated them accordingly. Propagating the
changes to all the callers of RunShellCommand was a bit too much for
this patch, so I stopped there and will continue that in a follow-up
patch.
I also add some basic unittests for the functions I modified.
Reviewers: jingham, clayborg
Subscribers: mgorny, lldb-commits
Differential Revision: https://reviews.llvm.org/D46580
llvm-svn: 331880
This is intended as a clean up after the big clang-format commit
(r280751), which unfortunately resulted in many of the comment
paragraphs in LLDB being very hard to read.
FYI, the script I used was:
import textwrap
import commands
import os
import sys
import re
tmp = "%s.tmp"%sys.argv[1]
out = open(tmp, "w+")
with open(sys.argv[1], "r") as f:
header = ""
text = ""
comment = re.compile(r'^( *//) ([^ ].*)$')
special = re.compile(r'^((([A-Z]+[: ])|([0-9]+ )).*)|(.*;)$')
for line in f:
match = comment.match(line)
if match and not special.match(match.group(2)):
# skip intentionally short comments.
if not text and len(match.group(2)) < 40:
out.write(line)
continue
if text:
text += " " + match.group(2)
else:
header = match.group(1)
text = match.group(2)
continue
if text:
filled = textwrap.wrap(text, width=(78-len(header)),
break_long_words=False)
for l in filled:
out.write(header+" "+l+'\n')
text = ""
out.write(line)
os.rename(tmp, sys.argv[1])
Differential Revision: https://reviews.llvm.org/D46144
llvm-svn: 331197
