107 Commits

Author SHA1 Message Date
Benjamin Kramer
3bf2c8347e [lldb] Clean up #includes. NFC. 2026-01-30 11:06:45 +01:00
Aman LaChapelle
10f2611c21
[lldb] Add support for ScriptedFrame to provide values/variables. (#178575)
This patch adds plumbing to support the implementations of StackFrame::Get{*}Variable{*} on ScriptedFrame. The major pieces required are:
- A modification to ScriptedFrameInterface, so that we can actually call the python methods.
- A corresponding update to the python implementation to call the python methods.
- An implementation in ScriptedFrame that can get the variable list on construction inside ScriptedFrame::Create, and pass that list into the ScriptedFrame so it can get those values on request.

There is a major caveat, which is that if the values from the python side don't have variables attached, right now, they won't be passed into the scripted frame to be stored in the variable list. Future discussions around adding support for 'extended variables' when printing frame variables may create a reason to change the VariableListSP into a ValueObjectListSP, and generate the VariableListSP on the fly, but that should be addressed at a later time.

This patch also adds tests to the frame provider test suite to prove these changes all plumb together correctly.

Related radar: rdar://165708771
2026-01-29 21:24:17 -08:00
Jason Molenda
e4c83b7b11
[lldb][NFC] Change ObjectFile argument type (#171574)
The ObjectFile plugin interface accepts an optional DataBufferSP
argument. If the caller has the contents of the binary, it can provide
this in that DataBufferSP. The ObjectFile subclasses in their
CreateInstance methods will fill in the DataBufferSP with the actual
binary contents if it is not set.
ObjectFile base class creates an ivar DataExtractor from the
DataBufferSP passed in.

My next patch will be a caller that creates a VirtualDataExtractor with
the binary data, and needs to pass that in to the ObjectFile plugin,
instead of the bag-of-bytes DataBufferSP. It builds on the previous
patch changing ObjectFile's ivar from DataExtractor to DataExtractorSP
so I could pass in a subclass in the shared ptr. And it will be using
the VirtualDataExtractor that Jonas added in
https://github.com/llvm/llvm-project/pull/168802

No behavior is changed by the patch; we're simply moving the creation of
the DataExtractor to the caller, instead of a DataBuffer that is
immediately used to set up the ObjectFile DataExtractor. The patch is a
bit complicated because all of the ObjectFile subclasses have to
initialize their DataExtractor to pass in to the base class.

I ran the testsuite on macOS and on AArch64 Ubutnu. (btw David, I ran it
under qemu on my M4 mac with SME-no-SVE again, Ubuntu 25.10, checked
lshw(1) cpu capabilities, and qemu doesn't seem to be virtualizing the
SME, that explains why the testsuite passes)

rdar://148939795

---------

Co-authored-by: Jonas Devlieghere <jonas@devlieghere.com>
2025-12-11 10:08:56 -08:00
Med Ismail Bennani
96c733e0db
[lldb] Add support for PC-less scripted frames (#170805)
Scripted frames that materialize Python functions or other non-native
code are PC-less by design, meaning they don't have valid program
counter values. Previously, these frames would display invalid addresses
(`0xffffffffffffffff`) in backtrace output.

This patch updates `FormatEntity` to detect and suppress invalid address
display for PC-less frames, adds fallback to frame methods when symbol
context is unavailable, and modifies `StackFrame::GetSymbolContext` to
skip PC-based symbol resolution for invalid addresses.

The changes enable PC-less frames to display cleanly with proper
function names, file paths, and line numbers, and allow for source
display of foreign sources (like Python). Includes comprehensive test
coverage demonstrating frames pointing to Python source files.

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2025-12-05 23:57:54 +00:00
Med Ismail Bennani
c50802cbee
Reland "[lldb] Introduce ScriptedFrameProvider for real threads (#161870)" (#170236)
This patch re-lands #161870 with fixes to the previous test failures.

rdar://161834688

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2025-12-02 18:59:40 +00:00
Med Ismail Bennani
41a53c0a23
[lldb/Target] Add BorrowedStackFrame and make StackFrame methods virtual (#170191)
This change makes StackFrame methods virtual to enable subclass
overrides and introduces BorrowedStackFrame, a wrapper that presents an
existing StackFrame with a different frame index.

This enables creating synthetic frame views or renumbering frames
without copying the underlying frame data, which is useful for frame
manipulation scenarios.

This also adds a new borrowed-info format entity to show what was the
original frame index of the borrowed frame.

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2025-12-02 10:41:03 -08:00
Michael Buch
b7bc4a2103
Revert "[lldb] Introduce ScriptedFrameProvider for real threads" (#167662)
The new test fails on x86 and arm64 public macOS bots:
```
09:27:59  ======================================================================
09:27:59  FAIL: test_append_frames (TestScriptedFrameProvider.ScriptedFrameProviderTestCase)
09:27:59     Test that we can add frames after real stack.
09:27:59  ----------------------------------------------------------------------
09:27:59  Traceback (most recent call last):
09:27:59    File "/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/llvm-project/lldb/test/API/functionalities/scripted_frame_provider/TestScriptedFrameProvider.py", line 122, in test_append_frames
09:27:59      self.assertEqual(new_frame_count, original_frame_count + 1)
09:27:59  AssertionError: 5 != 6
09:27:59  Config=arm64-/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/lldb-build/bin/clang
09:27:59  ======================================================================
09:27:59  FAIL: test_applies_to_thread (TestScriptedFrameProvider.ScriptedFrameProviderTestCase)
09:27:59     Test that applies_to_thread filters which threads get the provider.
09:27:59  ----------------------------------------------------------------------
09:27:59  Traceback (most recent call last):
09:27:59    File "/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/llvm-project/lldb/test/API/functionalities/scripted_frame_provider/TestScriptedFrameProvider.py", line 218, in test_applies_to_thread
09:27:59      self.assertEqual(
09:27:59  AssertionError: 5 != 1 : Thread with ID 1 should have 1 synthetic frame
09:27:59  Config=arm64-/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/lldb-build/bin/clang
09:27:59  ======================================================================
09:27:59  FAIL: test_prepend_frames (TestScriptedFrameProvider.ScriptedFrameProviderTestCase)
09:27:59     Test that we can add frames before real stack.
09:27:59  ----------------------------------------------------------------------
09:27:59  Traceback (most recent call last):
09:27:59    File "/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/llvm-project/lldb/test/API/functionalities/scripted_frame_provider/TestScriptedFrameProvider.py", line 84, in test_prepend_frames
09:27:59      self.assertEqual(new_frame_count, original_frame_count + 2)
09:27:59  AssertionError: 5 != 7
09:27:59  Config=arm64-/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/lldb-build/bin/clang
09:27:59  ======================================================================
09:27:59  FAIL: test_remove_frame_provider_by_id (TestScriptedFrameProvider.ScriptedFrameProviderTestCase)
09:27:59     Test that RemoveScriptedFrameProvider removes a specific provider by ID.
09:27:59  ----------------------------------------------------------------------
09:27:59  Traceback (most recent call last):
09:27:59    File "/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/llvm-project/lldb/test/API/functionalities/scripted_frame_provider/TestScriptedFrameProvider.py", line 272, in test_remove_frame_provider_by_id
09:27:59      self.assertEqual(thread.GetNumFrames(), 3, "Should have 3 synthetic frames")
09:27:59  AssertionError: 5 != 3 : Should have 3 synthetic frames
09:27:59  Config=arm64-/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/lldb-build/bin/clang
09:27:59  ======================================================================
09:27:59  FAIL: test_replace_all_frames (TestScriptedFrameProvider.ScriptedFrameProviderTestCase)
09:27:59     Test that we can replace the entire stack.
09:27:59  ----------------------------------------------------------------------
09:27:59  Traceback (most recent call last):
09:27:59    File "/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/llvm-project/lldb/test/API/functionalities/scripted_frame_provider/TestScriptedFrameProvider.py", line 41, in test_replace_all_frames
09:27:59      self.assertEqual(thread.GetNumFrames(), 3, "Should have 3 synthetic frames")
09:27:59  AssertionError: 5 != 3 : Should have 3 synthetic frames
09:27:59  Config=arm64-/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/lldb-build/bin/clang
09:27:59  ======================================================================
09:27:59  FAIL: test_scripted_frame_objects (TestScriptedFrameProvider.ScriptedFrameProviderTestCase)
09:27:59     Test that provider can return ScriptedFrame objects.
09:27:59  ----------------------------------------------------------------------
09:27:59  Traceback (most recent call last):
09:27:59    File "/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/llvm-project/lldb/test/API/functionalities/scripted_frame_provider/TestScriptedFrameProvider.py", line 159, in test_scripted_frame_objects
09:27:59      self.assertEqual(frame0.GetFunctionName(), "custom_scripted_frame_0")
09:27:59  AssertionError: 'thread_func(int)' != 'custom_scripted_frame_0'
09:27:59  - thread_func(int)
09:27:59  + custom_scripted_frame_0
09:27:59  
09:27:59  Config=arm64-/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/lldb-build/bin/clang
09:27:59  ----------------------------------------------------------------------
09:27:59  Ran 6 tests in 14.242s
09:27:59  
09:27:59  FAILED (failures=6)
```

Reverts llvm/llvm-project#161870
2025-11-12 10:13:43 +00:00
Med Ismail Bennani
1e467e4485
[lldb] Introduce ScriptedFrameProvider for real threads (#161870)
This patch extends ScriptedFrame to work with real (non-scripted)
threads,
enabling frame providers to synthesize frames for native processes.

Previously, ScriptedFrame only worked within
ScriptedProcess/ScriptedThread
contexts. This patch decouples ScriptedFrame from ScriptedThread,
allowing
users to augment or replace stack frames in real debugging sessions for
use
cases like custom calling conventions, reconstructing corrupted frames
from
core files, or adding diagnostic frames.

Key changes:

- ScriptedFrame::Create() now accepts ThreadSP instead of requiring
ScriptedThread, extracting architecture from the target triple rather
than ScriptedProcess.arch

- Added SBTarget::RegisterScriptedFrameProvider() and
ClearScriptedFrameProvider() APIs, with Target storing a
SyntheticFrameProviderDescriptor template for new threads

- Added "target frame-provider register/clear" commands for CLI access

- Thread class gains LoadScriptedFrameProvider(),
ClearScriptedFrameProvider(),
and GetFrameProvider() methods for per-thread frame provider management

- New SyntheticStackFrameList overrides FetchFramesUpTo() to lazily
provide
frames from either the frame provider or the real stack

This enables practical use of the SyntheticFrameProvider infrastructure
in
real debugging workflows.

rdar://161834688

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2025-11-11 20:18:45 +00:00
Med Ismail Bennani
4cd17eeaeb
[lldb/Interpreter] Implement ScriptedFrameProvider{,Python}Interface (#166662)
This patch implements the base and python interface for the
ScriptedFrameProvider class.

This is necessary to call python APIs from the ScriptedFrameProvider
that will come in a follow-up.

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2025-11-06 11:54:17 -08:00
Med Ismail Bennani
84b56202fb
[lldb] Introduce ScriptedFrame affordance (#149622)
This patch introduces a new scripting affordance in lldb:
`ScriptedFrame`.

This allows user to produce mock stackframes in scripted threads and
scripted processes from a python script.

With this change, StackFrame can be synthetized from different sources:
- Either from a dictionary containing a load address, and a frame index,
  which is the legacy way.
- Or by creating a ScriptedFrame python object.

One particularity of synthezising stackframes from the ScriptedFrame
python object, is that these frame have an optional PC, meaning that
they don't have a report a valid PC and they can act as shells that just
contain static information, like the frame function name, the list of
variables or registers, etc. It can also provide a symbol context.

rdar://157260006

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2025-09-04 15:07:11 -07:00
Med Ismail Bennani
6c10ab8a3c
[lldb] Mark scripted frames as synthetic instead of artificial (#153117)
This patch changes the way frames created from scripted affordances like
Scripted Threads are displayed. Currently, they're marked artificial
which is used usually for compiler generated frames.

This patch changes that behaviour by introducing a new synthetic
StackFrame kind and moves 'artificial' to be a distinct StackFrame
attribut.

On top of making these frames less confusing, this allows us to know
when a frame was created from a scripted affordance.

rdar://155949703

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2025-09-03 15:58:14 -07:00
Pavel Labath
2c4f67794b
[lldb/cmake] Implicitly pass arguments to llvm_add_library (#142583)
If we're not touching them, we don't need to do anything special to pass
them along -- with one important caveat: due to how cmake arguments
work, the implicitly passed arguments need to be specified before
arguments that we handle.

This isn't particularly nice, but the alternative is enumerating all
arguments that can be used by llvm_add_library and the macros it calls
(it also relies on implicit passing of some arguments to
llvm_process_sources).
2025-06-04 11:33:37 +02:00
David Spickett
65b0d21eb4 [lldb] Remove "error:" prefix from reverse execute error messages
Errors will get "error:" prefixes automatically so this is not needed.
2025-04-29 14:01:01 +00:00
Pavel Labath
1b237198dc
Reapply "[lldb] Implement basic support for reverse-continue (#125242)" (again) (#128156)
This reverts commit
87b7f63a11,
reapplying

7e66cf74fb
with a small (and probably temporary)
change to generate more debug info to help with diagnosing buildbot
issues.
2025-03-17 16:06:25 +01:00
rchamala
2ff3b18554
Allow option to ignore module load errors in ScriptedProcess (#127153)
Current state in scripted process expects [all the
modules](912b154f3a/lldb/source/Plugins/Process/scripted/ScriptedProcess.cpp (L498))
passed into "get_loaded_images" to load successfully else none of them
load. Even if a module loads fine, [but has already been
appended](912b154f3a/lldb/source/Plugins/Process/scripted/ScriptedProcess.cpp (L495))
it still fails. This is restrictive and does not help our usecase.

**Usecase**: We have a parent scripted process using coredump +
tombstone.

1) Scripted process uses child elf-core process to read memory dump

2) Uses tombstones to pass thread names and modules.

We do not know whether the modules will be successfully downloaded
before creating the scripted process. We use [python module
callbacks](a57e58dbfa/lldb/source/Target/Platform.cpp (L1593))
to download a module from symbol server at LLDB load time when the
scripted process is being created. The issue is that if one of the
symbol is not found from the list specified in tombstone, none of the
modules load in scripted process. Even if we ensure symbols are present
in symbol server before creating the scripted process, if the load
address is wrong or if the module is already appended, all module loads
are skipped.

**Solution**: Pass in a custom boolean option arg for every module from
python scripted process plugin which will indicate whether to ignore the
module load error. This will provide the flexibility to user for loading
the successfully fetched modules into target while ignoring the failed
ones

---------

Co-authored-by: rchamala <rachamal@fb.com>
2025-02-23 00:51:43 -08:00
Jason Molenda
b666ac3b63
[lldb] Change lldb's breakpoint handling behavior, reland (#126988)
lldb today has two rules: When a thread stops at a BreakpointSite, we
set the thread's StopReason to be "breakpoint hit" (regardless if we've
actually hit the breakpoint, or if we've merely stopped *at* the
breakpoint instruction/point and haven't tripped it yet). And second,
when resuming a process, any thread sitting at a BreakpointSite is
silently stepped over the BreakpointSite -- because we've already
flagged the breakpoint hit when we stopped there originally.

In this patch, I change lldb to only set a thread's stop reason to
breakpoint-hit when we've actually executed the instruction/triggered
the breakpoint. When we resume, we only silently step past a
BreakpointSite that we've registered as hit. We preserve this state
across inferior function calls that the user may do while stopped, etc.

Also, when a user adds a new breakpoint at $pc while stopped, or changes
$pc to be the address of a BreakpointSite, we will silently step past
that breakpoint when the process resumes. This is purely a UX call, I
don't think there's any person who wants to set a breakpoint at $pc and
then hit it immediately on resuming.

One non-intuitive UX from this change, butt is necessary: If you're
stopped at a BreakpointSite that has not yet executed, you `stepi`, you
will hit the breakpoint and the pc will not yet advance. This thread has
not completed its stepi, and the ThreadPlanStepInstruction is still on
the stack. If you then `continue` the thread, lldb will now stop and
say, "instruction step completed", one instruction past the
BreakpointSite. You can continue a second time to resume execution.

The bugs driving this change are all from lldb dropping the real stop
reason for a thread and setting it to breakpoint-hit when that was not
the case. Jim hit one where we have an aarch64 watchpoint that triggers
one instruction before a BreakpointSite. On this arch we are notified of
the watchpoint hit after the instruction has been unrolled -- we disable
the watchpoint, instruction step, re-enable the watchpoint and collect
the new value. But now we're on a BreakpointSite so the watchpoint-hit
stop reason is lost.

Another was reported by ZequanWu in
https://discourse.llvm.org/t/lldb-unable-to-break-at-start/78282 we
attach to/launch a process with the pc at a BreakpointSite and
misbehave. Caroline Tice mentioned it is also a problem they've had with
putting a breakpoint on _dl_debug_state.

The change to each Process plugin that does execution control is that

1. If we've stopped at a BreakpointSite that has not been executed yet,
we will call Thread::SetThreadStoppedAtUnexecutedBP(pc) to record that.
When the thread resumes, if the pc is still at the same site, we will
continue, hit the breakpoint, and stop again.

2. When we've actually hit a breakpoint (enabled for this thread or
not), the Process plugin should call
Thread::SetThreadHitBreakpointSite(). When we go to resume the thread,
we will push a step-over-breakpoint ThreadPlan before resuming.

The biggest set of changes is to StopInfoMachException where we
translate a Mach Exception into a stop reason. The Mach exception codes
differ in a few places depending on the target (unambiguously), and I
didn't want to duplicate the new code for each target so I've tested
what mach exceptions we get for each action on each target, and
reorganized StopInfoMachException::CreateStopReasonWithMachException to
document these possible values, and handle them without specializing
based on the target arch.

I first landed this patch in July 2024 via
https://github.com/llvm/llvm-project/pull/96260

but the CI bots and wider testing found a number of test case failures
that needed to be updated, I reverted it. I've fixed all of those issues
in separate PRs and this change should run cleanly on all the CI bots
now.

rdar://123942164
2025-02-13 11:30:10 -08:00
Adrian Prantl
87b7f63a11 Revert "Reland "[lldb] Implement basic support for reverse-continue" (#125242)"
This reverts commit 7e66cf74fb4e6a103f923e34700a7b6f20ac2a9b.

Breaking green dragon:

https://green.lab.llvm.org/job/llvm.org/view/LLDB/job/as-lldb-cmake/19569/testReport/junit/lldb-api/functionalities_reverse-execution/TestReverseContinueWatchpoints_py/
2025-01-31 13:11:20 -08:00
David Spickett
7e66cf74fb
Reland "[lldb] Implement basic support for reverse-continue" (#125242)
This reverts commit a774de807e56c1147d4630bfec3110c11d41776e.

This is the same changes as last time, plus:
* We load the binary into the target object so that on Windows, we can
resolve the locations of the functions.
* We now assert that each required breakpoint has at least 1 location,
to prevent an issue like that in the future.
* We are less strict about the unsupported error message, because it
prints "error: windows" on Windows instead of "error: gdb-remote".
2025-01-31 15:56:33 +00:00
David Spickett
a774de807e
Revert "Reland "[lldb] Implement basic support for reverse-continue" (#123906)"" (#125091)
Reverts llvm/llvm-project#123945

Has failed on the Windows on Arm buildbot:
https://lab.llvm.org/buildbot/#/builders/141/builds/5865
```
********************
Unresolved Tests (2):
  lldb-api :: functionalities/reverse-execution/TestReverseContinueBreakpoints.py
  lldb-api :: functionalities/reverse-execution/TestReverseContinueWatchpoints.py
********************
Failed Tests (1):
  lldb-api :: functionalities/reverse-execution/TestReverseContinueNotSupported.py
```
Reverting while I reproduce locally.
2025-01-30 16:45:36 +00:00
David Spickett
0caba6c8dc
Reland "[lldb] Implement basic support for reverse-continue" (#123906)" (#123945)
This reverts commit 22561cfb443267905d4190f0e2a738e6b412457f and fixes
b7b9ccf44988edf49886743ae5c3cf4184db211f (#112079).

The problem is that x86_64 and Arm 32-bit have memory regions above the
stack that are readable but not writeable. First Arm:
```
(lldb) memory region --all
<...>
[0x00000000fffcf000-0x00000000ffff0000) rw- [stack]
[0x00000000ffff0000-0x00000000ffff1000) r-x [vectors]
[0x00000000ffff1000-0xffffffffffffffff) ---
```
Then x86_64:
```
$ cat /proc/self/maps
<...>
7ffdcd148000-7ffdcd16a000 rw-p 00000000 00:00 0                          [stack]
7ffdcd193000-7ffdcd196000 r--p 00000000 00:00 0                          [vvar]
7ffdcd196000-7ffdcd197000 r-xp 00000000 00:00 0                          [vdso]
ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0                  [vsyscall]
```
Compare this to AArch64 where the test did pass:
```
$ cat /proc/self/maps
<...>
ffffb87dc000-ffffb87dd000 r--p 00000000 00:00 0                          [vvar]
ffffb87dd000-ffffb87de000 r-xp 00000000 00:00 0                          [vdso]
ffffb87de000-ffffb87e0000 r--p 0002a000 00:3c 76927217                   /usr/lib/aarch64-linux-gnu/ld-linux-aarch64.so.1
ffffb87e0000-ffffb87e2000 rw-p 0002c000 00:3c 76927217                   /usr/lib/aarch64-linux-gnu/ld-linux-aarch64.so.1
fffff4216000-fffff4237000 rw-p 00000000 00:00 0                          [stack]
```
To solve this, look up the memory region of the stack pointer (using
https://lldb.llvm.org/resources/lldbgdbremote.html#qmemoryregioninfo-addr)
and constrain the read to within that region. Since we know the stack is
all readable and writeable.

I have also added skipIfRemote to the tests, since getting them working
in that context is too complex to be worth it.

Memory write failures now display the range they tried to write, and
register write errors will show the name of the register where possible.

The patch also includes a workaround for a an issue where the test code
could mistake an `x` response that happens to begin with an `O` for an
output packet (stdout). This workaround will not be necessary one we
start using the [new
implementation](https://discourse.llvm.org/t/rfc-fixing-incompatibilties-of-the-x-packet-w-r-t-gdb/84288)
of the `x` packet.

---------

Co-authored-by: Pavel Labath <pavel@labath.sk>
2025-01-30 14:03:01 +00:00
Pavel Labath
22561cfb44
Revert "[lldb] Implement basic support for reverse-continue" (#123906)
Reverts llvm/llvm-project#112079 due to failures on the arm bot.
2025-01-22 09:43:11 +01:00
Robert O'Callahan
b7b9ccf449
[lldb] Implement basic support for reverse-continue (#112079)
This commit adds support for a
`SBProcess::ContinueInDirection()` API. A user-accessible command for
this will follow in a later commit.

This feature depends on a gdbserver implementation (e.g. `rr`) providing
support for the `bc` and `bs` packets. `lldb-server` does not support
those packets, and there is no plan to change that. For testing
purposes, this commit adds a Python implementation of *very limited*
record-and-reverse-execute functionality, implemented as a proxy between
lldb and lldb-server in `lldbreverse.py`. This should not (and in
practice cannot) be used for anything except testing.

The tests here are quite minimal but we test that simple breakpoints and
watchpoints work as expected during reverse execution, and that
conditional breakpoints and watchpoints work when the condition calls a
function that must be executed in the forward direction.
2025-01-22 08:37:17 +01:00
Jason Molenda
3bef742559 Revert "[lldb] Implement basic support for reverse-continue (#99736)"
Reverting this again; I added a commit which added @skipIfDarwin
markers to the TestReverseContinueBreakpoints.py and
TestReverseContinueNotSupported.py API tests, which use lldb-server
in gdbserver mode which does not work on Darwin.  But the aarch64 ubuntu
bot reported a failure on TestReverseContinueBreakpoints.py,
https://lab.llvm.org/buildbot/#/builders/59/builds/6397

  File "/home/tcwg-buildbot/worker/lldb-aarch64-ubuntu/llvm-project/lldb/test/API/functionalities/reverse-execution/TestReverseContinueBreakpoints.py", line 63, in test_reverse_continue_skip_breakpoint
    self.reverse_continue_skip_breakpoint_internal(async_mode=False)
  File "/home/tcwg-buildbot/worker/lldb-aarch64-ubuntu/llvm-project/lldb/test/API/functionalities/reverse-execution/TestReverseContinueBreakpoints.py", line 81, in reverse_continue_skip_breakpoint_internal
    self.expect(
  File "/home/tcwg-buildbot/worker/lldb-aarch64-ubuntu/llvm-project/lldb/packages/Python/lldbsuite/test/lldbtest.py", line 2372, in expect
    self.runCmd(
  File "/home/tcwg-buildbot/worker/lldb-aarch64-ubuntu/llvm-project/lldb/packages/Python/lldbsuite/test/lldbtest.py", line 1002, in runCmd
    self.assertTrue(self.res.Succeeded(), msg + output)
AssertionError: False is not true : Process should be stopped due to history boundary
Error output:
error: Process must be launched.

This reverts commit 4f297566b3150097de26c6a23a987d2bd5fc19c5.
2024-10-10 16:24:38 -07:00
Robert O'Callahan
4f297566b3 [lldb] Implement basic support for reverse-continue (#99736)
This commit only adds support for the
`SBProcess::ReverseContinue()` API. A user-accessible command for this
will follow in a later commit.

This feature depends on a gdbserver implementation (e.g. `rr`) providing
support for the `bc` and `bs` packets. `lldb-server` does not support
those packets, and there is no plan to change that. So, for testing
purposes, `lldbreverse.py` wraps `lldb-server` with a Python
implementation of *very limited* record-and-replay functionality for use
by *tests only*.

The majority of this PR is test infrastructure (about 700 of the 950
lines added).
2024-10-10 16:08:19 -07:00
Augusto Noronha
2ff4c25b7e Revert "[lldb] Implement basic support for reverse-continue (#99736)"
This reverts commit d5e1de6da96c1ab3b8cae68447e8ed3696a7006e.
2024-10-10 15:05:58 -07:00
Robert O'Callahan
d5e1de6da9
[lldb] Implement basic support for reverse-continue (#99736)
This commit only adds support for the
`SBProcess::ReverseContinue()` API. A user-accessible command for this
will follow in a later commit.

This feature depends on a gdbserver implementation (e.g. `rr`) providing
support for the `bc` and `bs` packets. `lldb-server` does not support
those packets, and there is no plan to change that. So, for testing
purposes, `lldbreverse.py` wraps `lldb-server` with a Python
implementation of *very limited* record-and-replay functionality for use
by *tests only*.

The majority of this PR is test infrastructure (about 700 of the 950
lines added).
2024-10-10 13:01:47 -07:00
Adrian Prantl
0642cd768b
[lldb] Turn lldb_private::Status into a value type. (#106163)
This patch removes all of the Set.* methods from Status.

This cleanup is part of a series of patches that make it harder use the
anti-pattern of keeping a long-lives Status object around and updating
it while dropping any errors it contains on the floor.

This patch is largely NFC, the more interesting next steps this enables
is to:
1. remove Status.Clear()
2. assert that Status::operator=() never overwrites an error
3. remove Status::operator=()

Note that step (2) will bring 90% of the benefits for users, and step
(3) will dramatically clean up the error handling code in various
places. In the end my goal is to convert all APIs that are of the form

`    ResultTy DoFoo(Status& error)
`
to

`    llvm::Expected<ResultTy> DoFoo()
`
How to read this patch?

The interesting changes are in Status.h and Status.cpp, all other
changes are mostly

` perl -pi -e 's/\.SetErrorString/ = Status::FromErrorString/g' $(git
grep -l SetErrorString lldb/source)
`
plus the occasional manual cleanup.
2024-08-27 10:59:31 -07:00
Jason Molenda
52c08d7ffd Revert "[lldb] Change lldb's breakpoint handling behavior (#96260)"
This reverts commit 05f0e86cc895181b3d2210458c78938f83353002.

The debuginfo dexter tests are failing, probably because the way
stepping over breakpoints has changed with my patches.  And there
are two API tests fails on the ubuntu-arm (32-bit) bot. I'll need
to investigate both of these, neither has an obvious failure reason.
2024-07-19 18:43:53 -07:00
Jason Molenda
05f0e86cc8
[lldb] Change lldb's breakpoint handling behavior (#96260)
lldb today has two rules: When a thread stops at a BreakpointSite, we
set the thread's StopReason to be "breakpoint hit" (regardless if we've
actually hit the breakpoint, or if we've merely stopped *at* the
breakpoint instruction/point and haven't tripped it yet). And second,
when resuming a process, any thread sitting at a BreakpointSite is
silently stepped over the BreakpointSite -- because we've already
flagged the breakpoint hit when we stopped there originally.

In this patch, I change lldb to only set a thread's stop reason to
breakpoint-hit when we've actually executed the instruction/triggered
the breakpoint. When we resume, we only silently step past a
BreakpointSite that we've registered as hit. We preserve this state
across inferior function calls that the user may do while stopped, etc.

Also, when a user adds a new breakpoint at $pc while stopped, or changes
$pc to be the address of a BreakpointSite, we will silently step past
that breakpoint when the process resumes. This is purely a UX call, I
don't think there's any person who wants to set a breakpoint at $pc and
then hit it immediately on resuming.

One non-intuitive UX from this change, but I'm convinced it is
necessary: If you're stopped at a BreakpointSite that has not yet
executed, you `stepi`, you will hit the breakpoint and the pc will not
yet advance. This thread has not completed its stepi, and the thread
plan is still on the stack. If you then `continue` the thread, lldb will
now stop and say, "instruction step completed", one instruction past the
BreakpointSite. You can continue a second time to resume execution. I
discussed this with Jim, and trying to paper over this behavior will
lead to more complicated scenarios behaving non-intuitively. And mostly
it's the testsuite that was trying to instruction step past a breakpoint
and getting thrown off -- and I changed those tests to expect the new
behavior.

The bugs driving this change are all from lldb dropping the real stop
reason for a thread and setting it to breakpoint-hit when that was not
the case. Jim hit one where we have an aarch64 watchpoint that triggers
one instruction before a BreakpointSite. On this arch we are notified of
the watchpoint hit after the instruction has been unrolled -- we disable
the watchpoint, instruction step, re-enable the watchpoint and collect
the new value. But now we're on a BreakpointSite so the watchpoint-hit
stop reason is lost.

Another was reported by ZequanWu in
https://discourse.llvm.org/t/lldb-unable-to-break-at-start/78282 we
attach to/launch a process with the pc at a BreakpointSite and
misbehave. Caroline Tice mentioned it is also a problem they've had with
putting a breakpoint on _dl_debug_state.

The change to each Process plugin that does execution control is that

1. If we've stopped at a BreakpointSite that has not been executed yet,
we will call Thread::SetThreadStoppedAtUnexecutedBP(pc) to record
that.  When the thread resumes, if the pc is still at the same site, we
will continue, hit the breakpoint, and stop again.

2. When we've actually hit a breakpoint (enabled for this thread or not),
the Process plugin should call Thread::SetThreadHitBreakpointSite().
When we go to resume the thread, we will push a step-over-breakpoint
ThreadPlan before resuming.

The biggest set of changes is to StopInfoMachException where we
translate a Mach Exception into a stop reason. The Mach exception codes
differ in a few places depending on the target (unambiguously), and I
didn't want to duplicate the new code for each target so I've tested
what mach exceptions we get for each action on each target, and
reorganized StopInfoMachException::CreateStopReasonWithMachException to
document these possible values, and handle them without specializing
based on the target arch.

rdar://123942164
2024-07-19 17:26:13 -07:00
jimingham
9d3aec5535
Fix a stall in running quit while a live process is running (#74687)
We need to generate events when finalizing, or we won't know that we
succeeded in stopping the process to detach/kill. Instead, we stall and
then after our 20 interrupt timeout, we kill the process (even if we
were supposed to detach) and exit.

OTOH, we have to not generate events when the Process is being
destructed because shared_from_this has already been torn down, and
using it will cause crashes.
2023-12-07 14:36:27 -08:00
Alex Langford
133bcacecf
[lldb] Change interface of StructuredData::Array::GetItemAtIndexAsDictionary (#71961)
Similar to my previous patch (#71613) where I changed
`GetItemAtIndexAsString`, this patch makes the same change to
`GetItemAtIndexAsDictionary`.

`GetItemAtIndexAsDictionary` now returns a std::optional that is either
`std::nullopt` or is a valid pointer. Therefore, if the optional is
populated, we consider the pointer to always be valid (i.e. no need to
check pointer validity).
2023-11-10 12:47:43 -08:00
Med Ismail Bennani
0adbde6541
[lldb] Fix assert in ScriptedProcess destructor (#71744)
This patch should fix a test failure in
`Expr/TestIRMemoryMapWindows.test`:

https://lab.llvm.org/buildbot/#/builders/219/builds/6786

The problem here is that since 7991412 landed, all the
`ScriptInterpreter::CreateScripted*Interface` now return a `nullptr`
when using the base `ScriptInterpreter` instance, instead of
`ScriptInterpreterPython` for instance.

This nullptr is actually well handled in the various places where we
create a Scripted Interface, however, because of the way to instanciate
a process, the process plugin manager have to iterate over every process
plugin and call the `CreateInstance` static function that should
instanciate the right object.

So in the ScriptedProcess case, because we are getting a `nullptr` when
trying to create a `ScriptedProcessInterface`, we try to discard the
process object, which calls the Process destructor, which in turns calls
the `ScriptedProcess` plugin `IsAlive` method. That method will fire an
assertion if the scripted interface pointer is not allocated.

This patch address that issue by setting a flag when destroying the
ScriptedProcess object, and checks that flag when calling `IsAlive`.

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-11-08 17:18:40 -08:00
Med Ismail Bennani
2abf997f82 [lldb] Fix assertions caused by un-checked errors in ScriptedProcess
This patch should fix some assertion that started getting hit after f22d82c.

That commit changed the scripted object plugin creation to use
`llvm::Expected<T>` as a return type to enforce error handling, however
I forgot to handle the error which caused the assert.

The interesting  part about this, is that since that assert was triggered
in the ScriptedProcess constructor (where the `llvm::Error` wasn't
handled), that impacted every test that launched any kind of process,
since the process plugin manager would eventually also iterate over the
`ScriptedProcess::Create` factory method.

This patch should fix the assertions by handling the errors.

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-10-25 17:31:02 -07:00
Med Ismail Bennani
f22d82cef2
[lldb/Interpreter] Make ScriptedInterface Object creation more generic (#68052)
This patch changes the way plugin objects used with Scripted Interfaces
are created.

Instead of implementing a different SWIG method to create the object for
every scripted interface, this patch makes the creation more generic by
re-using some of the ScriptedPythonInterface templated Dispatch code.

This patch also improves error handling of the object creation by
returning an `llvm::Expected`.

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-10-25 10:05:54 -07:00
Med Ismail Bennani
1f5f4169c4 [lldb] Fix dead lock issue when loading modules in Scripted Process
This patch attempts to fix a dead lock when loading modules in a Scripted
Process.

This issue was triggered by loading the modules after the process did resume,
but before the process actually stop, causing the language runtime mutex to
be locked by a separate thread, responsible to unwind the stack (using
the runtime unwind plan), while the module loading thread was trying to
notify the runtimes of the newly loaded module.

To address that, this patch moves the module loading logic to be done before
sending the stop event, to prevent the dead lock situation described above.

Differential Revision: https://reviews.llvm.org/D154649

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-07-06 14:33:52 -07:00
Med Ismail Bennani
0c5b632071 [lldb] Fix failure in TestStackCoreScriptedProcess on x86_64
This patch should address the failure of TestStackCoreScriptedProcess
that is happening specifically on x86_64.

It turns out that in 1370a1cb5b97, I changed the way we extract integers
from a `StructuredData::Dictionary` and in order to get a stop info from
the scripted process, we call a method that returns a `SBStructuredData`
containing the stop reason data.

TestStackCoreScriptedProcess` was failing specifically on x86_64 because
the stop info dictionary contains the signal number, that the `Scripted
Thread` was trying to extract as a signed integer where it was actually
parsed as an unsigned integer. That caused `GetValueForKeyAsInteger` to
return the default value parameter, `LLDB_INVALID_SIGNAL_NUMBER`.

This patch address the issue by extracting the signal number with the
appropriate type and re-enables the test.

Differential Revision: https://reviews.llvm.org/D152848

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-06-21 10:57:13 -07:00
Alex Langford
35b0b24440 [lldb] Introduce DynamicRegisterInfo::CreateFromDict
I want to add some error handling to DynamicRegisterInfo because there
are many operations that can fail and many of these operations do not
give meaningful information back to the caller.

To begin that process, I want to add a static method that is responsible
for creating a DynamicRegisterInfo from a StructuredData::Dictionary
(and ArchSpec). This is meant to replace the equivalent constructor
because constructors are ill-equipped to perform error handling.

Differential Revision: https://reviews.llvm.org/D152594
2023-06-15 10:51:17 -07:00
Med Ismail Bennani
68d964d024 Revert "[lldb] Fix failure in TestStackCoreScriptedProcess on x86_64"
This reverts commit 4177b490358432a457935ba5d6d076ae60de588f, since I
landed it by mistake.
2023-06-13 13:45:59 -07:00
Med Ismail Bennani
4177b49035 [lldb] Fix failure in TestStackCoreScriptedProcess on x86_64
This patch should address the failure of TestStackCoreScriptedProcess
that is happening specifically on x86_64.

It turns out that in 1370a1cb5b97, I changed the way we extract integers
from a `StructuredData::Dictionary` and in order to get a stop info from
the scripted process, we call a method that returns a `SBStructuredData`
containing the stop reason data.

TestStackCoreScriptedProcess` was failing specifically on x86_64 because
the stop info dictionary contains the signal number, that the `Scripted
Thread` was trying to extract as a signed integer where it was actually
parsed as an unsigned integer. That caused `GetValueForKeyAsInteger` to
return the default value parameter, `LLDB_INVALID_SIGNAL_NUMBER`.

This patch address the issue by extracting the signal number with the
appropriate type and re-enables the test.

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-06-13 13:44:51 -07:00
Med Ismail Bennani
8f407b8e63 [lldb] Add "Trace" stop reason in Scripted Thread
This patch adds support to eStopReasonTrace to Scripted Threads.

This is necessary when using a Scrited Process with a Scripted Thread
Plan to report a special thread stop reason to the thread plan.

rdar://109425542

Differential Revision: https://reviews.llvm.org/D151043

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-05-22 16:14:00 -07:00
Med Ismail Bennani
1370a1cb5b [lldb] Add support for negative integer to {SB,}StructuredData
This patch refactors the `StructuredData::Integer` class to make it
templated, makes it private and adds 2 public specialization for both
`int64_t` & `uint64_t` with a public type aliases, respectively
`SignedInteger` & `UnsignedInteger`.

It adds new getter for signed and unsigned interger values to the
`StructuredData::Object` base class and changes the implementation of
`StructuredData::Array::GetItemAtIndexAsInteger` and
`StructuredData::Dictionary::GetValueForKeyAsInteger` to support signed
and unsigned integers.

This patch also adds 2 new `Get{Signed,Unsigned}IntegerValue` to the
`SBStructuredData` class and marks `GetIntegerValue` as deprecated.

Finally, this patch audits all the caller of `StructuredData::Integer`
or `StructuredData::GetIntegerValue` to use the proper type as well the
various tests that uses `SBStructuredData.GetIntegerValue`.

rdar://105575764

Differential Revision: https://reviews.llvm.org/D150485

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-05-22 16:14:00 -07:00
Med Ismail Bennani
e31d0c20e4 [lldb] Improve breakpoint management for interactive scripted process
This patch improves breakpoint management when doing interactive
scripted process debugging.

In other to know which process set a breakpoint, we need to do some book
keeping on the multiplexer scripted process. When initializing the
multiplexer, we will first copy breakpoints that are already set on the
driving target.

Everytime we launch or resume, we should copy breakpoints from the
multiplexer to the driving process.

When creating a breakpoint from a child process, it needs to be set both
on the multiplexer and on the driving process. We also tag the created
breakpoint with the name and pid of the originator process.

This patch also implements all the requirement to achieve proper
breakpoint management. That involves:

- Adding python interator for breakpoints and watchpoints in SBTarget
- Add a new `ScriptedProcess.create_breakpoint` python method

Differential Revision: https://reviews.llvm.org/D148548

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2023-04-25 15:03:15 -07:00
Med Ismail Bennani
ad03aeadfb [lldb/Plugin] Add breakpoint setting support to ScriptedProcess
This patch adds support for breakpoint setting to Scripted Processes.

For now, Scripted Processes only support setting software breakpoints.

When doing interactive scripted process debugging, it makes use of the
memory writing capability to write the trap opcodes in the memory of the
driving process. However the real process' target doesn't keep track of
the breakpoints that got added by the scripted process. This is a design
that we might need to change in the future, since we'll probably need to
do some book keeping to handle breakpoints that were set by different
scripted processes.

Differential Revision: https://reviews.llvm.org/D145296

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2023-04-25 15:02:34 -07:00
Med Ismail Bennani
6c961ae1b5 [lldb] Move ScriptedProcess private state update to implementation
While debugging a Scripted Process, in order to update its state and
work nicely with lldb's execution model, it needs to toggle its private
state from running to stopped, which will result in broadcasting a
process state changed event to the debugger listener.

Originally, this state update was done systematically in the Scripted
Process C++ plugin, however in order to make scripted process
interactive, we need to be able to update their state dynamically.

This patch makes use of the recent addition of the
SBProcess::ForceScriptedState to programatically, and moves the
process private state update to the python implementation of the resume
method instead of doing it in ScriptedProcess::DoResume.

This patch also removes the unused ShouldStop & Stop scripted
process APIs, and adds new ScriptedInterface transform methods for
boolean arguments. This allow the user to programmatically decide if
after running the process, we should stop it (which is the default setting).

Differential Revision: https://reviews.llvm.org/D145295

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2023-04-25 15:02:34 -07:00
Med Ismail Bennani
0d77e03474 [lldb/API] Introduce SBProcess::ForceScriptedState method
This patch introduces a new method to the SBProcess API called
ForceScriptedState. As the name suggests, this affordance will allow the
user to alter the state of the scripted process programatically.

This is necessary to update the scripted process state when perform
interactive debugging.

Differential Revision: https://reviews.llvm.org/D145294

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2023-04-25 15:02:33 -07:00
Med Ismail Bennani
9cbdfcdb4c [lldb] Fix assertion when ScriptedProcess have no pid after launch
This patch should fix an assertion that causes some test failures:
https://ci.swift.org/view/LLDB/job/llvm-org-lldb-release-debuginfo/3587/console

This was caused by the changes introduces in `88f409194d5a` where we
replaced `DidLaunch` by `DidResume` in the `ScriptedProcess` class.

However, by the time we resume the process, the pid should be already
set. To address this, this patch brings back `DidLaunch` which will
initialize the ScriptedProcess pid with a placeholder value. That value
will be updated in `DidResume` to the final pid.

Note, this 2 stage PID initialization is necessary sometimes, when the
scripted process gets stopped at entry (launch) and gets assigned an
object that contains the PID value. In this case, we need to update the
PID when we resume the process after we've stopped at entry.

This also replaces the default scripted process id to an arbitrary
number (42) since the current value (0) is considered invalid.

Differential Revision: https://reviews.llvm.org/D148153

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2023-04-12 16:04:22 -07:00
Jonas Devlieghere
88f409194d
[lldb] Parse the crashlog only once
Now that we can pass Python objects to the scripted process instance, we
don't need to parse the crashlog twice anymore.

Differential revision: https://reviews.llvm.org/D148063
2023-04-11 17:05:15 -07:00
David Spickett
e73dd6254e [lldb] Fix a 32 bit warning in ScriptedProcessInterface
../llvm-project/lldb/include/lldb/Interpreter/ScriptedProcessInterface.h:61:12:
warning: implicit conversion from 'unsigned long long' to 'size_t' (aka 'unsigned int')
changes value from 18446744073709551615 to 4294967295 [-Wconstant-conversion]
../llvm-project/lldb/source/Plugins/Process/scripted/ScriptedProcess.cpp:275:39:
warning: result of comparison of constant 18446744073709551615 with expression
of type 'size_t' (aka 'unsigned int') is always false [-Wtautological-constant-out-of-range-compare]

This happens because size_t on 32 bit is 32 bit, but LLDB_INVALID_OFFSET is
UINT64_MAX. Return lldb::offset_t instead, which is 64 bit everywhere.

DoWriteMemory still returns size_t but this is because every other
Process derived thing does that. As long as the failure check works I think
it should be fine.

Reviewed By: mib

Differential Revision: https://reviews.llvm.org/D146124
2023-03-21 15:34:17 +00:00
Med Ismail Bennani
896a346980 Revert "[lldb/Plugin] Add breakpoint setting support to ScriptedProcesses."
This reverts commit cfe06f495beb520ab366957d1108bb80c7c92832.
2023-03-06 13:17:45 -08:00
Med Ismail Bennani
20dbb29a1a Revert "[lldb] Move ScriptedProcess private state update to implementation"
This reverts commit 3c33d72e7fa83beb8a9b39fb3b8ecf4ee00c697d.
2023-03-06 13:17:43 -08:00