summaryrefslogtreecommitdiff
path: root/lldb/source/Target/StackFrameList.cpp
AgeCommit message (Collapse)Author
2025-11-12Revert "[lldb] Introduce ScriptedFrameProvider for real threads" (#167662)Michael Buch
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
2025-11-11[lldb] Introduce ScriptedFrameProvider for real threads (#161870)Med Ismail Bennani
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>
2025-09-12[lldb] Track CFA pointer metadata in StackID (#157498)Felipe de Azevedo Piovezan
[lldb] Track CFA pointer metadata in StackID In this commit: 9c8e71644227 [lldb] Make StackID call Fix{Code,Data} pointers (#152796) We made StackID keep track of the CFA without any pointer metadata in it. This is necessary when comparing two StackIDs to determine which one is "younger". However, the CFA inside StackIDs is also used in other contexts through the method StackID::GetCallFrameAddress. One notable case is DWARFExpression: the computation of `DW_OP_call_frame_address` is done using StackID. This feeds into many other places, e.g. expression evaluation may require the address of a variable that is computed from the CFA; to access the variable without faulting, we may need to preserve the pointer metadata. As such, StackID must be able to provide both versions of the CFA. In the spirit of allowing consumers of pointers to decide what to do with pointer metadata, this patch changes StackID to store both versions of the cfa pointer. Two getter methods are provided, and all call sites except DWARFExpression preserve their existing behavior (stripped pointer). Other alternatives were considered: * Just store the raw pointer. This would require changing the comparisong operator `<` to also receive a Process, as the comparison requires stripped pointers. It wasn't clear if all call-sites had a non-null process, whereas we know we have a process when creating a StackID. * Store a weak pointer to the process inside the class, and then strip metadata as needed. This would require a `weak_ptr::lock` in many operations of LLDB, and it felt wasteful. It also prevents stripping of the pointer if the process has gone away. This patch also changes RegisterContextUnwind::ReadFrameAddress, which is the method computing the CFA fed into StackID, to also preserve the signature pointers.
2025-09-08[lldb][Target] Clear selected frame index after a StopInfo::PerformAction ↵Michael Buch
(#133078) The motivation for this patch is that `StopInfo::GetSuggestedStackFrameIndex` would not take effect for `InstrumentationRuntimeStopInfo` (which we plan to implement in https://github.com/llvm/llvm-project/pull/133079). This was happening because the instrumentation runtime plugins would run utility expressions as part of the stop that would set the `m_selected_frame_idx`. This means `SelectMostRelevantFrame` was never called, and we would not be able to report the selected frame via the `StopInfo` object. This patch makes sure we clear the `m_selected_frame_idx` to allow `GetSuggestedStackFrameIndex` to take effect, regardless of what the frame recognizers choose to do.
2025-09-03[lldb] Mark scripted frames as synthetic instead of artificial (#153117)Med Ismail Bennani
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>
2025-07-25[lldb] Protect the selected frame idx in StackFrameList (#150718)Jonas Devlieghere
Protected m_selected_frame_idx with a mutex. To avoid deadlocks, always acquire m_selected_frame_mutex after m_list_mutex. I'm using a recursive mutex because GetSelectedFrameIndex may indirectly call SetSelectedFrame.
2025-07-11When running OS Plugins from dSYM's, make sure start state is correct (#146441)jimingham
This is an odd corner case of the use of scripts loaded from dSYM's - a macOS only feature, which can load OS Plugins that re-present the thread state of the program we attach to. If we find out about and load the dSYM scripts when we discover a target in the course of attaching to it, we can end up running the OS plugin before we've started up the private state thread. However, the os_plugin in that case will be running before we broadcast the stop event to the public event listener. So it should formally use the private state and not the public state for the Python code environment. This patch says that if we have not yet started up the private state thread, then any thread that is servicing events is doing so on behalf of the private state machinery, and should see the private state, not the public state. Most of the patch is getting a test that will actually reproduce the error. Only the test `test_python_os_plugin_remote` actually reproduced the error. In `test_python_os_plugin` we actually do start up the private state thread before handling the event. `test_python_os_plugin` is there for completeness sake.
2024-12-12Convert the StackFrameList mutex to a shared mutex. (#117252)jimingham
In fact, there's only one public API in StackFrameList that changes the list explicitly. The rest only change the list if you happen to ask for more frames than lldb has currently fetched and that always adds frames "behind the user's back". So we were much more prone to deadlocking than we needed to be. This patch uses a shared_mutex instead, and when we have to add more frames (in GetFramesUpTo) we switches to exclusive long enough to add the frames, then goes back to shared. Most of the work here was actually getting the stack frame list locking to not require a recursive mutex (shared mutexes aren't recursive). I also added a test that has 5 threads progressively asking for more frames simultaneously to make sure we get back valid frames and don't deadlock.
2024-10-30Fix call site breakpoint patch (#114158)jimingham
This fixes the two test suite failures that I missed in the PR: https://github.com/llvm/llvm-project/pull/112939 One was a poorly written test case - it assumed that on connect to a gdb-remote with a running process, lldb MUST have fetched all the frame 0 registers. In fact, there's no need for it to do so (as the CallSite patch showed...) and if we don't need to we shouldn't. So I fixed the test to only expect a `g` packet AFTER calling read_registers. The other was a place where some code had used 0 when it meant LLDB_INVALID_LINE_NUMBER, which I had fixed but missed one place where it was still compared to 0.
2024-10-28Revert "Add the ability to break on call-site locations, improve inli… ↵jimingham
(#113947) …ne stepping (#112939)" This was breaking some gdb-remote packet counting tests on the bots. I can't see how this patch could cause that breakage, but I'm reverting to figure that out. This reverts commit f14743794587db102c6d1b20f9c87a1ac20decfd.
2024-10-28Add the ability to break on call-site locations, improve inline stepping ↵jimingham
(#112939) Previously lldb didn't support setting breakpoints on call site locations. This patch adds that ability. It would be very slow if we did this by searching all the debug information for every inlined subroutine record looking for a call-site match, so I added one restriction to the call-site support. This change will find all call sites for functions that also supply at least one line to the regular line table. That way we can use the fact that the line table search will move the location to that subsequent line (but only within the same function). When we find an actually moved source line match, we can search in the function that contained that line table entry for the call-site, and set the breakpoint location back to that. When I started writing tests for this new ability, it quickly became obvious that our support for virtual inline stepping was pretty buggy. We didn't print the right file & line number for the breakpoint, and we didn't set the position in the "virtual inlined stack" correctly when we hit the breakpoint. We also didn't step through the inlined frames correctly. There was code to try to detect the right inlined stack position, but it had been refactored a while back with the comment that it was super confusing and the refactor was supposed to make it clearer, but the refactor didn't work either. That code was made much clearer by abstracting the job of "handling the stack readjustment" to the various StopInfo's. Previously, there was a big (and buggy) switch over stop info's. Moving the responsibility to the stop info made this code much easier to reason about. We also had no tests for virtual inlined stepping (our inlined stepping test was actually written specifically to avoid the formation of a virtual inlined stack... So I also added tests for that along with the tests for setting the call-site breakpoints.
2024-08-30[lldb] Deal with SupportFiles in SourceManager (NFC) (#106740)Jonas Devlieghere
To support detecting MD5 checksum mismatches, deal with SupportFiles rather than a plain FileSpecs in the SourceManager.
2024-08-23Revert "Revert "[lldb] Extend frame recognizers to hide frames from ↵Adrian Prantl
backtraces (#104523)"" This reverts commit 547917aebd1e79a8929b53f0ddf3b5185ee4df74.
2024-08-22Revert "[lldb] Extend frame recognizers to hide frames from backtraces ↵Dmitri Gribenko
(#104523)" This reverts commit f01f80ce6ca7640bb0e267b84b1ed0e89b57e2d9. This commit introduces an msan violation. See the discussion on https://github.com/llvm/llvm-project/pull/104523.
2024-08-20[lldb] Extend frame recognizers to hide frames from backtraces (#104523)Adrian Prantl
Compilers and language runtimes often use helper functions that are fundamentally uninteresting when debugging anything but the compiler/runtime itself. This patch introduces a user-extensible mechanism that allows for these frames to be hidden from backtraces and automatically skipped over when navigating the stack with `up` and `down`. This does not affect the numbering of frames, so `f <N>` will still provide access to the hidden frames. The `bt` output will also print a hint that frames have been hidden. My primary motivation for this feature is to hide thunks in the Swift programming language, but I'm including an example recognizer for `std::function::operator()` that I wished for myself many times while debugging LLDB. rdar://126629381 Example output. (Yes, my proof-of-concept recognizer could hide even more frames if we had a method that returned the function name without the return type or I used something that isn't based off regex, but it's really only meant as an example). before: ``` (lldb) thread backtrace --filtered=false * thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1 * frame #0: 0x0000000100001f04 a.out`foo(x=1, y=1) at main.cpp:4:10 frame #1: 0x0000000100003a00 a.out`decltype(std::declval<int (*&)(int, int)>()(std::declval<int>(), std::declval<int>())) std::__1::__invoke[abi:se200000]<int (*&)(int, int), int, int>(__f=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:149:25 frame #2: 0x000000010000399c a.out`int std::__1::__invoke_void_return_wrapper<int, false>::__call[abi:se200000]<int (*&)(int, int), int, int>(__args=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:216:12 frame #3: 0x0000000100003968 a.out`std::__1::__function::__alloc_func<int (*)(int, int), std::__1::allocator<int (*)(int, int)>, int (int, int)>::operator()[abi:se200000](this=0x000000016fdff280, __arg=0x000000016fdff224, __arg=0x000000016fdff220) at function.h:171:12 frame #4: 0x00000001000026bc a.out`std::__1::__function::__func<int (*)(int, int), std::__1::allocator<int (*)(int, int)>, int (int, int)>::operator()(this=0x000000016fdff278, __arg=0x000000016fdff224, __arg=0x000000016fdff220) at function.h:313:10 frame #5: 0x0000000100003c38 a.out`std::__1::__function::__value_func<int (int, int)>::operator()[abi:se200000](this=0x000000016fdff278, __args=0x000000016fdff224, __args=0x000000016fdff220) const at function.h:430:12 frame #6: 0x0000000100002038 a.out`std::__1::function<int (int, int)>::operator()(this= Function = foo(int, int) , __arg=1, __arg=1) const at function.h:989:10 frame #7: 0x0000000100001f64 a.out`main(argc=1, argv=0x000000016fdff4f8) at main.cpp:9:10 frame #8: 0x0000000183cdf154 dyld`start + 2476 (lldb) ``` after ``` (lldb) bt * thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1 * frame #0: 0x0000000100001f04 a.out`foo(x=1, y=1) at main.cpp:4:10 frame #1: 0x0000000100003a00 a.out`decltype(std::declval<int (*&)(int, int)>()(std::declval<int>(), std::declval<int>())) std::__1::__invoke[abi:se200000]<int (*&)(int, int), int, int>(__f=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:149:25 frame #2: 0x000000010000399c a.out`int std::__1::__invoke_void_return_wrapper<int, false>::__call[abi:se200000]<int (*&)(int, int), int, int>(__args=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:216:12 frame #6: 0x0000000100002038 a.out`std::__1::function<int (int, int)>::operator()(this= Function = foo(int, int) , __arg=1, __arg=1) const at function.h:989:10 frame #7: 0x0000000100001f64 a.out`main(argc=1, argv=0x000000016fdff4f8) at main.cpp:9:10 frame #8: 0x0000000183cdf154 dyld`start + 2476 Note: Some frames were hidden by frame recognizers ```
2024-07-09[lldb] Correct invalid format style (#98089)Alex Langford
Fixes https://github.com/llvm/llvm-project/issues/97511
2024-03-21[lldb] Reland: Store SupportFile in FileEntry (NFC) (#85892)Jonas Devlieghere
This is another step towards supporting DWARF5 checksums and inline source code in LLDB. This is a reland of #85468 but without the functional change of storing the support file from the line table (yet).
2024-03-19Revert "[lldb] Store SupportFile in FileEntry (NFC)" (#85885)Jonas Devlieghere
Reverts llvm/llvm-project#85468 because @slackito reports this broke stepping in one of their tests [1] and this patch was meant to be NFC. [1] https://github.com/llvm/llvm-project/commit/d5a277d309e92b1d3e493da6036cffdf815105b1#commitcomment-139991120
2024-03-15[lldb] Store SupportFile in FileEntry (NFC) (#85468)Jonas Devlieghere
This is another step towards supporting DWARF5 checksums and inline source code in LLDB.
2023-11-30[lldb] [mostly NFC] Large WP foundation: WatchpointResources (#68845)Jason Molenda
This patch is rearranging code a bit to add WatchpointResources to Process. A WatchpointResource is meant to represent a hardware watchpoint register in the inferior process. It has an address, a size, a type, and a list of Watchpoints that are using this WatchpointResource. This current patch doesn't add any of the features of WatchpointResources that make them interesting -- a user asking to watch a 24 byte object could watch this with three 8 byte WatchpointResources. Or a Watchpoint on 1 byte at 0x1002 and a second watchpoint on 1 byte at 0x1003, these must both be served by a single WatchpointResource on that doubleword at 0x1000 on a 64-bit target, if two hardware watchpoint registers were used to track these separately, one of them may not be hit. Or if you have one Watchpoint on a variable with a condition set, and another Watchpoint on that same variable with a command defined or different condition, or ignorecount, both of those Watchpoints need to evaluate their criteria/commands when their WatchpointResource has been hit. There's a bit of code movement to rearrange things in the direction I'll need for implementing this feature, so I want to start with reviewing & landing this mostly NFC patch and we can focus on the algorithmic choices about how WatchpointResources are shared and handled as they're triggeed, separately. This patch also stops printing "Watchpoint <n> hit: old value: <x>, new vlaue: <y>" for Read watchpoints. I could make an argument for print "Watchpoint <n> hit: current value <x>" but the current output doesn't make any sense, and the user can print the value if they are particularly interested. Read watchpoints are used primarily to understand what code is reading a variable. This patch adds more fallbacks for how to print the objects being watched if we have types, instead of assuming they are all integral values, so a struct will print its elements. As large watchpoints are added, we'll be doing a lot more of those. To track the WatchpointSP in the WatchpointResources, I changed the internal API which took a WatchpointSP and devolved it to a Watchpoint*, which meant touching several different Process files. I removed the watchpoint code in ProcessKDP which only reported that watchpoints aren't supported, the base class does that already. I haven't yet changed how we receive a watchpoint to identify the WatchpointResource responsible for the trigger, and identify all Watchpoints that are using this Resource to evaluate their conditions etc. This is the same work that a BreakpointSite needs to do when it has been tiggered, where multiple Breakpoints may be at the same address. There is not yet any printing of the Resources that a Watchpoint is implemented in terms of ("watchpoint list", or SBWatchpoint::GetDescription). "watchpoint set var" and "watchpoint set expression" take a size argument which was previously 1, 2, 4, or 8 (an enum). I've changed this to an unsigned int. Most hardware implementations can only watch 1, 2, 4, 8 byte ranges, but with Resources we'll allow a user to ask for different sized watchpoints and set them in hardware-expressble terms soon. I've annotated areas where I know there is work still needed with LWP_TODO that I'll be working on once this is landed. I've tested this on aarch64 macOS, aarch64 Linux, and Intel macOS. https://discourse.llvm.org/t/rfc-large-watchpoint-support-in-lldb/72116 (cherry picked from commit fc6b72523f3d73b921690a713e97a433c96066c6)
2023-11-28Revert "[lldb] [mostly NFC] Large WP foundation: WatchpointResources (#68845)"David Spickett
...and follow ups. As it has caused test failures on Linux Arm and AArch64: https://lab.llvm.org/buildbot/#/builders/96/builds/49126 https://lab.llvm.org/buildbot/#/builders/17/builds/45824 ``` lldb-shell :: Subprocess/clone-follow-child-wp.test lldb-shell :: Subprocess/fork-follow-child-wp.test lldb-shell :: Subprocess/vfork-follow-child-wp.test ``` This reverts commit a6c62bf1a4717accc852463b664cd1012237d334, commit a0a1ff3ab40e347589b4e27d8fd350c600526735 and commit fc6b72523f3d73b921690a713e97a433c96066c6.
2023-11-27[lldb] [mostly NFC] Large WP foundation: WatchpointResources (#68845)Jason Molenda
This patch is rearranging code a bit to add WatchpointResources to Process. A WatchpointResource is meant to represent a hardware watchpoint register in the inferior process. It has an address, a size, a type, and a list of Watchpoints that are using this WatchpointResource. This current patch doesn't add any of the features of WatchpointResources that make them interesting -- a user asking to watch a 24 byte object could watch this with three 8 byte WatchpointResources. Or a Watchpoint on 1 byte at 0x1002 and a second watchpoint on 1 byte at 0x1003, these must both be served by a single WatchpointResource on that doubleword at 0x1000 on a 64-bit target, if two hardware watchpoint registers were used to track these separately, one of them may not be hit. Or if you have one Watchpoint on a variable with a condition set, and another Watchpoint on that same variable with a command defined or different condition, or ignorecount, both of those Watchpoints need to evaluate their criteria/commands when their WatchpointResource has been hit. There's a bit of code movement to rearrange things in the direction I'll need for implementing this feature, so I want to start with reviewing & landing this mostly NFC patch and we can focus on the algorithmic choices about how WatchpointResources are shared and handled as they're triggeed, separately. This patch also stops printing "Watchpoint <n> hit: old value: <x>, new vlaue: <y>" for Read watchpoints. I could make an argument for print "Watchpoint <n> hit: current value <x>" but the current output doesn't make any sense, and the user can print the value if they are particularly interested. Read watchpoints are used primarily to understand what code is reading a variable. This patch adds more fallbacks for how to print the objects being watched if we have types, instead of assuming they are all integral values, so a struct will print its elements. As large watchpoints are added, we'll be doing a lot more of those. To track the WatchpointSP in the WatchpointResources, I changed the internal API which took a WatchpointSP and devolved it to a Watchpoint*, which meant touching several different Process files. I removed the watchpoint code in ProcessKDP which only reported that watchpoints aren't supported, the base class does that already. I haven't yet changed how we receive a watchpoint to identify the WatchpointResource responsible for the trigger, and identify all Watchpoints that are using this Resource to evaluate their conditions etc. This is the same work that a BreakpointSite needs to do when it has been tiggered, where multiple Breakpoints may be at the same address. There is not yet any printing of the Resources that a Watchpoint is implemented in terms of ("watchpoint list", or SBWatchpoint::GetDescription). "watchpoint set var" and "watchpoint set expression" take a size argument which was previously 1, 2, 4, or 8 (an enum). I've changed this to an unsigned int. Most hardware implementations can only watch 1, 2, 4, 8 byte ranges, but with Resources we'll allow a user to ask for different sized watchpoints and set them in hardware-expressble terms soon. I've annotated areas where I know there is work still needed with LWP_TODO that I'll be working on once this is landed. I've tested this on aarch64 macOS, aarch64 Linux, and Intel macOS. https://discourse.llvm.org/t/rfc-large-watchpoint-support-in-lldb/72116
2023-08-09[lldb] Sink StreamFile into lldbHostAlex Langford
StreamFile subclasses Stream (from lldbUtility) and is backed by a File (from lldbHost). It does not depend on anything from lldbCore or any of its sibling libraries, so I think it makes sense for this to live in lldbHost instead. Differential Revision: https://reviews.llvm.org/D157460
2023-07-06Refine the reporting mechanism for interruption.Jim Ingham
Also, make it possible for new Targets which haven't been added to the TargetList yet to check for interruption, and add a few more places in building modules where we can check for interruption. Differential Revision: https://reviews.llvm.org/D154542
2023-05-11We can't let GetStackFrameCount get interrupted or it will give theJim Ingham
wrong answer. Plus, it's useful in some places to have a way to force the full stack to be created even in the face of interruption. Moreover, most of the time when you're just getting frames, you don't need to know the number of frames in the stack to start with. You just keep calling Thread::GetStackFrameAtIndex(index++) and when you get a null StackFrameSP back, you're done. That's also more amenable to interruption if you are doing some work frame by frame. So this patch makes GetStackFrameCount always return the full count, suspending interruption. I also went through all the places that use GetStackFrameCount to make sure that they really needed the full stack walk. In many cases, they did not. For instance frame select -r 10 was getting the number of frames just to check whether cur_frame_idx + 10 was within the stack. It's better in that case to see if that frame exists first, since that doesn't force a full stack walk, and only deal with walking off the end of the stack if it doesn't... I also added a test for some of these behaviors. Differential Revision: https://reviews.llvm.org/D150236
2023-04-21Make sure SelectMostRelevantFrame happens only when returning to the user.Jim Ingham
This is a user facing action, it is meant to focus the user's attention on something other than the 0th frame when you stop somewhere where that's helpful. For instance, stopping in pthread_kill after an assert will select the assert frame. This is not something you want to have happen internally in lldb, both because internally you really don't want the selected frame changing out from under you, and because the recognizers can do arbitrary work, and that can cause deadlocks or other unexpected behavior. However, it's not something that the current code does explicitly after a stop has been delivered, it's expected to happen implicitly as part of stopping. I changing this to call SMRF explicitly after a user stop, but that got pretty ugly quickly. So I added a bool to control whether to run this and audited all the current uses to determine whether we're returning to the user or not. Differential Revision: https://reviews.llvm.org/D148863
2023-04-07[lldb] Move "SelectMostRelevantFrame" from Thread::WillStopJim Ingham
SelectMostRelevantFrame triggers the StackFrameRecognizer construction, which can run arbitrary Python code, call expressions etc. WillStop gets called on every private stop while the recognizers are a user-facing feature, so first off doing this work on every stop is inefficient. But more importantly, you can get in to situations where the recognizer causes an expression to get run, then when we fetch the stop event at the end of the expression evaluation, we call WillStop again on the expression handling thread, which will do the same StackFrameRecognizer work again. If anyone is locking along that path, you will end up with a deadlock between the two threads. The example that brought this to my attention was the objc_exception_throw recognizer which can cause the objc runtime introspection functions to get run, and those take a lock in AppleObjCRuntimeV2::DynamicClassInfoExtractor::UpdateISAToDescriptorMap along this path, so the second thread servicing the expression deadlocks against the first thread waiting for the expression to complete. It makes more sense to have the frame recognizers run on demand, either when someone asks for the variables for the frame, or when someone does GetSelectedFrame. The former already worked that way, the only reason this was being done in WillStop was because the StackFrameRecognizers can change the SelectedFrame, so you needed to run them before the anyone requested the SelectedFrame. This patch moves SelectMostRelevantFrame to StackFrameList, and runs it when GetSelectedFrame is called for the first time on a given stop. If you call SetSelectedFrame before GetSelectedFrame, then you should NOT run the recognizer & change the frame out from under you. This patch also makes that work. There were already tests for this behavior, and for the feature that caused the hang, but the hang is racy, and it doesn't trigger all the time, so I don't have a way to test that explicitly. One more detail: it's actually pretty easy to end up calling GetSelectedFrame, for instance if you ask for the best ExecutionContext from an ExecutionContextRef it will fill the StackFrame with the result of GetSelectedFrame and that would still have the same problems if this happens on the Private State Thread. So this patch also short-circuits SelectMostRelevantFrame if run on the that thread. I can't think of any reason the computations that go on on the Private State Thread would actually want the SelectedFrame - that's a user-facing concept, so avoiding that complication is the best way to go. rdar://107643231 Differential revision: https://reviews.llvm.org/D147753
2023-03-15Add a Debugger interruption mechanism in conjunction with theJim Ingham
Command Interpreter mechanism. Differential Revision: https://reviews.llvm.org/D145136
2022-08-08[lldb] LLVM_FALLTHROUGH => [[fallthrough]]. NFCFangrui Song
2022-02-03[lldb] Rename Logging.h to LLDBLog.h and clean up includesPavel Labath
Most of our code was including Log.h even though that is not where the "lldb" log channel is defined (Log.h defines the generic logging infrastructure). This worked because Log.h included Logging.h, even though it should. After the recent refactor, it became impossible the two files include each other in this direction (the opposite inclusion is needed), so this patch removes the workaround that was put in place and cleans up all files to include the right thing. It also renames the file to LLDBLog to better reflect its purpose.
2022-02-02[lldb] Convert "LLDB" log channel to the new APIPavel Labath
2021-04-24[lldb] [gdb-remote server] Introduce new stop reasons for fork and vforkMichał Górny
Introduce three new stop reasons for fork, vfork and vforkdone events. This includes server support for serializing fork/vfork events into gdb-remote protocol. The stop infos for the two base events take a pair of PID and TID for the newly forked process. Differential Revision: https://reviews.llvm.org/D100196
2021-04-12[lldb] Delete dead StackFrameList::MergeRaphael Isemann
That code is unused since it's check-in in 2010 (and I believe it would leak memory when called as it releases the passed unique_ptr), so let's delete it. Reviewed By: vsk Differential Revision: https://reviews.llvm.org/D100212
2021-03-03LanguageRuntime for 0th frame unwind, simplify getting pc-for-symbolicationJason Molenda
Add calls into LanguageRuntime when finding the unwind method to use out of the 0th (currently executing) stack frame. Allow for the LanguageRuntimes to indicate if this stack frames should be treated like a zeroth-frame -- symbolication should be done based on the saved pc address, not decremented like normal ABI function calls. Add methods to RegisterContext and StackFrame to get a pc value suitable for symbolication, to reduce the number of places in lldb where we decrement the saved pc values before symbolication. <rdar://problem/70398009> Differential Revision: https://reviews.llvm.org/D97644
2020-06-09[lldb] Fix -Wmissing-field-initializers in StackFrameListPavel Labath
The code is correct without these default values, but it is freaking the compiler out.
2020-06-08[lldb/DWARF] Fix PC value for artificial tail call frames for the "GNU" casePavel Labath
Summary: The way that the support for the GNU dialect of tail call frames was implemented in D80519 meant that the were reporting very bogus PC values which pointed into the middle of an instruction: the -1 trick is necessary for the address to resolve to the right function, but we should still be reporting a more realistic PC value -- I say "realistic" and not "real", because it's very debatable what should be the correct PC value for frames like this. This patch achieves that my moving the -1 from SymbolFileDWARF into the stack frame computation code. The idea is that SymbolFileDWARF will merely report whether it has provided an address of the instruction after the tail call, or the address of the call instruction itself. The StackFrameList machinery uses this information to set the "behaves like frame zero" property of the artificial frames (the main thing this flag does is it controls the -1 subtraction when looking up the function address). This required a moderate refactor of the CallEdge class, because it was implicitly assuming that edges pointing after the call were real calls and those pointing the the call insn were tail calls. The class now carries this information explicitly -- it carries three mostly independent pieces of information: - an address of interest in the caller - a bit saying whether this address points to the call insn or after it - whether this is a tail call Reviewers: vsk, dblaikie Subscribers: aprantl, mgrang, lldb-commits Tags: #lldb Differential Revision: https://reviews.llvm.org/D81010
2020-03-24[lldb/DWARF] Reland: Use DW_AT_call_pc to determine artificial frame addressVedant Kumar
Reland with changes: the test modified in this change originally failed on a Debian/x86_64 builder, and I suspect the cause was that lldb looked up the line location for an artificial frame by subtracting 1 from the frame's address. For artificial frames, the subtraction must not happen because the address is already exact. --- lldb currently guesses the address to use when creating an artificial frame (i.e., a frame constructed by determining the sequence of (tail) calls which must have happened). Guessing the address creates problems -- use the actual address provided by the DW_AT_call_pc attribute instead. Depends on D76336. rdar://60307600 Differential Revision: https://reviews.llvm.org/D76337
2020-03-24Revert "[lldb/DWARF] Use DW_AT_call_pc to determine artificial frame address"Vedant Kumar
This reverts commit 6905394d153960ded3a7b884a9747ed2d4a6e8d8. The changed test is failing on Debian/x86_64, possibly because lldb is subtracting an offset from the DW_AT_call_pc address used for the artificial frame: http://lab.llvm.org:8011/builders/lldb-x86_64-debian/builds/7171/steps/test/logs/stdio /home/worker/lldb-x86_64-debian/lldb-x86_64-debian/llvm-project/lldb/test/API/functionalities/tail_call_frames/unambiguous_sequence/main.cpp:6:17: error: CHECK-NEXT: expected string not found in input // CHECK-NEXT: frame #1: 0x{{[0-9a-f]+}} a.out`func3() at main.cpp:14:3 [opt] [artificial] ^ <stdin>:3:2: note: scanning from here frame #1: 0x0000000000401127 a.out`func3() at main.cpp:13:4 [opt] [artificial]
2020-03-24[lldb/DWARF] Use DW_AT_call_pc to determine artificial frame addressVedant Kumar
lldb currently guesses the address to use when creating an artificial frame (i.e., a frame constructed by determining the sequence of (tail) calls which must have happened). Guessing the address creates problems -- use the actual address provided by the DW_AT_call_pc attribute instead. Depends on D76336. rdar://60307600 Differential Revision: https://reviews.llvm.org/D76337
2020-03-09[lldb] Return Unwinder& from Thread::GetUnwinderPavel Labath
The function always returns a valid object. Let the return type reflect that, and remove some null checks.
2020-02-04[lldb/StackFrameList] Convert assert to defensive check in ↵Vedant Kumar
SynthesizeTailCallFrames In order to synthesize tail call frames, the stack frame list must not be empty (otherwise, there is no "previous" frame to infer a tail call from). This case is hard to hit. To trigger it, we must first fail to push `unwind_frame_sp` because we either fail to get its SymbolContext, or given its SymbolContext the GetParentOfInlineScope call fails. This causes m_concrete_frames_fetched to be incremented while m_frames remains empty. Then, the next frame in the stack may fail within SynthesizeTailCallFrames. This crash arose during a kernel debugging session. rdar://59147051
2020-01-24[lldb][NFC] Fix all formatting errors in .cpp file headersRaphael Isemann
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
2019-11-22[DWARF] Handle call sites with indirect call targetsVedant Kumar
Split CallEdge into DirectCallEdge and IndirectCallEdge. Teach DWARFExpression how to evaluate entry values in cases where the current activation was created by an indirect call. rdar://57094085 Differential Revision: https://reviews.llvm.org/D70100
2019-09-30[StackFrameList][DFS] Turn a few raw pointers into references, NFCVedant Kumar
llvm-svn: 373267
2019-09-10[Function] Factor out GetCallEdgeForReturnAddress, NFCVedant Kumar
Finding the call edge in a function which corresponds to a particular return address is a generic/useful operation. llvm-svn: 371543
2019-08-02Fix PC adjustment in StackFrame::GetSymbolContextJoseph Tremoulet
Summary: Update StackFrame::GetSymbolContext to mirror the logic in RegisterContextLLDB::InitializeNonZerothFrame that knows not to do the pc decrement when the given frame is a signal trap handler frame or the parent of one, because the pc may not follow a call in these frames. Accomplish this by adding a behaves_like_zeroth_frame field to lldb_private::StackFrame, set to true for the zeroth frame, for signal handler frames, and for parents of signal handler frames. Also add logic to propagate the signal handler flag from UnwindPlan to the FrameType on the RegisterContextLLDB it generates, and factor out a helper to resolve symbol and address range for an Address now that we need to invoke it in four places. Reviewers: jasonmolenda, clayborg, jfb Reviewed By: jasonmolenda Subscribers: labath, dexonsmith, lldb-commits Tags: #lldb Differential Revision: https://reviews.llvm.org/D64993 llvm-svn: 367691
2019-07-24[Logging] Replace Log::Printf with LLDB_LOG macro (NFC)Jonas Devlieghere
This patch replaces explicit calls to log::Printf with the new LLDB_LOGF macro. The macro is similar to LLDB_LOG but supports printf-style format strings, instead of formatv-style format strings. So instead of writing: if (log) log->Printf("%s\n", str); You'd write: LLDB_LOG(log, "%s\n", str); This change was done mechanically with the command below. I replaced the spurious if-checks with vim, since I know how to do multi-line replacements with it. find . -type f -name '*.cpp' -exec \ sed -i '' -E 's/log->Printf\(/LLDB_LOGF\(log, /g' "{}" + Differential revision: https://reviews.llvm.org/D65128 llvm-svn: 366936
2019-04-10[NFC] Remove ASCII lines from commentsJonas Devlieghere
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
2019-02-13Replace 'ap' with 'up' suffix in variable names. (NFC)Jonas Devlieghere
The `ap` suffix is a remnant of lldb's former use of auto pointers, before they got deprecated. Although all their uses were replaced by unique pointers, some variables still carried the suffix. In r353795 I removed another auto_ptr remnant, namely redundant calls to ::get for unique_pointers. Jim justly noted that this is a good opportunity to clean up the variable names as well. I went over all the changes to ensure my find-and-replace didn't have any undesired side-effects. I hope I didn't miss any, but if you end up at this commit doing a git blame on a weirdly named variable, please know that the change was unintentional. llvm-svn: 353912
2019-02-11Use std::make_shared in LLDB (NFC)Jonas Devlieghere
Unlike std::make_unique, which is only available since C++14, std::make_shared is available since C++11. Not only is std::make_shared a lot more readable compared to ::reset(new), it also performs a single heap allocation for the object and control block. Differential revision: https://reviews.llvm.org/D57990 llvm-svn: 353764