From bca507387ae1945137214ec7fb80b709927ee6e8 Mon Sep 17 00:00:00 2001 From: Michael Buch Date: Thu, 19 Sep 2024 10:06:28 +0100 Subject: [PATCH] [lldb][FrameRecognizer] Display the first non-std frame on verbose_trap (#108825) This attempts to improve user-experience when LLDB stops on a verbose_trap. Currently if a `__builtin_verbose_trap` triggers, we display the first frame above the call to the verbose_trap. So in the newly added test case, we would've previously stopped here: ``` (lldb) run Process 28095 launched: '/Users/michaelbuch/a.out' (arm64) Process 28095 stopped * thread #1, queue = 'com.apple.main-thread', stop reason = Bounds error: out-of-bounds access frame #1: 0x0000000100003f5c a.out`std::__1::vector::operator[](this=0x000000016fdfebef size=0, (null)=10) at verbose_trap.cpp:6:9 3 template 4 struct vector { 5 void operator[](unsigned) { -> 6 __builtin_verbose_trap("Bounds error", "out-of-bounds access"); 7 } 8 }; ``` After this patch, we would stop in the first non-`std` frame: ``` (lldb) run Process 27843 launched: '/Users/michaelbuch/a.out' (arm64) Process 27843 stopped * thread #1, queue = 'com.apple.main-thread', stop reason = Bounds error: out-of-bounds access frame #2: 0x0000000100003f44 a.out`g() at verbose_trap.cpp:14:5 11 12 void g() { 13 std::vector v; -> 14 v[10]; 15 } 16 ``` rdar://134490328 --- .../Target/VerboseTrapFrameRecognizer.cpp | 35 ++++++++++++++++++- ...verbose_trap-in-stl-callback-user-leaf.cpp | 22 ++++++++++++ .../Inputs/verbose_trap-in-stl-callback.cpp | 22 ++++++++++++ .../Inputs/verbose_trap-in-stl-max-depth.cpp | 13 +++++++ .../Inputs/verbose_trap-in-stl-nested.cpp | 21 +++++++++++ .../Recognizer/Inputs/verbose_trap-in-stl.cpp | 17 +++++++++ ...erbose_trap-in-stl-callback-user-leaf.test | 22 ++++++++++++ .../verbose_trap-in-stl-callback.test | 21 +++++++++++ .../verbose_trap-in-stl-max-depth.test | 16 +++++++++ .../verbose_trap-in-stl-nested.test | 13 +++++++ .../Shell/Recognizer/verbose_trap-in-stl.test | 13 +++++++ 11 files changed, 214 insertions(+), 1 deletion(-) create mode 100644 lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-callback-user-leaf.cpp create mode 100644 lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-callback.cpp create mode 100644 lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-max-depth.cpp create mode 100644 lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-nested.cpp create mode 100644 lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl.cpp create mode 100644 lldb/test/Shell/Recognizer/verbose_trap-in-stl-callback-user-leaf.test create mode 100644 lldb/test/Shell/Recognizer/verbose_trap-in-stl-callback.test create mode 100644 lldb/test/Shell/Recognizer/verbose_trap-in-stl-max-depth.test create mode 100644 lldb/test/Shell/Recognizer/verbose_trap-in-stl-nested.test create mode 100644 lldb/test/Shell/Recognizer/verbose_trap-in-stl.test diff --git a/lldb/source/Target/VerboseTrapFrameRecognizer.cpp b/lldb/source/Target/VerboseTrapFrameRecognizer.cpp index de710fcda54064..03ab58b8c59a9b 100644 --- a/lldb/source/Target/VerboseTrapFrameRecognizer.cpp +++ b/lldb/source/Target/VerboseTrapFrameRecognizer.cpp @@ -16,6 +16,39 @@ using namespace llvm; using namespace lldb; using namespace lldb_private; +/// The 0th frame is the artificial inline frame generated to store +/// the verbose_trap message. So, starting with the current parent frame, +/// find the first frame that's not inside of the STL. +static StackFrameSP FindMostRelevantFrame(Thread &selected_thread) { + // Defensive upper-bound of when we stop walking up the frames in + // case we somehow ended up looking at an infinite recursion. + const size_t max_stack_depth = 128; + + // Start at parent frame. + size_t stack_idx = 1; + StackFrameSP most_relevant_frame_sp = + selected_thread.GetStackFrameAtIndex(stack_idx); + + while (most_relevant_frame_sp && stack_idx <= max_stack_depth) { + auto const &sc = + most_relevant_frame_sp->GetSymbolContext(eSymbolContextEverything); + ConstString frame_name = sc.GetFunctionName(); + if (!frame_name) + return nullptr; + + // Found a frame outside of the `std` namespace. That's the + // first frame in user-code that ended up triggering the + // verbose_trap. Hence that's the one we want to display. + if (!frame_name.GetStringRef().starts_with("std::")) + return most_relevant_frame_sp; + + ++stack_idx; + most_relevant_frame_sp = selected_thread.GetStackFrameAtIndex(stack_idx); + } + + return nullptr; +} + VerboseTrapRecognizedStackFrame::VerboseTrapRecognizedStackFrame( StackFrameSP most_relevant_frame_sp, std::string stop_desc) : m_most_relevant_frame(most_relevant_frame_sp) { @@ -30,7 +63,7 @@ VerboseTrapFrameRecognizer::RecognizeFrame(lldb::StackFrameSP frame_sp) { ThreadSP thread_sp = frame_sp->GetThread(); ProcessSP process_sp = thread_sp->GetProcess(); - StackFrameSP most_relevant_frame_sp = thread_sp->GetStackFrameAtIndex(1); + StackFrameSP most_relevant_frame_sp = FindMostRelevantFrame(*thread_sp); if (!most_relevant_frame_sp) { Log *log = GetLog(LLDBLog::Unwind); diff --git a/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-callback-user-leaf.cpp b/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-callback-user-leaf.cpp new file mode 100644 index 00000000000000..6c36682626a6ef --- /dev/null +++ b/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-callback-user-leaf.cpp @@ -0,0 +1,22 @@ +void definitely_aborts() { __builtin_verbose_trap("User", "Invariant violated"); } + +namespace std { +void aborts_soon() { definitely_aborts(); } +} // namespace std + +void g() { std::aborts_soon(); } + +namespace std { +namespace detail { +void eventually_aborts() { g(); } +} // namespace detail + +inline namespace __1 { +void eventually_aborts() { detail::eventually_aborts(); } +} // namespace __1 +} // namespace std + +int main() { + std::eventually_aborts(); + return 0; +} diff --git a/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-callback.cpp b/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-callback.cpp new file mode 100644 index 00000000000000..23beed4c62c3b3 --- /dev/null +++ b/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-callback.cpp @@ -0,0 +1,22 @@ +namespace std { +void definitely_aborts() { __builtin_verbose_trap("Failed", "Invariant violated"); } + +void aborts_soon() { definitely_aborts(); } +} // namespace std + +void g() { std::aborts_soon(); } + +namespace std { +namespace detail { +void eventually_aborts() { g(); } +} // namespace detail + +inline namespace __1 { +void eventually_aborts() { detail::eventually_aborts(); } +} // namespace __1 +} // namespace std + +int main() { + std::eventually_aborts(); + return 0; +} diff --git a/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-max-depth.cpp b/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-max-depth.cpp new file mode 100644 index 00000000000000..48f564ce674e4d --- /dev/null +++ b/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-max-depth.cpp @@ -0,0 +1,13 @@ +namespace std { +void recursively_aborts(int depth) { + if (depth == 0) + __builtin_verbose_trap("Error", "max depth"); + + recursively_aborts(--depth); +} +} // namespace std + +int main() { + std::recursively_aborts(256); + return 0; +} diff --git a/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-nested.cpp b/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-nested.cpp new file mode 100644 index 00000000000000..67fa65c9ceae22 --- /dev/null +++ b/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl-nested.cpp @@ -0,0 +1,21 @@ +namespace std { +namespace detail { +void function_that_aborts() { __builtin_verbose_trap("Bounds error", "out-of-bounds access"); } +} // namespace detail + +inline namespace __1 { +template struct vector { + void operator[](unsigned) { detail::function_that_aborts(); } +}; +} // namespace __1 +} // namespace std + +void g() { + std::vector v; + v[10]; +} + +int main() { + g(); + return 0; +} diff --git a/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl.cpp b/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl.cpp new file mode 100644 index 00000000000000..4f01827944e166 --- /dev/null +++ b/lldb/test/Shell/Recognizer/Inputs/verbose_trap-in-stl.cpp @@ -0,0 +1,17 @@ +namespace std { +inline namespace __1 { +template struct vector { + void operator[](unsigned) { __builtin_verbose_trap("Bounds error", "out-of-bounds access"); } +}; +} // namespace __1 +} // namespace std + +void g() { + std::vector v; + v[10]; +} + +int main() { + g(); + return 0; +} diff --git a/lldb/test/Shell/Recognizer/verbose_trap-in-stl-callback-user-leaf.test b/lldb/test/Shell/Recognizer/verbose_trap-in-stl-callback-user-leaf.test new file mode 100644 index 00000000000000..5a84c163453ccd --- /dev/null +++ b/lldb/test/Shell/Recognizer/verbose_trap-in-stl-callback-user-leaf.test @@ -0,0 +1,22 @@ +# Tests that we show the first non-STL frame when +# a verbose_trap triggers from within the STL. +# +# Specifically tests that we correctly handle backtraces +# of the form: +# #0 __builtin_verbose_trap +# #1 user-code +# #2 STL +# #3 user-code +# #4 STL +# #5 user-code + +# UNSUPPORTED: system-windows +# +# RUN: %clang_host -g -O0 %S/Inputs/verbose_trap-in-stl-callback-user-leaf.cpp -o %t.out +# RUN: %lldb -b -s %s %t.out | FileCheck %s --check-prefixes=CHECK + +run +# CHECK: thread #{{.*}}stop reason = User: Invariant violated +frame info +# CHECK: frame #{{.*}}`definitely_aborts() at verbose_trap-in-stl-callback-user-leaf.cpp +q diff --git a/lldb/test/Shell/Recognizer/verbose_trap-in-stl-callback.test b/lldb/test/Shell/Recognizer/verbose_trap-in-stl-callback.test new file mode 100644 index 00000000000000..b15bcb3a384f98 --- /dev/null +++ b/lldb/test/Shell/Recognizer/verbose_trap-in-stl-callback.test @@ -0,0 +1,21 @@ +# Tests that we show the first non-STL frame when +# a verbose_trap triggers from within the STL. +# +# Specifically tests that we correctly handle backtraces +# of the form: +# #0 __builtin_verbose_trap +# #1 STL +# #2 user-code +# #3 STL +# #4 user-code + +# UNSUPPORTED: system-windows +# +# RUN: %clang_host -g -O0 %S/Inputs/verbose_trap-in-stl-callback.cpp -o %t.out +# RUN: %lldb -b -s %s %t.out | FileCheck %s --check-prefixes=CHECK + +run +# CHECK: thread #{{.*}}stop reason = Failed: Invariant violated +frame info +# CHECK: frame #{{.*}}`g() at verbose_trap-in-stl-callback.cpp +q diff --git a/lldb/test/Shell/Recognizer/verbose_trap-in-stl-max-depth.test b/lldb/test/Shell/Recognizer/verbose_trap-in-stl-max-depth.test new file mode 100644 index 00000000000000..0c3275c571b3d9 --- /dev/null +++ b/lldb/test/Shell/Recognizer/verbose_trap-in-stl-max-depth.test @@ -0,0 +1,16 @@ +# Tests that the VerboseTrapFrameRecognizer stops +# walking the stack once a certain implementation-defined +# threshold is reached. + +# UNSUPPORTED: system-windows +# +# RUN: %clang_host -g -O0 %S/Inputs/verbose_trap-in-stl-max-depth.cpp -o %t.out +# RUN: %lldb -b -s %s %t.out | FileCheck %s --check-prefixes=CHECK + +run +# CHECK: thread #{{.*}}stop reason = +frame recognizer info 0 +# CHECK: frame 0 is recognized by Verbose Trap StackFrame Recognizer +frame info +# CHECK: frame #0: {{.*}}`std::recursively_aborts(int) {{.*}} at verbose_trap-in-stl-max-depth.cpp +q diff --git a/lldb/test/Shell/Recognizer/verbose_trap-in-stl-nested.test b/lldb/test/Shell/Recognizer/verbose_trap-in-stl-nested.test new file mode 100644 index 00000000000000..81a492d1ed5791 --- /dev/null +++ b/lldb/test/Shell/Recognizer/verbose_trap-in-stl-nested.test @@ -0,0 +1,13 @@ +# Tests that we show the first non-STL frame when +# a verbose_trap triggers from within the STL. + +# UNSUPPORTED: system-windows +# +# RUN: %clang_host -g -O0 %S/Inputs/verbose_trap-in-stl-nested.cpp -o %t.out +# RUN: %lldb -b -s %s %t.out | FileCheck %s --check-prefixes=CHECK + +run +# CHECK: thread #{{.*}}stop reason = Bounds error: out-of-bounds access +frame info +# CHECK: frame #{{.*}}`g() at verbose_trap-in-stl-nested.cpp +q diff --git a/lldb/test/Shell/Recognizer/verbose_trap-in-stl.test b/lldb/test/Shell/Recognizer/verbose_trap-in-stl.test new file mode 100644 index 00000000000000..dd08290174e3af --- /dev/null +++ b/lldb/test/Shell/Recognizer/verbose_trap-in-stl.test @@ -0,0 +1,13 @@ +# Tests that we show the first non-STL frame when +# a verbose_trap triggers from within the STL. + +# UNSUPPORTED: system-windows +# +# RUN: %clang_host -g -O0 %S/Inputs/verbose_trap-in-stl.cpp -o %t.out +# RUN: %lldb -b -s %s %t.out | FileCheck %s --check-prefixes=CHECK + +run +# CHECK: thread #{{.*}}stop reason = Bounds error: out-of-bounds access +frame info +# CHECK: frame #{{.*}}`g() at verbose_trap-in-stl.cpp +q