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Diffstat (limited to 'source/Symbol/FuncUnwinders.cpp')
-rw-r--r--source/Symbol/FuncUnwinders.cpp133
1 files changed, 97 insertions, 36 deletions
diff --git a/source/Symbol/FuncUnwinders.cpp b/source/Symbol/FuncUnwinders.cpp
index 3b94e250dac7..b9f50cd1b12f 100644
--- a/source/Symbol/FuncUnwinders.cpp
+++ b/source/Symbol/FuncUnwinders.cpp
@@ -39,7 +39,9 @@ FuncUnwinders::FuncUnwinders(UnwindTable &unwind_table, AddressRange range)
m_unwind_plan_arch_default_sp(),
m_unwind_plan_arch_default_at_func_entry_sp(),
m_tried_unwind_plan_assembly(false), m_tried_unwind_plan_eh_frame(false),
+ m_tried_unwind_plan_debug_frame(false),
m_tried_unwind_plan_eh_frame_augmented(false),
+ m_tried_unwind_plan_debug_frame_augmented(false),
m_tried_unwind_plan_compact_unwind(false),
m_tried_unwind_plan_arm_unwind(false), m_tried_unwind_fast(false),
m_tried_unwind_arch_default(false),
@@ -56,17 +58,14 @@ UnwindPlanSP FuncUnwinders::GetUnwindPlanAtCallSite(Target &target,
int current_offset) {
std::lock_guard<std::recursive_mutex> guard(m_mutex);
- UnwindPlanSP unwind_plan_sp = GetEHFrameUnwindPlan(target, current_offset);
- if (unwind_plan_sp)
- return unwind_plan_sp;
-
- unwind_plan_sp = GetCompactUnwindUnwindPlan(target, current_offset);
- if (unwind_plan_sp)
- return unwind_plan_sp;
-
- unwind_plan_sp = GetArmUnwindUnwindPlan(target, current_offset);
- if (unwind_plan_sp)
- return unwind_plan_sp;
+ if (UnwindPlanSP plan_sp = GetEHFrameUnwindPlan(target, current_offset))
+ return plan_sp;
+ if (UnwindPlanSP plan_sp = GetDebugFrameUnwindPlan(target, current_offset))
+ return plan_sp;
+ if (UnwindPlanSP plan_sp = GetCompactUnwindUnwindPlan(target, current_offset))
+ return plan_sp;
+ if (UnwindPlanSP plan_sp = GetArmUnwindUnwindPlan(target, current_offset))
+ return plan_sp;
return nullptr;
}
@@ -121,6 +120,29 @@ UnwindPlanSP FuncUnwinders::GetEHFrameUnwindPlan(Target &target,
return m_unwind_plan_eh_frame_sp;
}
+UnwindPlanSP FuncUnwinders::GetDebugFrameUnwindPlan(Target &target,
+ int current_offset) {
+ std::lock_guard<std::recursive_mutex> guard(m_mutex);
+ if (m_unwind_plan_debug_frame_sp || m_tried_unwind_plan_debug_frame)
+ return m_unwind_plan_debug_frame_sp;
+
+ m_tried_unwind_plan_debug_frame = true;
+ if (m_range.GetBaseAddress().IsValid()) {
+ Address current_pc(m_range.GetBaseAddress());
+ if (current_offset != -1)
+ current_pc.SetOffset(current_pc.GetOffset() + current_offset);
+ DWARFCallFrameInfo *debug_frame = m_unwind_table.GetDebugFrameInfo();
+ if (debug_frame) {
+ m_unwind_plan_debug_frame_sp.reset(
+ new UnwindPlan(lldb::eRegisterKindGeneric));
+ if (!debug_frame->GetUnwindPlan(current_pc,
+ *m_unwind_plan_debug_frame_sp))
+ m_unwind_plan_debug_frame_sp.reset();
+ }
+ }
+ return m_unwind_plan_debug_frame_sp;
+}
+
UnwindPlanSP FuncUnwinders::GetArmUnwindUnwindPlan(Target &target,
int current_offset) {
std::lock_guard<std::recursive_mutex> guard(m_mutex);
@@ -187,6 +209,48 @@ UnwindPlanSP FuncUnwinders::GetEHFrameAugmentedUnwindPlan(Target &target,
return m_unwind_plan_eh_frame_augmented_sp;
}
+UnwindPlanSP
+FuncUnwinders::GetDebugFrameAugmentedUnwindPlan(Target &target, Thread &thread,
+ int current_offset) {
+ std::lock_guard<std::recursive_mutex> guard(m_mutex);
+ if (m_unwind_plan_debug_frame_augmented_sp.get() ||
+ m_tried_unwind_plan_debug_frame_augmented)
+ return m_unwind_plan_debug_frame_augmented_sp;
+
+ // Only supported on x86 architectures where we get debug_frame from the
+ // compiler that describes the prologue instructions perfectly, and sometimes
+ // the epilogue instructions too.
+ if (target.GetArchitecture().GetCore() != ArchSpec::eCore_x86_32_i386 &&
+ target.GetArchitecture().GetCore() != ArchSpec::eCore_x86_64_x86_64 &&
+ target.GetArchitecture().GetCore() != ArchSpec::eCore_x86_64_x86_64h) {
+ m_tried_unwind_plan_debug_frame_augmented = true;
+ return m_unwind_plan_debug_frame_augmented_sp;
+ }
+
+ m_tried_unwind_plan_debug_frame_augmented = true;
+
+ UnwindPlanSP debug_frame_plan =
+ GetDebugFrameUnwindPlan(target, current_offset);
+ if (!debug_frame_plan)
+ return m_unwind_plan_debug_frame_augmented_sp;
+
+ m_unwind_plan_debug_frame_augmented_sp.reset(
+ new UnwindPlan(*debug_frame_plan));
+
+ // Augment the debug_frame instructions with epilogue descriptions if
+ // necessary so the UnwindPlan can be used at any instruction in the function.
+
+ UnwindAssemblySP assembly_profiler_sp(GetUnwindAssemblyProfiler(target));
+ if (assembly_profiler_sp) {
+ if (!assembly_profiler_sp->AugmentUnwindPlanFromCallSite(
+ m_range, thread, *m_unwind_plan_debug_frame_augmented_sp)) {
+ m_unwind_plan_debug_frame_augmented_sp.reset();
+ }
+ } else
+ m_unwind_plan_debug_frame_augmented_sp.reset();
+ return m_unwind_plan_debug_frame_augmented_sp;
+}
+
UnwindPlanSP FuncUnwinders::GetAssemblyUnwindPlan(Target &target,
Thread &thread,
int current_offset) {
@@ -248,6 +312,8 @@ UnwindPlanSP FuncUnwinders::GetUnwindPlanAtNonCallSite(Target &target,
Thread &thread,
int current_offset) {
UnwindPlanSP eh_frame_sp = GetEHFrameUnwindPlan(target, current_offset);
+ if (!eh_frame_sp)
+ eh_frame_sp = GetDebugFrameUnwindPlan(target, current_offset);
UnwindPlanSP arch_default_at_entry_sp =
GetUnwindPlanArchitectureDefaultAtFunctionEntry(thread);
UnwindPlanSP arch_default_sp = GetUnwindPlanArchitectureDefault(thread);
@@ -255,28 +321,22 @@ UnwindPlanSP FuncUnwinders::GetUnwindPlanAtNonCallSite(Target &target,
GetAssemblyUnwindPlan(target, thread, current_offset);
// This point of this code is to detect when a function is using a
- // non-standard ABI, and the eh_frame
- // correctly describes that alternate ABI. This is addressing a specific
- // situation on x86_64 linux
- // systems where one function in a library pushes a value on the stack and
- // jumps to another function.
- // So using an assembly instruction based unwind will not work when you're in
- // the second function -
- // the stack has been modified in a non-ABI way. But we have eh_frame that
- // correctly describes how to
- // unwind from this location. So we're looking to see if the initial pc
- // register save location from
- // the eh_frame is different from the assembly unwind, the arch default
- // unwind, and the arch default at
- // initial function entry.
+ // non-standard ABI, and the eh_frame correctly describes that alternate ABI.
+ // This is addressing a specific situation on x86_64 linux systems where one
+ // function in a library pushes a value on the stack and jumps to another
+ // function. So using an assembly instruction based unwind will not work when
+ // you're in the second function - the stack has been modified in a non-ABI
+ // way. But we have eh_frame that correctly describes how to unwind from this
+ // location. So we're looking to see if the initial pc register save location
+ // from the eh_frame is different from the assembly unwind, the arch default
+ // unwind, and the arch default at initial function entry.
//
// We may have eh_frame that describes the entire function -- or we may have
- // eh_frame that only describes
- // the unwind after the prologue has executed -- so we need to check both the
- // arch default (once the prologue
- // has executed) and the arch default at initial function entry. And we may
- // be running on a target where
- // we have only some of the assembly/arch default unwind plans available.
+ // eh_frame that only describes the unwind after the prologue has executed --
+ // so we need to check both the arch default (once the prologue has executed)
+ // and the arch default at initial function entry. And we may be running on a
+ // target where we have only some of the assembly/arch default unwind plans
+ // available.
if (CompareUnwindPlansForIdenticalInitialPCLocation(
thread, eh_frame_sp, arch_default_at_entry_sp) == eLazyBoolNo &&
@@ -287,11 +347,12 @@ UnwindPlanSP FuncUnwinders::GetUnwindPlanAtNonCallSite(Target &target,
return eh_frame_sp;
}
- UnwindPlanSP eh_frame_augmented_sp =
- GetEHFrameAugmentedUnwindPlan(target, thread, current_offset);
- if (eh_frame_augmented_sp) {
- return eh_frame_augmented_sp;
- }
+ if (UnwindPlanSP plan_sp =
+ GetEHFrameAugmentedUnwindPlan(target, thread, current_offset))
+ return plan_sp;
+ if (UnwindPlanSP plan_sp =
+ GetDebugFrameAugmentedUnwindPlan(target, thread, current_offset))
+ return plan_sp;
return assembly_sp;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-09 14:13:42 +0000