Fix pc/function name for signal handler frame.
This refactors the step function slightly to split it up into
distinct pieces since the code needs to handle a signal handler
versus normal step slightly differently.
Add a new error for an invalid elf.
Modify libbacktrace code to handle new error code.
Bug: 130302288
Test: libbacktrace/libunwindstack unit tests.
Change-Id: I3fb9b00c02d2cf2cc5911541bba0346c6f39b8e6
Merged-In: I3fb9b00c02d2cf2cc5911541bba0346c6f39b8e6
(cherry picked from commit d11ed86d65e870c5ea0d4918693376d474dbfe7d)
diff --git a/libunwindstack/Unwinder.cpp b/libunwindstack/Unwinder.cpp
index 3f2e1c1..f3d2b5e 100644
--- a/libunwindstack/Unwinder.cpp
+++ b/libunwindstack/Unwinder.cpp
@@ -89,8 +89,8 @@
#endif
}
-void Unwinder::FillInFrame(MapInfo* map_info, Elf* elf, uint64_t rel_pc, uint64_t func_pc,
- uint64_t pc_adjustment) {
+FrameData* Unwinder::FillInFrame(MapInfo* map_info, Elf* elf, uint64_t rel_pc,
+ uint64_t pc_adjustment) {
size_t frame_num = frames_.size();
frames_.resize(frame_num + 1);
FrameData* frame = &frames_.at(frame_num);
@@ -100,7 +100,8 @@
frame->pc = regs_->pc() - pc_adjustment;
if (map_info == nullptr) {
- return;
+ // Nothing else to update.
+ return nullptr;
}
if (resolve_names_) {
@@ -118,12 +119,7 @@
frame->map_end = map_info->end;
frame->map_flags = map_info->flags;
frame->map_load_bias = elf->GetLoadBias();
-
- if (!resolve_names_ ||
- !elf->GetFunctionName(func_pc, &frame->function_name, &frame->function_offset)) {
- frame->function_name = "";
- frame->function_offset = 0;
- }
+ return frame;
}
static bool ShouldStop(const std::vector<std::string>* map_suffixes_to_ignore,
@@ -194,6 +190,7 @@
}
}
+ FrameData* frame = nullptr;
if (map_info == nullptr || initial_map_names_to_skip == nullptr ||
std::find(initial_map_names_to_skip->begin(), initial_map_names_to_skip->end(),
basename(map_info->name.c_str())) == initial_map_names_to_skip->end()) {
@@ -210,23 +207,21 @@
}
}
- FillInFrame(map_info, elf, rel_pc, step_pc, pc_adjustment);
+ frame = FillInFrame(map_info, elf, rel_pc, pc_adjustment);
// Once a frame is added, stop skipping frames.
initial_map_names_to_skip = nullptr;
}
adjust_pc = true;
- bool stepped;
+ bool stepped = false;
bool in_device_map = false;
- if (map_info == nullptr) {
- stepped = false;
- } else {
+ bool finished = false;
+ if (map_info != nullptr) {
if (map_info->flags & MAPS_FLAGS_DEVICE_MAP) {
// Do not stop here, fall through in case we are
// in the speculative unwind path and need to remove
// some of the speculative frames.
- stepped = false;
in_device_map = true;
} else {
MapInfo* sp_info = maps_->Find(regs_->sp());
@@ -234,19 +229,37 @@
// Do not stop here, fall through in case we are
// in the speculative unwind path and need to remove
// some of the speculative frames.
- stepped = false;
in_device_map = true;
} else {
- bool finished;
- stepped = elf->Step(rel_pc, step_pc, regs_, process_memory_.get(), &finished);
- elf->GetLastError(&last_error_);
- if (stepped && finished) {
- break;
+ if (elf->StepIfSignalHandler(rel_pc, regs_, process_memory_.get())) {
+ stepped = true;
+ if (frame != nullptr) {
+ // Need to adjust the relative pc because the signal handler
+ // pc should not be adjusted.
+ frame->rel_pc = rel_pc;
+ frame->pc += pc_adjustment;
+ step_pc = rel_pc;
+ }
+ } else if (elf->Step(step_pc, regs_, process_memory_.get(), &finished)) {
+ stepped = true;
}
+ elf->GetLastError(&last_error_);
}
}
}
+ if (frame != nullptr) {
+ if (!resolve_names_ ||
+ !elf->GetFunctionName(step_pc, &frame->function_name, &frame->function_offset)) {
+ frame->function_name = "";
+ frame->function_offset = 0;
+ }
+ }
+
+ if (finished) {
+ break;
+ }
+
if (!stepped) {
if (return_address_attempt) {
// Only remove the speculative frame if there are more than two frames