Skip to content
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 4 additions & 0 deletions lldb/include/lldb/Target/ThreadPlanStepOut.h
Original file line number Diff line number Diff line change
Expand Up @@ -82,6 +82,10 @@ class ThreadPlanStepOut : public ThreadPlan, public ThreadPlanShouldStopHere {
LazyBool step_out_avoids_code_without_debug_info);

void SetupAvoidNoDebug(LazyBool step_out_avoids_code_without_debug_info);

void SetupReturnAddress(lldb::StackFrameSP return_frame_sp,
lldb::StackFrameSP immediate_return_from_sp,
uint32_t frame_idx, bool continue_to_next_branch);
// Need an appropriate marker for the current stack so we can tell step out
// from step in.

Expand Down
58 changes: 38 additions & 20 deletions lldb/source/Target/ThreadPlanStepOut.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -31,6 +31,32 @@ using namespace lldb_private;

uint32_t ThreadPlanStepOut::s_default_flag_values = 0;

/// Computes the target frame this plan should step out to.
static StackFrameSP
ComputeTargetFrame(Thread &thread, uint32_t start_frame_idx,
std::vector<StackFrameSP> &skipped_frames) {
uint32_t frame_idx = start_frame_idx + 1;
StackFrameSP return_frame_sp = thread.GetStackFrameAtIndex(frame_idx);
if (!return_frame_sp)
return nullptr;

while (return_frame_sp->IsArtificial() || return_frame_sp->IsHidden()) {
skipped_frames.push_back(return_frame_sp);

frame_idx++;
return_frame_sp = thread.GetStackFrameAtIndex(frame_idx);

// We never expect to see an artificial frame without a regular ancestor.
// Defensively refuse to step out.
if (!return_frame_sp) {
LLDB_LOG(GetLog(LLDBLog::Step),
"Can't step out of frame with artificial ancestors");
return nullptr;
}
}
return return_frame_sp;
}

// ThreadPlanStepOut: Step out of the current frame
ThreadPlanStepOut::ThreadPlanStepOut(
Thread &thread, SymbolContext *context, bool first_insn, bool stop_others,
Expand All @@ -44,34 +70,25 @@ ThreadPlanStepOut::ThreadPlanStepOut(
m_return_addr(LLDB_INVALID_ADDRESS), m_stop_others(stop_others),
m_immediate_step_from_function(nullptr),
m_calculate_return_value(gather_return_value) {
Log *log = GetLog(LLDBLog::Step);
SetFlagsToDefault();
SetupAvoidNoDebug(step_out_avoids_code_without_debug_info);

m_step_from_insn = thread.GetRegisterContext()->GetPC(0);

uint32_t return_frame_index = frame_idx + 1;
StackFrameSP return_frame_sp(thread.GetStackFrameAtIndex(return_frame_index));
StackFrameSP return_frame_sp =
ComputeTargetFrame(thread, frame_idx, m_stepped_past_frames);
StackFrameSP immediate_return_from_sp(thread.GetStackFrameAtIndex(frame_idx));

SetupReturnAddress(return_frame_sp, immediate_return_from_sp, frame_idx,
continue_to_next_branch);
}

void ThreadPlanStepOut::SetupReturnAddress(
StackFrameSP return_frame_sp, StackFrameSP immediate_return_from_sp,
uint32_t frame_idx, bool continue_to_next_branch) {
if (!return_frame_sp || !immediate_return_from_sp)
return; // we can't do anything here. ValidatePlan() will return false.

// While stepping out, behave as-if artificial frames are not present.
while (return_frame_sp->IsArtificial() || return_frame_sp->IsHidden()) {
m_stepped_past_frames.push_back(return_frame_sp);

++return_frame_index;
return_frame_sp = thread.GetStackFrameAtIndex(return_frame_index);

// We never expect to see an artificial frame without a regular ancestor.
// If this happens, log the issue and defensively refuse to step out.
if (!return_frame_sp) {
LLDB_LOG(log, "Can't step out of frame with artificial ancestors");
return;
}
}

m_step_out_to_id = return_frame_sp->GetStackID();
m_immediate_step_from_id = immediate_return_from_sp->GetStackID();

Expand All @@ -84,8 +101,8 @@ ThreadPlanStepOut::ThreadPlanStepOut(
// First queue a plan that gets us to this inlined frame, and when we get
// there we'll queue a second plan that walks us out of this frame.
m_step_out_to_inline_plan_sp = std::make_shared<ThreadPlanStepOut>(
thread, nullptr, false, stop_others, eVoteNoOpinion, eVoteNoOpinion,
frame_idx - 1, eLazyBoolNo, continue_to_next_branch);
GetThread(), nullptr, false, m_stop_others, eVoteNoOpinion,
eVoteNoOpinion, frame_idx - 1, eLazyBoolNo, continue_to_next_branch);
static_cast<ThreadPlanStepOut *>(m_step_out_to_inline_plan_sp.get())
->SetShouldStopHereCallbacks(nullptr, nullptr);
m_step_out_to_inline_plan_sp->SetPrivate(true);
Expand Down Expand Up @@ -125,6 +142,7 @@ ThreadPlanStepOut::ThreadPlanStepOut(

// Perform some additional validation on the return address.
uint32_t permissions = 0;
Log *log = GetLog(LLDBLog::Step);
if (!m_process.GetLoadAddressPermissions(m_return_addr, permissions)) {
LLDB_LOGF(log, "ThreadPlanStepOut(%p): Return address (0x%" PRIx64
") permissions not found.", static_cast<void *>(this),
Expand Down
Loading