//===-- ThreadPlanStepInstruction.cpp ---------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// C Includes
// C++ Includes
// Other libraries and framework includes
// Project includes
#include "lldb/Target/ThreadPlanStepInstruction.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/StopInfo.h"
#include "lldb/Target/Target.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/Stream.h"
using namespace lldb;
using namespace lldb_private;
//----------------------------------------------------------------------
// ThreadPlanStepInstruction: Step over the current instruction
//----------------------------------------------------------------------
ThreadPlanStepInstruction::ThreadPlanStepInstruction(Thread &thread,
bool step_over,
bool stop_other_threads,
Vote stop_vote,
Vote run_vote)
: ThreadPlan(ThreadPlan::eKindStepInstruction,
"Step over single instruction", thread, stop_vote, run_vote),
m_instruction_addr(0), m_stop_other_threads(stop_other_threads),
m_step_over(step_over) {
m_takes_iteration_count = true;
SetUpState();
}
ThreadPlanStepInstruction::~ThreadPlanStepInstruction() = default;
void ThreadPlanStepInstruction::SetUpState() {
m_instruction_addr = m_thread.GetRegisterContext()->GetPC(0);
StackFrameSP start_frame_sp(m_thread.GetStackFrameAtIndex(0));
m_stack_id = start_frame_sp->GetStackID();
m_start_has_symbol =
start_frame_sp->GetSymbolContext(eSymbolContextSymbol).symbol != nullptr;
StackFrameSP parent_frame_sp = m_thread.GetStackFrameAtIndex(1);
if (parent_frame_sp)
m_parent_frame_id = parent_frame_sp->GetStackID();
}
void ThreadPlanStepInstruction::GetDescription(Stream *s,
lldb::DescriptionLevel level) {
if (level == lldb::eDescriptionLevelBrief) {
if (m_step_over)
s->Printf("instruction step over");
else
s->Printf("instruction step into");
} else {
s->Printf("Stepping one instruction past ");
s->Address(m_instruction_addr, sizeof(addr_t));
if (!m_start_has_symbol)
s->Printf(" which has no symbol");
if (m_step_over)
s->Printf(" stepping over calls");
else
s->Printf(" stepping into calls");
}
}
bool ThreadPlanStepInstruction::ValidatePlan(Stream *error) {
// Since we read the instruction we're stepping over from the thread,
// this plan will always work.
return true;
}
bool ThreadPlanStepInstruction::DoPlanExplainsStop(Event *event_ptr) {
StopInfoSP stop_info_sp = GetPrivateStopInfo();
if (stop_info_sp) {
StopReason reason = stop_info_sp->GetStopReason();
return (reason == eStopReasonTrace || reason == eStopReasonNone);
}
return false;
}
bool ThreadPlanStepInstruction::IsPlanStale() {
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
StackID cur_frame_id = m_thread.GetStackFrameAtIndex(0)->GetStackID();
if (cur_frame_id == m_stack_id) {
// Set plan Complete when we reach next instruction
uint64_t pc = m_thread.GetRegisterContext()->GetPC(0);
uint32_t max_opcode_size = m_thread.CalculateTarget()
->GetArchitecture().GetMaximumOpcodeByteSize();
bool next_instruction_reached = (pc > m_instruction_addr) &&
(pc <= m_instruction_addr + max_opcode_size);
if (next_instruction_reached) {
SetPlanComplete();
}
return (m_thread.GetRegisterContext()->GetPC(0) != m_instruction_addr);
} else if (cur_frame_id < m_stack_id) {
// If the current frame is younger than the start frame and we are stepping
// over, then we need to continue,
// but if we are doing just one step, we're done.
return !m_step_over;
} else {
if (log) {
log->Printf("ThreadPlanStepInstruction::IsPlanStale - Current frame is "
"older than start frame, plan is stale.");
}
return true;
}
}
bool ThreadPlanStepInstruction::ShouldStop(Event *event_ptr) {
if (m_step_over) {
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
StackFrameSP cur_frame_sp = m_thread.GetStackFrameAtIndex(0);
if (!cur_frame_sp) {
if (log)
log->Printf(
"ThreadPlanStepInstruction couldn't get the 0th frame, stopping.");
SetPlanComplete();
return true;
}
StackID cur_frame_zero_id = cur_frame_sp->GetStackID();
if (cur_frame_zero_id == m_stack_id || m_stack_id < cur_frame_zero_id) {
if (m_thread.GetRegisterContext()->GetPC(0) != m_instruction_addr) {
if (--m_iteration_count <= 0) {
SetPlanComplete();
return true;
} else {
// We are still stepping, reset the start pc, and in case we've
// stepped out,
// reset the current stack id.
SetUpState();
return false;
}
} else
return false;
} else {
// We've stepped in, step back out again:
StackFrame *return_frame = m_thread.GetStackFrameAtIndex(1).get();
if (return_frame) {
if (return_frame->GetStackID() != m_parent_frame_id ||
m_start_has_symbol) {
// next-instruction shouldn't step out of inlined functions. But we
// may have stepped into a
// real function that starts with an inlined function, and we do want
// to step out of that...
if (cur_frame_sp->IsInlined()) {
StackFrameSP parent_frame_sp =
m_thread.GetFrameWithStackID(m_stack_id);
if (parent_frame_sp &&
parent_frame_sp->GetConcreteFrameIndex() ==
cur_frame_sp->GetConcreteFrameIndex()) {
SetPlanComplete();
if (log) {
log->Printf("Frame we stepped into is inlined into the frame "
"we were stepping from, stopping.");
}
return true;
}
}
if (log) {
StreamString s;
s.PutCString("Stepped in to: ");
addr_t stop_addr =
m_thread.GetStackFrameAtIndex(0)->GetRegisterContext()->GetPC();
s.Address(stop_addr, m_thread.CalculateTarget()
->GetArchitecture()
.GetAddressByteSize());
s.PutCString(" stepping out to: ");
addr_t return_addr = return_frame->GetRegisterContext()->GetPC();
s.Address(return_addr, m_thread.CalculateTarget()
->GetArchitecture()
.GetAddressByteSize());
log->Printf("%s.", s.GetData());
}
// StepInstruction should probably have the tri-state RunMode, but for
// now it is safer to
// run others.
const bool stop_others = false;
m_thread.QueueThreadPlanForStepOutNoShouldStop(
false, nullptr, true, stop_others, eVoteNo, eVoteNoOpinion, 0);
return false;
} else {
if (log) {
log->PutCString(
"The stack id we are stepping in changed, but our parent frame "
"did not when stepping from code with no symbols. "
"We are probably just confused about where we are, stopping.");
}
SetPlanComplete();
return true;
}
} else {
if (log)
log->Printf("Could not find previous frame, stopping.");
SetPlanComplete();
return true;
}
}
} else {
lldb::addr_t pc_addr = m_thread.GetRegisterContext()->GetPC(0);
if (pc_addr != m_instruction_addr) {
if (--m_iteration_count <= 0) {
SetPlanComplete();
return true;
} else {
// We are still stepping, reset the start pc, and in case we've stepped
// in or out,
// reset the current stack id.
SetUpState();
return false;
}
} else
return false;
}
}
bool ThreadPlanStepInstruction::StopOthers() { return m_stop_other_threads; }
StateType ThreadPlanStepInstruction::GetPlanRunState() {
return eStateStepping;
}
bool ThreadPlanStepInstruction::WillStop() { return true; }
bool ThreadPlanStepInstruction::MischiefManaged() {
if (IsPlanComplete()) {
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
if (log)
log->Printf("Completed single instruction step plan.");
ThreadPlan::MischiefManaged();
return true;
} else {
return false;
}
}