//===-- ThreadPlanStepOverRange.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/ThreadPlanStepOverRange.h" #include "lldb/Core/Log.h" #include "lldb/Core/Stream.h" #include "lldb/Symbol/Block.h" #include "lldb/Symbol/CompileUnit.h" #include "lldb/Symbol/Function.h" #include "lldb/Symbol/LineTable.h" #include "lldb/Target/Process.h" #include "lldb/Target/RegisterContext.h" #include "lldb/Target/Target.h" #include "lldb/Target/Thread.h" #include "lldb/Target/ThreadPlanStepOut.h" #include "lldb/Target/ThreadPlanStepThrough.h" using namespace lldb_private; using namespace lldb; uint32_t ThreadPlanStepOverRange::s_default_flag_values = 0; //---------------------------------------------------------------------- // ThreadPlanStepOverRange: Step through a stack range, either stepping over or // into // based on the value of \a type. //---------------------------------------------------------------------- ThreadPlanStepOverRange::ThreadPlanStepOverRange( Thread &thread, const AddressRange &range, const SymbolContext &addr_context, lldb::RunMode stop_others, LazyBool step_out_avoids_code_without_debug_info) : ThreadPlanStepRange(ThreadPlan::eKindStepOverRange, "Step range stepping over", thread, range, addr_context, stop_others), ThreadPlanShouldStopHere(this), m_first_resume(true) { SetFlagsToDefault(); SetupAvoidNoDebug(step_out_avoids_code_without_debug_info); } ThreadPlanStepOverRange::~ThreadPlanStepOverRange() = default; void ThreadPlanStepOverRange::GetDescription(Stream *s, lldb::DescriptionLevel level) { if (level == lldb::eDescriptionLevelBrief) { s->Printf("step over"); return; } s->Printf("Stepping over"); bool printed_line_info = false; if (m_addr_context.line_entry.IsValid()) { s->Printf(" line "); m_addr_context.line_entry.DumpStopContext(s, false); printed_line_info = true; } if (!printed_line_info || level == eDescriptionLevelVerbose) { s->Printf(" using ranges: "); DumpRanges(s); } s->PutChar('.'); } void ThreadPlanStepOverRange::SetupAvoidNoDebug( LazyBool step_out_avoids_code_without_debug_info) { bool avoid_nodebug = true; switch (step_out_avoids_code_without_debug_info) { case eLazyBoolYes: avoid_nodebug = true; break; case eLazyBoolNo: avoid_nodebug = false; break; case eLazyBoolCalculate: avoid_nodebug = m_thread.GetStepOutAvoidsNoDebug(); break; } if (avoid_nodebug) GetFlags().Set(ThreadPlanShouldStopHere::eStepOutAvoidNoDebug); else GetFlags().Clear(ThreadPlanShouldStopHere::eStepOutAvoidNoDebug); // Step Over plans should always avoid no-debug on step in. Seems like you // shouldn't // have to say this, but a tail call looks more like a step in that a step // out, so // we want to catch this case. GetFlags().Set(ThreadPlanShouldStopHere::eStepInAvoidNoDebug); } bool ThreadPlanStepOverRange::IsEquivalentContext( const SymbolContext &context) { // Match as much as is specified in the m_addr_context: // This is a fairly loose sanity check. Note, sometimes the target doesn't // get filled // in so I left out the target check. And sometimes the module comes in as // the .o file from the // inlined range, so I left that out too... if (m_addr_context.comp_unit) { if (m_addr_context.comp_unit != context.comp_unit) return false; if (m_addr_context.function) { if (m_addr_context.function != context.function) return false; // It is okay to return to a different block of a straight function, we // only have to // be more careful if returning from one inlined block to another. if (m_addr_context.block->GetInlinedFunctionInfo() == nullptr && context.block->GetInlinedFunctionInfo() == nullptr) return true; return m_addr_context.block == context.block; } } // Fall back to symbol if we have no decision from comp_unit/function/block. if (m_addr_context.symbol && m_addr_context.symbol == context.symbol) { return true; } return false; } bool ThreadPlanStepOverRange::ShouldStop(Event *event_ptr) { Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP)); if (log) { StreamString s; s.Address( m_thread.GetRegisterContext()->GetPC(), m_thread.CalculateTarget()->GetArchitecture().GetAddressByteSize()); log->Printf("ThreadPlanStepOverRange reached %s.", s.GetData()); } // If we're out of the range but in the same frame or in our caller's frame // then we should stop. // When stepping out we only stop others if we are forcing running one thread. bool stop_others = (m_stop_others == lldb::eOnlyThisThread); ThreadPlanSP new_plan_sp; FrameComparison frame_order = CompareCurrentFrameToStartFrame(); if (frame_order == eFrameCompareOlder) { // If we're in an older frame then we should stop. // // A caveat to this is if we think the frame is older but we're actually in // a trampoline. // I'm going to make the assumption that you wouldn't RETURN to a // trampoline. So if we are // in a trampoline we think the frame is older because the trampoline // confused the backtracer. // As below, we step through first, and then try to figure out how to get // back out again. new_plan_sp = m_thread.QueueThreadPlanForStepThrough(m_stack_id, false, stop_others); if (new_plan_sp && log) log->Printf( "Thought I stepped out, but in fact arrived at a trampoline."); } else if (frame_order == eFrameCompareYounger) { // Make sure we really are in a new frame. Do that by unwinding and seeing // if the // start function really is our start function... for (uint32_t i = 1;; ++i) { StackFrameSP older_frame_sp = m_thread.GetStackFrameAtIndex(i); if (!older_frame_sp) { // We can't unwind the next frame we should just get out of here & // stop... break; } const SymbolContext &older_context = older_frame_sp->GetSymbolContext(eSymbolContextEverything); if (IsEquivalentContext(older_context)) { new_plan_sp = m_thread.QueueThreadPlanForStepOutNoShouldStop( false, nullptr, true, stop_others, eVoteNo, eVoteNoOpinion, 0, true); break; } else { new_plan_sp = m_thread.QueueThreadPlanForStepThrough(m_stack_id, false, stop_others); // If we found a way through, then we should stop recursing. if (new_plan_sp) break; } } } else { // If we're still in the range, keep going. if (InRange()) { SetNextBranchBreakpoint(); return false; } if (!InSymbol()) { // This one is a little tricky. Sometimes we may be in a stub or // something similar, // in which case we need to get out of there. But if we are in a stub // then it's // likely going to be hard to get out from here. It is probably easiest // to step into the // stub, and then it will be straight-forward to step out. new_plan_sp = m_thread.QueueThreadPlanForStepThrough(m_stack_id, false, stop_others); } else { // The current clang (at least through 424) doesn't always get the address // range for the // DW_TAG_inlined_subroutines right, so that when you leave the inlined // range the line table says // you are still in the source file of the inlining function. This is // bad, because now you are missing // the stack frame for the function containing the inlining, and if you // sensibly do "finish" to get // out of this function you will instead exit the containing function. // To work around this, we check whether we are still in the source file // we started in, and if not assume // it is an error, and push a plan to get us out of this line and back to // the containing file. if (m_addr_context.line_entry.IsValid()) { SymbolContext sc; StackFrameSP frame_sp = m_thread.GetStackFrameAtIndex(0); sc = frame_sp->GetSymbolContext(eSymbolContextEverything); if (sc.line_entry.IsValid()) { if (sc.line_entry.original_file != m_addr_context.line_entry.original_file && sc.comp_unit == m_addr_context.comp_unit && sc.function == m_addr_context.function) { // Okay, find the next occurrence of this file in the line table: LineTable *line_table = m_addr_context.comp_unit->GetLineTable(); if (line_table) { Address cur_address = frame_sp->GetFrameCodeAddress(); uint32_t entry_idx; LineEntry line_entry; if (line_table->FindLineEntryByAddress(cur_address, line_entry, &entry_idx)) { LineEntry next_line_entry; bool step_past_remaining_inline = false; if (entry_idx > 0) { // We require the previous line entry and the current line // entry come // from the same file. // The other requirement is that the previous line table entry // be part of an // inlined block, we don't want to step past cases where // people have inlined // some code fragment by using #include // directly. LineEntry prev_line_entry; if (line_table->GetLineEntryAtIndex(entry_idx - 1, prev_line_entry) && prev_line_entry.original_file == line_entry.original_file) { SymbolContext prev_sc; Address prev_address = prev_line_entry.range.GetBaseAddress(); prev_address.CalculateSymbolContext(&prev_sc); if (prev_sc.block) { Block *inlined_block = prev_sc.block->GetContainingInlinedBlock(); if (inlined_block) { AddressRange inline_range; inlined_block->GetRangeContainingAddress(prev_address, inline_range); if (!inline_range.ContainsFileAddress(cur_address)) { step_past_remaining_inline = true; } } } } } if (step_past_remaining_inline) { uint32_t look_ahead_step = 1; while (line_table->GetLineEntryAtIndex( entry_idx + look_ahead_step, next_line_entry)) { // Make sure we haven't wandered out of the function we // started from... Address next_line_address = next_line_entry.range.GetBaseAddress(); Function *next_line_function = next_line_address.CalculateSymbolContextFunction(); if (next_line_function != m_addr_context.function) break; if (next_line_entry.original_file == m_addr_context.line_entry.original_file) { const bool abort_other_plans = false; const RunMode stop_other_threads = RunMode::eAllThreads; lldb::addr_t cur_pc = m_thread.GetStackFrameAtIndex(0) ->GetRegisterContext() ->GetPC(); AddressRange step_range( cur_pc, next_line_address.GetLoadAddress(&GetTarget()) - cur_pc); new_plan_sp = m_thread.QueueThreadPlanForStepOverRange( abort_other_plans, step_range, sc, stop_other_threads); break; } look_ahead_step++; } } } } } } } } } // If we get to this point, we're not going to use a previously set "next // branch" breakpoint, so delete it: ClearNextBranchBreakpoint(); // If we haven't figured out something to do yet, then ask the ShouldStopHere // callback: if (!new_plan_sp) { new_plan_sp = CheckShouldStopHereAndQueueStepOut(frame_order); } if (!new_plan_sp) m_no_more_plans = true; else { // Any new plan will be an implementation plan, so mark it private: new_plan_sp->SetPrivate(true); m_no_more_plans = false; } if (!new_plan_sp) { // For efficiencies sake, we know we're done here so we don't have to do // this // calculation again in MischiefManaged. SetPlanComplete(); return true; } else return false; } bool ThreadPlanStepOverRange::DoPlanExplainsStop(Event *event_ptr) { // For crashes, breakpoint hits, signals, etc, let the base plan (or some plan // above us) // handle the stop. That way the user can see the stop, step around, and then // when they // are done, continue and have their step complete. The exception is if we've // hit our // "run to next branch" breakpoint. // Note, unlike the step in range plan, we don't mark ourselves complete if we // hit an // unexplained breakpoint/crash. Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP)); StopInfoSP stop_info_sp = GetPrivateStopInfo(); bool return_value; if (stop_info_sp) { StopReason reason = stop_info_sp->GetStopReason(); if (reason == eStopReasonTrace) { return_value = true; } else if (reason == eStopReasonBreakpoint) { return_value = NextRangeBreakpointExplainsStop(stop_info_sp); } else { if (log) log->PutCString("ThreadPlanStepInRange got asked if it explains the " "stop for some reason other than step."); return_value = false; } } else return_value = true; return return_value; } bool ThreadPlanStepOverRange::DoWillResume(lldb::StateType resume_state, bool current_plan) { if (resume_state != eStateSuspended && m_first_resume) { m_first_resume = false; if (resume_state == eStateStepping && current_plan) { // See if we are about to step over an inlined call in the middle of the // inlined stack, if so figure // out its extents and reset our range to step over that. bool in_inlined_stack = m_thread.DecrementCurrentInlinedDepth(); if (in_inlined_stack) { Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP)); if (log) log->Printf("ThreadPlanStepInRange::DoWillResume: adjusting range to " "the frame at inlined depth %d.", m_thread.GetCurrentInlinedDepth()); StackFrameSP stack_sp = m_thread.GetStackFrameAtIndex(0); if (stack_sp) { Block *frame_block = stack_sp->GetFrameBlock(); lldb::addr_t curr_pc = m_thread.GetRegisterContext()->GetPC(); AddressRange my_range; if (frame_block->GetRangeContainingLoadAddress( curr_pc, m_thread.GetProcess()->GetTarget(), my_range)) { m_address_ranges.clear(); m_address_ranges.push_back(my_range); if (log) { StreamString s; const InlineFunctionInfo *inline_info = frame_block->GetInlinedFunctionInfo(); const char *name; if (inline_info) name = inline_info ->GetName(frame_block->CalculateSymbolContextFunction() ->GetLanguage()) .AsCString(); else name = ""; s.Printf( "Stepping over inlined function \"%s\" in inlined stack: ", name); DumpRanges(&s); log->PutString(s.GetString()); } } } } } } return true; }