llvm-project/lldb/source/Target/ThreadPlanStepOverRange.cpp

435 lines
19 KiB
C++

//===-- 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)
{
if (m_addr_context.function && m_addr_context.function == context.function)
{
if (m_addr_context.block && m_addr_context.block == context.block)
return true;
}
}
}
else 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.file != m_addr_context.line_entry.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 <source-fragment.c> directly.
LineEntry prev_line_entry;
if (line_table->GetLineEntryAtIndex(entry_idx - 1, prev_line_entry)
&& prev_line_entry.file == line_entry.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.file == m_addr_context.line_entry.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 = "<unknown-notinlined>";
s.Printf ("Stepping over inlined function \"%s\" in inlined stack: ", name);
DumpRanges(&s);
log->PutCString(s.GetData());
}
}
}
}
}
}
return true;
}