--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lldb/source/Target/ThreadPlanStepInRange.cpp	Thu Feb 13 15:10:13 2020 +0900
@@ -0,0 +1,509 @@
+//===-- ThreadPlanStepInRange.cpp -----------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "lldb/Target/ThreadPlanStepInRange.h"
+#include "lldb/Core/Architecture.h"
+#include "lldb/Core/Module.h"
+#include "lldb/Symbol/Function.h"
+#include "lldb/Symbol/Symbol.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Target/RegisterContext.h"
+#include "lldb/Target/SectionLoadList.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Target/Thread.h"
+#include "lldb/Target/ThreadPlanStepOut.h"
+#include "lldb/Target/ThreadPlanStepThrough.h"
+#include "lldb/Utility/Log.h"
+#include "lldb/Utility/RegularExpression.h"
+#include "lldb/Utility/Stream.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+uint32_t ThreadPlanStepInRange::s_default_flag_values =
+    ThreadPlanShouldStopHere::eStepInAvoidNoDebug;
+
+// ThreadPlanStepInRange: Step through a stack range, either stepping over or
+// into based on the value of \a type.
+
+ThreadPlanStepInRange::ThreadPlanStepInRange(
+    Thread &thread, const AddressRange &range,
+    const SymbolContext &addr_context, lldb::RunMode stop_others,
+    LazyBool step_in_avoids_code_without_debug_info,
+    LazyBool step_out_avoids_code_without_debug_info)
+    : ThreadPlanStepRange(ThreadPlan::eKindStepInRange,
+                          "Step Range stepping in", thread, range, addr_context,
+                          stop_others),
+      ThreadPlanShouldStopHere(this), m_step_past_prologue(true),
+      m_virtual_step(false) {
+  SetCallbacks();
+  SetFlagsToDefault();
+  SetupAvoidNoDebug(step_in_avoids_code_without_debug_info,
+                    step_out_avoids_code_without_debug_info);
+}
+
+ThreadPlanStepInRange::ThreadPlanStepInRange(
+    Thread &thread, const AddressRange &range,
+    const SymbolContext &addr_context, const char *step_into_target,
+    lldb::RunMode stop_others, LazyBool step_in_avoids_code_without_debug_info,
+    LazyBool step_out_avoids_code_without_debug_info)
+    : ThreadPlanStepRange(ThreadPlan::eKindStepInRange,
+                          "Step Range stepping in", thread, range, addr_context,
+                          stop_others),
+      ThreadPlanShouldStopHere(this), m_step_past_prologue(true),
+      m_virtual_step(false), m_step_into_target(step_into_target) {
+  SetCallbacks();
+  SetFlagsToDefault();
+  SetupAvoidNoDebug(step_in_avoids_code_without_debug_info,
+                    step_out_avoids_code_without_debug_info);
+}
+
+ThreadPlanStepInRange::~ThreadPlanStepInRange() = default;
+
+void ThreadPlanStepInRange::SetupAvoidNoDebug(
+    LazyBool step_in_avoids_code_without_debug_info,
+    LazyBool step_out_avoids_code_without_debug_info) {
+  bool avoid_nodebug = true;
+
+  switch (step_in_avoids_code_without_debug_info) {
+  case eLazyBoolYes:
+    avoid_nodebug = true;
+    break;
+  case eLazyBoolNo:
+    avoid_nodebug = false;
+    break;
+  case eLazyBoolCalculate:
+    avoid_nodebug = m_thread.GetStepInAvoidsNoDebug();
+    break;
+  }
+  if (avoid_nodebug)
+    GetFlags().Set(ThreadPlanShouldStopHere::eStepInAvoidNoDebug);
+  else
+    GetFlags().Clear(ThreadPlanShouldStopHere::eStepInAvoidNoDebug);
+
+  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);
+}
+
+void ThreadPlanStepInRange::GetDescription(Stream *s,
+                                           lldb::DescriptionLevel level) {
+
+  auto PrintFailureIfAny = [&]() {
+    if (m_status.Success())
+      return;
+    s->Printf(" failed (%s)", m_status.AsCString());
+  };
+
+  if (level == lldb::eDescriptionLevelBrief) {
+    s->Printf("step in");
+    PrintFailureIfAny();
+    return;
+  }
+
+  s->Printf("Stepping in");
+  bool printed_line_info = false;
+  if (m_addr_context.line_entry.IsValid()) {
+    s->Printf(" through line ");
+    m_addr_context.line_entry.DumpStopContext(s, false);
+    printed_line_info = true;
+  }
+
+  const char *step_into_target = m_step_into_target.AsCString();
+  if (step_into_target && step_into_target[0] != '\0')
+    s->Printf(" targeting %s", m_step_into_target.AsCString());
+
+  if (!printed_line_info || level == eDescriptionLevelVerbose) {
+    s->Printf(" using ranges:");
+    DumpRanges(s);
+  }
+
+  PrintFailureIfAny();
+
+  s->PutChar('.');
+}
+
+bool ThreadPlanStepInRange::ShouldStop(Event *event_ptr) {
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+
+  if (log) {
+    StreamString s;
+    DumpAddress(
+        s.AsRawOstream(), m_thread.GetRegisterContext()->GetPC(),
+        m_thread.CalculateTarget()->GetArchitecture().GetAddressByteSize());
+    LLDB_LOGF(log, "ThreadPlanStepInRange reached %s.", s.GetData());
+  }
+
+  if (IsPlanComplete())
+    return true;
+
+  m_no_more_plans = false;
+  if (m_sub_plan_sp && m_sub_plan_sp->IsPlanComplete()) {
+    if (!m_sub_plan_sp->PlanSucceeded()) {
+      SetPlanComplete();
+      m_no_more_plans = true;
+      return true;
+    } else
+      m_sub_plan_sp.reset();
+  }
+
+  if (m_virtual_step) {
+    // If we've just completed a virtual step, all we need to do is check for a
+    // ShouldStopHere plan, and otherwise we're done.
+    // FIXME - This can be both a step in and a step out.  Probably should
+    // record which in the m_virtual_step.
+    m_sub_plan_sp =
+        CheckShouldStopHereAndQueueStepOut(eFrameCompareYounger, m_status);
+  } else {
+    // Stepping through should be done running other threads in general, since
+    // we're setting a breakpoint and continuing.  So only stop others if we
+    // are explicitly told to do so.
+
+    bool stop_others = (m_stop_others == lldb::eOnlyThisThread);
+
+    FrameComparison frame_order = CompareCurrentFrameToStartFrame();
+
+    if (frame_order == eFrameCompareOlder ||
+        frame_order == eFrameCompareSameParent) {
+      // 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.
+      m_sub_plan_sp = m_thread.QueueThreadPlanForStepThrough(
+          m_stack_id, false, stop_others, m_status);
+      if (!m_sub_plan_sp) {
+        // Otherwise check the ShouldStopHere for step out:
+        m_sub_plan_sp =
+            CheckShouldStopHereAndQueueStepOut(frame_order, m_status);
+        if (log) {
+          if (m_sub_plan_sp)
+            LLDB_LOGF(log,
+                      "ShouldStopHere found plan to step out of this frame.");
+          else
+            LLDB_LOGF(log, "ShouldStopHere no plan to step out of this frame.");
+        }
+      } else if (log) {
+        LLDB_LOGF(
+            log, "Thought I stepped out, but in fact arrived at a trampoline.");
+      }
+    } else if (frame_order == eFrameCompareEqual && InSymbol()) {
+      // If we are not in a place we should step through, we're done. One
+      // tricky bit here is that some stubs don't push a frame, so we have to
+      // check both the case of a frame that is younger, or the same as this
+      // frame. However, if the frame is the same, and we are still in the
+      // symbol we started in, the we don't need to do this.  This first check
+      // isn't strictly necessary, but it is more efficient.
+
+      // If we're still in the range, keep going, either by running to the next
+      // branch breakpoint, or by stepping.
+      if (InRange()) {
+        SetNextBranchBreakpoint();
+        return false;
+      }
+
+      SetPlanComplete();
+      m_no_more_plans = true;
+      return true;
+    }
+
+    // If we get to this point, we're not going to use a previously set "next
+    // branch" breakpoint, so delete it:
+    ClearNextBranchBreakpoint();
+
+    // We may have set the plan up above in the FrameIsOlder section:
+
+    if (!m_sub_plan_sp)
+      m_sub_plan_sp = m_thread.QueueThreadPlanForStepThrough(
+          m_stack_id, false, stop_others, m_status);
+
+    if (log) {
+      if (m_sub_plan_sp)
+        LLDB_LOGF(log, "Found a step through plan: %s",
+                  m_sub_plan_sp->GetName());
+      else
+        LLDB_LOGF(log, "No step through plan found.");
+    }
+
+    // If not, give the "should_stop" callback a chance to push a plan to get
+    // us out of here. But only do that if we actually have stepped in.
+    if (!m_sub_plan_sp && frame_order == eFrameCompareYounger)
+      m_sub_plan_sp = CheckShouldStopHereAndQueueStepOut(frame_order, m_status);
+
+    // If we've stepped in and we are going to stop here, check to see if we
+    // were asked to run past the prologue, and if so do that.
+
+    if (!m_sub_plan_sp && frame_order == eFrameCompareYounger &&
+        m_step_past_prologue) {
+      lldb::StackFrameSP curr_frame = m_thread.GetStackFrameAtIndex(0);
+      if (curr_frame) {
+        size_t bytes_to_skip = 0;
+        lldb::addr_t curr_addr = m_thread.GetRegisterContext()->GetPC();
+        Address func_start_address;
+
+        SymbolContext sc = curr_frame->GetSymbolContext(eSymbolContextFunction |
+                                                        eSymbolContextSymbol);
+
+        if (sc.function) {
+          func_start_address = sc.function->GetAddressRange().GetBaseAddress();
+          if (curr_addr ==
+              func_start_address.GetLoadAddress(
+                  m_thread.CalculateTarget().get()))
+            bytes_to_skip = sc.function->GetPrologueByteSize();
+        } else if (sc.symbol) {
+          func_start_address = sc.symbol->GetAddress();
+          if (curr_addr ==
+              func_start_address.GetLoadAddress(
+                  m_thread.CalculateTarget().get()))
+            bytes_to_skip = sc.symbol->GetPrologueByteSize();
+        }
+
+        if (bytes_to_skip == 0 && sc.symbol) {
+          TargetSP target = m_thread.CalculateTarget();
+          const Architecture *arch = target->GetArchitecturePlugin();
+          if (arch) {
+            Address curr_sec_addr;
+            target->GetSectionLoadList().ResolveLoadAddress(curr_addr,
+                                                            curr_sec_addr);
+            bytes_to_skip = arch->GetBytesToSkip(*sc.symbol, curr_sec_addr);
+          }
+        }
+
+        if (bytes_to_skip != 0) {
+          func_start_address.Slide(bytes_to_skip);
+          log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP);
+          LLDB_LOGF(log, "Pushing past prologue ");
+
+          m_sub_plan_sp = m_thread.QueueThreadPlanForRunToAddress(
+              false, func_start_address, true, m_status);
+        }
+      }
+    }
+  }
+
+  if (!m_sub_plan_sp) {
+    m_no_more_plans = true;
+    SetPlanComplete();
+    return true;
+  } else {
+    m_no_more_plans = false;
+    m_sub_plan_sp->SetPrivate(true);
+    return false;
+  }
+}
+
+void ThreadPlanStepInRange::SetAvoidRegexp(const char *name) {
+  auto name_ref = llvm::StringRef::withNullAsEmpty(name);
+  if (m_avoid_regexp_up)
+    *m_avoid_regexp_up = RegularExpression(name_ref);
+  else
+    m_avoid_regexp_up.reset(new RegularExpression(name_ref));
+}
+
+void ThreadPlanStepInRange::SetDefaultFlagValue(uint32_t new_value) {
+  // TODO: Should we test this for sanity?
+  ThreadPlanStepInRange::s_default_flag_values = new_value;
+}
+
+bool ThreadPlanStepInRange::FrameMatchesAvoidCriteria() {
+  StackFrame *frame = GetThread().GetStackFrameAtIndex(0).get();
+
+  // Check the library list first, as that's cheapest:
+  bool libraries_say_avoid = false;
+
+  FileSpecList libraries_to_avoid(GetThread().GetLibrariesToAvoid());
+  size_t num_libraries = libraries_to_avoid.GetSize();
+  if (num_libraries > 0) {
+    SymbolContext sc(frame->GetSymbolContext(eSymbolContextModule));
+    FileSpec frame_library(sc.module_sp->GetFileSpec());
+
+    if (frame_library) {
+      for (size_t i = 0; i < num_libraries; i++) {
+        const FileSpec &file_spec(libraries_to_avoid.GetFileSpecAtIndex(i));
+        if (FileSpec::Match(file_spec, frame_library)) {
+          libraries_say_avoid = true;
+          break;
+        }
+      }
+    }
+  }
+  if (libraries_say_avoid)
+    return true;
+
+  const RegularExpression *avoid_regexp_to_use = m_avoid_regexp_up.get();
+  if (avoid_regexp_to_use == nullptr)
+    avoid_regexp_to_use = GetThread().GetSymbolsToAvoidRegexp();
+
+  if (avoid_regexp_to_use != nullptr) {
+    SymbolContext sc = frame->GetSymbolContext(
+        eSymbolContextFunction | eSymbolContextBlock | eSymbolContextSymbol);
+    if (sc.symbol != nullptr) {
+      const char *frame_function_name =
+          sc.GetFunctionName(Mangled::ePreferDemangledWithoutArguments)
+              .GetCString();
+      if (frame_function_name) {
+        llvm::SmallVector<llvm::StringRef, 2> matches;
+        bool return_value =
+            avoid_regexp_to_use->Execute(frame_function_name, &matches);
+        if (return_value && matches.size() > 1) {
+          std::string match = matches[1].str();
+          LLDB_LOGF(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP),
+                    "Stepping out of function \"%s\" because it matches "
+                    "the avoid regexp \"%s\" - match substring: \"%s\".",
+                    frame_function_name,
+                    avoid_regexp_to_use->GetText().str().c_str(),
+                    match.c_str());
+        }
+        return return_value;
+      }
+    }
+  }
+  return false;
+}
+
+bool ThreadPlanStepInRange::DefaultShouldStopHereCallback(
+    ThreadPlan *current_plan, Flags &flags, FrameComparison operation,
+    Status &status, void *baton) {
+  bool should_stop_here = true;
+  StackFrame *frame = current_plan->GetThread().GetStackFrameAtIndex(0).get();
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+
+  // First see if the ThreadPlanShouldStopHere default implementation thinks we
+  // should get out of here:
+  should_stop_here = ThreadPlanShouldStopHere::DefaultShouldStopHereCallback(
+      current_plan, flags, operation, status, baton);
+  if (!should_stop_here)
+    return false;
+
+  if (should_stop_here && current_plan->GetKind() == eKindStepInRange &&
+      operation == eFrameCompareYounger) {
+    ThreadPlanStepInRange *step_in_range_plan =
+        static_cast<ThreadPlanStepInRange *>(current_plan);
+    if (step_in_range_plan->m_step_into_target) {
+      SymbolContext sc = frame->GetSymbolContext(
+          eSymbolContextFunction | eSymbolContextBlock | eSymbolContextSymbol);
+      if (sc.symbol != nullptr) {
+        // First try an exact match, since that's cheap with ConstStrings.
+        // Then do a strstr compare.
+        if (step_in_range_plan->m_step_into_target == sc.GetFunctionName()) {
+          should_stop_here = true;
+        } else {
+          const char *target_name =
+              step_in_range_plan->m_step_into_target.AsCString();
+          const char *function_name = sc.GetFunctionName().AsCString();
+
+          if (function_name == nullptr)
+            should_stop_here = false;
+          else if (strstr(function_name, target_name) == nullptr)
+            should_stop_here = false;
+        }
+        if (log && !should_stop_here)
+          LLDB_LOGF(log,
+                    "Stepping out of frame %s which did not match step into "
+                    "target %s.",
+                    sc.GetFunctionName().AsCString(),
+                    step_in_range_plan->m_step_into_target.AsCString());
+      }
+    }
+
+    if (should_stop_here) {
+      ThreadPlanStepInRange *step_in_range_plan =
+          static_cast<ThreadPlanStepInRange *>(current_plan);
+      // Don't log the should_step_out here, it's easier to do it in
+      // FrameMatchesAvoidCriteria.
+      should_stop_here = !step_in_range_plan->FrameMatchesAvoidCriteria();
+    }
+  }
+
+  return should_stop_here;
+}
+
+bool ThreadPlanStepInRange::DoPlanExplainsStop(Event *event_ptr) {
+  // We always explain a stop.  Either we've just done a single step, in which
+  // case we'll do our ordinary processing, or we stopped for some reason that
+  // isn't handled by our sub-plans, in which case we want to just stop right
+  // away. In general, we don't want to mark the plan as complete for
+  // unexplained stops. For instance, if you step in to some code with no debug
+  // info, so you step out and in the course of that hit a breakpoint, then you
+  // want to stop & show the user the breakpoint, but not unship the step in
+  // plan, since you still may want to complete that plan when you continue.
+  // This is particularly true when doing "step in to target function."
+  // stepping.
+  //
+  // The only variation is that if we are doing "step by running to next
+  // branch" in which case if we hit our branch breakpoint we don't set the
+  // plan to complete.
+
+  bool return_value = false;
+
+  if (m_virtual_step) {
+    return_value = true;
+  } else {
+    StopInfoSP stop_info_sp = GetPrivateStopInfo();
+    if (stop_info_sp) {
+      StopReason reason = stop_info_sp->GetStopReason();
+
+      if (reason == eStopReasonBreakpoint) {
+        if (NextRangeBreakpointExplainsStop(stop_info_sp)) {
+          return_value = true;
+        }
+      } else if (IsUsuallyUnexplainedStopReason(reason)) {
+        Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+        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;
+      }
+    } else
+      return_value = true;
+  }
+
+  return return_value;
+}
+
+bool ThreadPlanStepInRange::DoWillResume(lldb::StateType resume_state,
+                                         bool current_plan) {
+  m_virtual_step = false;
+  if (resume_state == eStateStepping && current_plan) {
+    // See if we are about to step over a virtual inlined call.
+    bool step_without_resume = m_thread.DecrementCurrentInlinedDepth();
+    if (step_without_resume) {
+      Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+      LLDB_LOGF(log,
+                "ThreadPlanStepInRange::DoWillResume: returning false, "
+                "inline_depth: %d",
+                m_thread.GetCurrentInlinedDepth());
+      SetStopInfo(StopInfo::CreateStopReasonToTrace(m_thread));
+
+      // FIXME: Maybe it would be better to create a InlineStep stop reason, but
+      // then
+      // the whole rest of the world would have to handle that stop reason.
+      m_virtual_step = true;
+    }
+    return !step_without_resume;
+  }
+  return true;
+}
+
+bool ThreadPlanStepInRange::IsVirtualStep() { return m_virtual_step; }