442 lines · cpp
1//===-- ThreadPlanStepOverRange.cpp ---------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "lldb/Target/ThreadPlanStepOverRange.h"10#include "lldb/Symbol/Block.h"11#include "lldb/Symbol/CompileUnit.h"12#include "lldb/Symbol/Function.h"13#include "lldb/Symbol/LineTable.h"14#include "lldb/Target/Language.h"15#include "lldb/Target/Process.h"16#include "lldb/Target/RegisterContext.h"17#include "lldb/Target/Target.h"18#include "lldb/Target/Thread.h"19#include "lldb/Target/ThreadPlanSingleThreadTimeout.h"20#include "lldb/Target/ThreadPlanStepOut.h"21#include "lldb/Target/ThreadPlanStepThrough.h"22#include "lldb/Utility/LLDBLog.h"23#include "lldb/Utility/Log.h"24#include "lldb/Utility/Stream.h"25 26using namespace lldb_private;27using namespace lldb;28 29uint32_t ThreadPlanStepOverRange::s_default_flag_values = 0;30 31// ThreadPlanStepOverRange: Step through a stack range, either stepping over or32// into based on the value of \a type.33 34ThreadPlanStepOverRange::ThreadPlanStepOverRange(35 Thread &thread, const AddressRange &range,36 const SymbolContext &addr_context, lldb::RunMode stop_others,37 LazyBool step_out_avoids_code_without_debug_info)38 : ThreadPlanStepRange(ThreadPlan::eKindStepOverRange,39 "Step range stepping over", thread, range,40 addr_context, stop_others),41 ThreadPlanShouldStopHere(this), TimeoutResumeAll(thread),42 m_first_resume(true), m_run_mode(stop_others) {43 SetFlagsToDefault();44 SetupAvoidNoDebug(step_out_avoids_code_without_debug_info);45}46 47ThreadPlanStepOverRange::~ThreadPlanStepOverRange() = default;48 49void ThreadPlanStepOverRange::GetDescription(Stream *s,50 lldb::DescriptionLevel level) {51 auto PrintFailureIfAny = [&]() {52 if (m_status.Success())53 return;54 s->Printf(" failed (%s)", m_status.AsCString());55 };56 57 if (level == lldb::eDescriptionLevelBrief) {58 s->Printf("step over");59 PrintFailureIfAny();60 return;61 }62 63 s->Printf("Stepping over");64 bool printed_line_info = false;65 if (m_addr_context.line_entry.IsValid()) {66 s->Printf(" line ");67 m_addr_context.line_entry.DumpStopContext(s, false);68 printed_line_info = true;69 }70 71 if (!printed_line_info || level == eDescriptionLevelVerbose) {72 s->Printf(" using ranges: ");73 DumpRanges(s);74 }75 76 PrintFailureIfAny();77 78 s->PutChar('.');79}80 81void ThreadPlanStepOverRange::SetupAvoidNoDebug(82 LazyBool step_out_avoids_code_without_debug_info) {83 bool avoid_nodebug = true;84 switch (step_out_avoids_code_without_debug_info) {85 case eLazyBoolYes:86 avoid_nodebug = true;87 break;88 case eLazyBoolNo:89 avoid_nodebug = false;90 break;91 case eLazyBoolCalculate:92 avoid_nodebug = GetThread().GetStepOutAvoidsNoDebug();93 break;94 }95 if (avoid_nodebug)96 GetFlags().Set(ThreadPlanShouldStopHere::eStepOutAvoidNoDebug);97 else98 GetFlags().Clear(ThreadPlanShouldStopHere::eStepOutAvoidNoDebug);99 // Step Over plans should always avoid no-debug on step in. Seems like you100 // shouldn't have to say this, but a tail call looks more like a step in that101 // a step out, so we want to catch this case.102 GetFlags().Set(ThreadPlanShouldStopHere::eStepInAvoidNoDebug);103}104 105bool ThreadPlanStepOverRange::IsEquivalentContext(106 const SymbolContext &context) {107 if (Language *language = Language::FindPlugin(context.GetLanguage()))108 if (std::optional<bool> maybe_equivalent =109 language->AreEqualForFrameComparison(context, m_addr_context))110 return *maybe_equivalent;111 // Match as much as is specified in the m_addr_context: This is a fairly112 // loose sanity check. Note, sometimes the target doesn't get filled in so I113 // left out the target check. And sometimes the module comes in as the .o114 // file from the inlined range, so I left that out too...115 if (m_addr_context.comp_unit) {116 if (m_addr_context.comp_unit != context.comp_unit)117 return false;118 if (m_addr_context.function) {119 if (m_addr_context.function != context.function)120 return false;121 // It is okay to return to a different block of a straight function, we122 // only have to be more careful if returning from one inlined block to123 // another.124 if (m_addr_context.block->GetInlinedFunctionInfo() == nullptr &&125 context.block->GetInlinedFunctionInfo() == nullptr)126 return true;127 return m_addr_context.block == context.block;128 }129 }130 // Fall back to symbol if we have no decision from comp_unit/function/block.131 return m_addr_context.symbol && m_addr_context.symbol == context.symbol;132}133 134void ThreadPlanStepOverRange::SetStopOthers(bool stop_others) {135 if (!stop_others)136 m_stop_others = RunMode::eAllThreads;137}138 139bool ThreadPlanStepOverRange::ShouldStop(Event *event_ptr) {140 Log *log = GetLog(LLDBLog::Step);141 Thread &thread = GetThread();142 143 if (log) {144 StreamString s;145 DumpAddress(s.AsRawOstream(), thread.GetRegisterContext()->GetPC(),146 GetTarget().GetArchitecture().GetAddressByteSize());147 LLDB_LOGF(log, "ThreadPlanStepOverRange reached %s.", s.GetData());148 }149 ClearNextBranchBreakpointExplainedStop();150 151 // If we're out of the range but in the same frame or in our caller's frame152 // then we should stop. When stepping out we only stop others if we are153 // forcing running one thread.154 bool stop_others = (m_stop_others == lldb::eOnlyThisThread);155 ThreadPlanSP new_plan_sp;156 FrameComparison frame_order = CompareCurrentFrameToStartFrame();157 LLDB_LOGF(log, "ThreadPlanStepOverRange compare frame result: %d.",158 frame_order);159 160 if (frame_order == eFrameCompareOlder) {161 // If we're in an older frame then we should stop.162 //163 // A caveat to this is if we think the frame is older but we're actually in164 // a trampoline.165 // I'm going to make the assumption that you wouldn't RETURN to a166 // trampoline. So if we are in a trampoline we think the frame is older167 // because the trampoline confused the backtracer. As below, we step168 // through first, and then try to figure out how to get back out again.169 170 new_plan_sp = thread.QueueThreadPlanForStepThrough(m_stack_id, false,171 stop_others, m_status);172 173 if (new_plan_sp && log)174 LLDB_LOGF(log,175 "Thought I stepped out, but in fact arrived at a trampoline.");176 } else if (frame_order == eFrameCompareYounger) {177 // Make sure we really are in a new frame. Do that by unwinding and seeing178 // if the start function really is our start function...179 for (uint32_t i = 1;; ++i) {180 StackFrameSP older_frame_sp = thread.GetStackFrameAtIndex(i);181 if (!older_frame_sp) {182 // We can't unwind the next frame we should just get out of here &183 // stop...184 break;185 }186 187 const SymbolContext &older_context =188 older_frame_sp->GetSymbolContext(eSymbolContextEverything);189 if (IsEquivalentContext(older_context)) {190 // If we have the next-branch-breakpoint in the range, we can just191 // rely on that breakpoint to trigger once we return to the range.192 if (m_next_branch_bp_sp)193 return false;194 new_plan_sp = thread.QueueThreadPlanForStepOutNoShouldStop(195 false, nullptr, true, stop_others, eVoteNo, eVoteNoOpinion, 0,196 m_status, true);197 break;198 } else {199 new_plan_sp = thread.QueueThreadPlanForStepThrough(200 m_stack_id, false, stop_others, m_status);201 // If we found a way through, then we should stop recursing.202 if (new_plan_sp)203 break;204 }205 }206 } else {207 // If we're still in the range, keep going.208 if (InRange()) {209 SetNextBranchBreakpoint();210 return false;211 }212 213 if (!InSymbol()) {214 // This one is a little tricky. Sometimes we may be in a stub or215 // something similar, in which case we need to get out of there. But if216 // we are in a stub then it's likely going to be hard to get out from217 // here. It is probably easiest to step into the stub, and then it will218 // be straight-forward to step out.219 new_plan_sp = thread.QueueThreadPlanForStepThrough(m_stack_id, false, 220 stop_others, m_status);221 } else {222 // The current clang (at least through 424) doesn't always get the223 // address range for the DW_TAG_inlined_subroutines right, so that when224 // you leave the inlined range the line table says you are still in the225 // source file of the inlining function. This is bad, because now you226 // are missing the stack frame for the function containing the inlining,227 // and if you sensibly do "finish" to get out of this function you will228 // instead exit the containing function. To work around this, we check229 // whether we are still in the source file we started in, and if not230 // assume it is an error, and push a plan to get us out of this line and231 // back to the containing file.232 233 if (m_addr_context.line_entry.IsValid()) {234 SymbolContext sc;235 StackFrameSP frame_sp = thread.GetStackFrameAtIndex(0);236 sc = frame_sp->GetSymbolContext(eSymbolContextEverything);237 if (sc.line_entry.IsValid()) {238 if (!sc.line_entry.original_file_sp->Equal(239 *m_addr_context.line_entry.original_file_sp,240 SupportFile::eEqualFileSpecAndChecksumIfSet) &&241 sc.comp_unit == m_addr_context.comp_unit &&242 sc.function == m_addr_context.function) {243 // Okay, find the next occurrence of this file in the line table:244 LineTable *line_table = m_addr_context.comp_unit->GetLineTable();245 if (line_table) {246 Address cur_address = frame_sp->GetFrameCodeAddress();247 uint32_t entry_idx;248 LineEntry line_entry;249 if (line_table->FindLineEntryByAddress(cur_address, line_entry,250 &entry_idx)) {251 LineEntry next_line_entry;252 bool step_past_remaining_inline = false;253 if (entry_idx > 0) {254 // We require the previous line entry and the current line255 // entry come from the same file. The other requirement is256 // that the previous line table entry be part of an inlined257 // block, we don't want to step past cases where people have258 // inlined some code fragment by using #include <source-259 // fragment.c> directly.260 LineEntry prev_line_entry;261 if (line_table->GetLineEntryAtIndex(entry_idx - 1,262 prev_line_entry) &&263 prev_line_entry.original_file_sp->Equal(264 *line_entry.original_file_sp,265 SupportFile::eEqualFileSpecAndChecksumIfSet)) {266 SymbolContext prev_sc;267 Address prev_address =268 prev_line_entry.range.GetBaseAddress();269 prev_address.CalculateSymbolContext(&prev_sc);270 if (prev_sc.block) {271 Block *inlined_block =272 prev_sc.block->GetContainingInlinedBlock();273 if (inlined_block) {274 AddressRange inline_range;275 inlined_block->GetRangeContainingAddress(prev_address,276 inline_range);277 if (!inline_range.ContainsFileAddress(cur_address)) {278 279 step_past_remaining_inline = true;280 }281 }282 }283 }284 }285 286 if (step_past_remaining_inline) {287 uint32_t look_ahead_step = 1;288 while (line_table->GetLineEntryAtIndex(289 entry_idx + look_ahead_step, next_line_entry)) {290 // Make sure we haven't wandered out of the function we291 // started from...292 Address next_line_address =293 next_line_entry.range.GetBaseAddress();294 Function *next_line_function =295 next_line_address.CalculateSymbolContextFunction();296 if (next_line_function != m_addr_context.function)297 break;298 299 if (next_line_entry.original_file_sp->Equal(300 *m_addr_context.line_entry.original_file_sp,301 SupportFile::eEqualFileSpecAndChecksumIfSet)) {302 const bool abort_other_plans = false;303 const RunMode stop_other_threads = RunMode::eAllThreads;304 lldb::addr_t cur_pc = thread.GetStackFrameAtIndex(0)305 ->GetRegisterContext()306 ->GetPC();307 AddressRange step_range(308 cur_pc,309 next_line_address.GetLoadAddress(&GetTarget()) -310 cur_pc);311 312 new_plan_sp = thread.QueueThreadPlanForStepOverRange(313 abort_other_plans, step_range, sc, stop_other_threads,314 m_status);315 break;316 }317 look_ahead_step++;318 }319 }320 }321 }322 }323 }324 }325 }326 }327 328 // If we get to this point, we're not going to use a previously set "next329 // branch" breakpoint, so delete it:330 ClearNextBranchBreakpoint();331 332 // If we haven't figured out something to do yet, then ask the ShouldStopHere333 // callback:334 if (!new_plan_sp) {335 new_plan_sp = CheckShouldStopHereAndQueueStepOut(frame_order, m_status);336 }337 338 if (!new_plan_sp)339 m_no_more_plans = true;340 else {341 // Any new plan will be an implementation plan, so mark it private:342 new_plan_sp->SetPrivate(true);343 m_no_more_plans = false;344 }345 346 if (!new_plan_sp) {347 // For efficiencies sake, we know we're done here so we don't have to do348 // this calculation again in MischiefManaged.349 SetPlanComplete(m_status.Success());350 return true;351 } else352 return false;353}354 355void ThreadPlanStepOverRange::DidPush() {356 ThreadPlanStepRange::DidPush();357 if (m_run_mode == lldb::eOnlyThisThread && IsControllingPlan())358 PushNewTimeout();359}360 361bool ThreadPlanStepOverRange::DoPlanExplainsStop(Event *event_ptr) {362 // For crashes, breakpoint hits, signals, etc, let the base plan (or some363 // plan above us) handle the stop. That way the user can see the stop, step364 // around, and then when they are done, continue and have their step365 // complete. The exception is if we've hit our "run to next branch"366 // breakpoint. Note, unlike the step in range plan, we don't mark ourselves367 // complete if we hit an unexplained breakpoint/crash.368 369 Log *log = GetLog(LLDBLog::Step);370 StopInfoSP stop_info_sp = GetPrivateStopInfo();371 bool return_value;372 373 if (stop_info_sp) {374 StopReason reason = stop_info_sp->GetStopReason();375 376 if (reason == eStopReasonTrace) {377 return_value = true;378 } else if (reason == eStopReasonBreakpoint) {379 return_value = NextRangeBreakpointExplainsStop(stop_info_sp);380 } else {381 if (log)382 log->PutCString("ThreadPlanStepOverRange got asked if it explains the "383 "stop for some reason other than step.");384 return_value = false;385 }386 } else387 return_value = true;388 389 return return_value;390}391 392bool ThreadPlanStepOverRange::DoWillResume(lldb::StateType resume_state,393 bool current_plan) {394 if (resume_state != eStateSuspended && m_first_resume) {395 m_first_resume = false;396 if (resume_state == eStateStepping && current_plan) {397 Thread &thread = GetThread();398 // See if we are about to step over an inlined call in the middle of the399 // inlined stack, if so figure out its extents and reset our range to400 // step over that.401 bool in_inlined_stack = thread.DecrementCurrentInlinedDepth();402 if (in_inlined_stack) {403 Log *log = GetLog(LLDBLog::Step);404 LLDB_LOGF(log,405 "ThreadPlanStepOverRange::DoWillResume: adjusting range to "406 "the frame at inlined depth %d.",407 thread.GetCurrentInlinedDepth());408 StackFrameSP stack_sp = thread.GetStackFrameAtIndex(0);409 if (stack_sp) {410 Block *frame_block = stack_sp->GetFrameBlock();411 lldb::addr_t curr_pc = thread.GetRegisterContext()->GetPC();412 AddressRange my_range;413 if (frame_block->GetRangeContainingLoadAddress(414 curr_pc, m_process.GetTarget(), my_range)) {415 m_address_ranges.clear();416 m_address_ranges.push_back(my_range);417 if (log) {418 StreamString s;419 const InlineFunctionInfo *inline_info =420 frame_block->GetInlinedFunctionInfo();421 const char *name;422 if (inline_info)423 name = inline_info->GetName().AsCString();424 else425 name = "<unknown-notinlined>";426 427 s.Printf(428 "Stepping over inlined function \"%s\" in inlined stack: ",429 name);430 DumpRanges(&s);431 log->PutString(s.GetString());432 }433 }434 }435 }436 }437 }438 if (m_run_mode == lldb::eOnlyThisThread && IsControllingPlan())439 ResumeWithTimeout();440 return true;441}442