500 lines · cpp
1//===-- ThreadPlanStepInRange.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/ThreadPlanStepInRange.h"10#include "lldb/Core/Architecture.h"11#include "lldb/Core/Module.h"12#include "lldb/Symbol/Function.h"13#include "lldb/Symbol/Symbol.h"14#include "lldb/Target/Process.h"15#include "lldb/Target/RegisterContext.h"16#include "lldb/Target/SectionLoadList.h"17#include "lldb/Target/Target.h"18#include "lldb/Target/Thread.h"19#include "lldb/Target/ThreadPlanStepOut.h"20#include "lldb/Target/ThreadPlanStepThrough.h"21#include "lldb/Utility/LLDBLog.h"22#include "lldb/Utility/Log.h"23#include "lldb/Utility/RegularExpression.h"24#include "lldb/Utility/Stream.h"25 26using namespace lldb;27using namespace lldb_private;28 29uint32_t ThreadPlanStepInRange::s_default_flag_values =30 ThreadPlanShouldStopHere::eStepInAvoidNoDebug |31 ThreadPlanShouldStopHere::eStepOutPastThunks;32 33// ThreadPlanStepInRange: Step through a stack range, either stepping over or34// into based on the value of \a type.35 36ThreadPlanStepInRange::ThreadPlanStepInRange(37 Thread &thread, const AddressRange &range,38 const SymbolContext &addr_context, const char *step_into_target,39 lldb::RunMode stop_others, LazyBool step_in_avoids_code_without_debug_info,40 LazyBool step_out_avoids_code_without_debug_info)41 : ThreadPlanStepRange(ThreadPlan::eKindStepInRange,42 "Step Range stepping in", thread, range, addr_context,43 stop_others),44 ThreadPlanShouldStopHere(this), m_step_past_prologue(true),45 m_virtual_step(eLazyBoolCalculate), m_step_into_target(step_into_target) {46 SetCallbacks();47 SetFlagsToDefault();48 SetupAvoidNoDebug(step_in_avoids_code_without_debug_info,49 step_out_avoids_code_without_debug_info);50}51 52ThreadPlanStepInRange::~ThreadPlanStepInRange() = default;53 54void ThreadPlanStepInRange::SetupAvoidNoDebug(55 LazyBool step_in_avoids_code_without_debug_info,56 LazyBool step_out_avoids_code_without_debug_info) {57 bool avoid_nodebug = true;58 Thread &thread = GetThread();59 switch (step_in_avoids_code_without_debug_info) {60 case eLazyBoolYes:61 avoid_nodebug = true;62 break;63 case eLazyBoolNo:64 avoid_nodebug = false;65 break;66 case eLazyBoolCalculate:67 avoid_nodebug = thread.GetStepInAvoidsNoDebug();68 break;69 }70 if (avoid_nodebug)71 GetFlags().Set(ThreadPlanShouldStopHere::eStepInAvoidNoDebug);72 else73 GetFlags().Clear(ThreadPlanShouldStopHere::eStepInAvoidNoDebug);74 75 switch (step_out_avoids_code_without_debug_info) {76 case eLazyBoolYes:77 avoid_nodebug = true;78 break;79 case eLazyBoolNo:80 avoid_nodebug = false;81 break;82 case eLazyBoolCalculate:83 avoid_nodebug = thread.GetStepOutAvoidsNoDebug();84 break;85 }86 if (avoid_nodebug)87 GetFlags().Set(ThreadPlanShouldStopHere::eStepOutAvoidNoDebug);88 else89 GetFlags().Clear(ThreadPlanShouldStopHere::eStepOutAvoidNoDebug);90}91 92void ThreadPlanStepInRange::GetDescription(Stream *s,93 lldb::DescriptionLevel level) {94 95 auto PrintFailureIfAny = [&]() {96 if (m_status.Success())97 return;98 s->Printf(" failed (%s)", m_status.AsCString());99 };100 101 if (level == lldb::eDescriptionLevelBrief) {102 s->Printf("step in");103 PrintFailureIfAny();104 return;105 }106 107 s->Printf("Stepping in");108 bool printed_line_info = false;109 if (m_addr_context.line_entry.IsValid()) {110 s->Printf(" through line ");111 m_addr_context.line_entry.DumpStopContext(s, false);112 printed_line_info = true;113 }114 115 const char *step_into_target = m_step_into_target.AsCString();116 if (step_into_target && step_into_target[0] != '\0')117 s->Printf(" targeting %s", m_step_into_target.AsCString());118 119 if (!printed_line_info || level == eDescriptionLevelVerbose) {120 s->Printf(" using ranges:");121 DumpRanges(s);122 }123 124 PrintFailureIfAny();125 126 s->PutChar('.');127}128 129bool ThreadPlanStepInRange::ShouldStop(Event *event_ptr) {130 Log *log = GetLog(LLDBLog::Step);131 132 if (log) {133 StreamString s;134 DumpAddress(s.AsRawOstream(), GetThread().GetRegisterContext()->GetPC(),135 GetTarget().GetArchitecture().GetAddressByteSize());136 LLDB_LOGF(log, "ThreadPlanStepInRange reached %s.", s.GetData());137 }138 ClearNextBranchBreakpointExplainedStop();139 140 if (IsPlanComplete())141 return true;142 143 m_no_more_plans = false;144 if (m_sub_plan_sp && m_sub_plan_sp->IsPlanComplete()) {145 if (!m_sub_plan_sp->PlanSucceeded()) {146 SetPlanComplete();147 m_no_more_plans = true;148 return true;149 } else150 m_sub_plan_sp.reset();151 }152 153 if (m_virtual_step == eLazyBoolYes) {154 // If we've just completed a virtual step, all we need to do is check for a155 // ShouldStopHere plan, and otherwise we're done.156 // FIXME - This can be both a step in and a step out. Probably should157 // record which in the m_virtual_step.158 m_sub_plan_sp =159 CheckShouldStopHereAndQueueStepOut(eFrameCompareYounger, m_status);160 } else {161 // Stepping through should be done running other threads in general, since162 // we're setting a breakpoint and continuing. So only stop others if we163 // are explicitly told to do so.164 165 bool stop_others = (m_stop_others == lldb::eOnlyThisThread);166 167 FrameComparison frame_order = CompareCurrentFrameToStartFrame();168 169 Thread &thread = GetThread();170 if (frame_order == eFrameCompareOlder ||171 frame_order == eFrameCompareSameParent) {172 // If we're in an older frame then we should stop.173 //174 // A caveat to this is if we think the frame is older but we're actually175 // in a trampoline.176 // I'm going to make the assumption that you wouldn't RETURN to a177 // trampoline. So if we are in a trampoline we think the frame is older178 // because the trampoline confused the backtracer.179 m_sub_plan_sp = thread.QueueThreadPlanForStepThrough(180 m_stack_id, false, stop_others, m_status);181 if (!m_sub_plan_sp) {182 // Otherwise check the ShouldStopHere for step out:183 m_sub_plan_sp =184 CheckShouldStopHereAndQueueStepOut(frame_order, m_status);185 if (log) {186 if (m_sub_plan_sp)187 LLDB_LOGF(log,188 "ShouldStopHere found plan to step out of this frame.");189 else190 LLDB_LOGF(log, "ShouldStopHere no plan to step out of this frame.");191 }192 } else if (log) {193 LLDB_LOGF(194 log, "Thought I stepped out, but in fact arrived at a trampoline.");195 }196 } else if (frame_order == eFrameCompareEqual && InSymbol()) {197 // If we are not in a place we should step through, we're done. One198 // tricky bit here is that some stubs don't push a frame, so we have to199 // check both the case of a frame that is younger, or the same as this200 // frame. However, if the frame is the same, and we are still in the201 // symbol we started in, the we don't need to do this. This first check202 // isn't strictly necessary, but it is more efficient.203 204 // If we're still in the range, keep going, either by running to the next205 // branch breakpoint, or by stepping.206 if (InRange()) {207 SetNextBranchBreakpoint();208 return false;209 }210 211 SetPlanComplete();212 m_no_more_plans = true;213 return true;214 }215 216 // If we get to this point, we're not going to use a previously set "next217 // branch" breakpoint, so delete it:218 ClearNextBranchBreakpoint();219 220 // We may have set the plan up above in the FrameIsOlder section:221 222 if (!m_sub_plan_sp)223 m_sub_plan_sp = thread.QueueThreadPlanForStepThrough(224 m_stack_id, false, stop_others, m_status);225 226 if (log) {227 if (m_sub_plan_sp)228 LLDB_LOGF(log, "Found a step through plan: %s",229 m_sub_plan_sp->GetName());230 else231 LLDB_LOGF(log, "No step through plan found.");232 }233 234 // If not, give the "should_stop" callback a chance to push a plan to get235 // us out of here. But only do that if we actually have stepped in.236 if (!m_sub_plan_sp && frame_order == eFrameCompareYounger)237 m_sub_plan_sp = CheckShouldStopHereAndQueueStepOut(frame_order, m_status);238 239 // If we've stepped in and we are going to stop here, check to see if we240 // were asked to run past the prologue, and if so do that.241 242 if (!m_sub_plan_sp && frame_order == eFrameCompareYounger &&243 m_step_past_prologue) {244 lldb::StackFrameSP curr_frame = thread.GetStackFrameAtIndex(0);245 if (curr_frame) {246 size_t bytes_to_skip = 0;247 lldb::addr_t curr_addr = thread.GetRegisterContext()->GetPC();248 Address func_start_address;249 250 SymbolContext sc = curr_frame->GetSymbolContext(eSymbolContextFunction |251 eSymbolContextSymbol);252 253 if (sc.function) {254 func_start_address = sc.function->GetAddress();255 if (curr_addr == func_start_address.GetLoadAddress(&GetTarget()))256 bytes_to_skip = sc.function->GetPrologueByteSize();257 } else if (sc.symbol) {258 func_start_address = sc.symbol->GetAddress();259 if (curr_addr == func_start_address.GetLoadAddress(&GetTarget()))260 bytes_to_skip = sc.symbol->GetPrologueByteSize();261 }262 263 if (bytes_to_skip == 0 && sc.symbol) {264 const Architecture *arch = GetTarget().GetArchitecturePlugin();265 if (arch) {266 Address curr_sec_addr;267 GetTarget().ResolveLoadAddress(curr_addr, curr_sec_addr);268 bytes_to_skip = arch->GetBytesToSkip(*sc.symbol, curr_sec_addr);269 }270 }271 272 if (bytes_to_skip != 0) {273 func_start_address.Slide(bytes_to_skip);274 log = GetLog(LLDBLog::Step);275 LLDB_LOGF(log, "Pushing past prologue ");276 277 m_sub_plan_sp = thread.QueueThreadPlanForRunToAddress(278 false, func_start_address, true, m_status);279 }280 }281 }282 }283 284 if (!m_sub_plan_sp) {285 m_no_more_plans = true;286 SetPlanComplete();287 return true;288 } else {289 m_no_more_plans = false;290 m_sub_plan_sp->SetPrivate(true);291 return false;292 }293}294 295void ThreadPlanStepInRange::SetAvoidRegexp(const char *name) {296 if (m_avoid_regexp_up)297 *m_avoid_regexp_up = RegularExpression(name);298 else299 m_avoid_regexp_up = std::make_unique<RegularExpression>(name);300}301 302void ThreadPlanStepInRange::SetDefaultFlagValue(uint32_t new_value) {303 // TODO: Should we test this for sanity?304 ThreadPlanStepInRange::s_default_flag_values = new_value;305}306 307bool ThreadPlanStepInRange::FrameMatchesAvoidCriteria() {308 StackFrame *frame = GetThread().GetStackFrameAtIndex(0).get();309 310 // Check the library list first, as that's cheapest:311 bool libraries_say_avoid = false;312 313 FileSpecList libraries_to_avoid(GetThread().GetLibrariesToAvoid());314 size_t num_libraries = libraries_to_avoid.GetSize();315 if (num_libraries > 0) {316 SymbolContext sc(frame->GetSymbolContext(eSymbolContextModule));317 FileSpec frame_library(sc.module_sp->GetFileSpec());318 319 if (frame_library) {320 for (size_t i = 0; i < num_libraries; i++) {321 const FileSpec &file_spec(libraries_to_avoid.GetFileSpecAtIndex(i));322 if (FileSpec::Match(file_spec, frame_library)) {323 libraries_say_avoid = true;324 break;325 }326 }327 }328 }329 if (libraries_say_avoid)330 return true;331 332 const RegularExpression *avoid_regexp_to_use = m_avoid_regexp_up.get();333 if (avoid_regexp_to_use == nullptr)334 avoid_regexp_to_use = GetThread().GetSymbolsToAvoidRegexp();335 336 if (avoid_regexp_to_use != nullptr) {337 SymbolContext sc = frame->GetSymbolContext(338 eSymbolContextFunction | eSymbolContextBlock | eSymbolContextSymbol);339 if (sc.symbol != nullptr) {340 const char *frame_function_name =341 sc.GetFunctionName(Mangled::ePreferDemangledWithoutArguments)342 .GetCString();343 if (frame_function_name) {344 bool return_value = avoid_regexp_to_use->Execute(frame_function_name);345 if (return_value) {346 LLDB_LOGF(GetLog(LLDBLog::Step),347 "Stepping out of function \"%s\" because it matches the "348 "avoid regexp \"%s\".",349 frame_function_name,350 avoid_regexp_to_use->GetText().str().c_str());351 }352 return return_value;353 }354 }355 }356 return false;357}358 359bool ThreadPlanStepInRange::DefaultShouldStopHereCallback(360 ThreadPlan *current_plan, Flags &flags, FrameComparison operation,361 Status &status, void *baton) {362 bool should_stop_here = true;363 StackFrame *frame = current_plan->GetThread().GetStackFrameAtIndex(0).get();364 Log *log = GetLog(LLDBLog::Step);365 366 // First see if the ThreadPlanShouldStopHere default implementation thinks we367 // should get out of here:368 should_stop_here = ThreadPlanShouldStopHere::DefaultShouldStopHereCallback(369 current_plan, flags, operation, status, baton);370 if (!should_stop_here)371 return false;372 373 if (current_plan->GetKind() == eKindStepInRange &&374 operation == eFrameCompareYounger) {375 ThreadPlanStepInRange *step_in_range_plan =376 static_cast<ThreadPlanStepInRange *>(current_plan);377 if (step_in_range_plan->m_step_into_target) {378 SymbolContext sc = frame->GetSymbolContext(379 eSymbolContextFunction | eSymbolContextBlock | eSymbolContextSymbol);380 if (sc.symbol != nullptr) {381 // First try an exact match, since that's cheap with ConstStrings.382 // Then do a strstr compare.383 if (step_in_range_plan->m_step_into_target == sc.GetFunctionName()) {384 should_stop_here = true;385 } else {386 const char *target_name =387 step_in_range_plan->m_step_into_target.AsCString();388 const char *function_name = sc.GetFunctionName().AsCString();389 390 if (function_name == nullptr)391 should_stop_here = false;392 else if (strstr(function_name, target_name) == nullptr)393 should_stop_here = false;394 }395 if (log && !should_stop_here)396 LLDB_LOGF(log,397 "Stepping out of frame %s which did not match step into "398 "target %s.",399 sc.GetFunctionName().AsCString(),400 step_in_range_plan->m_step_into_target.AsCString());401 }402 }403 404 if (should_stop_here) {405 ThreadPlanStepInRange *step_in_range_plan =406 static_cast<ThreadPlanStepInRange *>(current_plan);407 // Don't log the should_step_out here, it's easier to do it in408 // FrameMatchesAvoidCriteria.409 should_stop_here = !step_in_range_plan->FrameMatchesAvoidCriteria();410 }411 }412 413 return should_stop_here;414}415 416bool ThreadPlanStepInRange::DoPlanExplainsStop(Event *event_ptr) {417 // We always explain a stop. Either we've just done a single step, in which418 // case we'll do our ordinary processing, or we stopped for some reason that419 // isn't handled by our sub-plans, in which case we want to just stop right420 // away. In general, we don't want to mark the plan as complete for421 // unexplained stops. For instance, if you step in to some code with no debug422 // info, so you step out and in the course of that hit a breakpoint, then you423 // want to stop & show the user the breakpoint, but not unship the step in424 // plan, since you still may want to complete that plan when you continue.425 // This is particularly true when doing "step in to target function."426 // stepping.427 //428 // The only variation is that if we are doing "step by running to next429 // branch" in which case if we hit our branch breakpoint we don't set the430 // plan to complete.431 432 bool return_value = false;433 434 if (m_virtual_step == eLazyBoolYes) {435 return_value = true;436 } else {437 StopInfoSP stop_info_sp = GetPrivateStopInfo();438 if (stop_info_sp) {439 StopReason reason = stop_info_sp->GetStopReason();440 441 if (reason == eStopReasonBreakpoint) {442 if (NextRangeBreakpointExplainsStop(stop_info_sp)) {443 return_value = true;444 }445 } else if (IsUsuallyUnexplainedStopReason(reason)) {446 Log *log = GetLog(LLDBLog::Step);447 if (log)448 log->PutCString("ThreadPlanStepInRange got asked if it explains the "449 "stop for some reason other than step.");450 return_value = false;451 } else {452 return_value = true;453 }454 } else455 return_value = true;456 }457 458 return return_value;459}460 461bool ThreadPlanStepInRange::DoWillResume(lldb::StateType resume_state,462 bool current_plan) {463 m_virtual_step = eLazyBoolCalculate;464 if (resume_state == eStateStepping && current_plan) {465 Thread &thread = GetThread();466 // See if we are about to step over a virtual inlined call.467 // But if we already know we're virtual stepping, don't decrement the468 // inlined depth again...469 470 bool step_without_resume = thread.DecrementCurrentInlinedDepth();471 if (step_without_resume) {472 Log *log = GetLog(LLDBLog::Step);473 LLDB_LOGF(log,474 "ThreadPlanStepInRange::DoWillResume: returning false, "475 "inline_depth: %d",476 thread.GetCurrentInlinedDepth());477 SetStopInfo(StopInfo::CreateStopReasonToTrace(thread));478 479 // FIXME: Maybe it would be better to create a InlineStep stop reason, but480 // then481 // the whole rest of the world would have to handle that stop reason.482 m_virtual_step = eLazyBoolYes;483 }484 return !step_without_resume;485 }486 return true;487}488 489bool ThreadPlanStepInRange::IsVirtualStep() {490 if (m_virtual_step == eLazyBoolCalculate) {491 Thread &thread = GetThread();492 uint32_t cur_inline_depth = thread.GetCurrentInlinedDepth();493 if (cur_inline_depth == UINT32_MAX || cur_inline_depth == 0)494 m_virtual_step = eLazyBoolNo;495 else496 m_virtual_step = eLazyBoolYes;497 }498 return m_virtual_step == eLazyBoolYes;499}500