LLDB mainline
ThreadPlanStepOverRange.cpp
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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-exception
6//
7//===----------------------------------------------------------------------===//
8
10#include "lldb/Symbol/Block.h"
14#include "lldb/Target/Process.h"
16#include "lldb/Target/Target.h"
17#include "lldb/Target/Thread.h"
21#include "lldb/Utility/Log.h"
22#include "lldb/Utility/Stream.h"
23
24using namespace lldb_private;
25using namespace lldb;
26
28
29// ThreadPlanStepOverRange: Step through a stack range, either stepping over or
30// into based on the value of \a type.
31
33 Thread &thread, const AddressRange &range,
34 const SymbolContext &addr_context, lldb::RunMode stop_others,
35 LazyBool step_out_avoids_code_without_debug_info)
36 : ThreadPlanStepRange(ThreadPlan::eKindStepOverRange,
37 "Step range stepping over", thread, range,
38 addr_context, stop_others),
39 ThreadPlanShouldStopHere(this), m_first_resume(true) {
41 SetupAvoidNoDebug(step_out_avoids_code_without_debug_info);
42}
43
45
48 auto PrintFailureIfAny = [&]() {
49 if (m_status.Success())
50 return;
51 s->Printf(" failed (%s)", m_status.AsCString());
52 };
53
54 if (level == lldb::eDescriptionLevelBrief) {
55 s->Printf("step over");
56 PrintFailureIfAny();
57 return;
58 }
59
60 s->Printf("Stepping over");
61 bool printed_line_info = false;
63 s->Printf(" line ");
65 printed_line_info = true;
66 }
67
68 if (!printed_line_info || level == eDescriptionLevelVerbose) {
69 s->Printf(" using ranges: ");
70 DumpRanges(s);
71 }
72
73 PrintFailureIfAny();
74
75 s->PutChar('.');
76}
77
79 LazyBool step_out_avoids_code_without_debug_info) {
80 bool avoid_nodebug = true;
81 switch (step_out_avoids_code_without_debug_info) {
82 case eLazyBoolYes:
83 avoid_nodebug = true;
84 break;
85 case eLazyBoolNo:
86 avoid_nodebug = false;
87 break;
89 avoid_nodebug = GetThread().GetStepOutAvoidsNoDebug();
90 break;
91 }
92 if (avoid_nodebug)
94 else
96 // Step Over plans should always avoid no-debug on step in. Seems like you
97 // shouldn't have to say this, but a tail call looks more like a step in that
98 // a step out, so we want to catch this case.
100}
101
103 const SymbolContext &context) {
104 // Match as much as is specified in the m_addr_context: This is a fairly
105 // loose sanity check. Note, sometimes the target doesn't get filled in so I
106 // left out the target check. And sometimes the module comes in as the .o
107 // file from the inlined range, so I left that out too...
109 if (m_addr_context.comp_unit != context.comp_unit)
110 return false;
112 if (m_addr_context.function != context.function)
113 return false;
114 // It is okay to return to a different block of a straight function, we
115 // only have to be more careful if returning from one inlined block to
116 // another.
117 if (m_addr_context.block->GetInlinedFunctionInfo() == nullptr &&
118 context.block->GetInlinedFunctionInfo() == nullptr)
119 return true;
120 return m_addr_context.block == context.block;
121 }
122 }
123 // Fall back to symbol if we have no decision from comp_unit/function/block.
124 return m_addr_context.symbol && m_addr_context.symbol == context.symbol;
125}
126
128 Log *log = GetLog(LLDBLog::Step);
129 Thread &thread = GetThread();
130
131 if (log) {
132 StreamString s;
133 DumpAddress(s.AsRawOstream(), thread.GetRegisterContext()->GetPC(),
134 GetTarget().GetArchitecture().GetAddressByteSize());
135 LLDB_LOGF(log, "ThreadPlanStepOverRange reached %s.", s.GetData());
136 }
137
138 // If we're out of the range but in the same frame or in our caller's frame
139 // then we should stop. When stepping out we only stop others if we are
140 // forcing running one thread.
141 bool stop_others = (m_stop_others == lldb::eOnlyThisThread);
142 ThreadPlanSP new_plan_sp;
144
145 if (frame_order == eFrameCompareOlder) {
146 // If we're in an older frame then we should stop.
147 //
148 // A caveat to this is if we think the frame is older but we're actually in
149 // a trampoline.
150 // I'm going to make the assumption that you wouldn't RETURN to a
151 // trampoline. So if we are in a trampoline we think the frame is older
152 // because the trampoline confused the backtracer. As below, we step
153 // through first, and then try to figure out how to get back out again.
154
155 new_plan_sp = thread.QueueThreadPlanForStepThrough(m_stack_id, false,
156 stop_others, m_status);
157
158 if (new_plan_sp && log)
159 LLDB_LOGF(log,
160 "Thought I stepped out, but in fact arrived at a trampoline.");
161 } else if (frame_order == eFrameCompareYounger) {
162 // Make sure we really are in a new frame. Do that by unwinding and seeing
163 // if the start function really is our start function...
164 for (uint32_t i = 1;; ++i) {
165 StackFrameSP older_frame_sp = thread.GetStackFrameAtIndex(i);
166 if (!older_frame_sp) {
167 // We can't unwind the next frame we should just get out of here &
168 // stop...
169 break;
170 }
171
172 const SymbolContext &older_context =
173 older_frame_sp->GetSymbolContext(eSymbolContextEverything);
174 if (IsEquivalentContext(older_context)) {
175 // If we have the next-branch-breakpoint in the range, we can just
176 // rely on that breakpoint to trigger once we return to the range.
178 return false;
179 new_plan_sp = thread.QueueThreadPlanForStepOutNoShouldStop(
180 false, nullptr, true, stop_others, eVoteNo, eVoteNoOpinion, 0,
181 m_status, true);
182 break;
183 } else {
184 new_plan_sp = thread.QueueThreadPlanForStepThrough(
185 m_stack_id, false, stop_others, m_status);
186 // If we found a way through, then we should stop recursing.
187 if (new_plan_sp)
188 break;
189 }
190 }
191 } else {
192 // If we're still in the range, keep going.
193 if (InRange()) {
195 return false;
196 }
197
198 if (!InSymbol()) {
199 // This one is a little tricky. Sometimes we may be in a stub or
200 // something similar, in which case we need to get out of there. But if
201 // we are in a stub then it's likely going to be hard to get out from
202 // here. It is probably easiest to step into the stub, and then it will
203 // be straight-forward to step out.
204 new_plan_sp = thread.QueueThreadPlanForStepThrough(m_stack_id, false,
205 stop_others, m_status);
206 } else {
207 // The current clang (at least through 424) doesn't always get the
208 // address range for the DW_TAG_inlined_subroutines right, so that when
209 // you leave the inlined range the line table says you are still in the
210 // source file of the inlining function. This is bad, because now you
211 // are missing the stack frame for the function containing the inlining,
212 // and if you sensibly do "finish" to get out of this function you will
213 // instead exit the containing function. To work around this, we check
214 // whether we are still in the source file we started in, and if not
215 // assume it is an error, and push a plan to get us out of this line and
216 // back to the containing file.
217
219 SymbolContext sc;
220 StackFrameSP frame_sp = thread.GetStackFrameAtIndex(0);
221 sc = frame_sp->GetSymbolContext(eSymbolContextEverything);
222 if (sc.line_entry.IsValid()) {
227 // Okay, find the next occurrence of this file in the line table:
229 if (line_table) {
230 Address cur_address = frame_sp->GetFrameCodeAddress();
231 uint32_t entry_idx;
232 LineEntry line_entry;
233 if (line_table->FindLineEntryByAddress(cur_address, line_entry,
234 &entry_idx)) {
235 LineEntry next_line_entry;
236 bool step_past_remaining_inline = false;
237 if (entry_idx > 0) {
238 // We require the previous line entry and the current line
239 // entry come from the same file. The other requirement is
240 // that the previous line table entry be part of an inlined
241 // block, we don't want to step past cases where people have
242 // inlined some code fragment by using #include <source-
243 // fragment.c> directly.
244 LineEntry prev_line_entry;
245 if (line_table->GetLineEntryAtIndex(entry_idx - 1,
246 prev_line_entry) &&
247 *prev_line_entry.original_file_sp ==
248 *line_entry.original_file_sp) {
249 SymbolContext prev_sc;
250 Address prev_address =
251 prev_line_entry.range.GetBaseAddress();
252 prev_address.CalculateSymbolContext(&prev_sc);
253 if (prev_sc.block) {
254 Block *inlined_block =
256 if (inlined_block) {
257 AddressRange inline_range;
258 inlined_block->GetRangeContainingAddress(prev_address,
259 inline_range);
260 if (!inline_range.ContainsFileAddress(cur_address)) {
261
262 step_past_remaining_inline = true;
263 }
264 }
265 }
266 }
267 }
268
269 if (step_past_remaining_inline) {
270 uint32_t look_ahead_step = 1;
271 while (line_table->GetLineEntryAtIndex(
272 entry_idx + look_ahead_step, next_line_entry)) {
273 // Make sure we haven't wandered out of the function we
274 // started from...
275 Address next_line_address =
276 next_line_entry.range.GetBaseAddress();
277 Function *next_line_function =
278 next_line_address.CalculateSymbolContextFunction();
279 if (next_line_function != m_addr_context.function)
280 break;
281
282 if (*next_line_entry.original_file_sp ==
284 const bool abort_other_plans = false;
285 const RunMode stop_other_threads = RunMode::eAllThreads;
286 lldb::addr_t cur_pc = thread.GetStackFrameAtIndex(0)
287 ->GetRegisterContext()
288 ->GetPC();
289 AddressRange step_range(
290 cur_pc,
291 next_line_address.GetLoadAddress(&GetTarget()) -
292 cur_pc);
293
294 new_plan_sp = thread.QueueThreadPlanForStepOverRange(
295 abort_other_plans, step_range, sc, stop_other_threads,
296 m_status);
297 break;
298 }
299 look_ahead_step++;
300 }
301 }
302 }
303 }
304 }
305 }
306 }
307 }
308 }
309
310 // If we get to this point, we're not going to use a previously set "next
311 // branch" breakpoint, so delete it:
313
314 // If we haven't figured out something to do yet, then ask the ShouldStopHere
315 // callback:
316 if (!new_plan_sp) {
317 new_plan_sp = CheckShouldStopHereAndQueueStepOut(frame_order, m_status);
318 }
319
320 if (!new_plan_sp)
321 m_no_more_plans = true;
322 else {
323 // Any new plan will be an implementation plan, so mark it private:
324 new_plan_sp->SetPrivate(true);
325 m_no_more_plans = false;
326 }
327
328 if (!new_plan_sp) {
329 // For efficiencies sake, we know we're done here so we don't have to do
330 // this calculation again in MischiefManaged.
332 return true;
333 } else
334 return false;
335}
336
338 // For crashes, breakpoint hits, signals, etc, let the base plan (or some
339 // plan above us) handle the stop. That way the user can see the stop, step
340 // around, and then when they are done, continue and have their step
341 // complete. The exception is if we've hit our "run to next branch"
342 // breakpoint. Note, unlike the step in range plan, we don't mark ourselves
343 // complete if we hit an unexplained breakpoint/crash.
344
345 Log *log = GetLog(LLDBLog::Step);
346 StopInfoSP stop_info_sp = GetPrivateStopInfo();
347 bool return_value;
348
349 if (stop_info_sp) {
350 StopReason reason = stop_info_sp->GetStopReason();
351
352 if (reason == eStopReasonTrace) {
353 return_value = true;
354 } else if (reason == eStopReasonBreakpoint) {
355 return_value = NextRangeBreakpointExplainsStop(stop_info_sp);
356 } else {
357 if (log)
358 log->PutCString("ThreadPlanStepInRange got asked if it explains the "
359 "stop for some reason other than step.");
360 return_value = false;
361 }
362 } else
363 return_value = true;
364
365 return return_value;
366}
367
369 bool current_plan) {
370 if (resume_state != eStateSuspended && m_first_resume) {
371 m_first_resume = false;
372 if (resume_state == eStateStepping && current_plan) {
373 Thread &thread = GetThread();
374 // See if we are about to step over an inlined call in the middle of the
375 // inlined stack, if so figure out its extents and reset our range to
376 // step over that.
377 bool in_inlined_stack = thread.DecrementCurrentInlinedDepth();
378 if (in_inlined_stack) {
379 Log *log = GetLog(LLDBLog::Step);
380 LLDB_LOGF(log,
381 "ThreadPlanStepInRange::DoWillResume: adjusting range to "
382 "the frame at inlined depth %d.",
383 thread.GetCurrentInlinedDepth());
384 StackFrameSP stack_sp = thread.GetStackFrameAtIndex(0);
385 if (stack_sp) {
386 Block *frame_block = stack_sp->GetFrameBlock();
387 lldb::addr_t curr_pc = thread.GetRegisterContext()->GetPC();
388 AddressRange my_range;
389 if (frame_block->GetRangeContainingLoadAddress(
390 curr_pc, m_process.GetTarget(), my_range)) {
391 m_address_ranges.clear();
392 m_address_ranges.push_back(my_range);
393 if (log) {
394 StreamString s;
395 const InlineFunctionInfo *inline_info =
396 frame_block->GetInlinedFunctionInfo();
397 const char *name;
398 if (inline_info)
399 name = inline_info->GetName().AsCString();
400 else
401 name = "<unknown-notinlined>";
402
403 s.Printf(
404 "Stepping over inlined function \"%s\" in inlined stack: ",
405 name);
406 DumpRanges(&s);
407 log->PutString(s.GetString());
408 }
409 }
410 }
411 }
412 }
413 }
414
415 return true;
416}
#define LLDB_LOGF(log,...)
Definition: Log.h:349
A section + offset based address range class.
Definition: AddressRange.h:25
Address & GetBaseAddress()
Get accessor for the base address of the range.
Definition: AddressRange.h:209
bool ContainsFileAddress(const Address &so_addr) const
Check if a section offset address is contained in this range.
A section + offset based address class.
Definition: Address.h:62
lldb::addr_t GetLoadAddress(Target *target) const
Get the load address.
Definition: Address.cpp:313
uint32_t CalculateSymbolContext(SymbolContext *sc, lldb::SymbolContextItem resolve_scope=lldb::eSymbolContextEverything) const
Reconstruct a symbol context from an address.
Definition: Address.cpp:831
Function * CalculateSymbolContextFunction() const
Definition: Address.cpp:871
A class that describes a single lexical block.
Definition: Block.h:41
Block * GetContainingInlinedBlock()
Get the inlined block that contains this block.
Definition: Block.cpp:208
const InlineFunctionInfo * GetInlinedFunctionInfo() const
Get const accessor for any inlined function information.
Definition: Block.h:276
bool GetRangeContainingAddress(const Address &addr, AddressRange &range)
Definition: Block.cpp:250
bool GetRangeContainingLoadAddress(lldb::addr_t load_addr, Target &target, AddressRange &range)
Definition: Block.cpp:278
LineTable * GetLineTable()
Get the line table for the compile unit.
const char * AsCString(const char *value_if_empty=nullptr) const
Get the string value as a C string.
Definition: ConstString.h:188
ValueType Clear(ValueType mask=~static_cast< ValueType >(0))
Clear one or more flags.
Definition: Flags.h:61
ValueType Set(ValueType mask)
Set one or more flags by logical OR'ing mask with the current flags.
Definition: Flags.h:73
A class that describes a function.
Definition: Function.h:399
A class that describes information for an inlined function.
Definition: Function.h:125
ConstString GetName() const
Definition: Function.cpp:96
A line table class.
Definition: LineTable.h:40
bool FindLineEntryByAddress(const Address &so_addr, LineEntry &line_entry, uint32_t *index_ptr=nullptr)
Find a line entry that contains the section offset address so_addr.
Definition: LineTable.cpp:188
bool GetLineEntryAtIndex(uint32_t idx, LineEntry &line_entry)
Get the line entry from the line table at index idx.
Definition: LineTable.cpp:179
void PutCString(const char *cstr)
Definition: Log.cpp:134
void PutString(llvm::StringRef str)
Definition: Log.cpp:136
Target & GetTarget()
Get the target object pointer for this module.
Definition: Process.h:1276
const char * AsCString(const char *default_error_str="unknown error") const
Get the error string associated with the current error.
Definition: Status.cpp:130
bool Success() const
Test for success condition.
Definition: Status.cpp:279
const char * GetData() const
Definition: StreamString.h:43
llvm::StringRef GetString() const
A stream class that can stream formatted output to a file.
Definition: Stream.h:28
llvm::raw_ostream & AsRawOstream()
Returns a raw_ostream that forwards the data to this Stream object.
Definition: Stream.h:401
size_t Printf(const char *format,...) __attribute__((format(printf
Output printf formatted output to the stream.
Definition: Stream.cpp:134
size_t PutChar(char ch)
Definition: Stream.cpp:131
Defines a symbol context baton that can be handed other debug core functions.
Definition: SymbolContext.h:34
Function * function
The Function for a given query.
Block * block
The Block for a given query.
CompileUnit * comp_unit
The CompileUnit for a given query.
Symbol * symbol
The Symbol for a given query.
LineEntry line_entry
The LineEntry for a given query.
lldb::ThreadPlanSP CheckShouldStopHereAndQueueStepOut(lldb::FrameComparison operation, Status &status)
bool DoPlanExplainsStop(Event *event_ptr) override
bool ShouldStop(Event *event_ptr) override
void GetDescription(Stream *s, lldb::DescriptionLevel level) override
Print a description of this thread to the stream s.
ThreadPlanStepOverRange(Thread &thread, const AddressRange &range, const SymbolContext &addr_context, lldb::RunMode stop_others, LazyBool step_out_avoids_no_debug)
void SetupAvoidNoDebug(LazyBool step_out_avoids_code_without_debug_info)
bool IsEquivalentContext(const SymbolContext &context)
bool DoWillResume(lldb::StateType resume_state, bool current_plan) override
bool NextRangeBreakpointExplainsStop(lldb::StopInfoSP stop_info_sp)
lldb::FrameComparison CompareCurrentFrameToStartFrame()
std::vector< AddressRange > m_address_ranges
void SetPlanComplete(bool success=true)
Definition: ThreadPlan.cpp:66
Thread & GetThread()
Returns the Thread that is using this thread plan.
Definition: ThreadPlan.cpp:42
lldb::StopInfoSP GetPrivateStopInfo()
Definition: ThreadPlan.h:517
bool GetStepOutAvoidsNoDebug() const
Definition: Thread.cpp:134
bool DecrementCurrentInlinedDepth()
Definition: Thread.h:412
virtual lldb::StackFrameSP GetStackFrameAtIndex(uint32_t idx)
Definition: Thread.h:405
virtual lldb::RegisterContextSP GetRegisterContext()=0
virtual lldb::ThreadPlanSP QueueThreadPlanForStepThrough(StackID &return_stack_id, bool abort_other_plans, bool stop_other_threads, Status &status)
Gets the plan used to step through the code that steps from a function call site at the current PC in...
Definition: Thread.cpp:1342
virtual lldb::ThreadPlanSP QueueThreadPlanForStepOutNoShouldStop(bool abort_other_plans, SymbolContext *addr_context, bool first_insn, bool stop_other_threads, Vote report_stop_vote, Vote report_run_vote, uint32_t frame_idx, Status &status, bool continue_to_next_branch=false)
Queue the plan used to step out of the function at the current PC of a thread.
Definition: Thread.cpp:1323
uint32_t GetCurrentInlinedDepth()
Definition: Thread.h:416
virtual lldb::ThreadPlanSP QueueThreadPlanForStepOverRange(bool abort_other_plans, const AddressRange &range, const SymbolContext &addr_context, lldb::RunMode stop_other_threads, Status &status, LazyBool step_out_avoids_code_without_debug_info=eLazyBoolCalculate)
Queues the plan used to step through an address range, stepping over function calls.
Definition: Thread.cpp:1253
A class that represents a running process on the host machine.
Definition: SBAttachInfo.h:14
Log * GetLog(Cat mask)
Retrieve the Log object for the channel associated with the given log enum.
Definition: Log.h:314
void DumpAddress(llvm::raw_ostream &s, uint64_t addr, uint32_t addr_size, const char *prefix=nullptr, const char *suffix=nullptr)
Output an address value to this stream.
Definition: Stream.cpp:108
Definition: SBAddress.h:15
std::shared_ptr< lldb_private::ThreadPlan > ThreadPlanSP
Definition: lldb-forward.h:441
std::shared_ptr< lldb_private::StackFrame > StackFrameSP
Definition: lldb-forward.h:412
DescriptionLevel
Description levels for "void GetDescription(Stream *, DescriptionLevel)" calls.
@ eDescriptionLevelBrief
@ eDescriptionLevelVerbose
FrameComparison
This is the return value for frame comparisons.
@ eFrameCompareOlder
@ eFrameCompareYounger
StateType
Process and Thread States.
@ eStateSuspended
Process or thread is in a suspended state as far as the debugger is concerned while other processes o...
@ eStateStepping
Process or thread is in the process of stepping and can not be examined.
std::shared_ptr< lldb_private::StopInfo > StopInfoSP
Definition: lldb-forward.h:419
uint64_t addr_t
Definition: lldb-types.h:79
StopReason
Thread stop reasons.
@ eStopReasonTrace
@ eStopReasonBreakpoint
RunMode
Thread Run Modes.
A line table entry class.
Definition: LineEntry.h:21
lldb::SupportFileSP original_file_sp
The original source file, from debug info.
Definition: LineEntry.h:138
bool IsValid() const
Check if a line entry object is valid.
Definition: LineEntry.cpp:33
AddressRange range
The section offset address range for this line entry.
Definition: LineEntry.h:134
bool DumpStopContext(Stream *s, bool show_fullpaths) const
Dumps information specific to a process that stops at this line entry to the supplied stream s.
Definition: LineEntry.cpp:37