1 //===-- ThreadPlanCallFunction.cpp ------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "lldb/Target/ThreadPlanCallFunction.h"
11 
12 // C Includes
13 // C++ Includes
14 // Other libraries and framework includes
15 #include "llvm/Support/MachO.h"
16 // Project includes
17 #include "lldb/lldb-private-log.h"
18 #include "lldb/Breakpoint/Breakpoint.h"
19 #include "lldb/Breakpoint/BreakpointLocation.h"
20 #include "lldb/Core/Address.h"
21 #include "lldb/Core/Log.h"
22 #include "lldb/Core/Module.h"
23 #include "lldb/Core/Stream.h"
24 #include "lldb/Symbol/ObjectFile.h"
25 #include "lldb/Target/LanguageRuntime.h"
26 #include "lldb/Target/Process.h"
27 #include "lldb/Target/RegisterContext.h"
28 #include "lldb/Target/StopInfo.h"
29 #include "lldb/Target/Target.h"
30 #include "lldb/Target/Thread.h"
31 #include "lldb/Target/ThreadPlanRunToAddress.h"
32 
33 using namespace lldb;
34 using namespace lldb_private;
35 
36 //----------------------------------------------------------------------
37 // ThreadPlanCallFunction: Plan to call a single function
38 //----------------------------------------------------------------------
39 bool
40 ThreadPlanCallFunction::ConstructorSetup (Thread &thread,
41                                           ABI *& abi,
42                                           lldb::addr_t &start_load_addr,
43                                           lldb::addr_t &function_load_addr)
44 {
45     SetIsMasterPlan (true);
46     SetOkayToDiscard (false);
47     SetPrivate (true);
48 
49     ProcessSP process_sp (thread.GetProcess());
50     if (!process_sp)
51         return false;
52 
53     abi = process_sp->GetABI().get();
54 
55     if (!abi)
56         return false;
57 
58     TargetSP target_sp (thread.CalculateTarget());
59 
60     LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_STEP));
61 
62     SetBreakpoints();
63 
64     m_function_sp = thread.GetRegisterContext()->GetSP() - abi->GetRedZoneSize();
65     // If we can't read memory at the point of the process where we are planning to put our function, we're
66     // not going to get any further...
67     Error error;
68     process_sp->ReadUnsignedIntegerFromMemory(m_function_sp, 4, 0, error);
69     if (!error.Success())
70     {
71         if (log)
72             log->Printf ("ThreadPlanCallFunction(%p): Trying to put the stack in unreadable memory at: 0x%" PRIx64 ".", this, m_function_sp);
73         return false;
74     }
75 
76     Module *exe_module = target_sp->GetExecutableModulePointer();
77 
78     if (exe_module == NULL)
79     {
80         if (log)
81             log->Printf ("ThreadPlanCallFunction(%p): Can't execute code without an executable module.", this);
82         return false;
83     }
84     else
85     {
86         ObjectFile *objectFile = exe_module->GetObjectFile();
87         if (!objectFile)
88         {
89             if (log)
90                 log->Printf ("ThreadPlanCallFunction(%p): Could not find object file for module \"%s\".",
91                              this, exe_module->GetFileSpec().GetFilename().AsCString());
92             return false;
93         }
94         m_start_addr = objectFile->GetEntryPointAddress();
95         if (!m_start_addr.IsValid())
96         {
97             if (log)
98                 log->Printf ("ThreadPlanCallFunction(%p): Could not find entry point address for executable module \"%s\".",
99                              this, exe_module->GetFileSpec().GetFilename().AsCString());
100             return false;
101         }
102     }
103 
104     start_load_addr = m_start_addr.GetLoadAddress (target_sp.get());
105 
106     // Checkpoint the thread state so we can restore it later.
107     if (log && log->GetVerbose())
108         ReportRegisterState ("About to checkpoint thread before function call.  Original register state was:");
109 
110     if (!thread.CheckpointThreadState (m_stored_thread_state))
111     {
112         if (log)
113             log->Printf ("ThreadPlanCallFunction(%p): Setting up ThreadPlanCallFunction, failed to checkpoint thread state.", this);
114         return false;
115     }
116     function_load_addr = m_function_addr.GetLoadAddress (target_sp.get());
117 
118     return true;
119 }
120 
121 ThreadPlanCallFunction::ThreadPlanCallFunction (Thread &thread,
122                                                 Address &function,
123                                                 const ClangASTType &return_type,
124                                                 addr_t arg,
125                                                 bool stop_other_threads,
126                                                 bool unwind_on_error,
127                                                 bool ignore_breakpoints,
128                                                 addr_t *this_arg,
129                                                 addr_t *cmd_arg) :
130     ThreadPlan (ThreadPlan::eKindCallFunction, "Call function plan", thread, eVoteNoOpinion, eVoteNoOpinion),
131     m_valid (false),
132     m_stop_other_threads (stop_other_threads),
133     m_function_addr (function),
134     m_function_sp (0),
135     m_return_type (return_type),
136     m_takedown_done (false),
137     m_stop_address (LLDB_INVALID_ADDRESS),
138     m_unwind_on_error (unwind_on_error),
139     m_ignore_breakpoints (ignore_breakpoints)
140 {
141     lldb::addr_t start_load_addr;
142     ABI *abi;
143     lldb::addr_t function_load_addr;
144     if (!ConstructorSetup (thread, abi, start_load_addr, function_load_addr))
145         return;
146 
147     if (this_arg && cmd_arg)
148     {
149         if (!abi->PrepareTrivialCall (thread,
150                                       m_function_sp,
151                                       function_load_addr,
152                                       start_load_addr,
153                                       this_arg,
154                                       cmd_arg,
155                                       &arg))
156             return;
157     }
158     else if (this_arg)
159     {
160         if (!abi->PrepareTrivialCall (thread,
161                                       m_function_sp,
162                                       function_load_addr,
163                                       start_load_addr,
164                                       this_arg,
165                                       &arg))
166             return;
167     }
168     else
169     {
170         if (!abi->PrepareTrivialCall (thread,
171                                       m_function_sp,
172                                       function_load_addr,
173                                       start_load_addr,
174                                       &arg))
175             return;
176     }
177 
178     ReportRegisterState ("Function call was set up.  Register state was:");
179 
180     m_valid = true;
181 }
182 
183 
184 ThreadPlanCallFunction::ThreadPlanCallFunction (Thread &thread,
185                                                 Address &function,
186                                                 const ClangASTType &return_type,
187                                                 bool stop_other_threads,
188                                                 bool unwind_on_error,
189                                                 bool ignore_breakpoints,
190                                                 addr_t *arg1_ptr,
191                                                 addr_t *arg2_ptr,
192                                                 addr_t *arg3_ptr,
193                                                 addr_t *arg4_ptr,
194                                                 addr_t *arg5_ptr,
195                                                 addr_t *arg6_ptr) :
196     ThreadPlan (ThreadPlan::eKindCallFunction, "Call function plan", thread, eVoteNoOpinion, eVoteNoOpinion),
197     m_valid (false),
198     m_stop_other_threads (stop_other_threads),
199     m_function_addr (function),
200     m_function_sp (0),
201     m_return_type (return_type),
202     m_takedown_done (false),
203     m_stop_address (LLDB_INVALID_ADDRESS),
204     m_unwind_on_error (unwind_on_error),
205     m_ignore_breakpoints (ignore_breakpoints)
206 {
207     lldb::addr_t start_load_addr;
208     ABI *abi;
209     lldb::addr_t function_load_addr;
210     if (!ConstructorSetup (thread, abi, start_load_addr, function_load_addr))
211         return;
212 
213     if (!abi->PrepareTrivialCall (thread,
214                                   m_function_sp,
215                                   function_load_addr,
216                                   start_load_addr,
217                                   arg1_ptr,
218                                   arg2_ptr,
219                                   arg3_ptr,
220                                   arg4_ptr,
221                                   arg5_ptr,
222                                   arg6_ptr))
223     {
224             return;
225     }
226 
227     ReportRegisterState ("Function call was set up.  Register state was:");
228 
229     m_valid = true;
230 }
231 
232 ThreadPlanCallFunction::~ThreadPlanCallFunction ()
233 {
234     DoTakedown(true);
235 }
236 
237 void
238 ThreadPlanCallFunction::ReportRegisterState (const char *message)
239 {
240     LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP | LIBLLDB_LOG_VERBOSE));
241     if (log)
242     {
243         StreamString strm;
244         RegisterContext *reg_ctx = m_thread.GetRegisterContext().get();
245 
246         log->PutCString(message);
247 
248         RegisterValue reg_value;
249 
250         for (uint32_t reg_idx = 0, num_registers = reg_ctx->GetRegisterCount();
251              reg_idx < num_registers;
252              ++reg_idx)
253         {
254             const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoAtIndex (reg_idx);
255             if (reg_ctx->ReadRegister(reg_info, reg_value))
256             {
257                 reg_value.Dump(&strm, reg_info, true, false, eFormatDefault);
258                 strm.EOL();
259             }
260         }
261         log->PutCString(strm.GetData());
262     }
263 }
264 
265 void
266 ThreadPlanCallFunction::DoTakedown (bool success)
267 {
268     LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_STEP));
269 
270     if (!m_valid)
271     {
272         //Don't call DoTakedown if we were never valid to begin with.
273         if (log)
274             log->Printf ("ThreadPlanCallFunction(%p): Log called on ThreadPlanCallFunction that was never valid.", this);
275         return;
276     }
277 
278     if (!m_takedown_done)
279     {
280         if (success)
281         {
282             ProcessSP process_sp (m_thread.GetProcess());
283             const ABI *abi = process_sp ? process_sp->GetABI().get() : NULL;
284             if (abi && m_return_type.IsValid())
285             {
286                 const bool persistent = false;
287                 m_return_valobj_sp = abi->GetReturnValueObject (m_thread, m_return_type, persistent);
288             }
289         }
290         if (log)
291             log->Printf ("ThreadPlanCallFunction(%p): DoTakedown called for thread 0x%4.4" PRIx64 ", m_valid: %d complete: %d.\n", this, m_thread.GetID(), m_valid, IsPlanComplete());
292         m_takedown_done = true;
293         m_stop_address = m_thread.GetStackFrameAtIndex(0)->GetRegisterContext()->GetPC();
294         m_real_stop_info_sp = GetPrivateStopReason();
295         m_thread.RestoreRegisterStateFromCheckpoint(m_stored_thread_state);
296         SetPlanComplete(success);
297         ClearBreakpoints();
298         if (log && log->GetVerbose())
299             ReportRegisterState ("Restoring thread state after function call.  Restored register state:");
300 
301     }
302     else
303     {
304         if (log)
305             log->Printf ("ThreadPlanCallFunction(%p): DoTakedown called as no-op for thread 0x%4.4" PRIx64 ", m_valid: %d complete: %d.\n", this, m_thread.GetID(), m_valid, IsPlanComplete());
306     }
307 }
308 
309 void
310 ThreadPlanCallFunction::WillPop ()
311 {
312     DoTakedown(true);
313 }
314 
315 void
316 ThreadPlanCallFunction::GetDescription (Stream *s, DescriptionLevel level)
317 {
318     if (level == eDescriptionLevelBrief)
319     {
320         s->Printf("Function call thread plan");
321     }
322     else
323     {
324         TargetSP target_sp (m_thread.CalculateTarget());
325         s->Printf("Thread plan to call 0x%" PRIx64, m_function_addr.GetLoadAddress(target_sp.get()));
326     }
327 }
328 
329 bool
330 ThreadPlanCallFunction::ValidatePlan (Stream *error)
331 {
332     if (!m_valid)
333         return false;
334 
335     return true;
336 }
337 
338 bool
339 ThreadPlanCallFunction::PlanExplainsStop ()
340 {
341     m_real_stop_info_sp = GetPrivateStopReason();
342 
343     // If our subplan knows why we stopped, even if it's done (which would forward the question to us)
344     // we answer yes.
345     if (m_subplan_sp.get() != NULL && m_subplan_sp->PlanExplainsStop())
346     {
347         SetPlanComplete();
348         return true;
349     }
350 
351     // Check if the breakpoint is one of ours.
352 
353     StopReason stop_reason;
354     if (!m_real_stop_info_sp)
355         stop_reason = eStopReasonNone;
356     else
357         stop_reason = m_real_stop_info_sp->GetStopReason();
358 
359     if (stop_reason == eStopReasonBreakpoint && BreakpointsExplainStop())
360         return true;
361 
362     // If we don't want to discard this plan, than any stop we don't understand should be propagated up the stack.
363     if (!m_unwind_on_error)
364         return false;
365 
366     // Otherwise, check the case where we stopped for an internal breakpoint, in that case, continue on.
367     // If it is not an internal breakpoint, consult OkayToDiscard.
368 
369 
370     if (stop_reason == eStopReasonBreakpoint)
371     {
372         ProcessSP process_sp (m_thread.CalculateProcess());
373         uint64_t break_site_id = m_real_stop_info_sp->GetValue();
374         BreakpointSiteSP bp_site_sp;
375         if (process_sp)
376             bp_site_sp = process_sp->GetBreakpointSiteList().FindByID(break_site_id);
377         if (bp_site_sp)
378         {
379             uint32_t num_owners = bp_site_sp->GetNumberOfOwners();
380             bool is_internal = true;
381             for (uint32_t i = 0; i < num_owners; i++)
382             {
383                 Breakpoint &bp = bp_site_sp->GetOwnerAtIndex(i)->GetBreakpoint();
384 
385                 if (!bp.IsInternal())
386                 {
387                     is_internal = false;
388                     break;
389                 }
390             }
391             if (is_internal)
392                 return false;
393         }
394 
395         if (m_ignore_breakpoints)
396         {
397             DoTakedown(false);
398             return true;
399         }
400         else
401             return false;
402     }
403     else
404     {
405         // If the subplan is running, any crashes are attributable to us.
406         // If we want to discard the plan, then we say we explain the stop
407         // but if we are going to be discarded, let whoever is above us
408         // explain the stop.
409         SetPlanComplete(false);
410         if (m_subplan_sp)
411         {
412             if (m_unwind_on_error)
413             {
414                 DoTakedown(false);
415                 return true;
416             }
417             else
418                 return false;
419         }
420         else
421             return false;
422     }
423 }
424 
425 bool
426 ThreadPlanCallFunction::ShouldStop (Event *event_ptr)
427 {
428     // We do some computation in PlanExplainsStop that may or may not set the plan as complete.
429     // We need to do that here to make sure our state is correct.
430     PlanExplainsStop();
431 
432     if (IsPlanComplete())
433     {
434         ReportRegisterState ("Function completed.  Register state was:");
435 
436         DoTakedown(true);
437 
438         return true;
439     }
440     else
441     {
442         return false;
443     }
444 }
445 
446 bool
447 ThreadPlanCallFunction::StopOthers ()
448 {
449     return m_stop_other_threads;
450 }
451 
452 void
453 ThreadPlanCallFunction::SetStopOthers (bool new_value)
454 {
455     if (m_subplan_sp)
456     {
457         ThreadPlanRunToAddress *address_plan = static_cast<ThreadPlanRunToAddress *>(m_subplan_sp.get());
458         address_plan->SetStopOthers(new_value);
459     }
460     m_stop_other_threads = new_value;
461 }
462 
463 StateType
464 ThreadPlanCallFunction::GetPlanRunState ()
465 {
466     return eStateRunning;
467 }
468 
469 void
470 ThreadPlanCallFunction::DidPush ()
471 {
472 //#define SINGLE_STEP_EXPRESSIONS
473 
474     // Now set the thread state to "no reason" so we don't run with whatever signal was outstanding...
475     // Wait till the plan is pushed so we aren't changing the stop info till we're about to run.
476 
477     GetThread().SetStopInfoToNothing();
478 
479 #ifndef SINGLE_STEP_EXPRESSIONS
480     m_subplan_sp.reset(new ThreadPlanRunToAddress(m_thread, m_start_addr, m_stop_other_threads));
481 
482     m_thread.QueueThreadPlan(m_subplan_sp, false);
483     m_subplan_sp->SetPrivate (true);
484 #endif
485 }
486 
487 bool
488 ThreadPlanCallFunction::WillStop ()
489 {
490     return true;
491 }
492 
493 bool
494 ThreadPlanCallFunction::MischiefManaged ()
495 {
496     LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
497 
498     if (PlanExplainsStop() && !IsPlanComplete())
499     {
500         if (log)
501             log->Printf ("ThreadPlanCallFunction: Got into MischiefManaged, explained stop but was not complete.");
502     }
503 
504     if (IsPlanComplete())
505     {
506         if (log)
507             log->Printf("ThreadPlanCallFunction(%p): Completed call function plan.", this);
508 
509         ThreadPlan::MischiefManaged ();
510         return true;
511     }
512     else
513     {
514         return false;
515     }
516 }
517 
518 void
519 ThreadPlanCallFunction::SetBreakpoints ()
520 {
521     ProcessSP process_sp (m_thread.CalculateProcess());
522     if (process_sp)
523     {
524         m_cxx_language_runtime = process_sp->GetLanguageRuntime(eLanguageTypeC_plus_plus);
525         m_objc_language_runtime = process_sp->GetLanguageRuntime(eLanguageTypeObjC);
526 
527         if (m_cxx_language_runtime)
528             m_cxx_language_runtime->SetExceptionBreakpoints();
529         if (m_objc_language_runtime)
530             m_objc_language_runtime->SetExceptionBreakpoints();
531     }
532 }
533 
534 void
535 ThreadPlanCallFunction::ClearBreakpoints ()
536 {
537     if (m_cxx_language_runtime)
538         m_cxx_language_runtime->ClearExceptionBreakpoints();
539     if (m_objc_language_runtime)
540         m_objc_language_runtime->ClearExceptionBreakpoints();
541 }
542 
543 bool
544 ThreadPlanCallFunction::BreakpointsExplainStop()
545 {
546     StopInfoSP stop_info_sp = GetPrivateStopReason();
547 
548     if ((m_cxx_language_runtime &&
549             m_cxx_language_runtime->ExceptionBreakpointsExplainStop(stop_info_sp))
550        ||(m_objc_language_runtime &&
551             m_objc_language_runtime->ExceptionBreakpointsExplainStop(stop_info_sp)))
552     {
553         SetPlanComplete(false);
554         return true;
555     }
556 
557     // Finally, if the process is set to ignore breakpoints in function calls,
558     // then we explain all breakpoint stops.
559 
560     if (m_ignore_breakpoints)
561         return true;
562 
563     return false;
564 }
565 
566 bool
567 ThreadPlanCallFunction::RestoreThreadState()
568 {
569     return GetThread().RestoreThreadStateFromCheckpoint(m_stored_thread_state);
570 }
571 
572