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