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 discard_on_error,
127                                                 addr_t *this_arg,
128                                                 addr_t *cmd_arg) :
129     ThreadPlan (ThreadPlan::eKindCallFunction, "Call function plan", thread, eVoteNoOpinion, eVoteNoOpinion),
130     m_valid (false),
131     m_stop_other_threads (stop_other_threads),
132     m_function_addr (function),
133     m_function_sp (0),
134     m_return_type (return_type),
135     m_takedown_done (false),
136     m_stop_address (LLDB_INVALID_ADDRESS),
137     m_discard_on_error (discard_on_error)
138 {
139     lldb::addr_t start_load_addr;
140     ABI *abi;
141     lldb::addr_t function_load_addr;
142     if (!ConstructorSetup (thread, abi, start_load_addr, function_load_addr))
143         return;
144 
145     if (this_arg && cmd_arg)
146     {
147         if (!abi->PrepareTrivialCall (thread,
148                                       m_function_sp,
149                                       function_load_addr,
150                                       start_load_addr,
151                                       this_arg,
152                                       cmd_arg,
153                                       &arg))
154             return;
155     }
156     else if (this_arg)
157     {
158         if (!abi->PrepareTrivialCall (thread,
159                                       m_function_sp,
160                                       function_load_addr,
161                                       start_load_addr,
162                                       this_arg,
163                                       &arg))
164             return;
165     }
166     else
167     {
168         if (!abi->PrepareTrivialCall (thread,
169                                       m_function_sp,
170                                       function_load_addr,
171                                       start_load_addr,
172                                       &arg))
173             return;
174     }
175 
176     ReportRegisterState ("Function call was set up.  Register state was:");
177 
178     m_valid = true;
179 }
180 
181 
182 ThreadPlanCallFunction::ThreadPlanCallFunction (Thread &thread,
183                                                 Address &function,
184                                                 const ClangASTType &return_type,
185                                                 bool stop_other_threads,
186                                                 bool discard_on_error,
187                                                 addr_t *arg1_ptr,
188                                                 addr_t *arg2_ptr,
189                                                 addr_t *arg3_ptr,
190                                                 addr_t *arg4_ptr,
191                                                 addr_t *arg5_ptr,
192                                                 addr_t *arg6_ptr) :
193     ThreadPlan (ThreadPlan::eKindCallFunction, "Call function plan", thread, eVoteNoOpinion, eVoteNoOpinion),
194     m_valid (false),
195     m_stop_other_threads (stop_other_threads),
196     m_function_addr (function),
197     m_function_sp (0),
198     m_return_type (return_type),
199     m_takedown_done (false),
200     m_stop_address (LLDB_INVALID_ADDRESS),
201     m_discard_on_error (discard_on_error)
202 {
203     lldb::addr_t start_load_addr;
204     ABI *abi;
205     lldb::addr_t function_load_addr;
206     if (!ConstructorSetup (thread, abi, start_load_addr, function_load_addr))
207         return;
208 
209     if (!abi->PrepareTrivialCall (thread,
210                                   m_function_sp,
211                                   function_load_addr,
212                                   start_load_addr,
213                                   arg1_ptr,
214                                   arg2_ptr,
215                                   arg3_ptr,
216                                   arg4_ptr,
217                                   arg5_ptr,
218                                   arg6_ptr))
219     {
220             return;
221     }
222 
223     ReportRegisterState ("Function call was set up.  Register state was:");
224 
225     m_valid = true;
226 }
227 
228 ThreadPlanCallFunction::~ThreadPlanCallFunction ()
229 {
230     DoTakedown(true);
231 }
232 
233 void
234 ThreadPlanCallFunction::ReportRegisterState (const char *message)
235 {
236     LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP | LIBLLDB_LOG_VERBOSE));
237     if (log)
238     {
239         StreamString strm;
240         RegisterContext *reg_ctx = m_thread.GetRegisterContext().get();
241 
242         log->PutCString(message);
243 
244         RegisterValue reg_value;
245 
246         for (uint32_t reg_idx = 0, num_registers = reg_ctx->GetRegisterCount();
247              reg_idx < num_registers;
248              ++reg_idx)
249         {
250             const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoAtIndex (reg_idx);
251             if (reg_ctx->ReadRegister(reg_info, reg_value))
252             {
253                 reg_value.Dump(&strm, reg_info, true, false, eFormatDefault);
254                 strm.EOL();
255             }
256         }
257         log->PutCString(strm.GetData());
258     }
259 }
260 
261 void
262 ThreadPlanCallFunction::DoTakedown (bool success)
263 {
264     LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_STEP));
265 
266     if (!m_valid)
267     {
268         //Don't call DoTakedown if we were never valid to begin with.
269         if (log)
270             log->Printf ("ThreadPlanCallFunction(%p): Log called on ThreadPlanCallFunction that was never valid.", this);
271         return;
272     }
273 
274     if (!m_takedown_done)
275     {
276         if (success)
277         {
278             ProcessSP process_sp (m_thread.GetProcess());
279             const ABI *abi = process_sp ? process_sp->GetABI().get() : NULL;
280             if (abi && m_return_type.IsValid())
281             {
282                 const bool persistent = false;
283                 m_return_valobj_sp = abi->GetReturnValueObject (m_thread, m_return_type, persistent);
284             }
285         }
286         if (log)
287             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());
288         m_takedown_done = true;
289         m_stop_address = m_thread.GetStackFrameAtIndex(0)->GetRegisterContext()->GetPC();
290         m_real_stop_info_sp = GetPrivateStopReason();
291         m_thread.RestoreRegisterStateFromCheckpoint(m_stored_thread_state);
292         SetPlanComplete(success);
293         ClearBreakpoints();
294         if (log && log->GetVerbose())
295             ReportRegisterState ("Restoring thread state after function call.  Restored register state:");
296 
297     }
298     else
299     {
300         if (log)
301             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());
302     }
303 }
304 
305 void
306 ThreadPlanCallFunction::WillPop ()
307 {
308     DoTakedown(true);
309 }
310 
311 void
312 ThreadPlanCallFunction::GetDescription (Stream *s, DescriptionLevel level)
313 {
314     if (level == eDescriptionLevelBrief)
315     {
316         s->Printf("Function call thread plan");
317     }
318     else
319     {
320         TargetSP target_sp (m_thread.CalculateTarget());
321         s->Printf("Thread plan to call 0x%" PRIx64, m_function_addr.GetLoadAddress(target_sp.get()));
322     }
323 }
324 
325 bool
326 ThreadPlanCallFunction::ValidatePlan (Stream *error)
327 {
328     if (!m_valid)
329         return false;
330 
331     return true;
332 }
333 
334 bool
335 ThreadPlanCallFunction::PlanExplainsStop ()
336 {
337     m_real_stop_info_sp = GetPrivateStopReason();
338 
339     // If our subplan knows why we stopped, even if it's done (which would forward the question to us)
340     // we answer yes.
341     if (m_subplan_sp.get() != NULL && m_subplan_sp->PlanExplainsStop())
342         return true;
343 
344     // Check if the breakpoint is one of ours.
345 
346     StopReason stop_reason;
347     if (!m_real_stop_info_sp)
348         stop_reason = eStopReasonNone;
349     else
350         stop_reason = m_real_stop_info_sp->GetStopReason();
351 
352     if (stop_reason == eStopReasonBreakpoint && BreakpointsExplainStop())
353         return true;
354 
355     // If we don't want to discard this plan, than any stop we don't understand should be propagated up the stack.
356     if (!m_discard_on_error)
357         return false;
358 
359     // Otherwise, check the case where we stopped for an internal breakpoint, in that case, continue on.
360     // If it is not an internal breakpoint, consult OkayToDiscard.
361 
362 
363     if (stop_reason == eStopReasonBreakpoint)
364     {
365         ProcessSP process_sp (m_thread.CalculateProcess());
366         uint64_t break_site_id = m_real_stop_info_sp->GetValue();
367         BreakpointSiteSP bp_site_sp;
368         if (process_sp)
369             bp_site_sp = process_sp->GetBreakpointSiteList().FindByID(break_site_id);
370         if (bp_site_sp)
371         {
372             uint32_t num_owners = bp_site_sp->GetNumberOfOwners();
373             bool is_internal = true;
374             for (uint32_t i = 0; i < num_owners; i++)
375             {
376                 Breakpoint &bp = bp_site_sp->GetOwnerAtIndex(i)->GetBreakpoint();
377 
378                 if (!bp.IsInternal())
379                 {
380                     is_internal = false;
381                     break;
382                 }
383             }
384             if (is_internal)
385                 return false;
386         }
387 
388         if (m_discard_on_error)
389         {
390             DoTakedown(false);
391             return true;
392         }
393         else
394             return false;
395     }
396     else
397     {
398         // If the subplan is running, any crashes are attributable to us.
399         // If we want to discard the plan, then we say we explain the stop
400         // but if we are going to be discarded, let whoever is above us
401         // explain the stop.
402         if (m_subplan_sp)
403         {
404             if (m_discard_on_error)
405             {
406                 DoTakedown(false);
407                 return true;
408             }
409             else
410                 return false;
411         }
412         else
413             return false;
414     }
415 }
416 
417 bool
418 ThreadPlanCallFunction::ShouldStop (Event *event_ptr)
419 {
420     if (IsPlanComplete() || PlanExplainsStop())
421     {
422         ReportRegisterState ("Function completed.  Register state was:");
423 
424         DoTakedown(true);
425 
426         return true;
427     }
428     else
429     {
430         return false;
431     }
432 }
433 
434 bool
435 ThreadPlanCallFunction::StopOthers ()
436 {
437     return m_stop_other_threads;
438 }
439 
440 void
441 ThreadPlanCallFunction::SetStopOthers (bool new_value)
442 {
443     if (m_subplan_sp)
444     {
445         ThreadPlanRunToAddress *address_plan = static_cast<ThreadPlanRunToAddress *>(m_subplan_sp.get());
446         address_plan->SetStopOthers(new_value);
447     }
448     m_stop_other_threads = new_value;
449 }
450 
451 StateType
452 ThreadPlanCallFunction::GetPlanRunState ()
453 {
454     return eStateRunning;
455 }
456 
457 void
458 ThreadPlanCallFunction::DidPush ()
459 {
460 //#define SINGLE_STEP_EXPRESSIONS
461 
462     // Now set the thread state to "no reason" so we don't run with whatever signal was outstanding...
463     // Wait till the plan is pushed so we aren't changing the stop info till we're about to run.
464 
465     GetThread().SetStopInfoToNothing();
466 
467 #ifndef SINGLE_STEP_EXPRESSIONS
468     m_subplan_sp.reset(new ThreadPlanRunToAddress(m_thread, m_start_addr, m_stop_other_threads));
469 
470     m_thread.QueueThreadPlan(m_subplan_sp, false);
471     m_subplan_sp->SetPrivate (true);
472 #endif
473 }
474 
475 bool
476 ThreadPlanCallFunction::WillStop ()
477 {
478     return true;
479 }
480 
481 bool
482 ThreadPlanCallFunction::MischiefManaged ()
483 {
484     if (IsPlanComplete())
485     {
486         LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
487 
488         if (log)
489             log->Printf("ThreadPlanCallFunction(%p): Completed call function plan.", this);
490 
491         ThreadPlan::MischiefManaged ();
492         return true;
493     }
494     else
495     {
496         return false;
497     }
498 }
499 
500 void
501 ThreadPlanCallFunction::SetBreakpoints ()
502 {
503     ProcessSP process_sp (m_thread.CalculateProcess());
504     if (process_sp)
505     {
506         m_cxx_language_runtime = process_sp->GetLanguageRuntime(eLanguageTypeC_plus_plus);
507         m_objc_language_runtime = process_sp->GetLanguageRuntime(eLanguageTypeObjC);
508 
509         if (m_cxx_language_runtime)
510             m_cxx_language_runtime->SetExceptionBreakpoints();
511         if (m_objc_language_runtime)
512             m_objc_language_runtime->SetExceptionBreakpoints();
513     }
514 }
515 
516 void
517 ThreadPlanCallFunction::ClearBreakpoints ()
518 {
519     if (m_cxx_language_runtime)
520         m_cxx_language_runtime->ClearExceptionBreakpoints();
521     if (m_objc_language_runtime)
522         m_objc_language_runtime->ClearExceptionBreakpoints();
523 }
524 
525 bool
526 ThreadPlanCallFunction::BreakpointsExplainStop()
527 {
528     StopInfoSP stop_info_sp = GetPrivateStopReason();
529 
530     if (m_cxx_language_runtime &&
531         m_cxx_language_runtime->ExceptionBreakpointsExplainStop(stop_info_sp))
532         return true;
533 
534     if (m_objc_language_runtime &&
535         m_objc_language_runtime->ExceptionBreakpointsExplainStop(stop_info_sp))
536         return true;
537 
538     return false;
539 }
540 
541 bool
542 ThreadPlanCallFunction::RestoreThreadState()
543 {
544     return GetThread().RestoreThreadStateFromCheckpoint(m_stored_thread_state);
545 }
546 
547