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