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 }
267 
268 void
269 ThreadPlanCallFunction::ReportRegisterState (const char *message)
270 {
271     LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP | LIBLLDB_LOG_VERBOSE));
272     if (log)
273     {
274         StreamString strm;
275         RegisterContext *reg_ctx = m_thread.GetRegisterContext().get();
276 
277         log->PutCString(message);
278 
279         RegisterValue reg_value;
280 
281         for (uint32_t reg_idx = 0, num_registers = reg_ctx->GetRegisterCount();
282              reg_idx < num_registers;
283              ++reg_idx)
284         {
285             const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoAtIndex (reg_idx);
286             if (reg_ctx->ReadRegister(reg_info, reg_value))
287             {
288                 reg_value.Dump(&strm, reg_info, true, false, eFormatDefault);
289                 strm.EOL();
290             }
291         }
292         log->PutCString(strm.GetData());
293     }
294 }
295 
296 void
297 ThreadPlanCallFunction::DoTakedown ()
298 {
299     LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
300     if (!m_takedown_done)
301     {
302         ProcessSP process_sp (m_thread.GetProcess());
303         const ABI *abi = process_sp ? process_sp->GetABI().get() : NULL;
304         if (abi && m_return_type.IsValid())
305         {
306             const bool persistent = false;
307             m_return_valobj_sp = abi->GetReturnValueObject (m_thread, m_return_type, persistent);
308         }
309 
310         if (log)
311             log->Printf ("DoTakedown called for thread 0x%4.4llx, m_valid: %d complete: %d.\n", m_thread.GetID(), m_valid, IsPlanComplete());
312         m_takedown_done = true;
313         m_stop_address = m_thread.GetStackFrameAtIndex(0)->GetRegisterContext()->GetPC();
314         m_real_stop_info_sp = GetPrivateStopReason();
315         m_thread.RestoreThreadStateFromCheckpoint(m_stored_thread_state);
316         SetPlanComplete();
317         ClearBreakpoints();
318         if (log && log->GetVerbose())
319             ReportRegisterState ("Restoring thread state after function call.  Restored register state:");
320 
321     }
322     else
323     {
324         if (log)
325             log->Printf ("DoTakedown called as no-op for thread 0x%4.4llx, m_valid: %d complete: %d.\n", m_thread.GetID(), m_valid, IsPlanComplete());
326     }
327 }
328 
329 void
330 ThreadPlanCallFunction::WillPop ()
331 {
332     DoTakedown();
333 }
334 
335 void
336 ThreadPlanCallFunction::GetDescription (Stream *s, DescriptionLevel level)
337 {
338     if (level == eDescriptionLevelBrief)
339     {
340         s->Printf("Function call thread plan");
341     }
342     else
343     {
344         TargetSP target_sp (m_thread.CalculateTarget());
345         s->Printf("Thread plan to call 0x%llx", m_function_addr.GetLoadAddress(target_sp.get()));
346     }
347 }
348 
349 bool
350 ThreadPlanCallFunction::ValidatePlan (Stream *error)
351 {
352     if (!m_valid)
353         return false;
354 
355     return true;
356 }
357 
358 bool
359 ThreadPlanCallFunction::PlanExplainsStop ()
360 {
361     m_real_stop_info_sp = GetPrivateStopReason();
362 
363     // If our subplan knows why we stopped, even if it's done (which would forward the question to us)
364     // we answer yes.
365     if (m_subplan_sp.get() != NULL && m_subplan_sp->PlanExplainsStop())
366         return true;
367 
368     // Check if the breakpoint is one of ours.
369 
370     if (BreakpointsExplainStop())
371         return true;
372 
373     // If we don't want to discard this plan, than any stop we don't understand should be propagated up the stack.
374     if (!OkayToDiscard())
375         return false;
376 
377     // Otherwise, check the case where we stopped for an internal breakpoint, in that case, continue on.
378     // If it is not an internal breakpoint, consult OkayToDiscard.
379 
380     if (m_real_stop_info_sp && m_real_stop_info_sp->GetStopReason() == eStopReasonBreakpoint)
381     {
382         ProcessSP process_sp (m_thread.CalculateProcess());
383         uint64_t break_site_id = m_real_stop_info_sp->GetValue();
384         BreakpointSiteSP bp_site_sp;
385         if (process_sp)
386             bp_site_sp = process_sp->GetBreakpointSiteList().FindByID(break_site_id);
387         if (bp_site_sp)
388         {
389             uint32_t num_owners = bp_site_sp->GetNumberOfOwners();
390             bool is_internal = true;
391             for (uint32_t i = 0; i < num_owners; i++)
392             {
393                 Breakpoint &bp = bp_site_sp->GetOwnerAtIndex(i)->GetBreakpoint();
394 
395                 if (!bp.IsInternal())
396                 {
397                     is_internal = false;
398                     break;
399                 }
400             }
401             if (is_internal)
402                 return false;
403         }
404 
405         return OkayToDiscard();
406     }
407     else
408     {
409         // If the subplan is running, any crashes are attributable to us.
410         // If we want to discard the plan, then we say we explain the stop
411         // but if we are going to be discarded, let whoever is above us
412         // explain the stop.
413         return ((m_subplan_sp.get() != NULL) && !OkayToDiscard());
414     }
415 }
416 
417 bool
418 ThreadPlanCallFunction::ShouldStop (Event *event_ptr)
419 {
420     if (PlanExplainsStop())
421     {
422         ReportRegisterState ("Function completed.  Register state was:");
423 
424         DoTakedown();
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 #ifndef SINGLE_STEP_EXPRESSIONS
463     m_subplan_sp.reset(new ThreadPlanRunToAddress(m_thread, m_start_addr, m_stop_other_threads));
464 
465     m_thread.QueueThreadPlan(m_subplan_sp, false);
466     m_subplan_sp->SetPrivate (true);
467 #endif
468 }
469 
470 bool
471 ThreadPlanCallFunction::WillStop ()
472 {
473     return true;
474 }
475 
476 bool
477 ThreadPlanCallFunction::MischiefManaged ()
478 {
479     if (IsPlanComplete())
480     {
481         LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
482 
483         if (log)
484             log->Printf("Completed call function plan.");
485 
486         ThreadPlan::MischiefManaged ();
487         return true;
488     }
489     else
490     {
491         return false;
492     }
493 }
494 
495 void
496 ThreadPlanCallFunction::SetBreakpoints ()
497 {
498     ProcessSP process_sp (m_thread.CalculateProcess());
499     if (process_sp)
500     {
501         m_cxx_language_runtime = process_sp->GetLanguageRuntime(eLanguageTypeC_plus_plus);
502         m_objc_language_runtime = process_sp->GetLanguageRuntime(eLanguageTypeObjC);
503 
504         if (m_cxx_language_runtime)
505             m_cxx_language_runtime->SetExceptionBreakpoints();
506         if (m_objc_language_runtime)
507             m_objc_language_runtime->SetExceptionBreakpoints();
508     }
509 }
510 
511 void
512 ThreadPlanCallFunction::ClearBreakpoints ()
513 {
514     if (m_cxx_language_runtime)
515         m_cxx_language_runtime->ClearExceptionBreakpoints();
516     if (m_objc_language_runtime)
517         m_objc_language_runtime->ClearExceptionBreakpoints();
518 }
519 
520 bool
521 ThreadPlanCallFunction::BreakpointsExplainStop()
522 {
523     StopInfoSP stop_info_sp = GetPrivateStopReason();
524 
525     if (m_cxx_language_runtime &&
526         m_cxx_language_runtime->ExceptionBreakpointsExplainStop(stop_info_sp))
527         return true;
528 
529     if (m_objc_language_runtime &&
530         m_objc_language_runtime->ExceptionBreakpointsExplainStop(stop_info_sp))
531         return true;
532 
533     return false;
534 }
535