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 bool
38 ThreadPlanCallFunction::ConstructorSetup (Thread &thread,
39                                           ABI *& abi,
40                                           lldb::addr_t &start_load_addr,
41                                           lldb::addr_t &function_load_addr)
42 {
43     SetIsMasterPlan (true);
44     SetOkayToDiscard (false);
45 
46     ProcessSP process_sp (thread.GetProcess());
47     if (!process_sp)
48         return false;
49 
50     abi = process_sp->GetABI().get();
51 
52     if (!abi)
53         return false;
54 
55     TargetSP target_sp (thread.CalculateTarget());
56 
57     LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_STEP));
58 
59     SetBreakpoints();
60 
61     m_function_sp = thread.GetRegisterContext()->GetSP() - abi->GetRedZoneSize();
62     // If we can't read memory at the point of the process where we are planning to put our function, we're
63     // not going to get any further...
64     Error error;
65     process_sp->ReadUnsignedIntegerFromMemory(m_function_sp, 4, 0, error);
66     if (!error.Success())
67     {
68         if (log)
69             log->Printf ("ThreadPlanCallFunction(%p): Trying to put the stack in unreadable memory at: 0x%llx.", this, m_function_sp);
70         return false;
71     }
72 
73     Module *exe_module = target_sp->GetExecutableModulePointer();
74 
75     if (exe_module == NULL)
76     {
77         if (log)
78             log->Printf ("ThreadPlanCallFunction(%p): Can't execute code without an executable module.", this);
79         return false;
80     }
81     else
82     {
83         ObjectFile *objectFile = exe_module->GetObjectFile();
84         if (!objectFile)
85         {
86             if (log)
87                 log->Printf ("ThreadPlanCallFunction(%p): Could not find object file for module \"%s\".",
88                              this, exe_module->GetFileSpec().GetFilename().AsCString());
89             return false;
90         }
91         m_start_addr = objectFile->GetEntryPointAddress();
92         if (!m_start_addr.IsValid())
93         {
94             if (log)
95                 log->Printf ("ThreadPlanCallFunction(%p): Could not find entry point address for executable module \"%s\".",
96                              this, exe_module->GetFileSpec().GetFilename().AsCString());
97             return false;
98         }
99     }
100 
101     start_load_addr = m_start_addr.GetLoadAddress (target_sp.get());
102 
103     // Checkpoint the thread state so we can restore it later.
104     if (log && log->GetVerbose())
105         ReportRegisterState ("About to checkpoint thread before function call.  Original register state was:");
106 
107     if (!thread.CheckpointThreadState (m_stored_thread_state))
108     {
109         if (log)
110             log->Printf ("ThreadPlanCallFunction(%p): Setting up ThreadPlanCallFunction, failed to checkpoint thread state.", this);
111         return false;
112     }
113     // Now set the thread state to "no reason" so we don't run with whatever signal was outstanding...
114     thread.SetStopInfoToNothing();
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 (NULL),
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(NULL),
198     m_return_type (return_type),
199     m_takedown_done (false),
200     m_stop_address (LLDB_INVALID_ADDRESS)
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%4.4llx, 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.RestoreThreadStateFromCheckpoint(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%4.4llx, 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%llx", 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 != NULL)
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 #ifndef SINGLE_STEP_EXPRESSIONS
462     m_subplan_sp.reset(new ThreadPlanRunToAddress(m_thread, m_start_addr, m_stop_other_threads));
463 
464     m_thread.QueueThreadPlan(m_subplan_sp, false);
465     m_subplan_sp->SetPrivate (true);
466 #endif
467 }
468 
469 bool
470 ThreadPlanCallFunction::WillStop ()
471 {
472     return true;
473 }
474 
475 bool
476 ThreadPlanCallFunction::MischiefManaged ()
477 {
478     if (IsPlanComplete())
479     {
480         LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
481 
482         if (log)
483             log->Printf("ThreadPlanCallFunction(%p): Completed call function plan.", this);
484 
485         ThreadPlan::MischiefManaged ();
486         return true;
487     }
488     else
489     {
490         return false;
491     }
492 }
493 
494 void
495 ThreadPlanCallFunction::SetBreakpoints ()
496 {
497     ProcessSP process_sp (m_thread.CalculateProcess());
498     if (process_sp)
499     {
500         m_cxx_language_runtime = process_sp->GetLanguageRuntime(eLanguageTypeC_plus_plus);
501         m_objc_language_runtime = process_sp->GetLanguageRuntime(eLanguageTypeObjC);
502 
503         if (m_cxx_language_runtime)
504             m_cxx_language_runtime->SetExceptionBreakpoints();
505         if (m_objc_language_runtime)
506             m_objc_language_runtime->SetExceptionBreakpoints();
507     }
508 }
509 
510 void
511 ThreadPlanCallFunction::ClearBreakpoints ()
512 {
513     if (m_cxx_language_runtime)
514         m_cxx_language_runtime->ClearExceptionBreakpoints();
515     if (m_objc_language_runtime)
516         m_objc_language_runtime->ClearExceptionBreakpoints();
517 }
518 
519 bool
520 ThreadPlanCallFunction::BreakpointsExplainStop()
521 {
522     StopInfoSP stop_info_sp = GetPrivateStopReason();
523 
524     if (m_cxx_language_runtime &&
525         m_cxx_language_runtime->ExceptionBreakpointsExplainStop(stop_info_sp))
526         return true;
527 
528     if (m_objc_language_runtime &&
529         m_objc_language_runtime->ExceptionBreakpointsExplainStop(stop_info_sp))
530         return true;
531 
532     return false;
533 }
534