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