1 //===-- StopInfoMachException.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 "StopInfoMachException.h"
11 
12 // C Includes
13 // C++ Includes
14 // Other libraries and framework includes
15 // Project includes
16 #include "lldb/Breakpoint/Watchpoint.h"
17 #include "lldb/Core/ArchSpec.h"
18 #include "lldb/Core/StreamString.h"
19 #include "lldb/Target/ExecutionContext.h"
20 #include "lldb/Target/Process.h"
21 #include "lldb/Target/RegisterContext.h"
22 #include "lldb/Target/Target.h"
23 #include "lldb/Target/Thread.h"
24 #include "lldb/Target/ThreadPlan.h"
25 #include "lldb/Target/UnixSignals.h"
26 
27 using namespace lldb;
28 using namespace lldb_private;
29 
30 const char *
31 StopInfoMachException::GetDescription ()
32 {
33     if (m_description.empty() && m_value != 0)
34     {
35         ExecutionContext exe_ctx (m_thread.shared_from_this());
36         Target *target = exe_ctx.GetTargetPtr();
37         const llvm::Triple::ArchType cpu = target ? target->GetArchitecture().GetMachine() : llvm::Triple::UnknownArch;
38 
39         const char *exc_desc = NULL;
40         const char *code_label = "code";
41         const char *code_desc = NULL;
42         const char *subcode_label = "subcode";
43         const char *subcode_desc = NULL;
44         switch (m_value)
45         {
46         case 1: // EXC_BAD_ACCESS
47             exc_desc = "EXC_BAD_ACCESS";
48             subcode_label = "address";
49             switch (cpu)
50             {
51             case llvm::Triple::arm:
52                 switch (m_exc_code)
53                 {
54                 case 0x101: code_desc = "EXC_ARM_DA_ALIGN"; break;
55                 case 0x102: code_desc = "EXC_ARM_DA_DEBUG"; break;
56                 }
57                 break;
58 
59             case llvm::Triple::ppc:
60             case llvm::Triple::ppc64:
61                 switch (m_exc_code)
62                 {
63                 case 0x101: code_desc = "EXC_PPC_VM_PROT_READ"; break;
64                 case 0x102: code_desc = "EXC_PPC_BADSPACE";     break;
65                 case 0x103: code_desc = "EXC_PPC_UNALIGNED";    break;
66                 }
67                 break;
68 
69             default:
70                 break;
71             }
72             break;
73 
74         case 2: // EXC_BAD_INSTRUCTION
75             exc_desc = "EXC_BAD_INSTRUCTION";
76             switch (cpu)
77             {
78             case llvm::Triple::x86:
79             case llvm::Triple::x86_64:
80                 if (m_exc_code == 1)
81                     code_desc = "EXC_I386_INVOP";
82                 break;
83 
84             case llvm::Triple::ppc:
85             case llvm::Triple::ppc64:
86                 switch (m_exc_code)
87                 {
88                 case 1: code_desc = "EXC_PPC_INVALID_SYSCALL"; break;
89                 case 2: code_desc = "EXC_PPC_UNIPL_INST"; break;
90                 case 3: code_desc = "EXC_PPC_PRIVINST"; break;
91                 case 4: code_desc = "EXC_PPC_PRIVREG"; break;
92                 case 5: code_desc = "EXC_PPC_TRACE"; break;
93                 case 6: code_desc = "EXC_PPC_PERFMON"; break;
94                 }
95                 break;
96 
97             case llvm::Triple::arm:
98                 if (m_exc_code == 1)
99                     code_desc = "EXC_ARM_UNDEFINED";
100                 break;
101 
102             default:
103                 break;
104             }
105             break;
106 
107         case 3: // EXC_ARITHMETIC
108             exc_desc = "EXC_ARITHMETIC";
109             switch (cpu)
110             {
111             case llvm::Triple::x86:
112             case llvm::Triple::x86_64:
113                 switch (m_exc_code)
114                 {
115                 case 1: code_desc = "EXC_I386_DIV"; break;
116                 case 2: code_desc = "EXC_I386_INTO"; break;
117                 case 3: code_desc = "EXC_I386_NOEXT"; break;
118                 case 4: code_desc = "EXC_I386_EXTOVR"; break;
119                 case 5: code_desc = "EXC_I386_EXTERR"; break;
120                 case 6: code_desc = "EXC_I386_EMERR"; break;
121                 case 7: code_desc = "EXC_I386_BOUND"; break;
122                 case 8: code_desc = "EXC_I386_SSEEXTERR"; break;
123                 }
124                 break;
125 
126             case llvm::Triple::ppc:
127             case llvm::Triple::ppc64:
128                 switch (m_exc_code)
129                 {
130                 case 1: code_desc = "EXC_PPC_OVERFLOW"; break;
131                 case 2: code_desc = "EXC_PPC_ZERO_DIVIDE"; break;
132                 case 3: code_desc = "EXC_PPC_FLT_INEXACT"; break;
133                 case 4: code_desc = "EXC_PPC_FLT_ZERO_DIVIDE"; break;
134                 case 5: code_desc = "EXC_PPC_FLT_UNDERFLOW"; break;
135                 case 6: code_desc = "EXC_PPC_FLT_OVERFLOW"; break;
136                 case 7: code_desc = "EXC_PPC_FLT_NOT_A_NUMBER"; break;
137                 }
138                 break;
139 
140             default:
141                 break;
142             }
143             break;
144 
145         case 4: // EXC_EMULATION
146             exc_desc = "EXC_EMULATION";
147             break;
148 
149 
150         case 5: // EXC_SOFTWARE
151             exc_desc = "EXC_SOFTWARE";
152             if (m_exc_code == 0x10003)
153             {
154                 subcode_desc = "EXC_SOFT_SIGNAL";
155                 subcode_label = "signo";
156             }
157             break;
158 
159         case 6: // EXC_BREAKPOINT
160             {
161                 exc_desc = "EXC_BREAKPOINT";
162                 switch (cpu)
163                 {
164                 case llvm::Triple::x86:
165                 case llvm::Triple::x86_64:
166                     switch (m_exc_code)
167                     {
168                     case 1: code_desc = "EXC_I386_SGL"; break;
169                     case 2: code_desc = "EXC_I386_BPT"; break;
170                     }
171                     break;
172 
173                 case llvm::Triple::ppc:
174                 case llvm::Triple::ppc64:
175                     switch (m_exc_code)
176                     {
177                     case 1: code_desc = "EXC_PPC_BREAKPOINT"; break;
178                     }
179                     break;
180 
181                 case llvm::Triple::arm:
182                     switch (m_exc_code)
183                     {
184                     case 0x101: code_desc = "EXC_ARM_DA_ALIGN"; break;
185                     case 0x102: code_desc = "EXC_ARM_DA_DEBUG"; break;
186                     case 1: code_desc = "EXC_ARM_BREAKPOINT"; break;
187                     }
188                     break;
189 
190                 default:
191                     break;
192                 }
193             }
194             break;
195 
196         case 7:
197             exc_desc = "EXC_SYSCALL";
198             break;
199 
200         case 8:
201             exc_desc = "EXC_MACH_SYSCALL";
202             break;
203 
204         case 9:
205             exc_desc = "EXC_RPC_ALERT";
206             break;
207 
208         case 10:
209             exc_desc = "EXC_CRASH";
210             break;
211         }
212 
213         StreamString strm;
214 
215         if (exc_desc)
216             strm.PutCString(exc_desc);
217         else
218             strm.Printf("EXC_??? (%llu)", m_value);
219 
220         if (m_exc_data_count >= 1)
221         {
222             if (code_desc)
223                 strm.Printf(" (%s=%s", code_label, code_desc);
224             else
225                 strm.Printf(" (%s=%llu", code_label, m_exc_code);
226         }
227 
228         if (m_exc_data_count >= 2)
229         {
230             if (subcode_desc)
231                 strm.Printf(", %s=%s", subcode_label, subcode_desc);
232             else
233                 strm.Printf(", %s=0x%llx", subcode_label, m_exc_subcode);
234         }
235 
236         if (m_exc_data_count > 0)
237             strm.PutChar(')');
238 
239         m_description.swap (strm.GetString());
240     }
241     return m_description.c_str();
242 }
243 
244 
245 
246 
247 
248 StopInfoSP
249 StopInfoMachException::CreateStopReasonWithMachException
250 (
251     Thread &thread,
252     uint32_t exc_type,
253     uint32_t exc_data_count,
254     uint64_t exc_code,
255     uint64_t exc_sub_code,
256     uint64_t exc_sub_sub_code,
257     bool pc_already_adjusted,
258     bool adjust_pc_if_needed
259 )
260 {
261     if (exc_type != 0)
262     {
263         uint32_t pc_decrement = 0;
264         ExecutionContext exe_ctx (thread.shared_from_this());
265         Target *target = exe_ctx.GetTargetPtr();
266         const llvm::Triple::ArchType cpu = target ? target->GetArchitecture().GetMachine() : llvm::Triple::UnknownArch;
267 
268         switch (exc_type)
269         {
270         case 1: // EXC_BAD_ACCESS
271             break;
272 
273         case 2: // EXC_BAD_INSTRUCTION
274             switch (cpu)
275             {
276             case llvm::Triple::ppc:
277             case llvm::Triple::ppc64:
278                 switch (exc_code)
279                 {
280                 case 1: // EXC_PPC_INVALID_SYSCALL
281                 case 2: // EXC_PPC_UNIPL_INST
282                 case 3: // EXC_PPC_PRIVINST
283                 case 4: // EXC_PPC_PRIVREG
284                     break;
285                 case 5: // EXC_PPC_TRACE
286                     return StopInfo::CreateStopReasonToTrace (thread);
287                 case 6: // EXC_PPC_PERFMON
288                     break;
289                 }
290                 break;
291 
292             default:
293                 break;
294             }
295             break;
296 
297         case 3: // EXC_ARITHMETIC
298         case 4: // EXC_EMULATION
299             break;
300 
301         case 5: // EXC_SOFTWARE
302             if (exc_code == 0x10003) // EXC_SOFT_SIGNAL
303                 return StopInfo::CreateStopReasonWithSignal (thread, exc_sub_code);
304             break;
305 
306         case 6: // EXC_BREAKPOINT
307             {
308                 bool is_software_breakpoint = false;
309                 bool is_trace_if_software_breakpoint_missing = false;
310                 switch (cpu)
311                 {
312                 case llvm::Triple::x86:
313                 case llvm::Triple::x86_64:
314                     if (exc_code == 1) // EXC_I386_SGL
315                     {
316                         if (!exc_sub_code)
317                             return StopInfo::CreateStopReasonToTrace(thread);
318 
319                         // It's a watchpoint, then.
320                         // The exc_sub_code indicates the data break address.
321                         lldb::WatchpointSP wp_sp;
322                         if (target)
323                             wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
324                         if (wp_sp && wp_sp->IsEnabled())
325                         {
326                             // Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
327                             // Set the hardware index if that's the case.
328                             if (exc_data_count >=3)
329                                 wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
330                             return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
331                         }
332                     }
333                     else if (exc_code == 2 ||   // EXC_I386_BPT
334                              exc_code == 3)     // EXC_I386_BPTFLT
335                     {
336                         // KDP returns EXC_I386_BPTFLT for trace breakpoints
337                         if (exc_code == 3)
338                             is_trace_if_software_breakpoint_missing = true;
339 
340                         is_software_breakpoint = true;
341                         if (!pc_already_adjusted)
342                             pc_decrement = 1;
343                     }
344                     break;
345 
346                 case llvm::Triple::ppc:
347                 case llvm::Triple::ppc64:
348                     is_software_breakpoint = exc_code == 1; // EXC_PPC_BREAKPOINT
349                     break;
350 
351                 case llvm::Triple::arm:
352                     if (exc_code == 0x102)
353                     {
354                         // It's a watchpoint, then, if the exc_sub_code indicates a known/enabled
355                         // data break address from our watchpoint list.
356                         lldb::WatchpointSP wp_sp;
357                         if (target)
358                             wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
359                         if (wp_sp && wp_sp->IsEnabled())
360                         {
361                             // Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
362                             // Set the hardware index if that's the case.
363                             if (exc_data_count >=3)
364                                 wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
365                             return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
366                         }
367                         // EXC_ARM_DA_DEBUG seems to be reused for EXC_BREAKPOINT as well as EXC_BAD_ACCESS
368                         return StopInfo::CreateStopReasonToTrace(thread);
369                     }
370                     else if (exc_code == 1)
371                     {
372                         is_software_breakpoint = true;
373                         is_trace_if_software_breakpoint_missing = true;
374                     }
375                     break;
376 
377                 default:
378                     break;
379                 }
380 
381                 if (is_software_breakpoint)
382                 {
383                     RegisterContextSP reg_ctx_sp (thread.GetRegisterContext());
384                     addr_t pc = reg_ctx_sp->GetPC() - pc_decrement;
385 
386                     ProcessSP process_sp (thread.CalculateProcess());
387 
388                     lldb::BreakpointSiteSP bp_site_sp;
389                     if (process_sp)
390                         bp_site_sp = process_sp->GetBreakpointSiteList().FindByAddress(pc);
391                     if (bp_site_sp && bp_site_sp->IsEnabled())
392                     {
393                         // Update the PC if we were asked to do so, but only do
394                         // so if we find a breakpoint that we know about cause
395                         // this could be a trap instruction in the code
396                         if (pc_decrement > 0 && adjust_pc_if_needed)
397                             reg_ctx_sp->SetPC (pc);
398 
399                         // If the breakpoint is for this thread, then we'll report the hit, but if it is for another thread,
400                         // we can just report no reason.  We don't need to worry about stepping over the breakpoint here, that
401                         // will be taken care of when the thread resumes and notices that there's a breakpoint under the pc.
402                         if (bp_site_sp->ValidForThisThread (&thread))
403                             return StopInfo::CreateStopReasonWithBreakpointSiteID (thread, bp_site_sp->GetID());
404                         else
405                             return StopInfoSP();
406                     }
407 
408                     if (is_trace_if_software_breakpoint_missing)
409                     {
410                         return StopInfo::CreateStopReasonToTrace (thread);
411                     }
412                 }
413             }
414             break;
415 
416         case 7:     // EXC_SYSCALL
417         case 8:     // EXC_MACH_SYSCALL
418         case 9:     // EXC_RPC_ALERT
419         case 10:    // EXC_CRASH
420             break;
421         }
422 
423         return StopInfoSP(new StopInfoMachException (thread, exc_type, exc_data_count, exc_code, exc_sub_code));
424     }
425     return StopInfoSP();
426 }
427