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/Symbol/Symbol.h"
20#include "lldb/Target/DynamicLoader.h"
21#include "lldb/Target/ExecutionContext.h"
22#include "lldb/Target/Process.h"
23#include "lldb/Target/RegisterContext.h"
24#include "lldb/Target/Target.h"
25#include "lldb/Target/Thread.h"
26#include "lldb/Target/ThreadPlan.h"
27#include "lldb/Target/UnixSignals.h"
28
29using namespace lldb;
30using namespace lldb_private;
31
32const char *
33StopInfoMachException::GetDescription ()
34{
35    if (m_description.empty() && m_value != 0)
36    {
37        ExecutionContext exe_ctx (m_thread_wp.lock());
38        Target *target = exe_ctx.GetTargetPtr();
39        const llvm::Triple::ArchType cpu = target ? target->GetArchitecture().GetMachine() : llvm::Triple::UnknownArch;
40
41        const char *exc_desc = NULL;
42        const char *code_label = "code";
43        const char *code_desc = NULL;
44        const char *subcode_label = "subcode";
45        const char *subcode_desc = NULL;
46        switch (m_value)
47        {
48        case 1: // EXC_BAD_ACCESS
49            exc_desc = "EXC_BAD_ACCESS";
50            subcode_label = "address";
51            switch (cpu)
52            {
53            case llvm::Triple::x86:
54            case llvm::Triple::x86_64:
55                switch (m_exc_code)
56                {
57                case 0xd: code_desc = "EXC_I386_GPFLT"; m_exc_data_count = 1; break;
58                }
59                break;
60            case llvm::Triple::arm:
61                switch (m_exc_code)
62                {
63                case 0x101: code_desc = "EXC_ARM_DA_ALIGN"; break;
64                case 0x102: code_desc = "EXC_ARM_DA_DEBUG"; break;
65                }
66                break;
67
68            case llvm::Triple::ppc:
69            case llvm::Triple::ppc64:
70                switch (m_exc_code)
71                {
72                case 0x101: code_desc = "EXC_PPC_VM_PROT_READ"; break;
73                case 0x102: code_desc = "EXC_PPC_BADSPACE";     break;
74                case 0x103: code_desc = "EXC_PPC_UNALIGNED";    break;
75                }
76                break;
77
78            default:
79                break;
80            }
81            break;
82
83        case 2: // EXC_BAD_INSTRUCTION
84            exc_desc = "EXC_BAD_INSTRUCTION";
85            switch (cpu)
86            {
87            case llvm::Triple::x86:
88            case llvm::Triple::x86_64:
89                if (m_exc_code == 1)
90                    code_desc = "EXC_I386_INVOP";
91                break;
92
93            case llvm::Triple::ppc:
94            case llvm::Triple::ppc64:
95                switch (m_exc_code)
96                {
97                case 1: code_desc = "EXC_PPC_INVALID_SYSCALL"; break;
98                case 2: code_desc = "EXC_PPC_UNIPL_INST"; break;
99                case 3: code_desc = "EXC_PPC_PRIVINST"; break;
100                case 4: code_desc = "EXC_PPC_PRIVREG"; break;
101                case 5: code_desc = "EXC_PPC_TRACE"; break;
102                case 6: code_desc = "EXC_PPC_PERFMON"; break;
103                }
104                break;
105
106            case llvm::Triple::arm:
107                if (m_exc_code == 1)
108                    code_desc = "EXC_ARM_UNDEFINED";
109                break;
110
111            default:
112                break;
113            }
114            break;
115
116        case 3: // EXC_ARITHMETIC
117            exc_desc = "EXC_ARITHMETIC";
118            switch (cpu)
119            {
120            case llvm::Triple::x86:
121            case llvm::Triple::x86_64:
122                switch (m_exc_code)
123                {
124                case 1: code_desc = "EXC_I386_DIV"; break;
125                case 2: code_desc = "EXC_I386_INTO"; break;
126                case 3: code_desc = "EXC_I386_NOEXT"; break;
127                case 4: code_desc = "EXC_I386_EXTOVR"; break;
128                case 5: code_desc = "EXC_I386_EXTERR"; break;
129                case 6: code_desc = "EXC_I386_EMERR"; break;
130                case 7: code_desc = "EXC_I386_BOUND"; break;
131                case 8: code_desc = "EXC_I386_SSEEXTERR"; break;
132                }
133                break;
134
135            case llvm::Triple::ppc:
136            case llvm::Triple::ppc64:
137                switch (m_exc_code)
138                {
139                case 1: code_desc = "EXC_PPC_OVERFLOW"; break;
140                case 2: code_desc = "EXC_PPC_ZERO_DIVIDE"; break;
141                case 3: code_desc = "EXC_PPC_FLT_INEXACT"; break;
142                case 4: code_desc = "EXC_PPC_FLT_ZERO_DIVIDE"; break;
143                case 5: code_desc = "EXC_PPC_FLT_UNDERFLOW"; break;
144                case 6: code_desc = "EXC_PPC_FLT_OVERFLOW"; break;
145                case 7: code_desc = "EXC_PPC_FLT_NOT_A_NUMBER"; break;
146                }
147                break;
148
149            default:
150                break;
151            }
152            break;
153
154        case 4: // EXC_EMULATION
155            exc_desc = "EXC_EMULATION";
156            break;
157
158
159        case 5: // EXC_SOFTWARE
160            exc_desc = "EXC_SOFTWARE";
161            if (m_exc_code == 0x10003)
162            {
163                subcode_desc = "EXC_SOFT_SIGNAL";
164                subcode_label = "signo";
165            }
166            break;
167
168        case 6: // EXC_BREAKPOINT
169            {
170                exc_desc = "EXC_BREAKPOINT";
171                switch (cpu)
172                {
173                case llvm::Triple::x86:
174                case llvm::Triple::x86_64:
175                    switch (m_exc_code)
176                    {
177                    case 1: code_desc = "EXC_I386_SGL"; break;
178                    case 2: code_desc = "EXC_I386_BPT"; break;
179                    }
180                    break;
181
182                case llvm::Triple::ppc:
183                case llvm::Triple::ppc64:
184                    switch (m_exc_code)
185                    {
186                    case 1: code_desc = "EXC_PPC_BREAKPOINT"; break;
187                    }
188                    break;
189
190                case llvm::Triple::arm:
191                    switch (m_exc_code)
192                    {
193                    case 0x101: code_desc = "EXC_ARM_DA_ALIGN"; break;
194                    case 0x102: code_desc = "EXC_ARM_DA_DEBUG"; break;
195                    case 1: code_desc = "EXC_ARM_BREAKPOINT"; break;
196                    // FIXME temporary workaround, exc_code 0 does not really mean EXC_ARM_BREAKPOINT
197                    case 0: code_desc = "EXC_ARM_BREAKPOINT"; break;
198                    }
199                    break;
200
201                default:
202                    break;
203                }
204            }
205            break;
206
207        case 7:
208            exc_desc = "EXC_SYSCALL";
209            break;
210
211        case 8:
212            exc_desc = "EXC_MACH_SYSCALL";
213            break;
214
215        case 9:
216            exc_desc = "EXC_RPC_ALERT";
217            break;
218
219        case 10:
220            exc_desc = "EXC_CRASH";
221            break;
222        case 11:
223            exc_desc = "EXC_RESOURCE";
224            break;
225        case 12:
226            exc_desc = "EXC_GUARD";
227            break;
228        }
229
230        StreamString strm;
231
232        if (exc_desc)
233            strm.PutCString(exc_desc);
234        else
235            strm.Printf("EXC_??? (%" PRIu64 ")", m_value);
236
237        if (m_exc_data_count >= 1)
238        {
239            if (code_desc)
240                strm.Printf(" (%s=%s", code_label, code_desc);
241            else
242                strm.Printf(" (%s=%" PRIu64, code_label, m_exc_code);
243        }
244
245        if (m_exc_data_count >= 2)
246        {
247            if (subcode_desc)
248                strm.Printf(", %s=%s", subcode_label, subcode_desc);
249            else
250                strm.Printf(", %s=0x%" PRIx64, subcode_label, m_exc_subcode);
251        }
252
253        if (m_exc_data_count > 0)
254            strm.PutChar(')');
255
256        m_description.swap (strm.GetString());
257    }
258    return m_description.c_str();
259}
260
261
262
263
264
265StopInfoSP
266StopInfoMachException::CreateStopReasonWithMachException
267(
268    Thread &thread,
269    uint32_t exc_type,
270    uint32_t exc_data_count,
271    uint64_t exc_code,
272    uint64_t exc_sub_code,
273    uint64_t exc_sub_sub_code,
274    bool pc_already_adjusted,
275    bool adjust_pc_if_needed
276)
277{
278    if (exc_type != 0)
279    {
280        uint32_t pc_decrement = 0;
281        ExecutionContext exe_ctx (thread.shared_from_this());
282        Target *target = exe_ctx.GetTargetPtr();
283        const llvm::Triple::ArchType cpu = target ? target->GetArchitecture().GetMachine() : llvm::Triple::UnknownArch;
284
285        switch (exc_type)
286        {
287        case 1: // EXC_BAD_ACCESS
288            break;
289
290        case 2: // EXC_BAD_INSTRUCTION
291            switch (cpu)
292            {
293            case llvm::Triple::ppc:
294            case llvm::Triple::ppc64:
295                switch (exc_code)
296                {
297                case 1: // EXC_PPC_INVALID_SYSCALL
298                case 2: // EXC_PPC_UNIPL_INST
299                case 3: // EXC_PPC_PRIVINST
300                case 4: // EXC_PPC_PRIVREG
301                    break;
302                case 5: // EXC_PPC_TRACE
303                    return StopInfo::CreateStopReasonToTrace (thread);
304                case 6: // EXC_PPC_PERFMON
305                    break;
306                }
307                break;
308
309            default:
310                break;
311            }
312            break;
313
314        case 3: // EXC_ARITHMETIC
315        case 4: // EXC_EMULATION
316            break;
317
318        case 5: // EXC_SOFTWARE
319            if (exc_code == 0x10003) // EXC_SOFT_SIGNAL
320            {
321                if (exc_sub_code == 5)
322                {
323                    // On MacOSX, a SIGTRAP can signify that a process has called
324                    // exec, so we should check with our dynamic loader to verify.
325                    ProcessSP process_sp (thread.GetProcess());
326                    if (process_sp)
327                    {
328                        DynamicLoader *dynamic_loader = process_sp->GetDynamicLoader();
329                        if (dynamic_loader && dynamic_loader->ProcessDidExec())
330                        {
331                            // The program was re-exec'ed
332                            return StopInfo::CreateStopReasonWithExec (thread);
333                        }
334//                        if (!process_did_exec)
335//                        {
336//                            // We have a SIGTRAP, make sure we didn't exec by checking
337//                            // for the PC being at "_dyld_start"...
338//                            lldb::StackFrameSP frame_sp (thread.GetStackFrameAtIndex(0));
339//                            if (frame_sp)
340//                            {
341//                                const Symbol *symbol = frame_sp->GetSymbolContext(eSymbolContextSymbol).symbol;
342//                                if (symbol)
343//                                {
344//                                    if (symbol->GetName() == ConstString("_dyld_start"))
345//                                        process_did_exec = true;
346//                                }
347//                            }
348//                        }
349                    }
350                }
351                return StopInfo::CreateStopReasonWithSignal (thread, exc_sub_code);
352            }
353            break;
354
355        case 6: // EXC_BREAKPOINT
356            {
357                bool is_actual_breakpoint = false;
358                bool is_trace_if_actual_breakpoint_missing = false;
359                switch (cpu)
360                {
361                case llvm::Triple::x86:
362                case llvm::Triple::x86_64:
363                    if (exc_code == 1) // EXC_I386_SGL
364                    {
365                        if (!exc_sub_code)
366                            return StopInfo::CreateStopReasonToTrace(thread);
367
368                        // It's a watchpoint, then.
369                        // The exc_sub_code indicates the data break address.
370                        lldb::WatchpointSP wp_sp;
371                        if (target)
372                            wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
373                        if (wp_sp && wp_sp->IsEnabled())
374                        {
375                            // Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
376                            // Set the hardware index if that's the case.
377                            if (exc_data_count >=3)
378                                wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
379                            return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
380                        }
381                    }
382                    else if (exc_code == 2 ||   // EXC_I386_BPT
383                             exc_code == 3)     // EXC_I386_BPTFLT
384                    {
385                        // KDP returns EXC_I386_BPTFLT for trace breakpoints
386                        if (exc_code == 3)
387                            is_trace_if_actual_breakpoint_missing = true;
388
389                        is_actual_breakpoint = true;
390                        if (!pc_already_adjusted)
391                            pc_decrement = 1;
392                    }
393                    break;
394
395                case llvm::Triple::ppc:
396                case llvm::Triple::ppc64:
397                    is_actual_breakpoint = exc_code == 1; // EXC_PPC_BREAKPOINT
398                    break;
399
400                case llvm::Triple::arm:
401                    if (exc_code == 0x102) // EXC_ARM_DA_DEBUG
402                    {
403                        // It's a watchpoint, then, if the exc_sub_code indicates a known/enabled
404                        // data break address from our watchpoint list.
405                        lldb::WatchpointSP wp_sp;
406                        if (target)
407                            wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
408                        if (wp_sp && wp_sp->IsEnabled())
409                        {
410                            // Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
411                            // Set the hardware index if that's the case.
412                            if (exc_data_count >=3)
413                                wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
414                            return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
415                        }
416                        // EXC_ARM_DA_DEBUG seems to be reused for EXC_BREAKPOINT as well as EXC_BAD_ACCESS
417                        if (thread.GetTemporaryResumeState() == eStateStepping)
418                            return StopInfo::CreateStopReasonToTrace(thread);
419                    }
420                    else if (exc_code == 1) // EXC_ARM_BREAKPOINT
421                    {
422                        is_actual_breakpoint = true;
423                        is_trace_if_actual_breakpoint_missing = true;
424                    }
425                    else if (exc_code == 0) // FIXME not EXC_ARM_BREAKPOINT but a kernel is currently returning this so accept it as indicating a breakpoint until the kernel is fixed
426                    {
427                        is_actual_breakpoint = true;
428                        is_trace_if_actual_breakpoint_missing = true;
429                    }
430                    break;
431
432                default:
433                    break;
434                }
435
436                if (is_actual_breakpoint)
437                {
438                    RegisterContextSP reg_ctx_sp (thread.GetRegisterContext());
439                    addr_t pc = reg_ctx_sp->GetPC() - pc_decrement;
440
441                    ProcessSP process_sp (thread.CalculateProcess());
442
443                    lldb::BreakpointSiteSP bp_site_sp;
444                    if (process_sp)
445                        bp_site_sp = process_sp->GetBreakpointSiteList().FindByAddress(pc);
446                    if (bp_site_sp && bp_site_sp->IsEnabled())
447                    {
448                        // Update the PC if we were asked to do so, but only do
449                        // so if we find a breakpoint that we know about cause
450                        // this could be a trap instruction in the code
451                        if (pc_decrement > 0 && adjust_pc_if_needed)
452                            reg_ctx_sp->SetPC (pc);
453
454                        // If the breakpoint is for this thread, then we'll report the hit, but if it is for another thread,
455                        // we can just report no reason.  We don't need to worry about stepping over the breakpoint here, that
456                        // will be taken care of when the thread resumes and notices that there's a breakpoint under the pc.
457                        if (bp_site_sp->ValidForThisThread (&thread))
458                            return StopInfo::CreateStopReasonWithBreakpointSiteID (thread, bp_site_sp->GetID());
459                        else
460                            return StopInfoSP();
461                    }
462
463                    // Don't call this a trace if we weren't single stepping this thread.
464                    if (is_trace_if_actual_breakpoint_missing && thread.GetTemporaryResumeState() == eStateStepping)
465                    {
466                        return StopInfo::CreateStopReasonToTrace (thread);
467                    }
468                }
469            }
470            break;
471
472        case 7:     // EXC_SYSCALL
473        case 8:     // EXC_MACH_SYSCALL
474        case 9:     // EXC_RPC_ALERT
475        case 10:    // EXC_CRASH
476            break;
477        }
478
479        return StopInfoSP(new StopInfoMachException (thread, exc_type, exc_data_count, exc_code, exc_sub_code));
480    }
481    return StopInfoSP();
482}
483