File: | src/gnu/usr.bin/clang/liblldbTarget/../../../llvm/lldb/source/Target/RegisterContextUnwind.cpp |
Warning: | line 1977, column 9 Value stored to 'cfa_reg_contents' is never read |
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1 | //===-- RegisterContextUnwind.cpp -----------------------------------------===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | |
9 | #include "lldb/Target/RegisterContextUnwind.h" |
10 | #include "lldb/Core/Address.h" |
11 | #include "lldb/Core/AddressRange.h" |
12 | #include "lldb/Core/Module.h" |
13 | #include "lldb/Core/Value.h" |
14 | #include "lldb/Expression/DWARFExpression.h" |
15 | #include "lldb/Symbol/ArmUnwindInfo.h" |
16 | #include "lldb/Symbol/CallFrameInfo.h" |
17 | #include "lldb/Symbol/DWARFCallFrameInfo.h" |
18 | #include "lldb/Symbol/FuncUnwinders.h" |
19 | #include "lldb/Symbol/Function.h" |
20 | #include "lldb/Symbol/ObjectFile.h" |
21 | #include "lldb/Symbol/Symbol.h" |
22 | #include "lldb/Symbol/SymbolContext.h" |
23 | #include "lldb/Symbol/SymbolFile.h" |
24 | #include "lldb/Target/ABI.h" |
25 | #include "lldb/Target/DynamicLoader.h" |
26 | #include "lldb/Target/ExecutionContext.h" |
27 | #include "lldb/Target/LanguageRuntime.h" |
28 | #include "lldb/Target/Platform.h" |
29 | #include "lldb/Target/Process.h" |
30 | #include "lldb/Target/SectionLoadList.h" |
31 | #include "lldb/Target/StackFrame.h" |
32 | #include "lldb/Target/Target.h" |
33 | #include "lldb/Target/Thread.h" |
34 | #include "lldb/Utility/DataBufferHeap.h" |
35 | #include "lldb/Utility/Log.h" |
36 | #include "lldb/Utility/RegisterValue.h" |
37 | #include "lldb/lldb-private.h" |
38 | |
39 | #include <memory> |
40 | |
41 | using namespace lldb; |
42 | using namespace lldb_private; |
43 | |
44 | static ConstString GetSymbolOrFunctionName(const SymbolContext &sym_ctx) { |
45 | if (sym_ctx.symbol) |
46 | return sym_ctx.symbol->GetName(); |
47 | else if (sym_ctx.function) |
48 | return sym_ctx.function->GetName(); |
49 | return ConstString(); |
50 | } |
51 | |
52 | RegisterContextUnwind::RegisterContextUnwind(Thread &thread, |
53 | const SharedPtr &next_frame, |
54 | SymbolContext &sym_ctx, |
55 | uint32_t frame_number, |
56 | UnwindLLDB &unwind_lldb) |
57 | : RegisterContext(thread, frame_number), m_thread(thread), |
58 | m_fast_unwind_plan_sp(), m_full_unwind_plan_sp(), |
59 | m_fallback_unwind_plan_sp(), m_all_registers_available(false), |
60 | m_frame_type(-1), m_cfa(LLDB_INVALID_ADDRESS0xffffffffffffffffULL), |
61 | m_afa(LLDB_INVALID_ADDRESS0xffffffffffffffffULL), m_start_pc(), m_current_pc(), |
62 | m_current_offset(0), m_current_offset_backed_up_one(0), |
63 | m_behaves_like_zeroth_frame(false), m_sym_ctx(sym_ctx), |
64 | m_sym_ctx_valid(false), m_frame_number(frame_number), m_registers(), |
65 | m_parent_unwind(unwind_lldb) { |
66 | m_sym_ctx.Clear(false); |
67 | m_sym_ctx_valid = false; |
68 | |
69 | if (IsFrameZero()) { |
70 | InitializeZerothFrame(); |
71 | } else { |
72 | InitializeNonZerothFrame(); |
73 | } |
74 | |
75 | // This same code exists over in the GetFullUnwindPlanForFrame() but it may |
76 | // not have been executed yet |
77 | if (IsFrameZero() || next_frame->m_frame_type == eTrapHandlerFrame || |
78 | next_frame->m_frame_type == eDebuggerFrame) { |
79 | m_all_registers_available = true; |
80 | } |
81 | } |
82 | |
83 | bool RegisterContextUnwind::IsUnwindPlanValidForCurrentPC( |
84 | lldb::UnwindPlanSP unwind_plan_sp, int &valid_pc_offset) { |
85 | if (!unwind_plan_sp) |
86 | return false; |
87 | |
88 | // check if m_current_pc is valid |
89 | if (unwind_plan_sp->PlanValidAtAddress(m_current_pc)) { |
90 | // yes - current offset can be used as is |
91 | valid_pc_offset = m_current_offset; |
92 | return true; |
93 | } |
94 | |
95 | // if m_current_offset <= 0, we've got nothing else to try |
96 | if (m_current_offset <= 0) |
97 | return false; |
98 | |
99 | // check pc - 1 to see if it's valid |
100 | Address pc_minus_one(m_current_pc); |
101 | pc_minus_one.SetOffset(m_current_pc.GetOffset() - 1); |
102 | if (unwind_plan_sp->PlanValidAtAddress(pc_minus_one)) { |
103 | // *valid_pc_offset = m_current_offset - 1; |
104 | valid_pc_offset = m_current_pc.GetOffset() - 1; |
105 | return true; |
106 | } |
107 | |
108 | return false; |
109 | } |
110 | |
111 | // Initialize a RegisterContextUnwind which is the first frame of a stack -- the |
112 | // zeroth frame or currently executing frame. |
113 | |
114 | void RegisterContextUnwind::InitializeZerothFrame() { |
115 | Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND(1u << 15))); |
116 | ExecutionContext exe_ctx(m_thread.shared_from_this()); |
117 | RegisterContextSP reg_ctx_sp = m_thread.GetRegisterContext(); |
118 | |
119 | if (reg_ctx_sp.get() == nullptr) { |
120 | m_frame_type = eNotAValidFrame; |
121 | UnwindLogMsg("frame does not have a register context"); |
122 | return; |
123 | } |
124 | |
125 | addr_t current_pc = reg_ctx_sp->GetPC(); |
126 | |
127 | if (current_pc == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
128 | m_frame_type = eNotAValidFrame; |
129 | UnwindLogMsg("frame does not have a pc"); |
130 | return; |
131 | } |
132 | |
133 | Process *process = exe_ctx.GetProcessPtr(); |
134 | |
135 | // Let ABIs fixup code addresses to make sure they are valid. In ARM ABIs |
136 | // this will strip bit zero in case we read a PC from memory or from the LR. |
137 | // (which would be a no-op in frame 0 where we get it from the register set, |
138 | // but still a good idea to make the call here for other ABIs that may |
139 | // exist.) |
140 | ABI *abi = process->GetABI().get(); |
141 | if (abi) |
142 | current_pc = abi->FixCodeAddress(current_pc); |
143 | |
144 | UnwindPlanSP lang_runtime_plan_sp = LanguageRuntime::GetRuntimeUnwindPlan( |
145 | m_thread, this, m_behaves_like_zeroth_frame); |
146 | if (lang_runtime_plan_sp.get()) { |
147 | UnwindLogMsg("This is an async frame"); |
148 | } |
149 | |
150 | // Initialize m_current_pc, an Address object, based on current_pc, an |
151 | // addr_t. |
152 | m_current_pc.SetLoadAddress(current_pc, &process->GetTarget()); |
153 | |
154 | // If we don't have a Module for some reason, we're not going to find |
155 | // symbol/function information - just stick in some reasonable defaults and |
156 | // hope we can unwind past this frame. |
157 | ModuleSP pc_module_sp(m_current_pc.GetModule()); |
158 | if (!m_current_pc.IsValid() || !pc_module_sp) { |
159 | UnwindLogMsg("using architectural default unwind method"); |
160 | } |
161 | |
162 | AddressRange addr_range; |
163 | m_sym_ctx_valid = m_current_pc.ResolveFunctionScope(m_sym_ctx, &addr_range); |
164 | |
165 | if (m_sym_ctx.symbol) { |
166 | UnwindLogMsg("with pc value of 0x%" PRIx64"llx" ", symbol name is '%s'", |
167 | current_pc, GetSymbolOrFunctionName(m_sym_ctx).AsCString("")); |
168 | } else if (m_sym_ctx.function) { |
169 | UnwindLogMsg("with pc value of 0x%" PRIx64"llx" ", function name is '%s'", |
170 | current_pc, GetSymbolOrFunctionName(m_sym_ctx).AsCString("")); |
171 | } else { |
172 | UnwindLogMsg("with pc value of 0x%" PRIx64"llx" |
173 | ", no symbol/function name is known.", |
174 | current_pc); |
175 | } |
176 | |
177 | if (IsTrapHandlerSymbol(process, m_sym_ctx)) { |
178 | m_frame_type = eTrapHandlerFrame; |
179 | } else { |
180 | // FIXME: Detect eDebuggerFrame here. |
181 | m_frame_type = eNormalFrame; |
182 | } |
183 | |
184 | // If we were able to find a symbol/function, set addr_range to the bounds of |
185 | // that symbol/function. else treat the current pc value as the start_pc and |
186 | // record no offset. |
187 | if (addr_range.GetBaseAddress().IsValid()) { |
188 | m_start_pc = addr_range.GetBaseAddress(); |
189 | if (m_current_pc.GetSection() == m_start_pc.GetSection()) { |
190 | m_current_offset = m_current_pc.GetOffset() - m_start_pc.GetOffset(); |
191 | } else if (m_current_pc.GetModule() == m_start_pc.GetModule()) { |
192 | // This means that whatever symbol we kicked up isn't really correct --- |
193 | // we should not cross section boundaries ... We really should NULL out |
194 | // the function/symbol in this case unless there is a bad assumption here |
195 | // due to inlined functions? |
196 | m_current_offset = |
197 | m_current_pc.GetFileAddress() - m_start_pc.GetFileAddress(); |
198 | } |
199 | m_current_offset_backed_up_one = m_current_offset; |
200 | } else { |
201 | m_start_pc = m_current_pc; |
202 | m_current_offset = -1; |
203 | m_current_offset_backed_up_one = -1; |
204 | } |
205 | |
206 | // We've set m_frame_type and m_sym_ctx before these calls. |
207 | |
208 | m_fast_unwind_plan_sp = GetFastUnwindPlanForFrame(); |
209 | m_full_unwind_plan_sp = GetFullUnwindPlanForFrame(); |
210 | |
211 | UnwindPlan::RowSP active_row; |
212 | lldb::RegisterKind row_register_kind = eRegisterKindGeneric; |
213 | |
214 | // If we have LanguageRuntime UnwindPlan for this unwind, use those |
215 | // rules to find the caller frame instead of the function's normal |
216 | // UnwindPlans. The full unwind plan for this frame will be |
217 | // the LanguageRuntime-provided unwind plan, and there will not be a |
218 | // fast unwind plan. |
219 | if (lang_runtime_plan_sp.get()) { |
220 | active_row = |
221 | lang_runtime_plan_sp->GetRowForFunctionOffset(m_current_offset); |
222 | row_register_kind = lang_runtime_plan_sp->GetRegisterKind(); |
223 | if (!ReadFrameAddress(row_register_kind, active_row->GetCFAValue(), |
224 | m_cfa)) { |
225 | UnwindLogMsg("Cannot set cfa"); |
226 | } else { |
227 | m_full_unwind_plan_sp = lang_runtime_plan_sp; |
228 | if (log) { |
229 | StreamString active_row_strm; |
230 | active_row->Dump(active_row_strm, lang_runtime_plan_sp.get(), &m_thread, |
231 | m_start_pc.GetLoadAddress(exe_ctx.GetTargetPtr())); |
232 | UnwindLogMsg("async active row: %s", active_row_strm.GetData()); |
233 | } |
234 | UnwindLogMsg("m_cfa = 0x%" PRIx64"llx" " m_afa = 0x%" PRIx64"llx", m_cfa, m_afa); |
235 | UnwindLogMsg( |
236 | "initialized async frame current pc is 0x%" PRIx64"llx" |
237 | " cfa is 0x%" PRIx64"llx" " afa is 0x%" PRIx64"llx", |
238 | (uint64_t)m_current_pc.GetLoadAddress(exe_ctx.GetTargetPtr()), |
239 | (uint64_t)m_cfa, (uint64_t)m_afa); |
240 | |
241 | return; |
242 | } |
243 | } |
244 | |
245 | if (m_full_unwind_plan_sp && |
246 | m_full_unwind_plan_sp->PlanValidAtAddress(m_current_pc)) { |
247 | active_row = |
248 | m_full_unwind_plan_sp->GetRowForFunctionOffset(m_current_offset); |
249 | row_register_kind = m_full_unwind_plan_sp->GetRegisterKind(); |
250 | if (active_row.get() && log) { |
251 | StreamString active_row_strm; |
252 | active_row->Dump(active_row_strm, m_full_unwind_plan_sp.get(), &m_thread, |
253 | m_start_pc.GetLoadAddress(exe_ctx.GetTargetPtr())); |
254 | UnwindLogMsg("%s", active_row_strm.GetData()); |
255 | } |
256 | } |
257 | |
258 | if (!active_row.get()) { |
259 | UnwindLogMsg("could not find an unwindplan row for this frame's pc"); |
260 | m_frame_type = eNotAValidFrame; |
261 | return; |
262 | } |
263 | |
264 | if (!ReadFrameAddress(row_register_kind, active_row->GetCFAValue(), m_cfa)) { |
265 | // Try the fall back unwind plan since the |
266 | // full unwind plan failed. |
267 | FuncUnwindersSP func_unwinders_sp; |
268 | UnwindPlanSP call_site_unwind_plan; |
269 | bool cfa_status = false; |
270 | |
271 | if (m_sym_ctx_valid) { |
272 | func_unwinders_sp = |
273 | pc_module_sp->GetUnwindTable().GetFuncUnwindersContainingAddress( |
274 | m_current_pc, m_sym_ctx); |
275 | } |
276 | |
277 | if (func_unwinders_sp.get() != nullptr) |
278 | call_site_unwind_plan = func_unwinders_sp->GetUnwindPlanAtCallSite( |
279 | process->GetTarget(), m_thread); |
280 | |
281 | if (call_site_unwind_plan.get() != nullptr) { |
282 | m_fallback_unwind_plan_sp = call_site_unwind_plan; |
283 | if (TryFallbackUnwindPlan()) |
284 | cfa_status = true; |
285 | } |
286 | if (!cfa_status) { |
287 | UnwindLogMsg("could not read CFA value for first frame."); |
288 | m_frame_type = eNotAValidFrame; |
289 | return; |
290 | } |
291 | } else |
292 | ReadFrameAddress(row_register_kind, active_row->GetAFAValue(), m_afa); |
293 | |
294 | UnwindLogMsg("initialized frame current pc is 0x%" PRIx64"llx" " cfa is 0x%" PRIx64"llx" |
295 | " afa is 0x%" PRIx64"llx" " using %s UnwindPlan", |
296 | (uint64_t)m_current_pc.GetLoadAddress(exe_ctx.GetTargetPtr()), |
297 | (uint64_t)m_cfa, |
298 | (uint64_t)m_afa, |
299 | m_full_unwind_plan_sp->GetSourceName().GetCString()); |
300 | } |
301 | |
302 | // Initialize a RegisterContextUnwind for the non-zeroth frame -- rely on the |
303 | // RegisterContextUnwind "below" it to provide things like its current pc value. |
304 | |
305 | void RegisterContextUnwind::InitializeNonZerothFrame() { |
306 | Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND(1u << 15))); |
307 | if (IsFrameZero()) { |
308 | m_frame_type = eNotAValidFrame; |
309 | UnwindLogMsg("non-zeroth frame tests positive for IsFrameZero -- that " |
310 | "shouldn't happen."); |
311 | return; |
312 | } |
313 | |
314 | if (!GetNextFrame().get() || !GetNextFrame()->IsValid()) { |
315 | m_frame_type = eNotAValidFrame; |
316 | UnwindLogMsg("Could not get next frame, marking this frame as invalid."); |
317 | return; |
318 | } |
319 | if (!m_thread.GetRegisterContext()) { |
320 | m_frame_type = eNotAValidFrame; |
321 | UnwindLogMsg("Could not get register context for this thread, marking this " |
322 | "frame as invalid."); |
323 | return; |
324 | } |
325 | |
326 | ExecutionContext exe_ctx(m_thread.shared_from_this()); |
327 | Process *process = exe_ctx.GetProcessPtr(); |
328 | |
329 | // Some languages may have a logical parent stack frame which is |
330 | // not a real stack frame, but the programmer would consider it to |
331 | // be the caller of the frame, e.g. Swift asynchronous frames. |
332 | // |
333 | // A LanguageRuntime may provide an UnwindPlan that is used in this |
334 | // stack trace base on the RegisterContext contents, intsead |
335 | // of the normal UnwindPlans we would use for the return-pc. |
336 | UnwindPlanSP lang_runtime_plan_sp = LanguageRuntime::GetRuntimeUnwindPlan( |
337 | m_thread, this, m_behaves_like_zeroth_frame); |
338 | if (lang_runtime_plan_sp.get()) { |
339 | UnwindLogMsg("This is an async frame"); |
340 | } |
341 | |
342 | addr_t pc; |
343 | if (!ReadGPRValue(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC0, pc)) { |
344 | UnwindLogMsg("could not get pc value"); |
345 | m_frame_type = eNotAValidFrame; |
346 | return; |
347 | } |
348 | |
349 | // Let ABIs fixup code addresses to make sure they are valid. In ARM ABIs |
350 | // this will strip bit zero in case we read a PC from memory or from the LR. |
351 | ABI *abi = process->GetABI().get(); |
352 | if (abi) |
353 | pc = abi->FixCodeAddress(pc); |
354 | |
355 | if (log) { |
356 | UnwindLogMsg("pc = 0x%" PRIx64"llx", pc); |
357 | addr_t reg_val; |
358 | if (ReadGPRValue(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_FP2, reg_val)) |
359 | UnwindLogMsg("fp = 0x%" PRIx64"llx", reg_val); |
360 | if (ReadGPRValue(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP1, reg_val)) |
361 | UnwindLogMsg("sp = 0x%" PRIx64"llx", reg_val); |
362 | } |
363 | |
364 | // A pc of 0x0 means it's the end of the stack crawl unless we're above a trap |
365 | // handler function |
366 | bool above_trap_handler = false; |
367 | if (GetNextFrame().get() && GetNextFrame()->IsValid() && |
368 | GetNextFrame()->IsTrapHandlerFrame()) |
369 | above_trap_handler = true; |
370 | |
371 | if (pc == 0 || pc == 0x1) { |
372 | if (!above_trap_handler) { |
373 | m_frame_type = eNotAValidFrame; |
374 | UnwindLogMsg("this frame has a pc of 0x0"); |
375 | return; |
376 | } |
377 | } |
378 | |
379 | const bool allow_section_end = true; |
380 | m_current_pc.SetLoadAddress(pc, &process->GetTarget(), allow_section_end); |
381 | |
382 | // If we don't have a Module for some reason, we're not going to find |
383 | // symbol/function information - just stick in some reasonable defaults and |
384 | // hope we can unwind past this frame. If we're above a trap handler, |
385 | // we may be at a bogus address because we jumped through a bogus function |
386 | // pointer and trapped, so don't force the arch default unwind plan in that |
387 | // case. |
388 | ModuleSP pc_module_sp(m_current_pc.GetModule()); |
389 | if ((!m_current_pc.IsValid() || !pc_module_sp) && |
390 | above_trap_handler == false) { |
391 | UnwindLogMsg("using architectural default unwind method"); |
392 | |
393 | // Test the pc value to see if we know it's in an unmapped/non-executable |
394 | // region of memory. |
395 | uint32_t permissions; |
396 | if (process->GetLoadAddressPermissions(pc, permissions) && |
397 | (permissions & ePermissionsExecutable) == 0) { |
398 | // If this is the second frame off the stack, we may have unwound the |
399 | // first frame incorrectly. But using the architecture default unwind |
400 | // plan may get us back on track -- albeit possibly skipping a real |
401 | // frame. Give this frame a clearly-invalid pc and see if we can get any |
402 | // further. |
403 | if (GetNextFrame().get() && GetNextFrame()->IsValid() && |
404 | GetNextFrame()->IsFrameZero()) { |
405 | UnwindLogMsg("had a pc of 0x%" PRIx64"llx" " which is not in executable " |
406 | "memory but on frame 1 -- " |
407 | "allowing it once.", |
408 | (uint64_t)pc); |
409 | m_frame_type = eSkipFrame; |
410 | } else { |
411 | // anywhere other than the second frame, a non-executable pc means |
412 | // we're off in the weeds -- stop now. |
413 | m_frame_type = eNotAValidFrame; |
414 | UnwindLogMsg("pc is in a non-executable section of memory and this " |
415 | "isn't the 2nd frame in the stack walk."); |
416 | return; |
417 | } |
418 | } |
419 | |
420 | if (abi) { |
421 | m_fast_unwind_plan_sp.reset(); |
422 | m_full_unwind_plan_sp = |
423 | std::make_shared<UnwindPlan>(lldb::eRegisterKindGeneric); |
424 | abi->CreateDefaultUnwindPlan(*m_full_unwind_plan_sp); |
425 | if (m_frame_type != eSkipFrame) // don't override eSkipFrame |
426 | { |
427 | m_frame_type = eNormalFrame; |
428 | } |
429 | m_all_registers_available = false; |
430 | m_current_offset = -1; |
431 | m_current_offset_backed_up_one = -1; |
432 | RegisterKind row_register_kind = m_full_unwind_plan_sp->GetRegisterKind(); |
433 | UnwindPlan::RowSP row = m_full_unwind_plan_sp->GetRowForFunctionOffset(0); |
434 | if (row.get()) { |
435 | if (!ReadFrameAddress(row_register_kind, row->GetCFAValue(), m_cfa)) { |
436 | UnwindLogMsg("failed to get cfa value"); |
437 | if (m_frame_type != eSkipFrame) // don't override eSkipFrame |
438 | { |
439 | m_frame_type = eNotAValidFrame; |
440 | } |
441 | return; |
442 | } |
443 | |
444 | ReadFrameAddress(row_register_kind, row->GetAFAValue(), m_afa); |
445 | |
446 | // A couple of sanity checks.. |
447 | if (m_cfa == LLDB_INVALID_ADDRESS0xffffffffffffffffULL || m_cfa == 0 || m_cfa == 1) { |
448 | UnwindLogMsg("could not find a valid cfa address"); |
449 | m_frame_type = eNotAValidFrame; |
450 | return; |
451 | } |
452 | |
453 | // m_cfa should point into the stack memory; if we can query memory |
454 | // region permissions, see if the memory is allocated & readable. |
455 | if (process->GetLoadAddressPermissions(m_cfa, permissions) && |
456 | (permissions & ePermissionsReadable) == 0) { |
457 | m_frame_type = eNotAValidFrame; |
458 | UnwindLogMsg( |
459 | "the CFA points to a region of memory that is not readable"); |
460 | return; |
461 | } |
462 | } else { |
463 | UnwindLogMsg("could not find a row for function offset zero"); |
464 | m_frame_type = eNotAValidFrame; |
465 | return; |
466 | } |
467 | |
468 | if (CheckIfLoopingStack()) { |
469 | TryFallbackUnwindPlan(); |
470 | if (CheckIfLoopingStack()) { |
471 | UnwindLogMsg("same CFA address as next frame, assuming the unwind is " |
472 | "looping - stopping"); |
473 | m_frame_type = eNotAValidFrame; |
474 | return; |
475 | } |
476 | } |
477 | |
478 | UnwindLogMsg("initialized frame cfa is 0x%" PRIx64"llx" " afa is 0x%" PRIx64"llx", |
479 | (uint64_t)m_cfa, (uint64_t)m_afa); |
480 | return; |
481 | } |
482 | m_frame_type = eNotAValidFrame; |
483 | UnwindLogMsg("could not find any symbol for this pc, or a default unwind " |
484 | "plan, to continue unwind."); |
485 | return; |
486 | } |
487 | |
488 | AddressRange addr_range; |
489 | m_sym_ctx_valid = m_current_pc.ResolveFunctionScope(m_sym_ctx, &addr_range); |
490 | |
491 | if (m_sym_ctx.symbol) { |
492 | UnwindLogMsg("with pc value of 0x%" PRIx64"llx" ", symbol name is '%s'", pc, |
493 | GetSymbolOrFunctionName(m_sym_ctx).AsCString("")); |
494 | } else if (m_sym_ctx.function) { |
495 | UnwindLogMsg("with pc value of 0x%" PRIx64"llx" ", function name is '%s'", pc, |
496 | GetSymbolOrFunctionName(m_sym_ctx).AsCString("")); |
497 | } else { |
498 | UnwindLogMsg("with pc value of 0x%" PRIx64"llx" |
499 | ", no symbol/function name is known.", |
500 | pc); |
501 | } |
502 | |
503 | bool decr_pc_and_recompute_addr_range; |
504 | |
505 | if (!m_sym_ctx_valid) { |
506 | // Always decrement and recompute if the symbol lookup failed |
507 | decr_pc_and_recompute_addr_range = true; |
508 | } else if (GetNextFrame()->m_frame_type == eTrapHandlerFrame || |
509 | GetNextFrame()->m_frame_type == eDebuggerFrame) { |
510 | // Don't decrement if we're "above" an asynchronous event like |
511 | // sigtramp. |
512 | decr_pc_and_recompute_addr_range = false; |
513 | } else if (!addr_range.GetBaseAddress().IsValid() || |
514 | addr_range.GetBaseAddress().GetSection() != m_current_pc.GetSection() || |
515 | addr_range.GetBaseAddress().GetOffset() != m_current_pc.GetOffset()) { |
516 | // If our "current" pc isn't the start of a function, no need |
517 | // to decrement and recompute. |
518 | decr_pc_and_recompute_addr_range = false; |
519 | } else if (IsTrapHandlerSymbol(process, m_sym_ctx)) { |
520 | // Signal dispatch may set the return address of the handler it calls to |
521 | // point to the first byte of a return trampoline (like __kernel_rt_sigreturn), |
522 | // so do not decrement and recompute if the symbol we already found is a trap |
523 | // handler. |
524 | decr_pc_and_recompute_addr_range = false; |
525 | } else if (m_behaves_like_zeroth_frame) { |
526 | decr_pc_and_recompute_addr_range = false; |
527 | } else { |
528 | // Decrement to find the function containing the call. |
529 | decr_pc_and_recompute_addr_range = true; |
530 | } |
531 | |
532 | // We need to back up the pc by 1 byte and re-search for the Symbol to handle |
533 | // the case where the "saved pc" value is pointing to the next function, e.g. |
534 | // if a function ends with a CALL instruction. |
535 | // FIXME this may need to be an architectural-dependent behavior; if so we'll |
536 | // need to add a member function |
537 | // to the ABI plugin and consult that. |
538 | if (decr_pc_and_recompute_addr_range) { |
539 | UnwindLogMsg("Backing up the pc value of 0x%" PRIx64"llx" |
540 | " by 1 and re-doing symbol lookup; old symbol was %s", |
541 | pc, GetSymbolOrFunctionName(m_sym_ctx).AsCString("")); |
542 | Address temporary_pc; |
543 | temporary_pc.SetLoadAddress(pc - 1, &process->GetTarget()); |
544 | m_sym_ctx.Clear(false); |
545 | m_sym_ctx_valid = temporary_pc.ResolveFunctionScope(m_sym_ctx, &addr_range); |
546 | |
547 | UnwindLogMsg("Symbol is now %s", |
548 | GetSymbolOrFunctionName(m_sym_ctx).AsCString("")); |
549 | } |
550 | |
551 | // If we were able to find a symbol/function, set addr_range_ptr to the |
552 | // bounds of that symbol/function. else treat the current pc value as the |
553 | // start_pc and record no offset. |
554 | if (addr_range.GetBaseAddress().IsValid()) { |
555 | m_start_pc = addr_range.GetBaseAddress(); |
556 | m_current_offset = pc - m_start_pc.GetLoadAddress(&process->GetTarget()); |
557 | m_current_offset_backed_up_one = m_current_offset; |
558 | if (decr_pc_and_recompute_addr_range && |
559 | m_current_offset_backed_up_one > 0) { |
560 | m_current_offset_backed_up_one--; |
561 | if (m_sym_ctx_valid) { |
562 | m_current_pc.SetLoadAddress(pc - 1, &process->GetTarget()); |
563 | } |
564 | } |
565 | } else { |
566 | m_start_pc = m_current_pc; |
567 | m_current_offset = -1; |
568 | m_current_offset_backed_up_one = -1; |
569 | } |
570 | |
571 | if (IsTrapHandlerSymbol(process, m_sym_ctx)) { |
572 | m_frame_type = eTrapHandlerFrame; |
573 | } else { |
574 | // FIXME: Detect eDebuggerFrame here. |
575 | if (m_frame_type != eSkipFrame) // don't override eSkipFrame |
576 | { |
577 | m_frame_type = eNormalFrame; |
578 | } |
579 | } |
580 | |
581 | UnwindPlan::RowSP active_row; |
582 | RegisterKind row_register_kind = eRegisterKindGeneric; |
583 | |
584 | // If we have LanguageRuntime UnwindPlan for this unwind, use those |
585 | // rules to find the caller frame instead of the function's normal |
586 | // UnwindPlans. The full unwind plan for this frame will be |
587 | // the LanguageRuntime-provided unwind plan, and there will not be a |
588 | // fast unwind plan. |
589 | if (lang_runtime_plan_sp.get()) { |
590 | active_row = |
591 | lang_runtime_plan_sp->GetRowForFunctionOffset(m_current_offset); |
592 | row_register_kind = lang_runtime_plan_sp->GetRegisterKind(); |
593 | if (!ReadFrameAddress(row_register_kind, active_row->GetCFAValue(), |
594 | m_cfa)) { |
595 | UnwindLogMsg("Cannot set cfa"); |
596 | } else { |
597 | m_full_unwind_plan_sp = lang_runtime_plan_sp; |
598 | if (log) { |
599 | StreamString active_row_strm; |
600 | active_row->Dump(active_row_strm, lang_runtime_plan_sp.get(), &m_thread, |
601 | m_start_pc.GetLoadAddress(exe_ctx.GetTargetPtr())); |
602 | UnwindLogMsg("async active row: %s", active_row_strm.GetData()); |
603 | } |
604 | UnwindLogMsg("m_cfa = 0x%" PRIx64"llx" " m_afa = 0x%" PRIx64"llx", m_cfa, m_afa); |
605 | UnwindLogMsg( |
606 | "initialized async frame current pc is 0x%" PRIx64"llx" |
607 | " cfa is 0x%" PRIx64"llx" " afa is 0x%" PRIx64"llx", |
608 | (uint64_t)m_current_pc.GetLoadAddress(exe_ctx.GetTargetPtr()), |
609 | (uint64_t)m_cfa, (uint64_t)m_afa); |
610 | |
611 | return; |
612 | } |
613 | } |
614 | |
615 | // We've set m_frame_type and m_sym_ctx before this call. |
616 | m_fast_unwind_plan_sp = GetFastUnwindPlanForFrame(); |
617 | |
618 | // Try to get by with just the fast UnwindPlan if possible - the full |
619 | // UnwindPlan may be expensive to get (e.g. if we have to parse the entire |
620 | // eh_frame section of an ObjectFile for the first time.) |
621 | |
622 | if (m_fast_unwind_plan_sp && |
623 | m_fast_unwind_plan_sp->PlanValidAtAddress(m_current_pc)) { |
624 | active_row = |
625 | m_fast_unwind_plan_sp->GetRowForFunctionOffset(m_current_offset); |
626 | row_register_kind = m_fast_unwind_plan_sp->GetRegisterKind(); |
627 | PropagateTrapHandlerFlagFromUnwindPlan(m_fast_unwind_plan_sp); |
628 | if (active_row.get() && log) { |
629 | StreamString active_row_strm; |
630 | active_row->Dump(active_row_strm, m_fast_unwind_plan_sp.get(), &m_thread, |
631 | m_start_pc.GetLoadAddress(exe_ctx.GetTargetPtr())); |
632 | UnwindLogMsg("Using fast unwind plan '%s'", |
633 | m_fast_unwind_plan_sp->GetSourceName().AsCString()); |
634 | UnwindLogMsg("active row: %s", active_row_strm.GetData()); |
635 | } |
636 | } else { |
637 | m_full_unwind_plan_sp = GetFullUnwindPlanForFrame(); |
638 | int valid_offset = -1; |
639 | if (IsUnwindPlanValidForCurrentPC(m_full_unwind_plan_sp, valid_offset)) { |
640 | active_row = m_full_unwind_plan_sp->GetRowForFunctionOffset(valid_offset); |
641 | row_register_kind = m_full_unwind_plan_sp->GetRegisterKind(); |
642 | PropagateTrapHandlerFlagFromUnwindPlan(m_full_unwind_plan_sp); |
643 | if (active_row.get() && log) { |
644 | StreamString active_row_strm; |
645 | active_row->Dump(active_row_strm, m_full_unwind_plan_sp.get(), |
646 | &m_thread, |
647 | m_start_pc.GetLoadAddress(exe_ctx.GetTargetPtr())); |
648 | UnwindLogMsg("Using full unwind plan '%s'", |
649 | m_full_unwind_plan_sp->GetSourceName().AsCString()); |
650 | UnwindLogMsg("active row: %s", active_row_strm.GetData()); |
651 | } |
652 | } |
653 | } |
654 | |
655 | if (!active_row.get()) { |
656 | m_frame_type = eNotAValidFrame; |
657 | UnwindLogMsg("could not find unwind row for this pc"); |
658 | return; |
659 | } |
660 | |
661 | if (!ReadFrameAddress(row_register_kind, active_row->GetCFAValue(), m_cfa)) { |
662 | UnwindLogMsg("failed to get cfa"); |
663 | m_frame_type = eNotAValidFrame; |
664 | return; |
665 | } |
666 | |
667 | ReadFrameAddress(row_register_kind, active_row->GetAFAValue(), m_afa); |
668 | |
669 | UnwindLogMsg("m_cfa = 0x%" PRIx64"llx" " m_afa = 0x%" PRIx64"llx", m_cfa, m_afa); |
670 | |
671 | if (CheckIfLoopingStack()) { |
672 | TryFallbackUnwindPlan(); |
673 | if (CheckIfLoopingStack()) { |
674 | UnwindLogMsg("same CFA address as next frame, assuming the unwind is " |
675 | "looping - stopping"); |
676 | m_frame_type = eNotAValidFrame; |
677 | return; |
678 | } |
679 | } |
680 | |
681 | UnwindLogMsg("initialized frame current pc is 0x%" PRIx64"llx" |
682 | " cfa is 0x%" PRIx64"llx" " afa is 0x%" PRIx64"llx", |
683 | (uint64_t)m_current_pc.GetLoadAddress(exe_ctx.GetTargetPtr()), |
684 | (uint64_t)m_cfa, |
685 | (uint64_t)m_afa); |
686 | } |
687 | |
688 | bool RegisterContextUnwind::CheckIfLoopingStack() { |
689 | // If we have a bad stack setup, we can get the same CFA value multiple times |
690 | // -- or even more devious, we can actually oscillate between two CFA values. |
691 | // Detect that here and break out to avoid a possible infinite loop in lldb |
692 | // trying to unwind the stack. To detect when we have the same CFA value |
693 | // multiple times, we compare the |
694 | // CFA of the current |
695 | // frame with the 2nd next frame because in some specail case (e.g. signal |
696 | // hanlders, hand written assembly without ABI compliance) we can have 2 |
697 | // frames with the same |
698 | // CFA (in theory we |
699 | // can have arbitrary number of frames with the same CFA, but more then 2 is |
700 | // very very unlikely) |
701 | |
702 | RegisterContextUnwind::SharedPtr next_frame = GetNextFrame(); |
703 | if (next_frame) { |
704 | RegisterContextUnwind::SharedPtr next_next_frame = |
705 | next_frame->GetNextFrame(); |
706 | addr_t next_next_frame_cfa = LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
707 | if (next_next_frame && next_next_frame->GetCFA(next_next_frame_cfa)) { |
708 | if (next_next_frame_cfa == m_cfa) { |
709 | // We have a loop in the stack unwind |
710 | return true; |
711 | } |
712 | } |
713 | } |
714 | return false; |
715 | } |
716 | |
717 | bool RegisterContextUnwind::IsFrameZero() const { return m_frame_number == 0; } |
718 | |
719 | bool RegisterContextUnwind::BehavesLikeZerothFrame() const { |
720 | if (m_frame_number == 0) |
721 | return true; |
722 | if (m_behaves_like_zeroth_frame) |
723 | return true; |
724 | return false; |
725 | } |
726 | |
727 | // Find a fast unwind plan for this frame, if possible. |
728 | // |
729 | // On entry to this method, |
730 | // |
731 | // 1. m_frame_type should already be set to eTrapHandlerFrame/eDebuggerFrame |
732 | // if either of those are correct, |
733 | // 2. m_sym_ctx should already be filled in, and |
734 | // 3. m_current_pc should have the current pc value for this frame |
735 | // 4. m_current_offset_backed_up_one should have the current byte offset into |
736 | // the function, maybe backed up by 1, -1 if unknown |
737 | |
738 | UnwindPlanSP RegisterContextUnwind::GetFastUnwindPlanForFrame() { |
739 | UnwindPlanSP unwind_plan_sp; |
740 | ModuleSP pc_module_sp(m_current_pc.GetModule()); |
741 | |
742 | if (!m_current_pc.IsValid() || !pc_module_sp || |
743 | pc_module_sp->GetObjectFile() == nullptr) |
744 | return unwind_plan_sp; |
745 | |
746 | if (IsFrameZero()) |
747 | return unwind_plan_sp; |
748 | |
749 | FuncUnwindersSP func_unwinders_sp( |
750 | pc_module_sp->GetUnwindTable().GetFuncUnwindersContainingAddress( |
751 | m_current_pc, m_sym_ctx)); |
752 | if (!func_unwinders_sp) |
753 | return unwind_plan_sp; |
754 | |
755 | // If we're in _sigtramp(), unwinding past this frame requires special |
756 | // knowledge. |
757 | if (m_frame_type == eTrapHandlerFrame || m_frame_type == eDebuggerFrame) |
758 | return unwind_plan_sp; |
759 | |
760 | unwind_plan_sp = func_unwinders_sp->GetUnwindPlanFastUnwind( |
761 | *m_thread.CalculateTarget(), m_thread); |
762 | if (unwind_plan_sp) { |
763 | if (unwind_plan_sp->PlanValidAtAddress(m_current_pc)) { |
764 | m_frame_type = eNormalFrame; |
765 | return unwind_plan_sp; |
766 | } else { |
767 | unwind_plan_sp.reset(); |
768 | } |
769 | } |
770 | return unwind_plan_sp; |
771 | } |
772 | |
773 | // On entry to this method, |
774 | // |
775 | // 1. m_frame_type should already be set to eTrapHandlerFrame/eDebuggerFrame |
776 | // if either of those are correct, |
777 | // 2. m_sym_ctx should already be filled in, and |
778 | // 3. m_current_pc should have the current pc value for this frame |
779 | // 4. m_current_offset_backed_up_one should have the current byte offset into |
780 | // the function, maybe backed up by 1, -1 if unknown |
781 | |
782 | UnwindPlanSP RegisterContextUnwind::GetFullUnwindPlanForFrame() { |
783 | UnwindPlanSP unwind_plan_sp; |
784 | UnwindPlanSP arch_default_unwind_plan_sp; |
785 | ExecutionContext exe_ctx(m_thread.shared_from_this()); |
786 | Process *process = exe_ctx.GetProcessPtr(); |
787 | ABI *abi = process ? process->GetABI().get() : nullptr; |
788 | if (abi) { |
789 | arch_default_unwind_plan_sp = |
790 | std::make_shared<UnwindPlan>(lldb::eRegisterKindGeneric); |
791 | abi->CreateDefaultUnwindPlan(*arch_default_unwind_plan_sp); |
792 | } else { |
793 | UnwindLogMsg( |
794 | "unable to get architectural default UnwindPlan from ABI plugin"); |
795 | } |
796 | |
797 | if (IsFrameZero() || GetNextFrame()->m_frame_type == eTrapHandlerFrame || |
798 | GetNextFrame()->m_frame_type == eDebuggerFrame) { |
799 | m_behaves_like_zeroth_frame = true; |
800 | // If this frame behaves like a 0th frame (currently executing or |
801 | // interrupted asynchronously), all registers can be retrieved. |
802 | m_all_registers_available = true; |
803 | } |
804 | |
805 | // If we've done a jmp 0x0 / bl 0x0 (called through a null function pointer) |
806 | // so the pc is 0x0 in the zeroth frame, we need to use the "unwind at first |
807 | // instruction" arch default UnwindPlan Also, if this Process can report on |
808 | // memory region attributes, any non-executable region means we jumped |
809 | // through a bad function pointer - handle the same way as 0x0. Note, if we |
810 | // have a symbol context & a symbol, we don't want to follow this code path. |
811 | // This is for jumping to memory regions without any information available. |
812 | |
813 | if ((!m_sym_ctx_valid || |
814 | (m_sym_ctx.function == nullptr && m_sym_ctx.symbol == nullptr)) && |
815 | m_behaves_like_zeroth_frame && m_current_pc.IsValid()) { |
816 | uint32_t permissions; |
817 | addr_t current_pc_addr = |
818 | m_current_pc.GetLoadAddress(exe_ctx.GetTargetPtr()); |
819 | if (current_pc_addr == 0 || |
820 | (process && |
821 | process->GetLoadAddressPermissions(current_pc_addr, permissions) && |
822 | (permissions & ePermissionsExecutable) == 0)) { |
823 | if (abi) { |
824 | unwind_plan_sp = |
825 | std::make_shared<UnwindPlan>(lldb::eRegisterKindGeneric); |
826 | abi->CreateFunctionEntryUnwindPlan(*unwind_plan_sp); |
827 | m_frame_type = eNormalFrame; |
828 | return unwind_plan_sp; |
829 | } |
830 | } |
831 | } |
832 | |
833 | // No Module for the current pc, try using the architecture default unwind. |
834 | ModuleSP pc_module_sp(m_current_pc.GetModule()); |
835 | if (!m_current_pc.IsValid() || !pc_module_sp || |
836 | pc_module_sp->GetObjectFile() == nullptr) { |
837 | m_frame_type = eNormalFrame; |
838 | return arch_default_unwind_plan_sp; |
839 | } |
840 | |
841 | FuncUnwindersSP func_unwinders_sp; |
842 | if (m_sym_ctx_valid) { |
843 | func_unwinders_sp = |
844 | pc_module_sp->GetUnwindTable().GetFuncUnwindersContainingAddress( |
845 | m_current_pc, m_sym_ctx); |
846 | } |
847 | |
848 | // No FuncUnwinders available for this pc (stripped function symbols, lldb |
849 | // could not augment its function table with another source, like |
850 | // LC_FUNCTION_STARTS or eh_frame in ObjectFileMachO). See if eh_frame or the |
851 | // .ARM.exidx tables have unwind information for this address, else fall back |
852 | // to the architectural default unwind. |
853 | if (!func_unwinders_sp) { |
854 | m_frame_type = eNormalFrame; |
855 | |
856 | if (!pc_module_sp || !pc_module_sp->GetObjectFile() || |
857 | !m_current_pc.IsValid()) |
858 | return arch_default_unwind_plan_sp; |
859 | |
860 | // Even with -fomit-frame-pointer, we can try eh_frame to get back on |
861 | // track. |
862 | DWARFCallFrameInfo *eh_frame = |
863 | pc_module_sp->GetUnwindTable().GetEHFrameInfo(); |
864 | if (eh_frame) { |
865 | unwind_plan_sp = std::make_shared<UnwindPlan>(lldb::eRegisterKindGeneric); |
866 | if (eh_frame->GetUnwindPlan(m_current_pc, *unwind_plan_sp)) |
867 | return unwind_plan_sp; |
868 | else |
869 | unwind_plan_sp.reset(); |
870 | } |
871 | |
872 | ArmUnwindInfo *arm_exidx = |
873 | pc_module_sp->GetUnwindTable().GetArmUnwindInfo(); |
874 | if (arm_exidx) { |
875 | unwind_plan_sp = std::make_shared<UnwindPlan>(lldb::eRegisterKindGeneric); |
876 | if (arm_exidx->GetUnwindPlan(exe_ctx.GetTargetRef(), m_current_pc, |
877 | *unwind_plan_sp)) |
878 | return unwind_plan_sp; |
879 | else |
880 | unwind_plan_sp.reset(); |
881 | } |
882 | |
883 | CallFrameInfo *object_file_unwind = |
884 | pc_module_sp->GetUnwindTable().GetObjectFileUnwindInfo(); |
885 | if (object_file_unwind) { |
886 | unwind_plan_sp = std::make_shared<UnwindPlan>(lldb::eRegisterKindGeneric); |
887 | if (object_file_unwind->GetUnwindPlan(m_current_pc, *unwind_plan_sp)) |
888 | return unwind_plan_sp; |
889 | else |
890 | unwind_plan_sp.reset(); |
891 | } |
892 | |
893 | return arch_default_unwind_plan_sp; |
894 | } |
895 | |
896 | // If we're in _sigtramp(), unwinding past this frame requires special |
897 | // knowledge. On Mac OS X this knowledge is properly encoded in the eh_frame |
898 | // section, so prefer that if available. On other platforms we may need to |
899 | // provide a platform-specific UnwindPlan which encodes the details of how to |
900 | // unwind out of sigtramp. |
901 | if (m_frame_type == eTrapHandlerFrame && process) { |
902 | m_fast_unwind_plan_sp.reset(); |
903 | unwind_plan_sp = |
904 | func_unwinders_sp->GetEHFrameUnwindPlan(process->GetTarget()); |
905 | if (!unwind_plan_sp) |
906 | unwind_plan_sp = |
907 | func_unwinders_sp->GetObjectFileUnwindPlan(process->GetTarget()); |
908 | if (unwind_plan_sp && unwind_plan_sp->PlanValidAtAddress(m_current_pc) && |
909 | unwind_plan_sp->GetSourcedFromCompiler() == eLazyBoolYes) { |
910 | return unwind_plan_sp; |
911 | } |
912 | } |
913 | |
914 | // Ask the DynamicLoader if the eh_frame CFI should be trusted in this frame |
915 | // even when it's frame zero This comes up if we have hand-written functions |
916 | // in a Module and hand-written eh_frame. The assembly instruction |
917 | // inspection may fail and the eh_frame CFI were probably written with some |
918 | // care to do the right thing. It'd be nice if there was a way to ask the |
919 | // eh_frame directly if it is asynchronous (can be trusted at every |
920 | // instruction point) or synchronous (the normal case - only at call sites). |
921 | // But there is not. |
922 | if (process && process->GetDynamicLoader() && |
923 | process->GetDynamicLoader()->AlwaysRelyOnEHUnwindInfo(m_sym_ctx)) { |
924 | // We must specifically call the GetEHFrameUnwindPlan() method here -- |
925 | // normally we would call GetUnwindPlanAtCallSite() -- because CallSite may |
926 | // return an unwind plan sourced from either eh_frame (that's what we |
927 | // intend) or compact unwind (this won't work) |
928 | unwind_plan_sp = |
929 | func_unwinders_sp->GetEHFrameUnwindPlan(process->GetTarget()); |
930 | if (!unwind_plan_sp) |
931 | unwind_plan_sp = |
932 | func_unwinders_sp->GetObjectFileUnwindPlan(process->GetTarget()); |
933 | if (unwind_plan_sp && unwind_plan_sp->PlanValidAtAddress(m_current_pc)) { |
934 | UnwindLogMsgVerbose("frame uses %s for full UnwindPlan because the " |
935 | "DynamicLoader suggested we prefer it", |
936 | unwind_plan_sp->GetSourceName().GetCString()); |
937 | return unwind_plan_sp; |
938 | } |
939 | } |
940 | |
941 | // Typically the NonCallSite UnwindPlan is the unwind created by inspecting |
942 | // the assembly language instructions |
943 | if (m_behaves_like_zeroth_frame && process) { |
944 | unwind_plan_sp = func_unwinders_sp->GetUnwindPlanAtNonCallSite( |
945 | process->GetTarget(), m_thread); |
946 | if (unwind_plan_sp && unwind_plan_sp->PlanValidAtAddress(m_current_pc)) { |
947 | if (unwind_plan_sp->GetSourcedFromCompiler() == eLazyBoolNo) { |
948 | // We probably have an UnwindPlan created by inspecting assembly |
949 | // instructions. The assembly profilers work really well with compiler- |
950 | // generated functions but hand- written assembly can be problematic. |
951 | // We set the eh_frame based unwind plan as our fallback unwind plan if |
952 | // instruction emulation doesn't work out even for non call sites if it |
953 | // is available and use the architecture default unwind plan if it is |
954 | // not available. The eh_frame unwind plan is more reliable even on non |
955 | // call sites then the architecture default plan and for hand written |
956 | // assembly code it is often written in a way that it valid at all |
957 | // location what helps in the most common cases when the instruction |
958 | // emulation fails. |
959 | UnwindPlanSP call_site_unwind_plan = |
960 | func_unwinders_sp->GetUnwindPlanAtCallSite(process->GetTarget(), |
961 | m_thread); |
962 | if (call_site_unwind_plan && |
963 | call_site_unwind_plan.get() != unwind_plan_sp.get() && |
964 | call_site_unwind_plan->GetSourceName() != |
965 | unwind_plan_sp->GetSourceName()) { |
966 | m_fallback_unwind_plan_sp = call_site_unwind_plan; |
967 | } else { |
968 | m_fallback_unwind_plan_sp = arch_default_unwind_plan_sp; |
969 | } |
970 | } |
971 | UnwindLogMsgVerbose("frame uses %s for full UnwindPlan because this " |
972 | "is the non-call site unwind plan and this is a " |
973 | "zeroth frame", |
974 | unwind_plan_sp->GetSourceName().GetCString()); |
975 | return unwind_plan_sp; |
976 | } |
977 | |
978 | // If we're on the first instruction of a function, and we have an |
979 | // architectural default UnwindPlan for the initial instruction of a |
980 | // function, use that. |
981 | if (m_current_offset == 0) { |
982 | unwind_plan_sp = |
983 | func_unwinders_sp->GetUnwindPlanArchitectureDefaultAtFunctionEntry( |
984 | m_thread); |
985 | if (unwind_plan_sp) { |
986 | UnwindLogMsgVerbose("frame uses %s for full UnwindPlan because we are at " |
987 | "the first instruction of a function", |
988 | unwind_plan_sp->GetSourceName().GetCString()); |
989 | return unwind_plan_sp; |
990 | } |
991 | } |
992 | } |
993 | |
994 | // Typically this is unwind info from an eh_frame section intended for |
995 | // exception handling; only valid at call sites |
996 | if (process) { |
997 | unwind_plan_sp = func_unwinders_sp->GetUnwindPlanAtCallSite( |
998 | process->GetTarget(), m_thread); |
999 | } |
1000 | int valid_offset = -1; |
1001 | if (IsUnwindPlanValidForCurrentPC(unwind_plan_sp, valid_offset)) { |
1002 | UnwindLogMsgVerbose("frame uses %s for full UnwindPlan because this " |
1003 | "is the call-site unwind plan", |
1004 | unwind_plan_sp->GetSourceName().GetCString()); |
1005 | return unwind_plan_sp; |
1006 | } |
1007 | |
1008 | // We'd prefer to use an UnwindPlan intended for call sites when we're at a |
1009 | // call site but if we've struck out on that, fall back to using the non- |
1010 | // call-site assembly inspection UnwindPlan if possible. |
1011 | if (process) { |
1012 | unwind_plan_sp = func_unwinders_sp->GetUnwindPlanAtNonCallSite( |
1013 | process->GetTarget(), m_thread); |
1014 | } |
1015 | if (unwind_plan_sp && |
1016 | unwind_plan_sp->GetSourcedFromCompiler() == eLazyBoolNo) { |
1017 | // We probably have an UnwindPlan created by inspecting assembly |
1018 | // instructions. The assembly profilers work really well with compiler- |
1019 | // generated functions but hand- written assembly can be problematic. We |
1020 | // set the eh_frame based unwind plan as our fallback unwind plan if |
1021 | // instruction emulation doesn't work out even for non call sites if it is |
1022 | // available and use the architecture default unwind plan if it is not |
1023 | // available. The eh_frame unwind plan is more reliable even on non call |
1024 | // sites then the architecture default plan and for hand written assembly |
1025 | // code it is often written in a way that it valid at all location what |
1026 | // helps in the most common cases when the instruction emulation fails. |
1027 | UnwindPlanSP call_site_unwind_plan = |
1028 | func_unwinders_sp->GetUnwindPlanAtCallSite(process->GetTarget(), |
1029 | m_thread); |
1030 | if (call_site_unwind_plan && |
1031 | call_site_unwind_plan.get() != unwind_plan_sp.get() && |
1032 | call_site_unwind_plan->GetSourceName() != |
1033 | unwind_plan_sp->GetSourceName()) { |
1034 | m_fallback_unwind_plan_sp = call_site_unwind_plan; |
1035 | } else { |
1036 | m_fallback_unwind_plan_sp = arch_default_unwind_plan_sp; |
1037 | } |
1038 | } |
1039 | |
1040 | if (IsUnwindPlanValidForCurrentPC(unwind_plan_sp, valid_offset)) { |
1041 | UnwindLogMsgVerbose("frame uses %s for full UnwindPlan because we " |
1042 | "failed to find a call-site unwind plan that would work", |
1043 | unwind_plan_sp->GetSourceName().GetCString()); |
1044 | return unwind_plan_sp; |
1045 | } |
1046 | |
1047 | // If nothing else, use the architectural default UnwindPlan and hope that |
1048 | // does the job. |
1049 | if (arch_default_unwind_plan_sp) |
1050 | UnwindLogMsgVerbose( |
1051 | "frame uses %s for full UnwindPlan because we are falling back " |
1052 | "to the arch default plan", |
1053 | arch_default_unwind_plan_sp->GetSourceName().GetCString()); |
1054 | else |
1055 | UnwindLogMsg( |
1056 | "Unable to find any UnwindPlan for full unwind of this frame."); |
1057 | |
1058 | return arch_default_unwind_plan_sp; |
1059 | } |
1060 | |
1061 | void RegisterContextUnwind::InvalidateAllRegisters() { |
1062 | m_frame_type = eNotAValidFrame; |
1063 | } |
1064 | |
1065 | size_t RegisterContextUnwind::GetRegisterCount() { |
1066 | return m_thread.GetRegisterContext()->GetRegisterCount(); |
1067 | } |
1068 | |
1069 | const RegisterInfo *RegisterContextUnwind::GetRegisterInfoAtIndex(size_t reg) { |
1070 | return m_thread.GetRegisterContext()->GetRegisterInfoAtIndex(reg); |
1071 | } |
1072 | |
1073 | size_t RegisterContextUnwind::GetRegisterSetCount() { |
1074 | return m_thread.GetRegisterContext()->GetRegisterSetCount(); |
1075 | } |
1076 | |
1077 | const RegisterSet *RegisterContextUnwind::GetRegisterSet(size_t reg_set) { |
1078 | return m_thread.GetRegisterContext()->GetRegisterSet(reg_set); |
1079 | } |
1080 | |
1081 | uint32_t RegisterContextUnwind::ConvertRegisterKindToRegisterNumber( |
1082 | lldb::RegisterKind kind, uint32_t num) { |
1083 | return m_thread.GetRegisterContext()->ConvertRegisterKindToRegisterNumber( |
1084 | kind, num); |
1085 | } |
1086 | |
1087 | bool RegisterContextUnwind::ReadRegisterValueFromRegisterLocation( |
1088 | lldb_private::UnwindLLDB::RegisterLocation regloc, |
1089 | const RegisterInfo *reg_info, RegisterValue &value) { |
1090 | if (!IsValid()) |
1091 | return false; |
1092 | bool success = false; |
1093 | |
1094 | switch (regloc.type) { |
1095 | case UnwindLLDB::RegisterLocation::eRegisterInLiveRegisterContext: { |
1096 | const RegisterInfo *other_reg_info = |
1097 | GetRegisterInfoAtIndex(regloc.location.register_number); |
1098 | |
1099 | if (!other_reg_info) |
1100 | return false; |
1101 | |
1102 | success = |
1103 | m_thread.GetRegisterContext()->ReadRegister(other_reg_info, value); |
1104 | } break; |
1105 | case UnwindLLDB::RegisterLocation::eRegisterInRegister: { |
1106 | const RegisterInfo *other_reg_info = |
1107 | GetRegisterInfoAtIndex(regloc.location.register_number); |
1108 | |
1109 | if (!other_reg_info) |
1110 | return false; |
1111 | |
1112 | if (IsFrameZero()) { |
1113 | success = |
1114 | m_thread.GetRegisterContext()->ReadRegister(other_reg_info, value); |
1115 | } else { |
1116 | success = GetNextFrame()->ReadRegister(other_reg_info, value); |
1117 | } |
1118 | } break; |
1119 | case UnwindLLDB::RegisterLocation::eRegisterValueInferred: |
1120 | success = |
1121 | value.SetUInt(regloc.location.inferred_value, reg_info->byte_size); |
1122 | break; |
1123 | |
1124 | case UnwindLLDB::RegisterLocation::eRegisterNotSaved: |
1125 | break; |
1126 | case UnwindLLDB::RegisterLocation::eRegisterSavedAtHostMemoryLocation: |
1127 | llvm_unreachable("FIXME debugger inferior function call unwind")__builtin_unreachable(); |
1128 | case UnwindLLDB::RegisterLocation::eRegisterSavedAtMemoryLocation: { |
1129 | Status error(ReadRegisterValueFromMemory( |
1130 | reg_info, regloc.location.target_memory_location, reg_info->byte_size, |
1131 | value)); |
1132 | success = error.Success(); |
1133 | } break; |
1134 | default: |
1135 | llvm_unreachable("Unknown RegisterLocation type.")__builtin_unreachable(); |
1136 | } |
1137 | return success; |
1138 | } |
1139 | |
1140 | bool RegisterContextUnwind::WriteRegisterValueToRegisterLocation( |
1141 | lldb_private::UnwindLLDB::RegisterLocation regloc, |
1142 | const RegisterInfo *reg_info, const RegisterValue &value) { |
1143 | if (!IsValid()) |
1144 | return false; |
1145 | |
1146 | bool success = false; |
1147 | |
1148 | switch (regloc.type) { |
1149 | case UnwindLLDB::RegisterLocation::eRegisterInLiveRegisterContext: { |
1150 | const RegisterInfo *other_reg_info = |
1151 | GetRegisterInfoAtIndex(regloc.location.register_number); |
1152 | success = |
1153 | m_thread.GetRegisterContext()->WriteRegister(other_reg_info, value); |
1154 | } break; |
1155 | case UnwindLLDB::RegisterLocation::eRegisterInRegister: { |
1156 | const RegisterInfo *other_reg_info = |
1157 | GetRegisterInfoAtIndex(regloc.location.register_number); |
1158 | if (IsFrameZero()) { |
1159 | success = |
1160 | m_thread.GetRegisterContext()->WriteRegister(other_reg_info, value); |
1161 | } else { |
1162 | success = GetNextFrame()->WriteRegister(other_reg_info, value); |
1163 | } |
1164 | } break; |
1165 | case UnwindLLDB::RegisterLocation::eRegisterValueInferred: |
1166 | case UnwindLLDB::RegisterLocation::eRegisterNotSaved: |
1167 | break; |
1168 | case UnwindLLDB::RegisterLocation::eRegisterSavedAtHostMemoryLocation: |
1169 | llvm_unreachable("FIXME debugger inferior function call unwind")__builtin_unreachable(); |
1170 | case UnwindLLDB::RegisterLocation::eRegisterSavedAtMemoryLocation: { |
1171 | Status error(WriteRegisterValueToMemory( |
1172 | reg_info, regloc.location.target_memory_location, reg_info->byte_size, |
1173 | value)); |
1174 | success = error.Success(); |
1175 | } break; |
1176 | default: |
1177 | llvm_unreachable("Unknown RegisterLocation type.")__builtin_unreachable(); |
1178 | } |
1179 | return success; |
1180 | } |
1181 | |
1182 | bool RegisterContextUnwind::IsValid() const { |
1183 | return m_frame_type != eNotAValidFrame; |
1184 | } |
1185 | |
1186 | // After the final stack frame in a stack walk we'll get one invalid |
1187 | // (eNotAValidFrame) stack frame -- one past the end of the stack walk. But |
1188 | // higher-level code will need to tell the difference between "the unwind plan |
1189 | // below this frame failed" versus "we successfully completed the stack walk" |
1190 | // so this method helps to disambiguate that. |
1191 | |
1192 | bool RegisterContextUnwind::IsTrapHandlerFrame() const { |
1193 | return m_frame_type == eTrapHandlerFrame; |
1194 | } |
1195 | |
1196 | // A skip frame is a bogus frame on the stack -- but one where we're likely to |
1197 | // find a real frame farther |
1198 | // up the stack if we keep looking. It's always the second frame in an unwind |
1199 | // (i.e. the first frame after frame zero) where unwinding can be the |
1200 | // trickiest. Ideally we'll mark up this frame in some way so the user knows |
1201 | // we're displaying bad data and we may have skipped one frame of their real |
1202 | // program in the process of getting back on track. |
1203 | |
1204 | bool RegisterContextUnwind::IsSkipFrame() const { |
1205 | return m_frame_type == eSkipFrame; |
1206 | } |
1207 | |
1208 | bool RegisterContextUnwind::IsTrapHandlerSymbol( |
1209 | lldb_private::Process *process, |
1210 | const lldb_private::SymbolContext &m_sym_ctx) const { |
1211 | PlatformSP platform_sp(process->GetTarget().GetPlatform()); |
1212 | if (platform_sp) { |
1213 | const std::vector<ConstString> trap_handler_names( |
1214 | platform_sp->GetTrapHandlerSymbolNames()); |
1215 | for (ConstString name : trap_handler_names) { |
1216 | if ((m_sym_ctx.function && m_sym_ctx.function->GetName() == name) || |
1217 | (m_sym_ctx.symbol && m_sym_ctx.symbol->GetName() == name)) { |
1218 | return true; |
1219 | } |
1220 | } |
1221 | } |
1222 | const std::vector<ConstString> user_specified_trap_handler_names( |
1223 | m_parent_unwind.GetUserSpecifiedTrapHandlerFunctionNames()); |
1224 | for (ConstString name : user_specified_trap_handler_names) { |
1225 | if ((m_sym_ctx.function && m_sym_ctx.function->GetName() == name) || |
1226 | (m_sym_ctx.symbol && m_sym_ctx.symbol->GetName() == name)) { |
1227 | return true; |
1228 | } |
1229 | } |
1230 | |
1231 | return false; |
1232 | } |
1233 | |
1234 | // Answer the question: Where did THIS frame save the CALLER frame ("previous" |
1235 | // frame)'s register value? |
1236 | |
1237 | enum UnwindLLDB::RegisterSearchResult |
1238 | RegisterContextUnwind::SavedLocationForRegister( |
1239 | uint32_t lldb_regnum, lldb_private::UnwindLLDB::RegisterLocation ®loc) { |
1240 | RegisterNumber regnum(m_thread, eRegisterKindLLDB, lldb_regnum); |
1241 | Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND(1u << 15))); |
1242 | |
1243 | // Have we already found this register location? |
1244 | if (!m_registers.empty()) { |
1245 | std::map<uint32_t, |
1246 | lldb_private::UnwindLLDB::RegisterLocation>::const_iterator |
1247 | iterator; |
1248 | iterator = m_registers.find(regnum.GetAsKind(eRegisterKindLLDB)); |
1249 | if (iterator != m_registers.end()) { |
1250 | regloc = iterator->second; |
1251 | UnwindLogMsg("supplying caller's saved %s (%d)'s location, cached", |
1252 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1253 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1254 | } |
1255 | } |
1256 | |
1257 | // Look through the available UnwindPlans for the register location. |
1258 | |
1259 | UnwindPlan::Row::RegisterLocation unwindplan_regloc; |
1260 | bool have_unwindplan_regloc = false; |
1261 | RegisterKind unwindplan_registerkind = kNumRegisterKinds; |
1262 | |
1263 | if (m_fast_unwind_plan_sp) { |
1264 | UnwindPlan::RowSP active_row = |
1265 | m_fast_unwind_plan_sp->GetRowForFunctionOffset(m_current_offset); |
1266 | unwindplan_registerkind = m_fast_unwind_plan_sp->GetRegisterKind(); |
1267 | if (regnum.GetAsKind(unwindplan_registerkind) == LLDB_INVALID_REGNUM0xffffffffU) { |
1268 | UnwindLogMsg("could not convert lldb regnum %s (%d) into %d RegisterKind " |
1269 | "reg numbering scheme", |
1270 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB), |
1271 | (int)unwindplan_registerkind); |
1272 | return UnwindLLDB::RegisterSearchResult::eRegisterNotFound; |
1273 | } |
1274 | // The architecture default unwind plan marks unknown registers as |
1275 | // Undefined so that we don't forward them up the stack when a |
1276 | // jitted stack frame may have overwritten them. But when the |
1277 | // arch default unwind plan is used as the Fast Unwind Plan, we |
1278 | // need to recognize this & switch over to the Full Unwind Plan |
1279 | // to see what unwind rule that (more knoweldgeable, probably) |
1280 | // UnwindPlan has. If the full UnwindPlan says the register |
1281 | // location is Undefined, then it really is. |
1282 | if (active_row->GetRegisterInfo(regnum.GetAsKind(unwindplan_registerkind), |
1283 | unwindplan_regloc) && |
1284 | !unwindplan_regloc.IsUndefined()) { |
1285 | UnwindLogMsg( |
1286 | "supplying caller's saved %s (%d)'s location using FastUnwindPlan", |
1287 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1288 | have_unwindplan_regloc = true; |
1289 | } |
1290 | } |
1291 | |
1292 | if (!have_unwindplan_regloc) { |
1293 | // m_full_unwind_plan_sp being NULL means that we haven't tried to find a |
1294 | // full UnwindPlan yet |
1295 | bool got_new_full_unwindplan = false; |
1296 | if (!m_full_unwind_plan_sp) { |
1297 | m_full_unwind_plan_sp = GetFullUnwindPlanForFrame(); |
1298 | got_new_full_unwindplan = true; |
1299 | } |
1300 | |
1301 | if (m_full_unwind_plan_sp) { |
1302 | RegisterNumber pc_regnum(m_thread, eRegisterKindGeneric, |
1303 | LLDB_REGNUM_GENERIC_PC0); |
1304 | |
1305 | UnwindPlan::RowSP active_row = |
1306 | m_full_unwind_plan_sp->GetRowForFunctionOffset(m_current_offset); |
1307 | unwindplan_registerkind = m_full_unwind_plan_sp->GetRegisterKind(); |
1308 | |
1309 | if (got_new_full_unwindplan && active_row.get() && log) { |
1310 | StreamString active_row_strm; |
1311 | ExecutionContext exe_ctx(m_thread.shared_from_this()); |
1312 | active_row->Dump(active_row_strm, m_full_unwind_plan_sp.get(), |
1313 | &m_thread, |
1314 | m_start_pc.GetLoadAddress(exe_ctx.GetTargetPtr())); |
1315 | UnwindLogMsg("Using full unwind plan '%s'", |
1316 | m_full_unwind_plan_sp->GetSourceName().AsCString()); |
1317 | UnwindLogMsg("active row: %s", active_row_strm.GetData()); |
1318 | } |
1319 | RegisterNumber return_address_reg; |
1320 | |
1321 | // If we're fetching the saved pc and this UnwindPlan defines a |
1322 | // ReturnAddress register (e.g. lr on arm), look for the return address |
1323 | // register number in the UnwindPlan's row. |
1324 | if (pc_regnum.IsValid() && pc_regnum == regnum && |
1325 | m_full_unwind_plan_sp->GetReturnAddressRegister() != |
1326 | LLDB_INVALID_REGNUM0xffffffffU) { |
1327 | // If this is a trap handler frame, we should have access to |
1328 | // the complete register context when the interrupt/async |
1329 | // signal was received, we should fetch the actual saved $pc |
1330 | // value instead of the Return Address register. |
1331 | // If $pc is not available, fall back to the RA reg. |
1332 | UnwindPlan::Row::RegisterLocation scratch; |
1333 | if (m_frame_type == eTrapHandlerFrame && |
1334 | active_row->GetRegisterInfo |
1335 | (pc_regnum.GetAsKind (unwindplan_registerkind), scratch)) { |
1336 | UnwindLogMsg("Providing pc register instead of rewriting to " |
1337 | "RA reg because this is a trap handler and there is " |
1338 | "a location for the saved pc register value."); |
1339 | } else { |
1340 | return_address_reg.init( |
1341 | m_thread, m_full_unwind_plan_sp->GetRegisterKind(), |
1342 | m_full_unwind_plan_sp->GetReturnAddressRegister()); |
1343 | regnum = return_address_reg; |
1344 | UnwindLogMsg("requested caller's saved PC but this UnwindPlan uses a " |
1345 | "RA reg; getting %s (%d) instead", |
1346 | return_address_reg.GetName(), |
1347 | return_address_reg.GetAsKind(eRegisterKindLLDB)); |
1348 | } |
1349 | } else { |
1350 | if (regnum.GetAsKind(unwindplan_registerkind) == LLDB_INVALID_REGNUM0xffffffffU) { |
1351 | if (unwindplan_registerkind == eRegisterKindGeneric) { |
1352 | UnwindLogMsg("could not convert lldb regnum %s (%d) into " |
1353 | "eRegisterKindGeneric reg numbering scheme", |
1354 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1355 | } else { |
1356 | UnwindLogMsg("could not convert lldb regnum %s (%d) into %d " |
1357 | "RegisterKind reg numbering scheme", |
1358 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB), |
1359 | (int)unwindplan_registerkind); |
1360 | } |
1361 | return UnwindLLDB::RegisterSearchResult::eRegisterNotFound; |
1362 | } |
1363 | } |
1364 | |
1365 | if (regnum.IsValid() && |
1366 | active_row->GetRegisterInfo(regnum.GetAsKind(unwindplan_registerkind), |
1367 | unwindplan_regloc)) { |
1368 | have_unwindplan_regloc = true; |
1369 | UnwindLogMsg( |
1370 | "supplying caller's saved %s (%d)'s location using %s UnwindPlan", |
1371 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB), |
1372 | m_full_unwind_plan_sp->GetSourceName().GetCString()); |
1373 | } |
1374 | |
1375 | // This is frame 0 and we're retrieving the PC and it's saved in a Return |
1376 | // Address register and it hasn't been saved anywhere yet -- that is, |
1377 | // it's still live in the actual register. Handle this specially. |
1378 | |
1379 | if (!have_unwindplan_regloc && return_address_reg.IsValid() && |
1380 | IsFrameZero()) { |
1381 | if (return_address_reg.GetAsKind(eRegisterKindLLDB) != |
1382 | LLDB_INVALID_REGNUM0xffffffffU) { |
1383 | lldb_private::UnwindLLDB::RegisterLocation new_regloc; |
1384 | new_regloc.type = |
1385 | UnwindLLDB::RegisterLocation::eRegisterInLiveRegisterContext; |
1386 | new_regloc.location.register_number = |
1387 | return_address_reg.GetAsKind(eRegisterKindLLDB); |
1388 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = new_regloc; |
1389 | regloc = new_regloc; |
1390 | UnwindLogMsg("supplying caller's register %s (%d) from the live " |
1391 | "RegisterContext at frame 0, saved in %d", |
1392 | return_address_reg.GetName(), |
1393 | return_address_reg.GetAsKind(eRegisterKindLLDB), |
1394 | return_address_reg.GetAsKind(eRegisterKindLLDB)); |
1395 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1396 | } |
1397 | } |
1398 | |
1399 | // If this architecture stores the return address in a register (it |
1400 | // defines a Return Address register) and we're on a non-zero stack frame |
1401 | // and the Full UnwindPlan says that the pc is stored in the |
1402 | // RA registers (e.g. lr on arm), then we know that the full unwindplan is |
1403 | // not trustworthy -- this |
1404 | // is an impossible situation and the instruction emulation code has |
1405 | // likely been misled. If this stack frame meets those criteria, we need |
1406 | // to throw away the Full UnwindPlan that the instruction emulation came |
1407 | // up with and fall back to the architecture's Default UnwindPlan so the |
1408 | // stack walk can get past this point. |
1409 | |
1410 | // Special note: If the Full UnwindPlan was generated from the compiler, |
1411 | // don't second-guess it when we're at a call site location. |
1412 | |
1413 | // arch_default_ra_regnum is the return address register # in the Full |
1414 | // UnwindPlan register numbering |
1415 | RegisterNumber arch_default_ra_regnum(m_thread, eRegisterKindGeneric, |
1416 | LLDB_REGNUM_GENERIC_RA3); |
1417 | |
1418 | if (arch_default_ra_regnum.GetAsKind(unwindplan_registerkind) != |
1419 | LLDB_INVALID_REGNUM0xffffffffU && |
1420 | pc_regnum == regnum && unwindplan_regloc.IsInOtherRegister() && |
1421 | unwindplan_regloc.GetRegisterNumber() == |
1422 | arch_default_ra_regnum.GetAsKind(unwindplan_registerkind) && |
1423 | m_full_unwind_plan_sp->GetSourcedFromCompiler() != eLazyBoolYes && |
1424 | !m_all_registers_available) { |
1425 | UnwindLogMsg("%s UnwindPlan tried to restore the pc from the link " |
1426 | "register but this is a non-zero frame", |
1427 | m_full_unwind_plan_sp->GetSourceName().GetCString()); |
1428 | |
1429 | // Throw away the full unwindplan; install the arch default unwindplan |
1430 | if (ForceSwitchToFallbackUnwindPlan()) { |
1431 | // Update for the possibly new unwind plan |
1432 | unwindplan_registerkind = m_full_unwind_plan_sp->GetRegisterKind(); |
1433 | UnwindPlan::RowSP active_row = |
1434 | m_full_unwind_plan_sp->GetRowForFunctionOffset(m_current_offset); |
1435 | |
1436 | // Sanity check: Verify that we can fetch a pc value and CFA value |
1437 | // with this unwind plan |
1438 | |
1439 | RegisterNumber arch_default_pc_reg(m_thread, eRegisterKindGeneric, |
1440 | LLDB_REGNUM_GENERIC_PC0); |
1441 | bool can_fetch_pc_value = false; |
1442 | bool can_fetch_cfa = false; |
1443 | addr_t cfa_value; |
1444 | if (active_row) { |
1445 | if (arch_default_pc_reg.GetAsKind(unwindplan_registerkind) != |
1446 | LLDB_INVALID_REGNUM0xffffffffU && |
1447 | active_row->GetRegisterInfo( |
1448 | arch_default_pc_reg.GetAsKind(unwindplan_registerkind), |
1449 | unwindplan_regloc)) { |
1450 | can_fetch_pc_value = true; |
1451 | } |
1452 | if (ReadFrameAddress(unwindplan_registerkind, |
1453 | active_row->GetCFAValue(), cfa_value)) { |
1454 | can_fetch_cfa = true; |
1455 | } |
1456 | } |
1457 | |
1458 | have_unwindplan_regloc = can_fetch_pc_value && can_fetch_cfa; |
1459 | } else { |
1460 | // We were unable to fall back to another unwind plan |
1461 | have_unwindplan_regloc = false; |
1462 | } |
1463 | } |
1464 | } |
1465 | } |
1466 | |
1467 | ExecutionContext exe_ctx(m_thread.shared_from_this()); |
1468 | Process *process = exe_ctx.GetProcessPtr(); |
1469 | if (!have_unwindplan_regloc) { |
1470 | // If the UnwindPlan failed to give us an unwind location for this |
1471 | // register, we may be able to fall back to some ABI-defined default. For |
1472 | // example, some ABIs allow to determine the caller's SP via the CFA. Also, |
1473 | // the ABI may set volatile registers to the undefined state. |
1474 | ABI *abi = process ? process->GetABI().get() : nullptr; |
1475 | if (abi) { |
1476 | const RegisterInfo *reg_info = |
1477 | GetRegisterInfoAtIndex(regnum.GetAsKind(eRegisterKindLLDB)); |
1478 | if (reg_info && |
1479 | abi->GetFallbackRegisterLocation(reg_info, unwindplan_regloc)) { |
1480 | UnwindLogMsg( |
1481 | "supplying caller's saved %s (%d)'s location using ABI default", |
1482 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1483 | have_unwindplan_regloc = true; |
1484 | } |
1485 | } |
1486 | } |
1487 | |
1488 | if (!have_unwindplan_regloc) { |
1489 | if (IsFrameZero()) { |
1490 | // This is frame 0 - we should return the actual live register context |
1491 | // value |
1492 | lldb_private::UnwindLLDB::RegisterLocation new_regloc; |
1493 | new_regloc.type = |
1494 | UnwindLLDB::RegisterLocation::eRegisterInLiveRegisterContext; |
1495 | new_regloc.location.register_number = regnum.GetAsKind(eRegisterKindLLDB); |
1496 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = new_regloc; |
1497 | regloc = new_regloc; |
1498 | UnwindLogMsg("supplying caller's register %s (%d) from the live " |
1499 | "RegisterContext at frame 0", |
1500 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1501 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1502 | } else { |
1503 | std::string unwindplan_name(""); |
1504 | if (m_full_unwind_plan_sp) { |
1505 | unwindplan_name += "via '"; |
1506 | unwindplan_name += m_full_unwind_plan_sp->GetSourceName().AsCString(); |
1507 | unwindplan_name += "'"; |
1508 | } |
1509 | UnwindLogMsg("no save location for %s (%d) %s", regnum.GetName(), |
1510 | regnum.GetAsKind(eRegisterKindLLDB), |
1511 | unwindplan_name.c_str()); |
1512 | } |
1513 | return UnwindLLDB::RegisterSearchResult::eRegisterNotFound; |
1514 | } |
1515 | |
1516 | // unwindplan_regloc has valid contents about where to retrieve the register |
1517 | if (unwindplan_regloc.IsUnspecified()) { |
1518 | lldb_private::UnwindLLDB::RegisterLocation new_regloc; |
1519 | new_regloc.type = UnwindLLDB::RegisterLocation::eRegisterNotSaved; |
1520 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = new_regloc; |
1521 | UnwindLogMsg("save location for %s (%d) is unspecified, continue searching", |
1522 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1523 | return UnwindLLDB::RegisterSearchResult::eRegisterNotFound; |
1524 | } |
1525 | |
1526 | if (unwindplan_regloc.IsUndefined()) { |
1527 | UnwindLogMsg( |
1528 | "did not supply reg location for %s (%d) because it is volatile", |
1529 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1530 | return UnwindLLDB::RegisterSearchResult::eRegisterIsVolatile; |
1531 | } |
1532 | |
1533 | if (unwindplan_regloc.IsSame()) { |
1534 | if (!IsFrameZero() && |
1535 | (regnum.GetAsKind(eRegisterKindGeneric) == LLDB_REGNUM_GENERIC_PC0 || |
1536 | regnum.GetAsKind(eRegisterKindGeneric) == LLDB_REGNUM_GENERIC_RA3)) { |
1537 | UnwindLogMsg("register %s (%d) is marked as 'IsSame' - it is a pc or " |
1538 | "return address reg on a non-zero frame -- treat as if we " |
1539 | "have no information", |
1540 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1541 | return UnwindLLDB::RegisterSearchResult::eRegisterNotFound; |
1542 | } else { |
1543 | regloc.type = UnwindLLDB::RegisterLocation::eRegisterInRegister; |
1544 | regloc.location.register_number = regnum.GetAsKind(eRegisterKindLLDB); |
1545 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = regloc; |
1546 | UnwindLogMsg( |
1547 | "supplying caller's register %s (%d), saved in register %s (%d)", |
1548 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB), |
1549 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1550 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1551 | } |
1552 | } |
1553 | |
1554 | if (unwindplan_regloc.IsCFAPlusOffset()) { |
1555 | int offset = unwindplan_regloc.GetOffset(); |
1556 | regloc.type = UnwindLLDB::RegisterLocation::eRegisterValueInferred; |
1557 | regloc.location.inferred_value = m_cfa + offset; |
1558 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = regloc; |
1559 | UnwindLogMsg("supplying caller's register %s (%d), value is CFA plus " |
1560 | "offset %d [value is 0x%" PRIx64"llx" "]", |
1561 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB), offset, |
1562 | regloc.location.inferred_value); |
1563 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1564 | } |
1565 | |
1566 | if (unwindplan_regloc.IsAtCFAPlusOffset()) { |
1567 | int offset = unwindplan_regloc.GetOffset(); |
1568 | regloc.type = UnwindLLDB::RegisterLocation::eRegisterSavedAtMemoryLocation; |
1569 | regloc.location.target_memory_location = m_cfa + offset; |
1570 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = regloc; |
1571 | UnwindLogMsg("supplying caller's register %s (%d) from the stack, saved at " |
1572 | "CFA plus offset %d [saved at 0x%" PRIx64"llx" "]", |
1573 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB), offset, |
1574 | regloc.location.target_memory_location); |
1575 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1576 | } |
1577 | |
1578 | if (unwindplan_regloc.IsAFAPlusOffset()) { |
1579 | if (m_afa == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) |
1580 | return UnwindLLDB::RegisterSearchResult::eRegisterNotFound; |
1581 | |
1582 | int offset = unwindplan_regloc.GetOffset(); |
1583 | regloc.type = UnwindLLDB::RegisterLocation::eRegisterValueInferred; |
1584 | regloc.location.inferred_value = m_afa + offset; |
1585 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = regloc; |
1586 | UnwindLogMsg("supplying caller's register %s (%d), value is AFA plus " |
1587 | "offset %d [value is 0x%" PRIx64"llx" "]", |
1588 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB), offset, |
1589 | regloc.location.inferred_value); |
1590 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1591 | } |
1592 | |
1593 | if (unwindplan_regloc.IsAtAFAPlusOffset()) { |
1594 | if (m_afa == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) |
1595 | return UnwindLLDB::RegisterSearchResult::eRegisterNotFound; |
1596 | |
1597 | int offset = unwindplan_regloc.GetOffset(); |
1598 | regloc.type = UnwindLLDB::RegisterLocation::eRegisterSavedAtMemoryLocation; |
1599 | regloc.location.target_memory_location = m_afa + offset; |
1600 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = regloc; |
1601 | UnwindLogMsg("supplying caller's register %s (%d) from the stack, saved at " |
1602 | "AFA plus offset %d [saved at 0x%" PRIx64"llx" "]", |
1603 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB), offset, |
1604 | regloc.location.target_memory_location); |
1605 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1606 | } |
1607 | |
1608 | if (unwindplan_regloc.IsInOtherRegister()) { |
1609 | uint32_t unwindplan_regnum = unwindplan_regloc.GetRegisterNumber(); |
1610 | RegisterNumber row_regnum(m_thread, unwindplan_registerkind, |
1611 | unwindplan_regnum); |
1612 | if (row_regnum.GetAsKind(eRegisterKindLLDB) == LLDB_INVALID_REGNUM0xffffffffU) { |
1613 | UnwindLogMsg("could not supply caller's %s (%d) location - was saved in " |
1614 | "another reg but couldn't convert that regnum", |
1615 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1616 | return UnwindLLDB::RegisterSearchResult::eRegisterNotFound; |
1617 | } |
1618 | regloc.type = UnwindLLDB::RegisterLocation::eRegisterInRegister; |
1619 | regloc.location.register_number = row_regnum.GetAsKind(eRegisterKindLLDB); |
1620 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = regloc; |
1621 | UnwindLogMsg( |
1622 | "supplying caller's register %s (%d), saved in register %s (%d)", |
1623 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB), |
1624 | row_regnum.GetName(), row_regnum.GetAsKind(eRegisterKindLLDB)); |
1625 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1626 | } |
1627 | |
1628 | if (unwindplan_regloc.IsDWARFExpression() || |
1629 | unwindplan_regloc.IsAtDWARFExpression()) { |
1630 | DataExtractor dwarfdata(unwindplan_regloc.GetDWARFExpressionBytes(), |
1631 | unwindplan_regloc.GetDWARFExpressionLength(), |
1632 | process->GetByteOrder(), |
1633 | process->GetAddressByteSize()); |
1634 | ModuleSP opcode_ctx; |
1635 | DWARFExpression dwarfexpr(opcode_ctx, dwarfdata, nullptr); |
1636 | dwarfexpr.SetRegisterKind(unwindplan_registerkind); |
1637 | Value cfa_val = Scalar(m_cfa); |
1638 | cfa_val.SetValueType(Value::ValueType::LoadAddress); |
1639 | Value result; |
1640 | Status error; |
1641 | if (dwarfexpr.Evaluate(&exe_ctx, this, 0, &cfa_val, nullptr, result, |
1642 | &error)) { |
1643 | addr_t val; |
1644 | val = result.GetScalar().ULongLong(); |
1645 | if (unwindplan_regloc.IsDWARFExpression()) { |
1646 | regloc.type = UnwindLLDB::RegisterLocation::eRegisterValueInferred; |
1647 | regloc.location.inferred_value = val; |
1648 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = regloc; |
1649 | UnwindLogMsg("supplying caller's register %s (%d) via DWARF expression " |
1650 | "(IsDWARFExpression)", |
1651 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1652 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1653 | } else { |
1654 | regloc.type = |
1655 | UnwindLLDB::RegisterLocation::eRegisterSavedAtMemoryLocation; |
1656 | regloc.location.target_memory_location = val; |
1657 | m_registers[regnum.GetAsKind(eRegisterKindLLDB)] = regloc; |
1658 | UnwindLogMsg("supplying caller's register %s (%d) via DWARF expression " |
1659 | "(IsAtDWARFExpression)", |
1660 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1661 | return UnwindLLDB::RegisterSearchResult::eRegisterFound; |
1662 | } |
1663 | } |
1664 | UnwindLogMsg("tried to use IsDWARFExpression or IsAtDWARFExpression for %s " |
1665 | "(%d) but failed", |
1666 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1667 | return UnwindLLDB::RegisterSearchResult::eRegisterNotFound; |
1668 | } |
1669 | |
1670 | UnwindLogMsg("no save location for %s (%d) in this stack frame", |
1671 | regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB)); |
1672 | |
1673 | // FIXME UnwindPlan::Row types atDWARFExpression and isDWARFExpression are |
1674 | // unsupported. |
1675 | |
1676 | return UnwindLLDB::RegisterSearchResult::eRegisterNotFound; |
1677 | } |
1678 | |
1679 | // TryFallbackUnwindPlan() -- this method is a little tricky. |
1680 | // |
1681 | // When this is called, the frame above -- the caller frame, the "previous" |
1682 | // frame -- is invalid or bad. |
1683 | // |
1684 | // Instead of stopping the stack walk here, we'll try a different UnwindPlan |
1685 | // and see if we can get a valid frame above us. |
1686 | // |
1687 | // This most often happens when an unwind plan based on assembly instruction |
1688 | // inspection is not correct -- mostly with hand-written assembly functions or |
1689 | // functions where the stack frame is set up "out of band", e.g. the kernel |
1690 | // saved the register context and then called an asynchronous trap handler like |
1691 | // _sigtramp. |
1692 | // |
1693 | // Often in these cases, if we just do a dumb stack walk we'll get past this |
1694 | // tricky frame and our usual techniques can continue to be used. |
1695 | |
1696 | bool RegisterContextUnwind::TryFallbackUnwindPlan() { |
1697 | if (m_fallback_unwind_plan_sp.get() == nullptr) |
1698 | return false; |
1699 | |
1700 | if (m_full_unwind_plan_sp.get() == nullptr) |
1701 | return false; |
1702 | |
1703 | if (m_full_unwind_plan_sp.get() == m_fallback_unwind_plan_sp.get() || |
1704 | m_full_unwind_plan_sp->GetSourceName() == |
1705 | m_fallback_unwind_plan_sp->GetSourceName()) { |
1706 | return false; |
1707 | } |
1708 | |
1709 | // If a compiler generated unwind plan failed, trying the arch default |
1710 | // unwindplan isn't going to do any better. |
1711 | if (m_full_unwind_plan_sp->GetSourcedFromCompiler() == eLazyBoolYes) |
1712 | return false; |
1713 | |
1714 | // Get the caller's pc value and our own CFA value. Swap in the fallback |
1715 | // unwind plan, re-fetch the caller's pc value and CFA value. If they're the |
1716 | // same, then the fallback unwind plan provides no benefit. |
1717 | |
1718 | RegisterNumber pc_regnum(m_thread, eRegisterKindGeneric, |
1719 | LLDB_REGNUM_GENERIC_PC0); |
1720 | |
1721 | addr_t old_caller_pc_value = LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
1722 | addr_t new_caller_pc_value = LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
1723 | UnwindLLDB::RegisterLocation regloc; |
1724 | if (SavedLocationForRegister(pc_regnum.GetAsKind(eRegisterKindLLDB), |
1725 | regloc) == |
1726 | UnwindLLDB::RegisterSearchResult::eRegisterFound) { |
1727 | const RegisterInfo *reg_info = |
1728 | GetRegisterInfoAtIndex(pc_regnum.GetAsKind(eRegisterKindLLDB)); |
1729 | if (reg_info) { |
1730 | RegisterValue reg_value; |
1731 | if (ReadRegisterValueFromRegisterLocation(regloc, reg_info, reg_value)) { |
1732 | old_caller_pc_value = reg_value.GetAsUInt64(); |
1733 | if (ProcessSP process_sp = m_thread.GetProcess()) { |
1734 | if (ABISP abi = process_sp->GetABI()) |
1735 | old_caller_pc_value = abi->FixCodeAddress(old_caller_pc_value); |
1736 | } |
1737 | } |
1738 | } |
1739 | } |
1740 | |
1741 | // This is a tricky wrinkle! If SavedLocationForRegister() detects a really |
1742 | // impossible register location for the full unwind plan, it may call |
1743 | // ForceSwitchToFallbackUnwindPlan() which in turn replaces the full |
1744 | // unwindplan with the fallback... in short, we're done, we're using the |
1745 | // fallback UnwindPlan. We checked if m_fallback_unwind_plan_sp was nullptr |
1746 | // at the top -- the only way it became nullptr since then is via |
1747 | // SavedLocationForRegister(). |
1748 | if (m_fallback_unwind_plan_sp.get() == nullptr) |
1749 | return true; |
1750 | |
1751 | // Switch the full UnwindPlan to be the fallback UnwindPlan. If we decide |
1752 | // this isn't working, we need to restore. We'll also need to save & restore |
1753 | // the value of the m_cfa ivar. Save is down below a bit in 'old_cfa'. |
1754 | UnwindPlanSP original_full_unwind_plan_sp = m_full_unwind_plan_sp; |
1755 | addr_t old_cfa = m_cfa; |
1756 | addr_t old_afa = m_afa; |
1757 | |
1758 | m_registers.clear(); |
1759 | |
1760 | m_full_unwind_plan_sp = m_fallback_unwind_plan_sp; |
1761 | |
1762 | UnwindPlan::RowSP active_row = |
1763 | m_fallback_unwind_plan_sp->GetRowForFunctionOffset(m_current_offset); |
1764 | |
1765 | if (active_row && |
1766 | active_row->GetCFAValue().GetValueType() != |
1767 | UnwindPlan::Row::FAValue::unspecified) { |
1768 | addr_t new_cfa; |
1769 | if (!ReadFrameAddress(m_fallback_unwind_plan_sp->GetRegisterKind(), |
1770 | active_row->GetCFAValue(), new_cfa) || |
1771 | new_cfa == 0 || new_cfa == 1 || new_cfa == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
1772 | UnwindLogMsg("failed to get cfa with fallback unwindplan"); |
1773 | m_fallback_unwind_plan_sp.reset(); |
1774 | m_full_unwind_plan_sp = original_full_unwind_plan_sp; |
1775 | return false; |
1776 | } |
1777 | m_cfa = new_cfa; |
1778 | |
1779 | ReadFrameAddress(m_fallback_unwind_plan_sp->GetRegisterKind(), |
1780 | active_row->GetAFAValue(), m_afa); |
1781 | |
1782 | if (SavedLocationForRegister(pc_regnum.GetAsKind(eRegisterKindLLDB), |
1783 | regloc) == |
1784 | UnwindLLDB::RegisterSearchResult::eRegisterFound) { |
1785 | const RegisterInfo *reg_info = |
1786 | GetRegisterInfoAtIndex(pc_regnum.GetAsKind(eRegisterKindLLDB)); |
1787 | if (reg_info) { |
1788 | RegisterValue reg_value; |
1789 | if (ReadRegisterValueFromRegisterLocation(regloc, reg_info, |
1790 | reg_value)) { |
1791 | new_caller_pc_value = reg_value.GetAsUInt64(); |
1792 | if (ProcessSP process_sp = m_thread.GetProcess()) { |
1793 | if (ABISP abi = process_sp->GetABI()) |
1794 | new_caller_pc_value = abi->FixCodeAddress(new_caller_pc_value); |
1795 | } |
1796 | } |
1797 | } |
1798 | } |
1799 | |
1800 | if (new_caller_pc_value == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
1801 | UnwindLogMsg("failed to get a pc value for the caller frame with the " |
1802 | "fallback unwind plan"); |
1803 | m_fallback_unwind_plan_sp.reset(); |
1804 | m_full_unwind_plan_sp = original_full_unwind_plan_sp; |
1805 | m_cfa = old_cfa; |
1806 | m_afa = old_afa; |
1807 | return false; |
1808 | } |
1809 | |
1810 | if (old_caller_pc_value == new_caller_pc_value && |
1811 | m_cfa == old_cfa && |
1812 | m_afa == old_afa) { |
1813 | UnwindLogMsg("fallback unwind plan got the same values for this frame " |
1814 | "CFA and caller frame pc, not using"); |
1815 | m_fallback_unwind_plan_sp.reset(); |
1816 | m_full_unwind_plan_sp = original_full_unwind_plan_sp; |
1817 | return false; |
1818 | } |
1819 | |
1820 | UnwindLogMsg("trying to unwind from this function with the UnwindPlan '%s' " |
1821 | "because UnwindPlan '%s' failed.", |
1822 | m_fallback_unwind_plan_sp->GetSourceName().GetCString(), |
1823 | original_full_unwind_plan_sp->GetSourceName().GetCString()); |
1824 | |
1825 | // We've copied the fallback unwind plan into the full - now clear the |
1826 | // fallback. |
1827 | m_fallback_unwind_plan_sp.reset(); |
1828 | PropagateTrapHandlerFlagFromUnwindPlan(m_full_unwind_plan_sp); |
1829 | } |
1830 | |
1831 | return true; |
1832 | } |
1833 | |
1834 | bool RegisterContextUnwind::ForceSwitchToFallbackUnwindPlan() { |
1835 | if (m_fallback_unwind_plan_sp.get() == nullptr) |
1836 | return false; |
1837 | |
1838 | if (m_full_unwind_plan_sp.get() == nullptr) |
1839 | return false; |
1840 | |
1841 | if (m_full_unwind_plan_sp.get() == m_fallback_unwind_plan_sp.get() || |
1842 | m_full_unwind_plan_sp->GetSourceName() == |
1843 | m_fallback_unwind_plan_sp->GetSourceName()) { |
1844 | return false; |
1845 | } |
1846 | |
1847 | UnwindPlan::RowSP active_row = |
1848 | m_fallback_unwind_plan_sp->GetRowForFunctionOffset(m_current_offset); |
1849 | |
1850 | if (active_row && |
1851 | active_row->GetCFAValue().GetValueType() != |
1852 | UnwindPlan::Row::FAValue::unspecified) { |
1853 | addr_t new_cfa; |
1854 | if (!ReadFrameAddress(m_fallback_unwind_plan_sp->GetRegisterKind(), |
1855 | active_row->GetCFAValue(), new_cfa) || |
1856 | new_cfa == 0 || new_cfa == 1 || new_cfa == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
1857 | UnwindLogMsg("failed to get cfa with fallback unwindplan"); |
1858 | m_fallback_unwind_plan_sp.reset(); |
1859 | return false; |
1860 | } |
1861 | |
1862 | ReadFrameAddress(m_fallback_unwind_plan_sp->GetRegisterKind(), |
1863 | active_row->GetAFAValue(), m_afa); |
1864 | |
1865 | m_full_unwind_plan_sp = m_fallback_unwind_plan_sp; |
1866 | m_fallback_unwind_plan_sp.reset(); |
1867 | |
1868 | m_registers.clear(); |
1869 | |
1870 | m_cfa = new_cfa; |
1871 | |
1872 | PropagateTrapHandlerFlagFromUnwindPlan(m_full_unwind_plan_sp); |
1873 | |
1874 | UnwindLogMsg("switched unconditionally to the fallback unwindplan %s", |
1875 | m_full_unwind_plan_sp->GetSourceName().GetCString()); |
1876 | return true; |
1877 | } |
1878 | return false; |
1879 | } |
1880 | |
1881 | void RegisterContextUnwind::PropagateTrapHandlerFlagFromUnwindPlan( |
1882 | lldb::UnwindPlanSP unwind_plan) { |
1883 | if (unwind_plan->GetUnwindPlanForSignalTrap() != eLazyBoolYes) { |
1884 | // Unwind plan does not indicate trap handler. Do nothing. We may |
1885 | // already be flagged as trap handler flag due to the symbol being |
1886 | // in the trap handler symbol list, and that should take precedence. |
1887 | return; |
1888 | } else if (m_frame_type != eNormalFrame) { |
1889 | // If this is already a trap handler frame, nothing to do. |
1890 | // If this is a skip or debug or invalid frame, don't override that. |
1891 | return; |
1892 | } |
1893 | |
1894 | m_frame_type = eTrapHandlerFrame; |
1895 | |
1896 | if (m_current_offset_backed_up_one != m_current_offset) { |
1897 | // We backed up the pc by 1 to compute the symbol context, but |
1898 | // now need to undo that because the pc of the trap handler |
1899 | // frame may in fact be the first instruction of a signal return |
1900 | // trampoline, rather than the instruction after a call. This |
1901 | // happens on systems where the signal handler dispatch code, rather |
1902 | // than calling the handler and being returned to, jumps to the |
1903 | // handler after pushing the address of a return trampoline on the |
1904 | // stack -- on these systems, when the handler returns, control will |
1905 | // be transferred to the return trampoline, so that's the best |
1906 | // symbol we can present in the callstack. |
1907 | UnwindLogMsg("Resetting current offset and re-doing symbol lookup; " |
1908 | "old symbol was %s", |
1909 | GetSymbolOrFunctionName(m_sym_ctx).AsCString("")); |
1910 | m_current_offset_backed_up_one = m_current_offset; |
1911 | |
1912 | AddressRange addr_range; |
1913 | m_sym_ctx_valid = m_current_pc.ResolveFunctionScope(m_sym_ctx, &addr_range); |
1914 | |
1915 | UnwindLogMsg("Symbol is now %s", |
1916 | GetSymbolOrFunctionName(m_sym_ctx).AsCString("")); |
1917 | |
1918 | ExecutionContext exe_ctx(m_thread.shared_from_this()); |
1919 | Process *process = exe_ctx.GetProcessPtr(); |
1920 | Target *target = &process->GetTarget(); |
1921 | |
1922 | m_start_pc = addr_range.GetBaseAddress(); |
1923 | m_current_offset = |
1924 | m_current_pc.GetLoadAddress(target) - m_start_pc.GetLoadAddress(target); |
1925 | } |
1926 | } |
1927 | |
1928 | bool RegisterContextUnwind::ReadFrameAddress( |
1929 | lldb::RegisterKind row_register_kind, UnwindPlan::Row::FAValue &fa, |
1930 | addr_t &address) { |
1931 | RegisterValue reg_value; |
1932 | |
1933 | address = LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
1934 | addr_t cfa_reg_contents; |
1935 | |
1936 | switch (fa.GetValueType()) { |
1937 | case UnwindPlan::Row::FAValue::isRegisterDereferenced: { |
1938 | RegisterNumber cfa_reg(m_thread, row_register_kind, |
1939 | fa.GetRegisterNumber()); |
1940 | if (ReadGPRValue(cfa_reg, cfa_reg_contents)) { |
1941 | const RegisterInfo *reg_info = |
1942 | GetRegisterInfoAtIndex(cfa_reg.GetAsKind(eRegisterKindLLDB)); |
1943 | RegisterValue reg_value; |
1944 | if (reg_info) { |
1945 | Status error = ReadRegisterValueFromMemory( |
1946 | reg_info, cfa_reg_contents, reg_info->byte_size, reg_value); |
1947 | if (error.Success()) { |
1948 | address = reg_value.GetAsUInt64(); |
1949 | if (ABISP abi_sp = m_thread.GetProcess()->GetABI()) |
1950 | address = abi_sp->FixCodeAddress(address); |
1951 | UnwindLogMsg( |
1952 | "CFA value via dereferencing reg %s (%d): reg has val 0x%" PRIx64"llx" |
1953 | ", CFA value is 0x%" PRIx64"llx", |
1954 | cfa_reg.GetName(), cfa_reg.GetAsKind(eRegisterKindLLDB), |
1955 | cfa_reg_contents, address); |
1956 | return true; |
1957 | } else { |
1958 | UnwindLogMsg("Tried to deref reg %s (%d) [0x%" PRIx64"llx" |
1959 | "] but memory read failed.", |
1960 | cfa_reg.GetName(), cfa_reg.GetAsKind(eRegisterKindLLDB), |
1961 | cfa_reg_contents); |
1962 | } |
1963 | } |
1964 | } |
1965 | break; |
1966 | } |
1967 | case UnwindPlan::Row::FAValue::isRegisterPlusOffset: { |
1968 | RegisterNumber cfa_reg(m_thread, row_register_kind, |
1969 | fa.GetRegisterNumber()); |
1970 | if (ReadGPRValue(cfa_reg, cfa_reg_contents)) { |
1971 | if (cfa_reg_contents == LLDB_INVALID_ADDRESS0xffffffffffffffffULL || cfa_reg_contents == 0 || |
1972 | cfa_reg_contents == 1) { |
1973 | UnwindLogMsg( |
1974 | "Got an invalid CFA register value - reg %s (%d), value 0x%" PRIx64"llx", |
1975 | cfa_reg.GetName(), cfa_reg.GetAsKind(eRegisterKindLLDB), |
1976 | cfa_reg_contents); |
1977 | cfa_reg_contents = LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
Value stored to 'cfa_reg_contents' is never read | |
1978 | return false; |
1979 | } |
1980 | address = cfa_reg_contents + fa.GetOffset(); |
1981 | UnwindLogMsg( |
1982 | "CFA is 0x%" PRIx64"llx" ": Register %s (%d) contents are 0x%" PRIx64"llx" |
1983 | ", offset is %d", |
1984 | address, cfa_reg.GetName(), cfa_reg.GetAsKind(eRegisterKindLLDB), |
1985 | cfa_reg_contents, fa.GetOffset()); |
1986 | return true; |
1987 | } |
1988 | break; |
1989 | } |
1990 | case UnwindPlan::Row::FAValue::isDWARFExpression: { |
1991 | ExecutionContext exe_ctx(m_thread.shared_from_this()); |
1992 | Process *process = exe_ctx.GetProcessPtr(); |
1993 | DataExtractor dwarfdata(fa.GetDWARFExpressionBytes(), |
1994 | fa.GetDWARFExpressionLength(), |
1995 | process->GetByteOrder(), |
1996 | process->GetAddressByteSize()); |
1997 | ModuleSP opcode_ctx; |
1998 | DWARFExpression dwarfexpr(opcode_ctx, dwarfdata, nullptr); |
1999 | dwarfexpr.SetRegisterKind(row_register_kind); |
2000 | Value result; |
2001 | Status error; |
2002 | if (dwarfexpr.Evaluate(&exe_ctx, this, 0, nullptr, nullptr, result, |
2003 | &error)) { |
2004 | address = result.GetScalar().ULongLong(); |
2005 | if (ABISP abi_sp = m_thread.GetProcess()->GetABI()) |
2006 | address = abi_sp->FixCodeAddress(address); |
2007 | |
2008 | UnwindLogMsg("CFA value set by DWARF expression is 0x%" PRIx64"llx", |
2009 | address); |
2010 | return true; |
2011 | } |
2012 | UnwindLogMsg("Failed to set CFA value via DWARF expression: %s", |
2013 | error.AsCString()); |
2014 | break; |
2015 | } |
2016 | case UnwindPlan::Row::FAValue::isRaSearch: { |
2017 | Process &process = *m_thread.GetProcess(); |
2018 | lldb::addr_t return_address_hint = GetReturnAddressHint(fa.GetOffset()); |
2019 | if (return_address_hint == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) |
2020 | return false; |
2021 | const unsigned max_iterations = 256; |
2022 | for (unsigned i = 0; i < max_iterations; ++i) { |
2023 | Status st; |
2024 | lldb::addr_t candidate_addr = |
2025 | return_address_hint + i * process.GetAddressByteSize(); |
2026 | lldb::addr_t candidate = |
2027 | process.ReadPointerFromMemory(candidate_addr, st); |
2028 | if (st.Fail()) { |
2029 | UnwindLogMsg("Cannot read memory at 0x%" PRIx64"llx" ": %s", candidate_addr, |
2030 | st.AsCString()); |
2031 | return false; |
2032 | } |
2033 | Address addr; |
2034 | uint32_t permissions; |
2035 | if (process.GetLoadAddressPermissions(candidate, permissions) && |
2036 | permissions & lldb::ePermissionsExecutable) { |
2037 | address = candidate_addr; |
2038 | UnwindLogMsg("Heuristically found CFA: 0x%" PRIx64"llx", address); |
2039 | return true; |
2040 | } |
2041 | } |
2042 | UnwindLogMsg("No suitable CFA found"); |
2043 | break; |
2044 | } |
2045 | default: |
2046 | return false; |
2047 | } |
2048 | return false; |
2049 | } |
2050 | |
2051 | lldb::addr_t RegisterContextUnwind::GetReturnAddressHint(int32_t plan_offset) { |
2052 | addr_t hint; |
2053 | if (!ReadGPRValue(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP1, hint)) |
2054 | return LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
2055 | if (!m_sym_ctx.module_sp || !m_sym_ctx.symbol) |
2056 | return LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
2057 | |
2058 | hint += plan_offset; |
2059 | |
2060 | if (auto next = GetNextFrame()) { |
2061 | if (!next->m_sym_ctx.module_sp || !next->m_sym_ctx.symbol) |
2062 | return LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
2063 | if (auto expected_size = |
2064 | next->m_sym_ctx.module_sp->GetSymbolFile()->GetParameterStackSize( |
2065 | *next->m_sym_ctx.symbol)) |
2066 | hint += *expected_size; |
2067 | else { |
2068 | UnwindLogMsgVerbose("Could not retrieve parameter size: %s", |
2069 | llvm::toString(expected_size.takeError()).c_str()); |
2070 | return LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
2071 | } |
2072 | } |
2073 | return hint; |
2074 | } |
2075 | |
2076 | // Retrieve a general purpose register value for THIS frame, as saved by the |
2077 | // NEXT frame, i.e. the frame that |
2078 | // this frame called. e.g. |
2079 | // |
2080 | // foo () { } |
2081 | // bar () { foo (); } |
2082 | // main () { bar (); } |
2083 | // |
2084 | // stopped in foo() so |
2085 | // frame 0 - foo |
2086 | // frame 1 - bar |
2087 | // frame 2 - main |
2088 | // and this RegisterContext is for frame 1 (bar) - if we want to get the pc |
2089 | // value for frame 1, we need to ask |
2090 | // where frame 0 (the "next" frame) saved that and retrieve the value. |
2091 | |
2092 | bool RegisterContextUnwind::ReadGPRValue(lldb::RegisterKind register_kind, |
2093 | uint32_t regnum, addr_t &value) { |
2094 | if (!IsValid()) |
2095 | return false; |
2096 | |
2097 | uint32_t lldb_regnum; |
2098 | if (register_kind == eRegisterKindLLDB) { |
2099 | lldb_regnum = regnum; |
2100 | } else if (!m_thread.GetRegisterContext()->ConvertBetweenRegisterKinds( |
2101 | register_kind, regnum, eRegisterKindLLDB, lldb_regnum)) { |
2102 | return false; |
2103 | } |
2104 | |
2105 | const RegisterInfo *reg_info = GetRegisterInfoAtIndex(lldb_regnum); |
2106 | RegisterValue reg_value; |
2107 | // if this is frame 0 (currently executing frame), get the requested reg |
2108 | // contents from the actual thread registers |
2109 | if (IsFrameZero()) { |
2110 | if (m_thread.GetRegisterContext()->ReadRegister(reg_info, reg_value)) { |
2111 | value = reg_value.GetAsUInt64(); |
2112 | return true; |
2113 | } |
2114 | return false; |
2115 | } |
2116 | |
2117 | bool pc_register = false; |
2118 | uint32_t generic_regnum; |
2119 | if (register_kind == eRegisterKindGeneric && |
2120 | (regnum == LLDB_REGNUM_GENERIC_PC0 || regnum == LLDB_REGNUM_GENERIC_RA3)) { |
2121 | pc_register = true; |
2122 | } else if (m_thread.GetRegisterContext()->ConvertBetweenRegisterKinds( |
2123 | register_kind, regnum, eRegisterKindGeneric, generic_regnum) && |
2124 | (generic_regnum == LLDB_REGNUM_GENERIC_PC0 || |
2125 | generic_regnum == LLDB_REGNUM_GENERIC_RA3)) { |
2126 | pc_register = true; |
2127 | } |
2128 | |
2129 | lldb_private::UnwindLLDB::RegisterLocation regloc; |
2130 | if (!m_parent_unwind.SearchForSavedLocationForRegister( |
2131 | lldb_regnum, regloc, m_frame_number - 1, pc_register)) { |
2132 | return false; |
2133 | } |
2134 | if (ReadRegisterValueFromRegisterLocation(regloc, reg_info, reg_value)) { |
2135 | value = reg_value.GetAsUInt64(); |
2136 | if (pc_register) { |
2137 | if (ProcessSP process_sp = m_thread.GetProcess()) { |
2138 | if (ABISP abi = process_sp->GetABI()) |
2139 | value = abi->FixCodeAddress(value); |
2140 | } |
2141 | } |
2142 | return true; |
2143 | } |
2144 | return false; |
2145 | } |
2146 | |
2147 | bool RegisterContextUnwind::ReadGPRValue(const RegisterNumber ®num, |
2148 | addr_t &value) { |
2149 | return ReadGPRValue(regnum.GetRegisterKind(), regnum.GetRegisterNumber(), |
2150 | value); |
2151 | } |
2152 | |
2153 | // Find the value of a register in THIS frame |
2154 | |
2155 | bool RegisterContextUnwind::ReadRegister(const RegisterInfo *reg_info, |
2156 | RegisterValue &value) { |
2157 | if (!IsValid()) |
2158 | return false; |
2159 | |
2160 | const uint32_t lldb_regnum = reg_info->kinds[eRegisterKindLLDB]; |
2161 | UnwindLogMsgVerbose("looking for register saved location for reg %d", |
2162 | lldb_regnum); |
2163 | |
2164 | // If this is the 0th frame, hand this over to the live register context |
2165 | if (IsFrameZero()) { |
2166 | UnwindLogMsgVerbose("passing along to the live register context for reg %d", |
2167 | lldb_regnum); |
2168 | return m_thread.GetRegisterContext()->ReadRegister(reg_info, value); |
2169 | } |
2170 | |
2171 | bool is_pc_regnum = false; |
2172 | if (reg_info->kinds[eRegisterKindGeneric] == LLDB_REGNUM_GENERIC_PC0 || |
2173 | reg_info->kinds[eRegisterKindGeneric] == LLDB_REGNUM_GENERIC_RA3) { |
2174 | is_pc_regnum = true; |
2175 | } |
2176 | |
2177 | lldb_private::UnwindLLDB::RegisterLocation regloc; |
2178 | // Find out where the NEXT frame saved THIS frame's register contents |
2179 | if (!m_parent_unwind.SearchForSavedLocationForRegister( |
2180 | lldb_regnum, regloc, m_frame_number - 1, is_pc_regnum)) |
2181 | return false; |
2182 | |
2183 | bool result = ReadRegisterValueFromRegisterLocation(regloc, reg_info, value); |
2184 | if (result) { |
2185 | if (is_pc_regnum && value.GetType() == RegisterValue::eTypeUInt64) { |
2186 | addr_t reg_value = value.GetAsUInt64(LLDB_INVALID_ADDRESS0xffffffffffffffffULL); |
2187 | if (reg_value != LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
2188 | if(ProcessSP process_sp = m_thread.GetProcess()) { |
2189 | if (ABISP abi = process_sp->GetABI()) |
2190 | value = abi->FixCodeAddress(reg_value); |
2191 | } |
2192 | } |
2193 | } |
2194 | } |
2195 | return result; |
2196 | } |
2197 | |
2198 | bool RegisterContextUnwind::WriteRegister(const RegisterInfo *reg_info, |
2199 | const RegisterValue &value) { |
2200 | if (!IsValid()) |
2201 | return false; |
2202 | |
2203 | const uint32_t lldb_regnum = reg_info->kinds[eRegisterKindLLDB]; |
2204 | UnwindLogMsgVerbose("looking for register saved location for reg %d", |
2205 | lldb_regnum); |
2206 | |
2207 | // If this is the 0th frame, hand this over to the live register context |
2208 | if (IsFrameZero()) { |
2209 | UnwindLogMsgVerbose("passing along to the live register context for reg %d", |
2210 | lldb_regnum); |
2211 | return m_thread.GetRegisterContext()->WriteRegister(reg_info, value); |
2212 | } |
2213 | |
2214 | lldb_private::UnwindLLDB::RegisterLocation regloc; |
2215 | // Find out where the NEXT frame saved THIS frame's register contents |
2216 | if (!m_parent_unwind.SearchForSavedLocationForRegister( |
2217 | lldb_regnum, regloc, m_frame_number - 1, false)) |
2218 | return false; |
2219 | |
2220 | return WriteRegisterValueToRegisterLocation(regloc, reg_info, value); |
2221 | } |
2222 | |
2223 | // Don't need to implement this one |
2224 | bool RegisterContextUnwind::ReadAllRegisterValues(lldb::DataBufferSP &data_sp) { |
2225 | return false; |
2226 | } |
2227 | |
2228 | // Don't need to implement this one |
2229 | bool RegisterContextUnwind::WriteAllRegisterValues( |
2230 | const lldb::DataBufferSP &data_sp) { |
2231 | return false; |
2232 | } |
2233 | |
2234 | // Retrieve the pc value for THIS from |
2235 | |
2236 | bool RegisterContextUnwind::GetCFA(addr_t &cfa) { |
2237 | if (!IsValid()) { |
2238 | return false; |
2239 | } |
2240 | if (m_cfa == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
2241 | return false; |
2242 | } |
2243 | cfa = m_cfa; |
2244 | return true; |
2245 | } |
2246 | |
2247 | RegisterContextUnwind::SharedPtr RegisterContextUnwind::GetNextFrame() const { |
2248 | RegisterContextUnwind::SharedPtr regctx; |
2249 | if (m_frame_number == 0) |
2250 | return regctx; |
2251 | return m_parent_unwind.GetRegisterContextForFrameNum(m_frame_number - 1); |
2252 | } |
2253 | |
2254 | RegisterContextUnwind::SharedPtr RegisterContextUnwind::GetPrevFrame() const { |
2255 | RegisterContextUnwind::SharedPtr regctx; |
2256 | return m_parent_unwind.GetRegisterContextForFrameNum(m_frame_number + 1); |
2257 | } |
2258 | |
2259 | // Retrieve the address of the start of the function of THIS frame |
2260 | |
2261 | bool RegisterContextUnwind::GetStartPC(addr_t &start_pc) { |
2262 | if (!IsValid()) |
2263 | return false; |
2264 | |
2265 | if (!m_start_pc.IsValid()) { |
2266 | bool read_successfully = ReadPC (start_pc); |
2267 | if (read_successfully) |
2268 | { |
2269 | ProcessSP process_sp (m_thread.GetProcess()); |
2270 | if (process_sp) |
2271 | { |
2272 | ABI *abi = process_sp->GetABI().get(); |
2273 | if (abi) |
2274 | start_pc = abi->FixCodeAddress(start_pc); |
2275 | } |
2276 | } |
2277 | return read_successfully; |
2278 | } |
2279 | start_pc = m_start_pc.GetLoadAddress(CalculateTarget().get()); |
2280 | return true; |
2281 | } |
2282 | |
2283 | // Retrieve the current pc value for THIS frame, as saved by the NEXT frame. |
2284 | |
2285 | bool RegisterContextUnwind::ReadPC(addr_t &pc) { |
2286 | if (!IsValid()) |
2287 | return false; |
2288 | |
2289 | bool above_trap_handler = false; |
2290 | if (GetNextFrame().get() && GetNextFrame()->IsValid() && |
2291 | GetNextFrame()->IsTrapHandlerFrame()) |
2292 | above_trap_handler = true; |
2293 | |
2294 | if (ReadGPRValue(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC0, pc)) { |
2295 | // A pc value of 0 or 1 is impossible in the middle of the stack -- it |
2296 | // indicates the end of a stack walk. |
2297 | // On the currently executing frame (or such a frame interrupted |
2298 | // asynchronously by sigtramp et al) this may occur if code has jumped |
2299 | // through a NULL pointer -- we want to be able to unwind past that frame |
2300 | // to help find the bug. |
2301 | |
2302 | ProcessSP process_sp (m_thread.GetProcess()); |
2303 | if (process_sp) |
2304 | { |
2305 | ABI *abi = process_sp->GetABI().get(); |
2306 | if (abi) |
2307 | pc = abi->FixCodeAddress(pc); |
2308 | } |
2309 | |
2310 | return !(m_all_registers_available == false && |
2311 | above_trap_handler == false && (pc == 0 || pc == 1)); |
2312 | } else { |
2313 | return false; |
2314 | } |
2315 | } |
2316 | |
2317 | void RegisterContextUnwind::UnwindLogMsg(const char *fmt, ...) { |
2318 | Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND(1u << 15))); |
2319 | if (log) { |
2320 | va_list args; |
2321 | va_start(args, fmt)__builtin_va_start(args, fmt); |
2322 | |
2323 | char *logmsg; |
2324 | if (vasprintf(&logmsg, fmt, args) == -1 || logmsg == nullptr) { |
2325 | if (logmsg) |
2326 | free(logmsg); |
2327 | va_end(args)__builtin_va_end(args); |
2328 | return; |
2329 | } |
2330 | va_end(args)__builtin_va_end(args); |
2331 | |
2332 | LLDB_LOGF(log, "%*sth%d/fr%u %s",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("%*sth%d/fr%u %s", m_frame_number < 100 ? m_frame_number : 100, "", m_thread.GetIndexID(), m_frame_number , logmsg); } while (0) |
2333 | m_frame_number < 100 ? m_frame_number : 100, "",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("%*sth%d/fr%u %s", m_frame_number < 100 ? m_frame_number : 100, "", m_thread.GetIndexID(), m_frame_number , logmsg); } while (0) |
2334 | m_thread.GetIndexID(), m_frame_number, logmsg)do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("%*sth%d/fr%u %s", m_frame_number < 100 ? m_frame_number : 100, "", m_thread.GetIndexID(), m_frame_number , logmsg); } while (0); |
2335 | free(logmsg); |
2336 | } |
2337 | } |
2338 | |
2339 | void RegisterContextUnwind::UnwindLogMsgVerbose(const char *fmt, ...) { |
2340 | Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND(1u << 15))); |
2341 | if (log && log->GetVerbose()) { |
2342 | va_list args; |
2343 | va_start(args, fmt)__builtin_va_start(args, fmt); |
2344 | |
2345 | char *logmsg; |
2346 | if (vasprintf(&logmsg, fmt, args) == -1 || logmsg == nullptr) { |
2347 | if (logmsg) |
2348 | free(logmsg); |
2349 | va_end(args)__builtin_va_end(args); |
2350 | return; |
2351 | } |
2352 | va_end(args)__builtin_va_end(args); |
2353 | |
2354 | LLDB_LOGF(log, "%*sth%d/fr%u %s",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("%*sth%d/fr%u %s", m_frame_number < 100 ? m_frame_number : 100, "", m_thread.GetIndexID(), m_frame_number , logmsg); } while (0) |
2355 | m_frame_number < 100 ? m_frame_number : 100, "",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("%*sth%d/fr%u %s", m_frame_number < 100 ? m_frame_number : 100, "", m_thread.GetIndexID(), m_frame_number , logmsg); } while (0) |
2356 | m_thread.GetIndexID(), m_frame_number, logmsg)do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("%*sth%d/fr%u %s", m_frame_number < 100 ? m_frame_number : 100, "", m_thread.GetIndexID(), m_frame_number , logmsg); } while (0); |
2357 | free(logmsg); |
2358 | } |
2359 | } |