OLD | NEW |
1 // Copyright (c) 2013 Google Inc. | 1 // Copyright (c) 2013 Google Inc. |
2 // All rights reserved. | 2 // All rights reserved. |
3 // | 3 // |
4 // Redistribution and use in source and binary forms, with or without | 4 // Redistribution and use in source and binary forms, with or without |
5 // modification, are permitted provided that the following conditions are | 5 // modification, are permitted provided that the following conditions are |
6 // met: | 6 // met: |
7 // | 7 // |
8 // * Redistributions of source code must retain the above copyright | 8 // * Redistributions of source code must retain the above copyright |
9 // notice, this list of conditions and the following disclaimer. | 9 // notice, this list of conditions and the following disclaimer. |
10 // * Redistributions in binary form must reproduce the above | 10 // * Redistributions in binary form must reproduce the above |
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46 #include "processor/windows_frame_info.h" | 46 #include "processor/windows_frame_info.h" |
47 #include "google_breakpad/common/minidump_cpu_mips.h" | 47 #include "google_breakpad/common/minidump_cpu_mips.h" |
48 | 48 |
49 namespace google_breakpad { | 49 namespace google_breakpad { |
50 | 50 |
51 StackwalkerMIPS::StackwalkerMIPS(const SystemInfo* system_info, | 51 StackwalkerMIPS::StackwalkerMIPS(const SystemInfo* system_info, |
52 const MDRawContextMIPS* context, | 52 const MDRawContextMIPS* context, |
53 MemoryRegion* memory, | 53 MemoryRegion* memory, |
54 const CodeModules* modules, | 54 const CodeModules* modules, |
55 StackFrameSymbolizer* resolver_helper) | 55 StackFrameSymbolizer* resolver_helper) |
56 : Stackwalker(system_info, memory, modules, resolver_helper), | 56 : Stackwalker(system_info, memory, modules, resolver_helper), |
57 context_(context) { | 57 context_(context) { |
58 if (memory_ && memory_->GetBase() + memory_->GetSize() - 1 > 0xffffffff) { | 58 if (context_->context_flags & MD_CONTEXT_MIPS64 ) { |
59 BPLOG(ERROR) << "Memory out of range for stackwalking: " | 59 if ((memory_ && memory_->GetBase() + memory_->GetSize() - 1) |
60 << HexString(memory_->GetBase()) | 60 > 0xffffffffffffffff) { |
61 << "+" | 61 BPLOG(ERROR) << "Memory out of range for stackwalking mips64: " |
62 << HexString(memory_->GetSize()); | 62 << HexString(memory_->GetBase()) |
63 memory_ = NULL; | 63 << "+" |
| 64 << HexString(memory_->GetSize()); |
| 65 memory_ = NULL; |
| 66 } |
| 67 } else { |
| 68 if ((memory_ && memory_->GetBase() + memory_->GetSize() - 1) > 0xffffffff) { |
| 69 BPLOG(ERROR) << "Memory out of range for stackwalking mips32: " |
| 70 << HexString(memory_->GetBase()) |
| 71 << "+" |
| 72 << HexString(memory_->GetSize()); |
| 73 memory_ = NULL; |
| 74 } |
64 } | 75 } |
65 } | 76 } |
66 | 77 |
67 StackFrame* StackwalkerMIPS::GetContextFrame() { | 78 StackFrame* StackwalkerMIPS::GetContextFrame() { |
68 if (!context_) { | 79 if (!context_) { |
69 BPLOG(ERROR) << "Can't get context frame without context."; | 80 BPLOG(ERROR) << "Can't get context frame without context."; |
70 return NULL; | 81 return NULL; |
71 } | 82 } |
72 | 83 |
73 StackFrameMIPS* frame = new StackFrameMIPS(); | 84 StackFrameMIPS* frame = new StackFrameMIPS(); |
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89 "$s4", "$s5", "$s6", "$s7", "$t8", "$t9", "$k0", "$k1", "$gp", "$sp", | 100 "$s4", "$s5", "$s6", "$s7", "$t8", "$t9", "$k0", "$k1", "$gp", "$sp", |
90 "$fp", "$ra", NULL | 101 "$fp", "$ra", NULL |
91 // TODO(gordanac): add float point save registers | 102 // TODO(gordanac): add float point save registers |
92 }; | 103 }; |
93 | 104 |
94 StackFrameMIPS* StackwalkerMIPS::GetCallerByCFIFrameInfo( | 105 StackFrameMIPS* StackwalkerMIPS::GetCallerByCFIFrameInfo( |
95 const vector<StackFrame*>& frames, | 106 const vector<StackFrame*>& frames, |
96 CFIFrameInfo* cfi_frame_info) { | 107 CFIFrameInfo* cfi_frame_info) { |
97 StackFrameMIPS* last_frame = static_cast<StackFrameMIPS*>(frames.back()); | 108 StackFrameMIPS* last_frame = static_cast<StackFrameMIPS*>(frames.back()); |
98 | 109 |
99 uint32_t sp = 0, pc = 0; | 110 if (context_->context_flags & MD_CONTEXT_MIPS) { |
| 111 uint32_t sp = 0, pc = 0; |
100 | 112 |
101 // Populate a dictionary with the valid register values in last_frame. | 113 // Populate a dictionary with the valid register values in last_frame. |
102 CFIFrameInfo::RegisterValueMap<uint32_t> callee_registers; | 114 CFIFrameInfo::RegisterValueMap<uint32_t> callee_registers; |
103 // Use the STACK CFI data to recover the caller's register values. | 115 // Use the STACK CFI data to recover the caller's register values. |
104 CFIFrameInfo::RegisterValueMap<uint32_t> caller_registers; | 116 CFIFrameInfo::RegisterValueMap<uint32_t> caller_registers; |
105 | 117 |
106 for (int i = 0; kRegisterNames[i]; ++i) { | 118 for (int i = 0; kRegisterNames[i]; ++i) { |
107 caller_registers[kRegisterNames[i]] = last_frame->context.iregs[i]; | 119 caller_registers[kRegisterNames[i]] = last_frame->context.iregs[i]; |
108 callee_registers[kRegisterNames[i]] = last_frame->context.iregs[i]; | 120 callee_registers[kRegisterNames[i]] = last_frame->context.iregs[i]; |
| 121 } |
| 122 |
| 123 if (!cfi_frame_info->FindCallerRegs(callee_registers, *memory_, |
| 124 &caller_registers)) { |
| 125 return NULL; |
| 126 } |
| 127 |
| 128 CFIFrameInfo::RegisterValueMap<uint32_t>::const_iterator entry = |
| 129 caller_registers.find(".cfa"); |
| 130 |
| 131 if (entry != caller_registers.end()) { |
| 132 sp = entry->second; |
| 133 caller_registers["$sp"] = entry->second; |
| 134 } |
| 135 |
| 136 entry = caller_registers.find(".ra"); |
| 137 if (entry != caller_registers.end()) { |
| 138 caller_registers["$ra"] = entry->second; |
| 139 pc = entry->second - 2 * sizeof(pc); |
| 140 } |
| 141 caller_registers["$pc"] = pc; |
| 142 // Construct a new stack frame given the values the CFI recovered. |
| 143 scoped_ptr<StackFrameMIPS> frame(new StackFrameMIPS()); |
| 144 |
| 145 for (int i = 0; kRegisterNames[i]; ++i) { |
| 146 CFIFrameInfo::RegisterValueMap<uint32_t>::const_iterator caller_entry = |
| 147 caller_registers.find(kRegisterNames[i]); |
| 148 |
| 149 if (caller_entry != caller_registers.end()) { |
| 150 // The value of this register is recovered; fill the context with the |
| 151 // value from caller_registers. |
| 152 frame->context.iregs[i] = caller_entry->second; |
| 153 frame->context_validity |= StackFrameMIPS::RegisterValidFlag(i); |
| 154 } else if (((i >= INDEX_MIPS_REG_S0 && i <= INDEX_MIPS_REG_S7) || |
| 155 (i > INDEX_MIPS_REG_GP && i < INDEX_MIPS_REG_RA)) && |
| 156 (last_frame->context_validity & |
| 157 StackFrameMIPS::RegisterValidFlag(i))) { |
| 158 // If the STACK CFI data doesn't mention some callee-save register, and |
| 159 // it is valid in the callee, assume the callee has not yet changed it. |
| 160 // Calee-save registers according to the MIPS o32 ABI specification are: |
| 161 // $s0 to $s7 |
| 162 // $sp, $s8 |
| 163 frame->context.iregs[i] = last_frame->context.iregs[i]; |
| 164 frame->context_validity |= StackFrameMIPS::RegisterValidFlag(i); |
| 165 } |
| 166 } |
| 167 |
| 168 frame->context.epc = caller_registers["$pc"]; |
| 169 frame->instruction = caller_registers["$pc"]; |
| 170 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_PC; |
| 171 |
| 172 frame->context.iregs[MD_CONTEXT_MIPS_REG_RA] = caller_registers["$ra"]; |
| 173 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_RA; |
| 174 |
| 175 frame->trust = StackFrame::FRAME_TRUST_CFI; |
| 176 |
| 177 return frame.release(); |
| 178 } else { |
| 179 uint64_t sp = 0, pc = 0; |
| 180 |
| 181 // Populate a dictionary with the valid register values in last_frame. |
| 182 CFIFrameInfo::RegisterValueMap<uint64_t> callee_registers; |
| 183 // Use the STACK CFI data to recover the caller's register values. |
| 184 CFIFrameInfo::RegisterValueMap<uint64_t> caller_registers; |
| 185 |
| 186 for (int i = 0; kRegisterNames[i]; ++i) { |
| 187 caller_registers[kRegisterNames[i]] = last_frame->context.iregs[i]; |
| 188 callee_registers[kRegisterNames[i]] = last_frame->context.iregs[i]; |
| 189 } |
| 190 |
| 191 if (!cfi_frame_info->FindCallerRegs(callee_registers, *memory_, |
| 192 &caller_registers)) { |
| 193 return NULL; |
| 194 } |
| 195 |
| 196 CFIFrameInfo::RegisterValueMap<uint64_t>::const_iterator entry = |
| 197 caller_registers.find(".cfa"); |
| 198 |
| 199 if (entry != caller_registers.end()) { |
| 200 sp = entry->second; |
| 201 caller_registers["$sp"] = entry->second; |
| 202 } |
| 203 |
| 204 entry = caller_registers.find(".ra"); |
| 205 if (entry != caller_registers.end()) { |
| 206 caller_registers["$ra"] = entry->second; |
| 207 pc = entry->second - 2 * sizeof(pc); |
| 208 } |
| 209 caller_registers["$pc"] = pc; |
| 210 // Construct a new stack frame given the values the CFI recovered. |
| 211 scoped_ptr<StackFrameMIPS> frame(new StackFrameMIPS()); |
| 212 |
| 213 for (int i = 0; kRegisterNames[i]; ++i) { |
| 214 CFIFrameInfo::RegisterValueMap<uint64_t>::const_iterator caller_entry = |
| 215 caller_registers.find(kRegisterNames[i]); |
| 216 |
| 217 if (caller_entry != caller_registers.end()) { |
| 218 // The value of this register is recovered; fill the context with the |
| 219 // value from caller_registers. |
| 220 frame->context.iregs[i] = caller_entry->second; |
| 221 frame->context_validity |= StackFrameMIPS::RegisterValidFlag(i); |
| 222 } else if (((i >= INDEX_MIPS_REG_S0 && i <= INDEX_MIPS_REG_S7) || |
| 223 (i >= INDEX_MIPS_REG_GP && i < INDEX_MIPS_REG_RA)) && |
| 224 (last_frame->context_validity & |
| 225 StackFrameMIPS::RegisterValidFlag(i))) { |
| 226 // If the STACK CFI data doesn't mention some callee-save register, and |
| 227 // it is valid in the callee, assume the callee has not yet changed it. |
| 228 // Calee-save registers according to the MIPS o32 ABI specification are: |
| 229 // $s0 to $s7 |
| 230 // $sp, $s8 |
| 231 frame->context.iregs[i] = last_frame->context.iregs[i]; |
| 232 frame->context_validity |= StackFrameMIPS::RegisterValidFlag(i); |
| 233 } |
| 234 } |
| 235 |
| 236 frame->context.epc = caller_registers["$pc"]; |
| 237 frame->instruction = caller_registers["$pc"]; |
| 238 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_PC; |
| 239 |
| 240 frame->context.iregs[MD_CONTEXT_MIPS_REG_RA] = caller_registers["$ra"]; |
| 241 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_RA; |
| 242 |
| 243 frame->trust = StackFrame::FRAME_TRUST_CFI; |
| 244 |
| 245 return frame.release(); |
109 } | 246 } |
110 | |
111 if (!cfi_frame_info->FindCallerRegs(callee_registers, *memory_, | |
112 &caller_registers)) { | |
113 return NULL; | |
114 } | |
115 | |
116 CFIFrameInfo::RegisterValueMap<uint32_t>::const_iterator entry = | |
117 caller_registers.find(".cfa"); | |
118 | |
119 if (entry != caller_registers.end()) { | |
120 sp = entry->second; | |
121 caller_registers["$sp"] = entry->second; | |
122 } | |
123 | |
124 entry = caller_registers.find(".ra"); | |
125 if (entry != caller_registers.end()) { | |
126 caller_registers["$ra"] = entry->second; | |
127 pc = entry->second - 2 * sizeof(pc); | |
128 } | |
129 caller_registers["$pc"] = pc; | |
130 // Construct a new stack frame given the values the CFI recovered. | |
131 scoped_ptr<StackFrameMIPS> frame(new StackFrameMIPS()); | |
132 | |
133 for (int i = 0; kRegisterNames[i]; ++i) { | |
134 CFIFrameInfo::RegisterValueMap<uint32_t>::const_iterator caller_entry = | |
135 caller_registers.find(kRegisterNames[i]); | |
136 | |
137 if (caller_entry != caller_registers.end()) { | |
138 // The value of this register is recovered; fill the context with the | |
139 // value from caller_registers. | |
140 frame->context.iregs[i] = caller_entry->second; | |
141 frame->context_validity |= StackFrameMIPS::RegisterValidFlag(i); | |
142 } else if (((i >= INDEX_MIPS_REG_S0 && i <= INDEX_MIPS_REG_S7) || | |
143 (i > INDEX_MIPS_REG_GP && i < INDEX_MIPS_REG_RA)) && | |
144 (last_frame->context_validity & | |
145 StackFrameMIPS::RegisterValidFlag(i))) { | |
146 // If the STACK CFI data doesn't mention some callee-save register, and | |
147 // it is valid in the callee, assume the callee has not yet changed it. | |
148 // Calee-save registers according to the MIPS o32 ABI specification are: | |
149 // $s0 to $s7 | |
150 // $sp, $s8 | |
151 frame->context.iregs[i] = last_frame->context.iregs[i]; | |
152 frame->context_validity |= StackFrameMIPS::RegisterValidFlag(i); | |
153 } | |
154 } | |
155 | |
156 frame->context.epc = caller_registers["$pc"]; | |
157 frame->instruction = caller_registers["$pc"]; | |
158 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_PC; | |
159 | |
160 frame->context.iregs[MD_CONTEXT_MIPS_REG_RA] = caller_registers["$ra"]; | |
161 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_RA; | |
162 | |
163 frame->trust = StackFrame::FRAME_TRUST_CFI; | |
164 | |
165 return frame.release(); | |
166 } | 247 } |
167 | 248 |
168 StackFrame* StackwalkerMIPS::GetCallerFrame(const CallStack* stack, | 249 StackFrame* StackwalkerMIPS::GetCallerFrame(const CallStack* stack, |
169 bool stack_scan_allowed) { | 250 bool stack_scan_allowed) { |
170 if (!memory_ || !stack) { | 251 if (!memory_ || !stack) { |
171 BPLOG(ERROR) << "Can't get caller frame without memory or stack"; | 252 BPLOG(ERROR) << "Can't get caller frame without memory or stack"; |
172 return NULL; | 253 return NULL; |
173 } | 254 } |
174 | 255 |
175 const vector<StackFrame*>& frames = *stack->frames(); | 256 const vector<StackFrame*>& frames = *stack->frames(); |
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197 return NULL; | 278 return NULL; |
198 } | 279 } |
199 | 280 |
200 // If the new stack pointer is at a lower address than the old, then | 281 // If the new stack pointer is at a lower address than the old, then |
201 // that's clearly incorrect. Treat this as end-of-stack to enforce | 282 // that's clearly incorrect. Treat this as end-of-stack to enforce |
202 // progress and avoid infinite loops. | 283 // progress and avoid infinite loops. |
203 if (new_frame->context.iregs[MD_CONTEXT_MIPS_REG_SP] <= | 284 if (new_frame->context.iregs[MD_CONTEXT_MIPS_REG_SP] <= |
204 last_frame->context.iregs[MD_CONTEXT_MIPS_REG_SP]) { | 285 last_frame->context.iregs[MD_CONTEXT_MIPS_REG_SP]) { |
205 return NULL; | 286 return NULL; |
206 } | 287 } |
207 | 288 |
208 return new_frame.release(); | 289 return new_frame.release(); |
209 } | 290 } |
210 | 291 |
211 StackFrameMIPS* StackwalkerMIPS::GetCallerByStackScan( | 292 StackFrameMIPS* StackwalkerMIPS::GetCallerByStackScan( |
212 const vector<StackFrame*>& frames) { | 293 const vector<StackFrame*>& frames) { |
213 const uint32_t kMaxFrameStackSize = 1024; | 294 const uint32_t kMaxFrameStackSize = 1024; |
214 const uint32_t kMinArgsOnStack = 4; | 295 const uint32_t kMinArgsOnStack = 4; |
215 | 296 |
216 StackFrameMIPS* last_frame = static_cast<StackFrameMIPS*>(frames.back()); | 297 StackFrameMIPS* last_frame = static_cast<StackFrameMIPS*>(frames.back()); |
217 | 298 |
218 uint32_t last_sp = last_frame->context.iregs[MD_CONTEXT_MIPS_REG_SP]; | 299 if (context_->context_flags & MD_CONTEXT_MIPS) { |
219 uint32_t caller_pc, caller_sp, caller_fp; | 300 uint32_t last_sp = last_frame->context.iregs[MD_CONTEXT_MIPS_REG_SP]; |
| 301 uint32_t caller_pc, caller_sp, caller_fp; |
220 | 302 |
221 // Return address cannot be obtained directly. | 303 // Return address cannot be obtained directly. |
222 // Force stackwalking. | 304 // Force stackwalking. |
223 | 305 |
224 // We cannot use frame pointer to get the return address. | 306 // We cannot use frame pointer to get the return address. |
225 // We'll scan the stack for a | 307 // We'll scan the stack for a |
226 // return address. This can happen if last_frame is executing code | 308 // return address. This can happen if last_frame is executing code |
227 // for a module for which we don't have symbols. | 309 // for a module for which we don't have symbols. |
228 int count = kMaxFrameStackSize / sizeof(caller_pc); | 310 int count = kMaxFrameStackSize / sizeof(caller_pc); |
229 | 311 |
230 if (frames.size() > 1) { | 312 if (frames.size() > 1) { |
231 // In case of mips32 ABI stack frame of a nonleaf function | 313 // In case of mips32 ABI stack frame of a nonleaf function |
232 // must have minimum stack frame assigned for 4 arguments (4 words). | 314 // must have minimum stack frame assigned for 4 arguments (4 words). |
233 // Move stack pointer for 4 words to avoid reporting non-existing frames | 315 // Move stack pointer for 4 words to avoid reporting non-existing frames |
234 // for all frames except the topmost one. | 316 // for all frames except the topmost one. |
235 // There is no way of knowing if topmost frame belongs to a leaf or | 317 // There is no way of knowing if topmost frame belongs to a leaf or |
236 // a nonleaf function. | 318 // a nonleaf function. |
237 last_sp += kMinArgsOnStack * sizeof(caller_pc); | 319 last_sp += kMinArgsOnStack * sizeof(caller_pc); |
238 // Adjust 'count' so that return address is scanned only in limits | 320 // Adjust 'count' so that return address is scanned only in limits |
239 // of one stack frame. | 321 // of one stack frame. |
240 count -= kMinArgsOnStack; | 322 count -= kMinArgsOnStack; |
241 } | 323 } |
242 | 324 |
243 do { | 325 do { |
244 // Scanning for return address from stack pointer of the last frame. | 326 // Scanning for return address from stack pointer of the last frame. |
245 if (!ScanForReturnAddress(last_sp, &caller_sp, &caller_pc, count)) { | 327 if (!ScanForReturnAddress(last_sp, &caller_sp, &caller_pc, count)) { |
246 // If we can't find an instruction pointer even with stack scanning, | 328 // If we can't find an instruction pointer even with stack scanning, |
247 // give up. | 329 // give up. |
248 BPLOG(ERROR) << " ScanForReturnAddress failed "; | 330 BPLOG(ERROR) << " ScanForReturnAddress failed "; |
249 return NULL; | 331 return NULL; |
250 } | 332 } |
251 // Get $fp stored in the stack frame. | 333 // Get $fp stored in the stack frame. |
252 if (!memory_->GetMemoryAtAddress(caller_sp - sizeof(caller_pc), | 334 if (!memory_->GetMemoryAtAddress(caller_sp - sizeof(caller_pc), |
253 &caller_fp)) { | 335 &caller_fp)) { |
254 BPLOG(INFO) << " GetMemoryAtAddress for fp failed " ; | 336 BPLOG(INFO) << " GetMemoryAtAddress for fp failed " ; |
| 337 return NULL; |
| 338 } |
| 339 |
| 340 count = count - (caller_sp - last_sp) / sizeof(caller_pc); |
| 341 // Now scan the next address in the stack. |
| 342 last_sp = caller_sp + sizeof(caller_pc); |
| 343 } while ((caller_fp - caller_sp >= kMaxFrameStackSize) && count > 0); |
| 344 |
| 345 if (!count) { |
| 346 BPLOG(INFO) << " No frame found " ; |
255 return NULL; | 347 return NULL; |
256 } | 348 } |
257 | 349 |
258 count = count - (caller_sp - last_sp) / sizeof(caller_pc); | 350 // ScanForReturnAddress found a reasonable return address. Advance |
259 // Now scan the next address in the stack. | 351 // $sp to the location above the one where the return address was |
260 last_sp = caller_sp + sizeof(caller_pc); | 352 // found. |
261 } while ((caller_fp - caller_sp >= kMaxFrameStackSize) && count > 0); | 353 caller_sp += sizeof(caller_pc); |
| 354 // caller_pc is actually containing $ra value; |
| 355 // $pc is two instructions before $ra, |
| 356 // so the caller_pc needs to be decremented accordingly. |
| 357 caller_pc -= 2 * sizeof(caller_pc); |
262 | 358 |
263 if (!count) { | 359 // Create a new stack frame (ownership will be transferred to the caller) |
264 BPLOG(INFO) << " No frame found " ; | 360 // and fill it in. |
265 return NULL; | 361 StackFrameMIPS* frame = new StackFrameMIPS(); |
| 362 frame->trust = StackFrame::FRAME_TRUST_SCAN; |
| 363 frame->context = last_frame->context; |
| 364 frame->context.epc = caller_pc; |
| 365 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_PC; |
| 366 frame->instruction = caller_pc; |
| 367 |
| 368 frame->context.iregs[MD_CONTEXT_MIPS_REG_SP] = caller_sp; |
| 369 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_SP; |
| 370 frame->context.iregs[MD_CONTEXT_MIPS_REG_FP] = caller_fp; |
| 371 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_FP; |
| 372 |
| 373 frame->context.iregs[MD_CONTEXT_MIPS_REG_RA] = |
| 374 caller_pc + 2 * sizeof(caller_pc); |
| 375 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_RA; |
| 376 |
| 377 return frame; |
| 378 } else { |
| 379 uint64_t last_sp = last_frame->context.iregs[MD_CONTEXT_MIPS_REG_SP]; |
| 380 uint64_t caller_pc, caller_sp, caller_fp; |
| 381 |
| 382 // Return address cannot be obtained directly. |
| 383 // Force stackwalking. |
| 384 |
| 385 // We cannot use frame pointer to get the return address. |
| 386 // We'll scan the stack for a |
| 387 // return address. This can happen if last_frame is executing code |
| 388 // for a module for which we don't have symbols. |
| 389 int count = kMaxFrameStackSize / sizeof(caller_pc); |
| 390 |
| 391 do { |
| 392 // Scanning for return address from stack pointer of the last frame. |
| 393 if (!ScanForReturnAddress(last_sp, &caller_sp, &caller_pc, count)) { |
| 394 // If we can't find an instruction pointer even with stack scanning, |
| 395 // give up. |
| 396 BPLOG(ERROR) << " ScanForReturnAddress failed "; |
| 397 return NULL; |
| 398 } |
| 399 // Get $fp stored in the stack frame. |
| 400 if (!memory_->GetMemoryAtAddress(caller_sp - sizeof(caller_pc), |
| 401 &caller_fp)) { |
| 402 BPLOG(INFO) << " GetMemoryAtAddress for fp failed " ; |
| 403 return NULL; |
| 404 } |
| 405 |
| 406 count = count - (caller_sp - last_sp) / sizeof(caller_pc); |
| 407 // Now scan the next address in the stack. |
| 408 last_sp = caller_sp + sizeof(caller_pc); |
| 409 } while ((caller_fp - caller_sp >= kMaxFrameStackSize) && count > 0); |
| 410 |
| 411 if (!count) { |
| 412 BPLOG(INFO) << " No frame found " ; |
| 413 return NULL; |
| 414 } |
| 415 |
| 416 // ScanForReturnAddress found a reasonable return address. Advance |
| 417 // $sp to the location above the one where the return address was |
| 418 // found. |
| 419 caller_sp += sizeof(caller_pc); |
| 420 // caller_pc is actually containing $ra value; |
| 421 // $pc is two instructions before $ra, |
| 422 // so the caller_pc needs to be decremented accordingly. |
| 423 caller_pc -= 2 * sizeof(caller_pc); |
| 424 |
| 425 // Create a new stack frame (ownership will be transferred to the caller) |
| 426 // and fill it in. |
| 427 StackFrameMIPS* frame = new StackFrameMIPS(); |
| 428 frame->trust = StackFrame::FRAME_TRUST_SCAN; |
| 429 frame->context = last_frame->context; |
| 430 frame->context.epc = caller_pc; |
| 431 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_PC; |
| 432 frame->instruction = caller_pc; |
| 433 |
| 434 frame->context.iregs[MD_CONTEXT_MIPS_REG_SP] = caller_sp; |
| 435 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_SP; |
| 436 frame->context.iregs[MD_CONTEXT_MIPS_REG_FP] = caller_fp; |
| 437 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_FP; |
| 438 |
| 439 frame->context.iregs[MD_CONTEXT_MIPS_REG_RA] = |
| 440 caller_pc + 2 * sizeof(caller_pc); |
| 441 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_RA; |
| 442 |
| 443 return frame; |
266 } | 444 } |
267 | |
268 // ScanForReturnAddress found a reasonable return address. Advance | |
269 // $sp to the location above the one where the return address was | |
270 // found. | |
271 caller_sp += sizeof(caller_pc); | |
272 // caller_pc is actually containing $ra value; | |
273 // $pc is two instructions before $ra, | |
274 // so the caller_pc needs to be decremented accordingly. | |
275 caller_pc -= 2 * sizeof(caller_pc); | |
276 | |
277 | |
278 // Create a new stack frame (ownership will be transferred to the caller) | |
279 // and fill it in. | |
280 StackFrameMIPS* frame = new StackFrameMIPS(); | |
281 frame->trust = StackFrame::FRAME_TRUST_SCAN; | |
282 frame->context = last_frame->context; | |
283 frame->context.epc = caller_pc; | |
284 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_PC; | |
285 frame->instruction = caller_pc; | |
286 | |
287 frame->context.iregs[MD_CONTEXT_MIPS_REG_SP] = caller_sp; | |
288 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_SP; | |
289 frame->context.iregs[MD_CONTEXT_MIPS_REG_FP] = caller_fp; | |
290 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_FP; | |
291 | |
292 frame->context.iregs[MD_CONTEXT_MIPS_REG_RA] = | |
293 caller_pc + 2 * sizeof(caller_pc); | |
294 frame->context_validity |= StackFrameMIPS::CONTEXT_VALID_RA; | |
295 | |
296 return frame; | |
297 } | 445 } |
298 | 446 |
299 } // namespace google_breakpad | 447 } // namespace google_breakpad |
300 | 448 |
OLD | NEW |