1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "register_line.h" 18 19 #include "android-base/stringprintf.h" 20 21 #include "dex/dex_instruction-inl.h" 22 #include "method_verifier-inl.h" 23 #include "reg_type-inl.h" 24 #include "register_line-inl.h" 25 26 namespace art { 27 namespace verifier { 28 29 using android::base::StringPrintf; 30 31 bool RegisterLine::CheckConstructorReturn(MethodVerifier* verifier) const { 32 if (kIsDebugBuild && this_initialized_) { 33 // Ensure that there is no UninitializedThisReference type anymore if this_initialized_ is true. 34 for (size_t i = 0; i < num_regs_; i++) { 35 const RegType& type = GetRegisterType(verifier, i); 36 CHECK(!type.IsUninitializedThisReference() && 37 !type.IsUnresolvedAndUninitializedThisReference()) 38 << i << ": " << type.IsUninitializedThisReference() << " in " 39 << verifier->GetMethodReference().PrettyMethod(); 40 } 41 } 42 if (!this_initialized_) { 43 verifier->Fail(VERIFY_ERROR_BAD_CLASS_HARD) 44 << "Constructor returning without calling superclass constructor"; 45 } 46 return this_initialized_; 47 } 48 49 const RegType& RegisterLine::GetInvocationThis(MethodVerifier* verifier, const Instruction* inst, 50 bool allow_failure) { 51 DCHECK(inst->IsInvoke()); 52 const size_t args_count = inst->VRegA(); 53 if (args_count < 1) { 54 if (!allow_failure) { 55 verifier->Fail(VERIFY_ERROR_BAD_CLASS_HARD) << "invoke lacks 'this'"; 56 } 57 return verifier->GetRegTypeCache()->Conflict(); 58 } 59 /* Get the element type of the array held in vsrc */ 60 const uint32_t this_reg = inst->VRegC(); 61 const RegType& this_type = GetRegisterType(verifier, this_reg); 62 if (!this_type.IsReferenceTypes()) { 63 if (!allow_failure) { 64 verifier->Fail(VERIFY_ERROR_BAD_CLASS_HARD) 65 << "tried to get class from non-reference register v" << this_reg 66 << " (type=" << this_type << ")"; 67 } 68 return verifier->GetRegTypeCache()->Conflict(); 69 } 70 return this_type; 71 } 72 73 bool RegisterLine::VerifyRegisterTypeWide(MethodVerifier* verifier, uint32_t vsrc, 74 const RegType& check_type1, 75 const RegType& check_type2) { 76 DCHECK(check_type1.CheckWidePair(check_type2)); 77 // Verify the src register type against the check type refining the type of the register 78 const RegType& src_type = GetRegisterType(verifier, vsrc); 79 if (!check_type1.IsAssignableFrom(src_type, verifier)) { 80 verifier->Fail(VERIFY_ERROR_BAD_CLASS_HARD) << "register v" << vsrc << " has type " << src_type 81 << " but expected " << check_type1; 82 return false; 83 } 84 const RegType& src_type_h = GetRegisterType(verifier, vsrc + 1); 85 if (!src_type.CheckWidePair(src_type_h)) { 86 verifier->Fail(VERIFY_ERROR_BAD_CLASS_HARD) << "wide register v" << vsrc << " has type " 87 << src_type << "/" << src_type_h; 88 return false; 89 } 90 // The register at vsrc has a defined type, we know the lower-upper-bound, but this is less 91 // precise than the subtype in vsrc so leave it for reference types. For primitive types 92 // if they are a defined type then they are as precise as we can get, however, for constant 93 // types we may wish to refine them. Unfortunately constant propagation has rendered this useless. 94 return true; 95 } 96 97 void RegisterLine::MarkRefsAsInitialized(MethodVerifier* verifier, const RegType& uninit_type) { 98 DCHECK(uninit_type.IsUninitializedTypes()); 99 const RegType& init_type = verifier->GetRegTypeCache()->FromUninitialized(uninit_type); 100 size_t changed = 0; 101 for (uint32_t i = 0; i < num_regs_; i++) { 102 if (GetRegisterType(verifier, i).Equals(uninit_type)) { 103 line_[i] = init_type.GetId(); 104 changed++; 105 } 106 } 107 // Is this initializing "this"? 108 if (uninit_type.IsUninitializedThisReference() || 109 uninit_type.IsUnresolvedAndUninitializedThisReference()) { 110 this_initialized_ = true; 111 } 112 DCHECK_GT(changed, 0u); 113 } 114 115 void RegisterLine::MarkAllRegistersAsConflicts(MethodVerifier* verifier) { 116 uint16_t conflict_type_id = verifier->GetRegTypeCache()->Conflict().GetId(); 117 for (uint32_t i = 0; i < num_regs_; i++) { 118 line_[i] = conflict_type_id; 119 } 120 } 121 122 void RegisterLine::MarkAllRegistersAsConflictsExcept(MethodVerifier* verifier, uint32_t vsrc) { 123 uint16_t conflict_type_id = verifier->GetRegTypeCache()->Conflict().GetId(); 124 for (uint32_t i = 0; i < num_regs_; i++) { 125 if (i != vsrc) { 126 line_[i] = conflict_type_id; 127 } 128 } 129 } 130 131 void RegisterLine::MarkAllRegistersAsConflictsExceptWide(MethodVerifier* verifier, uint32_t vsrc) { 132 uint16_t conflict_type_id = verifier->GetRegTypeCache()->Conflict().GetId(); 133 for (uint32_t i = 0; i < num_regs_; i++) { 134 if ((i != vsrc) && (i != (vsrc + 1))) { 135 line_[i] = conflict_type_id; 136 } 137 } 138 } 139 140 std::string RegisterLine::Dump(MethodVerifier* verifier) const { 141 std::string result; 142 for (size_t i = 0; i < num_regs_; i++) { 143 result += StringPrintf("%zd:[", i); 144 result += GetRegisterType(verifier, i).Dump(); 145 result += "],"; 146 } 147 for (const auto& monitor : monitors_) { 148 result += StringPrintf("{%d},", monitor); 149 } 150 for (auto& pairs : reg_to_lock_depths_) { 151 result += StringPrintf("<%d -> %" PRIx64 ">", 152 pairs.first, 153 static_cast<uint64_t>(pairs.second)); 154 } 155 return result; 156 } 157 158 void RegisterLine::MarkUninitRefsAsInvalid(MethodVerifier* verifier, const RegType& uninit_type) { 159 for (size_t i = 0; i < num_regs_; i++) { 160 if (GetRegisterType(verifier, i).Equals(uninit_type)) { 161 line_[i] = verifier->GetRegTypeCache()->Conflict().GetId(); 162 ClearAllRegToLockDepths(i); 163 } 164 } 165 } 166 167 void RegisterLine::CopyResultRegister1(MethodVerifier* verifier, uint32_t vdst, bool is_reference) { 168 const RegType& type = verifier->GetRegTypeCache()->GetFromId(result_[0]); 169 if ((!is_reference && !type.IsCategory1Types()) || 170 (is_reference && !type.IsReferenceTypes())) { 171 verifier->Fail(VERIFY_ERROR_BAD_CLASS_HARD) 172 << "copyRes1 v" << vdst << "<- result0" << " type=" << type; 173 } else { 174 DCHECK(verifier->GetRegTypeCache()->GetFromId(result_[1]).IsUndefined()); 175 SetRegisterType<LockOp::kClear>(verifier, vdst, type); 176 result_[0] = verifier->GetRegTypeCache()->Undefined().GetId(); 177 } 178 } 179 180 /* 181 * Implement "move-result-wide". Copy the category-2 value from the result 182 * register to another register, and reset the result register. 183 */ 184 void RegisterLine::CopyResultRegister2(MethodVerifier* verifier, uint32_t vdst) { 185 const RegType& type_l = verifier->GetRegTypeCache()->GetFromId(result_[0]); 186 const RegType& type_h = verifier->GetRegTypeCache()->GetFromId(result_[1]); 187 if (!type_l.IsCategory2Types()) { 188 verifier->Fail(VERIFY_ERROR_BAD_CLASS_HARD) 189 << "copyRes2 v" << vdst << "<- result0" << " type=" << type_l; 190 } else { 191 DCHECK(type_l.CheckWidePair(type_h)); // Set should never allow this case 192 SetRegisterTypeWide(verifier, vdst, type_l, type_h); // also sets the high 193 result_[0] = verifier->GetRegTypeCache()->Undefined().GetId(); 194 result_[1] = verifier->GetRegTypeCache()->Undefined().GetId(); 195 } 196 } 197 198 void RegisterLine::CheckUnaryOp(MethodVerifier* verifier, const Instruction* inst, 199 const RegType& dst_type, const RegType& src_type) { 200 if (VerifyRegisterType(verifier, inst->VRegB_12x(), src_type)) { 201 SetRegisterType<LockOp::kClear>(verifier, inst->VRegA_12x(), dst_type); 202 } 203 } 204 205 void RegisterLine::CheckUnaryOpWide(MethodVerifier* verifier, const Instruction* inst, 206 const RegType& dst_type1, const RegType& dst_type2, 207 const RegType& src_type1, const RegType& src_type2) { 208 if (VerifyRegisterTypeWide(verifier, inst->VRegB_12x(), src_type1, src_type2)) { 209 SetRegisterTypeWide(verifier, inst->VRegA_12x(), dst_type1, dst_type2); 210 } 211 } 212 213 void RegisterLine::CheckUnaryOpToWide(MethodVerifier* verifier, const Instruction* inst, 214 const RegType& dst_type1, const RegType& dst_type2, 215 const RegType& src_type) { 216 if (VerifyRegisterType(verifier, inst->VRegB_12x(), src_type)) { 217 SetRegisterTypeWide(verifier, inst->VRegA_12x(), dst_type1, dst_type2); 218 } 219 } 220 221 void RegisterLine::CheckUnaryOpFromWide(MethodVerifier* verifier, const Instruction* inst, 222 const RegType& dst_type, 223 const RegType& src_type1, const RegType& src_type2) { 224 if (VerifyRegisterTypeWide(verifier, inst->VRegB_12x(), src_type1, src_type2)) { 225 SetRegisterType<LockOp::kClear>(verifier, inst->VRegA_12x(), dst_type); 226 } 227 } 228 229 void RegisterLine::CheckBinaryOp(MethodVerifier* verifier, const Instruction* inst, 230 const RegType& dst_type, 231 const RegType& src_type1, const RegType& src_type2, 232 bool check_boolean_op) { 233 const uint32_t vregB = inst->VRegB_23x(); 234 const uint32_t vregC = inst->VRegC_23x(); 235 if (VerifyRegisterType(verifier, vregB, src_type1) && 236 VerifyRegisterType(verifier, vregC, src_type2)) { 237 if (check_boolean_op) { 238 DCHECK(dst_type.IsInteger()); 239 if (GetRegisterType(verifier, vregB).IsBooleanTypes() && 240 GetRegisterType(verifier, vregC).IsBooleanTypes()) { 241 SetRegisterType<LockOp::kClear>(verifier, 242 inst->VRegA_23x(), 243 verifier->GetRegTypeCache()->Boolean()); 244 return; 245 } 246 } 247 SetRegisterType<LockOp::kClear>(verifier, inst->VRegA_23x(), dst_type); 248 } 249 } 250 251 void RegisterLine::CheckBinaryOpWide(MethodVerifier* verifier, const Instruction* inst, 252 const RegType& dst_type1, const RegType& dst_type2, 253 const RegType& src_type1_1, const RegType& src_type1_2, 254 const RegType& src_type2_1, const RegType& src_type2_2) { 255 if (VerifyRegisterTypeWide(verifier, inst->VRegB_23x(), src_type1_1, src_type1_2) && 256 VerifyRegisterTypeWide(verifier, inst->VRegC_23x(), src_type2_1, src_type2_2)) { 257 SetRegisterTypeWide(verifier, inst->VRegA_23x(), dst_type1, dst_type2); 258 } 259 } 260 261 void RegisterLine::CheckBinaryOpWideShift(MethodVerifier* verifier, const Instruction* inst, 262 const RegType& long_lo_type, const RegType& long_hi_type, 263 const RegType& int_type) { 264 if (VerifyRegisterTypeWide(verifier, inst->VRegB_23x(), long_lo_type, long_hi_type) && 265 VerifyRegisterType(verifier, inst->VRegC_23x(), int_type)) { 266 SetRegisterTypeWide(verifier, inst->VRegA_23x(), long_lo_type, long_hi_type); 267 } 268 } 269 270 void RegisterLine::CheckBinaryOp2addr(MethodVerifier* verifier, const Instruction* inst, 271 const RegType& dst_type, const RegType& src_type1, 272 const RegType& src_type2, bool check_boolean_op) { 273 const uint32_t vregA = inst->VRegA_12x(); 274 const uint32_t vregB = inst->VRegB_12x(); 275 if (VerifyRegisterType(verifier, vregA, src_type1) && 276 VerifyRegisterType(verifier, vregB, src_type2)) { 277 if (check_boolean_op) { 278 DCHECK(dst_type.IsInteger()); 279 if (GetRegisterType(verifier, vregA).IsBooleanTypes() && 280 GetRegisterType(verifier, vregB).IsBooleanTypes()) { 281 SetRegisterType<LockOp::kClear>(verifier, 282 vregA, 283 verifier->GetRegTypeCache()->Boolean()); 284 return; 285 } 286 } 287 SetRegisterType<LockOp::kClear>(verifier, vregA, dst_type); 288 } 289 } 290 291 void RegisterLine::CheckBinaryOp2addrWide(MethodVerifier* verifier, const Instruction* inst, 292 const RegType& dst_type1, const RegType& dst_type2, 293 const RegType& src_type1_1, const RegType& src_type1_2, 294 const RegType& src_type2_1, const RegType& src_type2_2) { 295 const uint32_t vregA = inst->VRegA_12x(); 296 const uint32_t vregB = inst->VRegB_12x(); 297 if (VerifyRegisterTypeWide(verifier, vregA, src_type1_1, src_type1_2) && 298 VerifyRegisterTypeWide(verifier, vregB, src_type2_1, src_type2_2)) { 299 SetRegisterTypeWide(verifier, vregA, dst_type1, dst_type2); 300 } 301 } 302 303 void RegisterLine::CheckBinaryOp2addrWideShift(MethodVerifier* verifier, const Instruction* inst, 304 const RegType& long_lo_type, const RegType& long_hi_type, 305 const RegType& int_type) { 306 const uint32_t vregA = inst->VRegA_12x(); 307 const uint32_t vregB = inst->VRegB_12x(); 308 if (VerifyRegisterTypeWide(verifier, vregA, long_lo_type, long_hi_type) && 309 VerifyRegisterType(verifier, vregB, int_type)) { 310 SetRegisterTypeWide(verifier, vregA, long_lo_type, long_hi_type); 311 } 312 } 313 314 void RegisterLine::CheckLiteralOp(MethodVerifier* verifier, const Instruction* inst, 315 const RegType& dst_type, const RegType& src_type, 316 bool check_boolean_op, bool is_lit16) { 317 const uint32_t vregA = is_lit16 ? inst->VRegA_22s() : inst->VRegA_22b(); 318 const uint32_t vregB = is_lit16 ? inst->VRegB_22s() : inst->VRegB_22b(); 319 if (VerifyRegisterType(verifier, vregB, src_type)) { 320 if (check_boolean_op) { 321 DCHECK(dst_type.IsInteger()); 322 /* check vB with the call, then check the constant manually */ 323 const uint32_t val = is_lit16 ? inst->VRegC_22s() : inst->VRegC_22b(); 324 if (GetRegisterType(verifier, vregB).IsBooleanTypes() && (val == 0 || val == 1)) { 325 SetRegisterType<LockOp::kClear>(verifier, 326 vregA, 327 verifier->GetRegTypeCache()->Boolean()); 328 return; 329 } 330 } 331 SetRegisterType<LockOp::kClear>(verifier, vregA, dst_type); 332 } 333 } 334 335 static constexpr uint32_t kVirtualNullRegister = std::numeric_limits<uint32_t>::max(); 336 337 void RegisterLine::PushMonitor(MethodVerifier* verifier, uint32_t reg_idx, int32_t insn_idx) { 338 const RegType& reg_type = GetRegisterType(verifier, reg_idx); 339 if (!reg_type.IsReferenceTypes()) { 340 verifier->Fail(VERIFY_ERROR_BAD_CLASS_HARD) << "monitor-enter on non-object (" 341 << reg_type << ")"; 342 } else if (monitors_.size() >= kMaxMonitorStackDepth) { 343 verifier->Fail(VERIFY_ERROR_LOCKING); 344 if (kDumpLockFailures) { 345 VLOG(verifier) << "monitor-enter stack overflow while verifying " 346 << verifier->GetMethodReference().PrettyMethod(); 347 } 348 } else { 349 if (SetRegToLockDepth(reg_idx, monitors_.size())) { 350 // Null literals can establish aliases that we can't easily track. As such, handle the zero 351 // case as the 2^32-1 register (which isn't available in dex bytecode). 352 if (reg_type.IsZero()) { 353 SetRegToLockDepth(kVirtualNullRegister, monitors_.size()); 354 } 355 356 monitors_.push_back(insn_idx); 357 } else { 358 verifier->Fail(VERIFY_ERROR_LOCKING); 359 if (kDumpLockFailures) { 360 VLOG(verifier) << "unexpected monitor-enter on register v" << reg_idx << " in " 361 << verifier->GetMethodReference().PrettyMethod(); 362 } 363 } 364 } 365 } 366 367 void RegisterLine::PopMonitor(MethodVerifier* verifier, uint32_t reg_idx) { 368 const RegType& reg_type = GetRegisterType(verifier, reg_idx); 369 if (!reg_type.IsReferenceTypes()) { 370 verifier->Fail(VERIFY_ERROR_BAD_CLASS_HARD) << "monitor-exit on non-object (" << reg_type << ")"; 371 } else if (monitors_.empty()) { 372 verifier->Fail(VERIFY_ERROR_LOCKING); 373 if (kDumpLockFailures) { 374 VLOG(verifier) << "monitor-exit stack underflow while verifying " 375 << verifier->GetMethodReference().PrettyMethod(); 376 } 377 } else { 378 monitors_.pop_back(); 379 380 bool success = IsSetLockDepth(reg_idx, monitors_.size()); 381 382 if (!success && reg_type.IsZero()) { 383 // Null literals can establish aliases that we can't easily track. As such, handle the zero 384 // case as the 2^32-1 register (which isn't available in dex bytecode). 385 success = IsSetLockDepth(kVirtualNullRegister, monitors_.size()); 386 if (success) { 387 reg_idx = kVirtualNullRegister; 388 } 389 } 390 391 if (!success) { 392 verifier->Fail(VERIFY_ERROR_LOCKING); 393 if (kDumpLockFailures) { 394 VLOG(verifier) << "monitor-exit not unlocking the top of the monitor stack while verifying " 395 << verifier->GetMethodReference().PrettyMethod(); 396 } 397 } else { 398 // Record the register was unlocked. This clears all aliases, thus it will also clear the 399 // null lock, if necessary. 400 ClearRegToLockDepth(reg_idx, monitors_.size()); 401 } 402 } 403 } 404 405 bool FindLockAliasedRegister(uint32_t src, 406 const RegisterLine::RegToLockDepthsMap& src_map, 407 const RegisterLine::RegToLockDepthsMap& search_map) { 408 auto it = src_map.find(src); 409 if (it == src_map.end()) { 410 // "Not locked" is trivially aliased. 411 return true; 412 } 413 uint32_t src_lock_levels = it->second; 414 if (src_lock_levels == 0) { 415 // "Not locked" is trivially aliased. 416 return true; 417 } 418 419 // Scan the map for the same value. 420 for (const std::pair<const uint32_t, uint32_t>& pair : search_map) { 421 if (pair.first != src && pair.second == src_lock_levels) { 422 return true; 423 } 424 } 425 426 // Nothing found, no alias. 427 return false; 428 } 429 430 bool RegisterLine::MergeRegisters(MethodVerifier* verifier, const RegisterLine* incoming_line) { 431 bool changed = false; 432 DCHECK(incoming_line != nullptr); 433 for (size_t idx = 0; idx < num_regs_; idx++) { 434 if (line_[idx] != incoming_line->line_[idx]) { 435 const RegType& incoming_reg_type = incoming_line->GetRegisterType(verifier, idx); 436 const RegType& cur_type = GetRegisterType(verifier, idx); 437 const RegType& new_type = cur_type.Merge( 438 incoming_reg_type, verifier->GetRegTypeCache(), verifier); 439 changed = changed || !cur_type.Equals(new_type); 440 line_[idx] = new_type.GetId(); 441 } 442 } 443 if (monitors_.size() > 0 || incoming_line->monitors_.size() > 0) { 444 if (monitors_.size() != incoming_line->monitors_.size()) { 445 verifier->Fail(VERIFY_ERROR_LOCKING); 446 if (kDumpLockFailures) { 447 VLOG(verifier) << "mismatched stack depths (depth=" << MonitorStackDepth() 448 << ", incoming depth=" << incoming_line->MonitorStackDepth() << ") in " 449 << verifier->GetMethodReference().PrettyMethod(); 450 } 451 } else if (reg_to_lock_depths_ != incoming_line->reg_to_lock_depths_) { 452 for (uint32_t idx = 0; idx < num_regs_; idx++) { 453 size_t depths = reg_to_lock_depths_.count(idx); 454 size_t incoming_depths = incoming_line->reg_to_lock_depths_.count(idx); 455 if (depths != incoming_depths) { 456 // Stack levels aren't matching. This is potentially bad, as we don't do a 457 // flow-sensitive analysis. 458 // However, this could be an alias of something locked in one path, and the alias was 459 // destroyed in another path. It is fine to drop this as long as there's another alias 460 // for the lock around. The last vanishing alias will then report that things would be 461 // left unlocked. We need to check for aliases for both lock levels. 462 // 463 // Example (lock status in curly braces as pair of register and lock leels): 464 // 465 // lock v1 {v1=1} 466 // | | 467 // v0 = v1 {v0=1, v1=1} v0 = v2 {v1=1} 468 // | | 469 // {v1=1} 470 // // Dropping v0, as the status can't be merged 471 // // but the lock info ("locked at depth 1" and) 472 // // "not locked at all") is available. 473 if (!FindLockAliasedRegister(idx, 474 reg_to_lock_depths_, 475 reg_to_lock_depths_) || 476 !FindLockAliasedRegister(idx, 477 incoming_line->reg_to_lock_depths_, 478 reg_to_lock_depths_)) { 479 verifier->Fail(VERIFY_ERROR_LOCKING); 480 if (kDumpLockFailures) { 481 VLOG(verifier) << "mismatched stack depths for register v" << idx 482 << ": " << depths << " != " << incoming_depths << " in " 483 << verifier->GetMethodReference().PrettyMethod(); 484 } 485 break; 486 } 487 // We found aliases, set this to zero. 488 reg_to_lock_depths_.erase(idx); 489 } else if (depths > 0) { 490 // Check whether they're actually the same levels. 491 uint32_t locked_levels = reg_to_lock_depths_.find(idx)->second; 492 uint32_t incoming_locked_levels = incoming_line->reg_to_lock_depths_.find(idx)->second; 493 if (locked_levels != incoming_locked_levels) { 494 // Lock levels aren't matching. This is potentially bad, as we don't do a 495 // flow-sensitive analysis. 496 // However, this could be an alias of something locked in one path, and the alias was 497 // destroyed in another path. It is fine to drop this as long as there's another alias 498 // for the lock around. The last vanishing alias will then report that things would be 499 // left unlocked. We need to check for aliases for both lock levels. 500 // 501 // Example (lock status in curly braces as pair of register and lock leels): 502 // 503 // lock v1 {v1=1} 504 // lock v2 {v1=1, v2=2} 505 // | | 506 // v0 = v1 {v0=1, v1=1, v2=2} v0 = v2 {v0=2, v1=1, v2=2} 507 // | | 508 // {v1=1, v2=2} 509 // // Dropping v0, as the status can't be 510 // // merged but the lock info ("locked at 511 // // depth 1" and "locked at depth 2") is 512 // // available. 513 if (!FindLockAliasedRegister(idx, 514 reg_to_lock_depths_, 515 reg_to_lock_depths_) || 516 !FindLockAliasedRegister(idx, 517 incoming_line->reg_to_lock_depths_, 518 reg_to_lock_depths_)) { 519 // No aliases for both current and incoming, we'll lose information. 520 verifier->Fail(VERIFY_ERROR_LOCKING); 521 if (kDumpLockFailures) { 522 VLOG(verifier) << "mismatched lock levels for register v" << idx << ": " 523 << std::hex << locked_levels << std::dec << " != " 524 << std::hex << incoming_locked_levels << std::dec << " in " 525 << verifier->GetMethodReference().PrettyMethod(); 526 } 527 break; 528 } 529 // We found aliases, set this to zero. 530 reg_to_lock_depths_.erase(idx); 531 } 532 } 533 } 534 } 535 } 536 537 // Check whether "this" was initialized in both paths. 538 if (this_initialized_ && !incoming_line->this_initialized_) { 539 this_initialized_ = false; 540 changed = true; 541 } 542 return changed; 543 } 544 545 } // namespace verifier 546 } // namespace art 547