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 "reg_type-inl.h" 18 19#include "android-base/stringprintf.h" 20 21#include "base/arena_bit_vector.h" 22#include "base/bit_vector-inl.h" 23#include "base/casts.h" 24#include "class_linker-inl.h" 25#include "dex_file-inl.h" 26#include "method_verifier.h" 27#include "mirror/class.h" 28#include "mirror/class-inl.h" 29#include "mirror/object-inl.h" 30#include "mirror/object_array-inl.h" 31#include "reg_type_cache-inl.h" 32#include "scoped_thread_state_change-inl.h" 33 34#include <limits> 35#include <sstream> 36 37namespace art { 38namespace verifier { 39 40using android::base::StringPrintf; 41 42const UndefinedType* UndefinedType::instance_ = nullptr; 43const ConflictType* ConflictType::instance_ = nullptr; 44const BooleanType* BooleanType::instance_ = nullptr; 45const ByteType* ByteType::instance_ = nullptr; 46const ShortType* ShortType::instance_ = nullptr; 47const CharType* CharType::instance_ = nullptr; 48const FloatType* FloatType::instance_ = nullptr; 49const LongLoType* LongLoType::instance_ = nullptr; 50const LongHiType* LongHiType::instance_ = nullptr; 51const DoubleLoType* DoubleLoType::instance_ = nullptr; 52const DoubleHiType* DoubleHiType::instance_ = nullptr; 53const IntegerType* IntegerType::instance_ = nullptr; 54 55PrimitiveType::PrimitiveType(mirror::Class* klass, const StringPiece& descriptor, uint16_t cache_id) 56 : RegType(klass, descriptor, cache_id) { 57 CHECK(klass != nullptr); 58 CHECK(!descriptor.empty()); 59} 60 61Cat1Type::Cat1Type(mirror::Class* klass, const StringPiece& descriptor, uint16_t cache_id) 62 : PrimitiveType(klass, descriptor, cache_id) { 63} 64 65Cat2Type::Cat2Type(mirror::Class* klass, const StringPiece& descriptor, uint16_t cache_id) 66 : PrimitiveType(klass, descriptor, cache_id) { 67} 68 69std::string PreciseConstType::Dump() const { 70 std::stringstream result; 71 uint32_t val = ConstantValue(); 72 if (val == 0) { 73 CHECK(IsPreciseConstant()); 74 result << "Zero/null"; 75 } else { 76 result << "Precise "; 77 if (IsConstantShort()) { 78 result << StringPrintf("Constant: %d", val); 79 } else { 80 result << StringPrintf("Constant: 0x%x", val); 81 } 82 } 83 return result.str(); 84} 85 86std::string BooleanType::Dump() const { 87 return "Boolean"; 88} 89 90std::string ConflictType::Dump() const { 91 return "Conflict"; 92} 93 94std::string ByteType::Dump() const { 95 return "Byte"; 96} 97 98std::string ShortType::Dump() const { 99 return "Short"; 100} 101 102std::string CharType::Dump() const { 103 return "Char"; 104} 105 106std::string FloatType::Dump() const { 107 return "Float"; 108} 109 110std::string LongLoType::Dump() const { 111 return "Long (Low Half)"; 112} 113 114std::string LongHiType::Dump() const { 115 return "Long (High Half)"; 116} 117 118std::string DoubleLoType::Dump() const { 119 return "Double (Low Half)"; 120} 121 122std::string DoubleHiType::Dump() const { 123 return "Double (High Half)"; 124} 125 126std::string IntegerType::Dump() const { 127 return "Integer"; 128} 129 130const DoubleHiType* DoubleHiType::CreateInstance(mirror::Class* klass, 131 const StringPiece& descriptor, 132 uint16_t cache_id) { 133 CHECK(instance_ == nullptr); 134 instance_ = new DoubleHiType(klass, descriptor, cache_id); 135 return instance_; 136} 137 138void DoubleHiType::Destroy() { 139 if (instance_ != nullptr) { 140 delete instance_; 141 instance_ = nullptr; 142 } 143} 144 145const DoubleLoType* DoubleLoType::CreateInstance(mirror::Class* klass, 146 const StringPiece& descriptor, 147 uint16_t cache_id) { 148 CHECK(instance_ == nullptr); 149 instance_ = new DoubleLoType(klass, descriptor, cache_id); 150 return instance_; 151} 152 153void DoubleLoType::Destroy() { 154 if (instance_ != nullptr) { 155 delete instance_; 156 instance_ = nullptr; 157 } 158} 159 160const LongLoType* LongLoType::CreateInstance(mirror::Class* klass, const StringPiece& descriptor, 161 uint16_t cache_id) { 162 CHECK(instance_ == nullptr); 163 instance_ = new LongLoType(klass, descriptor, cache_id); 164 return instance_; 165} 166 167const LongHiType* LongHiType::CreateInstance(mirror::Class* klass, const StringPiece& descriptor, 168 uint16_t cache_id) { 169 CHECK(instance_ == nullptr); 170 instance_ = new LongHiType(klass, descriptor, cache_id); 171 return instance_; 172} 173 174void LongHiType::Destroy() { 175 if (instance_ != nullptr) { 176 delete instance_; 177 instance_ = nullptr; 178 } 179} 180 181void LongLoType::Destroy() { 182 if (instance_ != nullptr) { 183 delete instance_; 184 instance_ = nullptr; 185 } 186} 187 188const FloatType* FloatType::CreateInstance(mirror::Class* klass, const StringPiece& descriptor, 189 uint16_t cache_id) { 190 CHECK(instance_ == nullptr); 191 instance_ = new FloatType(klass, descriptor, cache_id); 192 return instance_; 193} 194 195void FloatType::Destroy() { 196 if (instance_ != nullptr) { 197 delete instance_; 198 instance_ = nullptr; 199 } 200} 201 202const CharType* CharType::CreateInstance(mirror::Class* klass, const StringPiece& descriptor, 203 uint16_t cache_id) { 204 CHECK(instance_ == nullptr); 205 instance_ = new CharType(klass, descriptor, cache_id); 206 return instance_; 207} 208 209void CharType::Destroy() { 210 if (instance_ != nullptr) { 211 delete instance_; 212 instance_ = nullptr; 213 } 214} 215 216const ShortType* ShortType::CreateInstance(mirror::Class* klass, const StringPiece& descriptor, 217 uint16_t cache_id) { 218 CHECK(instance_ == nullptr); 219 instance_ = new ShortType(klass, descriptor, cache_id); 220 return instance_; 221} 222 223void ShortType::Destroy() { 224 if (instance_ != nullptr) { 225 delete instance_; 226 instance_ = nullptr; 227 } 228} 229 230const ByteType* ByteType::CreateInstance(mirror::Class* klass, const StringPiece& descriptor, 231 uint16_t cache_id) { 232 CHECK(instance_ == nullptr); 233 instance_ = new ByteType(klass, descriptor, cache_id); 234 return instance_; 235} 236 237void ByteType::Destroy() { 238 if (instance_ != nullptr) { 239 delete instance_; 240 instance_ = nullptr; 241 } 242} 243 244const IntegerType* IntegerType::CreateInstance(mirror::Class* klass, const StringPiece& descriptor, 245 uint16_t cache_id) { 246 CHECK(instance_ == nullptr); 247 instance_ = new IntegerType(klass, descriptor, cache_id); 248 return instance_; 249} 250 251void IntegerType::Destroy() { 252 if (instance_ != nullptr) { 253 delete instance_; 254 instance_ = nullptr; 255 } 256} 257 258const ConflictType* ConflictType::CreateInstance(mirror::Class* klass, 259 const StringPiece& descriptor, 260 uint16_t cache_id) { 261 CHECK(instance_ == nullptr); 262 instance_ = new ConflictType(klass, descriptor, cache_id); 263 return instance_; 264} 265 266void ConflictType::Destroy() { 267 if (instance_ != nullptr) { 268 delete instance_; 269 instance_ = nullptr; 270 } 271} 272 273const BooleanType* BooleanType::CreateInstance(mirror::Class* klass, const StringPiece& descriptor, 274 uint16_t cache_id) { 275 CHECK(BooleanType::instance_ == nullptr); 276 instance_ = new BooleanType(klass, descriptor, cache_id); 277 return BooleanType::instance_; 278} 279 280void BooleanType::Destroy() { 281 if (BooleanType::instance_ != nullptr) { 282 delete instance_; 283 instance_ = nullptr; 284 } 285} 286 287std::string UndefinedType::Dump() const REQUIRES_SHARED(Locks::mutator_lock_) { 288 return "Undefined"; 289} 290 291const UndefinedType* UndefinedType::CreateInstance(mirror::Class* klass, 292 const StringPiece& descriptor, 293 uint16_t cache_id) { 294 CHECK(instance_ == nullptr); 295 instance_ = new UndefinedType(klass, descriptor, cache_id); 296 return instance_; 297} 298 299void UndefinedType::Destroy() { 300 if (instance_ != nullptr) { 301 delete instance_; 302 instance_ = nullptr; 303 } 304} 305 306PreciseReferenceType::PreciseReferenceType(mirror::Class* klass, const StringPiece& descriptor, 307 uint16_t cache_id) 308 : RegType(klass, descriptor, cache_id) { 309 // Note: no check for IsInstantiable() here. We may produce this in case an InstantiationError 310 // would be thrown at runtime, but we need to continue verification and *not* create a 311 // hard failure or abort. 312 CheckConstructorInvariants(this); 313} 314 315std::string UnresolvedMergedType::Dump() const { 316 std::stringstream result; 317 result << "UnresolvedMergedReferences(" << GetResolvedPart().Dump() << " | "; 318 const BitVector& types = GetUnresolvedTypes(); 319 320 bool first = true; 321 for (uint32_t idx : types.Indexes()) { 322 if (!first) { 323 result << ", "; 324 } else { 325 first = false; 326 } 327 result << reg_type_cache_->GetFromId(idx).Dump(); 328 } 329 result << ")"; 330 return result.str(); 331} 332 333std::string UnresolvedSuperClass::Dump() const { 334 std::stringstream result; 335 uint16_t super_type_id = GetUnresolvedSuperClassChildId(); 336 result << "UnresolvedSuperClass(" << reg_type_cache_->GetFromId(super_type_id).Dump() << ")"; 337 return result.str(); 338} 339 340std::string UnresolvedReferenceType::Dump() const { 341 std::stringstream result; 342 result << "Unresolved Reference" << ": " << PrettyDescriptor(GetDescriptor().as_string().c_str()); 343 return result.str(); 344} 345 346std::string UnresolvedUninitializedRefType::Dump() const { 347 std::stringstream result; 348 result << "Unresolved And Uninitialized Reference" << ": " 349 << PrettyDescriptor(GetDescriptor().as_string().c_str()) 350 << " Allocation PC: " << GetAllocationPc(); 351 return result.str(); 352} 353 354std::string UnresolvedUninitializedThisRefType::Dump() const { 355 std::stringstream result; 356 result << "Unresolved And Uninitialized This Reference" 357 << PrettyDescriptor(GetDescriptor().as_string().c_str()); 358 return result.str(); 359} 360 361std::string ReferenceType::Dump() const { 362 std::stringstream result; 363 result << "Reference" << ": " << mirror::Class::PrettyDescriptor(GetClass()); 364 return result.str(); 365} 366 367std::string PreciseReferenceType::Dump() const { 368 std::stringstream result; 369 result << "Precise Reference" << ": "<< mirror::Class::PrettyDescriptor(GetClass()); 370 return result.str(); 371} 372 373std::string UninitializedReferenceType::Dump() const { 374 std::stringstream result; 375 result << "Uninitialized Reference" << ": " << mirror::Class::PrettyDescriptor(GetClass()); 376 result << " Allocation PC: " << GetAllocationPc(); 377 return result.str(); 378} 379 380std::string UninitializedThisReferenceType::Dump() const { 381 std::stringstream result; 382 result << "Uninitialized This Reference" << ": " << mirror::Class::PrettyDescriptor(GetClass()); 383 result << "Allocation PC: " << GetAllocationPc(); 384 return result.str(); 385} 386 387std::string ImpreciseConstType::Dump() const { 388 std::stringstream result; 389 uint32_t val = ConstantValue(); 390 if (val == 0) { 391 result << "Zero/null"; 392 } else { 393 result << "Imprecise "; 394 if (IsConstantShort()) { 395 result << StringPrintf("Constant: %d", val); 396 } else { 397 result << StringPrintf("Constant: 0x%x", val); 398 } 399 } 400 return result.str(); 401} 402std::string PreciseConstLoType::Dump() const { 403 std::stringstream result; 404 405 int32_t val = ConstantValueLo(); 406 result << "Precise "; 407 if (val >= std::numeric_limits<jshort>::min() && 408 val <= std::numeric_limits<jshort>::max()) { 409 result << StringPrintf("Low-half Constant: %d", val); 410 } else { 411 result << StringPrintf("Low-half Constant: 0x%x", val); 412 } 413 return result.str(); 414} 415 416std::string ImpreciseConstLoType::Dump() const { 417 std::stringstream result; 418 419 int32_t val = ConstantValueLo(); 420 result << "Imprecise "; 421 if (val >= std::numeric_limits<jshort>::min() && 422 val <= std::numeric_limits<jshort>::max()) { 423 result << StringPrintf("Low-half Constant: %d", val); 424 } else { 425 result << StringPrintf("Low-half Constant: 0x%x", val); 426 } 427 return result.str(); 428} 429 430std::string PreciseConstHiType::Dump() const { 431 std::stringstream result; 432 int32_t val = ConstantValueHi(); 433 result << "Precise "; 434 if (val >= std::numeric_limits<jshort>::min() && 435 val <= std::numeric_limits<jshort>::max()) { 436 result << StringPrintf("High-half Constant: %d", val); 437 } else { 438 result << StringPrintf("High-half Constant: 0x%x", val); 439 } 440 return result.str(); 441} 442 443std::string ImpreciseConstHiType::Dump() const { 444 std::stringstream result; 445 int32_t val = ConstantValueHi(); 446 result << "Imprecise "; 447 if (val >= std::numeric_limits<jshort>::min() && 448 val <= std::numeric_limits<jshort>::max()) { 449 result << StringPrintf("High-half Constant: %d", val); 450 } else { 451 result << StringPrintf("High-half Constant: 0x%x", val); 452 } 453 return result.str(); 454} 455 456const RegType& RegType::HighHalf(RegTypeCache* cache) const { 457 DCHECK(IsLowHalf()); 458 if (IsLongLo()) { 459 return cache->LongHi(); 460 } else if (IsDoubleLo()) { 461 return cache->DoubleHi(); 462 } else { 463 DCHECK(IsImpreciseConstantLo()); 464 const ConstantType* const_val = down_cast<const ConstantType*>(this); 465 return cache->FromCat2ConstHi(const_val->ConstantValue(), false); 466 } 467} 468 469Primitive::Type RegType::GetPrimitiveType() const { 470 if (IsNonZeroReferenceTypes()) { 471 return Primitive::kPrimNot; 472 } else if (IsBooleanTypes()) { 473 return Primitive::kPrimBoolean; 474 } else if (IsByteTypes()) { 475 return Primitive::kPrimByte; 476 } else if (IsShortTypes()) { 477 return Primitive::kPrimShort; 478 } else if (IsCharTypes()) { 479 return Primitive::kPrimChar; 480 } else if (IsFloat()) { 481 return Primitive::kPrimFloat; 482 } else if (IsIntegralTypes()) { 483 return Primitive::kPrimInt; 484 } else if (IsDoubleLo()) { 485 return Primitive::kPrimDouble; 486 } else { 487 DCHECK(IsLongTypes()); 488 return Primitive::kPrimLong; 489 } 490} 491 492bool UninitializedType::IsUninitializedTypes() const { 493 return true; 494} 495 496bool UninitializedType::IsNonZeroReferenceTypes() const { 497 return true; 498} 499 500bool UnresolvedType::IsNonZeroReferenceTypes() const { 501 return true; 502} 503 504const RegType& RegType::GetSuperClass(RegTypeCache* cache) const { 505 if (!IsUnresolvedTypes()) { 506 mirror::Class* super_klass = GetClass()->GetSuperClass(); 507 if (super_klass != nullptr) { 508 // A super class of a precise type isn't precise as a precise type indicates the register 509 // holds exactly that type. 510 std::string temp; 511 return cache->FromClass(super_klass->GetDescriptor(&temp), super_klass, false); 512 } else { 513 return cache->Zero(); 514 } 515 } else { 516 if (!IsUnresolvedMergedReference() && !IsUnresolvedSuperClass() && 517 GetDescriptor()[0] == '[') { 518 // Super class of all arrays is Object. 519 return cache->JavaLangObject(true); 520 } else { 521 return cache->FromUnresolvedSuperClass(*this); 522 } 523 } 524} 525 526bool RegType::IsJavaLangObject() const REQUIRES_SHARED(Locks::mutator_lock_) { 527 return IsReference() && GetClass()->IsObjectClass(); 528} 529 530bool RegType::IsObjectArrayTypes() const REQUIRES_SHARED(Locks::mutator_lock_) { 531 if (IsUnresolvedTypes()) { 532 DCHECK(!IsUnresolvedMergedReference()); 533 534 if (IsUnresolvedSuperClass()) { 535 // Cannot be an array, as the superclass of arrays is java.lang.Object (which cannot be 536 // unresolved). 537 return false; 538 } 539 540 // Primitive arrays will always resolve. 541 DCHECK(descriptor_[1] == 'L' || descriptor_[1] == '['); 542 return descriptor_[0] == '['; 543 } else if (HasClass()) { 544 mirror::Class* type = GetClass(); 545 return type->IsArrayClass() && !type->GetComponentType()->IsPrimitive(); 546 } else { 547 return false; 548 } 549} 550 551bool RegType::IsArrayTypes() const REQUIRES_SHARED(Locks::mutator_lock_) { 552 if (IsUnresolvedTypes()) { 553 DCHECK(!IsUnresolvedMergedReference()); 554 555 if (IsUnresolvedSuperClass()) { 556 // Cannot be an array, as the superclass of arrays is java.lang.Object (which cannot be 557 // unresolved). 558 return false; 559 } 560 return descriptor_[0] == '['; 561 } else if (HasClass()) { 562 return GetClass()->IsArrayClass(); 563 } else { 564 return false; 565 } 566} 567 568bool RegType::IsJavaLangObjectArray() const { 569 if (HasClass()) { 570 mirror::Class* type = GetClass(); 571 return type->IsArrayClass() && type->GetComponentType()->IsObjectClass(); 572 } 573 return false; 574} 575 576bool RegType::IsInstantiableTypes() const { 577 return IsUnresolvedTypes() || (IsNonZeroReferenceTypes() && GetClass()->IsInstantiable()); 578} 579 580static const RegType& SelectNonConstant(const RegType& a, const RegType& b) { 581 return a.IsConstantTypes() ? b : a; 582} 583 584const RegType& RegType::Merge(const RegType& incoming_type, 585 RegTypeCache* reg_types, 586 MethodVerifier* verifier) const { 587 DCHECK(!Equals(incoming_type)); // Trivial equality handled by caller 588 // Perform pointer equality tests for undefined and conflict to avoid virtual method dispatch. 589 const UndefinedType& undefined = reg_types->Undefined(); 590 const ConflictType& conflict = reg_types->Conflict(); 591 DCHECK_EQ(this == &undefined, IsUndefined()); 592 DCHECK_EQ(&incoming_type == &undefined, incoming_type.IsUndefined()); 593 DCHECK_EQ(this == &conflict, IsConflict()); 594 DCHECK_EQ(&incoming_type == &conflict, incoming_type.IsConflict()); 595 if (this == &undefined || &incoming_type == &undefined) { 596 // There is a difference between undefined and conflict. Conflicts may be copied around, but 597 // not used. Undefined registers must not be copied. So any merge with undefined should return 598 // undefined. 599 return undefined; 600 } else if (this == &conflict || &incoming_type == &conflict) { 601 return conflict; // (Conflict MERGE *) or (* MERGE Conflict) => Conflict 602 } else if (IsConstant() && incoming_type.IsConstant()) { 603 const ConstantType& type1 = *down_cast<const ConstantType*>(this); 604 const ConstantType& type2 = *down_cast<const ConstantType*>(&incoming_type); 605 int32_t val1 = type1.ConstantValue(); 606 int32_t val2 = type2.ConstantValue(); 607 if (val1 >= 0 && val2 >= 0) { 608 // +ve1 MERGE +ve2 => MAX(+ve1, +ve2) 609 if (val1 >= val2) { 610 if (!type1.IsPreciseConstant()) { 611 return *this; 612 } else { 613 return reg_types->FromCat1Const(val1, false); 614 } 615 } else { 616 if (!type2.IsPreciseConstant()) { 617 return type2; 618 } else { 619 return reg_types->FromCat1Const(val2, false); 620 } 621 } 622 } else if (val1 < 0 && val2 < 0) { 623 // -ve1 MERGE -ve2 => MIN(-ve1, -ve2) 624 if (val1 <= val2) { 625 if (!type1.IsPreciseConstant()) { 626 return *this; 627 } else { 628 return reg_types->FromCat1Const(val1, false); 629 } 630 } else { 631 if (!type2.IsPreciseConstant()) { 632 return type2; 633 } else { 634 return reg_types->FromCat1Const(val2, false); 635 } 636 } 637 } else { 638 // Values are +ve and -ve, choose smallest signed type in which they both fit 639 if (type1.IsConstantByte()) { 640 if (type2.IsConstantByte()) { 641 return reg_types->ByteConstant(); 642 } else if (type2.IsConstantShort()) { 643 return reg_types->ShortConstant(); 644 } else { 645 return reg_types->IntConstant(); 646 } 647 } else if (type1.IsConstantShort()) { 648 if (type2.IsConstantShort()) { 649 return reg_types->ShortConstant(); 650 } else { 651 return reg_types->IntConstant(); 652 } 653 } else { 654 return reg_types->IntConstant(); 655 } 656 } 657 } else if (IsConstantLo() && incoming_type.IsConstantLo()) { 658 const ConstantType& type1 = *down_cast<const ConstantType*>(this); 659 const ConstantType& type2 = *down_cast<const ConstantType*>(&incoming_type); 660 int32_t val1 = type1.ConstantValueLo(); 661 int32_t val2 = type2.ConstantValueLo(); 662 return reg_types->FromCat2ConstLo(val1 | val2, false); 663 } else if (IsConstantHi() && incoming_type.IsConstantHi()) { 664 const ConstantType& type1 = *down_cast<const ConstantType*>(this); 665 const ConstantType& type2 = *down_cast<const ConstantType*>(&incoming_type); 666 int32_t val1 = type1.ConstantValueHi(); 667 int32_t val2 = type2.ConstantValueHi(); 668 return reg_types->FromCat2ConstHi(val1 | val2, false); 669 } else if (IsIntegralTypes() && incoming_type.IsIntegralTypes()) { 670 if (IsBooleanTypes() && incoming_type.IsBooleanTypes()) { 671 return reg_types->Boolean(); // boolean MERGE boolean => boolean 672 } 673 if (IsByteTypes() && incoming_type.IsByteTypes()) { 674 return reg_types->Byte(); // byte MERGE byte => byte 675 } 676 if (IsShortTypes() && incoming_type.IsShortTypes()) { 677 return reg_types->Short(); // short MERGE short => short 678 } 679 if (IsCharTypes() && incoming_type.IsCharTypes()) { 680 return reg_types->Char(); // char MERGE char => char 681 } 682 return reg_types->Integer(); // int MERGE * => int 683 } else if ((IsFloatTypes() && incoming_type.IsFloatTypes()) || 684 (IsLongTypes() && incoming_type.IsLongTypes()) || 685 (IsLongHighTypes() && incoming_type.IsLongHighTypes()) || 686 (IsDoubleTypes() && incoming_type.IsDoubleTypes()) || 687 (IsDoubleHighTypes() && incoming_type.IsDoubleHighTypes())) { 688 // check constant case was handled prior to entry 689 DCHECK(!IsConstant() || !incoming_type.IsConstant()); 690 // float/long/double MERGE float/long/double_constant => float/long/double 691 return SelectNonConstant(*this, incoming_type); 692 } else if (IsReferenceTypes() && incoming_type.IsReferenceTypes()) { 693 if (IsUninitializedTypes() || incoming_type.IsUninitializedTypes()) { 694 // Something that is uninitialized hasn't had its constructor called. Unitialized types are 695 // special. They may only ever be merged with themselves (must be taken care of by the 696 // caller of Merge(), see the DCHECK on entry). So mark any other merge as conflicting here. 697 return conflict; 698 } else if (IsZero() || incoming_type.IsZero()) { 699 return SelectNonConstant(*this, incoming_type); // 0 MERGE ref => ref 700 } else if (IsJavaLangObject() || incoming_type.IsJavaLangObject()) { 701 return reg_types->JavaLangObject(false); // Object MERGE ref => Object 702 } else if (IsUnresolvedTypes() || incoming_type.IsUnresolvedTypes()) { 703 // We know how to merge an unresolved type with itself, 0 or Object. In this case we 704 // have two sub-classes and don't know how to merge. Create a new string-based unresolved 705 // type that reflects our lack of knowledge and that allows the rest of the unresolved 706 // mechanics to continue. 707 return reg_types->FromUnresolvedMerge(*this, incoming_type, verifier); 708 } else { // Two reference types, compute Join 709 mirror::Class* c1 = GetClass(); 710 mirror::Class* c2 = incoming_type.GetClass(); 711 DCHECK(c1 != nullptr && !c1->IsPrimitive()); 712 DCHECK(c2 != nullptr && !c2->IsPrimitive()); 713 mirror::Class* join_class = ClassJoin(c1, c2); 714 // Record the dependency that both `c1` and `c2` are assignable to `join_class`. 715 // The `verifier` is null during unit tests. 716 if (verifier != nullptr) { 717 VerifierDeps::MaybeRecordAssignability( 718 verifier->GetDexFile(), join_class, c1, true /* strict */, true /* is_assignable */); 719 VerifierDeps::MaybeRecordAssignability( 720 verifier->GetDexFile(), join_class, c2, true /* strict */, true /* is_assignable */); 721 } 722 if (c1 == join_class && !IsPreciseReference()) { 723 return *this; 724 } else if (c2 == join_class && !incoming_type.IsPreciseReference()) { 725 return incoming_type; 726 } else { 727 std::string temp; 728 return reg_types->FromClass(join_class->GetDescriptor(&temp), join_class, false); 729 } 730 } 731 } else { 732 return conflict; // Unexpected types => Conflict 733 } 734} 735 736// See comment in reg_type.h 737mirror::Class* RegType::ClassJoin(mirror::Class* s, mirror::Class* t) { 738 DCHECK(!s->IsPrimitive()) << s->PrettyClass(); 739 DCHECK(!t->IsPrimitive()) << t->PrettyClass(); 740 if (s == t) { 741 return s; 742 } else if (s->IsAssignableFrom(t)) { 743 return s; 744 } else if (t->IsAssignableFrom(s)) { 745 return t; 746 } else if (s->IsArrayClass() && t->IsArrayClass()) { 747 mirror::Class* s_ct = s->GetComponentType(); 748 mirror::Class* t_ct = t->GetComponentType(); 749 if (s_ct->IsPrimitive() || t_ct->IsPrimitive()) { 750 // Given the types aren't the same, if either array is of primitive types then the only 751 // common parent is java.lang.Object 752 mirror::Class* result = s->GetSuperClass(); // short-cut to java.lang.Object 753 DCHECK(result->IsObjectClass()); 754 return result; 755 } 756 ObjPtr<mirror::Class> common_elem = ClassJoin(s_ct, t_ct); 757 ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); 758 mirror::Class* array_class = class_linker->FindArrayClass(Thread::Current(), &common_elem); 759 DCHECK(array_class != nullptr); 760 return array_class; 761 } else { 762 size_t s_depth = s->Depth(); 763 size_t t_depth = t->Depth(); 764 // Get s and t to the same depth in the hierarchy 765 if (s_depth > t_depth) { 766 while (s_depth > t_depth) { 767 s = s->GetSuperClass(); 768 s_depth--; 769 } 770 } else { 771 while (t_depth > s_depth) { 772 t = t->GetSuperClass(); 773 t_depth--; 774 } 775 } 776 // Go up the hierarchy until we get to the common parent 777 while (s != t) { 778 s = s->GetSuperClass(); 779 t = t->GetSuperClass(); 780 } 781 return s; 782 } 783} 784 785void RegType::CheckInvariants() const { 786 if (IsConstant() || IsConstantLo() || IsConstantHi()) { 787 CHECK(descriptor_.empty()) << *this; 788 CHECK(klass_.IsNull()) << *this; 789 } 790 if (!klass_.IsNull()) { 791 CHECK(!descriptor_.empty()) << *this; 792 std::string temp; 793 CHECK_EQ(descriptor_, klass_.Read()->GetDescriptor(&temp)) << *this; 794 } 795} 796 797void RegType::VisitRoots(RootVisitor* visitor, const RootInfo& root_info) const { 798 klass_.VisitRootIfNonNull(visitor, root_info); 799} 800 801void UninitializedThisReferenceType::CheckInvariants() const { 802 CHECK_EQ(GetAllocationPc(), 0U) << *this; 803} 804 805void UnresolvedUninitializedThisRefType::CheckInvariants() const { 806 CHECK_EQ(GetAllocationPc(), 0U) << *this; 807 CHECK(!descriptor_.empty()) << *this; 808 CHECK(klass_.IsNull()) << *this; 809} 810 811void UnresolvedUninitializedRefType::CheckInvariants() const { 812 CHECK(!descriptor_.empty()) << *this; 813 CHECK(klass_.IsNull()) << *this; 814} 815 816UnresolvedMergedType::UnresolvedMergedType(const RegType& resolved, 817 const BitVector& unresolved, 818 const RegTypeCache* reg_type_cache, 819 uint16_t cache_id) 820 : UnresolvedType("", cache_id), 821 reg_type_cache_(reg_type_cache), 822 resolved_part_(resolved), 823 unresolved_types_(unresolved, false, unresolved.GetAllocator()) { 824 CheckConstructorInvariants(this); 825} 826void UnresolvedMergedType::CheckInvariants() const { 827 CHECK(reg_type_cache_ != nullptr); 828 829 // Unresolved merged types: merged types should be defined. 830 CHECK(descriptor_.empty()) << *this; 831 CHECK(klass_.IsNull()) << *this; 832 833 CHECK(!resolved_part_.IsConflict()); 834 CHECK(resolved_part_.IsReferenceTypes()); 835 CHECK(!resolved_part_.IsUnresolvedTypes()); 836 837 CHECK(resolved_part_.IsZero() || 838 !(resolved_part_.IsArrayTypes() && !resolved_part_.IsObjectArrayTypes())); 839 840 CHECK_GT(unresolved_types_.NumSetBits(), 0U); 841 bool unresolved_is_array = 842 reg_type_cache_->GetFromId(unresolved_types_.GetHighestBitSet()).IsArrayTypes(); 843 for (uint32_t idx : unresolved_types_.Indexes()) { 844 const RegType& t = reg_type_cache_->GetFromId(idx); 845 CHECK_EQ(unresolved_is_array, t.IsArrayTypes()); 846 } 847 848 if (!resolved_part_.IsZero()) { 849 CHECK_EQ(resolved_part_.IsArrayTypes(), unresolved_is_array); 850 } 851} 852 853bool UnresolvedMergedType::IsArrayTypes() const { 854 // For a merge to be an array, both the resolved and the unresolved part need to be object 855 // arrays. 856 // (Note: we encode a missing resolved part [which doesn't need to be an array] as zero.) 857 858 if (!resolved_part_.IsZero() && !resolved_part_.IsArrayTypes()) { 859 return false; 860 } 861 862 // It is enough to check just one of the merged types. Otherwise the merge should have been 863 // collapsed (checked in CheckInvariants on construction). 864 uint32_t idx = unresolved_types_.GetHighestBitSet(); 865 const RegType& unresolved = reg_type_cache_->GetFromId(idx); 866 return unresolved.IsArrayTypes(); 867} 868bool UnresolvedMergedType::IsObjectArrayTypes() const { 869 // Same as IsArrayTypes, as primitive arrays are always resolved. 870 return IsArrayTypes(); 871} 872 873void UnresolvedReferenceType::CheckInvariants() const { 874 CHECK(!descriptor_.empty()) << *this; 875 CHECK(klass_.IsNull()) << *this; 876} 877 878void UnresolvedSuperClass::CheckInvariants() const { 879 // Unresolved merged types: merged types should be defined. 880 CHECK(descriptor_.empty()) << *this; 881 CHECK(klass_.IsNull()) << *this; 882 CHECK_NE(unresolved_child_id_, 0U) << *this; 883} 884 885std::ostream& operator<<(std::ostream& os, const RegType& rhs) { 886 os << rhs.Dump(); 887 return os; 888} 889 890bool RegType::CanAssignArray(const RegType& src, 891 RegTypeCache& reg_types, 892 Handle<mirror::ClassLoader> class_loader, 893 MethodVerifier* verifier, 894 bool* soft_error) const { 895 if (!IsArrayTypes() || !src.IsArrayTypes()) { 896 *soft_error = false; 897 return false; 898 } 899 900 if (IsUnresolvedMergedReference() || src.IsUnresolvedMergedReference()) { 901 // An unresolved array type means that it's an array of some reference type. Reference arrays 902 // can never be assigned to primitive-type arrays, and vice versa. So it is a soft error if 903 // both arrays are reference arrays, otherwise a hard error. 904 *soft_error = IsObjectArrayTypes() && src.IsObjectArrayTypes(); 905 return false; 906 } 907 908 const RegType& cmp1 = reg_types.GetComponentType(*this, class_loader.Get()); 909 const RegType& cmp2 = reg_types.GetComponentType(src, class_loader.Get()); 910 911 if (cmp1.IsAssignableFrom(cmp2, verifier)) { 912 return true; 913 } 914 if (cmp1.IsUnresolvedTypes()) { 915 if (cmp2.IsIntegralTypes() || cmp2.IsFloatTypes() || cmp2.IsArrayTypes()) { 916 *soft_error = false; 917 return false; 918 } 919 *soft_error = true; 920 return false; 921 } 922 if (cmp2.IsUnresolvedTypes()) { 923 if (cmp1.IsIntegralTypes() || cmp1.IsFloatTypes() || cmp1.IsArrayTypes()) { 924 *soft_error = false; 925 return false; 926 } 927 *soft_error = true; 928 return false; 929 } 930 if (!cmp1.IsArrayTypes() || !cmp2.IsArrayTypes()) { 931 *soft_error = false; 932 return false; 933 } 934 return cmp1.CanAssignArray(cmp2, reg_types, class_loader, verifier, soft_error); 935} 936 937 938} // namespace verifier 939} // namespace art 940