| /* |
| * Copyright (C) 2014 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "inline_method_analyser.h" |
| |
| #include "art_field-inl.h" |
| #include "art_method-inl.h" |
| #include "base/enums.h" |
| #include "class_linker-inl.h" |
| #include "dex/code_item_accessors-inl.h" |
| #include "dex/dex_file-inl.h" |
| #include "dex/dex_instruction-inl.h" |
| #include "dex/dex_instruction.h" |
| #include "dex/dex_instruction_utils.h" |
| #include "mirror/class-inl.h" |
| #include "mirror/dex_cache-inl.h" |
| |
| /* |
| * NOTE: This code is part of the quick compiler. It lives in the runtime |
| * only to allow the debugger to check whether a method has been inlined. |
| */ |
| |
| namespace art { |
| |
| namespace { // anonymous namespace |
| |
| // Helper class for matching a pattern. |
| class Matcher { |
| public: |
| // Match function type. |
| using MatchFn = bool(Matcher*); |
| |
| template <size_t size> |
| static bool Match(const CodeItemDataAccessor* code_item, MatchFn* const (&pattern)[size]); |
| |
| // Match and advance. |
| |
| static bool Mark(Matcher* matcher); |
| |
| template <bool (Matcher::*Fn)()> |
| static bool Required(Matcher* matcher); |
| |
| template <bool (Matcher::*Fn)()> |
| static bool Repeated(Matcher* matcher); // On match, returns to the mark. |
| |
| // Match an individual instruction. |
| |
| template <Instruction::Code opcode> bool Opcode(); |
| bool Const0(); |
| bool IPutOnThis(); |
| |
| private: |
| explicit Matcher(const CodeItemDataAccessor* code_item) |
| : code_item_(code_item), |
| instruction_(code_item->begin()) {} |
| |
| static bool DoMatch(const CodeItemDataAccessor* code_item, MatchFn* const* pattern, size_t size); |
| |
| const CodeItemDataAccessor* const code_item_; |
| DexInstructionIterator instruction_; |
| size_t pos_ = 0u; |
| size_t mark_ = 0u; |
| }; |
| |
| template <size_t size> |
| bool Matcher::Match(const CodeItemDataAccessor* code_item, MatchFn* const (&pattern)[size]) { |
| return DoMatch(code_item, pattern, size); |
| } |
| |
| bool Matcher::Mark(Matcher* matcher) { |
| matcher->pos_ += 1u; // Advance to the next match function before marking. |
| matcher->mark_ = matcher->pos_; |
| return true; |
| } |
| |
| template <bool (Matcher::*Fn)()> |
| bool Matcher::Required(Matcher* matcher) { |
| if (!(matcher->*Fn)()) { |
| return false; |
| } |
| matcher->pos_ += 1u; |
| ++matcher->instruction_; |
| return true; |
| } |
| |
| template <bool (Matcher::*Fn)()> |
| bool Matcher::Repeated(Matcher* matcher) { |
| if (!(matcher->*Fn)()) { |
| // Didn't match optional instruction, try the next match function. |
| matcher->pos_ += 1u; |
| return true; |
| } |
| matcher->pos_ = matcher->mark_; |
| ++matcher->instruction_; |
| return true; |
| } |
| |
| template <Instruction::Code opcode> |
| bool Matcher::Opcode() { |
| return instruction_->Opcode() == opcode; |
| } |
| |
| // Match const 0. |
| bool Matcher::Const0() { |
| return IsInstructionDirectConst(instruction_->Opcode()) && |
| (instruction_->Opcode() == Instruction::CONST_WIDE ? instruction_->VRegB_51l() == 0 |
| : instruction_->VRegB() == 0); |
| } |
| |
| bool Matcher::IPutOnThis() { |
| DCHECK_NE(code_item_->InsSize(), 0u); |
| return IsInstructionIPut(instruction_->Opcode()) && |
| instruction_->VRegB_22c() == code_item_->RegistersSize() - code_item_->InsSize(); |
| } |
| |
| bool Matcher::DoMatch(const CodeItemDataAccessor* code_item, MatchFn* const* pattern, size_t size) { |
| Matcher matcher(code_item); |
| while (matcher.pos_ != size) { |
| if (!pattern[matcher.pos_](&matcher)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| // Used for a single invoke in a constructor. In that situation, the method verifier makes |
| // sure we invoke a constructor either in the same class or superclass with at least "this". |
| ArtMethod* GetTargetConstructor(ArtMethod* method, const Instruction* invoke_direct) |
| REQUIRES_SHARED(Locks::mutator_lock_) { |
| DCHECK_EQ(invoke_direct->Opcode(), Instruction::INVOKE_DIRECT); |
| if (kIsDebugBuild) { |
| CodeItemDataAccessor accessor(method->DexInstructionData()); |
| DCHECK_EQ(invoke_direct->VRegC_35c(), |
| accessor.RegistersSize() - accessor.InsSize()); |
| } |
| uint32_t method_index = invoke_direct->VRegB_35c(); |
| ArtMethod* target_method = Runtime::Current()->GetClassLinker()->LookupResolvedMethod( |
| method_index, method->GetDexCache(), method->GetClassLoader()); |
| if (kIsDebugBuild && target_method != nullptr) { |
| CHECK(!target_method->IsStatic()); |
| CHECK(target_method->IsConstructor()); |
| CHECK(target_method->GetDeclaringClass() == method->GetDeclaringClass() || |
| target_method->GetDeclaringClass() == method->GetDeclaringClass()->GetSuperClass()); |
| } |
| return target_method; |
| } |
| |
| // Return the forwarded arguments and check that all remaining arguments are zero. |
| // If the check fails, return static_cast<size_t>(-1). |
| size_t CountForwardedConstructorArguments(const CodeItemDataAccessor* code_item, |
| const Instruction* invoke_direct, |
| uint16_t zero_vreg_mask) { |
| DCHECK_EQ(invoke_direct->Opcode(), Instruction::INVOKE_DIRECT); |
| size_t number_of_args = invoke_direct->VRegA_35c(); |
| DCHECK_NE(number_of_args, 0u); |
| uint32_t args[Instruction::kMaxVarArgRegs]; |
| invoke_direct->GetVarArgs(args); |
| uint16_t this_vreg = args[0]; |
| DCHECK_EQ(this_vreg, code_item->RegistersSize() - code_item->InsSize()); // Checked by verifier. |
| size_t forwarded = 1u; |
| while (forwarded < number_of_args && |
| args[forwarded] == this_vreg + forwarded && |
| (zero_vreg_mask & (1u << args[forwarded])) == 0) { |
| ++forwarded; |
| } |
| for (size_t i = forwarded; i != number_of_args; ++i) { |
| if ((zero_vreg_mask & (1u << args[i])) == 0) { |
| return static_cast<size_t>(-1); |
| } |
| } |
| return forwarded; |
| } |
| |
| uint16_t GetZeroVRegMask(const Instruction* const0) { |
| DCHECK(IsInstructionDirectConst(const0->Opcode())); |
| DCHECK((const0->Opcode() == Instruction::CONST_WIDE) ? const0->VRegB_51l() == 0u |
| : const0->VRegB() == 0); |
| uint16_t base_mask = IsInstructionConstWide(const0->Opcode()) ? 3u : 1u; |
| return base_mask << const0->VRegA(); |
| } |
| |
| // We limit the number of IPUTs storing parameters. There can be any number |
| // of IPUTs that store the value 0 as they are useless in a constructor as |
| // the object always starts zero-initialized. We also eliminate all but the |
| // last store to any field as they are not observable; not even if the field |
| // is volatile as no reference to the object can escape from a constructor |
| // with this pattern. |
| static constexpr size_t kMaxConstructorIPuts = 3u; |
| |
| struct ConstructorIPutData { |
| ConstructorIPutData() : field_index(DexFile::kDexNoIndex16), arg(0u) { } |
| |
| uint16_t field_index; |
| uint16_t arg; |
| }; |
| |
| bool RecordConstructorIPut(ArtMethod* method, |
| const Instruction* new_iput, |
| uint16_t this_vreg, |
| uint16_t zero_vreg_mask, |
| /*inout*/ ConstructorIPutData (&iputs)[kMaxConstructorIPuts]) |
| REQUIRES_SHARED(Locks::mutator_lock_) { |
| DCHECK(IsInstructionIPut(new_iput->Opcode())); |
| uint32_t field_index = new_iput->VRegC_22c(); |
| ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); |
| ArtField* field = class_linker->LookupResolvedField(field_index, method, /* is_static= */ false); |
| if (UNLIKELY(field == nullptr)) { |
| return false; |
| } |
| // Remove previous IPUT to the same field, if any. Different field indexes may refer |
| // to the same field, so we need to compare resolved fields from the dex cache. |
| for (size_t old_pos = 0; old_pos != arraysize(iputs); ++old_pos) { |
| if (iputs[old_pos].field_index == DexFile::kDexNoIndex16) { |
| break; |
| } |
| ArtField* f = class_linker->LookupResolvedField(iputs[old_pos].field_index, |
| method, |
| /* is_static= */ false); |
| DCHECK(f != nullptr); |
| if (f == field) { |
| auto back_it = std::copy(iputs + old_pos + 1, iputs + arraysize(iputs), iputs + old_pos); |
| *back_it = ConstructorIPutData(); |
| break; |
| } |
| } |
| // If the stored value isn't zero, record the IPUT. |
| if ((zero_vreg_mask & (1u << new_iput->VRegA_22c())) == 0u) { |
| size_t new_pos = 0; |
| while (new_pos != arraysize(iputs) && iputs[new_pos].field_index != DexFile::kDexNoIndex16) { |
| ++new_pos; |
| } |
| if (new_pos == arraysize(iputs)) { |
| return false; // Exceeded capacity of the output array. |
| } |
| iputs[new_pos].field_index = field_index; |
| iputs[new_pos].arg = new_iput->VRegA_22c() - this_vreg; |
| } |
| return true; |
| } |
| |
| bool DoAnalyseConstructor(const CodeItemDataAccessor* code_item, |
| ArtMethod* method, |
| /*inout*/ ConstructorIPutData (&iputs)[kMaxConstructorIPuts]) |
| REQUIRES_SHARED(Locks::mutator_lock_) { |
| // On entry we should not have any IPUTs yet. |
| DCHECK_EQ(0, std::count_if( |
| iputs, |
| iputs + arraysize(iputs), |
| [](const ConstructorIPutData& iput_data) { |
| return iput_data.field_index != DexFile::kDexNoIndex16; |
| })); |
| |
| // Limit the maximum number of code units we're willing to match. |
| static constexpr size_t kMaxCodeUnits = 16u; |
| |
| // Limit the number of registers that the constructor may use to 16. |
| // Given that IPUTs must use low 16 registers and we do not match MOVEs, |
| // this is a reasonable limitation. |
| static constexpr size_t kMaxVRegs = 16u; |
| |
| // We try to match a constructor that calls another constructor (either in |
| // superclass or in the same class) with the same parameters, or with some |
| // parameters truncated (allowed only for calls to superclass constructor) |
| // or with extra parameters with value 0 (with any type, including null). |
| // This call can be followed by optional IPUTs on "this" storing either one |
| // of the parameters or 0 and the code must then finish with RETURN_VOID. |
| // The called constructor must be either java.lang.Object.<init>() or it |
| // must also match the same pattern. |
| static Matcher::MatchFn* const kConstructorPattern[] = { |
| &Matcher::Mark, |
| &Matcher::Repeated<&Matcher::Const0>, |
| &Matcher::Required<&Matcher::Opcode<Instruction::INVOKE_DIRECT>>, |
| &Matcher::Mark, |
| &Matcher::Repeated<&Matcher::Const0>, |
| &Matcher::Repeated<&Matcher::IPutOnThis>, |
| &Matcher::Required<&Matcher::Opcode<Instruction::RETURN_VOID>>, |
| }; |
| |
| DCHECK(method != nullptr); |
| DCHECK(!method->IsStatic()); |
| DCHECK(method->IsConstructor()); |
| DCHECK(code_item != nullptr); |
| if (!method->GetDeclaringClass()->IsVerified() || |
| code_item->InsnsSizeInCodeUnits() > kMaxCodeUnits || |
| code_item->RegistersSize() > kMaxVRegs || |
| !Matcher::Match(code_item, kConstructorPattern)) { |
| return false; |
| } |
| |
| // Verify the invoke, prevent a few odd cases and collect IPUTs. |
| uint16_t this_vreg = code_item->RegistersSize() - code_item->InsSize(); |
| uint16_t zero_vreg_mask = 0u; |
| |
| for (const DexInstructionPcPair& pair : *code_item) { |
| const Instruction& instruction = pair.Inst(); |
| if (instruction.Opcode() == Instruction::RETURN_VOID) { |
| break; |
| } else if (instruction.Opcode() == Instruction::INVOKE_DIRECT) { |
| ArtMethod* target_method = GetTargetConstructor(method, &instruction); |
| if (target_method == nullptr) { |
| return false; |
| } |
| // We allow forwarding constructors only if they pass more arguments |
| // to prevent infinite recursion. |
| if (target_method->GetDeclaringClass() == method->GetDeclaringClass() && |
| instruction.VRegA_35c() <= code_item->InsSize()) { |
| return false; |
| } |
| size_t forwarded = CountForwardedConstructorArguments(code_item, &instruction, zero_vreg_mask); |
| if (forwarded == static_cast<size_t>(-1)) { |
| return false; |
| } |
| if (target_method->GetDeclaringClass()->IsObjectClass()) { |
| DCHECK_EQ(target_method->DexInstructionData().begin()->Opcode(), Instruction::RETURN_VOID); |
| } else { |
| CodeItemDataAccessor target_code_item(target_method->DexInstructionData()); |
| if (!target_code_item.HasCodeItem()) { |
| return false; // Native constructor? |
| } |
| if (!DoAnalyseConstructor(&target_code_item, target_method, iputs)) { |
| return false; |
| } |
| // Prune IPUTs with zero input. |
| auto kept_end = std::remove_if( |
| iputs, |
| iputs + arraysize(iputs), |
| [forwarded](const ConstructorIPutData& iput_data) { |
| return iput_data.arg >= forwarded; |
| }); |
| std::fill(kept_end, iputs + arraysize(iputs), ConstructorIPutData()); |
| // If we have any IPUTs from the call, check that the target method is in the same |
| // dex file (compare DexCache references), otherwise field_indexes would be bogus. |
| if (iputs[0].field_index != DexFile::kDexNoIndex16 && |
| target_method->GetDexCache() != method->GetDexCache()) { |
| return false; |
| } |
| } |
| } else if (IsInstructionDirectConst(instruction.Opcode())) { |
| zero_vreg_mask |= GetZeroVRegMask(&instruction); |
| if ((zero_vreg_mask & (1u << this_vreg)) != 0u) { |
| return false; // Overwriting `this` is unsupported. |
| } |
| } else { |
| DCHECK(IsInstructionIPut(instruction.Opcode())); |
| DCHECK_EQ(instruction.VRegB_22c(), this_vreg); |
| if (!RecordConstructorIPut(method, &instruction, this_vreg, zero_vreg_mask, iputs)) { |
| return false; |
| } |
| } |
| } |
| return true; |
| } |
| |
| } // anonymous namespace |
| |
| bool AnalyseConstructor(const CodeItemDataAccessor* code_item, |
| ArtMethod* method, |
| InlineMethod* result) |
| REQUIRES_SHARED(Locks::mutator_lock_) { |
| ConstructorIPutData iputs[kMaxConstructorIPuts]; |
| if (!DoAnalyseConstructor(code_item, method, iputs)) { |
| return false; |
| } |
| static_assert(kMaxConstructorIPuts == 3, "Unexpected limit"); // Code below depends on this. |
| DCHECK(iputs[0].field_index != DexFile::kDexNoIndex16 || |
| iputs[1].field_index == DexFile::kDexNoIndex16); |
| DCHECK(iputs[1].field_index != DexFile::kDexNoIndex16 || |
| iputs[2].field_index == DexFile::kDexNoIndex16); |
| |
| #define STORE_IPUT(n) \ |
| do { \ |
| result->d.constructor_data.iput##n##_field_index = iputs[n].field_index; \ |
| result->d.constructor_data.iput##n##_arg = iputs[n].arg; \ |
| } while (false) |
| |
| STORE_IPUT(0); |
| STORE_IPUT(1); |
| STORE_IPUT(2); |
| #undef STORE_IPUT |
| |
| result->opcode = kInlineOpConstructor; |
| result->d.constructor_data.reserved = 0u; |
| return true; |
| } |
| |
| static_assert(InlineMethodAnalyser::IsInstructionIGet(Instruction::IGET), "iget type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIGet(Instruction::IGET_WIDE), "iget_wide type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIGet(Instruction::IGET_OBJECT), |
| "iget_object type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIGet(Instruction::IGET_BOOLEAN), |
| "iget_boolean type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIGet(Instruction::IGET_BYTE), "iget_byte type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIGet(Instruction::IGET_CHAR), "iget_char type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIGet(Instruction::IGET_SHORT), "iget_short type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIPut(Instruction::IPUT), "iput type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIPut(Instruction::IPUT_WIDE), "iput_wide type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIPut(Instruction::IPUT_OBJECT), |
| "iput_object type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIPut(Instruction::IPUT_BOOLEAN), |
| "iput_boolean type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIPut(Instruction::IPUT_BYTE), "iput_byte type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIPut(Instruction::IPUT_CHAR), "iput_char type"); |
| static_assert(InlineMethodAnalyser::IsInstructionIPut(Instruction::IPUT_SHORT), "iput_short type"); |
| static_assert(InlineMethodAnalyser::IGetVariant(Instruction::IGET) == |
| InlineMethodAnalyser::IPutVariant(Instruction::IPUT), "iget/iput variant"); |
| static_assert(InlineMethodAnalyser::IGetVariant(Instruction::IGET_WIDE) == |
| InlineMethodAnalyser::IPutVariant(Instruction::IPUT_WIDE), "iget/iput_wide variant"); |
| static_assert(InlineMethodAnalyser::IGetVariant(Instruction::IGET_OBJECT) == |
| InlineMethodAnalyser::IPutVariant(Instruction::IPUT_OBJECT), "iget/iput_object variant"); |
| static_assert(InlineMethodAnalyser::IGetVariant(Instruction::IGET_BOOLEAN) == |
| InlineMethodAnalyser::IPutVariant(Instruction::IPUT_BOOLEAN), "iget/iput_boolean variant"); |
| static_assert(InlineMethodAnalyser::IGetVariant(Instruction::IGET_BYTE) == |
| InlineMethodAnalyser::IPutVariant(Instruction::IPUT_BYTE), "iget/iput_byte variant"); |
| static_assert(InlineMethodAnalyser::IGetVariant(Instruction::IGET_CHAR) == |
| InlineMethodAnalyser::IPutVariant(Instruction::IPUT_CHAR), "iget/iput_char variant"); |
| static_assert(InlineMethodAnalyser::IGetVariant(Instruction::IGET_SHORT) == |
| InlineMethodAnalyser::IPutVariant(Instruction::IPUT_SHORT), "iget/iput_short variant"); |
| |
| bool InlineMethodAnalyser::AnalyseMethodCode(ArtMethod* method, InlineMethod* result) { |
| CodeItemDataAccessor code_item(method->DexInstructionData()); |
| if (!code_item.HasCodeItem()) { |
| // Native or abstract. |
| return false; |
| } |
| return AnalyseMethodCode(&code_item, |
| MethodReference(method->GetDexFile(), method->GetDexMethodIndex()), |
| method->IsStatic(), |
| method, |
| result); |
| } |
| |
| bool InlineMethodAnalyser::AnalyseMethodCode(const CodeItemDataAccessor* code_item, |
| const MethodReference& method_ref, |
| bool is_static, |
| ArtMethod* method, |
| InlineMethod* result) { |
| // We currently support only plain return or 2-instruction methods. |
| |
| DCHECK_NE(code_item->InsnsSizeInCodeUnits(), 0u); |
| Instruction::Code opcode = code_item->begin()->Opcode(); |
| |
| switch (opcode) { |
| case Instruction::RETURN_VOID: |
| if (result != nullptr) { |
| result->opcode = kInlineOpNop; |
| result->d.data = 0u; |
| } |
| return true; |
| case Instruction::RETURN: |
| case Instruction::RETURN_OBJECT: |
| case Instruction::RETURN_WIDE: |
| return AnalyseReturnMethod(code_item, result); |
| case Instruction::CONST: |
| case Instruction::CONST_4: |
| case Instruction::CONST_16: |
| case Instruction::CONST_HIGH16: |
| // TODO: Support wide constants (RETURN_WIDE). |
| if (AnalyseConstMethod(code_item, result)) { |
| return true; |
| } |
| FALLTHROUGH_INTENDED; |
| case Instruction::CONST_WIDE: |
| case Instruction::CONST_WIDE_16: |
| case Instruction::CONST_WIDE_32: |
| case Instruction::CONST_WIDE_HIGH16: |
| case Instruction::INVOKE_DIRECT: |
| if (method != nullptr && !method->IsStatic() && method->IsConstructor()) { |
| return AnalyseConstructor(code_item, method, result); |
| } |
| return false; |
| case Instruction::IGET: |
| case Instruction::IGET_OBJECT: |
| case Instruction::IGET_BOOLEAN: |
| case Instruction::IGET_BYTE: |
| case Instruction::IGET_CHAR: |
| case Instruction::IGET_SHORT: |
| case Instruction::IGET_WIDE: |
| // TODO: Add handling for JIT. |
| // case Instruction::IGET_QUICK: |
| // case Instruction::IGET_WIDE_QUICK: |
| // case Instruction::IGET_OBJECT_QUICK: |
| return AnalyseIGetMethod(code_item, method_ref, is_static, method, result); |
| case Instruction::IPUT: |
| case Instruction::IPUT_OBJECT: |
| case Instruction::IPUT_BOOLEAN: |
| case Instruction::IPUT_BYTE: |
| case Instruction::IPUT_CHAR: |
| case Instruction::IPUT_SHORT: |
| case Instruction::IPUT_WIDE: |
| // TODO: Add handling for JIT. |
| // case Instruction::IPUT_QUICK: |
| // case Instruction::IPUT_WIDE_QUICK: |
| // case Instruction::IPUT_OBJECT_QUICK: |
| return AnalyseIPutMethod(code_item, method_ref, is_static, method, result); |
| default: |
| return false; |
| } |
| } |
| |
| bool InlineMethodAnalyser::IsSyntheticAccessor(MethodReference ref) { |
| const dex::MethodId& method_id = ref.dex_file->GetMethodId(ref.index); |
| const char* method_name = ref.dex_file->GetMethodName(method_id); |
| // javac names synthetic accessors "access$nnn", |
| // jack names them "-getN", "-putN", "-wrapN". |
| return strncmp(method_name, "access$", strlen("access$")) == 0 || |
| strncmp(method_name, "-", strlen("-")) == 0; |
| } |
| |
| bool InlineMethodAnalyser::AnalyseReturnMethod(const CodeItemDataAccessor* code_item, |
| InlineMethod* result) { |
| DexInstructionIterator return_instruction = code_item->begin(); |
| Instruction::Code return_opcode = return_instruction->Opcode(); |
| uint32_t reg = return_instruction->VRegA_11x(); |
| uint32_t arg_start = code_item->RegistersSize() - code_item->InsSize(); |
| DCHECK_GE(reg, arg_start); |
| DCHECK_LT((return_opcode == Instruction::RETURN_WIDE) ? reg + 1 : reg, |
| code_item->RegistersSize()); |
| |
| if (result != nullptr) { |
| result->opcode = kInlineOpReturnArg; |
| InlineReturnArgData* data = &result->d.return_data; |
| data->arg = reg - arg_start; |
| data->is_wide = (return_opcode == Instruction::RETURN_WIDE) ? 1u : 0u; |
| data->is_object = (return_opcode == Instruction::RETURN_OBJECT) ? 1u : 0u; |
| data->reserved = 0u; |
| data->reserved2 = 0u; |
| } |
| return true; |
| } |
| |
| bool InlineMethodAnalyser::AnalyseConstMethod(const CodeItemDataAccessor* code_item, |
| InlineMethod* result) { |
| DexInstructionIterator instruction = code_item->begin(); |
| const Instruction* return_instruction = instruction->Next(); |
| Instruction::Code return_opcode = return_instruction->Opcode(); |
| if (return_opcode != Instruction::RETURN && |
| return_opcode != Instruction::RETURN_OBJECT) { |
| return false; |
| } |
| |
| int32_t return_reg = return_instruction->VRegA_11x(); |
| DCHECK_LT(return_reg, code_item->RegistersSize()); |
| |
| int32_t const_value = instruction->VRegB(); |
| if (instruction->Opcode() == Instruction::CONST_HIGH16) { |
| const_value <<= 16; |
| } |
| DCHECK_LT(instruction->VRegA(), code_item->RegistersSize()); |
| if (instruction->VRegA() != return_reg) { |
| return false; // Not returning the value set by const? |
| } |
| if (return_opcode == Instruction::RETURN_OBJECT && const_value != 0) { |
| return false; // Returning non-null reference constant? |
| } |
| if (result != nullptr) { |
| result->opcode = kInlineOpNonWideConst; |
| result->d.data = static_cast<uint64_t>(const_value); |
| } |
| return true; |
| } |
| |
| bool InlineMethodAnalyser::AnalyseIGetMethod(const CodeItemDataAccessor* code_item, |
| const MethodReference& method_ref, |
| bool is_static, |
| ArtMethod* method, |
| InlineMethod* result) { |
| DexInstructionIterator instruction = code_item->begin(); |
| Instruction::Code opcode = instruction->Opcode(); |
| DCHECK(IsInstructionIGet(opcode)); |
| |
| const Instruction* return_instruction = instruction->Next(); |
| Instruction::Code return_opcode = return_instruction->Opcode(); |
| if (!(return_opcode == Instruction::RETURN_WIDE && opcode == Instruction::IGET_WIDE) && |
| !(return_opcode == Instruction::RETURN_OBJECT && opcode == Instruction::IGET_OBJECT) && |
| !(return_opcode == Instruction::RETURN && opcode != Instruction::IGET_WIDE && |
| opcode != Instruction::IGET_OBJECT)) { |
| return false; |
| } |
| |
| uint32_t return_reg = return_instruction->VRegA_11x(); |
| DCHECK_LT(return_opcode == Instruction::RETURN_WIDE ? return_reg + 1 : return_reg, |
| code_item->RegistersSize()); |
| |
| uint32_t dst_reg = instruction->VRegA_22c(); |
| uint32_t object_reg = instruction->VRegB_22c(); |
| uint32_t field_idx = instruction->VRegC_22c(); |
| uint32_t arg_start = code_item->RegistersSize() - code_item->InsSize(); |
| DCHECK_GE(object_reg, arg_start); |
| DCHECK_LT(object_reg, code_item->RegistersSize()); |
| uint32_t object_arg = object_reg - arg_start; |
| |
| DCHECK_LT(opcode == Instruction::IGET_WIDE ? dst_reg + 1 : dst_reg, code_item->RegistersSize()); |
| if (dst_reg != return_reg) { |
| return false; // Not returning the value retrieved by IGET? |
| } |
| |
| if (is_static || object_arg != 0u) { |
| // TODO: Implement inlining of IGET on non-"this" registers (needs correct stack trace for NPE). |
| // Allow synthetic accessors. We don't care about losing their stack frame in NPE. |
| if (!IsSyntheticAccessor(method_ref)) { |
| return false; |
| } |
| } |
| |
| // InlineIGetIPutData::object_arg is only 4 bits wide. |
| static constexpr uint16_t kMaxObjectArg = 15u; |
| if (object_arg > kMaxObjectArg) { |
| return false; |
| } |
| |
| if (result != nullptr) { |
| InlineIGetIPutData* data = &result->d.ifield_data; |
| if (!ComputeSpecialAccessorInfo(method, field_idx, false, data)) { |
| return false; |
| } |
| result->opcode = kInlineOpIGet; |
| data->op_variant = IGetVariant(opcode); |
| data->method_is_static = is_static ? 1u : 0u; |
| data->object_arg = object_arg; // Allow IGET on any register, not just "this". |
| data->src_arg = 0u; |
| data->return_arg_plus1 = 0u; |
| } |
| return true; |
| } |
| |
| bool InlineMethodAnalyser::AnalyseIPutMethod(const CodeItemDataAccessor* code_item, |
| const MethodReference& method_ref, |
| bool is_static, |
| ArtMethod* method, |
| InlineMethod* result) { |
| DexInstructionIterator instruction = code_item->begin(); |
| Instruction::Code opcode = instruction->Opcode(); |
| DCHECK(IsInstructionIPut(opcode)); |
| |
| const Instruction* return_instruction = instruction->Next(); |
| Instruction::Code return_opcode = return_instruction->Opcode(); |
| uint32_t arg_start = code_item->RegistersSize() - code_item->InsSize(); |
| uint16_t return_arg_plus1 = 0u; |
| if (return_opcode != Instruction::RETURN_VOID) { |
| if (return_opcode != Instruction::RETURN && |
| return_opcode != Instruction::RETURN_OBJECT && |
| return_opcode != Instruction::RETURN_WIDE) { |
| return false; |
| } |
| // Returning an argument. |
| uint32_t return_reg = return_instruction->VRegA_11x(); |
| DCHECK_GE(return_reg, arg_start); |
| DCHECK_LT(return_opcode == Instruction::RETURN_WIDE ? return_reg + 1u : return_reg, |
| code_item->RegistersSize()); |
| return_arg_plus1 = return_reg - arg_start + 1u; |
| } |
| |
| uint32_t src_reg = instruction->VRegA_22c(); |
| uint32_t object_reg = instruction->VRegB_22c(); |
| uint32_t field_idx = instruction->VRegC_22c(); |
| DCHECK_GE(object_reg, arg_start); |
| DCHECK_LT(object_reg, code_item->RegistersSize()); |
| DCHECK_GE(src_reg, arg_start); |
| DCHECK_LT(opcode == Instruction::IPUT_WIDE ? src_reg + 1 : src_reg, code_item->RegistersSize()); |
| uint32_t object_arg = object_reg - arg_start; |
| uint32_t src_arg = src_reg - arg_start; |
| |
| if (is_static || object_arg != 0u) { |
| // TODO: Implement inlining of IPUT on non-"this" registers (needs correct stack trace for NPE). |
| // Allow synthetic accessors. We don't care about losing their stack frame in NPE. |
| if (!IsSyntheticAccessor(method_ref)) { |
| return false; |
| } |
| } |
| |
| // InlineIGetIPutData::object_arg/src_arg/return_arg_plus1 are each only 4 bits wide. |
| static constexpr uint16_t kMaxObjectArg = 15u; |
| static constexpr uint16_t kMaxSrcArg = 15u; |
| static constexpr uint16_t kMaxReturnArgPlus1 = 15u; |
| if (object_arg > kMaxObjectArg || src_arg > kMaxSrcArg || return_arg_plus1 > kMaxReturnArgPlus1) { |
| return false; |
| } |
| |
| if (result != nullptr) { |
| InlineIGetIPutData* data = &result->d.ifield_data; |
| if (!ComputeSpecialAccessorInfo(method, field_idx, true, data)) { |
| return false; |
| } |
| result->opcode = kInlineOpIPut; |
| data->op_variant = IPutVariant(opcode); |
| data->method_is_static = is_static ? 1u : 0u; |
| data->object_arg = object_arg; // Allow IPUT on any register, not just "this". |
| data->src_arg = src_arg; |
| data->return_arg_plus1 = return_arg_plus1; |
| } |
| return true; |
| } |
| |
| bool InlineMethodAnalyser::ComputeSpecialAccessorInfo(ArtMethod* method, |
| uint32_t field_idx, |
| bool is_put, |
| InlineIGetIPutData* result) { |
| if (method == nullptr) { |
| return false; |
| } |
| ObjPtr<mirror::DexCache> dex_cache = method->GetDexCache(); |
| ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); |
| ArtField* field = class_linker->LookupResolvedField(field_idx, method, /* is_static= */ false); |
| if (field == nullptr || field->IsStatic()) { |
| return false; |
| } |
| ObjPtr<mirror::Class> method_class = method->GetDeclaringClass(); |
| ObjPtr<mirror::Class> field_class = field->GetDeclaringClass(); |
| if (!method_class->CanAccessResolvedField(field_class, field, dex_cache, field_idx) || |
| (is_put && field->IsFinal() && method_class != field_class)) { |
| return false; |
| } |
| DCHECK_GE(field->GetOffset().Int32Value(), 0); |
| // Historical note: We made sure not to interleave function calls with bit field writes to |
| // placate Valgrind. Bug: 27552451. |
| uint32_t field_offset = field->GetOffset().Uint32Value(); |
| bool is_volatile = field->IsVolatile(); |
| result->field_idx = field_idx; |
| result->field_offset = field_offset; |
| result->is_volatile = is_volatile ? 1u : 0u; |
| return true; |
| } |
| |
| } // namespace art |