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/*
* Copyright (C) 2016 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.
*/
/*
* Mterp entry point and support functions.
*/
#include "mterp.h"
#include "base/quasi_atomic.h"
#include "debugger.h"
#include "entrypoints/entrypoint_utils-inl.h"
#include "interpreter/interpreter_common.h"
#include "interpreter/interpreter_intrinsics.h"
#include "interpreter/shadow_frame-inl.h"
#include "mirror/string-alloc-inl.h"
namespace art {
namespace interpreter {
/*
* Verify some constants used by the mterp interpreter.
*/
void CheckMterpAsmConstants() {
/*
* If we're using computed goto instruction transitions, make sure
* none of the handlers overflows the byte limit. This won't tell
* which one did, but if any one is too big the total size will
* overflow.
*/
const int width = kMterpHandlerSize;
int interp_size = (uintptr_t) artMterpAsmInstructionEnd -
(uintptr_t) artMterpAsmInstructionStart;
if ((interp_size == 0) || (interp_size != (art::kNumPackedOpcodes * width))) {
LOG(FATAL) << "ERROR: unexpected asm interp size " << interp_size
<< "(did an instruction handler exceed " << width << " bytes?)";
}
}
void InitMterpTls(Thread* self) {
self->SetMterpCurrentIBase(artMterpAsmInstructionStart);
}
/*
* Find the matching case. Returns the offset to the handler instructions.
*
* Returns 3 if we don't find a match (it's the size of the sparse-switch
* instruction).
*/
extern "C" ssize_t MterpDoSparseSwitch(const uint16_t* switchData, int32_t testVal) {
const int kInstrLen = 3;
uint16_t size;
const int32_t* keys;
const int32_t* entries;
/*
* Sparse switch data format:
* ushort ident = 0x0200 magic value
* ushort size number of entries in the table; > 0
* int keys[size] keys, sorted low-to-high; 32-bit aligned
* int targets[size] branch targets, relative to switch opcode
*
* Total size is (2+size*4) 16-bit code units.
*/
uint16_t signature = *switchData++;
DCHECK_EQ(signature, static_cast<uint16_t>(art::Instruction::kSparseSwitchSignature));
size = *switchData++;
/* The keys are guaranteed to be aligned on a 32-bit boundary;
* we can treat them as a native int array.
*/
keys = reinterpret_cast<const int32_t*>(switchData);
/* The entries are guaranteed to be aligned on a 32-bit boundary;
* we can treat them as a native int array.
*/
entries = keys + size;
/*
* Binary-search through the array of keys, which are guaranteed to
* be sorted low-to-high.
*/
int lo = 0;
int hi = size - 1;
while (lo <= hi) {
int mid = (lo + hi) >> 1;
int32_t foundVal = keys[mid];
if (testVal < foundVal) {
hi = mid - 1;
} else if (testVal > foundVal) {
lo = mid + 1;
} else {
return entries[mid];
}
}
return kInstrLen;
}
extern "C" ssize_t MterpDoPackedSwitch(const uint16_t* switchData, int32_t testVal) {
const int kInstrLen = 3;
/*
* Packed switch data format:
* ushort ident = 0x0100 magic value
* ushort size number of entries in the table
* int first_key first (and lowest) switch case value
* int targets[size] branch targets, relative to switch opcode
*
* Total size is (4+size*2) 16-bit code units.
*/
uint16_t signature = *switchData++;
DCHECK_EQ(signature, static_cast<uint16_t>(art::Instruction::kPackedSwitchSignature));
uint16_t size = *switchData++;
int32_t firstKey = *switchData++;
firstKey |= (*switchData++) << 16;
int index = testVal - firstKey;
if (index < 0 || index >= size) {
return kInstrLen;
}
/*
* The entries are guaranteed to be aligned on a 32-bit boundary;
* we can treat them as a native int array.
*/
const int32_t* entries = reinterpret_cast<const int32_t*>(switchData);
return entries[index];
}
bool CanUseMterp()
REQUIRES_SHARED(Locks::mutator_lock_) {
const Runtime* const runtime = Runtime::Current();
return
!runtime->IsAotCompiler() &&
!runtime->GetInstrumentation()->IsActive() &&
// mterp only knows how to deal with the normal exits. It cannot handle any of the
// non-standard force-returns.
!runtime->AreNonStandardExitsEnabled() &&
// An async exception has been thrown. We need to go to the switch interpreter. MTerp doesn't
// know how to deal with these so we could end up never dealing with it if we are in an
// infinite loop.
!runtime->AreAsyncExceptionsThrown() &&
(runtime->GetJit() == nullptr || !runtime->GetJit()->JitAtFirstUse());
}
#define MTERP_INVOKE(Name) \
extern "C" size_t MterpInvoke##Name(Thread* self, \
ShadowFrame* shadow_frame, \
uint16_t* dex_pc_ptr, \
uint16_t inst_data) \
REQUIRES_SHARED(Locks::mutator_lock_) { \
JValue* result_register = shadow_frame->GetResultRegister(); \
const Instruction* inst = Instruction::At(dex_pc_ptr); \
if (shadow_frame->GetMethod()->SkipAccessChecks()) { \
return DoInvoke<k##Name, /*is_range=*/ false, /*do_access_check=*/ false, /*is_mterp=*/ true>( \
self, *shadow_frame, inst, inst_data, result_register) ? 1u : 0u; \
} else { \
return DoInvoke<k##Name, /*is_range=*/ false, /*do_access_check=*/ true, /*is_mterp=*/ true>( \
self, *shadow_frame, inst, inst_data, result_register) ? 1u : 0u; \
} \
} \
extern "C" size_t MterpInvoke##Name##Range(Thread* self, \
ShadowFrame* shadow_frame, \
uint16_t* dex_pc_ptr, \
uint16_t inst_data) \
REQUIRES_SHARED(Locks::mutator_lock_) { \
JValue* result_register = shadow_frame->GetResultRegister(); \
const Instruction* inst = Instruction::At(dex_pc_ptr); \
if (shadow_frame->GetMethod()->SkipAccessChecks()) { \
return DoInvoke<k##Name, /*is_range=*/ true, /*do_access_check=*/ false, /*is_mterp=*/ true>( \
self, *shadow_frame, inst, inst_data, result_register) ? 1u : 0u; \
} else { \
return DoInvoke<k##Name, /*is_range=*/ true, /*do_access_check=*/ true, /*is_mterp=*/ true>( \
self, *shadow_frame, inst, inst_data, result_register) ? 1u : 0u; \
} \
}
MTERP_INVOKE(Virtual)
MTERP_INVOKE(Super)
MTERP_INVOKE(Interface)
MTERP_INVOKE(Direct)
MTERP_INVOKE(Static)
#undef MTERP_INVOKE
extern "C" size_t MterpInvokeCustom(Thread* self,
ShadowFrame* shadow_frame,
uint16_t* dex_pc_ptr,
uint16_t inst_data)
REQUIRES_SHARED(Locks::mutator_lock_) {
JValue* result_register = shadow_frame->GetResultRegister();
const Instruction* inst = Instruction::At(dex_pc_ptr);
return DoInvokeCustom</* is_range= */ false>(
self, *shadow_frame, inst, inst_data, result_register) ? 1u : 0u;
}
extern "C" size_t MterpInvokePolymorphic(Thread* self,
ShadowFrame* shadow_frame,
uint16_t* dex_pc_ptr,
uint16_t inst_data)
REQUIRES_SHARED(Locks::mutator_lock_) {
JValue* result_register = shadow_frame->GetResultRegister();
const Instruction* inst = Instruction::At(dex_pc_ptr);
return DoInvokePolymorphic</* is_range= */ false>(
self, *shadow_frame, inst, inst_data, result_register) ? 1u : 0u;
}
extern "C" size_t MterpInvokeCustomRange(Thread* self,
ShadowFrame* shadow_frame,
uint16_t* dex_pc_ptr,
uint16_t inst_data)
REQUIRES_SHARED(Locks::mutator_lock_) {
JValue* result_register = shadow_frame->GetResultRegister();
const Instruction* inst = Instruction::At(dex_pc_ptr);
return DoInvokeCustom</*is_range=*/ true>(
self, *shadow_frame, inst, inst_data, result_register) ? 1u : 0u;
}
extern "C" size_t MterpInvokePolymorphicRange(Thread* self,
ShadowFrame* shadow_frame,
uint16_t* dex_pc_ptr,
uint16_t inst_data)
REQUIRES_SHARED(Locks::mutator_lock_) {
JValue* result_register = shadow_frame->GetResultRegister();
const Instruction* inst = Instruction::At(dex_pc_ptr);
return DoInvokePolymorphic</* is_range= */ true>(
self, *shadow_frame, inst, inst_data, result_register) ? 1u : 0u;
}
extern "C" void MterpThreadFenceForConstructor() {
QuasiAtomic::ThreadFenceForConstructor();
}
extern "C" size_t MterpConstString(uint32_t index,
uint32_t tgt_vreg,
ShadowFrame* shadow_frame,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::String> s = ResolveString(self, *shadow_frame, dex::StringIndex(index));
if (UNLIKELY(s == nullptr)) {
return 1u;
}
shadow_frame->SetVRegReference(tgt_vreg, s);
return 0u;
}
extern "C" size_t MterpConstClass(uint32_t index,
uint32_t tgt_vreg,
ShadowFrame* shadow_frame,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::Class> c =
ResolveVerifyAndClinit(dex::TypeIndex(index),
shadow_frame->GetMethod(),
self,
/* can_run_clinit= */ false,
!shadow_frame->GetMethod()->SkipAccessChecks());
if (UNLIKELY(c == nullptr)) {
return 1u;
}
shadow_frame->SetVRegReference(tgt_vreg, c);
return 0u;
}
extern "C" size_t MterpConstMethodHandle(uint32_t index,
uint32_t tgt_vreg,
ShadowFrame* shadow_frame,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::MethodHandle> mh = ResolveMethodHandle(self, index, shadow_frame->GetMethod());
if (UNLIKELY(mh == nullptr)) {
return 1u;
}
shadow_frame->SetVRegReference(tgt_vreg, mh);
return 0u;
}
extern "C" size_t MterpConstMethodType(uint32_t index,
uint32_t tgt_vreg,
ShadowFrame* shadow_frame,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::MethodType> mt =
ResolveMethodType(self, dex::ProtoIndex(index), shadow_frame->GetMethod());
if (UNLIKELY(mt == nullptr)) {
return 1u;
}
shadow_frame->SetVRegReference(tgt_vreg, mt);
return 0u;
}
extern "C" size_t MterpCheckCast(uint32_t index,
StackReference<mirror::Object>* vreg_addr,
art::ArtMethod* method,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::Class> c =
ResolveVerifyAndClinit(dex::TypeIndex(index),
method,
self,
/* can_run_clinit= */ false,
!method->SkipAccessChecks());
if (UNLIKELY(c == nullptr)) {
return 1u;
}
// Must load obj from vreg following ResolveVerifyAndClinit due to moving gc.
ObjPtr<mirror::Object> obj = vreg_addr->AsMirrorPtr();
if (UNLIKELY(obj != nullptr && !obj->InstanceOf(c))) {
ThrowClassCastException(c, obj->GetClass());
return 1u;
}
return 0u;
}
extern "C" size_t MterpInstanceOf(uint32_t index,
StackReference<mirror::Object>* vreg_addr,
art::ArtMethod* method,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::Class> c = ResolveVerifyAndClinit(dex::TypeIndex(index),
method,
self,
/* can_run_clinit= */ false,
!method->SkipAccessChecks());
if (UNLIKELY(c == nullptr)) {
return 0u; // Caller will check for pending exception. Return value unimportant.
}
// Must load obj from vreg following ResolveVerifyAndClinit due to moving gc.
ObjPtr<mirror::Object> obj = vreg_addr->AsMirrorPtr();
return (obj != nullptr) && obj->InstanceOf(c) ? 1u : 0u;
}
extern "C" size_t MterpFillArrayData(mirror::Object* obj,
const Instruction::ArrayDataPayload* payload)
REQUIRES_SHARED(Locks::mutator_lock_) {
return FillArrayData(obj, payload) ? 1u : 0u;
}
extern "C" size_t MterpNewInstance(ShadowFrame* shadow_frame, Thread* self, uint32_t inst_data)
REQUIRES_SHARED(Locks::mutator_lock_) {
const Instruction* inst = Instruction::At(shadow_frame->GetDexPCPtr());
ObjPtr<mirror::Object> obj = nullptr;
ObjPtr<mirror::Class> c =
ResolveVerifyAndClinit(dex::TypeIndex(inst->VRegB_21c()),
shadow_frame->GetMethod(),
self,
/* can_run_clinit= */ false,
!shadow_frame->GetMethod()->SkipAccessChecks());
if (LIKELY(c != nullptr)) {
if (UNLIKELY(c->IsStringClass())) {
gc::AllocatorType allocator_type = Runtime::Current()->GetHeap()->GetCurrentAllocator();
obj = mirror::String::AllocEmptyString(self, allocator_type);
} else {
obj = AllocObjectFromCode(c, self, Runtime::Current()->GetHeap()->GetCurrentAllocator());
}
}
if (UNLIKELY(obj == nullptr)) {
return 0u;
}
obj->GetClass()->AssertInitializedOrInitializingInThread(self);
shadow_frame->SetVRegReference(inst->VRegA_21c(inst_data), obj);
return 1u;
}
extern "C" size_t MterpAputObject(ShadowFrame* shadow_frame,
uint16_t* dex_pc_ptr,
uint32_t inst_data)
REQUIRES_SHARED(Locks::mutator_lock_) {
const Instruction* inst = Instruction::At(dex_pc_ptr);
ObjPtr<mirror::Object> a = shadow_frame->GetVRegReference(inst->VRegB_23x());
if (UNLIKELY(a == nullptr)) {
return 0u;
}
int32_t index = shadow_frame->GetVReg(inst->VRegC_23x());
ObjPtr<mirror::Object> val = shadow_frame->GetVRegReference(inst->VRegA_23x(inst_data));
ObjPtr<mirror::ObjectArray<mirror::Object>> array = a->AsObjectArray<mirror::Object>();
if (array->CheckIsValidIndex(index) && array->CheckAssignable(val)) {
array->SetWithoutChecks<false>(index, val);
return 1u;
}
return 0u;
}
extern "C" size_t MterpFilledNewArray(ShadowFrame* shadow_frame,
uint16_t* dex_pc_ptr,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
const Instruction* inst = Instruction::At(dex_pc_ptr);
JValue* result_register = shadow_frame->GetResultRegister();
bool res = false;
if (shadow_frame->GetMethod()->SkipAccessChecks()) {
res = DoFilledNewArray</*is_range=*/false,
/*do_access_check=*/false,
/*transaction_active=*/false>(inst,
*shadow_frame,
self,
result_register);
} else {
res = DoFilledNewArray</*is_range=*/false,
/*do_access_check=*/true,
/*transaction_active=*/false>(inst,
*shadow_frame,
self,
result_register);
}
return res ? 1u : 0u;
}
extern "C" size_t MterpFilledNewArrayRange(ShadowFrame* shadow_frame,
uint16_t* dex_pc_ptr,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
const Instruction* inst = Instruction::At(dex_pc_ptr);
JValue* result_register = shadow_frame->GetResultRegister();
bool res = false;
if (shadow_frame->GetMethod()->SkipAccessChecks()) {
res = DoFilledNewArray</*is_range=*/true,
/*do_access_check=*/false,
/*transaction_active=*/false>(inst,
*shadow_frame,
self,
result_register);
} else {
res = DoFilledNewArray</*is_range=*/true,
/*do_access_check=*/true,
/*transaction_active=*/false>(inst,
*shadow_frame,
self,
result_register);
}
return res ? 1u : 0u;
}
extern "C" size_t MterpNewArray(ShadowFrame* shadow_frame,
uint16_t* dex_pc_ptr,
uint32_t inst_data, Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
const Instruction* inst = Instruction::At(dex_pc_ptr);
int32_t length = shadow_frame->GetVReg(inst->VRegB_22c(inst_data));
gc::AllocatorType allocator = Runtime::Current()->GetHeap()->GetCurrentAllocator();
ObjPtr<mirror::Object> obj;
if (shadow_frame->GetMethod()->SkipAccessChecks()) {
obj = AllocArrayFromCode</*kAccessCheck=*/ false>(dex::TypeIndex(inst->VRegC_22c()),
length,
shadow_frame->GetMethod(),
self,
allocator);
} else {
obj = AllocArrayFromCode</*kAccessCheck=*/ true>(dex::TypeIndex(inst->VRegC_22c()),
length,
shadow_frame->GetMethod(),
self,
allocator);
}
if (UNLIKELY(obj == nullptr)) {
return 0u;
}
shadow_frame->SetVRegReference(inst->VRegA_22c(inst_data), obj);
return 1u;
}
extern "C" size_t MterpHandleException(Thread* self, ShadowFrame* shadow_frame)
REQUIRES_SHARED(Locks::mutator_lock_) {
DCHECK(self->IsExceptionPending());
const instrumentation::Instrumentation* const instrumentation =
Runtime::Current()->GetInstrumentation();
return MoveToExceptionHandler(self, *shadow_frame, instrumentation) ? 1u : 0u;
}
struct MterpCheckHelper {
DECLARE_RUNTIME_DEBUG_FLAG(kSlowMode);
};
DEFINE_RUNTIME_DEBUG_FLAG(MterpCheckHelper, kSlowMode);
extern "C" void MterpCheckBefore(Thread* self, ShadowFrame* shadow_frame, uint16_t* dex_pc_ptr)
REQUIRES_SHARED(Locks::mutator_lock_) {
// Check that we are using the right interpreter.
if (kIsDebugBuild && self->UseMterp() != CanUseMterp()) {
// The flag might be currently being updated on all threads. Retry with lock.
MutexLock tll_mu(self, *Locks::thread_list_lock_);
DCHECK_EQ(self->UseMterp(), CanUseMterp());
}
DCHECK(!Runtime::Current()->IsActiveTransaction());
const Instruction* inst = Instruction::At(dex_pc_ptr);
uint16_t inst_data = inst->Fetch16(0);
if (inst->Opcode(inst_data) == Instruction::MOVE_EXCEPTION) {
self->AssertPendingException();
} else {
self->AssertNoPendingException();
}
if (kTraceExecutionEnabled) {
uint32_t dex_pc = dex_pc_ptr - shadow_frame->GetDexInstructions();
TraceExecution(*shadow_frame, inst, dex_pc);
}
if (kTestExportPC) {
// Save invalid dex pc to force segfault if improperly used.
shadow_frame->SetDexPCPtr(reinterpret_cast<uint16_t*>(kExportPCPoison));
}
if (MterpCheckHelper::kSlowMode) {
shadow_frame->CheckConsistentVRegs();
}
}
extern "C" void MterpLogDivideByZeroException(Thread* self, ShadowFrame* shadow_frame)
REQUIRES_SHARED(Locks::mutator_lock_) {
UNUSED(self);
const Instruction* inst = Instruction::At(shadow_frame->GetDexPCPtr());
uint16_t inst_data = inst->Fetch16(0);
LOG(INFO) << "DivideByZero: " << inst->Opcode(inst_data);
}
extern "C" void MterpLogArrayIndexException(Thread* self, ShadowFrame* shadow_frame)
REQUIRES_SHARED(Locks::mutator_lock_) {
UNUSED(self);
const Instruction* inst = Instruction::At(shadow_frame->GetDexPCPtr());
uint16_t inst_data = inst->Fetch16(0);
LOG(INFO) << "ArrayIndex: " << inst->Opcode(inst_data);
}
extern "C" void MterpLogNegativeArraySizeException(Thread* self, ShadowFrame* shadow_frame)
REQUIRES_SHARED(Locks::mutator_lock_) {
UNUSED(self);
const Instruction* inst = Instruction::At(shadow_frame->GetDexPCPtr());
uint16_t inst_data = inst->Fetch16(0);
LOG(INFO) << "NegativeArraySize: " << inst->Opcode(inst_data);
}
extern "C" void MterpLogNoSuchMethodException(Thread* self, ShadowFrame* shadow_frame)
REQUIRES_SHARED(Locks::mutator_lock_) {
UNUSED(self);
const Instruction* inst = Instruction::At(shadow_frame->GetDexPCPtr());
uint16_t inst_data = inst->Fetch16(0);
LOG(INFO) << "NoSuchMethod: " << inst->Opcode(inst_data);
}
extern "C" void MterpLogExceptionThrownException(Thread* self, ShadowFrame* shadow_frame)
REQUIRES_SHARED(Locks::mutator_lock_) {
UNUSED(self);
const Instruction* inst = Instruction::At(shadow_frame->GetDexPCPtr());
uint16_t inst_data = inst->Fetch16(0);
LOG(INFO) << "ExceptionThrown: " << inst->Opcode(inst_data);
}
extern "C" void MterpLogNullObjectException(Thread* self, ShadowFrame* shadow_frame)
REQUIRES_SHARED(Locks::mutator_lock_) {
UNUSED(self);
const Instruction* inst = Instruction::At(shadow_frame->GetDexPCPtr());
uint16_t inst_data = inst->Fetch16(0);
LOG(INFO) << "NullObject: " << inst->Opcode(inst_data);
}
extern "C" void MterpLogFallback(Thread* self, ShadowFrame* shadow_frame)
REQUIRES_SHARED(Locks::mutator_lock_) {
UNUSED(self);
const Instruction* inst = Instruction::At(shadow_frame->GetDexPCPtr());
uint16_t inst_data = inst->Fetch16(0);
LOG(INFO) << "Fallback: " << inst->Opcode(inst_data) << ", Suspend Pending?: "
<< self->IsExceptionPending();
}
extern "C" void MterpLogOSR(Thread* self, ShadowFrame* shadow_frame, int32_t offset)
REQUIRES_SHARED(Locks::mutator_lock_) {
UNUSED(self);
const Instruction* inst = Instruction::At(shadow_frame->GetDexPCPtr());
uint16_t inst_data = inst->Fetch16(0);
LOG(INFO) << "OSR: " << inst->Opcode(inst_data) << ", offset = " << offset;
}
extern "C" void MterpLogSuspendFallback(Thread* self, ShadowFrame* shadow_frame, uint32_t flags)
REQUIRES_SHARED(Locks::mutator_lock_) {
UNUSED(self);
const Instruction* inst = Instruction::At(shadow_frame->GetDexPCPtr());
uint16_t inst_data = inst->Fetch16(0);
if (flags & kCheckpointRequest) {
LOG(INFO) << "Checkpoint fallback: " << inst->Opcode(inst_data);
} else if (flags & kSuspendRequest) {
LOG(INFO) << "Suspend fallback: " << inst->Opcode(inst_data);
} else if (flags & kEmptyCheckpointRequest) {
LOG(INFO) << "Empty checkpoint fallback: " << inst->Opcode(inst_data);
}
}
extern "C" size_t MterpSuspendCheck(Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
self->AllowThreadSuspension();
return !self->UseMterp();
}
// Execute single field access instruction (get/put, static/instance).
// The template arguments reduce this to fairly small amount of code.
// It requires the target object and field to be already resolved.
template<typename PrimType, FindFieldType kAccessType>
ALWAYS_INLINE void MterpFieldAccess(Instruction* inst,
uint16_t inst_data,
ShadowFrame* shadow_frame,
ObjPtr<mirror::Object> obj,
MemberOffset offset,
bool is_volatile)
REQUIRES_SHARED(Locks::mutator_lock_) {
static_assert(std::is_integral<PrimType>::value, "Unexpected primitive type");
constexpr bool kIsStatic = (kAccessType & FindFieldFlags::StaticBit) != 0;
constexpr bool kIsPrimitive = (kAccessType & FindFieldFlags::PrimitiveBit) != 0;
constexpr bool kIsRead = (kAccessType & FindFieldFlags::ReadBit) != 0;
uint16_t vRegA = kIsStatic ? inst->VRegA_21c(inst_data) : inst->VRegA_22c(inst_data);
if (kIsPrimitive) {
if (kIsRead) {
PrimType value = UNLIKELY(is_volatile)
? obj->GetFieldPrimitive<PrimType, /*kIsVolatile=*/ true>(offset)
: obj->GetFieldPrimitive<PrimType, /*kIsVolatile=*/ false>(offset);
if (sizeof(PrimType) == sizeof(uint64_t)) {
shadow_frame->SetVRegLong(vRegA, value); // Set two consecutive registers.
} else {
shadow_frame->SetVReg(vRegA, static_cast<int32_t>(value)); // Sign/zero extend.
}
} else { // Write.
uint64_t value = (sizeof(PrimType) == sizeof(uint64_t))
? shadow_frame->GetVRegLong(vRegA)
: shadow_frame->GetVReg(vRegA);
if (UNLIKELY(is_volatile)) {
obj->SetFieldPrimitive<PrimType, /*kIsVolatile=*/ true>(offset, value);
} else {
obj->SetFieldPrimitive<PrimType, /*kIsVolatile=*/ false>(offset, value);
}
}
} else { // Object.
if (kIsRead) {
ObjPtr<mirror::Object> value = UNLIKELY(is_volatile)
? obj->GetFieldObjectVolatile<mirror::Object>(offset)
: obj->GetFieldObject<mirror::Object>(offset);
shadow_frame->SetVRegReference(vRegA, value);
} else { // Write.
ObjPtr<mirror::Object> value = shadow_frame->GetVRegReference(vRegA);
if (UNLIKELY(is_volatile)) {
obj->SetFieldObjectVolatile</*kTransactionActive=*/ false>(offset, value);
} else {
obj->SetFieldObject</*kTransactionActive=*/ false>(offset, value);
}
}
}
}
template<typename PrimType, FindFieldType kAccessType, bool do_access_checks>
NO_INLINE bool MterpFieldAccessSlow(Instruction* inst,
uint16_t inst_data,
ShadowFrame* shadow_frame,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
constexpr bool kIsStatic = (kAccessType & FindFieldFlags::StaticBit) != 0;
constexpr bool kIsRead = (kAccessType & FindFieldFlags::ReadBit) != 0;
// Update the dex pc in shadow frame, just in case anything throws.
shadow_frame->SetDexPCPtr(reinterpret_cast<uint16_t*>(inst));
ArtMethod* referrer = shadow_frame->GetMethod();
uint32_t field_idx = kIsStatic ? inst->VRegB_21c() : inst->VRegC_22c();
ArtField* field = FindFieldFromCode<kAccessType, do_access_checks>(
field_idx, referrer, self, sizeof(PrimType));
if (UNLIKELY(field == nullptr)) {
DCHECK(self->IsExceptionPending());
return false;
}
constexpr bool kIsPrimitive = (kAccessType & FindFieldFlags::PrimitiveBit) != 0;
if (!kIsPrimitive && !kIsRead) {
uint16_t vRegA = kIsStatic ? inst->VRegA_21c(inst_data) : inst->VRegA_22c(inst_data);
ObjPtr<mirror::Object> value = shadow_frame->GetVRegReference(vRegA);
if (value != nullptr && field->ResolveType() == nullptr) {
DCHECK(self->IsExceptionPending());
return false;
}
}
ObjPtr<mirror::Object> obj = kIsStatic
? field->GetDeclaringClass().Ptr()
: shadow_frame->GetVRegReference(inst->VRegB_22c(inst_data));
if (UNLIKELY(obj == nullptr)) {
ThrowNullPointerExceptionForFieldAccess(field, kIsRead);
return false;
}
MterpFieldAccess<PrimType, kAccessType>(
inst, inst_data, shadow_frame, obj, field->GetOffset(), field->IsVolatile());
return true;
}
// This methods is called from assembly to handle field access instructions.
template<typename PrimType, FindFieldType kAccessType, bool do_access_checks>
ALWAYS_INLINE bool MterpFieldAccessFast(Instruction* inst,
uint16_t inst_data,
ShadowFrame* shadow_frame,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
constexpr bool kIsStatic = (kAccessType & FindFieldFlags::StaticBit) != 0;
// Try to find the field in small thread-local cache first.
InterpreterCache* tls_cache = self->GetInterpreterCache();
size_t tls_value;
if (LIKELY(tls_cache->Get(inst, &tls_value))) {
// The meaning of the cache value is opcode-specific.
// It is ArtFiled* for static fields and the raw offset for instance fields.
size_t offset = kIsStatic
? reinterpret_cast<ArtField*>(tls_value)->GetOffset().SizeValue()
: tls_value;
if (kIsDebugBuild) {
uint32_t field_idx = kIsStatic ? inst->VRegB_21c() : inst->VRegC_22c();
ArtField* field = FindFieldFromCode<kAccessType, do_access_checks>(
field_idx, shadow_frame->GetMethod(), self, sizeof(PrimType));
DCHECK_EQ(offset, field->GetOffset().SizeValue());
}
ObjPtr<mirror::Object> obj = kIsStatic
? reinterpret_cast<ArtField*>(tls_value)->GetDeclaringClass()
: ObjPtr<mirror::Object>(shadow_frame->GetVRegReference(inst->VRegB_22c(inst_data)));
if (LIKELY(obj != nullptr)) {
MterpFieldAccess<PrimType, kAccessType>(
inst, inst_data, shadow_frame, obj, MemberOffset(offset), /* is_volatile= */ false);
return true;
}
}
// This effectively inlines the fast path from ArtMethod::GetDexCache.
ArtMethod* referrer = shadow_frame->GetMethod();
if (LIKELY(!referrer->IsObsolete() && !do_access_checks)) {
// Avoid read barriers, since we need only the pointer to the native (non-movable)
// DexCache field array which we can get even through from-space objects.
ObjPtr<mirror::Class> klass = referrer->GetDeclaringClass<kWithoutReadBarrier>();
ObjPtr<mirror::DexCache> dex_cache =
klass->GetDexCache<kDefaultVerifyFlags, kWithoutReadBarrier>();
// Try to find the desired field in DexCache.
uint32_t field_idx = kIsStatic ? inst->VRegB_21c() : inst->VRegC_22c();
ArtField* field = dex_cache->GetResolvedField(field_idx);
if (LIKELY(field != nullptr)) {
bool visibly_initialized = !kIsStatic || field->GetDeclaringClass()->IsVisiblyInitialized();
if (LIKELY(visibly_initialized)) {
DCHECK_EQ(field, (FindFieldFromCode<kAccessType, do_access_checks>(
field_idx, referrer, self, sizeof(PrimType))));
ObjPtr<mirror::Object> obj = kIsStatic
? field->GetDeclaringClass().Ptr()
: shadow_frame->GetVRegReference(inst->VRegB_22c(inst_data));
// We check if nterp is supported as nterp and mterp use the cache in an
// incompatible way.
if (!IsNterpSupported() && LIKELY(kIsStatic || obj != nullptr)) {
// Only non-volatile fields are allowed in the thread-local cache.
if (LIKELY(!field->IsVolatile())) {
if (kIsStatic) {
tls_cache->Set(inst, reinterpret_cast<uintptr_t>(field));
} else {
tls_cache->Set(inst, field->GetOffset().SizeValue());
}
}
MterpFieldAccess<PrimType, kAccessType>(
inst, inst_data, shadow_frame, obj, field->GetOffset(), field->IsVolatile());
return true;
}
}
}
}
// Slow path. Last and with identical arguments so that it becomes single instruction tail call.
return MterpFieldAccessSlow<PrimType, kAccessType, do_access_checks>(
inst, inst_data, shadow_frame, self);
}
#define MTERP_FIELD_ACCESSOR(Name, PrimType, AccessType) \
extern "C" bool Name(Instruction* inst, uint16_t inst_data, ShadowFrame* sf, Thread* self) \
REQUIRES_SHARED(Locks::mutator_lock_) { \
if (sf->GetMethod()->SkipAccessChecks()) { \
return MterpFieldAccessFast<PrimType, AccessType, false>(inst, inst_data, sf, self); \
} else { \
return MterpFieldAccessFast<PrimType, AccessType, true>(inst, inst_data, sf, self); \
} \
}
#define MTERP_FIELD_ACCESSORS_FOR_TYPE(Sufix, PrimType, Kind) \
MTERP_FIELD_ACCESSOR(MterpIGet##Sufix, PrimType, Instance##Kind##Read) \
MTERP_FIELD_ACCESSOR(MterpIPut##Sufix, PrimType, Instance##Kind##Write) \
MTERP_FIELD_ACCESSOR(MterpSGet##Sufix, PrimType, Static##Kind##Read) \
MTERP_FIELD_ACCESSOR(MterpSPut##Sufix, PrimType, Static##Kind##Write)
MTERP_FIELD_ACCESSORS_FOR_TYPE(I8, int8_t, Primitive)
MTERP_FIELD_ACCESSORS_FOR_TYPE(U8, uint8_t, Primitive)
MTERP_FIELD_ACCESSORS_FOR_TYPE(I16, int16_t, Primitive)
MTERP_FIELD_ACCESSORS_FOR_TYPE(U16, uint16_t, Primitive)
MTERP_FIELD_ACCESSORS_FOR_TYPE(U32, uint32_t, Primitive)
MTERP_FIELD_ACCESSORS_FOR_TYPE(U64, uint64_t, Primitive)
MTERP_FIELD_ACCESSORS_FOR_TYPE(Obj, uint32_t, Object)
// Check that the primitive type for Obj variant above is correct.
// It really must be primitive type for the templates to compile.
// In the case of objects, it is only used to get the field size.
static_assert(kHeapReferenceSize == sizeof(uint32_t), "Unexpected kHeapReferenceSize");
#undef MTERP_FIELD_ACCESSORS_FOR_TYPE
#undef MTERP_FIELD_ACCESSOR
extern "C" mirror::Object* artAGetObjectFromMterp(mirror::Object* arr,
int32_t index)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (UNLIKELY(arr == nullptr)) {
ThrowNullPointerExceptionFromInterpreter();
return nullptr;
}
ObjPtr<mirror::ObjectArray<mirror::Object>> array = arr->AsObjectArray<mirror::Object>();
if (LIKELY(array->CheckIsValidIndex(index))) {
return array->GetWithoutChecks(index).Ptr();
} else {
return nullptr;
}
}
extern "C" mirror::Object* artIGetObjectFromMterp(mirror::Object* obj,
uint32_t field_offset)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (UNLIKELY(obj == nullptr)) {
ThrowNullPointerExceptionFromInterpreter();
return nullptr;
}
return obj->GetFieldObject<mirror::Object>(MemberOffset(field_offset));
}
/*
* Create a hotness_countdown based on the current method hotness_count and profiling
* mode. In short, determine how many hotness events we hit before reporting back
* to the full instrumentation via MterpAddHotnessBatch. Called once on entry to the method,
* and regenerated following batch updates.
*/
extern "C" ssize_t MterpSetUpHotnessCountdown(ArtMethod* method,
ShadowFrame* shadow_frame,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
uint16_t hotness_count = method->GetCounter();
int32_t countdown_value = jit::kJitHotnessDisabled;
jit::Jit* jit = Runtime::Current()->GetJit();
if (jit != nullptr) {
int32_t warm_threshold = jit->WarmMethodThreshold();
int32_t hot_threshold = jit->HotMethodThreshold();
int32_t osr_threshold = jit->OSRMethodThreshold();
if (hotness_count < warm_threshold) {
countdown_value = warm_threshold - hotness_count;
} else if (hotness_count < hot_threshold) {
countdown_value = hot_threshold - hotness_count;
} else if (hotness_count < osr_threshold) {
countdown_value = osr_threshold - hotness_count;
} else {
countdown_value = jit::kJitCheckForOSR;
}
if (jit::Jit::ShouldUsePriorityThreadWeight(self)) {
int32_t priority_thread_weight = jit->PriorityThreadWeight();
countdown_value = std::min(countdown_value, countdown_value / priority_thread_weight);
}
}
/*
* The actual hotness threshold may exceed the range of our int16_t countdown value. This is
* not a problem, though. We can just break it down into smaller chunks.
*/
countdown_value = std::min(countdown_value,
static_cast<int32_t>(std::numeric_limits<int16_t>::max()));
shadow_frame->SetCachedHotnessCountdown(countdown_value);
shadow_frame->SetHotnessCountdown(countdown_value);
return countdown_value;
}
/*
* Report a batch of hotness events to the instrumentation and then return the new
* countdown value to the next time we should report.
*/
extern "C" ssize_t MterpAddHotnessBatch(ArtMethod* method,
ShadowFrame* shadow_frame,
Thread* self)
REQUIRES_SHARED(Locks::mutator_lock_) {
jit::Jit* jit = Runtime::Current()->GetJit();
if (jit != nullptr) {
int16_t count = shadow_frame->GetCachedHotnessCountdown() - shadow_frame->GetHotnessCountdown();
jit->AddSamples(self, method, count, /*with_backedges=*/ true);
}
return MterpSetUpHotnessCountdown(method, shadow_frame, self);
}
extern "C" size_t MterpMaybeDoOnStackReplacement(Thread* self,
ShadowFrame* shadow_frame,
int32_t offset)
REQUIRES_SHARED(Locks::mutator_lock_) {
int16_t osr_countdown = shadow_frame->GetCachedHotnessCountdown() - 1;
bool did_osr = false;
/*
* To reduce the cost of polling the compiler to determine whether the requested OSR
* compilation has completed, only check every Nth time. NOTE: the "osr_countdown <= 0"
* condition is satisfied either by the decrement below or the initial setting of
* the cached countdown field to kJitCheckForOSR, which elsewhere is asserted to be -1.
*/
if (osr_countdown <= 0) {
ArtMethod* method = shadow_frame->GetMethod();
JValue* result = shadow_frame->GetResultRegister();
uint32_t dex_pc = shadow_frame->GetDexPC();
jit::Jit* jit = Runtime::Current()->GetJit();
osr_countdown = jit::Jit::kJitRecheckOSRThreshold;
if (offset <= 0) {
// Keep updating hotness in case a compilation request was dropped. Eventually it will retry.
jit->AddSamples(self, method, osr_countdown, /*with_backedges=*/ true);
}
did_osr = jit::Jit::MaybeDoOnStackReplacement(self, method, dex_pc, offset, result);
}
shadow_frame->SetCachedHotnessCountdown(osr_countdown);
return did_osr ? 1u : 0u;
}
} // namespace interpreter
} // namespace art