/*
* Copyright (C) 2011 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 "stack.h"
#include "arch/context.h"
#include "art_method-inl.h"
#include "base/hex_dump.h"
#include "entrypoints/entrypoint_utils-inl.h"
#include "entrypoints/runtime_asm_entrypoints.h"
#include "gc/space/image_space.h"
#include "gc/space/space-inl.h"
#include "jit/jit.h"
#include "jit/jit_code_cache.h"
#include "linear_alloc.h"
#include "mirror/class-inl.h"
#include "mirror/object-inl.h"
#include "mirror/object_array-inl.h"
#include "oat_quick_method_header.h"
#include "quick/quick_method_frame_info.h"
#include "runtime.h"
#include "thread.h"
#include "thread_list.h"
#include "verify_object-inl.h"
namespace art {
static constexpr bool kDebugStackWalk = false;
mirror::Object* ShadowFrame::GetThisObject() const {
ArtMethod* m = GetMethod();
if (m->IsStatic()) {
return nullptr;
} else if (m->IsNative()) {
return GetVRegReference(0);
} else {
const DexFile::CodeItem* code_item = m->GetCodeItem();
CHECK(code_item != nullptr) << PrettyMethod(m);
uint16_t reg = code_item->registers_size_ - code_item->ins_size_;
return GetVRegReference(reg);
}
}
mirror::Object* ShadowFrame::GetThisObject(uint16_t num_ins) const {
ArtMethod* m = GetMethod();
if (m->IsStatic()) {
return nullptr;
} else {
return GetVRegReference(NumberOfVRegs() - num_ins);
}
}
size_t ManagedStack::NumJniShadowFrameReferences() const {
size_t count = 0;
for (const ManagedStack* current_fragment = this; current_fragment != nullptr;
current_fragment = current_fragment->GetLink()) {
for (ShadowFrame* current_frame = current_fragment->top_shadow_frame_; current_frame != nullptr;
current_frame = current_frame->GetLink()) {
if (current_frame->GetMethod()->IsNative()) {
// The JNI ShadowFrame only contains references. (For indirect reference.)
count += current_frame->NumberOfVRegs();
}
}
}
return count;
}
bool ManagedStack::ShadowFramesContain(StackReference<mirror::Object>* shadow_frame_entry) const {
for (const ManagedStack* current_fragment = this; current_fragment != nullptr;
current_fragment = current_fragment->GetLink()) {
for (ShadowFrame* current_frame = current_fragment->top_shadow_frame_; current_frame != nullptr;
current_frame = current_frame->GetLink()) {
if (current_frame->Contains(shadow_frame_entry)) {
return true;
}
}
}
return false;
}
StackVisitor::StackVisitor(Thread* thread, Context* context, StackWalkKind walk_kind)
: StackVisitor(thread, context, walk_kind, 0) {}
StackVisitor::StackVisitor(Thread* thread,
Context* context,
StackWalkKind walk_kind,
size_t num_frames)
: thread_(thread),
walk_kind_(walk_kind),
cur_shadow_frame_(nullptr),
cur_quick_frame_(nullptr),
cur_quick_frame_pc_(0),
cur_oat_quick_method_header_(nullptr),
num_frames_(num_frames),
cur_depth_(0),
current_inlining_depth_(0),
context_(context) {
DCHECK(thread == Thread::Current() || thread->IsSuspended()) << *thread;
}
InlineInfo StackVisitor::GetCurrentInlineInfo() const {
const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
uint32_t native_pc_offset = method_header->NativeQuickPcOffset(cur_quick_frame_pc_);
CodeInfo code_info = method_header->GetOptimizedCodeInfo();
CodeInfoEncoding encoding = code_info.ExtractEncoding();
StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset, encoding);
DCHECK(stack_map.IsValid());
return code_info.GetInlineInfoOf(stack_map, encoding);
}
ArtMethod* StackVisitor::GetMethod() const {
if (cur_shadow_frame_ != nullptr) {
return cur_shadow_frame_->GetMethod();
} else if (cur_quick_frame_ != nullptr) {
if (IsInInlinedFrame()) {
size_t depth_in_stack_map = current_inlining_depth_ - 1;
InlineInfo inline_info = GetCurrentInlineInfo();
const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
CodeInfoEncoding encoding = method_header->GetOptimizedCodeInfo().ExtractEncoding();
DCHECK(walk_kind_ != StackWalkKind::kSkipInlinedFrames);
bool allow_resolve = walk_kind_ != StackWalkKind::kIncludeInlinedFramesNoResolve;
return allow_resolve
? GetResolvedMethod<true>(*GetCurrentQuickFrame(),
inline_info,
encoding.inline_info_encoding,
depth_in_stack_map)
: GetResolvedMethod<false>(*GetCurrentQuickFrame(),
inline_info,
encoding.inline_info_encoding,
depth_in_stack_map);
} else {
return *cur_quick_frame_;
}
}
return nullptr;
}
uint32_t StackVisitor::GetDexPc(bool abort_on_failure) const {
if (cur_shadow_frame_ != nullptr) {
return cur_shadow_frame_->GetDexPC();
} else if (cur_quick_frame_ != nullptr) {
if (IsInInlinedFrame()) {
size_t depth_in_stack_map = current_inlining_depth_ - 1;
const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
CodeInfoEncoding encoding = method_header->GetOptimizedCodeInfo().ExtractEncoding();
return GetCurrentInlineInfo().GetDexPcAtDepth(encoding.inline_info_encoding,
depth_in_stack_map);
} else if (cur_oat_quick_method_header_ == nullptr) {
return DexFile::kDexNoIndex;
} else {
return cur_oat_quick_method_header_->ToDexPc(
GetMethod(), cur_quick_frame_pc_, abort_on_failure);
}
} else {
return 0;
}
}
extern "C" mirror::Object* artQuickGetProxyThisObject(ArtMethod** sp)
SHARED_REQUIRES(Locks::mutator_lock_);
mirror::Object* StackVisitor::GetThisObject() const {
DCHECK_EQ(Runtime::Current()->GetClassLinker()->GetImagePointerSize(), sizeof(void*));
ArtMethod* m = GetMethod();
if (m->IsStatic()) {
return nullptr;
} else if (m->IsNative()) {
if (cur_quick_frame_ != nullptr) {
HandleScope* hs = reinterpret_cast<HandleScope*>(
reinterpret_cast<char*>(cur_quick_frame_) + sizeof(ArtMethod*));
return hs->GetReference(0);
} else {
return cur_shadow_frame_->GetVRegReference(0);
}
} else if (m->IsProxyMethod()) {
if (cur_quick_frame_ != nullptr) {
return artQuickGetProxyThisObject(cur_quick_frame_);
} else {
return cur_shadow_frame_->GetVRegReference(0);
}
} else {
const DexFile::CodeItem* code_item = m->GetCodeItem();
if (code_item == nullptr) {
UNIMPLEMENTED(ERROR) << "Failed to determine this object of abstract or proxy method: "
<< PrettyMethod(m);
return nullptr;
} else {
uint16_t reg = code_item->registers_size_ - code_item->ins_size_;
uint32_t value = 0;
bool success = GetVReg(m, reg, kReferenceVReg, &value);
// We currently always guarantee the `this` object is live throughout the method.
CHECK(success) << "Failed to read the this object in " << PrettyMethod(m);
return reinterpret_cast<mirror::Object*>(value);
}
}
}
size_t StackVisitor::GetNativePcOffset() const {
DCHECK(!IsShadowFrame());
return GetCurrentOatQuickMethodHeader()->NativeQuickPcOffset(cur_quick_frame_pc_);
}
bool StackVisitor::GetVRegFromDebuggerShadowFrame(uint16_t vreg,
VRegKind kind,
uint32_t* val) const {
size_t frame_id = const_cast<StackVisitor*>(this)->GetFrameId();
ShadowFrame* shadow_frame = thread_->FindDebuggerShadowFrame(frame_id);
if (shadow_frame != nullptr) {
bool* updated_vreg_flags = thread_->GetUpdatedVRegFlags(frame_id);
DCHECK(updated_vreg_flags != nullptr);
if (updated_vreg_flags[vreg]) {
// Value is set by the debugger.
if (kind == kReferenceVReg) {
*val = static_cast<uint32_t>(reinterpret_cast<uintptr_t>(
shadow_frame->GetVRegReference(vreg)));
} else {
*val = shadow_frame->GetVReg(vreg);
}
return true;
}
}
// No value is set by the debugger.
return false;
}
bool StackVisitor::GetVReg(ArtMethod* m, uint16_t vreg, VRegKind kind, uint32_t* val) const {
if (cur_quick_frame_ != nullptr) {
DCHECK(context_ != nullptr); // You can't reliably read registers without a context.
DCHECK(m == GetMethod());
// Check if there is value set by the debugger.
if (GetVRegFromDebuggerShadowFrame(vreg, kind, val)) {
return true;
}
DCHECK(cur_oat_quick_method_header_->IsOptimized());
return GetVRegFromOptimizedCode(m, vreg, kind, val);
} else {
DCHECK(cur_shadow_frame_ != nullptr);
if (kind == kReferenceVReg) {
*val = static_cast<uint32_t>(reinterpret_cast<uintptr_t>(
cur_shadow_frame_->GetVRegReference(vreg)));
} else {
*val = cur_shadow_frame_->GetVReg(vreg);
}
return true;
}
}
bool StackVisitor::GetVRegFromOptimizedCode(ArtMethod* m, uint16_t vreg, VRegKind kind,
uint32_t* val) const {
DCHECK_EQ(m, GetMethod());
const DexFile::CodeItem* code_item = m->GetCodeItem();
DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be null or how would we compile
// its instructions?
uint16_t number_of_dex_registers = code_item->registers_size_;
DCHECK_LT(vreg, code_item->registers_size_);
const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
CodeInfo code_info = method_header->GetOptimizedCodeInfo();
CodeInfoEncoding encoding = code_info.ExtractEncoding();
uint32_t native_pc_offset = method_header->NativeQuickPcOffset(cur_quick_frame_pc_);
StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset, encoding);
DCHECK(stack_map.IsValid());
size_t depth_in_stack_map = current_inlining_depth_ - 1;
DexRegisterMap dex_register_map = IsInInlinedFrame()
? code_info.GetDexRegisterMapAtDepth(depth_in_stack_map,
code_info.GetInlineInfoOf(stack_map, encoding),
encoding,
number_of_dex_registers)
: code_info.GetDexRegisterMapOf(stack_map, encoding, number_of_dex_registers);
if (!dex_register_map.IsValid()) {
return false;
}
DexRegisterLocation::Kind location_kind =
dex_register_map.GetLocationKind(vreg, number_of_dex_registers, code_info, encoding);
switch (location_kind) {
case DexRegisterLocation::Kind::kInStack: {
const int32_t offset = dex_register_map.GetStackOffsetInBytes(vreg,
number_of_dex_registers,
code_info,
encoding);
const uint8_t* addr = reinterpret_cast<const uint8_t*>(cur_quick_frame_) + offset;
*val = *reinterpret_cast<const uint32_t*>(addr);
return true;
}
case DexRegisterLocation::Kind::kInRegister:
case DexRegisterLocation::Kind::kInRegisterHigh:
case DexRegisterLocation::Kind::kInFpuRegister:
case DexRegisterLocation::Kind::kInFpuRegisterHigh: {
uint32_t reg =
dex_register_map.GetMachineRegister(vreg, number_of_dex_registers, code_info, encoding);
return GetRegisterIfAccessible(reg, kind, val);
}
case DexRegisterLocation::Kind::kConstant:
*val = dex_register_map.GetConstant(vreg, number_of_dex_registers, code_info, encoding);
return true;
case DexRegisterLocation::Kind::kNone:
return false;
default:
LOG(FATAL)
<< "Unexpected location kind "
<< dex_register_map.GetLocationInternalKind(vreg,
number_of_dex_registers,
code_info,
encoding);
UNREACHABLE();
}
}
bool StackVisitor::GetRegisterIfAccessible(uint32_t reg, VRegKind kind, uint32_t* val) const {
const bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
// X86 float registers are 64-bit and the logic below does not apply.
DCHECK(!is_float || kRuntimeISA != InstructionSet::kX86);
if (!IsAccessibleRegister(reg, is_float)) {
return false;
}
uintptr_t ptr_val = GetRegister(reg, is_float);
const bool target64 = Is64BitInstructionSet(kRuntimeISA);
if (target64) {
const bool wide_lo = (kind == kLongLoVReg) || (kind == kDoubleLoVReg);
const bool wide_hi = (kind == kLongHiVReg) || (kind == kDoubleHiVReg);
int64_t value_long = static_cast<int64_t>(ptr_val);
if (wide_lo) {
ptr_val = static_cast<uintptr_t>(Low32Bits(value_long));
} else if (wide_hi) {
ptr_val = static_cast<uintptr_t>(High32Bits(value_long));
}
}
*val = ptr_val;
return true;
}
bool StackVisitor::GetVRegPairFromDebuggerShadowFrame(uint16_t vreg,
VRegKind kind_lo,
VRegKind kind_hi,
uint64_t* val) const {
uint32_t low_32bits;
uint32_t high_32bits;
bool success = GetVRegFromDebuggerShadowFrame(vreg, kind_lo, &low_32bits);
success &= GetVRegFromDebuggerShadowFrame(vreg + 1, kind_hi, &high_32bits);
if (success) {
*val = (static_cast<uint64_t>(high_32bits) << 32) | static_cast<uint64_t>(low_32bits);
}
return success;
}
bool StackVisitor::GetVRegPair(ArtMethod* m, uint16_t vreg, VRegKind kind_lo,
VRegKind kind_hi, uint64_t* val) const {
if (kind_lo == kLongLoVReg) {
DCHECK_EQ(kind_hi, kLongHiVReg);
} else if (kind_lo == kDoubleLoVReg) {
DCHECK_EQ(kind_hi, kDoubleHiVReg);
} else {
LOG(FATAL) << "Expected long or double: kind_lo=" << kind_lo << ", kind_hi=" << kind_hi;
UNREACHABLE();
}
// Check if there is value set by the debugger.
if (GetVRegPairFromDebuggerShadowFrame(vreg, kind_lo, kind_hi, val)) {
return true;
}
if (cur_quick_frame_ != nullptr) {
DCHECK(context_ != nullptr); // You can't reliably read registers without a context.
DCHECK(m == GetMethod());
DCHECK(cur_oat_quick_method_header_->IsOptimized());
return GetVRegPairFromOptimizedCode(m, vreg, kind_lo, kind_hi, val);
} else {
DCHECK(cur_shadow_frame_ != nullptr);
*val = cur_shadow_frame_->GetVRegLong(vreg);
return true;
}
}
bool StackVisitor::GetVRegPairFromOptimizedCode(ArtMethod* m, uint16_t vreg,
VRegKind kind_lo, VRegKind kind_hi,
uint64_t* val) const {
uint32_t low_32bits;
uint32_t high_32bits;
bool success = GetVRegFromOptimizedCode(m, vreg, kind_lo, &low_32bits);
success &= GetVRegFromOptimizedCode(m, vreg + 1, kind_hi, &high_32bits);
if (success) {
*val = (static_cast<uint64_t>(high_32bits) << 32) | static_cast<uint64_t>(low_32bits);
}
return success;
}
bool StackVisitor::GetRegisterPairIfAccessible(uint32_t reg_lo, uint32_t reg_hi,
VRegKind kind_lo, uint64_t* val) const {
const bool is_float = (kind_lo == kDoubleLoVReg);
if (!IsAccessibleRegister(reg_lo, is_float) || !IsAccessibleRegister(reg_hi, is_float)) {
return false;
}
uintptr_t ptr_val_lo = GetRegister(reg_lo, is_float);
uintptr_t ptr_val_hi = GetRegister(reg_hi, is_float);
bool target64 = Is64BitInstructionSet(kRuntimeISA);
if (target64) {
int64_t value_long_lo = static_cast<int64_t>(ptr_val_lo);
int64_t value_long_hi = static_cast<int64_t>(ptr_val_hi);
ptr_val_lo = static_cast<uintptr_t>(Low32Bits(value_long_lo));
ptr_val_hi = static_cast<uintptr_t>(High32Bits(value_long_hi));
}
*val = (static_cast<uint64_t>(ptr_val_hi) << 32) | static_cast<uint32_t>(ptr_val_lo);
return true;
}
bool StackVisitor::SetVReg(ArtMethod* m,
uint16_t vreg,
uint32_t new_value,
VRegKind kind) {
const DexFile::CodeItem* code_item = m->GetCodeItem();
if (code_item == nullptr) {
return false;
}
ShadowFrame* shadow_frame = GetCurrentShadowFrame();
if (shadow_frame == nullptr) {
// This is a compiled frame: we must prepare and update a shadow frame that will
// be executed by the interpreter after deoptimization of the stack.
const size_t frame_id = GetFrameId();
const uint16_t num_regs = code_item->registers_size_;
shadow_frame = thread_->FindOrCreateDebuggerShadowFrame(frame_id, num_regs, m, GetDexPc());
CHECK(shadow_frame != nullptr);
// Remember the vreg has been set for debugging and must not be overwritten by the
// original value during deoptimization of the stack.
thread_->GetUpdatedVRegFlags(frame_id)[vreg] = true;
}
if (kind == kReferenceVReg) {
shadow_frame->SetVRegReference(vreg, reinterpret_cast<mirror::Object*>(new_value));
} else {
shadow_frame->SetVReg(vreg, new_value);
}
return true;
}
bool StackVisitor::SetVRegPair(ArtMethod* m,
uint16_t vreg,
uint64_t new_value,
VRegKind kind_lo,
VRegKind kind_hi) {
if (kind_lo == kLongLoVReg) {
DCHECK_EQ(kind_hi, kLongHiVReg);
} else if (kind_lo == kDoubleLoVReg) {
DCHECK_EQ(kind_hi, kDoubleHiVReg);
} else {
LOG(FATAL) << "Expected long or double: kind_lo=" << kind_lo << ", kind_hi=" << kind_hi;
UNREACHABLE();
}
const DexFile::CodeItem* code_item = m->GetCodeItem();
if (code_item == nullptr) {
return false;
}
ShadowFrame* shadow_frame = GetCurrentShadowFrame();
if (shadow_frame == nullptr) {
// This is a compiled frame: we must prepare for deoptimization (see SetVRegFromDebugger).
const size_t frame_id = GetFrameId();
const uint16_t num_regs = code_item->registers_size_;
shadow_frame = thread_->FindOrCreateDebuggerShadowFrame(frame_id, num_regs, m, GetDexPc());
CHECK(shadow_frame != nullptr);
// Remember the vreg pair has been set for debugging and must not be overwritten by the
// original value during deoptimization of the stack.
thread_->GetUpdatedVRegFlags(frame_id)[vreg] = true;
thread_->GetUpdatedVRegFlags(frame_id)[vreg + 1] = true;
}
shadow_frame->SetVRegLong(vreg, new_value);
return true;
}
bool StackVisitor::IsAccessibleGPR(uint32_t reg) const {
DCHECK(context_ != nullptr);
return context_->IsAccessibleGPR(reg);
}
uintptr_t* StackVisitor::GetGPRAddress(uint32_t reg) const {
DCHECK(cur_quick_frame_ != nullptr) << "This is a quick frame routine";
DCHECK(context_ != nullptr);
return context_->GetGPRAddress(reg);
}
uintptr_t StackVisitor::GetGPR(uint32_t reg) const {
DCHECK(cur_quick_frame_ != nullptr) << "This is a quick frame routine";
DCHECK(context_ != nullptr);
return context_->GetGPR(reg);
}
bool StackVisitor::IsAccessibleFPR(uint32_t reg) const {
DCHECK(context_ != nullptr);
return context_->IsAccessibleFPR(reg);
}
uintptr_t StackVisitor::GetFPR(uint32_t reg) const {
DCHECK(cur_quick_frame_ != nullptr) << "This is a quick frame routine";
DCHECK(context_ != nullptr);
return context_->GetFPR(reg);
}
uintptr_t StackVisitor::GetReturnPc() const {
uint8_t* sp = reinterpret_cast<uint8_t*>(GetCurrentQuickFrame());
DCHECK(sp != nullptr);
uint8_t* pc_addr = sp + GetCurrentQuickFrameInfo().GetReturnPcOffset();
return *reinterpret_cast<uintptr_t*>(pc_addr);
}
void StackVisitor::SetReturnPc(uintptr_t new_ret_pc) {
uint8_t* sp = reinterpret_cast<uint8_t*>(GetCurrentQuickFrame());
CHECK(sp != nullptr);
uint8_t* pc_addr = sp + GetCurrentQuickFrameInfo().GetReturnPcOffset();
*reinterpret_cast<uintptr_t*>(pc_addr) = new_ret_pc;
}
size_t StackVisitor::ComputeNumFrames(Thread* thread, StackWalkKind walk_kind) {
struct NumFramesVisitor : public StackVisitor {
NumFramesVisitor(Thread* thread_in, StackWalkKind walk_kind_in)
: StackVisitor(thread_in, nullptr, walk_kind_in), frames(0) {}
bool VisitFrame() OVERRIDE {
frames++;
return true;
}
size_t frames;
};
NumFramesVisitor visitor(thread, walk_kind);
visitor.WalkStack(true);
return visitor.frames;
}
bool StackVisitor::GetNextMethodAndDexPc(ArtMethod** next_method, uint32_t* next_dex_pc) {
struct HasMoreFramesVisitor : public StackVisitor {
HasMoreFramesVisitor(Thread* thread,
StackWalkKind walk_kind,
size_t num_frames,
size_t frame_height)
: StackVisitor(thread, nullptr, walk_kind, num_frames),
frame_height_(frame_height),
found_frame_(false),
has_more_frames_(false),
next_method_(nullptr),
next_dex_pc_(0) {
}
bool VisitFrame() OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
if (found_frame_) {
ArtMethod* method = GetMethod();
if (method != nullptr && !method->IsRuntimeMethod()) {
has_more_frames_ = true;
next_method_ = method;
next_dex_pc_ = GetDexPc();
return false; // End stack walk once next method is found.
}
} else if (GetFrameHeight() == frame_height_) {
found_frame_ = true;
}
return true;
}
size_t frame_height_;
bool found_frame_;
bool has_more_frames_;
ArtMethod* next_method_;
uint32_t next_dex_pc_;
};
HasMoreFramesVisitor visitor(thread_, walk_kind_, GetNumFrames(), GetFrameHeight());
visitor.WalkStack(true);
*next_method = visitor.next_method_;
*next_dex_pc = visitor.next_dex_pc_;
return visitor.has_more_frames_;
}
void StackVisitor::DescribeStack(Thread* thread) {
struct DescribeStackVisitor : public StackVisitor {
explicit DescribeStackVisitor(Thread* thread_in)
: StackVisitor(thread_in, nullptr, StackVisitor::StackWalkKind::kIncludeInlinedFrames) {}
bool VisitFrame() OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
LOG(INFO) << "Frame Id=" << GetFrameId() << " " << DescribeLocation();
return true;
}
};
DescribeStackVisitor visitor(thread);
visitor.WalkStack(true);
}
std::string StackVisitor::DescribeLocation() const {
std::string result("Visiting method '");
ArtMethod* m = GetMethod();
if (m == nullptr) {
return "upcall";
}
result += PrettyMethod(m);
result += StringPrintf("' at dex PC 0x%04x", GetDexPc());
if (!IsShadowFrame()) {
result += StringPrintf(" (native PC %p)", reinterpret_cast<void*>(GetCurrentQuickFramePc()));
}
return result;
}
static instrumentation::InstrumentationStackFrame& GetInstrumentationStackFrame(Thread* thread,
uint32_t depth) {
CHECK_LT(depth, thread->GetInstrumentationStack()->size());
return thread->GetInstrumentationStack()->at(depth);
}
static void AssertPcIsWithinQuickCode(ArtMethod* method, uintptr_t pc)
SHARED_REQUIRES(Locks::mutator_lock_) {
if (method->IsNative() || method->IsRuntimeMethod() || method->IsProxyMethod()) {
return;
}
if (pc == reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc())) {
return;
}
const void* code = method->GetEntryPointFromQuickCompiledCode();
if (code == GetQuickInstrumentationEntryPoint()) {
return;
}
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
if (class_linker->IsQuickToInterpreterBridge(code) ||
class_linker->IsQuickResolutionStub(code)) {
return;
}
// If we are the JIT then we may have just compiled the method after the
// IsQuickToInterpreterBridge check.
Runtime* runtime = Runtime::Current();
if (runtime->UseJitCompilation() && runtime->GetJit()->GetCodeCache()->ContainsPc(code)) {
return;
}
uint32_t code_size = OatQuickMethodHeader::FromEntryPoint(code)->code_size_;
uintptr_t code_start = reinterpret_cast<uintptr_t>(code);
CHECK(code_start <= pc && pc <= (code_start + code_size))
<< PrettyMethod(method)
<< " pc=" << std::hex << pc
<< " code_start=" << code_start
<< " code_size=" << code_size;
}
void StackVisitor::SanityCheckFrame() const {
if (kIsDebugBuild) {
ArtMethod* method = GetMethod();
auto* declaring_class = method->GetDeclaringClass();
// Runtime methods have null declaring class.
if (!method->IsRuntimeMethod()) {
CHECK(declaring_class != nullptr);
CHECK_EQ(declaring_class->GetClass(), declaring_class->GetClass()->GetClass())
<< declaring_class;
} else {
CHECK(declaring_class == nullptr);
}
Runtime* const runtime = Runtime::Current();
LinearAlloc* const linear_alloc = runtime->GetLinearAlloc();
if (!linear_alloc->Contains(method)) {
// Check class linker linear allocs.
mirror::Class* klass = method->GetDeclaringClass();
LinearAlloc* const class_linear_alloc = (klass != nullptr)
? runtime->GetClassLinker()->GetAllocatorForClassLoader(klass->GetClassLoader())
: linear_alloc;
if (!class_linear_alloc->Contains(method)) {
// Check image space.
bool in_image = false;
for (auto& space : runtime->GetHeap()->GetContinuousSpaces()) {
if (space->IsImageSpace()) {
auto* image_space = space->AsImageSpace();
const auto& header = image_space->GetImageHeader();
const ImageSection& methods = header.GetMethodsSection();
const ImageSection& runtime_methods = header.GetRuntimeMethodsSection();
const size_t offset = reinterpret_cast<const uint8_t*>(method) - image_space->Begin();
if (methods.Contains(offset) || runtime_methods.Contains(offset)) {
in_image = true;
break;
}
}
}
CHECK(in_image) << PrettyMethod(method) << " not in linear alloc or image";
}
}
if (cur_quick_frame_ != nullptr) {
AssertPcIsWithinQuickCode(method, cur_quick_frame_pc_);
// Frame sanity.
size_t frame_size = GetCurrentQuickFrameInfo().FrameSizeInBytes();
CHECK_NE(frame_size, 0u);
// A rough guess at an upper size we expect to see for a frame.
// 256 registers
// 2 words HandleScope overhead
// 3+3 register spills
// TODO: this seems architecture specific for the case of JNI frames.
// TODO: 083-compiler-regressions ManyFloatArgs shows this estimate is wrong.
// const size_t kMaxExpectedFrameSize = (256 + 2 + 3 + 3) * sizeof(word);
const size_t kMaxExpectedFrameSize = 2 * KB;
CHECK_LE(frame_size, kMaxExpectedFrameSize) << PrettyMethod(method);
size_t return_pc_offset = GetCurrentQuickFrameInfo().GetReturnPcOffset();
CHECK_LT(return_pc_offset, frame_size);
}
}
}
// Counts the number of references in the parameter list of the corresponding method.
// Note: Thus does _not_ include "this" for non-static methods.
static uint32_t GetNumberOfReferenceArgsWithoutReceiver(ArtMethod* method)
SHARED_REQUIRES(Locks::mutator_lock_) {
uint32_t shorty_len;
const char* shorty = method->GetShorty(&shorty_len);
uint32_t refs = 0;
for (uint32_t i = 1; i < shorty_len ; ++i) {
if (shorty[i] == 'L') {
refs++;
}
}
return refs;
}
QuickMethodFrameInfo StackVisitor::GetCurrentQuickFrameInfo() const {
if (cur_oat_quick_method_header_ != nullptr) {
return cur_oat_quick_method_header_->GetFrameInfo();
}
ArtMethod* method = GetMethod();
Runtime* runtime = Runtime::Current();
if (method->IsAbstract()) {
return runtime->GetCalleeSaveMethodFrameInfo(Runtime::kRefsAndArgs);
}
// This goes before IsProxyMethod since runtime methods have a null declaring class.
if (method->IsRuntimeMethod()) {
return runtime->GetRuntimeMethodFrameInfo(method);
}
if (method->IsProxyMethod()) {
// There is only one direct method of a proxy class: the constructor. A direct method is
// cloned from the original java.lang.reflect.Proxy and is executed as usual quick
// compiled method without any stubs. Therefore the method must have a OatQuickMethodHeader.
DCHECK(!method->IsDirect() && !method->IsConstructor())
<< "Constructors of proxy classes must have a OatQuickMethodHeader";
return runtime->GetCalleeSaveMethodFrameInfo(Runtime::kRefsAndArgs);
}
// The only remaining case is if the method is native and uses the generic JNI stub.
DCHECK(method->IsNative());
ClassLinker* class_linker = runtime->GetClassLinker();
const void* entry_point = runtime->GetInstrumentation()->GetQuickCodeFor(method, sizeof(void*));
DCHECK(class_linker->IsQuickGenericJniStub(entry_point)) << PrettyMethod(method);
// Generic JNI frame.
uint32_t handle_refs = GetNumberOfReferenceArgsWithoutReceiver(method) + 1;
size_t scope_size = HandleScope::SizeOf(handle_refs);
QuickMethodFrameInfo callee_info = runtime->GetCalleeSaveMethodFrameInfo(Runtime::kRefsAndArgs);
// Callee saves + handle scope + method ref + alignment
// Note: -sizeof(void*) since callee-save frame stores a whole method pointer.
size_t frame_size = RoundUp(
callee_info.FrameSizeInBytes() - sizeof(void*) + sizeof(ArtMethod*) + scope_size,
kStackAlignment);
return QuickMethodFrameInfo(frame_size, callee_info.CoreSpillMask(), callee_info.FpSpillMask());
}
void StackVisitor::WalkStack(bool include_transitions) {
DCHECK(thread_ == Thread::Current() || thread_->IsSuspended());
CHECK_EQ(cur_depth_, 0U);
bool exit_stubs_installed = Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled();
uint32_t instrumentation_stack_depth = 0;
size_t inlined_frames_count = 0;
for (const ManagedStack* current_fragment = thread_->GetManagedStack();
current_fragment != nullptr; current_fragment = current_fragment->GetLink()) {
cur_shadow_frame_ = current_fragment->GetTopShadowFrame();
cur_quick_frame_ = current_fragment->GetTopQuickFrame();
cur_quick_frame_pc_ = 0;
cur_oat_quick_method_header_ = nullptr;
if (cur_quick_frame_ != nullptr) { // Handle quick stack frames.
// Can't be both a shadow and a quick fragment.
DCHECK(current_fragment->GetTopShadowFrame() == nullptr);
ArtMethod* method = *cur_quick_frame_;
while (method != nullptr) {
cur_oat_quick_method_header_ = method->GetOatQuickMethodHeader(cur_quick_frame_pc_);
SanityCheckFrame();
if ((walk_kind_ == StackWalkKind::kIncludeInlinedFrames ||
walk_kind_ == StackWalkKind::kIncludeInlinedFramesNoResolve)
&& (cur_oat_quick_method_header_ != nullptr)
&& cur_oat_quick_method_header_->IsOptimized()) {
CodeInfo code_info = cur_oat_quick_method_header_->GetOptimizedCodeInfo();
CodeInfoEncoding encoding = code_info.ExtractEncoding();
uint32_t native_pc_offset =
cur_oat_quick_method_header_->NativeQuickPcOffset(cur_quick_frame_pc_);
StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset, encoding);
if (stack_map.IsValid() && stack_map.HasInlineInfo(encoding.stack_map_encoding)) {
InlineInfo inline_info = code_info.GetInlineInfoOf(stack_map, encoding);
DCHECK_EQ(current_inlining_depth_, 0u);
for (current_inlining_depth_ = inline_info.GetDepth(encoding.inline_info_encoding);
current_inlining_depth_ != 0;
--current_inlining_depth_) {
bool should_continue = VisitFrame();
if (UNLIKELY(!should_continue)) {
return;
}
cur_depth_++;
inlined_frames_count++;
}
}
}
bool should_continue = VisitFrame();
if (UNLIKELY(!should_continue)) {
return;
}
QuickMethodFrameInfo frame_info = GetCurrentQuickFrameInfo();
if (context_ != nullptr) {
context_->FillCalleeSaves(reinterpret_cast<uint8_t*>(cur_quick_frame_), frame_info);
}
// Compute PC for next stack frame from return PC.
size_t frame_size = frame_info.FrameSizeInBytes();
size_t return_pc_offset = frame_size - sizeof(void*);
uint8_t* return_pc_addr = reinterpret_cast<uint8_t*>(cur_quick_frame_) + return_pc_offset;
uintptr_t return_pc = *reinterpret_cast<uintptr_t*>(return_pc_addr);
if (UNLIKELY(exit_stubs_installed)) {
// While profiling, the return pc is restored from the side stack, except when walking
// the stack for an exception where the side stack will be unwound in VisitFrame.
if (reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc()) == return_pc) {
const instrumentation::InstrumentationStackFrame& instrumentation_frame =
GetInstrumentationStackFrame(thread_, instrumentation_stack_depth);
instrumentation_stack_depth++;
if (GetMethod() == Runtime::Current()->GetCalleeSaveMethod(Runtime::kSaveAll)) {
// Skip runtime save all callee frames which are used to deliver exceptions.
} else if (instrumentation_frame.interpreter_entry_) {
ArtMethod* callee = Runtime::Current()->GetCalleeSaveMethod(Runtime::kRefsAndArgs);
CHECK_EQ(GetMethod(), callee) << "Expected: " << PrettyMethod(callee) << " Found: "
<< PrettyMethod(GetMethod());
} else {
CHECK_EQ(instrumentation_frame.method_, GetMethod())
<< "Expected: " << PrettyMethod(instrumentation_frame.method_)
<< " Found: " << PrettyMethod(GetMethod());
}
if (num_frames_ != 0) {
// Check agreement of frame Ids only if num_frames_ is computed to avoid infinite
// recursion.
size_t frame_id = instrumentation::Instrumentation::ComputeFrameId(
thread_,
cur_depth_,
inlined_frames_count);
CHECK_EQ(instrumentation_frame.frame_id_, frame_id);
}
return_pc = instrumentation_frame.return_pc_;
}
}
cur_quick_frame_pc_ = return_pc;
uint8_t* next_frame = reinterpret_cast<uint8_t*>(cur_quick_frame_) + frame_size;
cur_quick_frame_ = reinterpret_cast<ArtMethod**>(next_frame);
if (kDebugStackWalk) {
LOG(INFO) << PrettyMethod(method) << "@" << method << " size=" << frame_size
<< std::boolalpha
<< " optimized=" << (cur_oat_quick_method_header_ != nullptr &&
cur_oat_quick_method_header_->IsOptimized())
<< " native=" << method->IsNative()
<< std::noboolalpha
<< " entrypoints=" << method->GetEntryPointFromQuickCompiledCode()
<< "," << method->GetEntryPointFromJni()
<< " next=" << *cur_quick_frame_;
}
cur_depth_++;
method = *cur_quick_frame_;
}
} else if (cur_shadow_frame_ != nullptr) {
do {
SanityCheckFrame();
bool should_continue = VisitFrame();
if (UNLIKELY(!should_continue)) {
return;
}
cur_depth_++;
cur_shadow_frame_ = cur_shadow_frame_->GetLink();
} while (cur_shadow_frame_ != nullptr);
}
if (include_transitions) {
bool should_continue = VisitFrame();
if (!should_continue) {
return;
}
}
cur_depth_++;
}
if (num_frames_ != 0) {
CHECK_EQ(cur_depth_, num_frames_);
}
}
void JavaFrameRootInfo::Describe(std::ostream& os) const {
const StackVisitor* visitor = stack_visitor_;
CHECK(visitor != nullptr);
os << "Type=" << GetType() << " thread_id=" << GetThreadId() << " location=" <<
visitor->DescribeLocation() << " vreg=" << vreg_;
}
int StackVisitor::GetVRegOffsetFromQuickCode(const DexFile::CodeItem* code_item,
uint32_t core_spills, uint32_t fp_spills,
size_t frame_size, int reg, InstructionSet isa) {
size_t pointer_size = InstructionSetPointerSize(isa);
if (kIsDebugBuild) {
auto* runtime = Runtime::Current();
if (runtime != nullptr) {
CHECK_EQ(runtime->GetClassLinker()->GetImagePointerSize(), pointer_size);
}
}
DCHECK_ALIGNED(frame_size, kStackAlignment);
DCHECK_NE(reg, -1);
int spill_size = POPCOUNT(core_spills) * GetBytesPerGprSpillLocation(isa)
+ POPCOUNT(fp_spills) * GetBytesPerFprSpillLocation(isa)
+ sizeof(uint32_t); // Filler.
int num_regs = code_item->registers_size_ - code_item->ins_size_;
int temp_threshold = code_item->registers_size_;
const int max_num_special_temps = 1;
if (reg == temp_threshold) {
// The current method pointer corresponds to special location on stack.
return 0;
} else if (reg >= temp_threshold + max_num_special_temps) {
/*
* Special temporaries may have custom locations and the logic above deals with that.
* However, non-special temporaries are placed relative to the outs.
*/
int temps_start = code_item->outs_size_ * sizeof(uint32_t) + pointer_size /* art method */;
int relative_offset = (reg - (temp_threshold + max_num_special_temps)) * sizeof(uint32_t);
return temps_start + relative_offset;
} else if (reg < num_regs) {
int locals_start = frame_size - spill_size - num_regs * sizeof(uint32_t);
return locals_start + (reg * sizeof(uint32_t));
} else {
// Handle ins.
return frame_size + ((reg - num_regs) * sizeof(uint32_t)) + pointer_size /* art method */;
}
}
void LockCountData::AddMonitor(Thread* self, mirror::Object* obj) {
if (obj == nullptr) {
return;
}
// If there's an error during enter, we won't have locked the monitor. So check there's no
// exception.
if (self->IsExceptionPending()) {
return;
}
if (monitors_ == nullptr) {
monitors_.reset(new std::vector<mirror::Object*>());
}
monitors_->push_back(obj);
}
void LockCountData::RemoveMonitorOrThrow(Thread* self, const mirror::Object* obj) {
if (obj == nullptr) {
return;
}
bool found_object = false;
if (monitors_ != nullptr) {
// We need to remove one pointer to ref, as duplicates are used for counting recursive locks.
// We arbitrarily choose the first one.
auto it = std::find(monitors_->begin(), monitors_->end(), obj);
if (it != monitors_->end()) {
monitors_->erase(it);
found_object = true;
}
}
if (!found_object) {
// The object wasn't found. Time for an IllegalMonitorStateException.
// The order here isn't fully clear. Assume that any other pending exception is swallowed.
// TODO: Maybe make already pending exception a suppressed exception.
self->ClearException();
self->ThrowNewExceptionF("Ljava/lang/IllegalMonitorStateException;",
"did not lock monitor on object of type '%s' before unlocking",
PrettyTypeOf(const_cast<mirror::Object*>(obj)).c_str());
}
}
// Helper to unlock a monitor. Must be NO_THREAD_SAFETY_ANALYSIS, as we can't statically show
// that the object was locked.
void MonitorExitHelper(Thread* self, mirror::Object* obj) NO_THREAD_SAFETY_ANALYSIS {
DCHECK(self != nullptr);
DCHECK(obj != nullptr);
obj->MonitorExit(self);
}
bool LockCountData::CheckAllMonitorsReleasedOrThrow(Thread* self) {
DCHECK(self != nullptr);
if (monitors_ != nullptr) {
if (!monitors_->empty()) {
// There may be an exception pending, if the method is terminating abruptly. Clear it.
// TODO: Should we add this as a suppressed exception?
self->ClearException();
// OK, there are monitors that are still locked. To enforce structured locking (and avoid
// deadlocks) we unlock all of them before we raise the IllegalMonitorState exception.
for (mirror::Object* obj : *monitors_) {
MonitorExitHelper(self, obj);
// If this raised an exception, ignore. TODO: Should we add this as suppressed
// exceptions?
if (self->IsExceptionPending()) {
self->ClearException();
}
}
// Raise an exception, just give the first object as the sample.
mirror::Object* first = (*monitors_)[0];
self->ThrowNewExceptionF("Ljava/lang/IllegalMonitorStateException;",
"did not unlock monitor on object of type '%s'",
PrettyTypeOf(first).c_str());
// To make sure this path is not triggered again, clean out the monitors.
monitors_->clear();
return false;
}
}
return true;
}
} // namespace art