/*
* 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 <limits>
#include "android-base/stringprintf.h"
#include "arch/context.h"
#include "art_method-inl.h"
#include "base/callee_save_type.h"
#include "base/enums.h"
#include "base/hex_dump.h"
#include "dex/dex_file_types.h"
#include "entrypoints/entrypoint_utils-inl.h"
#include "entrypoints/quick/callee_save_frame.h"
#include "entrypoints/runtime_asm_entrypoints.h"
#include "gc/space/image_space.h"
#include "gc/space/space-inl.h"
#include "interpreter/mterp/nterp.h"
#include "interpreter/shadow_frame-inl.h"
#include "jit/jit.h"
#include "jit/jit_code_cache.h"
#include "linear_alloc.h"
#include "managed_stack.h"
#include "mirror/class-inl.h"
#include "mirror/object-inl.h"
#include "mirror/object_array-inl.h"
#include "nterp_helpers.h"
#include "oat_quick_method_header.h"
#include "obj_ptr-inl.h"
#include "quick/quick_method_frame_info.h"
#include "runtime.h"
#include "thread.h"
#include "thread_list.h"
namespace art {
using android::base::StringPrintf;
static constexpr bool kDebugStackWalk = false;
StackVisitor::StackVisitor(Thread* thread,
Context* context,
StackWalkKind walk_kind,
bool check_suspended)
: StackVisitor(thread, context, walk_kind, 0, check_suspended) {}
StackVisitor::StackVisitor(Thread* thread,
Context* context,
StackWalkKind walk_kind,
size_t num_frames,
bool check_suspended)
: 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),
cur_inline_info_(nullptr, CodeInfo()),
cur_stack_map_(0, StackMap()),
context_(context),
check_suspended_(check_suspended) {
if (check_suspended_) {
DCHECK(thread == Thread::Current() || thread->IsSuspended()) << *thread;
}
}
CodeInfo* StackVisitor::GetCurrentInlineInfo() const {
DCHECK(!(*cur_quick_frame_)->IsNative());
const OatQuickMethodHeader* header = GetCurrentOatQuickMethodHeader();
if (cur_inline_info_.first != header) {
cur_inline_info_ = std::make_pair(header, CodeInfo::DecodeInlineInfoOnly(header));
}
return &cur_inline_info_.second;
}
StackMap* StackVisitor::GetCurrentStackMap() const {
DCHECK(!(*cur_quick_frame_)->IsNative());
const OatQuickMethodHeader* header = GetCurrentOatQuickMethodHeader();
if (cur_stack_map_.first != cur_quick_frame_pc_) {
uint32_t pc = header->NativeQuickPcOffset(cur_quick_frame_pc_);
cur_stack_map_ = std::make_pair(cur_quick_frame_pc_,
GetCurrentInlineInfo()->GetStackMapForNativePcOffset(pc));
}
return &cur_stack_map_.second;
}
ArtMethod* StackVisitor::GetMethod() const {
if (cur_shadow_frame_ != nullptr) {
return cur_shadow_frame_->GetMethod();
} else if (cur_quick_frame_ != nullptr) {
if (IsInInlinedFrame()) {
CodeInfo* code_info = GetCurrentInlineInfo();
DCHECK(walk_kind_ != StackWalkKind::kSkipInlinedFrames);
return GetResolvedMethod(*GetCurrentQuickFrame(), *code_info, current_inline_frames_);
} 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()) {
return current_inline_frames_.back().GetDexPc();
} else if (cur_oat_quick_method_header_ == nullptr) {
return dex::kDexNoIndex;
} else if ((*GetCurrentQuickFrame())->IsNative()) {
return cur_oat_quick_method_header_->ToDexPc(
GetCurrentQuickFrame(), cur_quick_frame_pc_, abort_on_failure);
} else if (cur_oat_quick_method_header_->IsOptimized()) {
StackMap* stack_map = GetCurrentStackMap();
CHECK(stack_map->IsValid()) << "StackMap not found for " << std::hex << cur_quick_frame_pc_;
return stack_map->GetDexPc();
} else {
DCHECK(cur_oat_quick_method_header_->IsNterpMethodHeader());
return NterpGetDexPC(cur_quick_frame_);
}
} else {
return 0;
}
}
std::vector<uint32_t> StackVisitor::ComputeDexPcList(uint32_t handler_dex_pc) const {
std::vector<uint32_t> result;
if (cur_shadow_frame_ == nullptr && cur_quick_frame_ != nullptr && IsInInlinedFrame()) {
const BitTableRange<InlineInfo>& infos = current_inline_frames_;
DCHECK_NE(infos.size(), 0u);
// Outermost dex_pc.
result.push_back(GetCurrentStackMap()->GetDexPc());
// The mid dex_pcs. Note that we skip the last one since we want to change that for
// `handler_dex_pc`.
for (size_t index = 0; index < infos.size() - 1; ++index) {
result.push_back(infos[index].GetDexPc());
}
}
// The innermost dex_pc has to be the handler dex_pc. In the case of no inline frames, it will be
// just the one dex_pc. In the case of inlining we will be replacing the innermost InlineInfo's
// dex_pc with this one.
result.push_back(handler_dex_pc);
return result;
}
extern "C" mirror::Object* artQuickGetProxyThisObject(ArtMethod** sp)
REQUIRES_SHARED(Locks::mutator_lock_);
ObjPtr<mirror::Object> StackVisitor::GetThisObject() const {
DCHECK_EQ(Runtime::Current()->GetClassLinker()->GetImagePointerSize(), kRuntimePointerSize);
ArtMethod* m = GetMethod();
if (m->IsStatic()) {
return nullptr;
} else if (m->IsNative()) {
if (cur_quick_frame_ != nullptr) {
// The `this` reference is stored in the first out vreg in the caller's frame.
const size_t frame_size = GetCurrentQuickFrameInfo().FrameSizeInBytes();
auto* stack_ref = reinterpret_cast<StackReference<mirror::Object>*>(
reinterpret_cast<uint8_t*>(cur_quick_frame_) + frame_size + sizeof(ArtMethod*));
return stack_ref->AsMirrorPtr();
} 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 {
CodeItemDataAccessor accessor(m->DexInstructionData());
if (!accessor.HasCodeItem()) {
UNIMPLEMENTED(ERROR) << "Failed to determine this object of abstract or proxy method: "
<< ArtMethod::PrettyMethod(m);
return nullptr;
} else {
uint16_t reg = accessor.RegistersSize() - accessor.InsSize();
uint32_t value = 0;
if (!GetVReg(m, reg, kReferenceVReg, &value)) {
return nullptr;
}
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,
std::optional<DexRegisterLocation> location,
bool need_full_register_list) 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;
}
bool result = false;
if (cur_oat_quick_method_header_->IsNterpMethodHeader()) {
result = true;
*val = (kind == kReferenceVReg)
? NterpGetVRegReference(cur_quick_frame_, vreg)
: NterpGetVReg(cur_quick_frame_, vreg);
} else {
DCHECK(cur_oat_quick_method_header_->IsOptimized());
if (location.has_value() && kind != kReferenceVReg) {
uint32_t val2 = *val;
// The caller already known the register location, so we can use the faster overload
// which does not decode the stack maps.
result = GetVRegFromOptimizedCode(location.value(), val);
// Compare to the slower overload.
DCHECK_EQ(result, GetVRegFromOptimizedCode(m, vreg, kind, &val2, need_full_register_list));
DCHECK_EQ(*val, val2);
} else {
result = GetVRegFromOptimizedCode(m, vreg, kind, val, need_full_register_list);
}
}
if (kind == kReferenceVReg) {
// Perform a read barrier in case we are in a different thread and GC is ongoing.
mirror::Object* out = reinterpret_cast<mirror::Object*>(static_cast<uintptr_t>(*val));
uintptr_t ptr_out = reinterpret_cast<uintptr_t>(GcRoot<mirror::Object>(out).Read());
DCHECK_LT(ptr_out, std::numeric_limits<uint32_t>::max());
*val = static_cast<uint32_t>(ptr_out);
}
return result;
} 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;
}
}
size_t StackVisitor::GetNumberOfRegisters(CodeInfo* code_info, int depth) const {
return depth == 0
? code_info->GetNumberOfDexRegisters()
: current_inline_frames_[depth - 1].GetNumberOfDexRegisters();
}
bool StackVisitor::GetVRegFromOptimizedCode(ArtMethod* m,
uint16_t vreg,
VRegKind kind,
uint32_t* val,
bool need_full_register_list) const {
DCHECK_EQ(m, GetMethod());
// Can't be null or how would we compile its instructions?
DCHECK(m->GetCodeItem() != nullptr) << m->PrettyMethod();
const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
CodeInfo code_info(method_header);
uint32_t native_pc_offset = method_header->NativeQuickPcOffset(cur_quick_frame_pc_);
StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset);
DCHECK(stack_map.IsValid());
DexRegisterMap dex_register_map = (IsInInlinedFrame() && !need_full_register_list)
? code_info.GetInlineDexRegisterMapOf(stack_map, current_inline_frames_.back())
: code_info.GetDexRegisterMapOf(stack_map,
/* first= */ 0,
GetNumberOfRegisters(&code_info, InlineDepth()));
if (dex_register_map.empty()) {
return false;
}
const size_t number_of_dex_registers = dex_register_map.size();
DCHECK_LT(vreg, number_of_dex_registers);
DexRegisterLocation::Kind location_kind = dex_register_map[vreg].GetKind();
switch (location_kind) {
case DexRegisterLocation::Kind::kInStack: {
const int32_t offset = dex_register_map[vreg].GetStackOffsetInBytes();
BitMemoryRegion stack_mask = code_info.GetStackMaskOf(stack_map);
if (kind == kReferenceVReg && !stack_mask.LoadBit(offset / kFrameSlotSize)) {
return false;
}
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: {
uint32_t register_mask = code_info.GetRegisterMaskOf(stack_map);
uint32_t reg = dex_register_map[vreg].GetMachineRegister();
if (kind == kReferenceVReg && !(register_mask & (1 << reg))) {
return false;
}
return GetRegisterIfAccessible(reg, location_kind, val);
}
case DexRegisterLocation::Kind::kInRegisterHigh:
case DexRegisterLocation::Kind::kInFpuRegister:
case DexRegisterLocation::Kind::kInFpuRegisterHigh: {
if (kind == kReferenceVReg) {
return false;
}
uint32_t reg = dex_register_map[vreg].GetMachineRegister();
return GetRegisterIfAccessible(reg, location_kind, val);
}
case DexRegisterLocation::Kind::kConstant: {
uint32_t result = dex_register_map[vreg].GetConstant();
if (kind == kReferenceVReg && result != 0) {
return false;
}
*val = result;
return true;
}
case DexRegisterLocation::Kind::kNone:
return false;
default:
LOG(FATAL) << "Unexpected location kind " << dex_register_map[vreg].GetKind();
UNREACHABLE();
}
}
bool StackVisitor::GetVRegFromOptimizedCode(DexRegisterLocation location, uint32_t* val) const {
switch (location.GetKind()) {
case DexRegisterLocation::Kind::kInvalid:
break;
case DexRegisterLocation::Kind::kInStack: {
const uint8_t* sp = reinterpret_cast<const uint8_t*>(cur_quick_frame_);
*val = *reinterpret_cast<const uint32_t*>(sp + location.GetStackOffsetInBytes());
return true;
}
case DexRegisterLocation::Kind::kInRegister:
case DexRegisterLocation::Kind::kInRegisterHigh:
case DexRegisterLocation::Kind::kInFpuRegister:
case DexRegisterLocation::Kind::kInFpuRegisterHigh:
return GetRegisterIfAccessible(location.GetMachineRegister(), location.GetKind(), val);
case DexRegisterLocation::Kind::kConstant:
*val = location.GetConstant();
return true;
case DexRegisterLocation::Kind::kNone:
return false;
}
LOG(FATAL) << "Unexpected location kind " << location.GetKind();
UNREACHABLE();
}
bool StackVisitor::GetRegisterIfAccessible(uint32_t reg,
DexRegisterLocation::Kind location_kind,
uint32_t* val) const {
const bool is_float = (location_kind == DexRegisterLocation::Kind::kInFpuRegister) ||
(location_kind == DexRegisterLocation::Kind::kInFpuRegisterHigh);
if (kRuntimeISA == InstructionSet::kX86 && is_float) {
// X86 float registers are 64-bit and each XMM register is provided as two separate
// 32-bit registers by the context.
reg = (location_kind == DexRegisterLocation::Kind::kInFpuRegisterHigh)
? (2 * reg + 1)
: (2 * reg);
}
if (!IsAccessibleRegister(reg, is_float)) {
return false;
}
uintptr_t ptr_val = GetRegister(reg, is_float);
const bool target64 = Is64BitInstructionSet(kRuntimeISA);
if (target64) {
const bool is_high = (location_kind == DexRegisterLocation::Kind::kInRegisterHigh) ||
(location_kind == DexRegisterLocation::Kind::kInFpuRegisterHigh);
int64_t value_long = static_cast<int64_t>(ptr_val);
ptr_val = static_cast<uintptr_t>(is_high ? High32Bits(value_long) : Low32Bits(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(cur_shadow_frame_ != nullptr);
*val = cur_shadow_frame_->GetVRegLong(vreg);
return true;
}
if (cur_oat_quick_method_header_->IsNterpMethodHeader()) {
uint64_t val_lo = NterpGetVReg(cur_quick_frame_, vreg);
uint64_t val_hi = NterpGetVReg(cur_quick_frame_, vreg + 1);
*val = (val_hi << 32) + val_lo;
return true;
}
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);
}
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;
}
ShadowFrame* StackVisitor::PrepareSetVReg(ArtMethod* m, uint16_t vreg, bool wide) {
CodeItemDataAccessor accessor(m->DexInstructionData());
if (!accessor.HasCodeItem()) {
return nullptr;
}
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 = accessor.RegistersSize();
shadow_frame = thread_->FindOrCreateDebuggerShadowFrame(frame_id, num_regs, m, GetDexPc());
CHECK(shadow_frame != nullptr);
// Remember the vreg(s) 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 (wide) {
thread_->GetUpdatedVRegFlags(frame_id)[vreg + 1] = true;
}
}
return shadow_frame;
}
bool StackVisitor::SetVReg(ArtMethod* m, uint16_t vreg, uint32_t new_value, VRegKind kind) {
DCHECK(kind == kIntVReg || kind == kFloatVReg);
ShadowFrame* shadow_frame = PrepareSetVReg(m, vreg, /* wide= */ false);
if (shadow_frame == nullptr) {
return false;
}
shadow_frame->SetVReg(vreg, new_value);
return true;
}
bool StackVisitor::SetVRegReference(ArtMethod* m, uint16_t vreg, ObjPtr<mirror::Object> new_value) {
ShadowFrame* shadow_frame = PrepareSetVReg(m, vreg, /* wide= */ false);
if (shadow_frame == nullptr) {
return false;
}
shadow_frame->SetVRegReference(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();
}
ShadowFrame* shadow_frame = PrepareSetVReg(m, vreg, /* wide= */ true);
if (shadow_frame == nullptr) {
return false;
}
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::GetReturnPcAddr() const {
uintptr_t sp = reinterpret_cast<uintptr_t>(GetCurrentQuickFrame());
DCHECK_NE(sp, 0u);
return sp + GetCurrentQuickFrameInfo().GetReturnPcOffset();
}
uintptr_t StackVisitor::GetReturnPc() const {
return *reinterpret_cast<uintptr_t*>(GetReturnPcAddr());
}
void StackVisitor::SetReturnPc(uintptr_t new_ret_pc) {
*reinterpret_cast<uintptr_t*>(GetReturnPcAddr()) = 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 REQUIRES_SHARED(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 REQUIRES_SHARED(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 += m->PrettyMethod();
result += StringPrintf("' at dex PC 0x%04x", GetDexPc());
if (!IsShadowFrame()) {
result += StringPrintf(" (native PC %p)", reinterpret_cast<void*>(GetCurrentQuickFramePc()));
}
return result;
}
void StackVisitor::SetMethod(ArtMethod* method) {
DCHECK(GetMethod() != nullptr);
if (cur_shadow_frame_ != nullptr) {
cur_shadow_frame_->SetMethod(method);
} else {
DCHECK(cur_quick_frame_ != nullptr);
CHECK(!IsInInlinedFrame()) << "We do not support setting inlined method's ArtMethod: "
<< GetMethod()->PrettyMethod() << " is inlined into "
<< GetOuterMethod()->PrettyMethod();
*cur_quick_frame_ = method;
}
}
void StackVisitor::ValidateFrame() const {
if (!kIsDebugBuild) {
return;
}
ArtMethod* method = GetMethod();
ObjPtr<mirror::Class> 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.
// We get the canonical method as copied methods may have been allocated
// by a different class loader.
const PointerSize ptrSize = runtime->GetClassLinker()->GetImagePointerSize();
ArtMethod* canonical = method->GetCanonicalMethod(ptrSize);
ObjPtr<mirror::Class> klass = canonical->GetDeclaringClass();
LinearAlloc* const class_linear_alloc = (klass != nullptr)
? runtime->GetClassLinker()->GetAllocatorForClassLoader(klass->GetClassLoader())
: linear_alloc;
if (!class_linear_alloc->Contains(canonical)) {
// 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*>(canonical) - image_space->Begin();
if (methods.Contains(offset) || runtime_methods.Contains(offset)) {
in_image = true;
break;
}
}
}
CHECK(in_image) << canonical->PrettyMethod() << " not in linear alloc or image";
}
}
if (cur_quick_frame_ != nullptr) {
// Frame consistency checks.
size_t frame_size = GetCurrentQuickFrameInfo().FrameSizeInBytes();
CHECK_NE(frame_size, 0u);
// For compiled code, we could try to have a rough guess at an upper size we expect
// to see for a frame:
// 256 registers
// 2 words HandleScope overhead
// 3+3 register spills
// const size_t kMaxExpectedFrameSize = (256 + 2 + 3 + 3) * sizeof(word);
const size_t kMaxExpectedFrameSize = interpreter::kNterpMaxFrame;
CHECK_LE(frame_size, kMaxExpectedFrameSize) << method->PrettyMethod();
size_t return_pc_offset = GetCurrentQuickFrameInfo().GetReturnPcOffset();
CHECK_LT(return_pc_offset, frame_size);
}
}
QuickMethodFrameInfo StackVisitor::GetCurrentQuickFrameInfo() const {
if (cur_oat_quick_method_header_ != nullptr) {
if (cur_oat_quick_method_header_->IsOptimized()) {
return cur_oat_quick_method_header_->GetFrameInfo();
} else {
DCHECK(cur_oat_quick_method_header_->IsNterpMethodHeader());
return NterpFrameInfo(cur_quick_frame_);
}
}
ArtMethod* method = GetMethod();
Runtime* runtime = Runtime::Current();
if (method->IsAbstract()) {
return RuntimeCalleeSaveFrame::GetMethodFrameInfo(CalleeSaveType::kSaveRefsAndArgs);
}
// 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 RuntimeCalleeSaveFrame::GetMethodFrameInfo(CalleeSaveType::kSaveRefsAndArgs);
}
// The only remaining cases are for native methods that either
// - use the Generic JNI stub, called either directly or through some
// (resolution, instrumentation) trampoline; or
// - fake a Generic JNI frame in art_jni_dlsym_lookup_critical_stub.
DCHECK(method->IsNative());
// Generic JNI frame is just like the SaveRefsAndArgs frame.
// Note that HandleScope, if any, is below the frame.
return RuntimeCalleeSaveFrame::GetMethodFrameInfo(CalleeSaveType::kSaveRefsAndArgs);
}
uint8_t* StackVisitor::GetShouldDeoptimizeFlagAddr() const REQUIRES_SHARED(Locks::mutator_lock_) {
DCHECK(GetCurrentOatQuickMethodHeader()->HasShouldDeoptimizeFlag());
QuickMethodFrameInfo frame_info = GetCurrentQuickFrameInfo();
size_t frame_size = frame_info.FrameSizeInBytes();
uint8_t* sp = reinterpret_cast<uint8_t*>(GetCurrentQuickFrame());
size_t core_spill_size =
POPCOUNT(frame_info.CoreSpillMask()) * GetBytesPerGprSpillLocation(kRuntimeISA);
size_t fpu_spill_size =
POPCOUNT(frame_info.FpSpillMask()) * GetBytesPerFprSpillLocation(kRuntimeISA);
size_t offset = frame_size - core_spill_size - fpu_spill_size - kShouldDeoptimizeFlagSize;
uint8_t* should_deoptimize_addr = sp + offset;
DCHECK_EQ(*should_deoptimize_addr & ~static_cast<uint8_t>(DeoptimizeFlagValue::kAll), 0);
return should_deoptimize_addr;
}
template <StackVisitor::CountTransitions kCount>
void StackVisitor::WalkStack(bool include_transitions) {
if (check_suspended_) {
DCHECK(thread_ == Thread::Current() || thread_->IsSuspended());
}
CHECK_EQ(cur_depth_, 0U);
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;
DCHECK(cur_oat_quick_method_header_ == nullptr);
if (kDebugStackWalk) {
LOG(INFO) << "Tid=" << thread_-> GetThreadId()
<< ", ManagedStack fragement: " << current_fragment;
}
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_;
DCHECK(method != nullptr);
bool header_retrieved = false;
if (method->IsNative()) {
// We do not have a PC for the first frame, so we cannot simply use
// ArtMethod::GetOatQuickMethodHeader() as we're unable to distinguish there
// between GenericJNI frame and JIT-compiled JNI stub; the entrypoint may have
// changed since the frame was entered. The top quick frame tag indicates
// GenericJNI here, otherwise it's either AOT-compiled or JNI-compiled JNI stub.
if (UNLIKELY(current_fragment->GetTopQuickFrameGenericJniTag())) {
// The generic JNI does not have any method header.
cur_oat_quick_method_header_ = nullptr;
} else if (UNLIKELY(current_fragment->GetTopQuickFrameJitJniTag())) {
// Should be JITed code.
Runtime* runtime = Runtime::Current();
const void* code = runtime->GetJit()->GetCodeCache()->GetJniStubCode(method);
CHECK(code != nullptr) << method->PrettyMethod();
cur_oat_quick_method_header_ = OatQuickMethodHeader::FromCodePointer(code);
} else {
// We are sure we are not running GenericJni here. Though the entry point could still be
// GenericJnistub. The entry point is usually JITed or AOT code. It could be lso a
// resolution stub if the class isn't visibly initialized yet.
const void* existing_entry_point = method->GetEntryPointFromQuickCompiledCode();
CHECK(existing_entry_point != nullptr);
Runtime* runtime = Runtime::Current();
ClassLinker* class_linker = runtime->GetClassLinker();
// Check whether we can quickly get the header from the current entrypoint.
if (!class_linker->IsQuickGenericJniStub(existing_entry_point) &&
!class_linker->IsQuickResolutionStub(existing_entry_point)) {
cur_oat_quick_method_header_ =
OatQuickMethodHeader::FromEntryPoint(existing_entry_point);
} else {
const void* code = method->GetOatMethodQuickCode(class_linker->GetImagePointerSize());
if (code != nullptr) {
cur_oat_quick_method_header_ = OatQuickMethodHeader::FromEntryPoint(code);
} else {
// This must be a JITted JNI stub frame. For non-debuggable runtimes we only generate
// JIT stubs if there are no AOT stubs for native methods. Since we checked for AOT
// code earlier, we must be running JITed code. For debuggable runtimes we might have
// JIT code even when AOT code is present but we tag SP in JITed JNI stubs
// in debuggable runtimes. This case is handled earlier.
CHECK(runtime->GetJit() != nullptr);
code = runtime->GetJit()->GetCodeCache()->GetJniStubCode(method);
CHECK(code != nullptr) << method->PrettyMethod();
cur_oat_quick_method_header_ = OatQuickMethodHeader::FromCodePointer(code);
}
}
}
header_retrieved = true;
}
while (method != nullptr) {
if (!header_retrieved) {
cur_oat_quick_method_header_ = method->GetOatQuickMethodHeader(cur_quick_frame_pc_);
}
header_retrieved = false; // Force header retrieval in next iteration.
if (kDebugStackWalk) {
LOG(INFO) << "Early print: Tid=" << thread_-> GetThreadId() << ", method: "
<< ArtMethod::PrettyMethod(method) << "@" << method;
}
ValidateFrame();
if ((walk_kind_ == StackWalkKind::kIncludeInlinedFrames)
&& (cur_oat_quick_method_header_ != nullptr)
&& cur_oat_quick_method_header_->IsOptimized()
&& !method->IsNative() // JNI methods cannot have any inlined frames.
&& CodeInfo::HasInlineInfo(cur_oat_quick_method_header_->GetOptimizedCodeInfoPtr())) {
DCHECK_NE(cur_quick_frame_pc_, 0u);
CodeInfo* code_info = GetCurrentInlineInfo();
StackMap* stack_map = GetCurrentStackMap();
if (stack_map->IsValid() && stack_map->HasInlineInfo()) {
DCHECK_EQ(current_inline_frames_.size(), 0u);
for (current_inline_frames_ = code_info->GetInlineInfosOf(*stack_map);
!current_inline_frames_.empty();
current_inline_frames_.pop_back()) {
bool should_continue = VisitFrame();
if (UNLIKELY(!should_continue)) {
return;
}
cur_depth_++;
}
}
}
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();
uintptr_t return_pc_addr = GetReturnPcAddr();
cur_quick_frame_pc_ = *reinterpret_cast<uintptr_t*>(return_pc_addr);
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) << "Tid=" << thread_-> GetThreadId() << ", method: "
<< ArtMethod::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->IsNative() ? method->GetEntryPointFromJni() : nullptr)
<< " next=" << *cur_quick_frame_;
}
if (kCount == CountTransitions::kYes || !method->IsRuntimeMethod()) {
cur_depth_++;
}
method = *cur_quick_frame_;
}
// We reached a transition frame, it doesn't have a method header.
cur_oat_quick_method_header_ = nullptr;
} else if (cur_shadow_frame_ != nullptr) {
do {
if (kDebugStackWalk) {
ArtMethod* method = cur_shadow_frame_->GetMethod();
LOG(INFO) << "Tid=" << thread_-> GetThreadId() << ", method: "
<< ArtMethod::PrettyMethod(method) << "@" << method
<< ", ShadowFrame";
}
ValidateFrame();
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;
}
}
if (kCount == CountTransitions::kYes) {
cur_depth_++;
}
}
if (num_frames_ != 0) {
CHECK_EQ(cur_depth_, num_frames_);
}
}
template void StackVisitor::WalkStack<StackVisitor::CountTransitions::kYes>(bool);
template void StackVisitor::WalkStack<StackVisitor::CountTransitions::kNo>(bool);
} // namespace art