/*
* 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/runtime_asm_entrypoints.h"
#include "gc_map.h"
#include "gc/space/image_space.h"
#include "gc/space/space-inl.h"
#include "linear_alloc.h"
#include "mirror/class-inl.h"
#include "mirror/object-inl.h"
#include "mirror/object_array-inl.h"
#include "quick/quick_method_frame_info.h"
#include "runtime.h"
#include "thread.h"
#include "thread_list.h"
#include "verify_object-inl.h"
#include "vmap_table.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),
num_frames_(num_frames),
cur_depth_(0),
context_(context) {
DCHECK(thread == Thread::Current() || thread->IsSuspended()) << *thread;
}
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) {
return GetMethod()->ToDexPc(cur_quick_frame_pc_, abort_on_failure);
} else {
return 0;
}
}
extern "C" mirror::Object* artQuickGetProxyThisObject(ArtMethod** sp)
SHARED_LOCKS_REQUIRED(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_) + m->GetHandleScopeOffset().SizeValue());
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 GetMethod()->NativeQuickPcOffset(cur_quick_frame_pc_);
}
bool StackVisitor::IsReferenceVReg(ArtMethod* m, uint16_t vreg) {
// Process register map (which native and runtime methods don't have)
if (m->IsNative() || m->IsRuntimeMethod() || m->IsProxyMethod()) {
return false;
}
if (m->IsOptimized(sizeof(void*))) {
return true; // TODO: Implement.
}
const uint8_t* native_gc_map = m->GetNativeGcMap(sizeof(void*));
CHECK(native_gc_map != nullptr) << PrettyMethod(m);
const DexFile::CodeItem* code_item = m->GetCodeItem();
// Can't be null or how would we compile its instructions?
DCHECK(code_item != nullptr) << PrettyMethod(m);
NativePcOffsetToReferenceMap map(native_gc_map);
size_t num_regs = std::min(map.RegWidth() * 8, static_cast<size_t>(code_item->registers_size_));
const uint8_t* reg_bitmap = nullptr;
if (num_regs > 0) {
Runtime* runtime = Runtime::Current();
const void* entry_point = runtime->GetInstrumentation()->GetQuickCodeFor(m, sizeof(void*));
uintptr_t native_pc_offset = m->NativeQuickPcOffset(GetCurrentQuickFramePc(), entry_point);
reg_bitmap = map.FindBitMap(native_pc_offset);
DCHECK(reg_bitmap != nullptr);
}
// Does this register hold a reference?
return vreg < num_regs && TestBitmap(vreg, reg_bitmap);
}
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());
if (m->IsOptimized(sizeof(void*))) {
return GetVRegFromOptimizedCode(m, vreg, kind, val);
} else {
return GetVRegFromQuickCode(m, vreg, kind, val);
}
} else {
DCHECK(cur_shadow_frame_ != nullptr);
*val = cur_shadow_frame_->GetVReg(vreg);
return true;
}
}
bool StackVisitor::GetVRegFromQuickCode(ArtMethod* m, uint16_t vreg, VRegKind kind,
uint32_t* val) const {
const void* code_pointer = m->GetQuickOatCodePointer(sizeof(void*));
DCHECK(code_pointer != nullptr);
const VmapTable vmap_table(m->GetVmapTable(code_pointer, sizeof(void*)));
QuickMethodFrameInfo frame_info = m->GetQuickFrameInfo(code_pointer);
uint32_t vmap_offset;
// TODO: IsInContext stops before spotting floating point registers.
if (vmap_table.IsInContext(vreg, kind, &vmap_offset)) {
bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
uint32_t reg = vmap_table.ComputeRegister(spill_mask, vmap_offset, kind);
return GetRegisterIfAccessible(reg, kind, val);
} else {
const DexFile::CodeItem* code_item = m->GetCodeItem();
DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be null or how would we compile
// its instructions?
*val = *GetVRegAddrFromQuickCode(cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
return true;
}
}
bool StackVisitor::GetVRegFromOptimizedCode(ArtMethod* m, uint16_t vreg, VRegKind kind,
uint32_t* val) const {
const void* code_pointer = m->GetQuickOatCodePointer(sizeof(void*));
DCHECK(code_pointer != nullptr);
uint32_t native_pc_offset = m->NativeQuickPcOffset(cur_quick_frame_pc_);
CodeInfo code_info = m->GetOptimizedCodeInfo();
StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset);
const DexFile::CodeItem* code_item = m->GetCodeItem();
DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be null or how would we compile
// its instructions?
DCHECK_LT(vreg, code_item->registers_size_);
uint16_t number_of_dex_registers = code_item->registers_size_;
DexRegisterMap dex_register_map =
code_info.GetDexRegisterMapOf(stack_map, number_of_dex_registers);
DexRegisterLocation::Kind location_kind =
dex_register_map.GetLocationKind(vreg, number_of_dex_registers, code_info);
switch (location_kind) {
case DexRegisterLocation::Kind::kInStack: {
const int32_t offset =
dex_register_map.GetStackOffsetInBytes(vreg, number_of_dex_registers, code_info);
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::kInFpuRegister: {
uint32_t reg = dex_register_map.GetMachineRegister(vreg, number_of_dex_registers, code_info);
return GetRegisterIfAccessible(reg, kind, val);
}
case DexRegisterLocation::Kind::kConstant:
*val = dex_register_map.GetConstant(vreg, number_of_dex_registers, code_info);
return true;
case DexRegisterLocation::Kind::kNone:
return false;
default:
LOG(FATAL)
<< "Unexpected location kind"
<< DexRegisterLocation::PrettyDescriptor(
dex_register_map.GetLocationInternalKind(vreg, number_of_dex_registers, code_info));
UNREACHABLE();
}
}
bool StackVisitor::GetRegisterIfAccessible(uint32_t reg, VRegKind kind, uint32_t* val) const {
const bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
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::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();
}
if (cur_quick_frame_ != nullptr) {
DCHECK(context_ != nullptr); // You can't reliably read registers without a context.
DCHECK(m == GetMethod());
if (m->IsOptimized(sizeof(void*))) {
return GetVRegPairFromOptimizedCode(m, vreg, kind_lo, kind_hi, val);
} else {
return GetVRegPairFromQuickCode(m, vreg, kind_lo, kind_hi, val);
}
} else {
DCHECK(cur_shadow_frame_ != nullptr);
*val = cur_shadow_frame_->GetVRegLong(vreg);
return true;
}
}
bool StackVisitor::GetVRegPairFromQuickCode(ArtMethod* m, uint16_t vreg, VRegKind kind_lo,
VRegKind kind_hi, uint64_t* val) const {
const void* code_pointer = m->GetQuickOatCodePointer(sizeof(void*));
DCHECK(code_pointer != nullptr);
const VmapTable vmap_table(m->GetVmapTable(code_pointer, sizeof(void*)));
QuickMethodFrameInfo frame_info = m->GetQuickFrameInfo(code_pointer);
uint32_t vmap_offset_lo, vmap_offset_hi;
// TODO: IsInContext stops before spotting floating point registers.
if (vmap_table.IsInContext(vreg, kind_lo, &vmap_offset_lo) &&
vmap_table.IsInContext(vreg + 1, kind_hi, &vmap_offset_hi)) {
bool is_float = (kind_lo == kDoubleLoVReg);
uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
uint32_t reg_lo = vmap_table.ComputeRegister(spill_mask, vmap_offset_lo, kind_lo);
uint32_t reg_hi = vmap_table.ComputeRegister(spill_mask, vmap_offset_hi, kind_hi);
return GetRegisterPairIfAccessible(reg_lo, reg_hi, kind_lo, val);
} else {
const DexFile::CodeItem* code_item = m->GetCodeItem();
DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be null or how would we compile
// its instructions?
uint32_t* addr = GetVRegAddrFromQuickCode(
cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
*val = *reinterpret_cast<uint64_t*>(addr);
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) {
if (cur_quick_frame_ != nullptr) {
DCHECK(context_ != nullptr); // You can't reliably write registers without a context.
DCHECK(m == GetMethod());
if (m->IsOptimized(sizeof(void*))) {
return false;
} else {
return SetVRegFromQuickCode(m, vreg, new_value, kind);
}
} else {
cur_shadow_frame_->SetVReg(vreg, new_value);
return true;
}
}
bool StackVisitor::SetVRegFromQuickCode(ArtMethod* m, uint16_t vreg, uint32_t new_value,
VRegKind kind) {
DCHECK(context_ != nullptr); // You can't reliably write registers without a context.
DCHECK(m == GetMethod());
const void* code_pointer = m->GetQuickOatCodePointer(sizeof(void*));
DCHECK(code_pointer != nullptr);
const VmapTable vmap_table(m->GetVmapTable(code_pointer, sizeof(void*)));
QuickMethodFrameInfo frame_info = m->GetQuickFrameInfo(code_pointer);
uint32_t vmap_offset;
// TODO: IsInContext stops before spotting floating point registers.
if (vmap_table.IsInContext(vreg, kind, &vmap_offset)) {
bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
uint32_t reg = vmap_table.ComputeRegister(spill_mask, vmap_offset, kind);
return SetRegisterIfAccessible(reg, new_value, kind);
} else {
const DexFile::CodeItem* code_item = m->GetCodeItem();
DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be null or how would we compile
// its instructions?
uint32_t* addr = GetVRegAddrFromQuickCode(
cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
*addr = new_value;
return true;
}
}
bool StackVisitor::SetRegisterIfAccessible(uint32_t reg, uint32_t new_value, VRegKind kind) {
const bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
if (!IsAccessibleRegister(reg, is_float)) {
return false;
}
const bool target64 = Is64BitInstructionSet(kRuntimeISA);
// Create a new value that can hold both low 32 and high 32 bits, in
// case we are running 64 bits.
uintptr_t full_new_value = new_value;
// Deal with 32 or 64-bit wide registers in a way that builds on all targets.
if (target64) {
bool wide_lo = (kind == kLongLoVReg) || (kind == kDoubleLoVReg);
bool wide_hi = (kind == kLongHiVReg) || (kind == kDoubleHiVReg);
if (wide_lo || wide_hi) {
uintptr_t old_reg_val = GetRegister(reg, is_float);
uint64_t new_vreg_portion = static_cast<uint64_t>(new_value);
uint64_t old_reg_val_as_wide = static_cast<uint64_t>(old_reg_val);
uint64_t mask = 0xffffffff;
if (wide_lo) {
mask = mask << 32;
} else {
new_vreg_portion = new_vreg_portion << 32;
}
full_new_value = static_cast<uintptr_t>((old_reg_val_as_wide & mask) | new_vreg_portion);
}
}
SetRegister(reg, full_new_value, is_float);
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;
}
if (cur_quick_frame_ != nullptr) {
DCHECK(context_ != nullptr); // You can't reliably write registers without a context.
DCHECK(m == GetMethod());
if (m->IsOptimized(sizeof(void*))) {
return false;
} else {
return SetVRegPairFromQuickCode(m, vreg, new_value, kind_lo, kind_hi);
}
} else {
DCHECK(cur_shadow_frame_ != nullptr);
cur_shadow_frame_->SetVRegLong(vreg, new_value);
return true;
}
}
bool StackVisitor::SetVRegPairFromQuickCode(
ArtMethod* m, uint16_t vreg, uint64_t new_value, VRegKind kind_lo, VRegKind kind_hi) {
const void* code_pointer = m->GetQuickOatCodePointer(sizeof(void*));
DCHECK(code_pointer != nullptr);
const VmapTable vmap_table(m->GetVmapTable(code_pointer, sizeof(void*)));
QuickMethodFrameInfo frame_info = m->GetQuickFrameInfo(code_pointer);
uint32_t vmap_offset_lo, vmap_offset_hi;
// TODO: IsInContext stops before spotting floating point registers.
if (vmap_table.IsInContext(vreg, kind_lo, &vmap_offset_lo) &&
vmap_table.IsInContext(vreg + 1, kind_hi, &vmap_offset_hi)) {
bool is_float = (kind_lo == kDoubleLoVReg);
uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
uint32_t reg_lo = vmap_table.ComputeRegister(spill_mask, vmap_offset_lo, kind_lo);
uint32_t reg_hi = vmap_table.ComputeRegister(spill_mask, vmap_offset_hi, kind_hi);
return SetRegisterPairIfAccessible(reg_lo, reg_hi, new_value, is_float);
} else {
const DexFile::CodeItem* code_item = m->GetCodeItem();
DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be null or how would we compile
// its instructions?
uint32_t* addr = GetVRegAddrFromQuickCode(
cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
*reinterpret_cast<uint64_t*>(addr) = new_value;
return true;
}
}
bool StackVisitor::SetRegisterPairIfAccessible(uint32_t reg_lo, uint32_t reg_hi,
uint64_t new_value, bool is_float) {
if (!IsAccessibleRegister(reg_lo, is_float) || !IsAccessibleRegister(reg_hi, is_float)) {
return false;
}
uintptr_t new_value_lo = static_cast<uintptr_t>(new_value & 0xFFFFFFFF);
uintptr_t new_value_hi = static_cast<uintptr_t>(new_value >> 32);
bool target64 = Is64BitInstructionSet(kRuntimeISA);
// Deal with 32 or 64-bit wide registers in a way that builds on all targets.
if (target64) {
DCHECK_EQ(reg_lo, reg_hi);
SetRegister(reg_lo, new_value, is_float);
} else {
SetRegister(reg_lo, new_value_lo, is_float);
SetRegister(reg_hi, new_value_hi, is_float);
}
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);
}
void StackVisitor::SetGPR(uint32_t reg, uintptr_t value) {
DCHECK(cur_quick_frame_ != nullptr) << "This is a quick frame routine";
DCHECK(context_ != nullptr);
context_->SetGPR(reg, value);
}
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);
}
void StackVisitor::SetFPR(uint32_t reg, uintptr_t value) {
DCHECK(cur_quick_frame_ != nullptr) << "This is a quick frame routine";
DCHECK(context_ != nullptr);
context_->SetFPR(reg, value);
}
uintptr_t StackVisitor::GetReturnPc() const {
uint8_t* sp = reinterpret_cast<uint8_t*>(GetCurrentQuickFrame());
DCHECK(sp != nullptr);
uint8_t* pc_addr = sp + GetMethod()->GetReturnPcOffset().SizeValue();
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 + GetMethod()->GetReturnPcOffset().SizeValue();
*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_LOCKS_REQUIRED(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_LOCKS_REQUIRED(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);
}
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);
}
auto* runtime = Runtime::Current();
auto* la = runtime->GetLinearAlloc();
if (!la->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 auto* methods = &header.GetMethodsSection();
if (methods->Contains(reinterpret_cast<const uint8_t*>(method) - image_space->Begin())) {
in_image = true;
break;
}
}
}
CHECK(in_image) << PrettyMethod(method) << " not in linear alloc or image";
}
if (cur_quick_frame_ != nullptr) {
method->AssertPcIsWithinQuickCode(cur_quick_frame_pc_);
// Frame sanity.
size_t frame_size = method->GetFrameSizeInBytes();
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);
size_t return_pc_offset = method->GetReturnPcOffset().SizeValue();
CHECK_LT(return_pc_offset, frame_size);
}
}
}
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;
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;
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) {
SanityCheckFrame();
bool should_continue = VisitFrame();
if (UNLIKELY(!should_continue)) {
return;
}
if (context_ != nullptr) {
context_->FillCalleeSaves(*this);
}
size_t frame_size = method->GetFrameSizeInBytes();
// Compute PC for next stack frame from return PC.
size_t return_pc_offset = method->GetReturnPcOffset(frame_size).SizeValue();
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 if (instrumentation_frame.method_ != GetMethod()) {
LOG(FATAL) << "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.
CHECK(instrumentation_frame.frame_id_ == GetFrameId())
<< "Expected: " << instrumentation_frame.frame_id_
<< " Found: " << GetFrameId();
}
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
<< " optimized=" << method->IsOptimized(sizeof(void*))
<< " native=" << method->IsNative()
<< " entrypoints=" << method->GetEntryPointFromQuickCompiledCode()
<< "," << method->GetEntryPointFromJni()
<< "," << method->GetEntryPointFromInterpreter()
<< " 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_EQ(frame_size & (kStackAlignment - 1), 0U);
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 */;
}
}
} // namespace art