/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "quick_exception_handler.h"
#include "arch/context.h"
#include "art_method-inl.h"
#include "base/enums.h"
#include "base/logging.h" // For VLOG_IS_ON.
#include "base/systrace.h"
#include "dex/dex_file_types.h"
#include "dex/dex_instruction.h"
#include "entrypoints/entrypoint_utils.h"
#include "entrypoints/quick/quick_entrypoints_enum.h"
#include "entrypoints/runtime_asm_entrypoints.h"
#include "handle_scope-inl.h"
#include "interpreter/shadow_frame-inl.h"
#include "jit/jit.h"
#include "jit/jit_code_cache.h"
#include "mirror/class-inl.h"
#include "mirror/class_loader.h"
#include "mirror/throwable.h"
#include "oat_quick_method_header.h"
#include "stack.h"
#include "stack_map.h"
namespace art {
static constexpr bool kDebugExceptionDelivery = false;
static constexpr size_t kInvalidFrameDepth = 0xffffffff;
QuickExceptionHandler::QuickExceptionHandler(Thread* self, bool is_deoptimization)
: self_(self),
context_(self->GetLongJumpContext()),
is_deoptimization_(is_deoptimization),
method_tracing_active_(is_deoptimization ||
Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled()),
handler_quick_frame_(nullptr),
handler_quick_frame_pc_(0),
handler_method_header_(nullptr),
handler_quick_arg0_(0),
handler_method_(nullptr),
handler_dex_pc_(0),
clear_exception_(false),
handler_frame_depth_(kInvalidFrameDepth),
full_fragment_done_(false) {}
// Finds catch handler.
class CatchBlockStackVisitor final : public StackVisitor {
public:
CatchBlockStackVisitor(Thread* self,
Context* context,
Handle<mirror::Throwable>* exception,
QuickExceptionHandler* exception_handler,
uint32_t skip_frames)
REQUIRES_SHARED(Locks::mutator_lock_)
: StackVisitor(self, context, StackVisitor::StackWalkKind::kIncludeInlinedFrames),
exception_(exception),
exception_handler_(exception_handler),
skip_frames_(skip_frames) {
}
bool VisitFrame() override REQUIRES_SHARED(Locks::mutator_lock_) {
ArtMethod* method = GetMethod();
exception_handler_->SetHandlerFrameDepth(GetFrameDepth());
if (method == nullptr) {
DCHECK_EQ(skip_frames_, 0u)
<< "We tried to skip an upcall! We should have returned to the upcall to finish delivery";
// This is the upcall, we remember the frame and last pc so that we may long jump to them.
exception_handler_->SetHandlerQuickFramePc(GetCurrentQuickFramePc());
exception_handler_->SetHandlerQuickFrame(GetCurrentQuickFrame());
exception_handler_->SetHandlerMethodHeader(GetCurrentOatQuickMethodHeader());
uint32_t next_dex_pc;
ArtMethod* next_art_method;
bool has_next = GetNextMethodAndDexPc(&next_art_method, &next_dex_pc);
// Report the method that did the down call as the handler.
exception_handler_->SetHandlerDexPc(next_dex_pc);
exception_handler_->SetHandlerMethod(next_art_method);
if (!has_next) {
// No next method? Check exception handler is set up for the unhandled exception handler
// case.
DCHECK_EQ(0U, exception_handler_->GetHandlerDexPc());
DCHECK(nullptr == exception_handler_->GetHandlerMethod());
}
return false; // End stack walk.
}
if (skip_frames_ != 0) {
skip_frames_--;
return true;
}
if (method->IsRuntimeMethod()) {
// Ignore callee save method.
DCHECK(method->IsCalleeSaveMethod());
return true;
}
return HandleTryItems(method);
}
private:
bool HandleTryItems(ArtMethod* method)
REQUIRES_SHARED(Locks::mutator_lock_) {
uint32_t dex_pc = dex::kDexNoIndex;
if (!method->IsNative()) {
dex_pc = GetDexPc();
}
if (dex_pc != dex::kDexNoIndex) {
bool clear_exception = false;
StackHandleScope<1> hs(GetThread());
Handle<mirror::Class> to_find(hs.NewHandle((*exception_)->GetClass()));
uint32_t found_dex_pc = method->FindCatchBlock(to_find, dex_pc, &clear_exception);
exception_handler_->SetClearException(clear_exception);
if (found_dex_pc != dex::kDexNoIndex) {
exception_handler_->SetHandlerMethod(method);
exception_handler_->SetHandlerDexPc(found_dex_pc);
exception_handler_->SetHandlerQuickFramePc(
GetCurrentOatQuickMethodHeader()->ToNativeQuickPc(
method, found_dex_pc, /* is_for_catch_handler= */ true));
exception_handler_->SetHandlerQuickFrame(GetCurrentQuickFrame());
exception_handler_->SetHandlerMethodHeader(GetCurrentOatQuickMethodHeader());
return false; // End stack walk.
} else if (UNLIKELY(GetThread()->HasDebuggerShadowFrames())) {
// We are going to unwind this frame. Did we prepare a shadow frame for debugging?
size_t frame_id = GetFrameId();
ShadowFrame* frame = GetThread()->FindDebuggerShadowFrame(frame_id);
if (frame != nullptr) {
// We will not execute this shadow frame so we can safely deallocate it.
GetThread()->RemoveDebuggerShadowFrameMapping(frame_id);
ShadowFrame::DeleteDeoptimizedFrame(frame);
}
}
}
return true; // Continue stack walk.
}
// The exception we're looking for the catch block of.
Handle<mirror::Throwable>* exception_;
// The quick exception handler we're visiting for.
QuickExceptionHandler* const exception_handler_;
// The number of frames to skip searching for catches in.
uint32_t skip_frames_;
DISALLOW_COPY_AND_ASSIGN(CatchBlockStackVisitor);
};
static size_t GetInstrumentationFramesToPop(Thread* self, size_t frame_depth)
REQUIRES_SHARED(Locks::mutator_lock_) {
CHECK_NE(frame_depth, kInvalidFrameDepth);
size_t instrumentation_frames_to_pop = 0;
StackVisitor::WalkStack(
[&](art::StackVisitor* stack_visitor) REQUIRES_SHARED(Locks::mutator_lock_) {
size_t current_frame_depth = stack_visitor->GetFrameDepth();
if (current_frame_depth < frame_depth) {
CHECK(stack_visitor->GetMethod() != nullptr);
if (UNLIKELY(reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc()) ==
stack_visitor->GetReturnPc())) {
if (!stack_visitor->IsInInlinedFrame()) {
// We do not count inlined frames, because we do not instrument them. The reason we
// include them in the stack walking is the check against `frame_depth_`, which is
// given to us by a visitor that visits inlined frames.
++instrumentation_frames_to_pop;
}
}
return true;
}
// We reached the frame of the catch handler or the upcall.
return false;
},
self,
/* context= */ nullptr,
art::StackVisitor::StackWalkKind::kIncludeInlinedFrames,
/* check_suspended */ true,
/* include_transitions */ true);
return instrumentation_frames_to_pop;
}
// Finds the appropriate exception catch after calling all method exit instrumentation functions.
// Note that this might change the exception being thrown.
void QuickExceptionHandler::FindCatch(ObjPtr<mirror::Throwable> exception) {
DCHECK(!is_deoptimization_);
instrumentation::InstrumentationStackPopper popper(self_);
// The number of total frames we have so far popped.
uint32_t already_popped = 0;
bool popped_to_top = true;
StackHandleScope<1> hs(self_);
MutableHandle<mirror::Throwable> exception_ref(hs.NewHandle(exception));
// Sending the instrumentation events (done by the InstrumentationStackPopper) can cause new
// exceptions to be thrown which will override the current exception. Therefore we need to perform
// the search for a catch in a loop until we have successfully popped all the way to a catch or
// the top of the stack.
do {
if (kDebugExceptionDelivery) {
ObjPtr<mirror::String> msg = exception_ref->GetDetailMessage();
std::string str_msg(msg != nullptr ? msg->ToModifiedUtf8() : "");
self_->DumpStack(LOG_STREAM(INFO) << "Delivering exception: " << exception_ref->PrettyTypeOf()
<< ": " << str_msg << "\n");
}
// Walk the stack to find catch handler.
CatchBlockStackVisitor visitor(self_, context_,
&exception_ref,
this,
/*skip_frames=*/already_popped);
visitor.WalkStack(true);
uint32_t new_pop_count = handler_frame_depth_;
DCHECK_GE(new_pop_count, already_popped);
already_popped = new_pop_count;
// Figure out how many of those frames have instrumentation we need to remove (Should be the
// exact same as number of new_pop_count if there aren't inlined frames).
size_t instrumentation_frames_to_pop =
GetInstrumentationFramesToPop(self_, handler_frame_depth_);
if (kDebugExceptionDelivery) {
if (*handler_quick_frame_ == nullptr) {
LOG(INFO) << "Handler is upcall";
}
if (handler_method_ != nullptr) {
const DexFile* dex_file = handler_method_->GetDexFile();
int line_number = annotations::GetLineNumFromPC(dex_file, handler_method_, handler_dex_pc_);
LOG(INFO) << "Handler: " << handler_method_->PrettyMethod() << " (line: "
<< line_number << ")";
}
LOG(INFO) << "Will attempt to pop " << instrumentation_frames_to_pop
<< " off of the instrumentation stack";
}
// Exception was cleared as part of delivery.
DCHECK(!self_->IsExceptionPending());
// If the handler is in optimized code, we need to set the catch environment.
if (*handler_quick_frame_ != nullptr &&
handler_method_header_ != nullptr &&
handler_method_header_->IsOptimized()) {
SetCatchEnvironmentForOptimizedHandler(&visitor);
}
popped_to_top = popper.PopFramesTo(instrumentation_frames_to_pop, exception_ref);
} while (!popped_to_top);
if (!clear_exception_) {
// Put exception back in root set with clear throw location.
self_->SetException(exception_ref.Get());
}
}
static VRegKind ToVRegKind(DexRegisterLocation::Kind kind) {
// Slightly hacky since we cannot map DexRegisterLocationKind and VRegKind
// one to one. However, StackVisitor::GetVRegFromOptimizedCode only needs to
// distinguish between core/FPU registers and low/high bits on 64-bit.
switch (kind) {
case DexRegisterLocation::Kind::kConstant:
case DexRegisterLocation::Kind::kInStack:
// VRegKind is ignored.
return VRegKind::kUndefined;
case DexRegisterLocation::Kind::kInRegister:
// Selects core register. For 64-bit registers, selects low 32 bits.
return VRegKind::kLongLoVReg;
case DexRegisterLocation::Kind::kInRegisterHigh:
// Selects core register. For 64-bit registers, selects high 32 bits.
return VRegKind::kLongHiVReg;
case DexRegisterLocation::Kind::kInFpuRegister:
// Selects FPU register. For 64-bit registers, selects low 32 bits.
return VRegKind::kDoubleLoVReg;
case DexRegisterLocation::Kind::kInFpuRegisterHigh:
// Selects FPU register. For 64-bit registers, selects high 32 bits.
return VRegKind::kDoubleHiVReg;
default:
LOG(FATAL) << "Unexpected vreg location " << kind;
UNREACHABLE();
}
}
void QuickExceptionHandler::SetCatchEnvironmentForOptimizedHandler(StackVisitor* stack_visitor) {
DCHECK(!is_deoptimization_);
DCHECK(*handler_quick_frame_ != nullptr) << "Method should not be called on upcall exceptions";
DCHECK(handler_method_ != nullptr && handler_method_header_->IsOptimized());
if (kDebugExceptionDelivery) {
self_->DumpStack(LOG_STREAM(INFO) << "Setting catch phis: ");
}
CodeItemDataAccessor accessor(handler_method_->DexInstructionData());
const size_t number_of_vregs = accessor.RegistersSize();
CodeInfo code_info(handler_method_header_);
// Find stack map of the catch block.
StackMap catch_stack_map = code_info.GetCatchStackMapForDexPc(GetHandlerDexPc());
DCHECK(catch_stack_map.IsValid());
DexRegisterMap catch_vreg_map = code_info.GetDexRegisterMapOf(catch_stack_map);
if (!catch_vreg_map.HasAnyLiveDexRegisters()) {
return;
}
DCHECK_EQ(catch_vreg_map.size(), number_of_vregs);
// Find stack map of the throwing instruction.
StackMap throw_stack_map =
code_info.GetStackMapForNativePcOffset(stack_visitor->GetNativePcOffset());
DCHECK(throw_stack_map.IsValid());
DexRegisterMap throw_vreg_map = code_info.GetDexRegisterMapOf(throw_stack_map);
DCHECK_EQ(throw_vreg_map.size(), number_of_vregs);
// Copy values between them.
for (uint16_t vreg = 0; vreg < number_of_vregs; ++vreg) {
DexRegisterLocation::Kind catch_location = catch_vreg_map[vreg].GetKind();
if (catch_location == DexRegisterLocation::Kind::kNone) {
continue;
}
DCHECK(catch_location == DexRegisterLocation::Kind::kInStack);
// Get vreg value from its current location.
uint32_t vreg_value;
VRegKind vreg_kind = ToVRegKind(throw_vreg_map[vreg].GetKind());
bool get_vreg_success = stack_visitor->GetVReg(stack_visitor->GetMethod(),
vreg,
vreg_kind,
&vreg_value);
CHECK(get_vreg_success) << "VReg " << vreg << " was optimized out ("
<< "method=" << ArtMethod::PrettyMethod(stack_visitor->GetMethod())
<< ", dex_pc=" << stack_visitor->GetDexPc() << ", "
<< "native_pc_offset=" << stack_visitor->GetNativePcOffset() << ")";
// Copy value to the catch phi's stack slot.
int32_t slot_offset = catch_vreg_map[vreg].GetStackOffsetInBytes();
ArtMethod** frame_top = stack_visitor->GetCurrentQuickFrame();
uint8_t* slot_address = reinterpret_cast<uint8_t*>(frame_top) + slot_offset;
uint32_t* slot_ptr = reinterpret_cast<uint32_t*>(slot_address);
*slot_ptr = vreg_value;
}
}
// Prepares deoptimization.
class DeoptimizeStackVisitor final : public StackVisitor {
public:
DeoptimizeStackVisitor(Thread* self,
Context* context,
QuickExceptionHandler* exception_handler,
bool single_frame)
REQUIRES_SHARED(Locks::mutator_lock_)
: StackVisitor(self, context, StackVisitor::StackWalkKind::kIncludeInlinedFrames),
exception_handler_(exception_handler),
prev_shadow_frame_(nullptr),
stacked_shadow_frame_pushed_(false),
single_frame_deopt_(single_frame),
single_frame_done_(false),
single_frame_deopt_method_(nullptr),
single_frame_deopt_quick_method_header_(nullptr),
callee_method_(nullptr) {
}
ArtMethod* GetSingleFrameDeoptMethod() const {
return single_frame_deopt_method_;
}
const OatQuickMethodHeader* GetSingleFrameDeoptQuickMethodHeader() const {
return single_frame_deopt_quick_method_header_;
}
void FinishStackWalk() REQUIRES_SHARED(Locks::mutator_lock_) {
// This is the upcall, or the next full frame in single-frame deopt, or the
// code isn't deoptimizeable. We remember the frame and last pc so that we
// may long jump to them.
exception_handler_->SetHandlerQuickFramePc(GetCurrentQuickFramePc());
exception_handler_->SetHandlerQuickFrame(GetCurrentQuickFrame());
exception_handler_->SetHandlerMethodHeader(GetCurrentOatQuickMethodHeader());
if (!stacked_shadow_frame_pushed_) {
// In case there is no deoptimized shadow frame for this upcall, we still
// need to push a nullptr to the stack since there is always a matching pop after
// the long jump.
GetThread()->PushStackedShadowFrame(nullptr,
StackedShadowFrameType::kDeoptimizationShadowFrame);
stacked_shadow_frame_pushed_ = true;
}
if (GetMethod() == nullptr) {
exception_handler_->SetFullFragmentDone(true);
} else {
CHECK(callee_method_ != nullptr) << GetMethod()->PrettyMethod(false);
exception_handler_->SetHandlerQuickArg0(reinterpret_cast<uintptr_t>(callee_method_));
}
}
bool VisitFrame() override REQUIRES_SHARED(Locks::mutator_lock_) {
exception_handler_->SetHandlerFrameDepth(GetFrameDepth());
ArtMethod* method = GetMethod();
VLOG(deopt) << "Deoptimizing stack: depth: " << GetFrameDepth()
<< " at method " << ArtMethod::PrettyMethod(method);
if (method == nullptr || single_frame_done_) {
FinishStackWalk();
return false; // End stack walk.
} else if (method->IsRuntimeMethod()) {
// Ignore callee save method.
DCHECK(method->IsCalleeSaveMethod());
return true;
} else if (method->IsNative()) {
// If we return from JNI with a pending exception and want to deoptimize, we need to skip
// the native method.
// The top method is a runtime method, the native method comes next.
CHECK_EQ(GetFrameDepth(), 1U);
callee_method_ = method;
return true;
} else if (!single_frame_deopt_ &&
!Runtime::Current()->IsAsyncDeoptimizeable(GetCurrentQuickFramePc())) {
// We hit some code that's not deoptimizeable. However, Single-frame deoptimization triggered
// from compiled code is always allowed since HDeoptimize always saves the full environment.
LOG(WARNING) << "Got request to deoptimize un-deoptimizable method "
<< method->PrettyMethod();
FinishStackWalk();
return false; // End stack walk.
} else {
// Check if a shadow frame already exists for debugger's set-local-value purpose.
const size_t frame_id = GetFrameId();
ShadowFrame* new_frame = GetThread()->FindDebuggerShadowFrame(frame_id);
const bool* updated_vregs;
CodeItemDataAccessor accessor(method->DexInstructionData());
const size_t num_regs = accessor.RegistersSize();
if (new_frame == nullptr) {
new_frame = ShadowFrame::CreateDeoptimizedFrame(num_regs, nullptr, method, GetDexPc());
updated_vregs = nullptr;
} else {
updated_vregs = GetThread()->GetUpdatedVRegFlags(frame_id);
DCHECK(updated_vregs != nullptr);
}
HandleOptimizingDeoptimization(method, new_frame, updated_vregs);
if (updated_vregs != nullptr) {
// Calling Thread::RemoveDebuggerShadowFrameMapping will also delete the updated_vregs
// array so this must come after we processed the frame.
GetThread()->RemoveDebuggerShadowFrameMapping(frame_id);
DCHECK(GetThread()->FindDebuggerShadowFrame(frame_id) == nullptr);
}
if (prev_shadow_frame_ != nullptr) {
prev_shadow_frame_->SetLink(new_frame);
} else {
// Will be popped after the long jump after DeoptimizeStack(),
// right before interpreter::EnterInterpreterFromDeoptimize().
stacked_shadow_frame_pushed_ = true;
GetThread()->PushStackedShadowFrame(
new_frame, StackedShadowFrameType::kDeoptimizationShadowFrame);
}
prev_shadow_frame_ = new_frame;
if (single_frame_deopt_ && !IsInInlinedFrame()) {
// Single-frame deopt ends at the first non-inlined frame and needs to store that method.
single_frame_done_ = true;
single_frame_deopt_method_ = method;
single_frame_deopt_quick_method_header_ = GetCurrentOatQuickMethodHeader();
}
callee_method_ = method;
return true;
}
}
private:
void HandleOptimizingDeoptimization(ArtMethod* m,
ShadowFrame* new_frame,
const bool* updated_vregs)
REQUIRES_SHARED(Locks::mutator_lock_) {
const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
CodeInfo code_info(method_header);
uintptr_t native_pc_offset = method_header->NativeQuickPcOffset(GetCurrentQuickFramePc());
StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset);
CodeItemDataAccessor accessor(m->DexInstructionData());
const size_t number_of_vregs = accessor.RegistersSize();
uint32_t register_mask = code_info.GetRegisterMaskOf(stack_map);
BitMemoryRegion stack_mask = code_info.GetStackMaskOf(stack_map);
DexRegisterMap vreg_map = IsInInlinedFrame()
? code_info.GetInlineDexRegisterMapOf(stack_map, GetCurrentInlinedFrame())
: code_info.GetDexRegisterMapOf(stack_map);
if (vreg_map.empty()) {
return;
}
DCHECK_EQ(vreg_map.size(), number_of_vregs);
for (uint16_t vreg = 0; vreg < number_of_vregs; ++vreg) {
if (updated_vregs != nullptr && updated_vregs[vreg]) {
// Keep the value set by debugger.
continue;
}
DexRegisterLocation::Kind location = vreg_map[vreg].GetKind();
static constexpr uint32_t kDeadValue = 0xEBADDE09;
uint32_t value = kDeadValue;
bool is_reference = false;
switch (location) {
case DexRegisterLocation::Kind::kInStack: {
const int32_t offset = vreg_map[vreg].GetStackOffsetInBytes();
const uint8_t* addr = reinterpret_cast<const uint8_t*>(GetCurrentQuickFrame()) + offset;
value = *reinterpret_cast<const uint32_t*>(addr);
uint32_t bit = (offset >> 2);
if (bit < stack_mask.size_in_bits() && stack_mask.LoadBit(bit)) {
is_reference = true;
}
break;
}
case DexRegisterLocation::Kind::kInRegister:
case DexRegisterLocation::Kind::kInRegisterHigh:
case DexRegisterLocation::Kind::kInFpuRegister:
case DexRegisterLocation::Kind::kInFpuRegisterHigh: {
uint32_t reg = vreg_map[vreg].GetMachineRegister();
bool result = GetRegisterIfAccessible(reg, ToVRegKind(location), &value);
CHECK(result);
if (location == DexRegisterLocation::Kind::kInRegister) {
if (((1u << reg) & register_mask) != 0) {
is_reference = true;
}
}
break;
}
case DexRegisterLocation::Kind::kConstant: {
value = vreg_map[vreg].GetConstant();
if (value == 0) {
// Make it a reference for extra safety.
is_reference = true;
}
break;
}
case DexRegisterLocation::Kind::kNone: {
break;
}
default: {
LOG(FATAL) << "Unexpected location kind " << vreg_map[vreg].GetKind();
UNREACHABLE();
}
}
if (is_reference) {
new_frame->SetVRegReference(vreg, reinterpret_cast<mirror::Object*>(value));
} else {
new_frame->SetVReg(vreg, value);
}
}
}
static VRegKind GetVRegKind(uint16_t reg, const std::vector<int32_t>& kinds) {
return static_cast<VRegKind>(kinds[reg * 2]);
}
QuickExceptionHandler* const exception_handler_;
ShadowFrame* prev_shadow_frame_;
bool stacked_shadow_frame_pushed_;
const bool single_frame_deopt_;
bool single_frame_done_;
ArtMethod* single_frame_deopt_method_;
const OatQuickMethodHeader* single_frame_deopt_quick_method_header_;
ArtMethod* callee_method_;
DISALLOW_COPY_AND_ASSIGN(DeoptimizeStackVisitor);
};
void QuickExceptionHandler::PrepareForLongJumpToInvokeStubOrInterpreterBridge() {
if (full_fragment_done_) {
// Restore deoptimization exception. When returning from the invoke stub,
// ArtMethod::Invoke() will see the special exception to know deoptimization
// is needed.
self_->SetException(Thread::GetDeoptimizationException());
} else {
// PC needs to be of the quick-to-interpreter bridge.
int32_t offset;
offset = GetThreadOffset<kRuntimePointerSize>(kQuickQuickToInterpreterBridge).Int32Value();
handler_quick_frame_pc_ = *reinterpret_cast<uintptr_t*>(
reinterpret_cast<uint8_t*>(self_) + offset);
}
}
void QuickExceptionHandler::DeoptimizeStack() {
DCHECK(is_deoptimization_);
if (kDebugExceptionDelivery) {
self_->DumpStack(LOG_STREAM(INFO) << "Deoptimizing: ");
}
DeoptimizeStackVisitor visitor(self_, context_, this, false);
visitor.WalkStack(true);
PrepareForLongJumpToInvokeStubOrInterpreterBridge();
}
void QuickExceptionHandler::DeoptimizeSingleFrame(DeoptimizationKind kind) {
DCHECK(is_deoptimization_);
DeoptimizeStackVisitor visitor(self_, context_, this, true);
visitor.WalkStack(true);
// Compiled code made an explicit deoptimization.
ArtMethod* deopt_method = visitor.GetSingleFrameDeoptMethod();
SCOPED_TRACE << "Deoptimizing "
<< deopt_method->PrettyMethod()
<< ": " << GetDeoptimizationKindName(kind);
DCHECK(deopt_method != nullptr);
if (VLOG_IS_ON(deopt) || kDebugExceptionDelivery) {
LOG(INFO) << "Single-frame deopting: "
<< deopt_method->PrettyMethod()
<< " due to "
<< GetDeoptimizationKindName(kind);
DumpFramesWithType(self_, /* details= */ true);
}
if (Runtime::Current()->UseJitCompilation()) {
Runtime::Current()->GetJit()->GetCodeCache()->InvalidateCompiledCodeFor(
deopt_method, visitor.GetSingleFrameDeoptQuickMethodHeader());
} else {
// Transfer the code to interpreter.
Runtime::Current()->GetInstrumentation()->UpdateMethodsCode(
deopt_method, GetQuickToInterpreterBridge());
}
PrepareForLongJumpToInvokeStubOrInterpreterBridge();
}
void QuickExceptionHandler::DeoptimizePartialFragmentFixup(uintptr_t return_pc) {
// At this point, the instrumentation stack has been updated. We need to install
// the real return pc on stack, in case instrumentation stub is stored there,
// so that the interpreter bridge code can return to the right place.
if (return_pc != 0) {
uintptr_t* pc_addr = reinterpret_cast<uintptr_t*>(handler_quick_frame_);
CHECK(pc_addr != nullptr);
pc_addr--;
*reinterpret_cast<uintptr_t*>(pc_addr) = return_pc;
}
// Architecture-dependent work. This is to get the LR right for x86 and x86-64.
if (kRuntimeISA == InstructionSet::kX86 || kRuntimeISA == InstructionSet::kX86_64) {
// On x86, the return address is on the stack, so just reuse it. Otherwise we would have to
// change how longjump works.
handler_quick_frame_ = reinterpret_cast<ArtMethod**>(
reinterpret_cast<uintptr_t>(handler_quick_frame_) - sizeof(void*));
}
}
uintptr_t QuickExceptionHandler::UpdateInstrumentationStack() {
DCHECK(is_deoptimization_) << "Non-deoptimization handlers should use FindCatch";
uintptr_t return_pc = 0;
if (method_tracing_active_) {
size_t instrumentation_frames_to_pop =
GetInstrumentationFramesToPop(self_, handler_frame_depth_);
instrumentation::Instrumentation* instrumentation = Runtime::Current()->GetInstrumentation();
return_pc = instrumentation->PopFramesForDeoptimization(self_, instrumentation_frames_to_pop);
}
return return_pc;
}
void QuickExceptionHandler::DoLongJump(bool smash_caller_saves) {
// Place context back on thread so it will be available when we continue.
self_->ReleaseLongJumpContext(context_);
context_->SetSP(reinterpret_cast<uintptr_t>(handler_quick_frame_));
CHECK_NE(handler_quick_frame_pc_, 0u);
context_->SetPC(handler_quick_frame_pc_);
context_->SetArg0(handler_quick_arg0_);
if (smash_caller_saves) {
context_->SmashCallerSaves();
}
context_->DoLongJump();
UNREACHABLE();
}
void QuickExceptionHandler::DumpFramesWithType(Thread* self, bool details) {
StackVisitor::WalkStack(
[&](const art::StackVisitor* stack_visitor) REQUIRES_SHARED(Locks::mutator_lock_) {
ArtMethod* method = stack_visitor->GetMethod();
if (details) {
LOG(INFO) << "|> pc = " << std::hex << stack_visitor->GetCurrentQuickFramePc();
LOG(INFO) << "|> addr = " << std::hex
<< reinterpret_cast<uintptr_t>(stack_visitor->GetCurrentQuickFrame());
if (stack_visitor->GetCurrentQuickFrame() != nullptr && method != nullptr) {
LOG(INFO) << "|> ret = " << std::hex << stack_visitor->GetReturnPc();
}
}
if (method == nullptr) {
// Transition, do go on, we want to unwind over bridges, all the way.
if (details) {
LOG(INFO) << "N <transition>";
}
return true;
} else if (method->IsRuntimeMethod()) {
if (details) {
LOG(INFO) << "R " << method->PrettyMethod(true);
}
return true;
} else {
bool is_shadow = stack_visitor->GetCurrentShadowFrame() != nullptr;
LOG(INFO) << (is_shadow ? "S" : "Q")
<< ((!is_shadow && stack_visitor->IsInInlinedFrame()) ? "i" : " ")
<< " "
<< method->PrettyMethod(true);
return true; // Go on.
}
},
self,
/* context= */ nullptr,
art::StackVisitor::StackWalkKind::kIncludeInlinedFrames);
}
} // namespace art