AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

[wasm] Store protected instructions in an OwnedVector

Browse Source 
We currently store the protected instructions per code object in a
{std::unique_ptr<std::vector<ProtectedInstructionData>>}. This wastes
memory, because it requires two heap allocations, plus the vector might
over-allocate (and it currently does, because it is filled dynamically
during compilation).
This CL changes that to store the protected instructions in an
{OwnedVector}. This requires one copy after generating the list of
{ProtectedInstructionData} in an {std::vector} during compilation, but
saves memory afterwards.

R=mstarzinger@chromium.org

Bug: chromium:856938
Change-Id: Ie290a17dc32f27fbbfe0c000a52297181c954550
Reviewed-on: https://chromium-review.googlesource.com/1116701
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54052}
This commit is contained in:
Clemens Hammacher 2018-06-27 12:26:30 +02:00 committed by Commit Bot
parent 9cd33e9eed
commit ce2d01bca3
11 changed files with 65 additions and 76 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/compiler/pipeline.cc
View File

@ -1051,7 +1051,7 @@ PipelineWasmCompilationJob::Status PipelineWasmCompilationJob::FinalizeJobImpl(
code_desc, code_generator->frame()->GetTotalFrameSlotCount(),
data_.wasm_function_index(), code_generator->GetSafepointTableOffset(),
code_generator->GetHandlerTableOffset(),
data_.wasm_compilation_data()->ReleaseProtectedInstructions(),
data_.wasm_compilation_data()->GetProtectedInstructions(),
code_generator->GetSourcePositionTable(), wasm::WasmCode::kTurbofan);
if (!code) return FAILED;

12
src/compiler/wasm-compiler.cc
View File

@ -4999,18 +4999,6 @@ MaybeHandle<Code> CompileCWasmEntry(Isolate* isolate, wasm::FunctionSig* sig) {
return code;
}
WasmCompilationData::WasmCompilationData(
wasm::RuntimeExceptionSupport runtime_exception_support)
: protected_instructions_(
new std::vector<trap_handler::ProtectedInstructionData>()),
runtime_exception_support_(runtime_exception_support) {}
void WasmCompilationData::AddProtectedInstruction(uint32_t instr_offset,
uint32_t landing_offset) {
protected_instructions_->emplace_back(
trap_handler::ProtectedInstructionData{instr_offset, landing_offset});
}
TurbofanWasmCompilationUnit::TurbofanWasmCompilationUnit(
wasm::WasmCompilationUnit* wasm_unit)
: wasm_unit_(wasm_unit),

17
src/compiler/wasm-compiler.h
View File

@ -52,13 +52,17 @@ namespace compiler {
class WasmCompilationData {
public:
explicit WasmCompilationData(
wasm::RuntimeExceptionSupport runtime_exception_support);
wasm::RuntimeExceptionSupport runtime_exception_support)
: runtime_exception_support_(runtime_exception_support) {}
void AddProtectedInstruction(uint32_t instr_offset, uint32_t landing_offset);
void AddProtectedInstruction(uint32_t instr_offset, uint32_t landing_offset) {
protected_instructions_.push_back({instr_offset, landing_offset});
}
std::unique_ptr<std::vector<trap_handler::ProtectedInstructionData>>
ReleaseProtectedInstructions() {
return std::move(protected_instructions_);
OwnedVector<trap_handler::ProtectedInstructionData>
GetProtectedInstructions() {
return OwnedVector<trap_handler::ProtectedInstructionData>::Of(
protected_instructions_);
}
wasm::RuntimeExceptionSupport runtime_exception_support() const {
@ -66,8 +70,7 @@ class WasmCompilationData {
}
private:
std::unique_ptr<std::vector<trap_handler::ProtectedInstructionData>>
protected_instructions_;
std::vector<trap_handler::ProtectedInstructionData> protected_instructions_;
// See ModuleEnv::runtime_exception_support_.
wasm::RuntimeExceptionSupport runtime_exception_support_;

3
src/source-position-table.cc
View File

@ -176,8 +176,7 @@ OwnedVector<byte> SourcePositionTableBuilder::ToSourcePositionTableVector() {
if (bytes_.empty()) return OwnedVector<byte>();
DCHECK(!Omit());
OwnedVector<byte> table = OwnedVector<byte>::New(bytes_.size());
MemCopy(table.start(), bytes_.data(), bytes_.size());
OwnedVector<byte> table = OwnedVector<byte>::Of(bytes_);
#ifdef ENABLE_SLOW_DCHECKS
// Brute force testing: Record all positions and decode

18
src/vector.h
View File

@ -5,8 +5,9 @@
#ifndef V8_VECTOR_H_
#define V8_VECTOR_H_
#include <string.h>
#include <algorithm>
#include <cstring>
#include <iterator>
#include "src/allocation.h"
#include "src/checks.h"
@ -210,9 +211,24 @@ class OwnedVector {
// Allocates a new vector of the specified size via the default allocator.
static OwnedVector<T> New(size_t size) {
if (size == 0) return {};
return OwnedVector<T>(std::unique_ptr<T[]>(new T[size]), size);
}
// Allocates a new vector containing the specified collection of values.
// {Iterator} is the common type of {std::begin} and {std::end} called on a
// {const U&}. This function is only instantiable if that type exists.
template <typename U, typename Iterator = typename std::common_type<
decltype(std::begin(std::declval<const U&>())),
decltype(std::end(std::declval<const U&>()))>::type>
static OwnedVector<T> Of(const U& collection) {
Iterator begin = std::begin(collection);
Iterator end = std::end(collection);
OwnedVector<T> vec = New(std::distance(begin, end));
std::copy(begin, end, vec.start());
return vec;
}
private:
std::unique_ptr<T[]> data_;
size_t length_ = 0;

14
src/wasm/baseline/liftoff-compiler.cc
View File

@ -1830,13 +1830,11 @@ bool LiftoffCompilationUnit::ExecuteCompilation() {
compiler::GetWasmCallDescriptor(&zone, wasm_unit_->func_body_.sig);
base::Optional<TimedHistogramScope> liftoff_compile_time_scope(
base::in_place, wasm_unit_->counters_->liftoff_compile_time());
DCHECK(!protected_instructions_);
protected_instructions_.reset(
new std::vector<trap_handler::ProtectedInstructionData>());
DCHECK(protected_instructions_.empty());
wasm::WasmFullDecoder<wasm::Decoder::kValidate, wasm::LiftoffCompiler>
decoder(&zone, module, wasm_unit_->func_body_, &asm_, call_descriptor,
wasm_unit_->env_, &source_position_table_builder_,
protected_instructions_.get(), &zone);
&protected_instructions_, &zone);
decoder.Decode();
liftoff_compile_time_scope.reset();
if (!decoder.interface().ok()) {
@ -1861,7 +1859,7 @@ bool LiftoffCompilationUnit::ExecuteCompilation() {
// Record the memory cost this unit places on the system until
// it is finalized.
wasm_unit_->memory_cost_ =
asm_.pc_offset() + protected_instructions_->size() *
asm_.pc_offset() + protected_instructions_.size() *
sizeof(trap_handler::ProtectedInstructionData);
safepoint_table_offset_ = decoder.interface().GetSafepointTableOffset();
@ -1876,10 +1874,12 @@ wasm::WasmCode* LiftoffCompilationUnit::FinishCompilation(
OwnedVector<byte> source_positions =
source_position_table_builder_.ToSourcePositionTableVector();
auto protected_instructions_copy =
OwnedVector<trap_handler::ProtectedInstructionData>::Of(
protected_instructions_);
wasm::WasmCode* code = wasm_unit_->native_module_->AddCode(
desc, asm_.GetTotalFrameSlotCount(), wasm_unit_->func_index_,
safepoint_table_offset_, 0, std::move(protected_instructions_),
safepoint_table_offset_, 0, std::move(protected_instructions_copy),
std::move(source_positions), wasm::WasmCode::kLiftoff);
return code;

3
src/wasm/baseline/liftoff-compiler.h
View File

@ -29,8 +29,7 @@ class LiftoffCompilationUnit final {
wasm::LiftoffAssembler asm_;
int safepoint_table_offset_;
SourcePositionTableBuilder source_position_table_builder_;
std::unique_ptr<std::vector<trap_handler::ProtectedInstructionData>>
protected_instructions_;
std::vector<trap_handler::ProtectedInstructionData> protected_instructions_;
DISALLOW_COPY_AND_ASSIGN(LiftoffCompilationUnit);
};

10
src/wasm/wasm-code-manager.cc
View File

@ -131,7 +131,7 @@ void WasmCode::RegisterTrapHandlerData() {
size_t size = instructions().size();
const int index =
RegisterHandlerData(base, size, protected_instructions().size(),
protected_instructions().data());
protected_instructions().start());
// TODO(eholk): if index is negative, fail.
CHECK_LE(0, index);
@ -365,7 +365,7 @@ WasmCode* NativeModule::AddOwnedCode(
Maybe<uint32_t> index, WasmCode::Kind kind, size_t constant_pool_offset,
uint32_t stack_slots, size_t safepoint_table_offset,
size_t handler_table_offset,
std::unique_ptr<ProtectedInstructions> protected_instructions,
OwnedVector<trap_handler::ProtectedInstructionData> protected_instructions,
WasmCode::Tier tier, WasmCode::FlushICache flush_icache) {
// both allocation and insertion in owned_code_ happen in the same critical
// section, thus ensuring owned_code_'s elements are rarely if ever moved.
@ -464,8 +464,6 @@ WasmCode* NativeModule::AddAnonymousCode(Handle<Code> code,
source_pos.reset(new byte[source_pos_table->length()]);
source_pos_table->copy_out(0, source_pos.get(), source_pos_table->length());
}
std::unique_ptr<ProtectedInstructions> protected_instructions(
new ProtectedInstructions(0));
Vector<const byte> orig_instructions(
reinterpret_cast<byte*>(code->InstructionStart()),
static_cast<size_t>(code->InstructionSize()));
@ -484,7 +482,7 @@ WasmCode* NativeModule::AddAnonymousCode(Handle<Code> code,
stack_slots, // stack_slots
safepoint_table_offset, // safepoint_table_offset
code->handler_table_offset(), // handler_table_offset
std::move(protected_instructions), // protected_instructions
{}, // protected_instructions
WasmCode::kOther, // kind
WasmCode::kNoFlushICache); // flush_icache
@ -521,7 +519,7 @@ WasmCode* NativeModule::AddAnonymousCode(Handle<Code> code,
WasmCode* NativeModule::AddCode(
const CodeDesc& desc, uint32_t frame_slots, uint32_t index,
size_t safepoint_table_offset, size_t handler_table_offset,
std::unique_ptr<ProtectedInstructions> protected_instructions,
OwnedVector<trap_handler::ProtectedInstructionData> protected_instructions,
OwnedVector<byte> source_pos_table, WasmCode::Tier tier) {
std::unique_ptr<byte[]> reloc_info;
if (desc.reloc_size) {

23
src/wasm/wasm-code-manager.h
View File

@ -86,9 +86,6 @@ class V8_EXPORT_PRIVATE DisjointAllocationPool final {
DISALLOW_COPY_AND_ASSIGN(DisjointAllocationPool)
};
using ProtectedInstructions =
std::vector<trap_handler::ProtectedInstructionData>;
class V8_EXPORT_PRIVATE WasmCode final {
public:
enum Kind {
@ -144,11 +141,9 @@ class V8_EXPORT_PRIVATE WasmCode final {
pc < reinterpret_cast<Address>(instructions_.end());
}
const ProtectedInstructions& protected_instructions() const {
// TODO(mstarzinger): Code that doesn't have trapping instruction should
// not be required to have this vector, make it possible to be null.
DCHECK_NOT_NULL(protected_instructions_);
return *protected_instructions_.get();
Vector<trap_handler::ProtectedInstructionData> protected_instructions()
const {
return protected_instructions_.as_vector();
}
void Validate() const;
@ -177,7 +172,8 @@ class V8_EXPORT_PRIVATE WasmCode final {
Maybe<uint32_t> index, Kind kind, size_t constant_pool_offset,
uint32_t stack_slots, size_t safepoint_table_offset,
size_t handler_table_offset,
std::unique_ptr<ProtectedInstructions> protected_instructions,
OwnedVector<trap_handler::ProtectedInstructionData>
protected_instructions,
Tier tier)
: instructions_(instructions),
reloc_info_(std::move(reloc_info)),
@ -225,7 +221,7 @@ class V8_EXPORT_PRIVATE WasmCode final {
size_t safepoint_table_offset_ = 0;
size_t handler_table_offset_ = 0;
intptr_t trap_handler_index_ = -1;
std::unique_ptr<ProtectedInstructions> protected_instructions_;
OwnedVector<trap_handler::ProtectedInstructionData> protected_instructions_;
Tier tier_;
DISALLOW_COPY_AND_ASSIGN(WasmCode);
@ -238,7 +234,8 @@ class V8_EXPORT_PRIVATE NativeModule final {
public:
WasmCode* AddCode(const CodeDesc& desc, uint32_t frame_count, uint32_t index,
size_t safepoint_table_offset, size_t handler_table_offset,
std::unique_ptr<ProtectedInstructions>,
OwnedVector<trap_handler::ProtectedInstructionData>
protected_instructions,
OwnedVector<byte> source_position_table,
WasmCode::Tier tier);
@ -361,8 +358,8 @@ class V8_EXPORT_PRIVATE NativeModule final {
WasmCode::Kind kind, size_t constant_pool_offset,
uint32_t stack_slots, size_t safepoint_table_offset,
size_t handler_table_offset,
std::unique_ptr<ProtectedInstructions>, WasmCode::Tier,
WasmCode::FlushICache);
OwnedVector<trap_handler::ProtectedInstructionData>,
WasmCode::Tier, WasmCode::FlushICache);
WasmCode* CreateEmptyJumpTable(uint32_t num_wasm_functions);

18
src/wasm/wasm-serialization.cc
View File

@ -301,10 +301,7 @@ void NativeModuleSerializer::WriteCode(const WasmCode* code, Writer* writer) {
// Write the reloc info, source positions, and protected code.
writer->WriteVector(code->reloc_info());
writer->WriteVector(code->source_positions());
writer->WriteVector(
{reinterpret_cast<const byte*>(code->protected_instructions().data()),
sizeof(trap_handler::ProtectedInstructionData) *
code->protected_instructions().size()});
writer->WriteVector(Vector<byte>::cast(code->protected_instructions()));
#if V8_TARGET_ARCH_MIPS || V8_TARGET_ARCH_MIPS64 || V8_TARGET_ARCH_ARM
// On platforms that don't support misaligned word stores, copy to an aligned
// buffer if necessary so we can relocate the serialized code.
@ -458,15 +455,10 @@ bool NativeModuleDeserializer::ReadCode(uint32_t fn_index, Reader* reader) {
source_pos.reset(new byte[source_position_size]);
reader->ReadVector({source_pos.get(), source_position_size});
}
std::unique_ptr<ProtectedInstructions> protected_instructions(
new ProtectedInstructions(protected_instructions_size));
if (protected_instructions_size > 0) {
size_t size = sizeof(trap_handler::ProtectedInstructionData) *
protected_instructions->size();
Vector<byte> data(reinterpret_cast<byte*>(protected_instructions->data()),
size);
reader->ReadVector(data);
}
auto protected_instructions =
OwnedVector<trap_handler::ProtectedInstructionData>::New(
protected_instructions_size);
reader->ReadVector(Vector<byte>::cast(protected_instructions.as_vector()));
WasmCode* ret = native_module_->AddOwnedCode(
code_buffer, std::move(reloc_info), reloc_size, std::move(source_pos),
source_position_size, Just(fn_index), WasmCode::kFunction,

5
test/cctest/wasm/test-run-wasm.cc
View File

@ -3438,10 +3438,7 @@ TEST(Liftoff_tier_up) {
memcpy(buffer.get(), sub_code->instructions().start(), sub_size);
desc.buffer = buffer.get();
desc.instr_size = static_cast<int>(sub_size);
std::unique_ptr<ProtectedInstructions> protected_instructions(
new ProtectedInstructions(sub_code->protected_instructions()));
native_module->AddCode(desc, 0, add.function_index(), 0, 0,
std::move(protected_instructions),
native_module->AddCode(desc, 0, add.function_index(), 0, 0, {},
OwnedVector<byte>(), WasmCode::kOther);
// Second run should now execute {sub}.