dart-lang/sdk
1
0
Fork 0
Code Issues Pull Requests Actions 2 Packages Projects Releases Wiki Activity
Files
45a46ca2b8833f62ecfb53f0a8cc63e1802132e1
sdk/runtime/vm/kernel_binary.h
T
Tess Strickland 45a46ca2b8 [vm] Add (S)LEB128 encoding/decoding to BaseWriteStream. 
Unlike cfc8e6de, this does _not_ replace the default variable length
encoding for {Read,Write}Streams, but insteads adds separate
{Read,Write}{S,}LEB128 methods to the appropriate classes. If we later
find the cause of the issues that led to the revert of cfc8e6de, it'll
be easy to switch over then.

Note that WriteLEB128 asserts that the value is non-negative if used
with a signed type (since negative values suggests that SLEB128 should
be used instead for minimal encoding).

Also removes the various other encoding and decoding methods for
(S)LEB128 across the codebase and changes those clients to use
{Read,Write}Streams instead.

Other cleanups:

* Various constant-related cleanups in datastream.h.

* Adds DART_FORCE_INLINE to ReadStream::ReadByte and uses it in the
  default variable length decoding methods for retrieving bytes
  from the stream instead of managing current_ by hand.

* Creates a canonical empty CompressedStackMaps instance and uses
  that instead of the null CompressedStackMaps instance in most cases.
  The only remaining (expected) use of the null CompressedStackMaps
  instance is for the global table in the object store when no global
  table exists (e.g., in JIT mode before any snapshotting).

* Moves CompressedStackMapsIterator from code_descriptors.h to an
  Iterator class within CompressedStackMaps in object.h (similar to
  PcDescriptors::Iterator), to limit friend declarations and because it
  conceptually makes more sense as part of CompressedStackMaps.

* Removed CompressedStackMaps::PayloadByte, since existing clients
  (CompressedStackMaps::Iterator, StackMapEntry in program_visitor.cc)
  are better served by just operating on the payload buffer directly
  (with appropriate NoSafepointScopes).

* WriteStreams no longer allocate their initial space on construction,
  but rather on the first write, so no allocation is performed by
  constructing a never-used WriteStream.

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-precomp-mac-release-simarm64-try,vm-kernel-mac-debug-x64-try,vm-kernel-win-debug-x64-try,vm-kernel-win-debug-ia32-try,vm-kernel-precomp-win-release-x64-try,vm-kernel-ubsan-linux-release-x64-try,vm-kernel-tsan-linux-release-x64-try,vm-kernel-precomp-ubsan-linux-release-x64-try,vm-kernel-precomp-tsan-linux-release-x64-try,vm-kernel-precomp-msan-linux-release-x64-try,vm-kernel-precomp-asan-linux-release-x64-try,vm-kernel-msan-linux-release-x64-try,vm-kernel-asan-linux-release-x64-try
Change-Id: Ice63321abaa79157fbe9f230a864c8bba0e6dea9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/166421
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
2020-10-09 10:08:16 +00:00

558 lines
22 KiB
C++
Raw Blame History

// Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#ifndef RUNTIME_VM_KERNEL_BINARY_H_
#define RUNTIME_VM_KERNEL_BINARY_H_
#if !defined(DART_PRECOMPILED_RUNTIME)
#include "platform/unaligned.h"
#include "vm/kernel.h"
#include "vm/object.h"
namespace dart {
namespace kernel {
// Keep in sync with package:kernel/lib/binary/tag.dart,
// package:kernel/binary.md.
static const uint32_t kMagicProgramFile = 0x90ABCDEFu;
// Both version numbers are inclusive.
static const uint32_t kMinSupportedKernelFormatVersion = 46;
static const uint32_t kMaxSupportedKernelFormatVersion = 46;
// Keep in sync with package:kernel/lib/binary/tag.dart
#define KERNEL_TAG_LIST(V) \
V(Nothing, 0) \
V(Something, 1) \
V(Class, 2) \
V(Extension, 115) \
V(FunctionNode, 3) \
V(Field, 4) \
V(Constructor, 5) \
V(Procedure, 6) \
V(RedirectingFactoryConstructor, 108) \
V(InvalidInitializer, 7) \
V(FieldInitializer, 8) \
V(SuperInitializer, 9) \
V(RedirectingInitializer, 10) \
V(LocalInitializer, 11) \
V(AssertInitializer, 12) \
V(CheckLibraryIsLoaded, 13) \
V(LoadLibrary, 14) \
V(ConstStaticInvocation, 18) \
V(InvalidExpression, 19) \
V(VariableGet, 20) \
V(VariableSet, 21) \
V(PropertyGet, 22) \
V(PropertySet, 23) \
V(SuperPropertyGet, 24) \
V(SuperPropertySet, 25) \
V(StaticGet, 26) \
V(StaticSet, 27) \
V(MethodInvocation, 28) \
V(SuperMethodInvocation, 29) \
V(StaticInvocation, 30) \
V(ConstructorInvocation, 31) \
V(ConstConstructorInvocation, 32) \
V(Not, 33) \
V(NullCheck, 117) \
V(LogicalExpression, 34) \
V(ConditionalExpression, 35) \
V(StringConcatenation, 36) \
V(ListConcatenation, 111) \
V(SetConcatenation, 112) \
V(MapConcatenation, 113) \
V(InstanceCreation, 114) \
V(FileUriExpression, 116) \
V(IsExpression, 37) \
V(AsExpression, 38) \
V(StringLiteral, 39) \
V(DoubleLiteral, 40) \
V(TrueLiteral, 41) \
V(FalseLiteral, 42) \
V(NullLiteral, 43) \
V(SymbolLiteral, 44) \
V(TypeLiteral, 45) \
V(ThisExpression, 46) \
V(Rethrow, 47) \
V(Throw, 48) \
V(ListLiteral, 49) \
V(SetLiteral, 109) \
V(MapLiteral, 50) \
V(AwaitExpression, 51) \
V(FunctionExpression, 52) \
V(Let, 53) \
V(BlockExpression, 82) \
V(Instantiation, 54) \
V(PositiveIntLiteral, 55) \
V(NegativeIntLiteral, 56) \
V(BigIntLiteral, 57) \
V(ConstListLiteral, 58) \
V(ConstSetLiteral, 110) \
V(ConstMapLiteral, 59) \
V(ExpressionStatement, 61) \
V(Block, 62) \
V(EmptyStatement, 63) \
V(AssertStatement, 64) \
V(LabeledStatement, 65) \
V(BreakStatement, 66) \
V(WhileStatement, 67) \
V(DoStatement, 68) \
V(ForStatement, 69) \
V(ForInStatement, 70) \
V(SwitchStatement, 71) \
V(ContinueSwitchStatement, 72) \
V(IfStatement, 73) \
V(ReturnStatement, 74) \
V(TryCatch, 75) \
V(TryFinally, 76) \
V(YieldStatement, 77) \
V(VariableDeclaration, 78) \
V(FunctionDeclaration, 79) \
V(AsyncForInStatement, 80) \
V(AssertBlock, 81) \
V(TypedefType, 87) \
V(BottomType, 89) \
V(NeverType, 98) \
V(InvalidType, 90) \
V(DynamicType, 91) \
V(VoidType, 92) \
V(InterfaceType, 93) \
V(FunctionType, 94) \
V(TypeParameterType, 95) \
V(SimpleInterfaceType, 96) \
V(SimpleFunctionType, 97) \
V(ConstantExpression, 106) \
V(SpecializedVariableGet, 128) \
V(SpecializedVariableSet, 136) \
V(SpecializedIntLiteral, 144)
static const intptr_t kSpecializedTagHighBit = 0x80;
static const intptr_t kSpecializedTagMask = 0xf8;
static const intptr_t kSpecializedPayloadMask = 0x7;
enum Tag {
#define DECLARE(Name, value) k##Name = value,
KERNEL_TAG_LIST(DECLARE)
#undef DECLARE
};
// Keep in sync with package:kernel/lib/binary/tag.dart
enum ConstantTag {
kNullConstant = 0,
kBoolConstant = 1,
kIntConstant = 2,
kDoubleConstant = 3,
kStringConstant = 4,
kSymbolConstant = 5,
kMapConstant = 6,
kListConstant = 7,
kSetConstant = 13,
kInstanceConstant = 8,
kPartialInstantiationConstant = 9,
kTearOffConstant = 10,
kTypeLiteralConstant = 11,
// These constants are not expected to be seen by the VM, because all
// constants are fully evaluated.
kUnevaluatedConstant = 12,
};
// Keep in sync with package:kernel/lib/ast.dart
enum class KernelNullability : int8_t {
kUndetermined = 0,
kNullable = 1,
kNonNullable = 2,
kLegacy = 3,
};
// Keep in sync with package:kernel/lib/ast.dart
enum Variance {
kUnrelated = 0,
kCovariant = 1,
kContravariant = 2,
kInvariant = 3,
kLegacyCovariant = 4,
};
// Keep in sync with package:kernel/lib/ast.dart
enum AsExpressionFlags {
kAsExpressionFlagTypeError = 1 << 0,
kAsExpressionFlagCovarianceCheck = 1 << 1,
kAsExpressionFlagForDynamic = 1 << 2,
kAsExpressionFlagForNonNullableByDefault = 1 << 3,
};
// Keep in sync with package:kernel/lib/ast.dart
enum IsExpressionFlags {
kIsExpressionFlagForNonNullableByDefault = 1 << 0,
};
// Keep in sync with package:kernel/lib/ast.dart
enum class NamedTypeFlags : uint8_t {
kIsRequired = 1 << 0,
};
static const int SpecializedIntLiteralBias = 3;
static const int LibraryCountFieldCountFromEnd = 1;
static const int KernelFormatVersionOffset = 4;
static const int SourceTableFieldCountFromFirstLibraryOffsetPre41 = 6;
static const int SourceTableFieldCountFromFirstLibraryOffset41Plus = 7;
static const int HeaderSize = 8; // 'magic', 'formatVersion'.
class Reader : public ValueObject {
public:
Reader(const uint8_t* buffer, intptr_t size)
: thread_(NULL),
raw_buffer_(buffer),
typed_data_(NULL),
size_(size),
offset_(0) {}
explicit Reader(const ExternalTypedData& typed_data)
: thread_(Thread::Current()),
raw_buffer_(NULL),
typed_data_(&typed_data),
size_(typed_data.IsNull() ? 0 : typed_data.Length()),
offset_(0) {}
uint32_t ReadFromIndex(intptr_t end_offset,
intptr_t fields_before,
intptr_t list_size,
intptr_t list_index) {
intptr_t org_offset = offset();
uint32_t result =
ReadFromIndexNoReset(end_offset, fields_before, list_size, list_index);
set_offset(org_offset);
return result;
}
uint32_t ReadUInt32At(intptr_t offset) const {
ASSERT((size_ >= 4) && (offset >= 0) && (offset <= size_ - 4));
uint32_t value;
if (raw_buffer_ != NULL) {
value = LoadUnaligned(
reinterpret_cast<const uint32_t*>(raw_buffer_ + offset));
} else {
value = typed_data_->GetUint32(offset);
}
return Utils::BigEndianToHost32(value);
}
uint32_t ReadFromIndexNoReset(intptr_t end_offset,
intptr_t fields_before,
intptr_t list_size,
intptr_t list_index) {
set_offset(end_offset - (fields_before + list_size - list_index) * 4);
return ReadUInt32();
}
uint32_t ReadUInt32() {
uint32_t value = ReadUInt32At(offset_);
offset_ += 4;
return value;
}
double ReadDouble() {
ASSERT((size_ >= 8) && (offset_ >= 0) && (offset_ <= size_ - 8));
double value = LoadUnaligned(
reinterpret_cast<const double*>(&this->buffer()[offset_]));
offset_ += 8;
return value;
}
uint32_t ReadUInt() {
ASSERT((size_ >= 1) && (offset_ >= 0) && (offset_ <= size_ - 1));
const uint8_t* buffer = this->buffer();
uint8_t byte0 = buffer[offset_];
if ((byte0 & 0x80) == 0) {
// 0...
offset_++;
return byte0;
} else if ((byte0 & 0xc0) == 0x80) {
// 10...
ASSERT((size_ >= 2) && (offset_ >= 0) && (offset_ <= size_ - 2));
uint32_t value = ((byte0 & ~0x80) << 8) | (buffer[offset_ + 1]);
offset_ += 2;
return value;
} else {
// 11...
ASSERT((size_ >= 4) && (offset_ >= 0) && (offset_ <= size_ - 4));
uint32_t value = ((byte0 & ~0xc0) << 24) | (buffer[offset_ + 1] << 16) |
(buffer[offset_ + 2] << 8) | (buffer[offset_ + 3] << 0);
offset_ += 4;
return value;
}
}
intptr_t ReadSLEB128() {
ReadStream stream(this->buffer(), size_, offset_);
const intptr_t result = stream.ReadSLEB128();
offset_ = stream.Position();
return result;
}
int64_t ReadSLEB128AsInt64() {
ReadStream stream(this->buffer(), size_, offset_);
const int64_t result = stream.ReadSLEB128<int64_t>();
offset_ = stream.Position();
return result;
}
/**
* Read and return a TokenPosition from this reader.
*/
TokenPosition ReadPosition() {
// Position is saved as unsigned,
// but actually ranges from -1 and up (thus the -1)
intptr_t value = ReadUInt() - 1;
TokenPosition result = TokenPosition(value);
max_position_ = Utils::Maximum(max_position_, result);
if (min_position_.IsNoSource()) {
min_position_ = result;
} else if (result.IsReal()) {
min_position_ = Utils::Minimum(min_position_, result);
}
return result;
}
intptr_t ReadListLength() { return ReadUInt(); }
uint8_t ReadByte() { return buffer()[offset_++]; }
uint8_t PeekByte() { return buffer()[offset_]; }
void ReadBytes(uint8_t* buffer, uint8_t size) {
for (int i = 0; i < size; i++) {
buffer[i] = ReadByte();
}
}
bool ReadBool() { return (ReadByte() & 1) == 1; }
uint8_t ReadFlags() { return ReadByte(); }
static const char* TagName(Tag tag);
Tag ReadTag(uint8_t* payload = NULL) {
uint8_t byte = ReadByte();
bool has_payload = (byte & kSpecializedTagHighBit) != 0;
if (has_payload) {
if (payload != NULL) {
*payload = byte & kSpecializedPayloadMask;
}
return static_cast<Tag>(byte & kSpecializedTagMask);
} else {
return static_cast<Tag>(byte);
}
}
Tag PeekTag(uint8_t* payload = NULL) {
uint8_t byte = PeekByte();
bool has_payload = (byte & kSpecializedTagHighBit) != 0;
if (has_payload) {
if (payload != NULL) {
*payload = byte & kSpecializedPayloadMask;
}
return static_cast<Tag>(byte & kSpecializedTagMask);
} else {
return static_cast<Tag>(byte);
}
}
static Nullability ConvertNullability(KernelNullability kernel_nullability) {
switch (kernel_nullability) {
case KernelNullability::kNullable:
return Nullability::kNullable;
case KernelNullability::kLegacy:
return Nullability::kLegacy;
case KernelNullability::kNonNullable:
case KernelNullability::kUndetermined:
return Nullability::kNonNullable;
}
UNREACHABLE();
}
Nullability ReadNullability() {
const uint8_t byte = ReadByte();
return ConvertNullability(static_cast<KernelNullability>(byte));
}
Variance ReadVariance() {
uint8_t byte = ReadByte();
return static_cast<Variance>(byte);
}
void EnsureEnd() {
if (offset_ != size_) {
FATAL2(
"Reading Kernel file: Expected to be at EOF "
"(offset: %" Pd ", size: %" Pd ")",
offset_, size_);
}
}
// The largest position read yet (since last reset).
// This is automatically updated when calling ReadPosition,
// but can be overwritten (e.g. via the PositionScope class).
TokenPosition max_position() { return max_position_; }
// The smallest position read yet (since last reset).
// This is automatically updated when calling ReadPosition,
// but can be overwritten (e.g. via the PositionScope class).
TokenPosition min_position() { return min_position_; }
// A canonical name reference of -1 indicates none (for optional names), not
// the root name as in the canonical name table.
NameIndex ReadCanonicalNameReference() { return NameIndex(ReadUInt() - 1); }
intptr_t offset() const { return offset_; }
void set_offset(intptr_t offset) { offset_ = offset; }
intptr_t size() const { return size_; }
void set_size(intptr_t size) { size_ = size; }
const ExternalTypedData* typed_data() const { return typed_data_; }
void set_typed_data(const ExternalTypedData* typed_data) {
typed_data_ = typed_data;
}
const uint8_t* raw_buffer() const { return raw_buffer_; }
void set_raw_buffer(const uint8_t* raw_buffer) { raw_buffer_ = raw_buffer; }
ExternalTypedDataPtr ExternalDataFromTo(intptr_t start, intptr_t end) {
return ExternalTypedData::New(kExternalTypedDataUint8ArrayCid,
const_cast<uint8_t*>(buffer() + start),
end - start, Heap::kOld);
}
const uint8_t* BufferAt(intptr_t offset) {
ASSERT((offset >= 0) && (offset < size_));
return &buffer()[offset];
}
TypedDataPtr ReadLineStartsData(intptr_t line_start_count);
private:
const uint8_t* buffer() const {
if (raw_buffer_ != NULL) {
return raw_buffer_;
}
NoSafepointScope no_safepoint(thread_);
return reinterpret_cast<uint8_t*>(typed_data_->DataAddr(0));
}
Thread* thread_;
const uint8_t* raw_buffer_;
const ExternalTypedData* typed_data_;
intptr_t size_;
intptr_t offset_;
TokenPosition max_position_;
TokenPosition min_position_;
intptr_t current_script_id_;
friend class PositionScope;
friend class Program;
};
// A helper class that saves the current reader position, goes to another reader
// position, and upon destruction, resets to the original reader position.
class AlternativeReadingScope {
public:
AlternativeReadingScope(Reader* reader, intptr_t new_position)
: reader_(reader), saved_offset_(reader_->offset()) {
reader_->set_offset(new_position);
}
explicit AlternativeReadingScope(Reader* reader)
: reader_(reader), saved_offset_(reader_->offset()) {}
~AlternativeReadingScope() { reader_->set_offset(saved_offset_); }
intptr_t saved_offset() { return saved_offset_; }
private:
Reader* const reader_;
const intptr_t saved_offset_;
DISALLOW_COPY_AND_ASSIGN(AlternativeReadingScope);
};
// Similar to AlternativeReadingScope, but also switches reading to another
// typed data array.
class AlternativeReadingScopeWithNewData {
public:
AlternativeReadingScopeWithNewData(Reader* reader,
const ExternalTypedData* new_typed_data,
intptr_t new_position)
: reader_(reader),
saved_size_(reader_->size()),
saved_raw_buffer_(reader_->raw_buffer()),
saved_typed_data_(reader_->typed_data()),
saved_offset_(reader_->offset()) {
reader_->set_raw_buffer(nullptr);
reader_->set_typed_data(new_typed_data);
reader_->set_size(new_typed_data->Length());
reader_->set_offset(new_position);
}
~AlternativeReadingScopeWithNewData() {
reader_->set_raw_buffer(saved_raw_buffer_);
reader_->set_typed_data(saved_typed_data_);
reader_->set_size(saved_size_);
reader_->set_offset(saved_offset_);
}
intptr_t saved_offset() { return saved_offset_; }
private:
Reader* reader_;
intptr_t saved_size_;
const uint8_t* saved_raw_buffer_;
const ExternalTypedData* saved_typed_data_;
intptr_t saved_offset_;
DISALLOW_COPY_AND_ASSIGN(AlternativeReadingScopeWithNewData);
};
// A helper class that resets the readers min and max positions both upon
// initialization and upon destruction, i.e. when created the min an max
// positions will be reset to "noSource", when destructing the min and max will
// be reset to have they value they would have had, if they hadn't been reset in
// the first place.
class PositionScope {
public:
explicit PositionScope(Reader* reader)
: reader_(reader),
min_(reader->min_position_),
max_(reader->max_position_) {
reader->min_position_ = reader->max_position_ = TokenPosition::kNoSource;
}
~PositionScope() {
if (reader_->min_position_.IsNoSource()) {
reader_->min_position_ = min_;
} else if (min_.IsReal()) {
reader_->min_position_ = Utils::Minimum(reader_->min_position_, min_);
}
reader_->max_position_ = Utils::Maximum(reader_->max_position_, max_);
}
private:
Reader* reader_;
TokenPosition min_;
TokenPosition max_;
DISALLOW_COPY_AND_ASSIGN(PositionScope);
};
} // namespace kernel
} // namespace dart
#endif // !defined(DART_PRECOMPILED_RUNTIME)
#endif // RUNTIME_VM_KERNEL_BINARY_H_
Reference in New Issue View Git Blame Copy Permalink