ladybird/Userland/Libraries/LibWasm/Parser/Parser.cpp
2023-01-25 17:10:05 +03:30

1427 lines
54 KiB
C++

/*
* Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Debug.h>
#include <AK/LEB128.h>
#include <AK/ScopeGuard.h>
#include <AK/ScopeLogger.h>
#include <LibCore/MemoryStream.h>
#include <LibWasm/Types.h>
namespace Wasm {
ParseError with_eof_check(Core::Stream::Stream const& stream, ParseError error_if_not_eof)
{
if (stream.is_eof())
return ParseError::UnexpectedEof;
return error_if_not_eof;
}
template<typename T>
static auto parse_vector(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger;
if constexpr (requires { T::parse(stream); }) {
using ResultT = typename decltype(T::parse(stream))::ValueType;
size_t count;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, count))
return ParseResult<Vector<ResultT>> { with_eof_check(stream, ParseError::ExpectedSize) };
Vector<ResultT> entries;
for (size_t i = 0; i < count; ++i) {
auto result = T::parse(stream);
if (result.is_error())
return ParseResult<Vector<ResultT>> { result.error() };
entries.append(result.release_value());
}
return ParseResult<Vector<ResultT>> { move(entries) };
} else {
size_t count;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, count))
return ParseResult<Vector<T>> { with_eof_check(stream, ParseError::ExpectedSize) };
Vector<T> entries;
for (size_t i = 0; i < count; ++i) {
if constexpr (IsSame<T, size_t>) {
size_t value;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, value))
return ParseResult<Vector<T>> { with_eof_check(stream, ParseError::ExpectedSize) };
entries.append(value);
} else if constexpr (IsSame<T, ssize_t>) {
ssize_t value;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_signed(wrapped_stream, value))
return ParseResult<Vector<T>> { with_eof_check(stream, ParseError::ExpectedSize) };
entries.append(value);
} else if constexpr (IsSame<T, u8>) {
if (count > Constants::max_allowed_vector_size)
return ParseResult<Vector<T>> { ParseError::HugeAllocationRequested };
entries.resize(count);
if (stream.read_entire_buffer({ entries.data(), entries.size() }).is_error())
return ParseResult<Vector<T>> { with_eof_check(stream, ParseError::InvalidInput) };
break; // Note: We read this all in one go!
}
}
return ParseResult<Vector<T>> { move(entries) };
}
}
static ParseResult<DeprecatedString> parse_name(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger;
auto data = parse_vector<u8>(stream);
if (data.is_error())
return data.error();
return DeprecatedString::copy(data.value());
}
template<typename T>
struct ParseUntilAnyOfResult {
u8 terminator { 0 };
Vector<T> values;
};
template<typename T, u8... terminators, typename... Args>
static ParseResult<ParseUntilAnyOfResult<T>> parse_until_any_of(Core::Stream::Stream& stream, Args&... args)
requires(requires(Core::Stream::Stream& stream, Args... args) { T::parse(stream, args...); })
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger;
ReconsumableStream new_stream { stream };
ParseUntilAnyOfResult<T> result;
for (;;) {
auto byte_or_error = new_stream.read_value<u8>();
if (byte_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedValueOrTerminator);
auto byte = byte_or_error.release_value();
constexpr auto equals = [](auto&& a, auto&& b) { return a == b; };
if ((... || equals(byte, terminators))) {
result.terminator = byte;
return result;
}
new_stream.unread({ &byte, 1 });
auto parse_result = T::parse(new_stream, args...);
if (parse_result.is_error())
return parse_result.error();
result.values.extend(parse_result.release_value());
}
}
ParseResult<ValueType> ValueType::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("ValueType"sv);
auto tag_or_error = stream.read_value<u8>();
if (tag_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto tag = tag_or_error.release_value();
switch (tag) {
case Constants::i32_tag:
return ValueType(I32);
case Constants::i64_tag:
return ValueType(I64);
case Constants::f32_tag:
return ValueType(F32);
case Constants::f64_tag:
return ValueType(F64);
case Constants::function_reference_tag:
return ValueType(FunctionReference);
case Constants::extern_reference_tag:
return ValueType(ExternReference);
default:
return with_eof_check(stream, ParseError::InvalidTag);
}
}
ParseResult<ResultType> ResultType::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("ResultType"sv);
auto types = parse_vector<ValueType>(stream);
if (types.is_error())
return types.error();
return ResultType { types.release_value() };
}
ParseResult<FunctionType> FunctionType::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("FunctionType"sv);
auto tag_or_error = stream.read_value<u8>();
if (tag_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto tag = tag_or_error.release_value();
if (tag != Constants::function_signature_tag) {
dbgln("Expected 0x60, but found {:#x}", tag);
return with_eof_check(stream, ParseError::InvalidTag);
}
auto parameters_result = parse_vector<ValueType>(stream);
if (parameters_result.is_error())
return parameters_result.error();
auto results_result = parse_vector<ValueType>(stream);
if (results_result.is_error())
return results_result.error();
return FunctionType { parameters_result.release_value(), results_result.release_value() };
}
ParseResult<Limits> Limits::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Limits"sv);
auto flag_or_error = stream.read_value<u8>();
if (flag_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto flag = flag_or_error.release_value();
if (flag > 1)
return with_eof_check(stream, ParseError::InvalidTag);
size_t min;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, min))
return with_eof_check(stream, ParseError::ExpectedSize);
Optional<u32> max;
if (flag) {
size_t value;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, value))
return with_eof_check(stream, ParseError::ExpectedSize);
max = value;
}
return Limits { static_cast<u32>(min), move(max) };
}
ParseResult<MemoryType> MemoryType::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("MemoryType"sv);
auto limits_result = Limits::parse(stream);
if (limits_result.is_error())
return limits_result.error();
return MemoryType { limits_result.release_value() };
}
ParseResult<TableType> TableType::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("TableType"sv);
auto type_result = ValueType::parse(stream);
if (type_result.is_error())
return type_result.error();
if (!type_result.value().is_reference())
return with_eof_check(stream, ParseError::InvalidType);
auto limits_result = Limits::parse(stream);
if (limits_result.is_error())
return limits_result.error();
return TableType { type_result.release_value(), limits_result.release_value() };
}
ParseResult<GlobalType> GlobalType::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("GlobalType"sv);
auto type_result = ValueType::parse(stream);
if (type_result.is_error())
return type_result.error();
auto mutable_or_error = stream.read_value<u8>();
if (mutable_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto mutable_ = mutable_or_error.release_value();
if (mutable_ > 1)
return with_eof_check(stream, ParseError::InvalidTag);
return GlobalType { type_result.release_value(), mutable_ == 0x01 };
}
ParseResult<BlockType> BlockType::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("BlockType"sv);
auto kind_or_error = stream.read_value<u8>();
if (kind_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto kind = kind_or_error.release_value();
if (kind == Constants::empty_block_tag)
return BlockType {};
{
auto value_stream = Core::Stream::FixedMemoryStream::construct(ReadonlyBytes { &kind, 1 }).release_value_but_fixme_should_propagate_errors();
if (auto value_type = ValueType::parse(*value_stream); !value_type.is_error())
return BlockType { value_type.release_value() };
}
ReconsumableStream new_stream { stream };
new_stream.unread({ &kind, 1 });
ssize_t index_value;
Core::Stream::WrapInAKInputStream wrapped_new_stream { new_stream };
if (!LEB128::read_signed(wrapped_new_stream, index_value))
return with_eof_check(stream, ParseError::ExpectedIndex);
if (index_value < 0) {
dbgln("Invalid type index {}", index_value);
return with_eof_check(stream, ParseError::InvalidIndex);
}
return BlockType { TypeIndex(index_value) };
}
ParseResult<Vector<Instruction>> Instruction::parse(Core::Stream::Stream& stream, InstructionPointer& ip)
{
struct NestedInstructionState {
Vector<Instruction> prior_instructions;
OpCode opcode;
BlockType block_type;
InstructionPointer end_ip;
Optional<InstructionPointer> else_ip;
};
Vector<NestedInstructionState, 4> nested_instructions;
Vector<Instruction> resulting_instructions;
do {
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Instruction"sv);
auto byte_or_error = stream.read_value<u8>();
if (byte_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto byte = byte_or_error.release_value();
if (!nested_instructions.is_empty()) {
auto& nested_structure = nested_instructions.last();
if (byte == 0x0b) {
// block/loop/if end
nested_structure.end_ip = ip + (nested_structure.else_ip.has_value() ? 1 : 0);
++ip;
// Transform op(..., instr*) -> op(...) instr* op(end(ip))
auto instructions = move(nested_structure.prior_instructions);
instructions.ensure_capacity(instructions.size() + 2 + resulting_instructions.size());
instructions.append(Instruction { nested_structure.opcode, StructuredInstructionArgs { nested_structure.block_type, nested_structure.end_ip, nested_structure.else_ip } });
instructions.extend(move(resulting_instructions));
instructions.append(Instruction { Instructions::structured_end });
resulting_instructions = move(instructions);
nested_instructions.take_last();
continue;
}
if (byte == 0x05) {
// if...else
// Transform op(..., instr*, instr*) -> op(...) instr* op(else(ip) instr* op(end(ip))
resulting_instructions.append(Instruction { Instructions::structured_else });
++ip;
nested_structure.else_ip = ip.value();
continue;
}
}
OpCode opcode { byte };
++ip;
switch (opcode.value()) {
case Instructions::block.value():
case Instructions::loop.value():
case Instructions::if_.value(): {
auto block_type = BlockType::parse(stream);
if (block_type.is_error())
return block_type.error();
nested_instructions.append({ move(resulting_instructions), opcode, block_type.release_value(), {}, {} });
resulting_instructions = {};
break;
}
case Instructions::br.value():
case Instructions::br_if.value(): {
// branches with a single label immediate
auto index = GenericIndexParser<LabelIndex>::parse(stream);
if (index.is_error())
return index.error();
resulting_instructions.append(Instruction { opcode, index.release_value() });
break;
}
case Instructions::br_table.value(): {
// br_table label* label
auto labels = parse_vector<GenericIndexParser<LabelIndex>>(stream);
if (labels.is_error())
return labels.error();
auto default_label = GenericIndexParser<LabelIndex>::parse(stream);
if (default_label.is_error())
return default_label.error();
resulting_instructions.append(Instruction { opcode, TableBranchArgs { labels.release_value(), default_label.release_value() } });
break;
}
case Instructions::call.value(): {
// call function
auto function_index = GenericIndexParser<FunctionIndex>::parse(stream);
if (function_index.is_error())
return function_index.error();
resulting_instructions.append(Instruction { opcode, function_index.release_value() });
break;
}
case Instructions::call_indirect.value(): {
// call_indirect type table
auto type_index = GenericIndexParser<TypeIndex>::parse(stream);
if (type_index.is_error())
return type_index.error();
auto table_index = GenericIndexParser<TableIndex>::parse(stream);
if (table_index.is_error())
return table_index.error();
resulting_instructions.append(Instruction { opcode, IndirectCallArgs { type_index.release_value(), table_index.release_value() } });
break;
}
case Instructions::i32_load.value():
case Instructions::i64_load.value():
case Instructions::f32_load.value():
case Instructions::f64_load.value():
case Instructions::i32_load8_s.value():
case Instructions::i32_load8_u.value():
case Instructions::i32_load16_s.value():
case Instructions::i32_load16_u.value():
case Instructions::i64_load8_s.value():
case Instructions::i64_load8_u.value():
case Instructions::i64_load16_s.value():
case Instructions::i64_load16_u.value():
case Instructions::i64_load32_s.value():
case Instructions::i64_load32_u.value():
case Instructions::i32_store.value():
case Instructions::i64_store.value():
case Instructions::f32_store.value():
case Instructions::f64_store.value():
case Instructions::i32_store8.value():
case Instructions::i32_store16.value():
case Instructions::i64_store8.value():
case Instructions::i64_store16.value():
case Instructions::i64_store32.value(): {
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
// op (align offset)
size_t align;
if (!LEB128::read_unsigned(wrapped_stream, align))
return with_eof_check(stream, ParseError::InvalidInput);
size_t offset;
if (!LEB128::read_unsigned(wrapped_stream, offset))
return with_eof_check(stream, ParseError::InvalidInput);
resulting_instructions.append(Instruction { opcode, MemoryArgument { static_cast<u32>(align), static_cast<u32>(offset) } });
break;
}
case Instructions::local_get.value():
case Instructions::local_set.value():
case Instructions::local_tee.value(): {
auto index = GenericIndexParser<LocalIndex>::parse(stream);
if (index.is_error())
return index.error();
resulting_instructions.append(Instruction { opcode, index.release_value() });
break;
}
case Instructions::global_get.value():
case Instructions::global_set.value(): {
auto index = GenericIndexParser<GlobalIndex>::parse(stream);
if (index.is_error())
return index.error();
resulting_instructions.append(Instruction { opcode, index.release_value() });
break;
}
case Instructions::memory_size.value():
case Instructions::memory_grow.value(): {
// op 0x0
// The zero is currently unused.
auto unused_or_error = stream.read_value<u8>();
if (unused_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto unused = unused_or_error.release_value();
if (unused != 0x00) {
dbgln("Invalid tag in memory_grow {}", unused);
return with_eof_check(stream, ParseError::InvalidTag);
}
resulting_instructions.append(Instruction { opcode });
break;
}
case Instructions::i32_const.value(): {
i32 value;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_signed(wrapped_stream, value))
return with_eof_check(stream, ParseError::ExpectedSignedImmediate);
resulting_instructions.append(Instruction { opcode, value });
break;
}
case Instructions::i64_const.value(): {
// op literal
i64 value;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_signed(wrapped_stream, value))
return with_eof_check(stream, ParseError::ExpectedSignedImmediate);
resulting_instructions.append(Instruction { opcode, value });
break;
}
case Instructions::f32_const.value(): {
// op literal
LittleEndian<u32> value;
if (stream.read_entire_buffer(value.bytes()).is_error())
return with_eof_check(stream, ParseError::ExpectedFloatingImmediate);
auto floating = bit_cast<float>(static_cast<u32>(value));
resulting_instructions.append(Instruction { opcode, floating });
break;
}
case Instructions::f64_const.value(): {
// op literal
LittleEndian<u64> value;
if (stream.read_entire_buffer(value.bytes()).is_error())
return with_eof_check(stream, ParseError::ExpectedFloatingImmediate);
auto floating = bit_cast<double>(static_cast<u64>(value));
resulting_instructions.append(Instruction { opcode, floating });
break;
}
case Instructions::table_get.value():
case Instructions::table_set.value(): {
auto index = GenericIndexParser<TableIndex>::parse(stream);
if (index.is_error())
return index.error();
resulting_instructions.append(Instruction { opcode, index.release_value() });
break;
}
case Instructions::select_typed.value(): {
auto types = parse_vector<ValueType>(stream);
if (types.is_error())
return types.error();
resulting_instructions.append(Instruction { opcode, types.release_value() });
break;
}
case Instructions::ref_null.value(): {
auto type = ValueType::parse(stream);
if (type.is_error())
return type.error();
if (!type.value().is_reference())
return ParseError::InvalidType;
resulting_instructions.append(Instruction { opcode, type.release_value() });
break;
}
case Instructions::ref_func.value(): {
auto index = GenericIndexParser<FunctionIndex>::parse(stream);
if (index.is_error())
return index.error();
resulting_instructions.append(Instruction { opcode, index.release_value() });
break;
}
case Instructions::ref_is_null.value():
case Instructions::unreachable.value():
case Instructions::nop.value():
case Instructions::return_.value():
case Instructions::drop.value():
case Instructions::select.value():
case Instructions::i32_eqz.value():
case Instructions::i32_eq.value():
case Instructions::i32_ne.value():
case Instructions::i32_lts.value():
case Instructions::i32_ltu.value():
case Instructions::i32_gts.value():
case Instructions::i32_gtu.value():
case Instructions::i32_les.value():
case Instructions::i32_leu.value():
case Instructions::i32_ges.value():
case Instructions::i32_geu.value():
case Instructions::i64_eqz.value():
case Instructions::i64_eq.value():
case Instructions::i64_ne.value():
case Instructions::i64_lts.value():
case Instructions::i64_ltu.value():
case Instructions::i64_gts.value():
case Instructions::i64_gtu.value():
case Instructions::i64_les.value():
case Instructions::i64_leu.value():
case Instructions::i64_ges.value():
case Instructions::i64_geu.value():
case Instructions::f32_eq.value():
case Instructions::f32_ne.value():
case Instructions::f32_lt.value():
case Instructions::f32_gt.value():
case Instructions::f32_le.value():
case Instructions::f32_ge.value():
case Instructions::f64_eq.value():
case Instructions::f64_ne.value():
case Instructions::f64_lt.value():
case Instructions::f64_gt.value():
case Instructions::f64_le.value():
case Instructions::f64_ge.value():
case Instructions::i32_clz.value():
case Instructions::i32_ctz.value():
case Instructions::i32_popcnt.value():
case Instructions::i32_add.value():
case Instructions::i32_sub.value():
case Instructions::i32_mul.value():
case Instructions::i32_divs.value():
case Instructions::i32_divu.value():
case Instructions::i32_rems.value():
case Instructions::i32_remu.value():
case Instructions::i32_and.value():
case Instructions::i32_or.value():
case Instructions::i32_xor.value():
case Instructions::i32_shl.value():
case Instructions::i32_shrs.value():
case Instructions::i32_shru.value():
case Instructions::i32_rotl.value():
case Instructions::i32_rotr.value():
case Instructions::i64_clz.value():
case Instructions::i64_ctz.value():
case Instructions::i64_popcnt.value():
case Instructions::i64_add.value():
case Instructions::i64_sub.value():
case Instructions::i64_mul.value():
case Instructions::i64_divs.value():
case Instructions::i64_divu.value():
case Instructions::i64_rems.value():
case Instructions::i64_remu.value():
case Instructions::i64_and.value():
case Instructions::i64_or.value():
case Instructions::i64_xor.value():
case Instructions::i64_shl.value():
case Instructions::i64_shrs.value():
case Instructions::i64_shru.value():
case Instructions::i64_rotl.value():
case Instructions::i64_rotr.value():
case Instructions::f32_abs.value():
case Instructions::f32_neg.value():
case Instructions::f32_ceil.value():
case Instructions::f32_floor.value():
case Instructions::f32_trunc.value():
case Instructions::f32_nearest.value():
case Instructions::f32_sqrt.value():
case Instructions::f32_add.value():
case Instructions::f32_sub.value():
case Instructions::f32_mul.value():
case Instructions::f32_div.value():
case Instructions::f32_min.value():
case Instructions::f32_max.value():
case Instructions::f32_copysign.value():
case Instructions::f64_abs.value():
case Instructions::f64_neg.value():
case Instructions::f64_ceil.value():
case Instructions::f64_floor.value():
case Instructions::f64_trunc.value():
case Instructions::f64_nearest.value():
case Instructions::f64_sqrt.value():
case Instructions::f64_add.value():
case Instructions::f64_sub.value():
case Instructions::f64_mul.value():
case Instructions::f64_div.value():
case Instructions::f64_min.value():
case Instructions::f64_max.value():
case Instructions::f64_copysign.value():
case Instructions::i32_wrap_i64.value():
case Instructions::i32_trunc_sf32.value():
case Instructions::i32_trunc_uf32.value():
case Instructions::i32_trunc_sf64.value():
case Instructions::i32_trunc_uf64.value():
case Instructions::i64_extend_si32.value():
case Instructions::i64_extend_ui32.value():
case Instructions::i64_trunc_sf32.value():
case Instructions::i64_trunc_uf32.value():
case Instructions::i64_trunc_sf64.value():
case Instructions::i64_trunc_uf64.value():
case Instructions::f32_convert_si32.value():
case Instructions::f32_convert_ui32.value():
case Instructions::f32_convert_si64.value():
case Instructions::f32_convert_ui64.value():
case Instructions::f32_demote_f64.value():
case Instructions::f64_convert_si32.value():
case Instructions::f64_convert_ui32.value():
case Instructions::f64_convert_si64.value():
case Instructions::f64_convert_ui64.value():
case Instructions::f64_promote_f32.value():
case Instructions::i32_reinterpret_f32.value():
case Instructions::i64_reinterpret_f64.value():
case Instructions::f32_reinterpret_i32.value():
case Instructions::f64_reinterpret_i64.value():
case Instructions::i32_extend8_s.value():
case Instructions::i32_extend16_s.value():
case Instructions::i64_extend8_s.value():
case Instructions::i64_extend16_s.value():
case Instructions::i64_extend32_s.value():
resulting_instructions.append(Instruction { opcode });
break;
case 0xfc: {
// These are multibyte instructions.
u32 selector;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, selector))
return with_eof_check(stream, ParseError::InvalidInput);
switch (selector) {
case Instructions::i32_trunc_sat_f32_s_second:
case Instructions::i32_trunc_sat_f32_u_second:
case Instructions::i32_trunc_sat_f64_s_second:
case Instructions::i32_trunc_sat_f64_u_second:
case Instructions::i64_trunc_sat_f32_s_second:
case Instructions::i64_trunc_sat_f32_u_second:
case Instructions::i64_trunc_sat_f64_s_second:
case Instructions::i64_trunc_sat_f64_u_second:
resulting_instructions.append(Instruction { OpCode { 0xfc00 | selector } });
break;
case Instructions::memory_init_second: {
auto index = GenericIndexParser<DataIndex>::parse(stream);
if (index.is_error())
return index.error();
auto unused_or_error = stream.read_value<u8>();
if (unused_or_error.is_error())
return with_eof_check(stream, ParseError::InvalidInput);
auto unused = unused_or_error.release_value();
if (unused != 0x00)
return ParseError::InvalidImmediate;
resulting_instructions.append(Instruction { OpCode { 0xfc00 | selector }, index.release_value() });
break;
}
case Instructions::data_drop_second: {
auto index = GenericIndexParser<DataIndex>::parse(stream);
if (index.is_error())
return index.error();
resulting_instructions.append(Instruction { OpCode { 0xfc00 | selector }, index.release_value() });
break;
}
case Instructions::memory_copy_second: {
for (size_t i = 0; i < 2; ++i) {
auto unused_or_error = stream.read_value<u8>();
if (unused_or_error.is_error())
return with_eof_check(stream, ParseError::InvalidInput);
auto unused = unused_or_error.release_value();
if (unused != 0x00)
return ParseError::InvalidImmediate;
}
resulting_instructions.append(Instruction { OpCode { 0xfc00 | selector } });
break;
}
case Instructions::memory_fill_second: {
auto unused_or_error = stream.read_value<u8>();
if (unused_or_error.is_error())
return with_eof_check(stream, ParseError::InvalidInput);
auto unused = unused_or_error.release_value();
if (unused != 0x00)
return ParseError::InvalidImmediate;
resulting_instructions.append(Instruction { OpCode { 0xfc00 | selector } });
break;
}
case Instructions::table_init_second: {
auto element_index = GenericIndexParser<ElementIndex>::parse(stream);
if (element_index.is_error())
return element_index.error();
auto table_index = GenericIndexParser<TableIndex>::parse(stream);
if (table_index.is_error())
return table_index.error();
resulting_instructions.append(Instruction { OpCode { 0xfc00 | selector }, TableElementArgs { element_index.release_value(), table_index.release_value() } });
break;
}
case Instructions::elem_drop_second: {
auto element_index = GenericIndexParser<ElementIndex>::parse(stream);
if (element_index.is_error())
return element_index.error();
resulting_instructions.append(Instruction { OpCode { 0xfc00 | selector }, element_index.release_value() });
break;
}
case Instructions::table_copy_second: {
auto lhs = GenericIndexParser<TableIndex>::parse(stream);
if (lhs.is_error())
return lhs.error();
auto rhs = GenericIndexParser<TableIndex>::parse(stream);
if (rhs.is_error())
return rhs.error();
resulting_instructions.append(Instruction { OpCode { 0xfc00 | selector }, TableTableArgs { lhs.release_value(), rhs.release_value() } });
break;
}
case Instructions::table_grow_second:
case Instructions::table_size_second:
case Instructions::table_fill_second: {
auto index = GenericIndexParser<TableIndex>::parse(stream);
if (index.is_error())
return index.error();
resulting_instructions.append(Instruction { OpCode { 0xfc00 | selector }, index.release_value() });
break;
}
default:
return ParseError::UnknownInstruction;
}
}
}
} while (!nested_instructions.is_empty());
return resulting_instructions;
}
ParseResult<CustomSection> CustomSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("CustomSection"sv);
auto name = parse_name(stream);
if (name.is_error())
return name.error();
ByteBuffer data_buffer;
if (data_buffer.try_resize(64).is_error())
return ParseError::OutOfMemory;
while (!stream.is_eof()) {
char buf[16];
auto span_or_error = stream.read({ buf, 16 });
if (span_or_error.is_error())
break;
auto size = span_or_error.release_value().size();
if (size == 0)
break;
if (data_buffer.try_append(buf, size).is_error())
return with_eof_check(stream, ParseError::HugeAllocationRequested);
}
return CustomSection(name.release_value(), move(data_buffer));
}
ParseResult<TypeSection> TypeSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("TypeSection"sv);
auto types = parse_vector<FunctionType>(stream);
if (types.is_error())
return types.error();
return TypeSection { types.release_value() };
}
ParseResult<ImportSection::Import> ImportSection::Import::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Import"sv);
auto module = parse_name(stream);
if (module.is_error())
return module.error();
auto name = parse_name(stream);
if (name.is_error())
return name.error();
auto tag_or_error = stream.read_value<u8>();
if (tag_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto tag = tag_or_error.release_value();
switch (tag) {
case Constants::extern_function_tag: {
auto index = GenericIndexParser<TypeIndex>::parse(stream);
if (index.is_error())
return index.error();
return Import { module.release_value(), name.release_value(), index.release_value() };
}
case Constants::extern_table_tag:
return parse_with_type<TableType>(stream, module, name);
case Constants::extern_memory_tag:
return parse_with_type<MemoryType>(stream, module, name);
case Constants::extern_global_tag:
return parse_with_type<GlobalType>(stream, module, name);
default:
return with_eof_check(stream, ParseError::InvalidTag);
}
}
ParseResult<ImportSection> ImportSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("ImportSection"sv);
auto imports = parse_vector<Import>(stream);
if (imports.is_error())
return imports.error();
return ImportSection { imports.release_value() };
}
ParseResult<FunctionSection> FunctionSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("FunctionSection"sv);
auto indices = parse_vector<size_t>(stream);
if (indices.is_error())
return indices.error();
Vector<TypeIndex> typed_indices;
typed_indices.ensure_capacity(indices.value().size());
for (auto entry : indices.value())
typed_indices.append(entry);
return FunctionSection { move(typed_indices) };
}
ParseResult<TableSection::Table> TableSection::Table::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Table"sv);
auto type = TableType::parse(stream);
if (type.is_error())
return type.error();
return Table { type.release_value() };
}
ParseResult<TableSection> TableSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("TableSection"sv);
auto tables = parse_vector<Table>(stream);
if (tables.is_error())
return tables.error();
return TableSection { tables.release_value() };
}
ParseResult<MemorySection::Memory> MemorySection::Memory::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Memory"sv);
auto type = MemoryType::parse(stream);
if (type.is_error())
return type.error();
return Memory { type.release_value() };
}
ParseResult<MemorySection> MemorySection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("MemorySection"sv);
auto memories = parse_vector<Memory>(stream);
if (memories.is_error())
return memories.error();
return MemorySection { memories.release_value() };
}
ParseResult<Expression> Expression::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Expression"sv);
InstructionPointer ip { 0 };
auto instructions = parse_until_any_of<Instruction, 0x0b>(stream, ip);
if (instructions.is_error())
return instructions.error();
return Expression { move(instructions.value().values) };
}
ParseResult<GlobalSection::Global> GlobalSection::Global::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Global"sv);
auto type = GlobalType::parse(stream);
if (type.is_error())
return type.error();
auto exprs = Expression::parse(stream);
if (exprs.is_error())
return exprs.error();
return Global { type.release_value(), exprs.release_value() };
}
ParseResult<GlobalSection> GlobalSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("GlobalSection"sv);
auto result = parse_vector<Global>(stream);
if (result.is_error())
return result.error();
return GlobalSection { result.release_value() };
}
ParseResult<ExportSection::Export> ExportSection::Export::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Export"sv);
auto name = parse_name(stream);
if (name.is_error())
return name.error();
auto tag_or_error = stream.read_value<u8>();
if (tag_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto tag = tag_or_error.release_value();
size_t index;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, index))
return with_eof_check(stream, ParseError::ExpectedIndex);
switch (tag) {
case Constants::extern_function_tag:
return Export { name.release_value(), ExportDesc { FunctionIndex { index } } };
case Constants::extern_table_tag:
return Export { name.release_value(), ExportDesc { TableIndex { index } } };
case Constants::extern_memory_tag:
return Export { name.release_value(), ExportDesc { MemoryIndex { index } } };
case Constants::extern_global_tag:
return Export { name.release_value(), ExportDesc { GlobalIndex { index } } };
default:
return with_eof_check(stream, ParseError::InvalidTag);
}
}
ParseResult<ExportSection> ExportSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("ExportSection"sv);
auto result = parse_vector<Export>(stream);
if (result.is_error())
return result.error();
return ExportSection { result.release_value() };
}
ParseResult<StartSection::StartFunction> StartSection::StartFunction::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("StartFunction"sv);
auto index = GenericIndexParser<FunctionIndex>::parse(stream);
if (index.is_error())
return index.error();
return StartFunction { index.release_value() };
}
ParseResult<StartSection> StartSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("StartSection"sv);
auto result = StartFunction::parse(stream);
if (result.is_error())
return result.error();
return StartSection { result.release_value() };
}
ParseResult<ElementSection::SegmentType0> ElementSection::SegmentType0::parse(Core::Stream::Stream& stream)
{
auto expression = Expression::parse(stream);
if (expression.is_error())
return expression.error();
auto indices = parse_vector<GenericIndexParser<FunctionIndex>>(stream);
if (indices.is_error())
return indices.error();
return SegmentType0 { indices.release_value(), Active { 0, expression.release_value() } };
}
ParseResult<ElementSection::SegmentType1> ElementSection::SegmentType1::parse(Core::Stream::Stream& stream)
{
auto kind_or_error = stream.read_value<u8>();
if (kind_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto kind = kind_or_error.release_value();
if (kind != 0)
return ParseError::InvalidTag;
auto indices = parse_vector<GenericIndexParser<FunctionIndex>>(stream);
if (indices.is_error())
return indices.error();
return SegmentType1 { indices.release_value() };
}
ParseResult<ElementSection::SegmentType2> ElementSection::SegmentType2::parse(Core::Stream::Stream& stream)
{
dbgln("Type 2");
(void)stream;
return ParseError::NotImplemented;
}
ParseResult<ElementSection::SegmentType3> ElementSection::SegmentType3::parse(Core::Stream::Stream& stream)
{
dbgln("Type 3");
(void)stream;
return ParseError::NotImplemented;
}
ParseResult<ElementSection::SegmentType4> ElementSection::SegmentType4::parse(Core::Stream::Stream& stream)
{
dbgln("Type 4");
(void)stream;
return ParseError::NotImplemented;
}
ParseResult<ElementSection::SegmentType5> ElementSection::SegmentType5::parse(Core::Stream::Stream& stream)
{
dbgln("Type 5");
(void)stream;
return ParseError::NotImplemented;
}
ParseResult<ElementSection::SegmentType6> ElementSection::SegmentType6::parse(Core::Stream::Stream& stream)
{
dbgln("Type 6");
(void)stream;
return ParseError::NotImplemented;
}
ParseResult<ElementSection::SegmentType7> ElementSection::SegmentType7::parse(Core::Stream::Stream& stream)
{
dbgln("Type 7");
(void)stream;
return ParseError::NotImplemented;
}
ParseResult<ElementSection::Element> ElementSection::Element::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Element"sv);
auto tag_or_error = stream.read_value<u8>();
if (tag_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto tag = tag_or_error.release_value();
switch (tag) {
case 0x00:
if (auto result = SegmentType0::parse(stream); result.is_error()) {
return result.error();
} else {
Vector<Instruction> instructions;
for (auto& index : result.value().function_indices)
instructions.empend(Instructions::ref_func, index);
return Element { ValueType(ValueType::FunctionReference), { Expression { move(instructions) } }, move(result.value().mode) };
}
case 0x01:
if (auto result = SegmentType1::parse(stream); result.is_error()) {
return result.error();
} else {
Vector<Instruction> instructions;
for (auto& index : result.value().function_indices)
instructions.empend(Instructions::ref_func, index);
return Element { ValueType(ValueType::FunctionReference), { Expression { move(instructions) } }, Passive {} };
}
case 0x02:
if (auto result = SegmentType2::parse(stream); result.is_error()) {
return result.error();
} else {
return ParseError::NotImplemented;
}
case 0x03:
if (auto result = SegmentType3::parse(stream); result.is_error()) {
return result.error();
} else {
return ParseError::NotImplemented;
}
case 0x04:
if (auto result = SegmentType4::parse(stream); result.is_error()) {
return result.error();
} else {
return ParseError::NotImplemented;
}
case 0x05:
if (auto result = SegmentType5::parse(stream); result.is_error()) {
return result.error();
} else {
return ParseError::NotImplemented;
}
case 0x06:
if (auto result = SegmentType6::parse(stream); result.is_error()) {
return result.error();
} else {
return ParseError::NotImplemented;
}
case 0x07:
if (auto result = SegmentType7::parse(stream); result.is_error()) {
return result.error();
} else {
return ParseError::NotImplemented;
}
default:
return ParseError::InvalidTag;
}
}
ParseResult<ElementSection> ElementSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("ElementSection"sv);
auto result = parse_vector<Element>(stream);
if (result.is_error())
return result.error();
return ElementSection { result.release_value() };
}
ParseResult<Locals> Locals::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Locals"sv);
size_t count;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, count))
return with_eof_check(stream, ParseError::InvalidSize);
if (count > Constants::max_allowed_function_locals_per_type)
return with_eof_check(stream, ParseError::HugeAllocationRequested);
auto type = ValueType::parse(stream);
if (type.is_error())
return type.error();
return Locals { static_cast<u32>(count), type.release_value() };
}
ParseResult<CodeSection::Func> CodeSection::Func::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Func"sv);
auto locals = parse_vector<Locals>(stream);
if (locals.is_error())
return locals.error();
auto body = Expression::parse(stream);
if (body.is_error())
return body.error();
return Func { locals.release_value(), body.release_value() };
}
ParseResult<CodeSection::Code> CodeSection::Code::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Code"sv);
size_t size;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, size))
return with_eof_check(stream, ParseError::InvalidSize);
auto constrained_stream = ConstrainedStream { stream, size };
auto func = Func::parse(constrained_stream);
if (func.is_error())
return func.error();
return Code { static_cast<u32>(size), func.release_value() };
}
ParseResult<CodeSection> CodeSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("CodeSection"sv);
auto result = parse_vector<Code>(stream);
if (result.is_error())
return result.error();
return CodeSection { result.release_value() };
}
ParseResult<DataSection::Data> DataSection::Data::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Data"sv);
auto tag_or_error = stream.read_value<u8>();
if (tag_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedKindTag);
auto tag = tag_or_error.release_value();
if (tag > 0x02)
return with_eof_check(stream, ParseError::InvalidTag);
if (tag == 0x00) {
auto expr = Expression::parse(stream);
if (expr.is_error())
return expr.error();
auto init = parse_vector<u8>(stream);
if (init.is_error())
return init.error();
return Data { Active { init.release_value(), { 0 }, expr.release_value() } };
}
if (tag == 0x01) {
auto init = parse_vector<u8>(stream);
if (init.is_error())
return init.error();
return Data { Passive { init.release_value() } };
}
if (tag == 0x02) {
auto index = GenericIndexParser<MemoryIndex>::parse(stream);
if (index.is_error())
return index.error();
auto expr = Expression::parse(stream);
if (expr.is_error())
return expr.error();
auto init = parse_vector<u8>(stream);
if (init.is_error())
return init.error();
return Data { Active { init.release_value(), index.release_value(), expr.release_value() } };
}
VERIFY_NOT_REACHED();
}
ParseResult<DataSection> DataSection::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("DataSection"sv);
auto data = parse_vector<Data>(stream);
if (data.is_error())
return data.error();
return DataSection { data.release_value() };
}
ParseResult<DataCountSection> DataCountSection::parse([[maybe_unused]] Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("DataCountSection"sv);
u32 value;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, value)) {
if (stream.is_eof()) {
// The section simply didn't contain anything.
return DataCountSection { {} };
}
return ParseError::ExpectedSize;
}
return DataCountSection { value };
}
ParseResult<Module> Module::parse(Core::Stream::Stream& stream)
{
ScopeLogger<WASM_BINPARSER_DEBUG> logger("Module"sv);
u8 buf[4];
if (stream.read_entire_buffer({ buf, 4 }).is_error())
return with_eof_check(stream, ParseError::InvalidInput);
if (Bytes { buf, 4 } != wasm_magic.span())
return with_eof_check(stream, ParseError::InvalidModuleMagic);
if (stream.read_entire_buffer({ buf, 4 }).is_error())
return with_eof_check(stream, ParseError::InvalidInput);
if (Bytes { buf, 4 } != wasm_version.span())
return with_eof_check(stream, ParseError::InvalidModuleVersion);
Vector<AnySection> sections;
for (;;) {
auto section_id_or_error = stream.read_value<u8>();
if (stream.is_eof())
break;
if (section_id_or_error.is_error())
return with_eof_check(stream, ParseError::ExpectedIndex);
auto section_id = section_id_or_error.release_value();
size_t section_size;
Core::Stream::WrapInAKInputStream wrapped_stream { stream };
if (!LEB128::read_unsigned(wrapped_stream, section_size))
return with_eof_check(stream, ParseError::ExpectedSize);
auto section_stream = ConstrainedStream { stream, section_size };
switch (section_id) {
case CustomSection::section_id:
sections.append(TRY(CustomSection::parse(section_stream)));
continue;
case TypeSection::section_id:
sections.append(TRY(TypeSection::parse(section_stream)));
continue;
case ImportSection::section_id:
sections.append(TRY(ImportSection::parse(section_stream)));
continue;
case FunctionSection::section_id:
sections.append(TRY(FunctionSection::parse(section_stream)));
continue;
case TableSection::section_id:
sections.append(TRY(TableSection::parse(section_stream)));
continue;
case MemorySection::section_id:
sections.append(TRY(MemorySection::parse(section_stream)));
continue;
case GlobalSection::section_id:
sections.append(TRY(GlobalSection::parse(section_stream)));
continue;
case ExportSection::section_id:
sections.append(TRY(ExportSection::parse(section_stream)));
continue;
case StartSection::section_id:
sections.append(TRY(StartSection::parse(section_stream)));
continue;
case ElementSection::section_id:
sections.append(TRY(ElementSection::parse(section_stream)));
continue;
case CodeSection::section_id:
sections.append(TRY(CodeSection::parse(section_stream)));
continue;
case DataSection::section_id:
sections.append(TRY(DataSection::parse(section_stream)));
continue;
case DataCountSection::section_id:
sections.append(TRY(DataCountSection::parse(section_stream)));
continue;
default:
return with_eof_check(stream, ParseError::InvalidIndex);
}
}
return Module { move(sections) };
}
bool Module::populate_sections()
{
auto is_ok = true;
FunctionSection const* function_section { nullptr };
for_each_section_of_type<FunctionSection>([&](FunctionSection const& section) { function_section = &section; });
for_each_section_of_type<CodeSection>([&](CodeSection const& section) {
if (!function_section) {
is_ok = false;
return;
}
size_t index = 0;
for (auto& entry : section.functions()) {
if (function_section->types().size() <= index) {
is_ok = false;
return;
}
auto& type_index = function_section->types()[index];
Vector<ValueType> locals;
for (auto& local : entry.func().locals()) {
for (size_t i = 0; i < local.n(); ++i)
locals.append(local.type());
}
m_functions.empend(type_index, move(locals), entry.func().body());
++index;
}
});
return is_ok;
}
DeprecatedString parse_error_to_deprecated_string(ParseError error)
{
switch (error) {
case ParseError::UnexpectedEof:
return "Unexpected end-of-file";
case ParseError::ExpectedIndex:
return "Expected a valid index value";
case ParseError::ExpectedKindTag:
return "Expected a valid kind tag";
case ParseError::ExpectedSize:
return "Expected a valid LEB128-encoded size";
case ParseError::ExpectedValueOrTerminator:
return "Expected either a terminator or a value";
case ParseError::InvalidIndex:
return "An index parsed was semantically invalid";
case ParseError::InvalidInput:
return "Input data contained invalid bytes";
case ParseError::InvalidModuleMagic:
return "Incorrect module magic (did not match \\0asm)";
case ParseError::InvalidModuleVersion:
return "Incorrect module version";
case ParseError::InvalidSize:
return "A parsed size did not make sense in context";
case ParseError::InvalidTag:
return "A parsed tag did not make sense in context";
case ParseError::InvalidType:
return "A parsed type did not make sense in context";
case ParseError::NotImplemented:
return "The parser encountered an unimplemented feature";
case ParseError::HugeAllocationRequested:
return "Parsing caused an attempt to allocate a very big chunk of memory, likely malformed data";
case ParseError::OutOfMemory:
return "The parser hit an OOM condition";
case ParseError::ExpectedFloatingImmediate:
return "Expected a floating point immediate";
case ParseError::ExpectedSignedImmediate:
return "Expected a signed integer immediate";
case ParseError::InvalidImmediate:
return "A parsed instruction immediate was invalid for the instruction it was used for";
case ParseError::UnknownInstruction:
return "A parsed instruction was not known to this parser";
}
return "Unknown error";
}
}