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/*
* Copyright 2016 WebAssembly Community Group participants
*
* 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
*
*
* 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 "wabt/binary-writer.h"
#include <cassert>
#include <cmath>
#include <cstdarg>
#include <cstdint>
#include <cstdio>
#include <set>
#include <string_view>
#include <vector>
#include "wabt/config.h"
#include "wabt/binary.h"
#include "wabt/cast.h"
#include "wabt/expr-visitor.h"
#include "wabt/ir.h"
#include "wabt/leb128.h"
#include "wabt/stream.h"
#define PRINT_HEADER_NO_INDEX -1
#define MAX_U32_LEB128_BYTES 5
namespace wabt {
void WriteStr(Stream* stream,
std::string_view s,
const char* desc,
PrintChars print_chars) {
WriteU32Leb128(stream, s.length(), "string length");
stream->WriteData(s.data(), s.length(), desc, print_chars);
}
void WriteOpcode(Stream* stream, Opcode opcode) {
if (opcode.HasPrefix()) {
stream->WriteU8(opcode.GetPrefix(), "prefix");
WriteU32Leb128(stream, opcode.GetCode(), opcode.GetName());
} else {
stream->WriteU8(opcode.GetCode(), opcode.GetName());
}
}
void WriteType(Stream* stream, Type type, const char* desc) {
WriteS32Leb128(stream, type, desc ? desc : type.GetName().c_str());
if (type.IsReferenceWithIndex()) {
WriteS32Leb128(stream, type.GetReferenceIndex(),
desc ? desc : type.GetName().c_str());
}
}
void WriteLimits(Stream* stream, const Limits* limits) {
uint32_t flags = limits->has_max ? WABT_BINARY_LIMITS_HAS_MAX_FLAG : 0;
flags |= limits->is_shared ? WABT_BINARY_LIMITS_IS_SHARED_FLAG : 0;
flags |= limits->is_64 ? WABT_BINARY_LIMITS_IS_64_FLAG : 0;
WriteU32Leb128(stream, flags, "limits: flags");
if (limits->is_64) {
WriteU64Leb128(stream, limits->initial, "limits: initial");
if (limits->has_max) {
WriteU64Leb128(stream, limits->max, "limits: max");
}
} else {
WriteU32Leb128(stream, limits->initial, "limits: initial");
if (limits->has_max) {
WriteU32Leb128(stream, limits->max, "limits: max");
}
}
}
void WriteDebugName(Stream* stream, std::string_view name, const char* desc) {
std::string_view stripped_name = name;
if (!stripped_name.empty()) {
// Strip leading $ from name
assert(stripped_name.front() == '$');
stripped_name.remove_prefix(1);
}
WriteStr(stream, stripped_name, desc, PrintChars::Yes);
}
namespace {
/* TODO(binji): better leb size guess. Some sections we know will only be 1
byte, but others we can be fairly certain will be larger. */
constexpr size_t LEB_SECTION_SIZE_GUESS = 1;
#define ALLOC_FAILURE \
fprintf(stderr, "%s:%d: allocation failed\n", __FILE__, __LINE__)
struct RelocSection {
RelocSection(const char* name, Index index)
: name(name), section_index(index) {}
const char* name;
Index section_index;
std::vector<Reloc> relocations;
};
class Symbol {
public:
struct Function {
static const SymbolType type = SymbolType::Function;
Index index;
};
struct Data {
static const SymbolType type = SymbolType::Data;
Index index;
Offset offset;
Address size;
};
struct Global {
static const SymbolType type = SymbolType::Global;
Index index;
};
struct Section {
static const SymbolType type = SymbolType::Section;
Index section;
};
struct Tag {
static const SymbolType type = SymbolType::Tag;
Index index;
};
struct Table {
static const SymbolType type = SymbolType::Table;
Index index;
};
private:
SymbolType type_;
std::string_view name_;
uint8_t flags_;
union {
Function function_;
Data data_;
Global global_;
Section section_;
Tag tag_;
Table table_;
};
public:
Symbol(const std::string_view& name, uint8_t flags, const Function& f)
: type_(Function::type), name_(name), flags_(flags), function_(f) {}
Symbol(const std::string_view& name, uint8_t flags, const Data& d)
: type_(Data::type), name_(name), flags_(flags), data_(d) {}
Symbol(const std::string_view& name, uint8_t flags, const Global& g)
: type_(Global::type), name_(name), flags_(flags), global_(g) {}
Symbol(const std::string_view& name, uint8_t flags, const Section& s)
: type_(Section::type), name_(name), flags_(flags), section_(s) {}
Symbol(const std::string_view& name, uint8_t flags, const Tag& e)
: type_(Tag::type), name_(name), flags_(flags), tag_(e) {}
Symbol(const std::string_view& name, uint8_t flags, const Table& t)
: type_(Table::type), name_(name), flags_(flags), table_(t) {}
SymbolType type() const { return type_; }
const std::string_view& name() const { return name_; }
uint8_t flags() const { return flags_; }
SymbolVisibility visibility() const {
return static_cast<SymbolVisibility>(flags() & WABT_SYMBOL_MASK_VISIBILITY);
}
SymbolBinding binding() const {
return static_cast<SymbolBinding>(flags() & WABT_SYMBOL_MASK_BINDING);
}
bool undefined() const { return flags() & WABT_SYMBOL_FLAG_UNDEFINED; }
bool defined() const { return !undefined(); }
bool exported() const { return flags() & WABT_SYMBOL_FLAG_EXPORTED; }
bool explicit_name() const {
return flags() & WABT_SYMBOL_FLAG_EXPLICIT_NAME;
}
bool no_strip() const { return flags() & WABT_SYMBOL_FLAG_NO_STRIP; }
bool IsFunction() const { return type() == Function::type; }
bool IsData() const { return type() == Data::type; }
bool IsGlobal() const { return type() == Global::type; }
bool IsSection() const { return type() == Section::type; }
bool IsTag() const { return type() == Tag::type; }
bool IsTable() const { return type() == Table::type; }
const Function& AsFunction() const {
assert(IsFunction());
return function_;
}
const Data& AsData() const {
assert(IsData());
return data_;
}
const Global& AsGlobal() const {
assert(IsGlobal());
return global_;
}
const Section& AsSection() const {
assert(IsSection());
return section_;
}
const Tag& AsTag() const {
assert(IsTag());
return tag_;
}
const Table& AsTable() const {
assert(IsTable());
return table_;
}
};
class SymbolTable {
WABT_DISALLOW_COPY_AND_ASSIGN(SymbolTable);
std::vector<Symbol> symbols_;
std::vector<Index> functions_;
std::vector<Index> tables_;
std::vector<Index> globals_;
std::set<std::string_view> seen_names_;
Result EnsureUnique(const std::string_view& name) {
if (seen_names_.count(name)) {
fprintf(stderr,
"error: duplicate symbol when writing relocatable "
"binary: %s\n",
&name[0]);
return Result::Error;
}
seen_names_.insert(name);
return Result::Ok;
};
template <typename T>
Result AddSymbol(std::vector<Index>* map,
std::string_view name,
bool imported,
bool exported,
T&& sym) {
uint8_t flags = 0;
if (imported) {
flags |= WABT_SYMBOL_FLAG_UNDEFINED;
// Wabt currently has no way for a user to explicitly specify the name of
// an import, so never set the EXPLICIT_NAME flag, and ignore any display
// name fabricated by wabt.
name = std::string_view();
} else {
if (name.empty()) {
// Definitions without a name are local.
flags |= uint8_t(SymbolBinding::Local);
flags |= uint8_t(SymbolVisibility::Hidden);
} else {
// Otherwise, strip the dollar off the name; a definition $foo is
// available for linking as "foo".
assert(name[0] == '$');
name.remove_prefix(1);
}
if (exported) {
CHECK_RESULT(EnsureUnique(name));
flags |= uint8_t(SymbolVisibility::Hidden);
flags |= WABT_SYMBOL_FLAG_NO_STRIP;
}
}
if (exported) {
flags |= WABT_SYMBOL_FLAG_EXPORTED;
}
map->push_back(symbols_.size());
symbols_.emplace_back(name, flags, sym);
return Result::Ok;
};
Index SymbolIndex(const std::vector<Index>& table, Index index) const {
// For well-formed modules, an index into (e.g.) functions_ will always be
// within bounds; the out-of-bounds case here is just to allow --relocatable
// to write known-invalid modules.
return index < table.size() ? table[index] : kInvalidIndex;
}
public:
SymbolTable() {}
Result Populate(const Module* module) {
std::set<Index> exported_funcs;
std::set<Index> exported_globals;
std::set<Index> exported_tags;
std::set<Index> exported_tables;
for (const Export* export_ : module->exports) {
switch (export_->kind) {
case ExternalKind::Func:
exported_funcs.insert(module->GetFuncIndex(export_->var));
break;
case ExternalKind::Table:
exported_tables.insert(module->GetTableIndex(export_->var));
break;
case ExternalKind::Memory:
break;
case ExternalKind::Global:
exported_globals.insert(module->GetGlobalIndex(export_->var));
break;
case ExternalKind::Tag:
exported_tags.insert(module->GetTagIndex(export_->var));
break;
}
}
// We currently only create symbol table entries for function, table, and
// global symbols.
for (size_t i = 0; i < module->funcs.size(); ++i) {
const Func* func = module->funcs[i];
bool imported = i < module->num_func_imports;
bool exported = exported_funcs.count(i);
CHECK_RESULT(AddSymbol(&functions_, func->name, imported, exported,
Symbol::Function{Index(i)}));
}
for (size_t i = 0; i < module->tables.size(); ++i) {
const Table* table = module->tables[i];
bool imported = i < module->num_table_imports;
bool exported = exported_tables.count(i);
CHECK_RESULT(AddSymbol(&tables_, table->name, imported, exported,
Symbol::Table{Index(i)}));
}
for (size_t i = 0; i < module->globals.size(); ++i) {
const Global* global = module->globals[i];
bool imported = i < module->num_global_imports;
bool exported = exported_globals.count(i);
CHECK_RESULT(AddSymbol(&globals_, global->name, imported, exported,
Symbol::Global{Index(i)}));
}
return Result::Ok;
}
const std::vector<Symbol>& symbols() const { return symbols_; }
Index FunctionSymbolIndex(Index index) const {
return SymbolIndex(functions_, index);
}
Index TableSymbolIndex(Index index) const {
return SymbolIndex(tables_, index);
}
Index GlobalSymbolIndex(Index index) const {
return SymbolIndex(globals_, index);
}
};
struct CodeMetadata {
Offset offset;
std::vector<uint8_t> data;
CodeMetadata(Offset offset, std::vector<uint8_t> data)
: offset(offset), data(std::move(data)) {}
};
struct FuncCodeMetadata {
Index func_idx;
std::vector<CodeMetadata> entries;
FuncCodeMetadata(Index func_idx) : func_idx(func_idx) {}
};
struct CodeMetadataSection {
std::vector<FuncCodeMetadata> entries;
};
using CodeMetadataSections =
std::unordered_map<std::string_view, CodeMetadataSection>;
class BinaryWriter {
WABT_DISALLOW_COPY_AND_ASSIGN(BinaryWriter);
public:
BinaryWriter(Stream*,
const WriteBinaryOptions& options,
const Module* module);
Result WriteModule();
private:
void WriteHeader(const char* name, int index);
Offset WriteU32Leb128Space(Offset leb_size_guess, const char* desc);
Offset WriteFixupU32Leb128Size(Offset offset,
Offset leb_size_guess,
const char* desc);
void BeginKnownSection(BinarySection section_code);
void BeginCustomSection(const char* name);
void WriteSectionHeader(const char* desc, BinarySection section_code);
void EndSection();
void BeginSubsection(const char* name);
void EndSubsection();
Index GetLabelVarDepth(const Var* var);
Index GetTagVarDepth(const Var* var);
Index GetLocalIndex(const Func* func, const Var& var);
Index GetSymbolIndex(RelocType reloc_type, Index index);
void AddReloc(RelocType reloc_type, Index index);
void WriteBlockDecl(const BlockDeclaration& decl);
void WriteU32Leb128WithReloc(Index index,
const char* desc,
RelocType reloc_type);
void WriteS32Leb128WithReloc(int32_t value,
const char* desc,
RelocType reloc_type);
void WriteTableNumberWithReloc(Index table_number, const char* desc);
template <typename T>
void WriteLoadStoreExpr(const Func* func, const Expr* expr, const char* desc);
template <typename T>
void WriteSimdLoadStoreLaneExpr(const Func* func,
const Expr* expr,
const char* desc);
void WriteExpr(const Func* func, const Expr* expr);
void WriteExprList(const Func* func, const ExprList& exprs);
void WriteInitExpr(const ExprList& expr);
void WriteFuncLocals(const Func* func, const LocalTypes& local_types);
void WriteFunc(const Func* func);
void WriteTable(const Table* table);
void WriteMemory(const Memory* memory);
void WriteGlobalHeader(const Global* global);
void WriteTagType(const Tag* tag);
void WriteRelocSection(const RelocSection* reloc_section);
void WriteLinkingSection();
template <typename T>
void WriteNames(const std::vector<T*>& elems, NameSectionSubsection type);
void WriteCodeMetadataSections();
Stream* stream_;
const WriteBinaryOptions& options_;
const Module* module_;
SymbolTable symtab_;
std::vector<RelocSection> reloc_sections_;
RelocSection* current_reloc_section_ = nullptr;
Index section_count_ = 0;
size_t last_section_offset_ = 0;
size_t last_section_leb_size_guess_ = 0;
BinarySection last_section_type_ = BinarySection::Invalid;
size_t last_section_payload_offset_ = 0;
size_t last_subsection_offset_ = 0;
size_t last_subsection_leb_size_guess_ = 0;
size_t last_subsection_payload_offset_ = 0;
// Information about the data count section, so it can be removed if it is
// not needed, and relocs relative to the code section patched up.
size_t code_start_ = 0;
size_t data_count_start_ = 0;
size_t data_count_end_ = 0;
bool has_data_segment_instruction_ = false;
CodeMetadataSections code_metadata_sections_;
Offset cur_func_start_offset_;
Index cur_func_index_;
};
static uint8_t log2_u32(uint32_t x) {
uint8_t result = 0;
while (x > 1) {
x >>= 1;
result++;
}
return result;
}
BinaryWriter::BinaryWriter(Stream* stream,
const WriteBinaryOptions& options,
const Module* module)
: stream_(stream), options_(options), module_(module) {}
void BinaryWriter::WriteHeader(const char* name, int index) {
if (stream_->has_log_stream()) {
if (index == PRINT_HEADER_NO_INDEX) {
stream_->log_stream().Writef("; %s\n", name);
} else {
stream_->log_stream().Writef("; %s %d\n", name, index);
}
}
}
/* returns offset of leb128 */
Offset BinaryWriter::WriteU32Leb128Space(Offset leb_size_guess,
const char* desc) {
assert(leb_size_guess <= MAX_U32_LEB128_BYTES);
uint8_t data[MAX_U32_LEB128_BYTES] = {0};
Offset result = stream_->offset();
Offset bytes_to_write =
options_.canonicalize_lebs ? leb_size_guess : MAX_U32_LEB128_BYTES;
stream_->WriteData(data, bytes_to_write, desc);
return result;
}
Offset BinaryWriter::WriteFixupU32Leb128Size(Offset offset,
Offset leb_size_guess,
const char* desc) {
if (options_.canonicalize_lebs) {
Offset size = stream_->offset() - offset - leb_size_guess;
Offset leb_size = U32Leb128Length(size);
Offset delta = leb_size - leb_size_guess;
if (delta != 0) {
Offset src_offset = offset + leb_size_guess;
Offset dst_offset = offset + leb_size;
stream_->MoveData(dst_offset, src_offset, size);
}
WriteU32Leb128At(stream_, offset, size, desc);
stream_->AddOffset(delta);
return delta;
} else {
Offset size = stream_->offset() - offset - MAX_U32_LEB128_BYTES;
WriteFixedU32Leb128At(stream_, offset, size, desc);
return 0;
}
}
void BinaryWriter::WriteBlockDecl(const BlockDeclaration& decl) {
if (decl.sig.GetNumParams() == 0 && decl.sig.GetNumResults() <= 1) {
if (decl.sig.GetNumResults() == 0) {
WriteType(stream_, Type::Void);
} else if (decl.sig.GetNumResults() == 1) {
WriteType(stream_, decl.sig.GetResultType(0));
}
return;
}
Index index = decl.has_func_type ? module_->GetFuncTypeIndex(decl.type_var)
: module_->GetFuncTypeIndex(decl.sig);
assert(index != kInvalidIndex);
WriteS32Leb128WithReloc(index, "block type function index",
RelocType::TypeIndexLEB);
}
void BinaryWriter::WriteSectionHeader(const char* desc,
BinarySection section_code) {
assert(last_section_leb_size_guess_ == 0);
WriteHeader(desc, PRINT_HEADER_NO_INDEX);
stream_->WriteU8Enum(section_code, "section code");
last_section_type_ = section_code;
last_section_leb_size_guess_ = LEB_SECTION_SIZE_GUESS;
last_section_offset_ =
WriteU32Leb128Space(LEB_SECTION_SIZE_GUESS, "section size (guess)");
last_section_payload_offset_ = stream_->offset();
}
void BinaryWriter::BeginKnownSection(BinarySection section_code) {
char desc[100];
wabt_snprintf(desc, sizeof(desc), "section \"%s\" (%u)",
GetSectionName(section_code),
static_cast<unsigned>(section_code));
WriteSectionHeader(desc, section_code);
}
void BinaryWriter::BeginCustomSection(const char* name) {
char desc[100];
wabt_snprintf(desc, sizeof(desc), "section \"%s\"", name);
WriteSectionHeader(desc, BinarySection::Custom);
WriteStr(stream_, name, "custom section name", PrintChars::Yes);
}
void BinaryWriter::EndSection() {
assert(last_section_leb_size_guess_ != 0);
WriteFixupU32Leb128Size(last_section_offset_, last_section_leb_size_guess_,
"FIXUP section size");
last_section_leb_size_guess_ = 0;
section_count_++;
}
void BinaryWriter::BeginSubsection(const char* name) {
assert(last_subsection_leb_size_guess_ == 0);
last_subsection_leb_size_guess_ = LEB_SECTION_SIZE_GUESS;
last_subsection_offset_ =
WriteU32Leb128Space(LEB_SECTION_SIZE_GUESS, "subsection size (guess)");
last_subsection_payload_offset_ = stream_->offset();
}
void BinaryWriter::EndSubsection() {
assert(last_subsection_leb_size_guess_ != 0);
WriteFixupU32Leb128Size(last_subsection_offset_,
last_subsection_leb_size_guess_,
"FIXUP subsection size");
last_subsection_leb_size_guess_ = 0;
}
Index BinaryWriter::GetLabelVarDepth(const Var* var) {
return var->index();
}
Index BinaryWriter::GetTagVarDepth(const Var* var) {
return var->index();
}
Index BinaryWriter::GetSymbolIndex(RelocType reloc_type, Index index) {
switch (reloc_type) {
case RelocType::FuncIndexLEB:
return symtab_.FunctionSymbolIndex(index);
case RelocType::TableNumberLEB:
return symtab_.TableSymbolIndex(index);
case RelocType::GlobalIndexLEB:
return symtab_.GlobalSymbolIndex(index);
case RelocType::TypeIndexLEB:
// Type indexes don't create entries in the symbol table; instead their
// index is used directly.
return index;
default:
fprintf(stderr, "warning: unsupported relocation type: %s\n",
GetRelocTypeName(reloc_type));
return kInvalidIndex;
}
}
void BinaryWriter::AddReloc(RelocType reloc_type, Index index) {
// Add a new reloc section if needed
if (!current_reloc_section_ ||
current_reloc_section_->section_index != section_count_) {
reloc_sections_.emplace_back(GetSectionName(last_section_type_),
section_count_);
current_reloc_section_ = &reloc_sections_.back();
}
// Add a new relocation to the curent reloc section
size_t offset = stream_->offset() - last_section_payload_offset_;
Index symbol_index = GetSymbolIndex(reloc_type, index);
if (symbol_index == kInvalidIndex) {
// The file is invalid, for example a reference to function 42 where only 10
// functions are defined. The user must have already passed --no-check, so
// no extra warning here is needed.
return;
}
current_reloc_section_->relocations.emplace_back(reloc_type, offset,
symbol_index);
}
void BinaryWriter::WriteU32Leb128WithReloc(Index index,
const char* desc,
RelocType reloc_type) {
if (options_.relocatable) {
AddReloc(reloc_type, index);
WriteFixedU32Leb128(stream_, index, desc);
} else {
WriteU32Leb128(stream_, index, desc);
}
}
void BinaryWriter::WriteS32Leb128WithReloc(int32_t value,
const char* desc,
RelocType reloc_type) {
if (options_.relocatable) {
AddReloc(reloc_type, value);
WriteFixedS32Leb128(stream_, value, desc);
} else {
WriteS32Leb128(stream_, value, desc);
}
}
void BinaryWriter::WriteTableNumberWithReloc(Index value, const char* desc) {
// Unless reference types are enabled, all references to tables refer to table
// 0, so no relocs need be emitted when making relocatable binaries.
if (options_.relocatable && options_.features.reference_types_enabled()) {
AddReloc(RelocType::TableNumberLEB, value);
WriteFixedS32Leb128(stream_, value, desc);
} else {
WriteS32Leb128(stream_, value, desc);
}
}
Index BinaryWriter::GetLocalIndex(const Func* func, const Var& var) {
// func can be nullptr when using local.get/local.set/local.tee in an
// init_expr.
if (func) {
return func->GetLocalIndex(var);
} else if (var.is_index()) {
return var.index();
} else {
return kInvalidIndex;
}
}
// TODO(binji): Rename this, it is used for more than loads/stores now.
template <typename T>
void BinaryWriter::WriteLoadStoreExpr(const Func* func,
const Expr* expr,
const char* desc) {
auto* typed_expr = cast<T>(expr);
WriteOpcode(stream_, typed_expr->opcode);
Address align = typed_expr->opcode.GetAlignment(typed_expr->align);
Index memidx = module_->GetMemoryIndex(typed_expr->memidx);
if (memidx != 0) {
stream_->WriteU8(log2_u32(align) | (1 << 6), "alignment");
WriteU32Leb128(stream_, memidx, "memidx");
} else {
stream_->WriteU8(log2_u32(align), "alignment");
}
WriteU32Leb128(stream_, typed_expr->offset, desc);
}
template <typename T>
void BinaryWriter::WriteSimdLoadStoreLaneExpr(const Func* func,
const Expr* expr,
const char* desc) {
WriteLoadStoreExpr<T>(func, expr, desc);
auto* typed_expr = cast<T>(expr);
stream_->WriteU8(static_cast<uint8_t>(typed_expr->val), "Simd Lane literal");
}
void BinaryWriter::WriteExpr(const Func* func, const Expr* expr) {
switch (expr->type()) {
case ExprType::AtomicLoad:
WriteLoadStoreExpr<AtomicLoadExpr>(func, expr, "memory offset");
break;
case ExprType::AtomicRmw:
WriteLoadStoreExpr<AtomicRmwExpr>(func, expr, "memory offset");
break;
case ExprType::AtomicRmwCmpxchg:
WriteLoadStoreExpr<AtomicRmwCmpxchgExpr>(func, expr, "memory offset");
break;
case ExprType::AtomicStore:
WriteLoadStoreExpr<AtomicStoreExpr>(func, expr, "memory offset");
break;
case ExprType::AtomicWait:
WriteLoadStoreExpr<AtomicWaitExpr>(func, expr, "memory offset");
break;
case ExprType::AtomicFence: {
auto* fence_expr = cast<AtomicFenceExpr>(expr);
WriteOpcode(stream_, Opcode::AtomicFence);
WriteU32Leb128(stream_, fence_expr->consistency_model,
"consistency model");
break;
}
case ExprType::AtomicNotify:
WriteLoadStoreExpr<AtomicNotifyExpr>(func, expr, "memory offset");
break;
case ExprType::Binary:
WriteOpcode(stream_, cast<BinaryExpr>(expr)->opcode);
break;
case ExprType::Block:
WriteOpcode(stream_, Opcode::Block);
WriteBlockDecl(cast<BlockExpr>(expr)->block.decl);
WriteExprList(func, cast<BlockExpr>(expr)->block.exprs);
WriteOpcode(stream_, Opcode::End);
break;
case ExprType::Br:
WriteOpcode(stream_, Opcode::Br);
WriteU32Leb128(stream_, GetLabelVarDepth(&cast<BrExpr>(expr)->var),
"break depth");
break;
case ExprType::BrIf:
WriteOpcode(stream_, Opcode::BrIf);
WriteU32Leb128(stream_, GetLabelVarDepth(&cast<BrIfExpr>(expr)->var),
"break depth");
break;
case ExprType::BrTable: {
auto* br_table_expr = cast<BrTableExpr>(expr);
WriteOpcode(stream_, Opcode::BrTable);
WriteU32Leb128(stream_, br_table_expr->targets.size(), "num targets");
Index depth;
for (const Var& var : br_table_expr->targets) {
depth = GetLabelVarDepth(&var);
WriteU32Leb128(stream_, depth, "break depth");
}
depth = GetLabelVarDepth(&br_table_expr->default_target);
WriteU32Leb128(stream_, depth, "break depth for default");
break;
}
case ExprType::Call: {
Index index = module_->GetFuncIndex(cast<CallExpr>(expr)->var);
WriteOpcode(stream_, Opcode::Call);
WriteU32Leb128WithReloc(index, "function index", RelocType::FuncIndexLEB);
break;
}
case ExprType::ReturnCall: {
Index index = module_->GetFuncIndex(cast<ReturnCallExpr>(expr)->var);
WriteOpcode(stream_, Opcode::ReturnCall);
WriteU32Leb128WithReloc(index, "function index", RelocType::FuncIndexLEB);
break;
}
case ExprType::CallIndirect: {
Index sig_index =
module_->GetFuncTypeIndex(cast<CallIndirectExpr>(expr)->decl);
Index table_index =
module_->GetTableIndex(cast<CallIndirectExpr>(expr)->table);
WriteOpcode(stream_, Opcode::CallIndirect);
WriteU32Leb128WithReloc(sig_index, "signature index",
RelocType::TypeIndexLEB);
WriteTableNumberWithReloc(table_index, "table index");
break;
}
case ExprType::CallRef: {
WriteOpcode(stream_, Opcode::CallRef);
break;
}
case ExprType::ReturnCallIndirect: {
Index sig_index =
module_->GetFuncTypeIndex(cast<ReturnCallIndirectExpr>(expr)->decl);
Index table_index =
module_->GetTableIndex(cast<ReturnCallIndirectExpr>(expr)->table);
WriteOpcode(stream_, Opcode::ReturnCallIndirect);
WriteU32Leb128WithReloc(sig_index, "signature index",
RelocType::TypeIndexLEB);
WriteTableNumberWithReloc(table_index, "table index");
break;
}
case ExprType::Compare:
WriteOpcode(stream_, cast<CompareExpr>(expr)->opcode);
break;
case ExprType::Const: {
const Const& const_ = cast<ConstExpr>(expr)->const_;
switch (const_.type()) {
case Type::I32: {
WriteOpcode(stream_, Opcode::I32Const);
WriteS32Leb128(stream_, const_.u32(), "i32 literal");
break;
}
case Type::I64:
WriteOpcode(stream_, Opcode::I64Const);
WriteS64Leb128(stream_, const_.u64(), "i64 literal");
break;
case Type::F32:
WriteOpcode(stream_, Opcode::F32Const);
stream_->WriteU32(const_.f32_bits(), "f32 literal");
break;
case Type::F64:
WriteOpcode(stream_, Opcode::F64Const);
stream_->WriteU64(const_.f64_bits(), "f64 literal");
break;
case Type::V128:
WriteOpcode(stream_, Opcode::V128Const);
stream_->WriteU128(const_.vec128(), "v128 literal");
break;
default:
assert(0);
}
break;
}
case ExprType::Convert:
WriteOpcode(stream_, cast<ConvertExpr>(expr)->opcode);
break;
case ExprType::Drop:
WriteOpcode(stream_, Opcode::Drop);
break;
case ExprType::GlobalGet: {
Index index = module_->GetGlobalIndex(cast<GlobalGetExpr>(expr)->var);
WriteOpcode(stream_, Opcode::GlobalGet);
WriteU32Leb128WithReloc(index, "global index", RelocType::GlobalIndexLEB);
break;
}
case ExprType::GlobalSet: {
Index index = module_->GetGlobalIndex(cast<GlobalSetExpr>(expr)->var);
WriteOpcode(stream_, Opcode::GlobalSet);
WriteU32Leb128WithReloc(index, "global index", RelocType::GlobalIndexLEB);
break;
}
case ExprType::If: {
auto* if_expr = cast<IfExpr>(expr);
WriteOpcode(stream_, Opcode::If);
WriteBlockDecl(if_expr->true_.decl);
WriteExprList(func, if_expr->true_.exprs);
if (!if_expr->false_.empty()) {
WriteOpcode(stream_, Opcode::Else);
WriteExprList(func, if_expr->false_);
}
WriteOpcode(stream_, Opcode::End);
break;
}
case ExprType::Load:
WriteLoadStoreExpr<LoadExpr>(func, expr, "load offset");
break;
case ExprType::LocalGet: {
Index index = GetLocalIndex(func, cast<LocalGetExpr>(expr)->var);
WriteOpcode(stream_, Opcode::LocalGet);
WriteU32Leb128(stream_, index, "local index");
break;
}
case ExprType::LocalSet: {
Index index = GetLocalIndex(func, cast<LocalSetExpr>(expr)->var);
WriteOpcode(stream_, Opcode::LocalSet);
WriteU32Leb128(stream_, index, "local index");
break;
}
case ExprType::LocalTee: {
Index index = GetLocalIndex(func, cast<LocalTeeExpr>(expr)->var);
WriteOpcode(stream_, Opcode::LocalTee);
WriteU32Leb128(stream_, index, "local index");
break;
}
case ExprType::Loop:
WriteOpcode(stream_, Opcode::Loop);
WriteBlockDecl(cast<LoopExpr>(expr)->block.decl);
WriteExprList(func, cast<LoopExpr>(expr)->block.exprs);
WriteOpcode(stream_, Opcode::End);
break;
case ExprType::MemoryCopy: {
Index srcmemidx =
module_->GetMemoryIndex(cast<MemoryCopyExpr>(expr)->srcmemidx);
Index destmemidx =
module_->GetMemoryIndex(cast<MemoryCopyExpr>(expr)->destmemidx);
WriteOpcode(stream_, Opcode::MemoryCopy);
WriteU32Leb128(stream_, srcmemidx, "memory.copy srcmemidx");
WriteU32Leb128(stream_, destmemidx, "memory.copy destmemidx");
break;
}
case ExprType::DataDrop: {
Index index = module_->GetDataSegmentIndex(cast<DataDropExpr>(expr)->var);
WriteOpcode(stream_, Opcode::DataDrop);
WriteU32Leb128(stream_, index, "data.drop segment");
has_data_segment_instruction_ = true;
break;
}
case ExprType::MemoryFill: {
Index memidx =
module_->GetMemoryIndex(cast<MemoryFillExpr>(expr)->memidx);
WriteOpcode(stream_, Opcode::MemoryFill);
WriteU32Leb128(stream_, memidx, "memory.fill memidx");
break;
}
case ExprType::MemoryGrow: {
Index memidx =
module_->GetMemoryIndex(cast<MemoryGrowExpr>(expr)->memidx);
WriteOpcode(stream_, Opcode::MemoryGrow);
WriteU32Leb128(stream_, memidx, "memory.grow memidx");
break;
}
case ExprType::MemoryInit: {
Index index =
module_->GetDataSegmentIndex(cast<MemoryInitExpr>(expr)->var);
Index memidx =
module_->GetMemoryIndex(cast<MemoryInitExpr>(expr)->memidx);
WriteOpcode(stream_, Opcode::MemoryInit);
WriteU32Leb128(stream_, index, "memory.init segment");
WriteU32Leb128(stream_, memidx, "memory.init memidx");
has_data_segment_instruction_ = true;
break;
}
case ExprType::MemorySize: {
Index memidx =
module_->GetMemoryIndex(cast<MemorySizeExpr>(expr)->memidx);
WriteOpcode(stream_, Opcode::MemorySize);
WriteU32Leb128(stream_, memidx, "memory.size memidx");
break;
}
case ExprType::TableCopy: {
auto* copy_expr = cast<TableCopyExpr>(expr);
Index dst = module_->GetTableIndex(copy_expr->dst_table);
Index src = module_->GetTableIndex(copy_expr->src_table);
WriteOpcode(stream_, Opcode::TableCopy);
WriteTableNumberWithReloc(dst, "table.copy dst_table");
WriteTableNumberWithReloc(src, "table.copy src_table");
break;
}
case ExprType::ElemDrop: {
Index index = module_->GetElemSegmentIndex(cast<ElemDropExpr>(expr)->var);
WriteOpcode(stream_, Opcode::ElemDrop);
WriteU32Leb128(stream_, index, "elem.drop segment");
break;
}
case ExprType::TableInit: {
auto* init_expr = cast<TableInitExpr>(expr);
Index table_index = module_->GetTableIndex(init_expr->table_index);
Index segment_index =
module_->GetElemSegmentIndex(init_expr->segment_index);
WriteOpcode(stream_, Opcode::TableInit);
WriteU32Leb128(stream_, segment_index, "table.init segment");
WriteTableNumberWithReloc(table_index, "table.init table");
break;
}
case ExprType::TableGet: {
Index index = module_->GetTableIndex(cast<TableGetExpr>(expr)->var);
WriteOpcode(stream_, Opcode::TableGet);
WriteTableNumberWithReloc(index, "table.get table index");
break;
}
case ExprType::TableSet: {
Index index = module_->GetTableIndex(cast<TableSetExpr>(expr)->var);
WriteOpcode(stream_, Opcode::TableSet);
WriteTableNumberWithReloc(index, "table.set table index");
break;
}
case ExprType::TableGrow: {
Index index = module_->GetTableIndex(cast<TableGrowExpr>(expr)->var);
WriteOpcode(stream_, Opcode::TableGrow);
WriteTableNumberWithReloc(index, "table.grow table index");
break;
}
case ExprType::TableSize: {
Index index = module_->GetTableIndex(cast<TableSizeExpr>(expr)->var);
WriteOpcode(stream_, Opcode::TableSize);
WriteTableNumberWithReloc(index, "table.size table index");
break;
}
case ExprType::TableFill: {
Index index = module_->GetTableIndex(cast<TableFillExpr>(expr)->var);
WriteOpcode(stream_, Opcode::TableFill);
WriteTableNumberWithReloc(index, "table.fill table index");
break;
}
case ExprType::RefFunc: {
WriteOpcode(stream_, Opcode::RefFunc);
Index index = module_->GetFuncIndex(cast<RefFuncExpr>(expr)->var);
WriteU32Leb128WithReloc(index, "function index", RelocType::FuncIndexLEB);
break;
}
case ExprType::RefNull: {
WriteOpcode(stream_, Opcode::RefNull);
WriteType(stream_, cast<RefNullExpr>(expr)->type, "ref.null type");
break;
}
case ExprType::RefIsNull:
WriteOpcode(stream_, Opcode::RefIsNull);
break;
case ExprType::Nop:
WriteOpcode(stream_, Opcode::Nop);
break;
case ExprType::Rethrow:
WriteOpcode(stream_, Opcode::Rethrow);
WriteU32Leb128(stream_, GetLabelVarDepth(&cast<RethrowExpr>(expr)->var),
"rethrow depth");
break;
case ExprType::Return:
WriteOpcode(stream_, Opcode::Return);
break;
case ExprType::Select: {
auto* select_expr = cast<SelectExpr>(expr);
if (select_expr->result_type.empty()) {
WriteOpcode(stream_, Opcode::Select);
} else {
WriteOpcode(stream_, Opcode::SelectT);
WriteU32Leb128(stream_, select_expr->result_type.size(),
"num result types");
for (Type t : select_expr->result_type) {
WriteType(stream_, t, "result type");
}
}
break;
}
case ExprType::Store:
WriteLoadStoreExpr<StoreExpr>(func, expr, "store offset");
break;
case ExprType::Throw:
WriteOpcode(stream_, Opcode::Throw);
WriteU32Leb128(stream_, GetTagVarDepth(&cast<ThrowExpr>(expr)->var),
"throw tag");
break;
case ExprType::Try: {
auto* try_expr = cast<TryExpr>(expr);
WriteOpcode(stream_, Opcode::Try);
WriteBlockDecl(try_expr->block.decl);
WriteExprList(func, try_expr->block.exprs);
switch (try_expr->kind) {
case TryKind::Catch:
for (const Catch& catch_ : try_expr->catches) {
if (catch_.IsCatchAll()) {
WriteOpcode(stream_, Opcode::CatchAll);
} else {
WriteOpcode(stream_, Opcode::Catch);
WriteU32Leb128(stream_, GetTagVarDepth(&catch_.var), "catch tag");
}
WriteExprList(func, catch_.exprs);
}
WriteOpcode(stream_, Opcode::End);
break;
case TryKind::Delegate:
WriteOpcode(stream_, Opcode::Delegate);
WriteU32Leb128(stream_, GetLabelVarDepth(&try_expr->delegate_target),
"delegate depth");
break;
case TryKind::Plain:
WriteOpcode(stream_, Opcode::End);
break;
}
break;
}
case ExprType::Unary:
WriteOpcode(stream_, cast<UnaryExpr>(expr)->opcode);
break;
case ExprType::Ternary:
WriteOpcode(stream_, cast<TernaryExpr>(expr)->opcode);
break;
case ExprType::SimdLaneOp: {
const Opcode opcode = cast<SimdLaneOpExpr>(expr)->opcode;
WriteOpcode(stream_, opcode);
stream_->WriteU8(static_cast<uint8_t>(cast<SimdLaneOpExpr>(expr)->val),
"Simd Lane literal");
break;
}
case ExprType::SimdLoadLane: {
WriteSimdLoadStoreLaneExpr<SimdLoadLaneExpr>(func, expr, "load offset");
break;
}
case ExprType::SimdStoreLane: {
WriteSimdLoadStoreLaneExpr<SimdStoreLaneExpr>(func, expr, "store offset");
break;
}
case ExprType::SimdShuffleOp: {
const Opcode opcode = cast<SimdShuffleOpExpr>(expr)->opcode;
WriteOpcode(stream_, opcode);
stream_->WriteU128(cast<SimdShuffleOpExpr>(expr)->val,
"Simd Lane[16] literal");
break;
}
case ExprType::LoadSplat:
WriteLoadStoreExpr<LoadSplatExpr>(func, expr, "load offset");
break;
case ExprType::LoadZero:
WriteLoadStoreExpr<LoadZeroExpr>(func, expr, "load offset");
break;
case ExprType::Unreachable:
WriteOpcode(stream_, Opcode::Unreachable);
break;
case ExprType::CodeMetadata: {
auto* meta_expr = cast<CodeMetadataExpr>(expr);
auto& s = code_metadata_sections_[meta_expr->name];
if (s.entries.empty() || s.entries.back().func_idx != cur_func_index_) {
s.entries.emplace_back(cur_func_index_);
}
auto& a = s.entries.back();
Offset code_offset = stream_->offset() - cur_func_start_offset_;
a.entries.emplace_back(code_offset, meta_expr->data);
break;
}
}
}
void BinaryWriter::WriteExprList(const Func* func, const ExprList& exprs) {
for (const Expr& expr : exprs) {
WriteExpr(func, &expr);
}
}
void BinaryWriter::WriteInitExpr(const ExprList& expr) {
WriteExprList(nullptr, expr);
WriteOpcode(stream_, Opcode::End);
}
void BinaryWriter::WriteFuncLocals(const Func* func,
const LocalTypes& local_types) {
if (local_types.size() == 0) {
WriteU32Leb128(stream_, 0, "local decl count");
return;
}
Index local_decl_count = local_types.decls().size();
WriteU32Leb128(stream_, local_decl_count, "local decl count");
for (auto decl : local_types.decls()) {
WriteU32Leb128(stream_, decl.second, "local type count");
WriteType(stream_, decl.first);
}
}
void BinaryWriter::WriteFunc(const Func* func) {
WriteFuncLocals(func, func->local_types);
WriteExprList(func, func->exprs);
WriteOpcode(stream_, Opcode::End);
}
void BinaryWriter::WriteTable(const Table* table) {
WriteType(stream_, table->elem_type);
WriteLimits(stream_, &table->elem_limits);
}
void BinaryWriter::WriteMemory(const Memory* memory) {
WriteLimits(stream_, &memory->page_limits);
}
void BinaryWriter::WriteGlobalHeader(const Global* global) {
WriteType(stream_, global->type);
stream_->WriteU8(global->mutable_, "global mutability");
}
void BinaryWriter::WriteTagType(const Tag* tag) {
stream_->WriteU8(0, "tag attribute");
WriteU32Leb128(stream_, module_->GetFuncTypeIndex(tag->decl),
"tag signature index");
}
void BinaryWriter::WriteRelocSection(const RelocSection* reloc_section) {
char section_name[128];
wabt_snprintf(section_name, sizeof(section_name), "%s.%s",
WABT_BINARY_SECTION_RELOC, reloc_section->name);
BeginCustomSection(section_name);
WriteU32Leb128(stream_, reloc_section->section_index, "reloc section index");
const std::vector<Reloc>& relocs = reloc_section->relocations;
WriteU32Leb128(stream_, relocs.size(), "num relocs");
for (const Reloc& reloc : relocs) {
WriteU32Leb128(stream_, reloc.type, "reloc type");
WriteU32Leb128(stream_, reloc.offset, "reloc offset");
WriteU32Leb128(stream_, reloc.index, "reloc index");
switch (reloc.type) {
case RelocType::MemoryAddressLEB:
case RelocType::MemoryAddressLEB64:
case RelocType::MemoryAddressSLEB:
case RelocType::MemoryAddressSLEB64:
case RelocType::MemoryAddressRelSLEB:
case RelocType::MemoryAddressRelSLEB64:
case RelocType::MemoryAddressI32:
case RelocType::MemoryAddressI64:
case RelocType::FunctionOffsetI32:
case RelocType::SectionOffsetI32:
case RelocType::MemoryAddressTLSSLEB:
case RelocType::MemoryAddressTLSI32:
WriteU32Leb128(stream_, reloc.addend, "reloc addend");
break;
case RelocType::FuncIndexLEB:
case RelocType::TableIndexSLEB:
case RelocType::TableIndexSLEB64:
case RelocType::TableIndexI32:
case RelocType::TableIndexI64:
case RelocType::TypeIndexLEB:
case RelocType::GlobalIndexLEB:
case RelocType::TagIndexLEB:
case RelocType::TableIndexRelSLEB:
case RelocType::TableNumberLEB:
break;
default:
fprintf(stderr, "warning: unsupported relocation type: %s\n",
GetRelocTypeName(reloc.type));
}
}
EndSection();
}
void BinaryWriter::WriteLinkingSection() {
BeginCustomSection(WABT_BINARY_SECTION_LINKING);
WriteU32Leb128(stream_, 2, "metadata version");
const std::vector<Symbol>& symbols = symtab_.symbols();
if (symbols.size()) {
stream_->WriteU8Enum(LinkingEntryType::SymbolTable, "symbol table");
BeginSubsection("symbol table");
WriteU32Leb128(stream_, symbols.size(), "num symbols");
for (const Symbol& sym : symbols) {
stream_->WriteU8Enum(sym.type(), "symbol type");
WriteU32Leb128(stream_, sym.flags(), "symbol flags");
switch (sym.type()) {
case SymbolType::Function:
WriteU32Leb128(stream_, sym.AsFunction().index, "function index");
if (sym.defined() || sym.explicit_name()) {
WriteStr(stream_, sym.name(), "function name", PrintChars::Yes);
}
break;
case SymbolType::Data:
WriteStr(stream_, sym.name(), "data name", PrintChars::Yes);
if (sym.defined()) {
WriteU32Leb128(stream_, sym.AsData().index, "data index");
WriteU32Leb128(stream_, sym.AsData().offset, "data offset");
WriteU32Leb128(stream_, sym.AsData().size, "data size");
}
break;
case SymbolType::Global:
WriteU32Leb128(stream_, sym.AsGlobal().index, "global index");
if (sym.defined() || sym.explicit_name()) {
WriteStr(stream_, sym.name(), "global name", PrintChars::Yes);
}
break;
case SymbolType::Section:
WriteU32Leb128(stream_, sym.AsSection().section, "section index");
break;
case SymbolType::Tag:
WriteU32Leb128(stream_, sym.AsTag().index, "tag index");
if (sym.defined() || sym.explicit_name()) {
WriteStr(stream_, sym.name(), "tag name", PrintChars::Yes);
}
break;
case SymbolType::Table:
WriteU32Leb128(stream_, sym.AsTable().index, "table index");
if (sym.defined() || sym.explicit_name()) {
WriteStr(stream_, sym.name(), "table name", PrintChars::Yes);
}
break;
}
}
EndSubsection();
}
EndSection();
}
template <typename T>
void BinaryWriter::WriteNames(const std::vector<T*>& elems,
NameSectionSubsection type) {
size_t num_named_elems = 0;
for (const T* elem : elems) {
if (!elem->name.empty()) {
num_named_elems++;
}
}
if (!num_named_elems) {
return;
}
WriteU32Leb128(stream_, type, "name subsection type");
BeginSubsection("name subsection");
char desc[100];
WriteU32Leb128(stream_, num_named_elems, "num names");
for (size_t i = 0; i < elems.size(); ++i) {
const T* elem = elems[i];
if (elem->name.empty()) {
continue;
}
WriteU32Leb128(stream_, i, "elem index");
wabt_snprintf(desc, sizeof(desc), "elem name %" PRIzd, i);
WriteDebugName(stream_, elem->name, desc);
}
EndSubsection();
}
Result BinaryWriter::WriteModule() {
stream_->WriteU32(WABT_BINARY_MAGIC, "WASM_BINARY_MAGIC");
stream_->WriteU32(WABT_BINARY_VERSION, "WASM_BINARY_VERSION");
if (options_.relocatable) {
CHECK_RESULT(symtab_.Populate(module_));
}
if (module_->types.size()) {
BeginKnownSection(BinarySection::Type);
WriteU32Leb128(stream_, module_->types.size(), "num types");
for (size_t i = 0; i < module_->types.size(); ++i) {
const TypeEntry* type = module_->types[i];
switch (type->kind()) {
case TypeEntryKind::Func: {
const FuncType* func_type = cast<FuncType>(type);
const FuncSignature* sig = &func_type->sig;
WriteHeader("func type", i);
WriteType(stream_, Type::Func);
Index num_params = sig->param_types.size();
Index num_results = sig->result_types.size();
WriteU32Leb128(stream_, num_params, "num params");
for (size_t j = 0; j < num_params; ++j) {
WriteType(stream_, sig->param_types[j]);
}
WriteU32Leb128(stream_, num_results, "num results");
for (size_t j = 0; j < num_results; ++j) {
WriteType(stream_, sig->result_types[j]);
}
break;
}
case TypeEntryKind::Struct: {
const StructType* struct_type = cast<StructType>(type);
WriteHeader("struct type", i);
WriteType(stream_, Type::Struct);
Index num_fields = struct_type->fields.size();
WriteU32Leb128(stream_, num_fields, "num fields");
for (size_t j = 0; j < num_fields; ++j) {
const Field& field = struct_type->fields[j];
WriteType(stream_, field.type);
stream_->WriteU8(field.mutable_, "field mutability");
}
break;
}
case TypeEntryKind::Array: {
const ArrayType* array_type = cast<ArrayType>(type);
WriteHeader("array type", i);
WriteType(stream_, Type::Array);
WriteType(stream_, array_type->field.type);
stream_->WriteU8(array_type->field.mutable_, "field mutability");
break;
}
}
}
EndSection();
}
if (module_->imports.size()) {
BeginKnownSection(BinarySection::Import);
WriteU32Leb128(stream_, module_->imports.size(), "num imports");
for (size_t i = 0; i < module_->imports.size(); ++i) {
const Import* import = module_->imports[i];
WriteHeader("import header", i);
WriteStr(stream_, import->module_name, "import module name",
PrintChars::Yes);
WriteStr(stream_, import->field_name, "import field name",
PrintChars::Yes);
stream_->WriteU8Enum(import->kind(), "import kind");
switch (import->kind()) {
case ExternalKind::Func:
WriteU32Leb128(
stream_,
module_->GetFuncTypeIndex(cast<FuncImport>(import)->func.decl),
"import signature index");
break;
case ExternalKind::Table:
WriteTable(&cast<TableImport>(import)->table);
break;
case ExternalKind::Memory:
WriteMemory(&cast<MemoryImport>(import)->memory);
break;
case ExternalKind::Global:
WriteGlobalHeader(&cast<GlobalImport>(import)->global);
break;
case ExternalKind::Tag:
WriteTagType(&cast<TagImport>(import)->tag);
break;
}
}
EndSection();
}
assert(module_->funcs.size() >= module_->num_func_imports);
Index num_funcs = module_->funcs.size() - module_->num_func_imports;
if (num_funcs) {
BeginKnownSection(BinarySection::Function);
WriteU32Leb128(stream_, num_funcs, "num functions");
for (size_t i = 0; i < num_funcs; ++i) {
const Func* func = module_->funcs[i + module_->num_func_imports];
char desc[100];
wabt_snprintf(desc, sizeof(desc), "function %" PRIzd " signature index",
i);
WriteU32Leb128(stream_, module_->GetFuncTypeIndex(func->decl), desc);
}
EndSection();
}
assert(module_->tables.size() >= module_->num_table_imports);
Index num_tables = module_->tables.size() - module_->num_table_imports;
if (num_tables) {
BeginKnownSection(BinarySection::Table);
WriteU32Leb128(stream_, num_tables, "num tables");
for (size_t i = 0; i < num_tables; ++i) {
const Table* table = module_->tables[i + module_->num_table_imports];
WriteHeader("table", i);
WriteTable(table);
}
EndSection();
}
assert(module_->memories.size() >= module_->num_memory_imports);
Index num_memories = module_->memories.size() - module_->num_memory_imports;
if (num_memories) {
BeginKnownSection(BinarySection::Memory);
WriteU32Leb128(stream_, num_memories, "num memories");
for (size_t i = 0; i < num_memories; ++i) {
const Memory* memory = module_->memories[i + module_->num_memory_imports];
WriteHeader("memory", i);
WriteMemory(memory);
}
EndSection();
}
assert(module_->tags.size() >= module_->num_tag_imports);
Index num_tags = module_->tags.size() - module_->num_tag_imports;
if (num_tags) {
BeginKnownSection(BinarySection::Tag);
WriteU32Leb128(stream_, num_tags, "tag count");
for (size_t i = 0; i < num_tags; ++i) {
WriteHeader("tag", i);
const Tag* tag = module_->tags[i + module_->num_tag_imports];
WriteTagType(tag);
}
EndSection();
}
assert(module_->globals.size() >= module_->num_global_imports);
Index num_globals = module_->globals.size() - module_->num_global_imports;
if (num_globals) {
BeginKnownSection(BinarySection::Global);
WriteU32Leb128(stream_, num_globals, "num globals");
for (size_t i = 0; i < num_globals; ++i) {
const Global* global = module_->globals[i + module_->num_global_imports];
WriteGlobalHeader(global);
WriteInitExpr(global->init_expr);
}
EndSection();
}
if (module_->exports.size()) {
BeginKnownSection(BinarySection::Export);
WriteU32Leb128(stream_, module_->exports.size(), "num exports");
for (const Export* export_ : module_->exports) {
WriteStr(stream_, export_->name, "export name", PrintChars::Yes);
stream_->WriteU8Enum(export_->kind, "export kind");
switch (export_->kind) {
case ExternalKind::Func: {
Index index = module_->GetFuncIndex(export_->var);
WriteU32Leb128(stream_, index, "export func index");
break;
}
case ExternalKind::Table: {
Index index = module_->GetTableIndex(export_->var);
WriteU32Leb128(stream_, index, "export table index");
break;
}
case ExternalKind::Memory: {
Index index = module_->GetMemoryIndex(export_->var);
WriteU32Leb128(stream_, index, "export memory index");
break;
}
case ExternalKind::Global: {
Index index = module_->GetGlobalIndex(export_->var);
WriteU32Leb128(stream_, index, "export global index");
break;
}
case ExternalKind::Tag: {
Index index = module_->GetTagIndex(export_->var);
WriteU32Leb128(stream_, index, "export tag index");
break;
}
}
}
EndSection();
}
if (module_->starts.size()) {
Index start_func_index = module_->GetFuncIndex(*module_->starts[0]);
if (start_func_index != kInvalidIndex) {
BeginKnownSection(BinarySection::Start);
WriteU32Leb128(stream_, start_func_index, "start func index");
EndSection();
}
}
if (module_->elem_segments.size()) {
BeginKnownSection(BinarySection::Elem);
WriteU32Leb128(stream_, module_->elem_segments.size(), "num elem segments");
for (size_t i = 0; i < module_->elem_segments.size(); ++i) {
ElemSegment* segment = module_->elem_segments[i];
WriteHeader("elem segment header", i);
// 1. flags
uint8_t flags = segment->GetFlags(module_);
stream_->WriteU8(flags, "segment flags");
// 2. optional target table
if (flags & SegExplicitIndex && segment->kind != SegmentKind::Declared) {
WriteU32Leb128(stream_, module_->GetTableIndex(segment->table_var),
"table index");
}
// 3. optional target location within the table (active segments only)
if (!(flags & SegPassive)) {
WriteInitExpr(segment->offset);
}
// 4. type of item in the following list (omitted for "legacy" segments)
if (flags & (SegPassive | SegExplicitIndex)) {
if (flags & SegUseElemExprs) {
WriteType(stream_, segment->elem_type, "elem expr list type");
} else {
stream_->WriteU8Enum(ExternalKind::Func, "elem list type");
}
}
// 5. actual list of elements (with extern indexes or elem expr's)
// preceeded by length
WriteU32Leb128(stream_, segment->elem_exprs.size(), "num elems");
if (flags & SegUseElemExprs) {
for (const ExprList& elem_expr : segment->elem_exprs) {
WriteInitExpr(elem_expr);
}
} else {
for (const ExprList& elem_expr : segment->elem_exprs) {
assert(elem_expr.size() == 1);
const Expr* expr = &elem_expr.front();
assert(expr->type() == ExprType::RefFunc);
WriteU32Leb128(stream_,
module_->GetFuncIndex(cast<RefFuncExpr>(expr)->var),
"elem function index");
}
}
}
EndSection();
}
if (options_.features.bulk_memory_enabled() &&
module_->data_segments.size()) {
// Keep track of the data count section offset so it can be removed if
// it isn't needed.
data_count_start_ = stream_->offset();
BeginKnownSection(BinarySection::DataCount);
WriteU32Leb128(stream_, module_->data_segments.size(), "data count");
EndSection();
data_count_end_ = stream_->offset();
}
if (num_funcs) {
code_start_ = stream_->offset();
BeginKnownSection(BinarySection::Code);
WriteU32Leb128(stream_, num_funcs, "num functions");
for (size_t i = 0; i < num_funcs; ++i) {
cur_func_index_ = i + module_->num_func_imports;
WriteHeader("function body", i);
const Func* func = module_->funcs[cur_func_index_];
/* TODO(binji): better guess of the size of the function body section */
const Offset leb_size_guess = 1;
Offset body_size_offset =
WriteU32Leb128Space(leb_size_guess, "func body size (guess)");
cur_func_start_offset_ = stream_->offset();
WriteFunc(func);
auto func_start_offset = body_size_offset - last_section_payload_offset_;
auto func_end_offset = stream_->offset() - last_section_payload_offset_;
auto delta = WriteFixupU32Leb128Size(body_size_offset, leb_size_guess,
"FIXUP func body size");
if (current_reloc_section_ && delta != 0) {
for (Reloc& reloc : current_reloc_section_->relocations) {
if (reloc.offset >= func_start_offset &&
reloc.offset <= func_end_offset) {
reloc.offset += delta;
}
}
}
}
EndSection();
}
// Remove the DataCount section if there are no instructions that require it.
if (options_.features.bulk_memory_enabled() &&
module_->data_segments.size() && !has_data_segment_instruction_) {
Offset size = stream_->offset() - data_count_end_;
if (size) {
// If the DataCount section was followed by anything, assert that it's
// only the Code section. This limits the amount of fixing-up that we
// need to do.
assert(data_count_end_ == code_start_);
assert(last_section_type_ == BinarySection::Code);
stream_->MoveData(data_count_start_, data_count_end_, size);
code_start_ = data_count_start_;
}
stream_->Truncate(data_count_start_ + size);
--section_count_;
// We just effectively decremented the code section's index; adjust anything
// that might have captured it.
for (RelocSection& section : reloc_sections_) {
if (section.section_index == section_count_) {
assert(last_section_type_ == BinarySection::Code);
--section.section_index;
}
}
}
WriteCodeMetadataSections();
if (module_->data_segments.size()) {
BeginKnownSection(BinarySection::Data);
WriteU32Leb128(stream_, module_->data_segments.size(), "num data segments");
for (size_t i = 0; i < module_->data_segments.size(); ++i) {
const DataSegment* segment = module_->data_segments[i];
WriteHeader("data segment header", i);
uint8_t flags = segment->GetFlags(module_);
stream_->WriteU8(flags, "segment flags");
if (!(flags & SegPassive)) {
if (options_.features.multi_memory_enabled() &&
(flags & SegExplicitIndex)) {
WriteU32Leb128(stream_, module_->GetMemoryIndex(segment->memory_var),
"memidx");
} else {
assert(module_->GetMemoryIndex(segment->memory_var) == 0);
}
WriteInitExpr(segment->offset);
}
WriteU32Leb128(stream_, segment->data.size(), "data segment size");
WriteHeader("data segment data", i);
stream_->WriteData(segment->data, "data segment data");
}
EndSection();
}
if (options_.write_debug_names) {
std::vector<std::string> index_to_name;
char desc[100];
BeginCustomSection(WABT_BINARY_SECTION_NAME);
if (!module_->name.empty()) {
WriteU32Leb128(stream_, NameSectionSubsection::Module,
"module name type");
BeginSubsection("module name subsection");
WriteDebugName(stream_, module_->name, "module name");
EndSubsection();
}
WriteNames<Func>(module_->funcs, NameSectionSubsection::Function);
WriteU32Leb128(stream_, 2, "local name type");
BeginSubsection("local name subsection");
WriteU32Leb128(stream_, module_->funcs.size(), "num functions");
for (size_t i = 0; i < module_->funcs.size(); ++i) {
const Func* func = module_->funcs[i];
Index num_params_and_locals = func->GetNumParamsAndLocals();
MakeTypeBindingReverseMapping(num_params_and_locals, func->bindings,
&index_to_name);
Index num_named = 0;
for (auto s : index_to_name) {
if (!s.empty()) {
num_named++;
}
}
WriteU32Leb128(stream_, i, "function index");
WriteU32Leb128(stream_, num_named, "num locals");
for (size_t j = 0; j < num_params_and_locals; ++j) {
const std::string& name = index_to_name[j];
if (!name.empty()) {
wabt_snprintf(desc, sizeof(desc), "local name %" PRIzd, j);
WriteU32Leb128(stream_, j, "local index");
WriteDebugName(stream_, name, desc);
}
}
}
EndSubsection();
WriteNames<TypeEntry>(module_->types, NameSectionSubsection::Type);
WriteNames<Table>(module_->tables, NameSectionSubsection::Table);
WriteNames<Memory>(module_->memories, NameSectionSubsection::Memory);
WriteNames<Global>(module_->globals, NameSectionSubsection::Global);
WriteNames<ElemSegment>(module_->elem_segments,
NameSectionSubsection::ElemSegment);
WriteNames<DataSegment>(module_->data_segments,
NameSectionSubsection::DataSegment);
WriteNames<Tag>(module_->tags, NameSectionSubsection::Tag);
EndSection();
}
if (options_.relocatable) {
WriteLinkingSection();
for (RelocSection& section : reloc_sections_) {
WriteRelocSection(§ion);
}
}
return stream_->result();
}
void BinaryWriter::WriteCodeMetadataSections() {
if (code_metadata_sections_.empty())
return;
section_count_ -= 1;
// We have to increment the code section's index; adjust anything
// that might have captured it.
for (RelocSection& section : reloc_sections_) {
if (section.section_index == section_count_) {
assert(last_section_type_ == BinarySection::Code);
section.section_index += code_metadata_sections_.size();
}
}
MemoryStream tmp_stream;
Stream* main_stream = stream_;
stream_ = &tmp_stream;
for (auto& s : code_metadata_sections_) {
std::string name = "metadata.code.";
name.append(s.first);
auto& section = s.second;
BeginCustomSection(name.c_str());
WriteU32Leb128(stream_, section.entries.size(), "function count");
for (auto& f : section.entries) {
WriteU32Leb128WithReloc(f.func_idx, "function index",
RelocType::FuncIndexLEB);
WriteU32Leb128(stream_, f.entries.size(), "instances count");
for (auto& a : f.entries) {
WriteU32Leb128(stream_, a.offset, "code offset");
WriteU32Leb128(stream_, a.data.size(), "data length");
stream_->WriteData(a.data.data(), a.data.size(), "data",
PrintChars::Yes);
}
}
EndSection();
}
stream_ = main_stream;
auto buf = tmp_stream.ReleaseOutputBuffer();
stream_->MoveData(code_start_ + buf->data.size(), code_start_,
stream_->offset() - code_start_);
stream_->WriteDataAt(code_start_, buf->data.data(), buf->data.size());
stream_->AddOffset(buf->data.size());
code_start_ += buf->data.size();
section_count_ += 1;
last_section_type_ = BinarySection::Code;
}
} // end anonymous namespace
Result WriteBinaryModule(Stream* stream,
const Module* module,
const WriteBinaryOptions& options) {
BinaryWriter binary_writer(stream, options, module);
return binary_writer.WriteModule();
}
} // namespace wabt