use crate::codegen::*;
use crate::{
backend::{Backend, CompilerConfig, RunnableModule},
error::CompileError,
module::{
DataInitializer, ExportIndex, ImportName, ModuleInfo, StringTable, StringTableBuilder,
TableInitializer,
},
structures::{Map, TypedIndex},
types::{
ElementType, FuncIndex, FuncSig, GlobalDescriptor, GlobalIndex, GlobalInit,
ImportedGlobalIndex, Initializer, MemoryDescriptor, MemoryIndex, SigIndex, TableDescriptor,
TableIndex, Type, Value,
},
units::Pages,
};
use std::collections::HashMap;
use std::fmt::Debug;
use std::sync::{Arc, RwLock};
use wasmparser::{
BinaryReaderError, ExternalKind, FuncType, ImportSectionEntryType, Operator, Type as WpType,
WasmDecoder,
};
#[derive(Debug)]
pub enum LoadError {
Parse(BinaryReaderError),
Codegen(String),
}
impl From<LoadError> for CompileError {
fn from(other: LoadError) -> CompileError {
CompileError::InternalError {
msg: format!("{:?}", other),
}
}
}
impl From<BinaryReaderError> for LoadError {
fn from(other: BinaryReaderError) -> LoadError {
LoadError::Parse(other)
}
}
pub fn read_module<
MCG: ModuleCodeGenerator<FCG, RM, E>,
FCG: FunctionCodeGenerator<E>,
RM: RunnableModule,
E: Debug,
>(
wasm: &[u8],
backend: Backend,
mcg: &mut MCG,
middlewares: &mut MiddlewareChain,
compiler_config: &CompilerConfig,
) -> Result<Arc<RwLock<ModuleInfo>>, LoadError> {
mcg.feed_compiler_config(compiler_config)
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
let info = Arc::new(RwLock::new(ModuleInfo {
memories: Map::new(),
globals: Map::new(),
tables: Map::new(),
imported_functions: Map::new(),
imported_memories: Map::new(),
imported_tables: Map::new(),
imported_globals: Map::new(),
exports: Default::default(),
data_initializers: Vec::new(),
elem_initializers: Vec::new(),
start_func: None,
func_assoc: Map::new(),
signatures: Map::new(),
backend: backend,
namespace_table: StringTable::new(),
name_table: StringTable::new(),
em_symbol_map: compiler_config.symbol_map.clone(),
custom_sections: HashMap::new(),
}));
let mut parser = wasmparser::ValidatingParser::new(
wasm,
Some(validating_parser_config(&compiler_config.features)),
);
let mut namespace_builder = Some(StringTableBuilder::new());
let mut name_builder = Some(StringTableBuilder::new());
let mut func_count: usize = 0;
let mut mcg_info_fed = false;
loop {
use wasmparser::ParserState;
let state = parser.read();
match *state {
ParserState::Error(err) => Err(LoadError::Parse(err))?,
ParserState::TypeSectionEntry(ref ty) => {
info.write()
.unwrap()
.signatures
.push(func_type_to_func_sig(ty)?);
}
ParserState::ImportSectionEntry { module, field, ty } => {
let namespace_index = namespace_builder.as_mut().unwrap().register(module);
let name_index = name_builder.as_mut().unwrap().register(field);
let import_name = ImportName {
namespace_index,
name_index,
};
match ty {
ImportSectionEntryType::Function(sigindex) => {
let sigindex = SigIndex::new(sigindex as usize);
info.write().unwrap().imported_functions.push(import_name);
info.write().unwrap().func_assoc.push(sigindex);
mcg.feed_import_function()
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
}
ImportSectionEntryType::Table(table_ty) => {
assert_eq!(table_ty.element_type, WpType::AnyFunc);
let table_desc = TableDescriptor {
element: ElementType::Anyfunc,
minimum: table_ty.limits.initial,
maximum: table_ty.limits.maximum,
};
info.write()
.unwrap()
.imported_tables
.push((import_name, table_desc));
}
ImportSectionEntryType::Memory(memory_ty) => {
let mem_desc = MemoryDescriptor {
minimum: Pages(memory_ty.limits.initial),
maximum: memory_ty.limits.maximum.map(|max| Pages(max)),
shared: memory_ty.shared,
};
info.write()
.unwrap()
.imported_memories
.push((import_name, mem_desc));
}
ImportSectionEntryType::Global(global_ty) => {
let global_desc = GlobalDescriptor {
mutable: global_ty.mutable,
ty: wp_type_to_type(global_ty.content_type)?,
};
info.write()
.unwrap()
.imported_globals
.push((import_name, global_desc));
}
}
}
ParserState::FunctionSectionEntry(sigindex) => {
let sigindex = SigIndex::new(sigindex as usize);
info.write().unwrap().func_assoc.push(sigindex);
}
ParserState::TableSectionEntry(table_ty) => {
let table_desc = TableDescriptor {
element: ElementType::Anyfunc,
minimum: table_ty.limits.initial,
maximum: table_ty.limits.maximum,
};
info.write().unwrap().tables.push(table_desc);
}
ParserState::MemorySectionEntry(memory_ty) => {
let mem_desc = MemoryDescriptor {
minimum: Pages(memory_ty.limits.initial),
maximum: memory_ty.limits.maximum.map(|max| Pages(max)),
shared: memory_ty.shared,
};
info.write().unwrap().memories.push(mem_desc);
}
ParserState::ExportSectionEntry { field, kind, index } => {
let export_index = match kind {
ExternalKind::Function => ExportIndex::Func(FuncIndex::new(index as usize)),
ExternalKind::Table => ExportIndex::Table(TableIndex::new(index as usize)),
ExternalKind::Memory => ExportIndex::Memory(MemoryIndex::new(index as usize)),
ExternalKind::Global => ExportIndex::Global(GlobalIndex::new(index as usize)),
};
info.write()
.unwrap()
.exports
.insert(field.to_string(), export_index);
}
ParserState::StartSectionEntry(start_index) => {
info.write().unwrap().start_func = Some(FuncIndex::new(start_index as usize));
}
ParserState::BeginFunctionBody { .. } => {
let id = func_count;
if !mcg_info_fed {
mcg_info_fed = true;
info.write().unwrap().namespace_table =
namespace_builder.take().unwrap().finish();
info.write().unwrap().name_table = name_builder.take().unwrap().finish();
mcg.feed_signatures(info.read().unwrap().signatures.clone())
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
mcg.feed_function_signatures(info.read().unwrap().func_assoc.clone())
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
mcg.check_precondition(&info.read().unwrap())
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
}
let fcg = mcg
.next_function(Arc::clone(&info))
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
let info_read = info.read().unwrap();
let sig = info_read
.signatures
.get(
*info
.read()
.unwrap()
.func_assoc
.get(FuncIndex::new(
id as usize + info.read().unwrap().imported_functions.len(),
))
.unwrap(),
)
.unwrap();
for ret in sig.returns() {
fcg.feed_return(type_to_wp_type(*ret))
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
}
for param in sig.params() {
fcg.feed_param(type_to_wp_type(*param))
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
}
let mut body_begun = false;
loop {
let state = parser.read();
match state {
ParserState::Error(err) => return Err(LoadError::Parse(*err)),
ParserState::FunctionBodyLocals { ref locals } => {
for &(count, ty) in locals.iter() {
fcg.feed_local(ty, count as usize)
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
}
}
ParserState::CodeOperator(op) => {
if !body_begun {
body_begun = true;
fcg.begin_body(&info.read().unwrap())
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
middlewares
.run(
Some(fcg),
Event::Internal(InternalEvent::FunctionBegin(id as u32)),
&info.read().unwrap(),
)
.map_err(|x| LoadError::Codegen(x))?;
}
middlewares
.run(Some(fcg), Event::Wasm(op), &info.read().unwrap())
.map_err(|x| LoadError::Codegen(x))?;
}
ParserState::EndFunctionBody => break,
_ => unreachable!(),
}
}
middlewares
.run(
Some(fcg),
Event::Internal(InternalEvent::FunctionEnd),
&info.read().unwrap(),
)
.map_err(|x| LoadError::Codegen(x))?;
fcg.finalize()
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
func_count = func_count.wrapping_add(1);
}
ParserState::BeginActiveElementSectionEntry(table_index) => {
let table_index = TableIndex::new(table_index as usize);
let mut elements: Option<Vec<FuncIndex>> = None;
let mut base: Option<Initializer> = None;
loop {
let state = parser.read();
match *state {
ParserState::Error(err) => return Err(LoadError::Parse(err)),
ParserState::InitExpressionOperator(ref op) => {
base = Some(eval_init_expr(op)?)
}
ParserState::ElementSectionEntryBody(ref _elements) => {
elements = Some(
_elements
.iter()
.cloned()
.map(|index| FuncIndex::new(index as usize))
.collect(),
);
}
ParserState::BeginInitExpressionBody
| ParserState::EndInitExpressionBody => {}
ParserState::EndElementSectionEntry => break,
_ => unreachable!(),
}
}
let table_init = TableInitializer {
table_index,
base: base.unwrap(),
elements: elements.unwrap(),
};
info.write().unwrap().elem_initializers.push(table_init);
}
ParserState::BeginActiveDataSectionEntry(memory_index) => {
let memory_index = MemoryIndex::new(memory_index as usize);
let mut base: Option<Initializer> = None;
let mut data: Vec<u8> = vec![];
loop {
let state = parser.read();
match *state {
ParserState::Error(err) => return Err(LoadError::Parse(err)),
ParserState::InitExpressionOperator(ref op) => {
base = Some(eval_init_expr(op)?)
}
ParserState::DataSectionEntryBodyChunk(chunk) => {
data.extend_from_slice(chunk);
}
ParserState::BeginInitExpressionBody
| ParserState::EndInitExpressionBody => {}
ParserState::BeginDataSectionEntryBody(_)
| ParserState::EndDataSectionEntryBody => {}
ParserState::EndDataSectionEntry => break,
_ => unreachable!(),
}
}
let data_init = DataInitializer {
memory_index,
base: base.unwrap(),
data,
};
info.write().unwrap().data_initializers.push(data_init);
}
ParserState::BeginGlobalSectionEntry(ty) => {
let init = loop {
let state = parser.read();
match *state {
ParserState::Error(err) => return Err(LoadError::Parse(err)),
ParserState::InitExpressionOperator(ref op) => {
break eval_init_expr(op)?;
}
ParserState::BeginInitExpressionBody => {}
_ => unreachable!(),
}
};
let desc = GlobalDescriptor {
mutable: ty.mutable,
ty: wp_type_to_type(ty.content_type)?,
};
let global_init = GlobalInit { desc, init };
info.write().unwrap().globals.push(global_init);
}
ParserState::EndWasm => {
if !mcg_info_fed {
info.write().unwrap().namespace_table =
namespace_builder.take().unwrap().finish();
info.write().unwrap().name_table = name_builder.take().unwrap().finish();
mcg.feed_signatures(info.read().unwrap().signatures.clone())
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
mcg.feed_function_signatures(info.read().unwrap().func_assoc.clone())
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
mcg.check_precondition(&info.read().unwrap())
.map_err(|x| LoadError::Codegen(format!("{:?}", x)))?;
}
break;
}
_ => {}
}
}
Ok(info)
}
pub fn wp_type_to_type(ty: WpType) -> Result<Type, BinaryReaderError> {
Ok(match ty {
WpType::I32 => Type::I32,
WpType::I64 => Type::I64,
WpType::F32 => Type::F32,
WpType::F64 => Type::F64,
WpType::V128 => Type::V128,
_ => panic!("broken invariant, invalid type"),
})
}
pub fn type_to_wp_type(ty: Type) -> WpType {
match ty {
Type::I32 => WpType::I32,
Type::I64 => WpType::I64,
Type::F32 => WpType::F32,
Type::F64 => WpType::F64,
Type::V128 => WpType::V128,
}
}
fn func_type_to_func_sig(func_ty: &FuncType) -> Result<FuncSig, BinaryReaderError> {
assert_eq!(func_ty.form, WpType::Func);
Ok(FuncSig::new(
func_ty
.params
.iter()
.cloned()
.map(wp_type_to_type)
.collect::<Result<Vec<_>, _>>()?,
func_ty
.returns
.iter()
.cloned()
.map(wp_type_to_type)
.collect::<Result<Vec<_>, _>>()?,
))
}
fn eval_init_expr(op: &Operator) -> Result<Initializer, BinaryReaderError> {
Ok(match *op {
Operator::GetGlobal { global_index } => {
Initializer::GetGlobal(ImportedGlobalIndex::new(global_index as usize))
}
Operator::I32Const { value } => Initializer::Const(Value::I32(value)),
Operator::I64Const { value } => Initializer::Const(Value::I64(value)),
Operator::F32Const { value } => {
Initializer::Const(Value::F32(f32::from_bits(value.bits())))
}
Operator::F64Const { value } => {
Initializer::Const(Value::F64(f64::from_bits(value.bits())))
}
Operator::V128Const { value } => {
Initializer::Const(Value::V128(u128::from_le_bytes(*value.bytes())))
}
_ => {
return Err(BinaryReaderError {
message: "init expr evaluation failed: unsupported opcode",
offset: -1isize as usize,
});
}
})
}