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//! Generation of Wasm
// FIXME(#1000): component support in `wasm-smith` is a work in progress.
#![allow(unused_variables, dead_code)]
use crate::{arbitrary_loop, Config};
use arbitrary::{Arbitrary, Result, Unstructured};
use std::collections::BTreeMap;
use std::{
collections::{HashMap, HashSet},
rc::Rc,
};
use wasm_encoder::{
ComponentTypeRef, ComponentValType, HeapType, PrimitiveValType, RefType, TypeBounds, ValType,
};
mod encode;
/// A pseudo-random WebAssembly [component].
///
/// Construct instances of this type with [the `Arbitrary`
///
/// [component]: https://github.com/WebAssembly/component-model/blob/ast-and-binary/design/MVP/Explainer.md
///
/// ## Configured Generated Components
///
/// The `Arbitrary` implementation uses the [`Config::default()`][crate::Config]
/// configuration. If you want to customize the shape of generated components,
/// create your own [`Config`][crate::Config] instance and pass it to
/// [`Component::new`][crate::Component::new].
#[derive(Debug)]
pub struct Component {
sections: Vec<Section>,
}
/// A builder to create a component (and possibly a whole tree of nested
/// components).
///
/// Maintains a stack of components we are currently building, as well as
/// metadata about them. The split between `Component` and `ComponentBuilder` is
/// that the builder contains metadata that is purely used when generating
/// components and is unnecessary after we are done generating the structure of
/// the components and only need to encode an already-generated component to
/// bytes.
#[derive(Debug)]
struct ComponentBuilder {
config: Config,
// The set of core `valtype`s that we are configured to generate.
core_valtypes: Vec<ValType>,
// Stack of types scopes that are currently available.
//
// There is an entry in this stack for each component, but there can also be
// additional entries for module/component/instance types, each of which
// have their own scope.
//
// This stack is always non-empty and the last entry is always the current
// scope.
//
// When a particular scope can alias outer types, it can alias from any
// scope that is older than it (i.e. `types_scope[i]` can alias from
// `types_scope[j]` when `j <= i`).
types: Vec<TypesScope>,
// The set of components we are currently building and their associated
// metadata.
components: Vec<ComponentContext>,
// Whether we are in the final bits of generating this component and we just
// need to ensure that the minimum number of entities configured have all
// been generated. This changes the behavior of various
// `arbitrary_<section>` methods to always fill in their minimums.
fill_minimums: bool,
// Our maximums for these entities are applied across the whole component
// tree, not per-component.
total_components: usize,
total_modules: usize,
total_instances: usize,
total_values: usize,
}
#[derive(Debug, Clone)]
enum ComponentOrCoreFuncType {
Component(Rc<FuncType>),
Core(Rc<crate::core::FuncType>),
}
impl ComponentOrCoreFuncType {
fn as_core(&self) -> &Rc<crate::core::FuncType> {
match self {
ComponentOrCoreFuncType::Core(t) => t,
ComponentOrCoreFuncType::Component(_) => panic!("not a core func type"),
}
}
fn as_component(&self) -> &Rc<FuncType> {
match self {
ComponentOrCoreFuncType::Core(_) => panic!("not a component func type"),
ComponentOrCoreFuncType::Component(t) => t,
}
}
}
#[derive(Debug, Clone)]
enum ComponentOrCoreInstanceType {
Component(Rc<InstanceType>),
Core(BTreeMap<String, crate::core::EntityType>),
}
/// Metadata (e.g. contents of various index spaces) we keep track of on a
/// per-component basis.
#[derive(Debug)]
struct ComponentContext {
// The actual component itself.
component: Component,
// The number of imports we have generated thus far.
num_imports: usize,
// The set of names of imports we've generated thus far.
import_names: HashSet<String>,
// The set of URLs of imports we've generated thus far.
import_urls: HashSet<String>,
// This component's function index space.
funcs: Vec<ComponentOrCoreFuncType>,
// Which entries in `funcs` are component functions?
component_funcs: Vec<u32>,
// Which entries in `component_funcs` are component functions that only use scalar
// types?
scalar_component_funcs: Vec<u32>,
// Which entries in `funcs` are core Wasm functions?
//
// Note that a component can't import core functions, so these entries will
// never point to a `Section::Import`.
core_funcs: Vec<u32>,
// This component's component index space.
//
// An indirect list of all directly-nested (not transitive) components
// inside this component.
//
// Each entry is of the form `(i, j)` where `component.sections[i]` is
// guaranteed to be either
//
// * a `Section::Component` and we are referencing the component defined in
// that section (in this case `j` must also be `0`, since a component
// section can only contain a single nested component), or
//
// * a `Section::Import` and we are referencing the `j`th import in that
// section, which is guaranteed to be a component import.
components: Vec<(usize, usize)>,
// This component's module index space.
//
// An indirect list of all directly-nested (not transitive) modules
// inside this component.
//
// Each entry is of the form `(i, j)` where `component.sections[i]` is
// guaranteed to be either
//
// * a `Section::Core` and we are referencing the module defined in that
// section (in this case `j` must also be `0`, since a core section can
// only contain a single nested module), or
//
// * a `Section::Import` and we are referencing the `j`th import in that
// section, which is guaranteed to be a module import.
modules: Vec<(usize, usize)>,
// This component's instance index space.
instances: Vec<ComponentOrCoreInstanceType>,
// This component's value index space.
values: Vec<ComponentValType>,
}
impl ComponentContext {
fn empty() -> Self {
ComponentContext {
component: Component::empty(),
num_imports: 0,
import_names: HashSet::default(),
import_urls: HashSet::default(),
funcs: vec![],
component_funcs: vec![],
scalar_component_funcs: vec![],
core_funcs: vec![],
components: vec![],
modules: vec![],
instances: vec![],
values: vec![],
}
}
fn num_modules(&self) -> usize {
self.modules.len()
}
fn num_components(&self) -> usize {
self.components.len()
}
fn num_instances(&self) -> usize {
self.instances.len()
}
fn num_funcs(&self) -> usize {
self.funcs.len()
}
fn num_values(&self) -> usize {
self.values.len()
}
}
#[derive(Debug, Default)]
struct TypesScope {
// All core types in this scope, regardless of kind.
core_types: Vec<Rc<CoreType>>,
// The indices of all the entries in `core_types` that are core function types.
core_func_types: Vec<u32>,
// The indices of all the entries in `core_types` that are module types.
module_types: Vec<u32>,
// All component types in this index space, regardless of kind.
types: Vec<Rc<Type>>,
// The indices of all the entries in `types` that are defined value types.
defined_types: Vec<u32>,
// The indices of all the entries in `types` that are func types.
func_types: Vec<u32>,
// A map from function types to their indices in the types space.
func_type_to_indices: HashMap<Rc<FuncType>, Vec<u32>>,
// The indices of all the entries in `types` that are component types.
component_types: Vec<u32>,
// The indices of all the entries in `types` that are instance types.
instance_types: Vec<u32>,
}
impl TypesScope {
fn push(&mut self, ty: Rc<Type>) -> u32 {
let ty_idx = u32::try_from(self.types.len()).unwrap();
let kind_list = match &*ty {
Type::Defined(_) => &mut self.defined_types,
Type::Func(func_ty) => {
self.func_type_to_indices
.entry(func_ty.clone())
.or_default()
.push(ty_idx);
&mut self.func_types
}
Type::Component(_) => &mut self.component_types,
Type::Instance(_) => &mut self.instance_types,
};
kind_list.push(ty_idx);
self.types.push(ty);
ty_idx
}
fn push_core(&mut self, ty: Rc<CoreType>) -> u32 {
let ty_idx = u32::try_from(self.core_types.len()).unwrap();
let kind_list = match &*ty {
CoreType::Func(_) => &mut self.core_func_types,
CoreType::Module(_) => &mut self.module_types,
};
kind_list.push(ty_idx);
self.core_types.push(ty);
ty_idx
}
fn get(&self, index: u32) -> &Rc<Type> {
&self.types[index as usize]
}
fn get_core(&self, index: u32) -> &Rc<CoreType> {
&self.core_types[index as usize]
}
fn get_func(&self, index: u32) -> &Rc<FuncType> {
match &**self.get(index) {
Type::Func(f) => f,
_ => panic!("get_func on non-function type"),
}
}
fn can_ref_type(&self) -> bool {
// All component types and core module types may be referenced
!self.types.is_empty() || !self.module_types.is_empty()
}
}
impl<'a> Arbitrary<'a> for Component {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
Component::new(Config::default(), u)
}
}
#[derive(Default)]
struct EntityCounts {
globals: usize,
tables: usize,
memories: usize,
tags: usize,
funcs: usize,
}
impl Component {
/// Construct a new `Component` using the given configuration.
pub fn new(config: Config, u: &mut Unstructured) -> Result<Self> {
let mut builder = ComponentBuilder::new(config);
builder.build(u)
}
fn empty() -> Self {
Component { sections: vec![] }
}
}
#[must_use]
enum Step {
Finished(Component),
StillBuilding,
}
impl Step {
fn unwrap_still_building(self) {
match self {
Step::Finished(_) => panic!(
"`Step::unwrap_still_building` called on a `Step` that is not `StillBuilding`"
),
Step::StillBuilding => {}
}
}
}
impl ComponentBuilder {
fn new(config: Config) -> Self {
ComponentBuilder {
config,
core_valtypes: vec![],
types: vec![Default::default()],
components: vec![ComponentContext::empty()],
fill_minimums: false,
total_components: 0,
total_modules: 0,
total_instances: 0,
total_values: 0,
}
}
fn build(&mut self, u: &mut Unstructured) -> Result<Component> {
self.core_valtypes = crate::core::configured_valtypes(&self.config);
let mut choices: Vec<fn(&mut ComponentBuilder, &mut Unstructured) -> Result<Step>> = vec![];
loop {
choices.clear();
choices.push(Self::finish_component);
// Only add any choice other than "finish what we've generated thus
// far" when there is more arbitrary fuzzer data for us to consume.
if !u.is_empty() {
choices.push(Self::arbitrary_custom_section);
// NB: we add each section as a choice even if we've already
// generated our maximum number of entities in that section so that
// we can exercise adding empty sections to the end of the module.
choices.push(Self::arbitrary_core_type_section);
choices.push(Self::arbitrary_type_section);
choices.push(Self::arbitrary_import_section);
choices.push(Self::arbitrary_canonical_section);
if self.total_modules < self.config.max_modules {
choices.push(Self::arbitrary_core_module_section);
}
if self.components.len() < self.config.max_nesting_depth
&& self.total_components < self.config.max_components
{
choices.push(Self::arbitrary_component_section);
}
// FIXME(#1000)
//
// choices.push(Self::arbitrary_instance_section);
// choices.push(Self::arbitrary_export_section);
// choices.push(Self::arbitrary_start_section);
// choices.push(Self::arbitrary_alias_section);
}
let f = u.choose(&choices)?;
match f(self, u)? {
Step::StillBuilding => {}
Step::Finished(component) => {
if self.components.is_empty() {
// If we just finished the root component, then return it.
return Ok(component);
} else {
// Otherwise, add it as a nested component in the parent.
self.push_section(Section::Component(component));
}
}
}
}
}
fn finish_component(&mut self, u: &mut Unstructured) -> Result<Step> {
// Ensure we've generated all of our minimums.
self.fill_minimums = true;
{
if self.current_type_scope().types.len() < self.config.min_types {
self.arbitrary_type_section(u)?.unwrap_still_building();
}
if self.component().num_imports < self.config.min_imports {
self.arbitrary_import_section(u)?.unwrap_still_building();
}
if self.component().funcs.len() < self.config.min_funcs {
self.arbitrary_canonical_section(u)?.unwrap_still_building();
}
}
self.fill_minimums = false;
self.types
.pop()
.expect("should have a types scope for the component we are finishing");
Ok(Step::Finished(self.components.pop().unwrap().component))
}
fn component(&self) -> &ComponentContext {
self.components.last().unwrap()
}
fn component_mut(&mut self) -> &mut ComponentContext {
self.components.last_mut().unwrap()
}
fn last_section(&self) -> Option<&Section> {
self.component().component.sections.last()
}
fn last_section_mut(&mut self) -> Option<&mut Section> {
self.component_mut().component.sections.last_mut()
}
fn push_section(&mut self, section: Section) {
self.component_mut().component.sections.push(section);
}
fn ensure_section(
&mut self,
mut predicate: impl FnMut(&Section) -> bool,
mut make_section: impl FnMut() -> Section,
) -> &mut Section {
match self.last_section() {
Some(sec) if predicate(sec) => {}
_ => self.push_section(make_section()),
}
self.last_section_mut().unwrap()
}
fn arbitrary_custom_section(&mut self, u: &mut Unstructured) -> Result<Step> {
self.push_section(Section::Custom(u.arbitrary()?));
Ok(Step::StillBuilding)
}
fn push_type(&mut self, ty: Rc<Type>) -> u32 {
match self.ensure_section(
|s| matches!(s, Section::Type(_)),
|| Section::Type(TypeSection { types: vec![] }),
) {
Section::Type(TypeSection { types }) => {
types.push(ty.clone());
self.current_type_scope_mut().push(ty)
}
_ => unreachable!(),
}
}
fn push_core_type(&mut self, ty: Rc<CoreType>) -> u32 {
match self.ensure_section(
|s| matches!(s, Section::CoreType(_)),
|| Section::CoreType(CoreTypeSection { types: vec![] }),
) {
Section::CoreType(CoreTypeSection { types }) => {
types.push(ty.clone());
self.current_type_scope_mut().push_core(ty)
}
_ => unreachable!(),
}
}
fn arbitrary_core_type_section(&mut self, u: &mut Unstructured) -> Result<Step> {
self.push_section(Section::CoreType(CoreTypeSection { types: vec![] }));
let min = if self.fill_minimums {
self.config
.min_types
.saturating_sub(self.current_type_scope().types.len())
} else {
0
};
let max = self.config.max_types - self.current_type_scope().types.len();
arbitrary_loop(u, min, max, |u| {
let mut type_fuel = self.config.max_type_size;
let ty = self.arbitrary_core_type(u, &mut type_fuel)?;
self.push_core_type(ty);
Ok(true)
})?;
Ok(Step::StillBuilding)
}
fn arbitrary_core_type(
&self,
u: &mut Unstructured,
type_fuel: &mut u32,
) -> Result<Rc<CoreType>> {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(Rc::new(CoreType::Module(Rc::new(ModuleType::default()))));
}
let ty = match u.int_in_range::<u8>(0..=1)? {
0 => CoreType::Func(arbitrary_func_type(
u,
&self.config,
&self.core_valtypes,
if self.config.multi_value_enabled {
None
} else {
Some(1)
},
0,
)?),
1 => CoreType::Module(self.arbitrary_module_type(u, type_fuel)?),
_ => unreachable!(),
};
Ok(Rc::new(ty))
}
fn arbitrary_type_section(&mut self, u: &mut Unstructured) -> Result<Step> {
self.push_section(Section::Type(TypeSection { types: vec![] }));
let min = if self.fill_minimums {
self.config
.min_types
.saturating_sub(self.current_type_scope().types.len())
} else {
0
};
let max = self.config.max_types - self.current_type_scope().types.len();
arbitrary_loop(u, min, max, |u| {
let mut type_fuel = self.config.max_type_size;
let ty = self.arbitrary_type(u, &mut type_fuel)?;
self.push_type(ty);
Ok(true)
})?;
Ok(Step::StillBuilding)
}
fn arbitrary_type_ref<'a>(
&self,
u: &mut Unstructured<'a>,
for_import: bool,
for_type_def: bool,
) -> Result<Option<ComponentTypeRef>> {
let mut choices: Vec<fn(&Self, &mut Unstructured) -> Result<ComponentTypeRef>> = Vec::new();
let scope = self.current_type_scope();
if !scope.module_types.is_empty()
&& (for_type_def || !for_import || self.total_modules < self.config.max_modules)
{
choices.push(|me, u| {
Ok(ComponentTypeRef::Module(
*u.choose(&me.current_type_scope().module_types)?,
))
});
}
// Types cannot be imported currently
if !for_import
&& !scope.types.is_empty()
&& (for_type_def || scope.types.len() < self.config.max_types)
{
choices.push(|me, u| {
Ok(ComponentTypeRef::Type(TypeBounds::Eq(u.int_in_range(
0..=u32::try_from(me.current_type_scope().types.len() - 1).unwrap(),
)?)))
});
}
// TODO: wasm-smith needs to ensure that every arbitrary value gets used exactly once.
// until that time, don't import values
// if for_type_def || !for_import || self.total_values < self.config.max_values() {
// choices.push(|me, u| Ok(ComponentTypeRef::Value(me.arbitrary_component_val_type(u)?)));
// }
if !scope.func_types.is_empty()
&& (for_type_def || !for_import || self.component().num_funcs() < self.config.max_funcs)
{
choices.push(|me, u| {
Ok(ComponentTypeRef::Func(
*u.choose(&me.current_type_scope().func_types)?,
))
});
}
if !scope.component_types.is_empty()
&& (for_type_def || !for_import || self.total_components < self.config.max_components)
{
choices.push(|me, u| {
Ok(ComponentTypeRef::Component(
*u.choose(&me.current_type_scope().component_types)?,
))
});
}
if !scope.instance_types.is_empty()
&& (for_type_def || !for_import || self.total_instances < self.config.max_instances)
{
choices.push(|me, u| {
Ok(ComponentTypeRef::Instance(
*u.choose(&me.current_type_scope().instance_types)?,
))
});
}
if choices.is_empty() {
return Ok(None);
}
let f = u.choose(&choices)?;
f(self, u).map(Option::Some)
}
fn arbitrary_type(&mut self, u: &mut Unstructured, type_fuel: &mut u32) -> Result<Rc<Type>> {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(Rc::new(Type::Defined(
self.arbitrary_defined_type(u, type_fuel)?,
)));
}
let ty = match u.int_in_range::<u8>(0..=3)? {
0 => Type::Defined(self.arbitrary_defined_type(u, type_fuel)?),
1 => Type::Func(self.arbitrary_func_type(u, type_fuel)?),
2 => Type::Component(self.arbitrary_component_type(u, type_fuel)?),
3 => Type::Instance(self.arbitrary_instance_type(u, type_fuel)?),
_ => unreachable!(),
};
Ok(Rc::new(ty))
}
fn arbitrary_module_type(
&self,
u: &mut Unstructured,
type_fuel: &mut u32,
) -> Result<Rc<ModuleType>> {
let mut defs = vec![];
let mut has_memory = false;
let mut has_canonical_abi_realloc = false;
let mut has_canonical_abi_free = false;
let mut types: Vec<Rc<crate::core::FuncType>> = vec![];
let mut imports = HashMap::new();
let mut exports = HashSet::new();
let mut counts = EntityCounts::default();
// Special case the canonical ABI functions since certain types can only
// be passed across the component boundary if they exist and
// randomly generating them is extremely unlikely.
// `memory`
if counts.memories < self.config.max_memories && u.ratio::<u8>(99, 100)? {
defs.push(ModuleTypeDef::Export(
"memory".into(),
crate::core::EntityType::Memory(self.arbitrary_core_memory_type(u)?),
));
exports.insert("memory".into());
counts.memories += 1;
has_memory = true;
}
// `canonical_abi_realloc`
if counts.funcs < self.config.max_funcs
&& types.len() < self.config.max_types
&& u.ratio::<u8>(99, 100)?
{
let realloc_ty = Rc::new(crate::core::FuncType {
params: vec![ValType::I32, ValType::I32, ValType::I32, ValType::I32],
results: vec![ValType::I32],
});
let ty_idx = u32::try_from(types.len()).unwrap();
types.push(realloc_ty.clone());
defs.push(ModuleTypeDef::TypeDef(
crate::core::CompositeType::new_func(
realloc_ty.clone(),
false, // TODO: handle shared
),
));
defs.push(ModuleTypeDef::Export(
"canonical_abi_realloc".into(),
crate::core::EntityType::Func(ty_idx, realloc_ty),
));
exports.insert("canonical_abi_realloc".into());
counts.funcs += 1;
has_canonical_abi_realloc = true;
}
// `canonical_abi_free`
if counts.funcs < self.config.max_funcs
&& types.len() < self.config.max_types
&& u.ratio::<u8>(99, 100)?
{
let free_ty = Rc::new(crate::core::FuncType {
params: vec![ValType::I32, ValType::I32, ValType::I32],
results: vec![],
});
let ty_idx = u32::try_from(types.len()).unwrap();
types.push(free_ty.clone());
defs.push(ModuleTypeDef::TypeDef(
crate::core::CompositeType::new_func(
free_ty.clone(),
false, // TODO: handle shared
),
));
defs.push(ModuleTypeDef::Export(
"canonical_abi_free".into(),
crate::core::EntityType::Func(ty_idx, free_ty),
));
exports.insert("canonical_abi_free".into());
counts.funcs += 1;
has_canonical_abi_free = true;
}
let mut entity_choices: Vec<
fn(
&ComponentBuilder,
&mut Unstructured,
&mut EntityCounts,
&[Rc<crate::core::FuncType>],
) -> Result<crate::core::EntityType>,
> = Vec::with_capacity(5);
arbitrary_loop(u, 0, 100, |u| {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(false);
}
let max_choice = if types.len() < self.config.max_types {
// Check if the parent scope has core function types to alias
if !types.is_empty()
|| (!self.types.is_empty()
&& !self.types.last().unwrap().core_func_types.is_empty())
{
// Imports, exports, types, and aliases
3
} else {
// Imports, exports, and types
2
}
} else {
// Imports and exports
1
};
match u.int_in_range::<u8>(0..=max_choice)? {
// Import.
0 => {
let module = crate::limited_string(100, u)?;
let existing_module_imports = imports.entry(module.clone()).or_default();
let field = crate::unique_string(100, existing_module_imports, u)?;
let entity_type = match self.arbitrary_core_entity_type(
u,
&types,
&mut entity_choices,
&mut counts,
)? {
None => return Ok(false),
Some(x) => x,
};
defs.push(ModuleTypeDef::Import(crate::core::Import {
module,
field,
entity_type,
}));
}
// Export.
1 => {
let name = crate::unique_string(100, &mut exports, u)?;
let entity_ty = match self.arbitrary_core_entity_type(
u,
&types,
&mut entity_choices,
&mut counts,
)? {
None => return Ok(false),
Some(x) => x,
};
defs.push(ModuleTypeDef::Export(name, entity_ty));
}
// Type definition.
2 => {
let ty = arbitrary_func_type(
u,
&self.config,
&self.core_valtypes,
if self.config.multi_value_enabled {
None
} else {
Some(1)
},
0,
)?;
types.push(ty.clone());
defs.push(ModuleTypeDef::TypeDef(
crate::core::CompositeType::new_func(ty, false),
)); // TODO: handle shared
}
// Alias
3 => {
let (count, index, kind) = self.arbitrary_outer_core_type_alias(u, &types)?;
let ty = match &kind {
CoreOuterAliasKind::Type(ty) => ty.clone(),
};
types.push(ty);
defs.push(ModuleTypeDef::OuterAlias {
count,
i: index,
kind,
});
}
_ => unreachable!(),
}
Ok(true)
})?;
Ok(Rc::new(ModuleType {
defs,
has_memory,
has_canonical_abi_realloc,
has_canonical_abi_free,
}))
}
fn arbitrary_core_entity_type(
&self,
u: &mut Unstructured,
types: &[Rc<crate::core::FuncType>],
choices: &mut Vec<
fn(
&ComponentBuilder,
&mut Unstructured,
&mut EntityCounts,
&[Rc<crate::core::FuncType>],
) -> Result<crate::core::EntityType>,
>,
counts: &mut EntityCounts,
) -> Result<Option<crate::core::EntityType>> {
choices.clear();
if counts.globals < self.config.max_globals {
choices.push(|c, u, counts, _types| {
counts.globals += 1;
Ok(crate::core::EntityType::Global(
c.arbitrary_core_global_type(u)?,
))
});
}
if counts.tables < self.config.max_tables {
choices.push(|c, u, counts, _types| {
counts.tables += 1;
Ok(crate::core::EntityType::Table(
c.arbitrary_core_table_type(u)?,
))
});
}
if counts.memories < self.config.max_memories {
choices.push(|c, u, counts, _types| {
counts.memories += 1;
Ok(crate::core::EntityType::Memory(
c.arbitrary_core_memory_type(u)?,
))
});
}
if types.iter().any(|ty| ty.results.is_empty())
&& self.config.exceptions_enabled
&& counts.tags < self.config.max_tags
{
choices.push(|c, u, counts, types| {
counts.tags += 1;
let tag_func_types = types
.iter()
.enumerate()
.filter(|(_, ty)| ty.results.is_empty())
.map(|(i, _)| u32::try_from(i).unwrap())
.collect::<Vec<_>>();
Ok(crate::core::EntityType::Tag(
crate::core::arbitrary_tag_type(u, &tag_func_types, |idx| {
types[usize::try_from(idx).unwrap()].clone()
})?,
))
});
}
if !types.is_empty() && counts.funcs < self.config.max_funcs {
choices.push(|c, u, counts, types| {
counts.funcs += 1;
let ty_idx = u.int_in_range(0..=u32::try_from(types.len() - 1).unwrap())?;
let ty = types[ty_idx as usize].clone();
Ok(crate::core::EntityType::Func(ty_idx, ty))
});
}
if choices.is_empty() {
return Ok(None);
}
let f = u.choose(choices)?;
let ty = f(self, u, counts, types)?;
Ok(Some(ty))
}
fn arbitrary_core_valtype(&self, u: &mut Unstructured) -> Result<ValType> {
Ok(*u.choose(&self.core_valtypes)?)
}
fn arbitrary_core_global_type(&self, u: &mut Unstructured) -> Result<crate::core::GlobalType> {
Ok(crate::core::GlobalType {
val_type: self.arbitrary_core_valtype(u)?,
mutable: u.arbitrary()?,
shared: false,
})
}
fn arbitrary_core_table_type(&self, u: &mut Unstructured) -> Result<crate::core::TableType> {
crate::core::arbitrary_table_type(u, &self.config, None)
}
fn arbitrary_core_memory_type(&self, u: &mut Unstructured) -> Result<crate::core::MemoryType> {
crate::core::arbitrary_memtype(u, &self.config)
}
fn with_types_scope<T>(&mut self, f: impl FnOnce(&mut Self) -> Result<T>) -> Result<T> {
self.types.push(Default::default());
let result = f(self);
self.types.pop();
result
}
fn current_type_scope(&self) -> &TypesScope {
self.types.last().unwrap()
}
fn current_type_scope_mut(&mut self) -> &mut TypesScope {
self.types.last_mut().unwrap()
}
fn outer_types_scope(&self, count: u32) -> &TypesScope {
&self.types[self.types.len() - 1 - usize::try_from(count).unwrap()]
}
fn outer_type(&self, count: u32, i: u32) -> &Rc<Type> {
&self.outer_types_scope(count).types[usize::try_from(i).unwrap()]
}
fn arbitrary_component_type(
&mut self,
u: &mut Unstructured,
type_fuel: &mut u32,
) -> Result<Rc<ComponentType>> {
let mut defs = vec![];
let mut imports = HashSet::new();
let mut import_urls = HashSet::new();
let mut exports = HashSet::new();
let mut export_urls = HashSet::new();
self.with_types_scope(|me| {
arbitrary_loop(u, 0, 100, |u| {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(false);
}
if me.current_type_scope().can_ref_type() && u.int_in_range::<u8>(0..=3)? == 0 {
if let Some(ty) = me.arbitrary_type_ref(u, true, true)? {
// Imports.
let name = crate::unique_kebab_string(100, &mut imports, u)?;
let url = if u.arbitrary()? {
Some(crate::unique_url(100, &mut import_urls, u)?)
} else {
None
};
defs.push(ComponentTypeDef::Import(Import { name, url, ty }));
return Ok(true);
}
// Can't reference an arbitrary type, fallback to another definition.
}
// Type definitions, exports, and aliases.
let def =
me.arbitrary_instance_type_def(u, &mut exports, &mut export_urls, type_fuel)?;
defs.push(def.into());
Ok(true)
})
})?;
Ok(Rc::new(ComponentType { defs }))
}
fn arbitrary_instance_type(
&mut self,
u: &mut Unstructured,
type_fuel: &mut u32,
) -> Result<Rc<InstanceType>> {
let mut defs = vec![];
let mut exports = HashSet::new();
let mut export_urls = HashSet::new();
self.with_types_scope(|me| {
arbitrary_loop(u, 0, 100, |u| {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(false);
}
defs.push(me.arbitrary_instance_type_def(
u,
&mut exports,
&mut export_urls,
type_fuel,
)?);
Ok(true)
})
})?;
Ok(Rc::new(InstanceType { defs }))
}
fn arbitrary_instance_type_def(
&mut self,
u: &mut Unstructured,
exports: &mut HashSet<String>,
export_urls: &mut HashSet<String>,
type_fuel: &mut u32,
) -> Result<InstanceTypeDecl> {
let mut choices: Vec<
fn(
&mut ComponentBuilder,
&mut HashSet<String>,
&mut HashSet<String>,
&mut Unstructured,
&mut u32,
) -> Result<InstanceTypeDecl>,
> = Vec::with_capacity(3);
// Export.
if self.current_type_scope().can_ref_type() {
choices.push(|me, exports, export_urls, u, _type_fuel| {
let ty = me.arbitrary_type_ref(u, false, true)?.unwrap();
if let ComponentTypeRef::Type(TypeBounds::Eq(idx)) = ty {
let ty = me.current_type_scope().get(idx).clone();
me.current_type_scope_mut().push(ty);
}
Ok(InstanceTypeDecl::Export {
name: crate::unique_kebab_string(100, exports, u)?,
url: if u.arbitrary()? {
Some(crate::unique_url(100, export_urls, u)?)
} else {
None
},
ty,
})
});
}
// Outer type alias.
if self
.types
.iter()
.any(|scope| !scope.types.is_empty() || !scope.core_types.is_empty())
{
choices.push(|me, _exports, _export_urls, u, _type_fuel| {
let alias = me.arbitrary_outer_type_alias(u)?;
match &alias {
Alias::Outer {
kind: OuterAliasKind::Type(ty),
..
} => me.current_type_scope_mut().push(ty.clone()),
Alias::Outer {
kind: OuterAliasKind::CoreType(ty),
..
} => me.current_type_scope_mut().push_core(ty.clone()),
_ => unreachable!(),
};
Ok(InstanceTypeDecl::Alias(alias))
});
}
// Core type definition.
choices.push(|me, _exports, _export_urls, u, type_fuel| {
let ty = me.arbitrary_core_type(u, type_fuel)?;
me.current_type_scope_mut().push_core(ty.clone());
Ok(InstanceTypeDecl::CoreType(ty))
});
// Type definition.
if self.types.len() < self.config.max_nesting_depth {
choices.push(|me, _exports, _export_urls, u, type_fuel| {
let ty = me.arbitrary_type(u, type_fuel)?;
me.current_type_scope_mut().push(ty.clone());
Ok(InstanceTypeDecl::Type(ty))
});
}
let f = u.choose(&choices)?;
f(self, exports, export_urls, u, type_fuel)
}
fn arbitrary_outer_core_type_alias(
&self,
u: &mut Unstructured,
local_types: &[Rc<crate::core::FuncType>],
) -> Result<(u32, u32, CoreOuterAliasKind)> {
let enclosing_type_len = if !self.types.is_empty() {
self.types.last().unwrap().core_func_types.len()
} else {
0
};
assert!(!local_types.is_empty() || enclosing_type_len > 0);
let max = enclosing_type_len + local_types.len() - 1;
let i = u.int_in_range(0..=max)?;
let (count, index, ty) = if i < enclosing_type_len {
let enclosing = self.types.last().unwrap();
let index = enclosing.core_func_types[i];
(
1,
index,
match enclosing.get_core(index).as_ref() {
CoreType::Func(ty) => ty.clone(),
CoreType::Module(_) => unreachable!(),
},
)
} else if i - enclosing_type_len < local_types.len() {
let i = i - enclosing_type_len;
(0, u32::try_from(i).unwrap(), local_types[i].clone())
} else {
unreachable!()
};
Ok((count, index, CoreOuterAliasKind::Type(ty)))
}
fn arbitrary_outer_type_alias(&self, u: &mut Unstructured) -> Result<Alias> {
let non_empty_types_scopes: Vec<_> = self
.types
.iter()
.rev()
.enumerate()
.filter(|(_, scope)| !scope.types.is_empty() || !scope.core_types.is_empty())
.collect();
assert!(
!non_empty_types_scopes.is_empty(),
"precondition: there are non-empty types scopes"
);
let (count, scope) = u.choose(&non_empty_types_scopes)?;
let count = u32::try_from(*count).unwrap();
assert!(!scope.types.is_empty() || !scope.core_types.is_empty());
let max_type_in_scope = scope.types.len() + scope.core_types.len() - 1;
let i = u.int_in_range(0..=max_type_in_scope)?;
let (i, kind) = if i < scope.types.len() {
let i = u32::try_from(i).unwrap();
(i, OuterAliasKind::Type(Rc::clone(scope.get(i))))
} else if i - scope.types.len() < scope.core_types.len() {
let i = u32::try_from(i - scope.types.len()).unwrap();
(i, OuterAliasKind::CoreType(Rc::clone(scope.get_core(i))))
} else {
unreachable!()
};
Ok(Alias::Outer { count, i, kind })
}
fn arbitrary_func_type(
&self,
u: &mut Unstructured,
type_fuel: &mut u32,
) -> Result<Rc<FuncType>> {
let mut params = Vec::new();
let mut results = Vec::new();
let mut names = HashSet::new();
// Note: parameters are currently limited to a maximum of 16
// because any additional parameters will require indirect access
// via a pointer argument; when this occurs, validation of any
// lowered function will fail because it will be missing a
// memory option (not yet implemented).
//
// When options are correctly specified on canonical functions,
// we should increase this maximum to test indirect parameter
// passing.
arbitrary_loop(u, 0, 16, |u| {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(false);
}
let name = crate::unique_kebab_string(100, &mut names, u)?;
let ty = self.arbitrary_component_val_type(u)?;
params.push((name, ty));
Ok(true)
})?;
names.clear();
// Likewise, the limit for results is 1 before the memory option is
// required. When the memory option is implemented, this restriction
// should be relaxed.
arbitrary_loop(u, 0, 1, |u| {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(false);
}
// If the result list is empty (i.e. first push), then arbitrarily give
// the result a name. Otherwise, all of the subsequent items must be named.
let name = if results.is_empty() {
// Most of the time we should have a single, unnamed result.
u.ratio::<u8>(10, 100)?
.then(|| crate::unique_kebab_string(100, &mut names, u))
.transpose()?
} else {
Some(crate::unique_kebab_string(100, &mut names, u)?)
};
let ty = self.arbitrary_component_val_type(u)?;
results.push((name, ty));
// There can be only one unnamed result.
if results.len() == 1 && results[0].0.is_none() {
return Ok(false);
}
Ok(true)
})?;
Ok(Rc::new(FuncType { params, results }))
}
fn arbitrary_component_val_type(&self, u: &mut Unstructured) -> Result<ComponentValType> {
let max_choices = if self.current_type_scope().defined_types.is_empty() {
0
} else {
1
};
match u.int_in_range(0..=max_choices)? {
0 => Ok(ComponentValType::Primitive(
self.arbitrary_primitive_val_type(u)?,
)),
1 => {
let index = *u.choose(&self.current_type_scope().defined_types)?;
let ty = Rc::clone(self.current_type_scope().get(index));
Ok(ComponentValType::Type(index))
}
_ => unreachable!(),
}
}
fn arbitrary_primitive_val_type(&self, u: &mut Unstructured) -> Result<PrimitiveValType> {
match u.int_in_range(0..=12)? {
0 => Ok(PrimitiveValType::Bool),
1 => Ok(PrimitiveValType::S8),
2 => Ok(PrimitiveValType::U8),
3 => Ok(PrimitiveValType::S16),
4 => Ok(PrimitiveValType::U16),
5 => Ok(PrimitiveValType::S32),
6 => Ok(PrimitiveValType::U32),
7 => Ok(PrimitiveValType::S64),
8 => Ok(PrimitiveValType::U64),
9 => Ok(PrimitiveValType::F32),
10 => Ok(PrimitiveValType::F64),
11 => Ok(PrimitiveValType::Char),
12 => Ok(PrimitiveValType::String),
_ => unreachable!(),
}
}
fn arbitrary_record_type(
&self,
u: &mut Unstructured,
type_fuel: &mut u32,
) -> Result<RecordType> {
let mut fields = vec![];
let mut field_names = HashSet::new();
arbitrary_loop(u, 0, 100, |u| {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(false);
}
let name = crate::unique_kebab_string(100, &mut field_names, u)?;
let ty = self.arbitrary_component_val_type(u)?;
fields.push((name, ty));
Ok(true)
})?;
Ok(RecordType { fields })
}
fn arbitrary_variant_type(
&self,
u: &mut Unstructured,
type_fuel: &mut u32,
) -> Result<VariantType> {
let mut cases = vec![];
let mut case_names = HashSet::new();
arbitrary_loop(u, 1, 100, |u| {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(false);
}
let name = crate::unique_kebab_string(100, &mut case_names, u)?;
let ty = u
.arbitrary::<bool>()?
.then(|| self.arbitrary_component_val_type(u))
.transpose()?;
let refines = if !cases.is_empty() && u.arbitrary()? {
let max_cases = u32::try_from(cases.len() - 1).unwrap();
Some(u.int_in_range(0..=max_cases)?)
} else {
None
};
cases.push((name, ty, refines));
Ok(true)
})?;
Ok(VariantType { cases })
}
fn arbitrary_list_type(&self, u: &mut Unstructured) -> Result<ListType> {
Ok(ListType {
elem_ty: self.arbitrary_component_val_type(u)?,
})
}
fn arbitrary_tuple_type(&self, u: &mut Unstructured, type_fuel: &mut u32) -> Result<TupleType> {
let mut fields = vec![];
arbitrary_loop(u, 0, 100, |u| {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(false);
}
fields.push(self.arbitrary_component_val_type(u)?);
Ok(true)
})?;
Ok(TupleType { fields })
}
fn arbitrary_flags_type(&self, u: &mut Unstructured, type_fuel: &mut u32) -> Result<FlagsType> {
let mut fields = vec![];
let mut field_names = HashSet::new();
arbitrary_loop(u, 0, 100, |u| {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(false);
}
fields.push(crate::unique_kebab_string(100, &mut field_names, u)?);
Ok(true)
})?;
Ok(FlagsType { fields })
}
fn arbitrary_enum_type(&self, u: &mut Unstructured, type_fuel: &mut u32) -> Result<EnumType> {
let mut variants = vec![];
let mut variant_names = HashSet::new();
arbitrary_loop(u, 1, 100, |u| {
*type_fuel = type_fuel.saturating_sub(1);
if *type_fuel == 0 {
return Ok(false);
}
variants.push(crate::unique_kebab_string(100, &mut variant_names, u)?);
Ok(true)
})?;
Ok(EnumType { variants })
}
fn arbitrary_option_type(&self, u: &mut Unstructured) -> Result<OptionType> {
Ok(OptionType {
inner_ty: self.arbitrary_component_val_type(u)?,
})
}
fn arbitrary_result_type(&self, u: &mut Unstructured) -> Result<ResultType> {
Ok(ResultType {
ok_ty: u
.arbitrary::<bool>()?
.then(|| self.arbitrary_component_val_type(u))
.transpose()?,
err_ty: u
.arbitrary::<bool>()?
.then(|| self.arbitrary_component_val_type(u))
.transpose()?,
})
}
fn arbitrary_defined_type(
&self,
u: &mut Unstructured,
type_fuel: &mut u32,
) -> Result<DefinedType> {
match u.int_in_range(0..=8)? {
0 => Ok(DefinedType::Primitive(
self.arbitrary_primitive_val_type(u)?,
)),
1 => Ok(DefinedType::Record(
self.arbitrary_record_type(u, type_fuel)?,
)),
2 => Ok(DefinedType::Variant(
self.arbitrary_variant_type(u, type_fuel)?,
)),
3 => Ok(DefinedType::List(self.arbitrary_list_type(u)?)),
4 => Ok(DefinedType::Tuple(self.arbitrary_tuple_type(u, type_fuel)?)),
5 => Ok(DefinedType::Flags(self.arbitrary_flags_type(u, type_fuel)?)),
6 => Ok(DefinedType::Enum(self.arbitrary_enum_type(u, type_fuel)?)),
7 => Ok(DefinedType::Option(self.arbitrary_option_type(u)?)),
8 => Ok(DefinedType::Result(self.arbitrary_result_type(u)?)),
_ => unreachable!(),
}
}
fn push_import(&mut self, name: String, url: Option<String>, ty: ComponentTypeRef) {
let nth = match self.ensure_section(
|sec| matches!(sec, Section::Import(_)),
|| Section::Import(ImportSection { imports: vec![] }),
) {
Section::Import(sec) => {
sec.imports.push(Import { name, url, ty });
sec.imports.len() - 1
}
_ => unreachable!(),
};
let section_index = self.component().component.sections.len() - 1;
match ty {
ComponentTypeRef::Module(_) => {
self.total_modules += 1;
self.component_mut().modules.push((section_index, nth));
}
ComponentTypeRef::Func(ty_index) => {
let func_ty = match self.current_type_scope().get(ty_index).as_ref() {
Type::Func(ty) => ty.clone(),
_ => unreachable!(),
};
if func_ty.is_scalar() {
let func_index = u32::try_from(self.component().component_funcs.len()).unwrap();
self.component_mut().scalar_component_funcs.push(func_index);
}
let func_index = u32::try_from(self.component().funcs.len()).unwrap();
self.component_mut()
.funcs
.push(ComponentOrCoreFuncType::Component(func_ty));
self.component_mut().component_funcs.push(func_index);
}
ComponentTypeRef::Value(ty) => {
self.total_values += 1;
self.component_mut().values.push(ty);
}
ComponentTypeRef::Type(TypeBounds::Eq(ty_index)) => {
let ty = self.current_type_scope().get(ty_index).clone();
self.current_type_scope_mut().push(ty);
}
ComponentTypeRef::Type(TypeBounds::SubResource) => {
unimplemented!()
}
ComponentTypeRef::Instance(ty_index) => {
let instance_ty = match self.current_type_scope().get(ty_index).as_ref() {
Type::Instance(ty) => ty.clone(),
_ => unreachable!(),
};
self.total_instances += 1;
self.component_mut()
.instances
.push(ComponentOrCoreInstanceType::Component(instance_ty));
}
ComponentTypeRef::Component(_) => {
self.total_components += 1;
self.component_mut().components.push((section_index, nth));
}
}
}
fn core_function_type(&self, core_func_index: u32) -> &Rc<crate::core::FuncType> {
self.component().funcs[self.component().core_funcs[core_func_index as usize] as usize]
.as_core()
}
fn component_function_type(&self, func_index: u32) -> &Rc<FuncType> {
self.component().funcs[self.component().component_funcs[func_index as usize] as usize]
.as_component()
}
fn push_func(&mut self, func: Func) {
let nth = match self.component_mut().component.sections.last_mut() {
Some(Section::Canonical(CanonicalSection { funcs })) => funcs.len(),
_ => {
self.push_section(Section::Canonical(CanonicalSection { funcs: vec![] }));
0
}
};
let section_index = self.component().component.sections.len() - 1;
let func_index = u32::try_from(self.component().funcs.len()).unwrap();
let ty = match &func {
Func::CanonLift { func_ty, .. } => {
let ty = Rc::clone(self.current_type_scope().get_func(*func_ty));
if ty.is_scalar() {
let func_index = u32::try_from(self.component().component_funcs.len()).unwrap();
self.component_mut().scalar_component_funcs.push(func_index);
}
self.component_mut().component_funcs.push(func_index);
ComponentOrCoreFuncType::Component(ty)
}
Func::CanonLower {
func_index: comp_func_index,
..
} => {
let comp_func_ty = self.component_function_type(*comp_func_index);
let core_func_ty = canonical_abi_for(comp_func_ty);
self.component_mut().core_funcs.push(func_index);
ComponentOrCoreFuncType::Core(core_func_ty)
}
};
self.component_mut().funcs.push(ty);
match self.component_mut().component.sections.last_mut() {
Some(Section::Canonical(CanonicalSection { funcs })) => funcs.push(func),
_ => unreachable!(),
}
}
fn arbitrary_import_section(&mut self, u: &mut Unstructured) -> Result<Step> {
self.push_section(Section::Import(ImportSection { imports: vec![] }));
let min = if self.fill_minimums {
self.config
.min_imports
.saturating_sub(self.component().num_imports)
} else {
// Allow generating empty sections. We can always fill in the required
// minimum later.
0
};
let max = self.config.max_imports - self.component().num_imports;
crate::arbitrary_loop(u, min, max, |u| {
match self.arbitrary_type_ref(u, true, false)? {
Some(ty) => {
let name =
crate::unique_kebab_string(100, &mut self.component_mut().import_names, u)?;
let url = if u.arbitrary()? {
Some(crate::unique_url(
100,
&mut self.component_mut().import_urls,
u,
)?)
} else {
None
};
self.push_import(name, url, ty);
Ok(true)
}
None => Ok(false),
}
})?;
Ok(Step::StillBuilding)
}
fn arbitrary_canonical_section(&mut self, u: &mut Unstructured) -> Result<Step> {
self.push_section(Section::Canonical(CanonicalSection { funcs: vec![] }));
let min = if self.fill_minimums {
self.config
.min_funcs
.saturating_sub(self.component().funcs.len())
} else {
// Allow generating empty sections. We can always fill in the
// required minimum later.
0
};
let max = self.config.max_funcs - self.component().funcs.len();
let mut choices: Vec<fn(&mut Unstructured, &mut ComponentBuilder) -> Result<Option<Func>>> =
Vec::with_capacity(2);
crate::arbitrary_loop(u, min, max, |u| {
choices.clear();
// NB: We only lift/lower scalar component functions.
//
// If we generated lifting and lowering of compound value types,
// the probability of generating a corresponding Wasm module that
// generates valid instances of the compound value types would
// be vanishingly tiny (e.g. for `list<string>` we would have to
// generate a core Wasm module that correctly produces a pointer and
// length for a memory region that itself is a series of pointers
// and lengths of valid strings, as well as `canonical_abi_realloc`
// and `canonical_abi_free` functions that do the right thing).
//
// This is a pretty serious limitation of `wasm-smith`'s component
// types support, but it is one we are intentionally
// accepting. `wasm-smith` will focus on generating arbitrary
// component sections, structures, and import/export topologies; not
// component functions and core Wasm implementations of component
// functions. In the future, we intend to build a new, distinct test
// case generator specifically for exercising component functions
// and the canonical ABI. This new generator won't emit arbitrary
// component sections, structures, or import/export topologies, and
// will instead leave that to `wasm-smith`.
if !self.component().scalar_component_funcs.is_empty() {
choices.push(|u, c| {
let func_index = *u.choose(&c.component().scalar_component_funcs)?;
Ok(Some(Func::CanonLower {
// Scalar component functions don't use any canonical options.
options: vec![],
func_index,
}))
});
}
if !self.component().core_funcs.is_empty() {
choices.push(|u, c| {
let core_func_index = u.int_in_range(
0..=u32::try_from(c.component().core_funcs.len() - 1).unwrap(),
)?;
let core_func_ty = c.core_function_type(core_func_index);
let comp_func_ty = inverse_scalar_canonical_abi_for(u, core_func_ty)?;
let func_ty = if let Some(indices) = c
.current_type_scope()
.func_type_to_indices
.get(&comp_func_ty)
{
// If we've already defined this component function type
// one or more times, then choose one of those
// definitions arbitrarily.
debug_assert!(!indices.is_empty());
*u.choose(indices)?
} else if c.current_type_scope().types.len() < c.config.max_types {
// If we haven't already defined this component function
// type, and we haven't defined the configured maximum
// amount of types yet, then just define this type.
let ty = Rc::new(Type::Func(Rc::new(comp_func_ty)));
c.push_type(ty)
} else {
// Otherwise, give up on lifting this function.
return Ok(None);
};
Ok(Some(Func::CanonLift {
func_ty,
// Scalar functions don't use any canonical options.
options: vec![],
core_func_index,
}))
});
}
if choices.is_empty() {
return Ok(false);
}
let f = u.choose(&choices)?;
if let Some(func) = f(u, self)? {
self.push_func(func);
}
Ok(true)
})?;
Ok(Step::StillBuilding)
}
fn arbitrary_core_module_section(&mut self, u: &mut Unstructured) -> Result<Step> {
let module = crate::core::Module::new_internal(
self.config.clone(),
u,
crate::core::DuplicateImportsBehavior::Disallowed,
)?;
self.push_section(Section::CoreModule(module));
self.total_modules += 1;
Ok(Step::StillBuilding)
}
fn arbitrary_component_section(&mut self, u: &mut Unstructured) -> Result<Step> {
self.types.push(TypesScope::default());
self.components.push(ComponentContext::empty());
self.total_components += 1;
Ok(Step::StillBuilding)
}
fn arbitrary_instance_section(&mut self, u: &mut Unstructured) -> Result<()> {
todo!()
}
fn arbitrary_export_section(&mut self, u: &mut Unstructured) -> Result<()> {
todo!()
}
fn arbitrary_start_section(&mut self, u: &mut Unstructured) -> Result<()> {
todo!()
}
fn arbitrary_alias_section(&mut self, u: &mut Unstructured) -> Result<()> {
todo!()
}
}
fn canonical_abi_for(func_ty: &FuncType) -> Rc<crate::core::FuncType> {
let to_core_ty = |ty| match ty {
ComponentValType::Primitive(prim_ty) => match prim_ty {
PrimitiveValType::Char
| PrimitiveValType::Bool
| PrimitiveValType::S8
| PrimitiveValType::U8
| PrimitiveValType::S16
| PrimitiveValType::U16
| PrimitiveValType::S32
| PrimitiveValType::U32 => ValType::I32,
PrimitiveValType::S64 | PrimitiveValType::U64 => ValType::I64,
PrimitiveValType::F32 => ValType::F32,
PrimitiveValType::F64 => ValType::F64,
PrimitiveValType::String => {
unimplemented!("non-scalar types are not supported yet")
}
},
ComponentValType::Type(_) => unimplemented!("non-scalar types are not supported yet"),
};
Rc::new(crate::core::FuncType {
params: func_ty
.params
.iter()
.map(|(_, ty)| to_core_ty(*ty))
.collect(),
results: func_ty
.results
.iter()
.map(|(_, ty)| to_core_ty(*ty))
.collect(),
})
}
fn inverse_scalar_canonical_abi_for(
u: &mut Unstructured,
core_func_ty: &crate::core::FuncType,
) -> Result<FuncType> {
let from_core_ty = |u: &mut Unstructured, core_ty| match core_ty {
ValType::I32 => u
.choose(&[
ComponentValType::Primitive(PrimitiveValType::Char),
ComponentValType::Primitive(PrimitiveValType::Bool),
ComponentValType::Primitive(PrimitiveValType::S8),
ComponentValType::Primitive(PrimitiveValType::U8),
ComponentValType::Primitive(PrimitiveValType::S16),
ComponentValType::Primitive(PrimitiveValType::U16),
ComponentValType::Primitive(PrimitiveValType::S32),
ComponentValType::Primitive(PrimitiveValType::U32),
])
.cloned(),
ValType::I64 => u
.choose(&[
ComponentValType::Primitive(PrimitiveValType::S64),
ComponentValType::Primitive(PrimitiveValType::U64),
])
.cloned(),
ValType::F32 => Ok(ComponentValType::Primitive(PrimitiveValType::F32)),
ValType::F64 => Ok(ComponentValType::Primitive(PrimitiveValType::F64)),
ValType::V128 | ValType::Ref(_) => {
unreachable!("not used in canonical ABI")
}
};
let mut names = HashSet::default();
let mut params = vec![];
for core_ty in &core_func_ty.params {
params.push((
crate::unique_kebab_string(100, &mut names, u)?,
from_core_ty(u, *core_ty)?,
));
}
names.clear();
let results = match core_func_ty.results.len() {
0 => Vec::new(),
1 => vec![(
if u.arbitrary()? {
Some(crate::unique_kebab_string(100, &mut names, u)?)
} else {
None
},
from_core_ty(u, core_func_ty.results[0])?,
)],
_ => unimplemented!("non-scalar types are not supported yet"),
};
Ok(FuncType { params, results })
}
#[derive(Debug)]
enum Section {
Custom(CustomSection),
CoreModule(crate::Module),
CoreInstance(CoreInstanceSection),
CoreType(CoreTypeSection),
Component(Component),
Instance(InstanceSection),
Alias(AliasSection),
Type(TypeSection),
Canonical(CanonicalSection),
Start(StartSection),
Import(ImportSection),
Export(ExportSection),
}
#[derive(Debug)]
struct CustomSection {
name: String,
data: Vec<u8>,
}
impl<'a> Arbitrary<'a> for CustomSection {
fn arbitrary(u: &mut Unstructured<'a>) -> Result<Self> {
let name = crate::limited_string(1_000, u)?;
let data = u.arbitrary()?;
Ok(CustomSection { name, data })
}
}
#[derive(Debug)]
struct TypeSection {
types: Vec<Rc<Type>>,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum CoreType {
Func(Rc<crate::core::FuncType>),
Module(Rc<ModuleType>),
}
#[derive(Clone, Debug, PartialEq, Eq, Hash, Default)]
struct ModuleType {
defs: Vec<ModuleTypeDef>,
has_memory: bool,
has_canonical_abi_realloc: bool,
has_canonical_abi_free: bool,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum ModuleTypeDef {
TypeDef(crate::core::CompositeType),
Import(crate::core::Import),
OuterAlias {
count: u32,
i: u32,
kind: CoreOuterAliasKind,
},
Export(String, crate::core::EntityType),
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum Type {
Defined(DefinedType),
Func(Rc<FuncType>),
Component(Rc<ComponentType>),
Instance(Rc<InstanceType>),
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum CoreInstanceExportAliasKind {
Func,
Table,
Memory,
Global,
Tag,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum CoreOuterAliasKind {
Type(Rc<crate::core::FuncType>),
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum Alias {
InstanceExport {
instance: u32,
name: String,
kind: InstanceExportAliasKind,
},
CoreInstanceExport {
instance: u32,
name: String,
kind: CoreInstanceExportAliasKind,
},
Outer {
count: u32,
i: u32,
kind: OuterAliasKind,
},
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum InstanceExportAliasKind {
Module,
Component,
Instance,
Func,
Value,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum OuterAliasKind {
Module,
Component,
CoreType(Rc<CoreType>),
Type(Rc<Type>),
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct ComponentType {
defs: Vec<ComponentTypeDef>,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum ComponentTypeDef {
CoreType(Rc<CoreType>),
Type(Rc<Type>),
Alias(Alias),
Import(Import),
Export {
name: String,
url: Option<String>,
ty: ComponentTypeRef,
},
}
impl From<InstanceTypeDecl> for ComponentTypeDef {
fn from(def: InstanceTypeDecl) -> Self {
match def {
InstanceTypeDecl::CoreType(t) => Self::CoreType(t),
InstanceTypeDecl::Type(t) => Self::Type(t),
InstanceTypeDecl::Export { name, url, ty } => Self::Export { name, url, ty },
InstanceTypeDecl::Alias(a) => Self::Alias(a),
}
}
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct InstanceType {
defs: Vec<InstanceTypeDecl>,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum InstanceTypeDecl {
CoreType(Rc<CoreType>),
Type(Rc<Type>),
Alias(Alias),
Export {
name: String,
url: Option<String>,
ty: ComponentTypeRef,
},
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct FuncType {
params: Vec<(String, ComponentValType)>,
results: Vec<(Option<String>, ComponentValType)>,
}
impl FuncType {
fn unnamed_result_ty(&self) -> Option<ComponentValType> {
if self.results.len() == 1 {
let (name, ty) = &self.results[0];
if name.is_none() {
return Some(*ty);
}
}
None
}
fn is_scalar(&self) -> bool {
self.params.iter().all(|(_, ty)| is_scalar(ty))
&& self.results.len() == 1
&& is_scalar(&self.results[0].1)
}
}
fn is_scalar(ty: &ComponentValType) -> bool {
match ty {
ComponentValType::Primitive(prim) => match prim {
PrimitiveValType::Bool
| PrimitiveValType::S8
| PrimitiveValType::U8
| PrimitiveValType::S16
| PrimitiveValType::U16
| PrimitiveValType::S32
| PrimitiveValType::U32
| PrimitiveValType::S64
| PrimitiveValType::U64
| PrimitiveValType::F32
| PrimitiveValType::F64
| PrimitiveValType::Char => true,
PrimitiveValType::String => false,
},
ComponentValType::Type(_) => false,
}
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
enum DefinedType {
Primitive(PrimitiveValType),
Record(RecordType),
Variant(VariantType),
List(ListType),
Tuple(TupleType),
Flags(FlagsType),
Enum(EnumType),
Option(OptionType),
Result(ResultType),
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct RecordType {
fields: Vec<(String, ComponentValType)>,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct VariantType {
cases: Vec<(String, Option<ComponentValType>, Option<u32>)>,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct ListType {
elem_ty: ComponentValType,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct TupleType {
fields: Vec<ComponentValType>,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct FlagsType {
fields: Vec<String>,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct EnumType {
variants: Vec<String>,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct OptionType {
inner_ty: ComponentValType,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct ResultType {
ok_ty: Option<ComponentValType>,
err_ty: Option<ComponentValType>,
}
#[derive(Debug)]
struct ImportSection {
imports: Vec<Import>,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
struct Import {
name: String,
url: Option<String>,
ty: ComponentTypeRef,
}
#[derive(Debug)]
struct CanonicalSection {
funcs: Vec<Func>,
}
#[derive(Debug)]
enum Func {
CanonLift {
func_ty: u32,
options: Vec<CanonOpt>,
core_func_index: u32,
},
CanonLower {
options: Vec<CanonOpt>,
func_index: u32,
},
}
#[derive(Debug)]
enum CanonOpt {
StringUtf8,
StringUtf16,
StringLatin1Utf16,
Memory(u32),
Realloc(u32),
PostReturn(u32),
}
#[derive(Debug)]
struct InstanceSection {}
#[derive(Debug)]
struct ExportSection {}
#[derive(Debug)]
struct StartSection {}
#[derive(Debug)]
struct AliasSection {}
#[derive(Debug)]
struct CoreInstanceSection {}
#[derive(Debug)]
struct CoreTypeSection {
types: Vec<Rc<CoreType>>,
}
fn arbitrary_func_type(
u: &mut Unstructured,
config: &Config,
valtypes: &[ValType],
max_results: Option<usize>,
type_ref_limit: u32,
) -> Result<Rc<crate::core::FuncType>> {
let mut params = vec![];
let mut results = vec![];
arbitrary_loop(u, 0, 20, |u| {
params.push(arbitrary_valtype(u, config, valtypes, type_ref_limit)?);
Ok(true)
})?;
arbitrary_loop(u, 0, max_results.unwrap_or(20), |u| {
results.push(arbitrary_valtype(u, config, valtypes, type_ref_limit)?);
Ok(true)
})?;
Ok(Rc::new(crate::core::FuncType { params, results }))
}
fn arbitrary_valtype(
u: &mut Unstructured,
config: &Config,
valtypes: &[ValType],
type_ref_limit: u32,
) -> Result<ValType> {
if config.gc_enabled && type_ref_limit > 0 && u.ratio(1, 20)? {
Ok(ValType::Ref(RefType {
// TODO: For now, only create allow nullable reference
// types. Eventually we should support non-nullable reference types,
// but this means that we will also need to recognize when it is
// impossible to create an instance of the reference (eg `(ref
// nofunc)` has no instances, and self-referential types that
// contain a non-null self-reference are also impossible to create).
nullable: true,
heap_type: HeapType::Concrete(u.int_in_range(0..=type_ref_limit - 1)?),
}))
} else {
Ok(*u.choose(valtypes)?)
}
}