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Deduplicate some size/align calculations (#4658)

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This commit is an effort to reduce the amount of complexity around
managing the size/alignment calculations of types in the canonical ABI.
Previously the logic for the size/alignment of a type was spread out
across a number of locations. While each individual calculation is not
really the most complicated thing in the world having the duplication in
so many places was constantly worrying me.

I've opted in this commit to centralize all of this within the runtime
at least, and now there's only one "duplicate" of this information in
the fuzzing infrastructure which is to some degree less important to
deduplicate. This commit introduces a new `CanonicalAbiInfo` type to
house all abi size/align information for both memory32 and memory64.
This new type is then used pervasively throughout fused adapter
compilation, dynamic `Val` management, and typed functions. This type
was also able to reduce the complexity of the macro-generated code
meaning that even `wasmtime-component-macro` is performing less math
than it was before.

One other major feature of this commit is that this ABI information is
now saved within a `ComponentTypes` structure. This avoids recursive
querying of size/align information frequently and instead effectively
caching it. This was a worry I had for the fused adapter compiler which
frequently sought out size/align information and would recursively
descend each type tree each time. The `fact-valid-module` fuzzer is now
nearly 10x faster in terms of iterations/s which I suspect is due to
this caching.
This commit is contained in:
Alex Crichton
2022-08-09 14:52:20 -05:00
committed by GitHub
parent d5de91b953
commit bd70dbebbd
15 changed files with 845 additions and 763 deletions
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220
crates/environ/fuzz/fuzz_targets/fact-valid-module.rs
View File

@@ -10,9 +10,9 @@
#![no_main]
use arbitrary::Arbitrary;
use component_fuzz_util::Type as ValType;
use component_fuzz_util::TestCase;
use libfuzzer_sys::fuzz_target;
use wasmparser::{Validator, WasmFeatures};
use wasmparser::{Parser, Payload, Validator, WasmFeatures};
use wasmtime_environ::component::*;
use wasmtime_environ::fact::Module;
@@ -24,25 +24,10 @@ struct GenAdapterModule {
#[derive(Arbitrary, Debug)]
struct GenAdapter {
ty: FuncType,
post_return: bool,
lift_memory64: bool,
lower_memory64: bool,
lift_encoding: GenStringEncoding,
lower_encoding: GenStringEncoding,
}
#[derive(Arbitrary, Debug)]
struct FuncType {
params: Vec<ValType>,
result: ValType,
}
#[derive(Copy, Clone, Arbitrary, Debug)]
enum GenStringEncoding {
Utf8,
Utf16,
CompactUtf16,
test: TestCase,
}
fuzz_target!(|module: GenAdapterModule| {
@@ -90,47 +75,74 @@ fn target(module: GenAdapterModule) {
let mut adapters = Vec::new();
for adapter in module.adapters.iter() {
let mut params = Vec::new();
for param in adapter.ty.params.iter() {
params.push((None, intern(&mut types, param)));
let wat_decls = adapter.test.declarations();
let wat = format!(
"(component
{types}
(type (func {params} {result}))
)",
types = wat_decls.types,
params = wat_decls.params,
result = wat_decls.result,
);
let wasm = wat::parse_str(&wat).unwrap();
let mut validator = Validator::new_with_features(WasmFeatures {
component_model: true,
..Default::default()
});
types.push_type_scope();
for payload in Parser::new(0).parse_all(&wasm) {
let payload = payload.unwrap();
validator.payload(&payload).unwrap();
let section = match payload {
Payload::ComponentTypeSection(s) => s,
_ => continue,
};
for ty in section {
let ty = types.intern_component_type(&ty.unwrap()).unwrap();
types.push_component_typedef(ty);
let ty = match ty {
TypeDef::ComponentFunc(ty) => ty,
_ => continue,
};
adapters.push(Adapter {
lift_ty: ty,
lower_ty: ty,
lower_options: AdapterOptions {
instance: RuntimeComponentInstanceIndex::from_u32(0),
string_encoding: convert_encoding(adapter.test.encoding1),
memory64: adapter.lower_memory64,
// Pessimistically assume that memory/realloc are going to be
// required for this trampoline and provide it. Avoids doing
// calculations to figure out whether they're necessary and
// simplifies the fuzzer here without reducing coverage within FACT
// itself.
memory: Some(dummy_memory(adapter.lower_memory64)),
realloc: Some(dummy_def()),
// Lowering never allows `post-return`
post_return: None,
},
lift_options: AdapterOptions {
instance: RuntimeComponentInstanceIndex::from_u32(1),
string_encoding: convert_encoding(adapter.test.encoding2),
memory64: adapter.lift_memory64,
memory: Some(dummy_memory(adapter.lift_memory64)),
realloc: Some(dummy_def()),
post_return: if adapter.post_return {
Some(dummy_def())
} else {
None
},
},
func: dummy_def(),
});
}
}
let result = intern(&mut types, &adapter.ty.result);
let signature = types.add_func_type(TypeFunc {
params: params.into(),
result,
});
adapters.push(Adapter {
lift_ty: signature,
lower_ty: signature,
lower_options: AdapterOptions {
instance: RuntimeComponentInstanceIndex::from_u32(0),
string_encoding: adapter.lower_encoding.into(),
memory64: adapter.lower_memory64,
// Pessimistically assume that memory/realloc are going to be
// required for this trampoline and provide it. Avoids doing
// calculations to figure out whether they're necessary and
// simplifies the fuzzer here without reducing coverage within FACT
// itself.
memory: Some(dummy_memory(adapter.lower_memory64)),
realloc: Some(dummy_def()),
// Lowering never allows `post-return`
post_return: None,
},
lift_options: AdapterOptions {
instance: RuntimeComponentInstanceIndex::from_u32(1),
string_encoding: adapter.lift_encoding.into(),
memory64: adapter.lift_memory64,
memory: Some(dummy_memory(adapter.lift_memory64)),
realloc: Some(dummy_def()),
post_return: if adapter.post_return {
Some(dummy_def())
} else {
None
},
},
func: dummy_def(),
});
types.pop_type_scope();
}
let types = types.finish();
let mut fact_module = Module::new(&types, module.debug);
for (i, adapter) in adapters.iter().enumerate() {
@@ -161,94 +173,10 @@ fn target(module: GenAdapterModule) {
panic!()
}
fn intern(types: &mut ComponentTypesBuilder, ty: &ValType) -> InterfaceType {
match ty {
ValType::Unit => InterfaceType::Unit,
ValType::Bool => InterfaceType::Bool,
ValType::U8 => InterfaceType::U8,
ValType::S8 => InterfaceType::S8,
ValType::U16 => InterfaceType::U16,
ValType::S16 => InterfaceType::S16,
ValType::U32 => InterfaceType::U32,
ValType::S32 => InterfaceType::S32,
ValType::U64 => InterfaceType::U64,
ValType::S64 => InterfaceType::S64,
ValType::Float32 => InterfaceType::Float32,
ValType::Float64 => InterfaceType::Float64,
ValType::Char => InterfaceType::Char,
ValType::String => InterfaceType::String,
ValType::List(ty) => {
let ty = intern(types, ty);
InterfaceType::List(types.add_interface_type(ty))
}
ValType::Record(tys) => {
let ty = TypeRecord {
fields: tys
.iter()
.enumerate()
.map(|(i, ty)| RecordField {
name: format!("f{i}"),
ty: intern(types, ty),
})
.collect(),
};
InterfaceType::Record(types.add_record_type(ty))
}
ValType::Flags(size) => {
let ty = TypeFlags {
names: (0..size.as_usize()).map(|i| format!("f{i}")).collect(),
};
InterfaceType::Flags(types.add_flags_type(ty))
}
ValType::Tuple(tys) => {
let ty = TypeTuple {
types: tys.iter().map(|ty| intern(types, ty)).collect(),
};
InterfaceType::Tuple(types.add_tuple_type(ty))
}
ValType::Variant(cases) => {
let ty = TypeVariant {
cases: cases
.iter()
.enumerate()
.map(|(i, ty)| VariantCase {
name: format!("c{i}"),
ty: intern(types, ty),
})
.collect(),
};
InterfaceType::Variant(types.add_variant_type(ty))
}
ValType::Union(tys) => {
let ty = TypeUnion {
types: tys.iter().map(|ty| intern(types, ty)).collect(),
};
InterfaceType::Union(types.add_union_type(ty))
}
ValType::Enum(size) => {
let ty = TypeEnum {
names: (0..size.as_usize()).map(|i| format!("c{i}")).collect(),
};
InterfaceType::Enum(types.add_enum_type(ty))
}
ValType::Option(ty) => {
let ty = intern(types, ty);
InterfaceType::Option(types.add_interface_type(ty))
}
ValType::Expected { ok, err } => {
let ok = intern(types, ok);
let err = intern(types, err);
InterfaceType::Expected(types.add_expected_type(TypeExpected { ok, err }))
}
}
}
impl From<GenStringEncoding> for StringEncoding {
fn from(gen: GenStringEncoding) -> StringEncoding {
match gen {
GenStringEncoding::Utf8 => StringEncoding::Utf8,
GenStringEncoding::Utf16 => StringEncoding::Utf16,
GenStringEncoding::CompactUtf16 => StringEncoding::CompactUtf16,
}
fn convert_encoding(encoding: component_fuzz_util::StringEncoding) -> StringEncoding {
match encoding {
component_fuzz_util::StringEncoding::Utf8 => StringEncoding::Utf8,
component_fuzz_util::StringEncoding::Utf16 => StringEncoding::Utf16,
component_fuzz_util::StringEncoding::Latin1OrUtf16 => StringEncoding::CompactUtf16,
}
}