feat: initial support for the webassembly gc proposal (#50)

Signed-off-by: Henry <mail@henrygressmann.de>

Author: explodingcamera

CHANGELOG.md

@@ -10,12 +10,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - Added support for the WebAssembly function-references proposal
+- Added support for the WebAssembly garbage-collection proposal
 - Added `WasmValue::ty` and `WasmValue::matches_type`
 - Added a `validate` feature to `tinywasm` and `tinywasm-parser` (enabled by default) to optionally skip wasmparser validation for faster parsing of trusted modules.
 
 ### Changed
 
-- Function types are now stored separately and resolved through `Function::ty(&Store)`.
+- Module types now use one dense recursive type space, while function types are resolved through `Function::ty(&Store)`.
 
 ### Fixed
 

Cargo.lock

@@ -21,12 +21,10 @@ categories = ["compilers", "embedded", "no-std", "virtualization", "wasm"]
 
 [workspace.dependencies]
 tinywasm = { path = "crates/tinywasm", version = "0.11.0-pre.0", default-features = false }
-tinywasm-cli = { path = "crates/cli", version = "0.11.0-pre.0", default-features = false }
 tinywasm-parser = { path = "crates/parser", version = "0.11.0-pre.0", default-features = false }
 tinywasm-types = { path = "crates/types", version = "0.11.0-pre.0", default-features = false }
 
 eyre = "0.6"
-indexmap = "2.14"
 log = "0.4"
 owo-colors = { version = "4.3" }
 pretty_env_logger = "0.5"

Cargo.toml

@@ -57,7 +57,7 @@ See the [examples](./examples) directory and [documentation](https://docs.rs/tin
 
 With default features disabled, `tinywasm` depends only on `core`, `alloc`, and `libm`[^libm], making it usable in `no_std + alloc` environments.
 
-Use `Engine` and `engine::Config` when you need non-default runtime settings such as fuel accounting, stack sizing, memory backend selection, or trap-on-OOM behavior.
+Use `Engine` and `engine::Config` when you need non-default runtime settings such as fuel accounting, stack sizing, memory backend selection, the GC collection threshold, or trap-on-OOM behavior.
 
 [^libm]: [rust-lang/rust#137578](https://github.com/rust-lang/rust/issues/137578) — tracking issue for floating-point math support in `no_std`.
 
@@ -75,27 +75,31 @@ The internal `twasm` bytecode format is not currently validated as an untrusted
 
 ## Supported Proposals
 
-| Proposal                                                                                                                                | Status | `tinywasm` Version |
-| --------------------------------------------------------------------------------------------------------------------------------------- | ------ | ------------------ |
-| [**Multi-value**](https://github.com/WebAssembly/spec/blob/master/proposals/multi-value/Overview.md)                                    | 🟢     | 0.2.0              |
-| [**Mutable Globals**](https://github.com/WebAssembly/mutable-global/blob/master/proposals/mutable-global/Overview.md)                   | 🟢     | 0.2.0              |
-| [**Non-trapping float-to-int Conversion**](https://github.com/WebAssembly/nontrapping-float-to-int-conversions)                         | 🟢     | 0.2.0              |
-| [**Sign-extension operators**](https://github.com/WebAssembly/sign-extension-ops)                                                       | 🟢     | 0.2.0              |
-| [**Bulk Memory Operations**](https://github.com/WebAssembly/spec/blob/master/proposals/bulk-memory-operations/Overview.md)              | 🟢     | 0.4.0              |
-| [**Reference Types**](https://github.com/WebAssembly/reference-types/blob/master/proposals/reference-types/Overview.md)                 | 🟢     | 0.7.0              |
-| [**Multi-memory**](https://github.com/WebAssembly/multi-memory/blob/master/proposals/multi-memory/Overview.md)                          | 🟢     | 0.8.0              |
-| [**Custom Page Sizes**](https://github.com/WebAssembly/custom-page-sizes/blob/main/proposals/custom-page-sizes/Overview.md)             | 🟢     | 0.9.0              |
-| [**Extended Const**](https://github.com/WebAssembly/extended-const/blob/main/proposals/extended-const/Overview.md)                      | 🟢     | 0.9.0              |
-| [**Fixed-Width SIMD**](https://github.com/WebAssembly/simd/blob/main/proposals/simd/Overview.md)                                        | 🟢     | 0.9.0              |
-| [**Memory64**](https://github.com/WebAssembly/memory64/blob/master/proposals/memory64/Overview.md)                                      | 🟢     | 0.9.0              |
-| [**Tail Call**](https://github.com/WebAssembly/tail-call/blob/main/proposals/tail-call/Overview.md)                                     | 🟢     | 0.9.0              |
-| [**Relaxed SIMD**](https://github.com/WebAssembly/relaxed-simd/blob/main/proposals/relaxed-simd/Overview.md)                            | 🟢     | 0.9.0              |
-| [**Wide Arithmetic**](https://github.com/WebAssembly/wide-arithmetic/blob/main/proposals/wide-arithmetic/Overview.md)                   | 🟢     | 0.9.0              |
-| [**Typed Function References**](https://github.com/WebAssembly/function-references/blob/main/proposals/function-references/Overview.md) | 🚧     | `next`             |
-| [**Exception Handling**](https://github.com/WebAssembly/exception-handling/blob/main/proposals/exception-handling/Exceptions.md)        | 🌑     | -                  |
-| [**Garbage Collection**](https://github.com/WebAssembly/gc/blob/main/proposals/gc/Overview.md)                                          | 🌑     | -                  |
-| [**Stack Switching**](https://github.com/WebAssembly/stack-switching/blob/main/proposals/stack-switching/Explainer.md)                  | 🌑     | -                  |
-| [**Threads**](https://github.com/WebAssembly/threads/blob/main-legacy/proposals/threads/Overview.md)                                    | 🌑     | -                  |
+TinyWasm targets non-JavaScript core proposals through [phase 3](https://github.com/WebAssembly/proposals). JavaScript integrations and optional embedding or tooling APIs are not included here.
+
+| Proposal                                                                                                         | Status | `tinywasm` Version |
+| ---------------------------------------------------------------------------------------------------------------- | ------ | ------------------ |
+| [**Import/Export of Mutable Globals**](https://github.com/WebAssembly/mutable-global)                            | 🟢     | 0.2.0              |
+| [**Multi-value**](https://github.com/WebAssembly/multi-value)                                                    | 🟢     | 0.2.0              |
+| [**Non-trapping Float-to-int Conversions**](https://github.com/WebAssembly/nontrapping-float-to-int-conversions) | 🟢     | 0.2.0              |
+| [**Sign-extension Operators**](https://github.com/WebAssembly/sign-extension-ops)                                | 🟢     | 0.2.0              |
+| [**Bulk Memory Operations**](https://github.com/WebAssembly/bulk-memory-operations)                              | 🟢     | 0.4.0              |
+| [**Reference Types**](https://github.com/WebAssembly/reference-types)                                            | 🟢     | 0.7.0              |
+| [**Fixed-width SIMD**](https://github.com/WebAssembly/simd)                                                      | 🟢     | 0.9.0              |
+| [**Tail Calls**](https://github.com/WebAssembly/tail-call)                                                       | 🟢     | 0.9.0              |
+| [**Extended Constant Expressions**](https://github.com/WebAssembly/extended-const)                               | 🟢     | 0.9.0              |
+| [**Multiple Memories**](https://github.com/WebAssembly/multi-memory)                                             | 🟢     | 0.8.0              |
+| [**Relaxed SIMD**](https://github.com/WebAssembly/relaxed-simd)                                                  | 🟢     | 0.9.0              |
+| [**Custom Annotation Syntax**](https://github.com/WebAssembly/annotations)                                       | 🟢     | 0.8.0              |
+| [**Memory64**](https://github.com/WebAssembly/memory64)                                                          | 🟢     | 0.9.0              |
+| [**Wide Arithmetic**](https://github.com/WebAssembly/wide-arithmetic)                                            | 🟢     | 0.9.0              |
+| [**Custom Page Sizes**](https://github.com/WebAssembly/custom-page-sizes)                                        | 🟢     | 0.9.0              |
+| [**Typed Function References**](https://github.com/WebAssembly/function-references)                              | 🟢     | `next`             |
+| [**Garbage Collection**](https://github.com/WebAssembly/gc)                                                      | 🟢     | `next`             |
+| [**Exception Handling**](https://github.com/WebAssembly/exception-handling)                                      | 🌑     | -                  |
+| [**Stack Switching**](https://github.com/WebAssembly/stack-switching)                                            | 🌑     | -                  |
+| [**Compact Import Section**](https://github.com/WebAssembly/compact-import-section)                              | 🌑     | -                  |
+| [**Threads**](https://github.com/WebAssembly/threads)                                                            | 🌑     | -                  |
 
 **Legend**\
 🌑 -- not available\

README.md

@@ -7,7 +7,10 @@ use std::time::Duration;
 
 use eyre::{Context, Result, bail, eyre};
 use log::{debug, error};
-use tinywasm::types::{ExternRef, FuncRef, MemoryType, RefType, RefValue, TableType, WasmType, WasmValue};
+use tinywasm::types::{
+    AbstractHeapType as TinyAbstractHeapType, AnyRef, ExternRef, FuncRef, MemoryType, RefType, RefValue, TableType,
+    WasmType, WasmValue,
+};
 use tinywasm::{ExecProgress, Global, HostFunction, Imports, Memory, Module, ModuleInstance, Store, Table};
 use wast::{QuoteWat, core::AbstractHeapType};
 
@@ -459,7 +462,7 @@ impl WastRunner {
                             let expected = expected_alternatives
                                 .iter()
                                 .filter_map(|alts| alts.first())
-                                .find(|exp| exp.matches(&module_global));
+                                .find(|exp| exp.matches(&module_global, &store));
                             if expected.is_none() {
                                 test_group.add_result(
                                     &format!("AssertReturn(unsupported-{i})"),
@@ -508,7 +511,10 @@ impl WastRunner {
                         }
                         if expected_alternatives.iter().any(|expected| {
                             expected.len() == outcomes.len()
-                                && outcomes.iter().zip(expected.iter()).all(|(outcome, exp)| exp.matches(outcome))
+                                && outcomes
+                                    .iter()
+                                    .zip(expected.iter())
+                                    .all(|(outcome, exp)| exp.matches(outcome, &store))
                         }) {
                             Ok(())
                         } else {
@@ -755,16 +761,18 @@ fn wastarg2tinywasmvalue(arg: wast::WastArg) -> Result<WasmValue> {
         I32(i) => WasmValue::I32(i),
         I64(i) => WasmValue::I64(i),
         V128(i) => WasmValue::V128(i.to_le_bytes()),
-        RefExtern(v) => ExternRef::new(v).into(),
+        RefExtern(v) => ExternRef::try_new(v).ok_or_else(|| eyre!("external reference address is too large"))?.into(),
         RefNull(t) => match t {
             wast::core::HeapType::Abstract { shared: false, ty: AbstractHeapType::Func } => RefValue::Null.into(),
-            wast::core::HeapType::Abstract { shared: false, ty: AbstractHeapType::Extern } => RefValue::Null.into(),
+            wast::core::HeapType::Abstract { shared: false, ty: AbstractHeapType::Extern | AbstractHeapType::Any } => {
+                RefValue::Null.into()
+            }
             _ => {
                 bail!("unsupported arg type: refnull: {:?}", t);
             }
         },
-        RefHost(_) => {
-            bail!("unsupported arg type: RefHost");
+        RefHost(value) => {
+            RefValue::Any(AnyRef::from_host(value).ok_or_else(|| eyre!("host reference address is too large"))?).into()
         }
     })
 }
@@ -791,15 +799,29 @@ enum ExpectedValue {
     RefNull,
     RefFunc,
     RefExtern,
+    RefAny,
+    RefEq,
+    RefI31,
+    RefStruct,
+    RefArray,
 }
 
 impl ExpectedValue {
-    fn matches(&self, value: &WasmValue) -> bool {
+    fn matches(&self, value: &WasmValue, store: &Store) -> bool {
         match self {
             Self::Exact(expected) => value.eq_loose(expected),
             Self::RefNull => matches!(value, WasmValue::Ref(RefValue::Null)),
             Self::RefFunc => matches!(value, WasmValue::Ref(RefValue::Func(_))),
             Self::RefExtern => matches!(value, WasmValue::Ref(RefValue::Extern(_))),
+            Self::RefAny => matches!(value, WasmValue::Ref(RefValue::Any(_))),
+            Self::RefEq => {
+                store.value_matches_type(*value, WasmType::Ref(RefType::new_abstract(false, TinyAbstractHeapType::Eq)))
+            }
+            Self::RefI31 => matches!(value, WasmValue::Ref(RefValue::Any(value)) if value.as_i31().is_some()),
+            Self::RefStruct => store
+                .value_matches_type(*value, WasmType::Ref(RefType::new_abstract(false, TinyAbstractHeapType::Struct))),
+            Self::RefArray => store
+                .value_matches_type(*value, WasmType::Ref(RefType::new_abstract(false, TinyAbstractHeapType::Array))),
         }
     }
 }
@@ -817,21 +839,34 @@ fn wastret2tinywasmvalues(ret: wast::WastRet) -> Result<Vec<ExpectedValue>> {
 }
 
 fn wastretcore2tinywasmvalue(ret: wast::core::WastRetCore) -> Result<ExpectedValue> {
-    use wast::core::WastRetCore::{F32, F64, I32, I64, RefExtern, RefFunc, RefNull, V128};
+    use wast::core::WastRetCore::{
+        F32, F64, I32, I64, RefAny, RefArray, RefEq, RefExtern, RefFunc, RefHost, RefI31, RefI31Shared, RefNull,
+        RefStruct, V128,
+    };
     Ok(match ret {
         F32(f) => ExpectedValue::Exact(nanpattern2tinywasmvalue(f)?),
         F64(f) => ExpectedValue::Exact(nanpattern2tinywasmvalue(f)?),
         I32(i) => ExpectedValue::Exact(WasmValue::I32(i)),
         I64(i) => ExpectedValue::Exact(WasmValue::I64(i)),
         V128(i) => ExpectedValue::Exact(WasmValue::V128(wast_v128_to_bytes(i))),
         RefNull(_) => ExpectedValue::RefNull,
-        RefExtern(Some(v)) => ExpectedValue::Exact(ExternRef::new(v).into()),
+        RefExtern(Some(v)) => ExpectedValue::Exact(
+            ExternRef::try_new(v).ok_or_else(|| eyre!("external reference address is too large"))?.into(),
+        ),
         RefExtern(None) => ExpectedValue::RefExtern,
         RefFunc(Some(wast::token::Index::Num(n, _))) => ExpectedValue::Exact(FuncRef::new(n).into()),
         RefFunc(None) => ExpectedValue::RefFunc,
         RefFunc(v) => {
             bail!("unsupported arg type: reffunc: {:?}", v);
         }
+        RefAny => ExpectedValue::RefAny,
+        RefEq => ExpectedValue::RefEq,
+        RefI31 | RefI31Shared => ExpectedValue::RefI31,
+        RefStruct => ExpectedValue::RefStruct,
+        RefArray => ExpectedValue::RefArray,
+        RefHost(value) => ExpectedValue::Exact(
+            RefValue::Any(AnyRef::from_host(value).ok_or_else(|| eyre!("host reference address is too large"))?).into(),
+        ),
         a => {
             bail!("unsupported arg type {:?}", a);
         }