implement fuzzing for component types

This addresses bytecodealliance#4307.

For the static API we generate 100 arbitrary test cases at build time, each of
which includes 0-5 parameter types, a result type, and a WAT fragment containing
an imported function and an exported function.  The exported function calls the
imported function, which is implemented by the host.  At runtime, the fuzz test
selects a test case at random and feeds it zero or more sets of arbitrary
parameters and results, checking that values which flow host-to-guest and
guest-to-host make the transition unchanged.

The fuzz test for the dynamic API follows a similar pattern, the only difference
being that test cases are generated at runtime.

Signed-off-by: Joel Dice <[email protected]>

fix build error and type name tracking

This fixes two issues:

- build.rs was failing to build when the component_model feature was not enabled

- Name assignments for types in component_types.rs were not being tracked
  properly because structurally identical types were being considered equal to
  each other.

Signed-off-by: Joel Dice <[email protected]>

Cargo.toml

@@ -60,6 +60,7 @@ wat = "1.0.47"
 once_cell = "1.9.0"
 rayon = "1.5.0"
 component-macro-test = { path = "crates/misc/component-macro-test" }
+component-test-util = { path = "crates/misc/component-test-util" }
 
 [target.'cfg(windows)'.dev-dependencies]
 windows-sys = { version = "0.36.0", features = ["Win32_System_Memory"] }

build.rs

@@ -43,7 +43,7 @@ fn main() -> anyhow::Result<()> {
             } else {
                 println!(
                     "cargo:warning=The spec testsuite is disabled. To enable, run `git submodule \
-                 update --remote`."
+                     update --remote`."
                 );
             }
             Ok(())

crates/fuzzing/Cargo.toml

@@ -10,14 +10,18 @@ license = "Apache-2.0 WITH LLVM-exception"
 [dependencies]
 anyhow = "1.0.22"
 arbitrary = { version = "1.1.0", features = ["derive"] }
+component-test-util = { path = "../misc/component-test-util" }
 env_logger = "0.9.0"
 log = "0.4.8"
+proc-macro2 = "1.0"
+quote = "1.0"
 rayon = "1.2.1"
 target-lexicon = "0.12.3"
 tempfile = "3.3.0"
 wasmparser = "0.88.0"
 wasmprinter = "0.2.38"
 wasmtime = { path = "../wasmtime" }
+wasmtime-component-util = { path = "../component-util" }
 wasmtime-wast = { path = "../wast" }
 wasm-encoder = "0.15.0"
 wasm-smith = "0.11.3"
@@ -43,4 +47,6 @@ rand = { version = "0.8.0", features = ["small_rng"] }
 wasm-spec-interpreter = { path = "./wasm-spec-interpreter", optional = true, features = ['build-libinterpret'] }
 
 [features]
+default = ['fuzz-spec-interpreter']
 fuzz-spec-interpreter = ['wasm-spec-interpreter']
+component-model = ['wasmtime/component-model']

crates/fuzzing/src/generators.rs

@@ -20,6 +20,9 @@ mod spec_test;
 mod stacks;
 pub mod table_ops;
 
+#[cfg(feature = "component-model")]
+pub mod component_types;
+
 pub use codegen_settings::CodegenSettings;
 pub use config::{Config, WasmtimeConfig};
 pub use instance_allocation_strategy::InstanceAllocationStrategy;