Change spectest fuzzing to throw out some fuzz inputs

crates/fuzzing/src/generators/config.rs

@@ -97,31 +97,45 @@ impl Config {
  self.module_config.generate(input, default_fuel)
  }
 
- /// Indicates that this configuration should be spec-test-compliant,
- /// disabling various features the spec tests assert are disabled.
- pub fn set_spectest_compliant(&mut self) {
- let config = &mut self.module_config.config;
- config.memory64_enabled = false;
- config.bulk_memory_enabled = true;
- config.reference_types_enabled = true;
- config.multi_value_enabled = true;
- config.simd_enabled = true;
- config.threads_enabled = false;
- config.max_memories = 1;
- config.max_tables = 5;
+ /// Tests whether this configuration is capable of running all spec tests.
+ pub fn is_spectest_compliant(&self) -> bool {
+ let config = &self.module_config.config;
 
- if let InstanceAllocationStrategy::Pooling(pooling) = &mut self.wasmtime.strategy {
- // Configure the lower bound of a number of limits to what's
- // required to actually run the spec tests. Fuzz-generated inputs
- // may have limits less than these thresholds which would cause the
- // spec tests to fail which isn't particularly interesting.
- pooling.instance_memories = 1;
- pooling.instance_tables = pooling.instance_tables.max(5);
- pooling.instance_table_elements = pooling.instance_table_elements.max(1_000);
- pooling.instance_memory_pages = pooling.instance_memory_pages.max(900);
- pooling.instance_count = pooling.instance_count.max(500);
- pooling.instance_size = pooling.instance_size.max(64 * 1024);
+ // Check for wasm features that must be disabled to run spec tests
+ if config.memory64_enabled || config.threads_enabled {
+ return false;
+ }
+
+ // Check for wasm features that must be enabled to run spec tests
+ if !config.bulk_memory_enabled
+ || !config.reference_types_enabled
+ || !config.multi_value_enabled
+ || !config.simd_enabled
+ {
+ return false;
+ }
+
+ // Make sure the runtime limits allow for the instantiation of all spec
+ // tests.
+ if config.max_memories < 1 || config.max_tables < 5 {
+ return false;
  }
+
+ if let InstanceAllocationStrategy::Pooling(pooling) = &self.wasmtime.strategy {
+ // Check to see if any item limit is less than the required
+ // threshold to execute the spec tests.
+ if pooling.instance_memories < 1
+ || pooling.instance_tables < 5
+ || pooling.instance_table_elements < 1_000
+ || pooling.instance_memory_pages < 900
+ || pooling.instance_count < 500
+ || pooling.instance_size < 64 * 1024
+ {
+ return false;
+ }
+ }
+
+ true
  }
 
  /// Converts this to a `wasmtime::Config` object

crates/fuzzing/src/oracles.rs

@@ -501,9 +501,11 @@ pub fn make_api_calls(api: generators::api::ApiCalls) {
 /// Executes the wast `test` spectest with the `config` specified.
 ///
 /// Ensures that spec tests pass regardless of the `Config`.
-pub fn spectest(mut fuzz_config: generators::Config, test: generators::SpecTest) {
+pub fn spectest(fuzz_config: generators::Config, test: generators::SpecTest) {
  crate::init_fuzzing();
- fuzz_config.set_spectest_compliant();
+ if !fuzz_config.is_spectest_compliant() {
+ return;
+ }
  log::debug!("running {:?}", test.file);
  let mut wast_context = WastContext::new(fuzz_config.to_store());
  wast_context.register_spectest(false).unwrap();