Function compile_module

crates/fuzzing/src/oracles.rs:325–377

(
    engine: &Engine,
    bytes: &[u8],
    known_valid: KnownValid,
    config: &generators::Config,
)

}

fn compile_module(
    engine: &Engine,
    bytes: &[u8],
    known_valid: KnownValid,
    config: &generators::Config,
) -> Option<Module> {
    log_wasm(bytes);

    match config.compile(engine, bytes) {
        Ok(module) => Some(module),
        Err(_) if known_valid == KnownValid::No => None,
        Err(e) => {
            if let generators::InstanceAllocationStrategy::Pooling(c) = &config.wasmtime.strategy {
                // When using the pooling allocator, accept failures to compile
                // when arbitrary table element limits have been exceeded as
                // there is currently no way to constrain the generated module
                // table types.
                let string = format!("{e:?}");
                if string.contains("minimum element size") {
                    return None;
                }

                // Allow modules-failing-to-compile which exceed the requested
                // size for each instance. This is something that is difficult
                // to control and ensure it always succeeds, so we simply have a
                // "random" instance size limit and if a module doesn't fit we
                // move on to the next fuzz input.
                if string.contains("instance allocation for this module requires") {
                    return None;
                }

                // If the pooling allocator is more restrictive on the number of
                // tables and memories than we allowed wasm-smith to generate
                // then allow compilation errors along those lines.
                if c.max_tables_per_module < (config.module_config.config.max_tables as u32)
                    && string.contains("defined tables count")
                    && string.contains("exceeds the per-instance limit")
                {
                    return None;
                }

                if c.max_memories_per_module < (config.module_config.config.max_memories as u32)
                    && string.contains("defined memories count")
                    && string.contains("exceeds the per-instance limit")
                {
                    return None;
                }
            }

            panic!("failed to compile module: {e:?}");
        }
    }
}

/// Create a Wasmtime [`Instance`] from a [`Module`] and fill in all imports
/// with dummy values (e.g., zeroed values, immediately-trapping functions).