Function optimise_module

src/optimise1.rs:331–359

(module: Module)

        format!("Optimizing module: {}", module.name)
    );
    for (name, func) in old_funcs {
        breadcrumbs::log!(
            breadcrumbs::LogLevel::Info,
            "optimisation",
            format!("Optimizing function: {}", name)
        );
        // Pass data_types needed for analysis/transformation
        let new_func = optimise_function(func, &module.data_types);
        new_funcs.insert(name, new_func);
    }

    // Rust emits tiny generic helpers such as `needs_drop::<T>` as ordinary
    // functions even when their result is a compile-time constant. Fold calls
    // to side-effect-free constant-returning functions before the caller's
    // final optimisation pass. This lets constant branches and the pointer
    // temporaries contained exclusively in their dead arms disappear before
    // JVM lowering.
    let constant_returns = new_funcs
        .iter()
        .filter_map(|(key, function)| {
            simple_constant_return(function).map(|constant| (key.clone(), constant))
        })
        .collect::<HashMap<_, _>>();
    for function in new_funcs.values_mut() {
        if fold_constant_static_calls(function, &constant_returns) {
            optimise_function_in_place(function, &module.data_types);
        }
    }

    breadcrumbs::log!(
        breadcrumbs::LogLevel::Info,
        "optimisation",