Function optimise_function

src/optimise1.rs:252–329

(
    mut function: Function,
    data_types: &HashMap<String, DataType>,
)

                function.name
            )
        );
        return;
    }
    breadcrumbs::log!(
        breadcrumbs::LogLevel::Info,
        "optimisation",
        format!("Optimizing function: {}", function.name)
    );

    // 0. Run needed reorganisation passes
    convert_labels_to_basic_blocks_in_function(function);
    eliminate_duplicate_basic_blocks(function);

    // 1. Build Initial CFG
    let cfg = build_cfg(&mut function.body);
    if cfg.is_empty() {
        breadcrumbs::log!(
            breadcrumbs::LogLevel::Warn,
            "optimisation",
            format!(
                "Warning: CFG construction failed for non-empty function {}",
                function.name
            )
        );
        return;
    }

    // 2. Perform Dataflow Analysis (Constant Propagation)
    // Ensure entry point exists in CFG before analysis
    if !cfg.contains_key(&function.body.entry) && !cfg.is_empty() {
        breadcrumbs::log!(
            breadcrumbs::LogLevel::Error,
            "optimisation",
            format!(
                "ERROR: Entry block '{}' not found in CFG for function {}. Skipping optimization.",
                function.body.entry, function.name
            )
        );
        // This might happen if the entry block itself has no instructions or references invalid blocks.
        function.body.basic_blocks = cfg
            .into_iter()
            .map(|(label, info)| (label, info.original_block))
            .collect();
        return;
    }
    let analysis_result = analyze_constant_propagation(&function.body.entry, &cfg);

    // 3. Transform & Perform Dead Code Elimination
    transform_function(function, &cfg, &analysis_result, data_types);

    // 4. Clean up simple copies introduced by lowering and constant/algebraic rewrites.
    propagate_copies_and_eliminate_dead_moves(function);

    // 5. Eliminate duplicate basic blocks (re-pass-through after transformation)
    eliminate_duplicate_basic_blocks(function);

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