Linker.java 文件源码

/**
 * Returns an ExecutableCode that can then be run by the processor. If the given code contains
 * data section, linker will only generate memory addresses. Without loading process, referenced
 * data will be unpredictable.
 *
 * @param code The code that will be linked.
 *
 * @return The executable code.
 *
 * @throws LabelError If an undefined label used or duplicate labels exist.
 * @see Loader#load(Linker.ExecutableCode)
 */
public ExecutableCode link(String code) throws LabelError {
    definedBranches.clear();
    definedData.clear();
    addressBook.clear();
    secondPass = false;
    this.code = parseCode(code);
    AssemblerLexer lexer = new AssemblerLexer(CharStreams.fromString(code));
    CommonTokenStream tokens = new CommonTokenStream(lexer);
    AssemblerParser parser = new AssemblerParser(tokens);
    AssemblerParser.ProgContext program = parser.prog();
    visit(program);
    secondPass = true;
    visit(program);
    List<Data> temp = new ArrayList<>(definedData.size());
    definedData.forEach((label, data) -> {
        temp.add(data);
    });
    return new ExecutableCode(this.code, temp);
}