ZCC

ZJU standard C Compiler

Code Organization

• Lex and Yas related codes are in the folder yyparse.
• Symbol table and Type check related codes are in the folder symbol.
• Generating machine code related codes are in the folder generation.
• Treating Special variables related codes are in the folder public.
• Optimization codes are stored separately in each folder.

Parsing Tree Sample：

declaration
    declaration_specifiers
        storage_class_specifier
            typedef
        declaration_specifiers
            type_specifier
                struct_or_union_specifier
                    struct_or_union
                        struct
                    {
                    struct_declaration_list
                        struct_declaration_list
                            struct_declaration
                                specifier_qualifier_list
                                    type_specifier
                                        int
                                struct_declarator_list
                                    struct_declarator
                                        declarator
                                            direct_declarator
                                                a
                                ;
                        struct_declaration
                            specifier_qualifier_list
                                type_specifier
                                    double
                            struct_declarator_list
                                struct_declarator
                                    declarator
                                        direct_declarator
                                            c
                            ;
                    }
    init_declarator_list
        init_declarator
            declarator
                direct_declarator
                    mytype
    ;

Code Generation

Miscellaneous

Call functions in self.tools to translate.

Detailed comments and examples can be found in generation.generate.

Basic X86 supports

• Calculation: add, sub, mul, div.
• Logic: and, or, not.
• Jump: jmp, je, jg, jl.
• Shift: sal, sar.
• Function: call, ret.
• Stack: push, pop.
• Float number operation: fld, fstp, fadd, fsub, fmul, fdiv.
• Global/Static variables, Constant float number, String

Code Optimization

The optimization types supported

http://www.compileroptimizations.com/index.html

Constant propagation

http://people.eecs.berkeley.edu/~bodik/cs264/lectures/4-chaotic-notes.pdf