#ifndef __CODE_H
#define __CODE_H

#include "thunk.h"

enum CodeType {
    CT_VAR, CT_VAR_STRICT, CT_APP, CT_APP_DYN, CT_SELECT, CT_IF, CT_THUNK
};

struct Code {
    CodeType type : 3;
    unsigned int nr_args : 5;       // used in AppEntry
    unsigned int nr_cases : 5;      // used in SelectEntry
    unsigned int strict : 1;        // used in VarEntry
};

struct ThunkEntry {
    struct Code base;
    struct Thunk thunk;
};

struct VarEntry {
    struct Code base;
    int index; // index on the stack
};

struct AppEntry {
    struct Code base;
    union {
        struct VarEntry var;
        struct Desc* f;
    };
    struct Code* args[];
};

#define SC_CONS			1
#define SC_LIT			2
#define SC_DEFAULT		3

struct SelectCaseEntry {
    int type;
    struct Code* body;

    union {
        struct ADTEntry* cons;
        struct ThunkEntry* lit;
    };
};

struct SelectEntry {
    struct Code base;
    struct Code* expr;
    struct SelectCaseEntry cases[];
};

struct IfEntry {
    struct Code base;
    struct Code* cond;
    struct Code* texpr;
    struct Code* fexpr;
};

void exec(Code* expr, int frame_ptr, int root_frame_ptr, int root_frame_ptr_b);
struct Thunk* eval(Thunk* thunk);

#endif // __CODE_H