thesis-lisp/vm/include/vmval.h

#pragma once
#include <stddef.h>
#include <stdint.h>
#include <assert.h>
#include <stdio.h>

#include "vmstring.h"
#include "vmstate.h"

enum vm_type {
    VT_CONS,
    VT_STRING,
    VT_FUNC,
    VT_CFUNC,
};

struct vm_value {
    enum vm_type type;
    size_t refcount;
    union {
        struct {
            uintptr_t fat_ar, fat_dr;
        } v_cons;
        struct {
            size_t lib_index, fn_index;
        } v_func;
        struct vm_string v_string;
        uintptr_t v_cfunc;
    };
};

static inline int ref_q(uint64_t w) {
    return (w & FLAG_REF) != 0;
}

static inline int integer_q(uint64_t w) {
    return !(w & FLAG_REF);
}

static inline int null_q(uint64_t w) {
    return w == FLAG_REF;
}

static inline struct vm_value *getref(uint64_t w) {
    assert(ref_q(w));
    return (struct vm_value *) (w << 1);
}

static inline int string_q(uint64_t w) {
    return !null_q(w) && ref_q(w) && getref(w)->type == VT_STRING;
}

static inline int cons_q(uint64_t w) {
    if (ref_q(w)) {
        return null_q(w) || getref(w)->type == VT_CONS;
    } else {
        return 0;
    }
}

static inline int func_q(uint64_t w) {
    return ref_q(w) && !null_q(w) && getref(w)->type == VT_FUNC;
}

static inline int cfunc_q(uint64_t w) {
    return ref_q(w) && !null_q(w) && getref(w)->type == VT_CFUNC;
}

static inline int pair_q(uint64_t w) {
    return ref_q(w) && (!null_q(w) && getref(w)->type == VT_CONS);
}

void vm_value_ref(struct vm_value *v);
int vm_value_unref(struct vm_value *v);

static inline void vm_ref(uint64_t w) {
    if (ref_q(w)) {
        vm_value_ref(getref(w));
    }
}
static inline int vm_unref(uint64_t w) {
    if (ref_q(w)) {
        return vm_value_unref(getref(w));
    }
    return 0;
}

void vm_value_free(struct vm_value *val);

struct vm_value *vm_cons(uint64_t w0, uint64_t w1);
struct vm_value *vm_makestr(const char *str);
struct vm_value *vm_func(size_t lib_index, size_t fn_index);
struct vm_value *vm_cfunc(uintptr_t address);

void vm_print(FILE *dst, uint64_t w);