#include "cgen.h"
#include "fn.h"
#include "gl.h"
#include "stmt.h"
#include "qbe.h"
#include "ws.h"
#include <stdio.h>

int qbe_fn(const struct fn *fn, struct cgen *c)
{
    const struct pr *pr = fn->pr;
    const struct param *ret = pr->ret;
    const struct type *rt = NULL;
    const char *s = NULL;
    struct fn_cgen fnc = {0};

    c->fnc = &fnc;

    if (fn->gl && gl_cgen(fn->gl, c))
        return -1;

    switch (fn->linkage)
    {
    case STATIC:
        printf("function ");
        break;
    case EXTERNAL:
        printf("export function ");
        break;
    }

    if (ret)
    {
        rt = ret->entry->t;
        s = ret->entry->tk->s;
        printf("%s ", cgen_abity(ret->entry->t));
    }

    printf("$%s(", fn->tk->s);

    for (size_t i = 0; i < pr->nparams; i++)
    {
        const struct param *p = &pr->params[i];

        printf(" %s", cgen_abity(p->entry->t));
        printf(" %%__param_%s ", p->tk->s);

        if (i + 1 < pr->nparams)
            fputs(", ", stdout);
    }

    puts(") {\n@start");

    for (size_t i = 0; i < pr->nparams; i++)
    {
        const struct param *p = &pr->params[i];
        const struct type *t = p->entry->t;
        const char *s = p->tk->s;

        printf("%%%s_ =l alloc%zu %zu\n", s, t->align, t->sz);
        printf("store%s %%__param_%s, %%%s_\n", cgen_sz(t->sz), s, s);
    }

    if (ret)
        printf("%%%s_ =l alloc%zu %zu\n", s, rt->align, rt->sz);

    if (fn->ws && ws_cgen(fn->ws, c))
        return -1;

    for (const struct tmp *tmp = fn->tmps; tmp; tmp = tmp->next)
    {
        const struct stentry *e = &tmp->e;
        const struct type *t = tmp->e.t;

        printf("%%%s_ =l alloc%zu %zu\n", e->tk->s, t->align, t->sz);
    }

    for (size_t i = 0; i < fn->nstmts; i++)
        if (stmt_cgen(&fn->stmts[i], c))
            return -1;

    if (ret)
    {
        const char *t = cgen_tmp(rt->sz);

        printf("%%%s =%s load%s %%%s_\n", t, cgen_sz(rt->sz), cgen_load(rt), s);
        printf("ret %%%s", t);
    }
    else
        fputs("ret", stdout);

    puts("\n}");
    return 0;
}