shithub: mc

ref: a065812f7718a33b09cb653949436dc1ab544756
dir: /6/typeinfo.c/

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#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <inttypes.h>
#include <ctype.h>
#include <string.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

#include "parse.h"
#include "mi.h"
#include "asm.h"
#include "../config.h"

#define Tdindirect 0x80

Blob *tydescsub(Type *ty);

size_t blobsz(Blob *b)
{
    size_t n;
    size_t i;

    switch (b->type) {
        case Bti8:      return 1;       break;
        case Bti16:     return 2;       break;
        case Bti32:     return 4;       break;
        case Bti64:     return 8;       break;
        case Btref:     return 8;       break;
        case Btbytes:   return b->bytes.len;    break;
        case Btimin:
            if (b->ival >= 1ULL << 56)
                die("packed int too big");

            for (i = 1; i < 8; i++)
                if (b->ival < 1ULL << (7*i))
                    return i;
            die("impossible blob size");
            break;
        case Btseq:
            n = 0;
            for (i = 0; i < b->seq.nsub; i++)
                n += blobsz(b->seq.sub[i]);
            return n;
            break;
        default:
            die("unknown blob type");
    }
    return 0;
}

void namevec(Blob ***sub, size_t *nsub, Node *n)
{
    char *buf;
    size_t len;

    if (n->name.ns) {
        len = strlen(n->name.name) + strlen(n->name.ns) + 1;
        buf = xalloc(len + 1);
        bprintf(buf, len + 1, "%s.%s", n->name.ns, n->name.name);
    } else {
        len = strlen(n->name.name);
        buf = xalloc(len + 1);
        bprintf(buf, len + 1, "%s", n->name.name);
    }
    lappend(sub, nsub, mkblobi(Btimin, len));
    lappend(sub, nsub, mkblobbytes(buf, len));
}

static void structmemb(Blob ***sub, size_t *nsub, Node *sdecl)
{
    Blob *b;

    namevec(sub, nsub, sdecl->decl.name);
    b = tydescsub(sdecl->decl.type);
    lappend(sub, nsub, b);
}

static void unionmemb(Blob ***sub, size_t *nsub, Ucon *ucon)
{
    namevec(sub, nsub, ucon->name);
    if (ucon->etype) {
        lappend(sub, nsub, tydescsub(ucon->etype));
    } else  {
        lappend(sub, nsub, mkblobi(Btimin, 1));
        lappend(sub, nsub, mkblobi(Bti8, Tybad));
    }
}

static void encodetypeinfo(Blob ***sub, size_t *nsub, Type *t)
{
    lappend(sub, nsub, mkblobi(Btimin, tysize(t)));
    lappend(sub, nsub, mkblobi(Btimin, tyalign(t)));
}

Blob *tydescsub(Type *ty)
{
    Blob **sub, *sz, *bt, *b;
    size_t i, nsub;
    char buf[512];
    uint8_t tt;
    Node *len;

    sub = NULL;
    nsub = 0;
    /* names are pulled out of line */
    tt = ty->type;
    /* tyvars can get tagged, but aren't desired */
    if (ty->type == Tyvar)
        return NULL;

    if (ty->type == Tyname)
        tt |= Tdindirect;
    sz = mkblobi(Btimin, 0);
    bt = mkblobi(Bti8, tt);
    lappend(&sub, &nsub, bt);
    switch (ty->type) {
        case Ntypes: case Tyvar: case Tybad: case Typaram:
        case Tygeneric: case Tycode: case Tyunres:
            die("invalid type in tydesc");    break;

        /* atomic types -- nothing else to do */
        case Tyvoid: case Tychar: case Tybool: case Tyint8:
        case Tyint16: case Tyint: case Tyint32: case Tyint64:
        case Tybyte: case Tyuint8: case Tyuint16:
        case Tyuint: case Tyuint32: case Tyuint64:
        case Tyflt32: case Tyflt64: case Tyvalist:
            break;

        case Typtr:
            lappend(&sub, &nsub, tydescsub(ty->sub[0]));
            break;
        case Tyslice:
            lappend(&sub, &nsub, tydescsub(ty->sub[0]));
            break;
        case Tyarray:
            encodetypeinfo(&sub, &nsub, ty);
            ty->asize = fold(ty->asize, 1);
            len = ty->asize;
            if (len) {
                assert(len->type == Nexpr);
                len = len->expr.args[0];
                assert(len->type == Nlit && len->lit.littype == Lint);
                lappend(&sub, &nsub, mkblobi(Btimin, len->lit.intval));
            } else {
                lappend(&sub, &nsub, mkblobi(Btimin, 0));
            }

            lappend(&sub, &nsub, tydescsub(ty->sub[0]));
            break;
        case Tyfunc:
            lappend(&sub, &nsub, mkblobi(Btimin, ty->nsub));
            for (i = 0; i < ty->nsub; i++)
                lappend(&sub, &nsub, tydescsub(ty->sub[i]));
            break;
        case Tytuple:
            encodetypeinfo(&sub, &nsub, ty);
            lappend(&sub, &nsub, mkblobi(Btimin, ty->nsub));
            for (i = 0; i < ty->nsub; i++)
                lappend(&sub, &nsub, tydescsub(ty->sub[i]));
            break;
        case Tystruct:
            encodetypeinfo(&sub, &nsub, ty);
            lappend(&sub, &nsub, mkblobi(Btimin, ty->nmemb));
            for (i = 0; i < ty->nmemb; i++)
                structmemb(&sub, &nsub, ty->sdecls[i]);
            break;
        case Tyunion:
            encodetypeinfo(&sub, &nsub, ty);
            lappend(&sub, &nsub, mkblobi(Btimin, ty->nmemb));
            for (i = 0; i < ty->nmemb; i++)
                unionmemb(&sub, &nsub, ty->udecls[i]);
            break;
        case Tyname:
            i = bprintf(buf, sizeof buf, "%s", Symprefix);
            tydescid(buf + i, sizeof buf - i, ty);
            lappend(&sub, &nsub, mkblobref(buf, 0, ty->isimport || ty->vis == Visexport));
            break;
    }
    b = mkblobseq(sub, nsub);
    sz->ival = blobsz(b);
    linsert(&b->seq.sub, &b->seq.nsub, 0, sz);
    return b;
}

Blob *namedesc(Type *ty)
{
    Blob **sub;
    size_t nsub;

    sub = NULL;
    nsub = 0;
    lappend(&sub, &nsub, mkblobi(Bti8, Tyname));
    namevec(&sub, &nsub, ty->name);
    lappend(&sub, &nsub, tydescsub(ty->sub[0]));
    return mkblobseq(sub, nsub);
}

Blob *tydescblob(Type *ty)
{
    char buf[512];
    Blob *b, *sz, *sub;

    if (ty->type == Tyname && hasparams(ty))
        return NULL;

    if (ty->type == Tyname) {
        b = mkblobseq(NULL, 0);
        sz = mkblobi(Btimin, 0);
        sub = namedesc(ty);
        sz->ival = blobsz(sub);
        lappend(&b->seq.sub, &b->seq.nsub, sz);
        lappend(&b->seq.sub, &b->seq.nsub, sub);
        if (ty->vis == Visexport)
            b->isglobl = 1;
    } else {
        b = tydescsub(ty);
    }
    tydescid(buf, sizeof buf, ty);
    b->lbl = strdup(buf);
    return b;
}

size_t tysize(Type *t)
{
    size_t sz;
    size_t i;

    sz = 0;
    if (!t)
        die("size of empty type => bailing.");
    switch (t->type) {
        case Tyvoid:
            return 0;
        case Tybool: case Tyint8:
        case Tybyte: case Tyuint8:
            return 1;
        case Tyint16: case Tyuint16:
            return 2;
        case Tyint: case Tyint32:
        case Tyuint: case Tyuint32:
        case Tychar:  /* utf32 */
            return 4;

        case Typtr:
        case Tyvalist: /* ptr to first element of valist */
            return Ptrsz;

        case Tyint64:
        case Tyuint64:
            return 8;

            /*end integer types*/
        case Tyflt32:
            return 4;
        case Tyflt64:
            return 8;

        case Tycode:
            return Ptrsz;
        case Tyfunc:
            return 2*Ptrsz;
        case Tyslice:
            return 2*Ptrsz; /* len; ptr */
        case Tyname:
            return tysize(t->sub[0]);
        case Tyarray:
            if (!t->asize)
                return 0;
            t->asize = fold(t->asize, 1);
            assert(exprop(t->asize) == Olit);
            return t->asize->expr.args[0]->lit.intval * tysize(t->sub[0]);
        case Tytuple:
            for (i = 0; i < t->nsub; i++) {
                sz = alignto(sz, t->sub[i]);
                sz += tysize(t->sub[i]);
            }
            sz = alignto(sz, t);
            return sz;
            break;
        case Tystruct:
            for (i = 0; i < t->nmemb; i++) {
                sz = alignto(sz, decltype(t->sdecls[i]));
                sz += size(t->sdecls[i]);
            }
            sz = alignto(sz, t);
            return sz;
            break;
        case Tyunion:
            sz = Wordsz;
            for (i = 0; i < t->nmemb; i++)
                if (t->udecls[i]->etype)
                    sz = max(sz, tysize(t->udecls[i]->etype) + Wordsz);
            return align(sz, Ptrsz);
            break;
        case Tygeneric: case Tybad: case Tyvar:
        case Typaram: case Tyunres: case Ntypes:
            die("Type %s does not have size; why did it get down to here?", tystr(t));
            break;
    }
    return -1;
}

size_t tyalign(Type *ty)
{
    size_t align, i;

    align = 1;
    switch (ty->type) {
        case Tyarray:
            align = tyalign(ty->sub[0]);
            break;
        case Tytuple:
            for (i = 0; i < ty->nsub; i++)
                align = max(align, tyalign(ty->sub[0]));
            break;
        case Tyunion:
            align = 4;
            for (i = 0; i < ty->nmemb; i++)
                if (ty->udecls[i]->etype)
                    align = max(align, tyalign(ty->udecls[i]->etype));
            break;
        case Tystruct:
            for (i = 0; i < ty->nmemb; i++)
                align = max(align, tyalign(decltype(ty->sdecls[i])));
            break;
        default:
            align = tysize(ty);
    }
    return min(align, Ptrsz);
}

/* gets the byte offset of 'memb' within the aggregate type 'aggr' */
ssize_t tyoffset(Type *ty, Node *memb)
{
    size_t i;
    size_t off;

    ty = tybase(ty);
    if (ty->type == Typtr)
        ty = tybase(ty->sub[0]);

    assert(ty->type == Tystruct);
    off = 0;
    for (i = 0; i < ty->nmemb; i++) {
        off = alignto(off, decltype(ty->sdecls[i]));
        if (!strcmp(namestr(memb), declname(ty->sdecls[i])))
            return off;
        off += size(ty->sdecls[i]);
    }
    die("bad offset");
    return 0;
}

size_t size(Node *n)
{
    Type *t;

    if (n->type == Nexpr)
        t = n->expr.type;
    else
        t = n->decl.type;
    return tysize(t);
}

ssize_t offset(Node *aggr, Node *memb)
{
    return tyoffset(exprtype(aggr), memb);
}