C++ Outbuffer::size方法代码示例

void unittest_LEB128()
{
    Outbuffer buf;

    static int values[] =
    {
        0,1,2,3,300,4000,50000,600000,
        -0,-1,-2,-3,-300,-4000,-50000,-600000,
    };

    for (size_t i = 0; i < sizeof(values)/sizeof(values[0]); ++i)
    {
        const int value = values[i];

        buf.reset();
        buf.writeuLEB128(value);
        assert(buf.size() == uLEB128size(value));
        unsigned char *p = buf.buf;
        int result = uLEB128(&p);
        assert(p == buf.p);
        assert(result == value);

        buf.reset();
        buf.writesLEB128(value);
        assert(buf.size() == sLEB128size(value));
        p = buf.buf;
        result = sLEB128(&p);
        assert(p == buf.p);
        assert(result == value);
    }
}

void unittest_actionTableInsert()
{
    Outbuffer atbuf;
    static int tt1[] = { 1,2,3 };
    static int tt2[] = { 2 };

    int offset = -1;
    for (size_t i = sizeof(tt1)/sizeof(tt1[0]); i--; )
    {
        offset = actionTableInsert(&atbuf, tt1[i], offset);
    }
    offset = -1;
    for (size_t i = sizeof(tt2)/sizeof(tt2[0]); i--; )
    {
        offset = actionTableInsert(&atbuf, tt2[i], offset);
    }

    static unsigned char result[] = { 3,0,2,0x7D,1,0x7D,2,0 };
    //for (int i = 0; i < atbuf.size(); ++i) printf(" %02x\n", atbuf.buf[i]);
    assert(sizeof(result) == atbuf.size());
    int r = memcmp(result, atbuf.buf, atbuf.size());
    assert(r == 0);
}

/******************************************
 * write lexical scope records up to the line where the symbol sa is created
 * if sa == NULL, flush all remaining records
 */
void cv8_writeLexicalScope(Funcsym *s, symbol *sa, VarStatistics* vs)
{
    if (vs->cntUsedVarStats == 0)
        return;

    unsigned line;
    if(sa)
    {
        line = sa->lnoscopestart + 1;
    }
    else
    {
        // flush all
        line = vs->firstVarStatsLine + vs->cntUsedVarStats;
    }
    while (vs->nextVarStatsLine < line && vs->nextVarStatsLine < vs->firstVarStatsLine + vs->cntUsedVarStats)
    {
        Outbuffer *buf = currentfuncdata.f1buf;
        unsigned idx = vs->nextVarStatsLine - vs->firstVarStatsLine;
        for(int d = 0; d < vs->varStats[idx].numDel; d++)
        {
            static unsigned short s_end[] = { 2, S_END };
            buf->write(s_end, sizeof(s_end));
        }
        for(int n = 0; n < vs->varStats[idx].numNew; n++)
        {
            unsigned offset = vs->varStats[idx].offset;
            unsigned length = vs->varStats[vs->varStats[idx].endLine - vs->firstVarStatsLine].offset - offset;
            unsigned soffset = buf->size();
            // parent and end to be filled by linker
            block_v3_data block32 = { sizeof(block_v3_data) - 2, S_BLOCK_V3, 0, 0, length, offset, 0, { 0 } };
            buf->write(&block32, sizeof(block32));
            size_t offOffset = (char*)&block32.offset - (char*)&block32;

            F1_Fixups f1f;
            f1f.s = s;
            f1f.offset = soffset + offOffset;
            f1f.value = offset;
            currentfuncdata.f1fixup->write(&f1f, sizeof(f1f));
        }
        vs->nextVarStatsLine++;
    }
}

void cv8_outsym(Symbol *s)
{
    //printf("cv8_outsym(s = '%s')\n", s->Sident);
    //type_print(s->Stype);
    //symbol_print(s);
    if (s->Sflags & SFLnodebug)
        return;

    idx_t typidx = cv_typidx(s->Stype);
    //printf("typidx = %x\n", typidx);
    const char *id = s->prettyIdent ? s->prettyIdent : prettyident(s);
    size_t len = strlen(id);

    if(len > CV8_MAX_SYMBOL_LENGTH)
        len = CV8_MAX_SYMBOL_LENGTH;

    F1_Fixups f1f;
    Outbuffer *buf = currentfuncdata.f1buf;

    unsigned sr;
    unsigned base;
    switch (s->Sclass)
    {
        case SCparameter:
        case SCregpar:
        case SCshadowreg:
            if (s->Sfl == FLreg)
            {
                s->Sfl = FLpara;
                cv8_outsym(s);
                s->Sfl = FLreg;
                goto case_register;
            }
            base = Para.size - BPoff;    // cancel out add of BPoff
            goto L1;
        case SCauto:
            if (s->Sfl == FLreg)
                goto case_register;
        case_auto:
            base = Auto.size;
        L1:
#if 1
            // Register relative addressing
            buf->reserve(2 + 2 + 4 + 4 + 2 + len + 1);
            buf->writeWordn( 2 + 4 + 4 + 2 + len + 1);
            buf->writeWordn(0x1111);
            buf->write32(s->Soffset + base + BPoff);
            buf->write32(typidx);
            buf->writeWordn(I64 ? 334 : 22);       // relative to RBP/EBP
            cv8_writename(buf, id, len);
            buf->writeByte(0);
#else
            // This is supposed to work, implicit BP relative addressing, but it does not
            buf->reserve(2 + 2 + 4 + 4 + len + 1);
            buf->writeWordn( 2 + 4 + 4 + len + 1);
            buf->writeWordn(S_BPREL_V3);
            buf->write32(s->Soffset + base + BPoff);
            buf->write32(typidx);
            cv8_writename(buf, id, len);
            buf->writeByte(0);
#endif
            break;

        case SCbprel:
            base = -BPoff;
            goto L1;

        case SCfastpar:
            if (s->Sfl != FLreg)
            {   base = Fast.size;
                goto L1;
            }
            goto L2;

        case SCregister:
            if (s->Sfl != FLreg)
                goto case_auto;
        case SCpseudo:
        case_register:
        L2:
            buf->reserve(2 + 2 + 4 + 2 + len + 1);
            buf->writeWordn( 2 + 4 + 2 + len + 1);
            buf->writeWordn(S_REGISTER_V3);
            buf->write32(typidx);
            buf->writeWordn(cv8_regnum(s));
            cv8_writename(buf, id, len);
            buf->writeByte(0);
            break;

        case SCextern:
            break;

        case SCstatic:
        case SClocstat:
            sr = S_LDATA_V3;
            goto Ldata;
        case SCglobal:
        case SCcomdat:
        case SCcomdef:
            sr = S_GDATA_V3;
//.........这里部分代码省略.........

void cv8_func_term(Symbol *sfunc)
{
    //printf("cv8_func_term(%s)\n", sfunc->Sident);

    assert(currentfuncdata.sfunc == sfunc);
    currentfuncdata.section_length = retoffset + retsize;

    funcdata->write(&currentfuncdata, sizeof(currentfuncdata));

    // Write function symbol
    assert(tyfunc(sfunc->ty()));
    idx_t typidx;
    func_t* fn = sfunc->Sfunc;
    if(fn->Fclass)
    {
        // generate member function type info
        // it would be nicer if this could be in cv4_typidx, but the function info is not available there
        unsigned nparam;
        unsigned char call = cv4_callconv(sfunc->Stype);
        idx_t paramidx = cv4_arglist(sfunc->Stype,&nparam);
        unsigned next = cv4_typidx(sfunc->Stype->Tnext);

        type* classtype = (type*)fn->Fclass;
        unsigned classidx = cv4_typidx(classtype);
        type *tp = type_allocn(TYnptr, classtype);
        unsigned thisidx = cv4_typidx(tp);  // TODO
        debtyp_t *d = debtyp_alloc(2 + 4 + 4 + 4 + 1 + 1 + 2 + 4 + 4);
        TOWORD(d->data,LF_MFUNCTION_V2);
        TOLONG(d->data + 2,next);       // return type
        TOLONG(d->data + 6,classidx);   // class type
        TOLONG(d->data + 10,thisidx);   // this type
        d->data[14] = call;
        d->data[15] = 0;                // reserved
        TOWORD(d->data + 16,nparam);
        TOLONG(d->data + 18,paramidx);
        TOLONG(d->data + 22,0);  // this adjust
        typidx = cv_debtyp(d);
    }
    else
        typidx = cv_typidx(sfunc->Stype);

    const char *id = sfunc->prettyIdent ? sfunc->prettyIdent : prettyident(sfunc);
    size_t len = strlen(id);
    if(len > CV8_MAX_SYMBOL_LENGTH)
        len = CV8_MAX_SYMBOL_LENGTH;
    /*
     *  2       length (not including these 2 bytes)
     *  2       S_GPROC_V3
     *  4       parent
     *  4       pend
     *  4       pnext
     *  4       size of function
     *  4       size of function prolog
     *  4       offset to function epilog
     *  4       type index
     *  6       seg:offset of function start
     *  1       flags
     *  n       0 terminated name string
     */
    Outbuffer *buf = currentfuncdata.f1buf;
    buf->reserve(2 + 2 + 4 * 7 + 6 + 1 + len + 1);
    buf->writeWordn( 2 + 4 * 7 + 6 + 1 + len + 1);
    buf->writeWordn(sfunc->Sclass == SCstatic ? S_LPROC_V3 : S_GPROC_V3);
    buf->write32(0);            // parent
    buf->write32(0);            // pend
    buf->write32(0);            // pnext
    buf->write32(currentfuncdata.section_length);       // size of function
    buf->write32(startoffset);          // size of prolog
    buf->write32(retoffset);                    // offset to epilog
    buf->write32(typidx);

    F1_Fixups f1f;
    f1f.s = sfunc;
    f1f.offset = buf->size();
    currentfuncdata.f1fixup->write(&f1f, sizeof(f1f));
    buf->write32(0);
    buf->writeWordn(0);

    buf->writeByte(0);
    buf->writen(id, len);
    buf->writeByte(0);

    // Write local symbol table
    bool endarg = false;
    for (SYMIDX si = 0; si < globsym.top; si++)
    {   //printf("globsym.tab[%d] = %p\n",si,globsym.tab[si]);
        symbol *sa = globsym.tab[si];
        if (endarg == false &&
            sa->Sclass != SCparameter &&
            sa->Sclass != SCfastpar &&
            sa->Sclass != SCshadowreg)
        {
            buf->writeWord(2);
            buf->writeWord(S_ENDARG);
            endarg = true;
        }
        cv8_outsym(sa);
    }

    /* Put out function return record S_RETURN
//.........这里部分代码省略.........

void genDwarfEh(Funcsym *sfunc, int seg, Outbuffer *et, bool scancode, unsigned startoffset, unsigned retoffset)
{
#ifdef DEBUG
    unittest_dwarfeh();
#endif

    /* LPstart = encoding of LPbase
     * LPbase = landing pad base (normally omitted)
     * TType = encoding of TTbase
     * TTbase = offset from next byte to past end of Type Table
     * CallSiteFormat = encoding of fields in Call Site Table
     * CallSiteTableSize = size in bytes of Call Site Table
     * Call Site Table[]:
     *    CallSiteStart
     *    CallSiteRange
     *    LandingPad
     *    ActionRecordPtr
     * Action Table
     *    TypeFilter
     *    NextRecordPtr
     * Type Table
     */

    et->reserve(100);
    block *startblock = sfunc->Sfunc->Fstartblock;
    //printf("genDwarfEh: func = %s, offset = x%x, startblock->Boffset = x%x, scancode = %d startoffset=x%x, retoffset=x%x\n",
      //sfunc->Sident, (int)sfunc->Soffset, (int)startblock->Boffset, scancode, startoffset, retoffset);

#if 0
    printf("------- before ----------\n");
    for (block *b = startblock; b; b = b->Bnext) WRblock(b);
    printf("-------------------------\n");
#endif

    unsigned startsize = et->size();
    assert((startsize & 3) == 0);       // should be aligned

    DwEhTable *deh = &dwehtable;
    deh->dim = 0;
    Outbuffer atbuf;
    Outbuffer cstbuf;

    /* Build deh table, and Action Table
     */
    int index = -1;
    block *bprev = NULL;
    // The first entry encompasses the entire function
    {
        unsigned i = deh->push();
        DwEhTableEntry *d = deh->index(i);
        d->start = startblock->Boffset + startoffset;
        d->end = startblock->Boffset + retoffset;
        d->lpad = 0;                    // no cleanup, no catches
        index = i;
    }
    for (block *b = startblock; b; b = b->Bnext)
    {
        if (index > 0 && b->Btry == bprev)
        {
            DwEhTableEntry *d = deh->index(index);
            d->end = b->Boffset;
            index = d->prev;
            if (bprev)
                bprev = bprev->Btry;
        }
        if (b->BC == BC_try)
        {
            unsigned i = deh->push();
            DwEhTableEntry *d = deh->index(i);
            d->start = b->Boffset;

            block *bf = b->nthSucc(1);
            if (bf->BC == BCjcatch)
            {
                d->lpad = bf->Boffset;
                d->bcatch = bf;
                unsigned *pat = bf->BS.BIJCATCH.actionTable;
                unsigned length = pat[0];
                assert(length);
                unsigned offset = -1;
                for (unsigned u = length; u; --u)
                {
                    /* Buy doing depth-first insertion into the Action Table,
                     * we can combine common tails.
                     */
                    offset = actionTableInsert(&atbuf, pat[u], offset);
                }
                d->action = offset + 1;
            }
            else
                d->lpad = bf->nthSucc(0)->Boffset;
            d->prev = index;
            index = i;
            bprev = b->Btry;
        }
        if (scancode)
        {
            unsigned coffset = b->Boffset;
            int n = 0;
            for (code *c = b->Bcode; c; c = code_next(c))
//.........这里部分代码省略.........