Example #1
0
static void sliceStructs_Gather(SymInfo *sia, elem *e)
{
    while (1)
    {
        switch (e->Eoper)
        {
            case OPvar:
            {
                SYMIDX si = e->EV.sp.Vsym->Ssymnum;
                if (si >= 0 && sia[si].canSlice)
                {
                    assert(si < globsym.top);
                    unsigned sz = tysize(e->Ety);
                    if (sz == 2 * REGSIZE && !tyfv(e->Ety))
                    {
                        // Rewritten as OPpair later
                    }
                    else if (sz == REGSIZE &&
                        (e->Eoffset == 0 || e->Eoffset == REGSIZE))
                    {
                        if (!sia[si].accessSlice)
                        {
                            sia[si].ty0 = TYnptr;
                            sia[si].ty1 = TYnptr;
                        }
                        sia[si].accessSlice = true;
                        if (e->Eoffset == 0)
                            sia[si].ty0 = tybasic(e->Ety);
                        else
                            sia[si].ty1 = tybasic(e->Ety);
                    }
                    else
                    {
                        sia[si].canSlice = false;
                    }
                }
                return;
            }

            default:
                if (OTassign(e->Eoper))
                {
                    if (OTbinary(e->Eoper))
                        sliceStructs_Gather(sia, e->E2);

                    // Assignment to a whole var will disallow SROA
                    if (e->E1->Eoper == OPvar)
                    {
                        elem *e1 = e->E1;
                        SYMIDX si = e1->EV.sp.Vsym->Ssymnum;
                        if (si >= 0 && sia[si].canSlice)
                        {
                            assert(si < globsym.top);
                            if (tysize(e1->Ety) != REGSIZE ||
                                (e1->Eoffset != 0 && e1->Eoffset != REGSIZE))
                            {
                                sia[si].canSlice = false;
                            }
                        }
                        return;
                    }
                    e = e->E1;
                    break;
                }
                if (OTunary(e->Eoper))
                {
                    e = e->E1;
                    break;
                }
                if (OTbinary(e->Eoper))
                {
                    sliceStructs_Gather(sia, e->E2);
                    e = e->E1;
                    break;
                }
                return;
        }
    }
}
Example #2
0
static void sliceStructs_Gather(SymInfo *sia, elem *e)
{
    while (1)
    {
        switch (e->Eoper)
        {
            case OPvar:
            {
                SYMIDX si = e->EV.sp.Vsym->Ssymnum;
                if (si >= 0 && sia[si].canSlice)
                {
                    assert(si < globsym.top);
                    unsigned sz = tysize(e->Ety);
                    if (sz == 2 * REGSIZE)
                    {
                        // Rewrite as OPpair later
                        sia[si].usePair = true;

                        /* OPpair cannot handle XMM registers, cdpair() and fixresult()
                         */
                        if (tyfloating(sia[si].ty0) || tyfloating(sia[si].ty1))
                            sia[si].canSlice = false;
                    }
                    else if (sz == REGSIZE &&
                        (e->Eoffset == 0 || e->Eoffset == REGSIZE))
                    {
                        if (!sia[si].accessSlice)
                        {
                            sia[si].ty0 = TYnptr;
                            sia[si].ty1 = TYnptr;
                        }
                        sia[si].accessSlice = true;
                        if (e->Eoffset == 0)
                            sia[si].ty0 = tybasic(e->Ety);
                        else
                            sia[si].ty1 = tybasic(e->Ety);
                        // Cannot slice float fields if the symbol is also accessed using OPpair (see above)
                        if (sia[si].usePair && (tyfloating(sia[si].ty0) || tyfloating(sia[si].ty1)))
                            sia[si].canSlice = false;
                    }
                    else
                    {
                        sia[si].canSlice = false;
                    }
                }
                return;
            }

            default:
                if (OTassign(e->Eoper))
                {
                    if (OTbinary(e->Eoper))
                        sliceStructs_Gather(sia, e->E2);

                    // Assignment to a whole var will disallow SROA
                    if (e->E1->Eoper == OPvar)
                    {
                        elem *e1 = e->E1;
                        SYMIDX si = e1->EV.sp.Vsym->Ssymnum;
                        if (si >= 0 && sia[si].canSlice)
                        {
                            assert(si < globsym.top);
                            if (tysize(e1->Ety) != REGSIZE ||
                                (e1->Eoffset != 0 && e1->Eoffset != REGSIZE))
                            {
                                sia[si].canSlice = false;
                            }
                        }
                        return;
                    }
                    e = e->E1;
                    break;
                }
                if (OTunary(e->Eoper))
                {
                    e = e->E1;
                    break;
                }
                if (OTbinary(e->Eoper))
                {
                    sliceStructs_Gather(sia, e->E2);
                    e = e->E1;
                    break;
                }
                return;
        }
    }
}