ireach.c

CC386 is a general-purpose 32-bit C compiler. It is not an optimizing compiler but given that the co

                    if (head->dc.left)
                    {
                        k = findPointer(head->dc.left);
                        if (k < pointer_count)
                        {
                            for (j = 1; j < source_count; j++)
                            if (isset(temparray4 + k * sourcebytes, j))
                            {
                                enter_definition(sourcearray[j], head);
                            }
                        }
                    }
                    if (head->dc.right)
                    {
                        k = findPointer(head->dc.right);
                        if (k < pointer_count)
                        {
                            for (j = 1; j < source_count; j++)
                            if (isset(temparray4 + k * sourcebytes, j))
                            {
                                enter_definition(sourcearray[j], head);
                            }
                        }
                    }
                    break;
                case i_gosub:
                    l->callcount++;
                    break;
                    break;

            }
            ptrindex(head, l, temparray4);
            head = head->fwd;
        }
    }
}

//-------------------------------------------------------------------------

void CreateBitArrays(void)
{
    int i;
    definition_bytes = (definition_count + 8) / 8;
    if (definition_bytes % 4)
        definition_bytes += 4-definition_bytes % 4;
    for (i = 0; i < blocknum; i++)
    {
        blockarray[i]->block->p_gen = oalloc(definition_bytes);
        blockarray[i]->block->p_kill = oalloc(definition_bytes);
        blockarray[i]->block->p_in = oalloc(definition_bytes);
        blockarray[i]->block->p_out = oalloc(definition_bytes);
    }
    temparray1 = oalloc(definition_bytes);
    temparray2 = oalloc(definition_bytes);
}

//-------------------------------------------------------------------------

void CalculateBlockBasics(void)
{
    int i, j, k, left, right, ans;
    int ptr, ptr2, gencount, pgen, pagen, def2;
    int left1, right1, ans1;
    LIST *l1;
    for (i = 0; i < blocknum; i++)
    {
        BLOCK *l = blockarray[i]->block;
        QUAD *list = l->head;
        memcpy(temparray4, l->p_pin, sourcebytes *pointer_count);
        while (list && list->back != l->tail)
        {
            ptr = INT_MAX;
            gencount = 0;
            pgen =  - 1;
            switch (list->dc.opcode)
            {
                case i_add:
                case i_sub:
                case i_udiv:
                case i_umod:
                case i_sdiv:
                case i_smod:
                case i_umul:
                case i_smul:
                case i_lsl:
                case i_lsr:
                case i_asl:
                case i_asr:
                case i_neg:
                case i_not:
                case i_and:
                case i_or:
                case i_eor:
                case i_setne:
                case i_sete:
                case i_setc:
                case i_seta:
                case i_setnc:
                case i_setbe:
                case i_setl:
                case i_setg:
                case i_setle:
                case i_setge:
                case i_assn:
                    // start reaching defs
                    memset(temparray1, 0, definition_bytes);
                    memset(temparray2, 0, definition_bytes);
                    setbit(temparray1, list->definition); // gen
                    // gen bits
                    l1 = findans(defhash2, list->ans);
                    if (!l1)
                        DIAG("CalculateBlockBasics - can't find defintion");
                    else
                    {
                        while (l1)
                        {
                            int d = ((QUAD*)(l1->data))->definition;
                            if (list->definition != d)
                                setbit(temparray2, d);
                            l1 = l1->link;
                        }
                    }
                    if (list->ans->mode == i_ind)
                    {
                        BYTE *t4;
                        ptr = findPointer(list->ans);
                        if (ptr < pointer_count)
                        {
                            t4 = temparray4 + ptr * sourcebytes;
                            if (isset(t4, 0))
                            {
                                memset(temparray1, 0xff, definition_bytes);
                            }
                            else
                            {
                                for (j = 1; j < source_count; j++)
                                {
                                    if (isset(t4, j))
                                    {
                                        def2 = FindDefinition(j, list);
                                        if (def2 ==  - 1)
                                            DIAG(
                                                "CalculateBlockBasics - can't find def");
                                        else
                                        {
                                            // gen and kill in presence of pointers
                                            setbit(temparray1, def2);
                                            clearbit(temparray2, def2);
                                        }
                                    }
                                }
                            }
                        }
                    }
                    // finish reaching defs
                    for (j = 0; j < definition_bytes; j += 4)
                    {
                        *(unsigned*)(l->p_gen + j) &= ~*(unsigned*)(temparray2 
                            + j);
                        *(unsigned*)(l->p_gen + j) |= *(unsigned*)(temparray1 +
                            j);
                        *(unsigned*)(l->p_kill + j) &= ~*(unsigned*)(temparray1
                            + j);
                        *(unsigned*)(l->p_kill + j) |= *(unsigned*)(temparray2 
                            + j);
                    }
                    // FALLTHROUGH
                case i_coswitch:
                case i_jc:
                case i_ja:
                case i_je:
                case i_jnc:
                case i_jbe:
                case i_jne:
                case i_jl:
                case i_jg:
                case i_jle:
                case i_jge:
                case i_parm:
                    if (list->dc.opcode == i_parm)
                    {
                        SYM *sp = varsp(list->dc.left);
                        memset(temparray1, 0, definition_bytes);
                        memset(temparray2, 0, definition_bytes);
                        if (sp && list->dc.left->mode == i_immed)
                        {
                            l1 = findans(defhash2, sp->imvalue);
                            if (!l1)
                                DIAG(
                                    "CalculateBlockBasics - can't find defintion");
                            else
                            {
                                while (l1)
                                {
                                    int d = ((QUAD*)(l1->data))->definition;
                                    if (list->definition != d)
                                        setbit(temparray2, d);
                                    l1 = l1->link;
                                }
                            }
                        }
                        else if (sp && list->dc.left->mode == i_direct)
                        {
                            ptr = findPointer(list->dc.left);
                            if (ptr < pointer_count)
                            {
                                BYTE *t4 = temparray4 + ptr * sourcebytes;
                                if (isset(t4, 0))
                                {
                                    memset(temparray1, 0xff, definition_bytes);
                                }
                                else
                                {
                                    for (j = 1; j < source_count; j++)
                                    {
                                        if (isset(t4, j))
                                        {
                                            def2 = FindDefinition(j, list);
                                            if (def2 ==  - 1)
                                                DIAG(
                                                    "CalculateBlockBasics - can't find def");
                                            else
                                            {
                                                // gen and kill in presence of pointers
                                                setbit(temparray1, def2);
                                                clearbit(temparray2, def2);
                                            }
                                        }
                                    }
                                }
                            }
                        }
                        for (j = 0; j < definition_bytes; j += 4)
                        {
                            *(unsigned*)(l->p_gen + j) &= ~*(unsigned*)
                                (temparray2 + j);
                            *(unsigned*)(l->p_gen + j) |= *(unsigned*)
                                (temparray1 + j);
                            *(unsigned*)(l->p_kill + j) &= ~*(unsigned*)
                                (temparray1 + j);
                            *(unsigned*)(l->p_kill + j) |= *(unsigned*)
                                (temparray2 + j);
                        }
                    }
                    break;
                case i_gosub:
                    // kill globals
                    for (j = 0; j < definition_count; j++)
                    {
                        IMODE *s = defiarray[j]->ans;
                        switch (s->offset->nodetype)
                        {
                        case en_nacon:
                        case en_napccon:
                        case en_nalabcon:
                        case en_labcon:
                        case en_absacon:
                            if (s->mode == i_direct)
                            {
                                clearbit(l->p_gen, j);
                                setbit(l->p_kill, j);
                            }
                            else if (s->mode == i_ind)
                            {
                                BYTE *t4;
                                ptr = findPointer(list->ans);
                                if (ptr < pointer_count)
                                {
                                    t4 = temparray4 + ptr * sourcebytes;
                                    if (isset(t4, 0))
                                    {
                                        memset(temparray1, 0xff,
                                            definition_bytes);
                                    }
                                    else
                                    {
                                        for (k = 1; k < source_count; k++)
                                        {
                                            if (isset(t4, k))
                                            {
                                                clearbit(l->p_gen, k);
                                                setbit(l->p_kill, k);
                                            }
                                        }
                                    }
                                }
                            }
                        }
                    }
            }
            ptrindex(list, l, temparray4);
            list = list->fwd;
        }
    }
}

//-------------------------------------------------------------------------

void CalculateReaching(void)
{
    int i, changed, j;
    for (i = 0; i < blocknum; i++)
        memcpy(blockarray[i]->block->p_out, blockarray[i]->block->p_gen,
            definition_bytes);
    do
    {
        changed = FALSE;
        for (i = 0; i < blocknum; i++)
        {
            BLOCK *t = blockarray[dfst[i]]->block;
            BLOCKLIST *l = t->flowback;
            memset(t->p_in, 0, definition_bytes);
            while (l)
            {
                for (j = 0; j < definition_bytes; j++)t->p_in[j] |= l->block
                    ->p_out[j];
                l = l->link;
            }
            for (j = 0; j < definition_bytes; j++)
            {
                int v = t->p_out[j];
                t->p_out[j] = t->p_gen[j] | (t->p_in[j] &~t->p_kill[j]);
                changed |= (v != t->p_out[j]);
            }
        }
    }
    while (changed)
        ;

}

//-------------------------------------------------------------------------

void CalculateEquations(QUAD *head)
{
    return ;
    defhash = oalloc(sizeof(LIST2*) * DHASH);
    defhash2 = oalloc(sizeof(LIST3*) * DHASH);
    CountDefinitions();
    CreateBitArrays();
    CalculateBlockBasics();
    CalculateReaching();
    #ifdef DUMP_GCSE_INFO
        dumpeqn();
    #endif 
}