/**
* This function returns the last definition of a value. In case
* this value was last defined in a previous block, Phi nodes are
* inserted. If the part of the firm graph containing the definition
* is not yet constructed, a dummy Phi node is returned.
*
* @param block the current block
* @param pos the value number of the value searched
* @param mode the mode of this value (needed for Phi construction)
*/
static ir_node *get_r_value_internal(ir_node *block, int pos, ir_mode *mode)
{
ir_node *res = block->attr.block.graph_arr[pos];
if (res != NULL)
return res;
/* in a matured block we can immediately determine the phi arguments */
if (get_Block_matured(block)) {
ir_graph *const irg = get_irn_irg(block);
int const arity = get_irn_arity(block);
/* no predecessors: use unknown value */
if (arity == 0) {
if (block == get_irg_start_block(irg)) {
if (default_initialize_local_variable != NULL) {
ir_node *rem = get_r_cur_block(irg);
set_r_cur_block(irg, block);
res = default_initialize_local_variable(irg, mode, pos - 1);
set_r_cur_block(irg, rem);
} else {
res = new_r_Unknown(irg, mode);
}
} else {
goto bad; /* unreachable block, use Bad */
}
/* one predecessor just use its value */
} else if (arity == 1) {
ir_node *cfgpred = get_Block_cfgpred(block, 0);
if (is_Bad(cfgpred)) {
bad:
res = new_r_Bad(irg, mode);
} else {
ir_node *cfgpred_block = get_nodes_block(cfgpred);
res = get_r_value_internal(cfgpred_block, pos, mode);
}
} else {
/* multiple predecessors construct Phi */
res = new_rd_Phi0(NULL, block, mode, pos);
/* enter phi0 into our variable value table to break cycles
* arising from set_phi_arguments */
block->attr.block.graph_arr[pos] = res;
res = set_phi_arguments(res, pos);
}
} else {
/* in case of immature block we have to keep a Phi0 */
res = new_rd_Phi0(NULL, block, mode, pos);
/* enqueue phi so we can set arguments once the block matures */
res->attr.phi.next = block->attr.block.phis;
block->attr.block.phis = res;
}
block->attr.block.graph_arr[pos] = res;
return res;
}
static ir_node *get_vtable_ref(ir_type *type)
{
ir_entity *cls_vtable = oo_get_class_vtable_entity(type);
if (cls_vtable == NULL)
return NULL;
ir_graph *ccode = get_const_code_irg();
ir_node *addr = new_r_Address(ccode, cls_vtable);
unsigned offset
= ddispatch_get_vptr_points_to_index() * get_mode_size_bytes(mode_reference);
ir_mode *offset_mode = get_reference_offset_mode(mode_reference);
ir_node *cnst = new_r_Const_long(ccode, offset_mode, offset);
ir_node *block = get_r_cur_block(ccode);
ir_node *add = new_r_Add(block, addr, cnst);
return add;
}
ir_graph *new_const_code_irg(void)
{
ir_graph *const res = new_r_ir_graph(NULL, 0);
mature_immBlock(get_irg_end_block(res));
/* There is no Start node in the const_code_irg */
set_irg_start(res, new_r_Bad(res, mode_T));
set_irg_frame(res, new_r_Bad(res, mode_BAD));
set_irg_args(res, new_r_Bad(res, mode_T));
set_irg_initial_mem(res, new_r_Bad(res, mode_M));
set_r_store(res, get_irg_no_mem(res));
/* Set the visited flag high enough that the blocks will never be
* visited. */
ir_node *const body_block = get_r_cur_block(res);
set_irn_visited(body_block, -1);
set_Block_block_visited(body_block, -1);
ir_node *const start_block = get_irg_start_block(res);
set_Block_block_visited(start_block, -1);
set_irn_visited(start_block, -1);
return res;
}
