예제 #1
0
파일: rm_bads.c 프로젝트: MatzeB/libfirm
/**
 * Block-walker, remove Bad block predecessors and shorten Phis.
 * Phi links must be up-to-date.
 */
static void block_remove_bads(ir_node *block)
{
	/* 1. Create a new block without Bad inputs */
	ir_graph  *irg     = get_irn_irg(block);
	const int  max     = get_Block_n_cfgpreds(block);
	ir_node  **new_in  = ALLOCAN(ir_node*, max);
	unsigned   new_max = 0;
	for (int i = 0; i < max; ++i) {
		ir_node *const block_pred = get_Block_cfgpred(block, i);
		if (!is_Bad(block_pred)) {
			new_in[new_max++] = block_pred;
		}
	}

	/* If the end block is unreachable, it might have zero predecessors. */
	if (new_max == 0) {
		ir_node *end_block = get_irg_end_block(irg);
		if (block == end_block) {
			set_irn_in(block, new_max, new_in);
			return;
		}
	}

	dbg_info  *dbgi         = get_irn_dbg_info(block);
	ir_node   *new_block    = new_rd_Block(dbgi, irg, new_max, new_in);
	ir_entity *block_entity = get_Block_entity(block);
	set_Block_entity(new_block, block_entity);

	/* 2. Remove inputs on Phis, where the block input is Bad. */
	for (ir_node *phi = get_Block_phis(block), *next; phi != NULL; phi = next) {
		next = get_Phi_next(phi);

		assert(get_irn_arity(phi) == max);

		unsigned j = 0;
		foreach_irn_in(phi, i, pred) {
			ir_node *const block_pred = get_Block_cfgpred(block, i);
			if (!is_Bad(block_pred)) {
				new_in[j++] = pred;
			}
		}
		assert(j == new_max);

		/* shortcut if only 1 phi input is left */
		if (new_max == 1) {
			ir_node *new_node = new_in[0];
			/* can happen inside unreachable endless loops */
			if (new_node == phi)
				return;
			if (get_Phi_loop(phi))
				remove_keep_alive(phi);
			exchange(phi, new_node);
		} else {
			set_irn_in(phi, new_max, new_in);
		}
	}
예제 #2
0
ir_node *be_complete_Phi(ir_node *const phi, unsigned const n_ins, ir_node **const ins)
{
	assert(is_Phi(phi) && get_Phi_n_preds(phi) == 0);

	ir_graph *const irg = get_irn_irg(phi);
	phi->attr.phi.u.backedge = new_backedge_arr(get_irg_obstack(irg), n_ins);
	set_irn_in(phi, n_ins, ins);

	arch_register_req_t const **const in_reqs = be_allocate_in_reqs(irg, n_ins);
	arch_register_req_t const  *const req     = arch_get_irn_register_req(phi);
	for (unsigned i = 0; i < n_ins; ++i) {
		in_reqs[i] = req;
	}
	backend_info_t *const info = be_get_info(phi);
	info->in_reqs = in_reqs;

	verify_new_node(phi);
	return phi;
}
예제 #3
0
/**
 * Computes the predecessors for the real phi node, and then
 * allocates and returns this node.  The routine called to allocate the
 * node might optimize it away and return a real value.
 * This function must be called with an in-array of proper size.
 */
static ir_node *set_phi_arguments(ir_node *phi, int pos)
{
	ir_node  *block        = get_nodes_block(phi);
	ir_graph *irg          = get_irn_irg(block);
	int       arity        = get_irn_arity(block);
	ir_node **in           = ALLOCAN(ir_node*, arity);
	ir_mode  *mode         = get_irn_mode(phi);

	/* This loop goes to all predecessor blocks of the block the Phi node
	 * is in and there finds the operands of the Phi node by calling
	 * get_r_value_internal.  */
	for (int i = 0; i < arity; ++i) {
		ir_node *cfgpred = get_Block_cfgpred_block(block, i);
		ir_node *value;
		if (cfgpred == NULL) {
			value = new_r_Bad(irg, mode);
		} else {
			value = get_r_value_internal(cfgpred, pos, mode);
		}
		in[i] = value;
	}

	phi->attr.phi.u.backedge = new_backedge_arr(get_irg_obstack(irg), arity);
	set_irn_in(phi, arity, in);

	verify_new_node(phi);

	try_remove_unnecessary_phi(phi);

	/* To solve the problem of (potentially) endless loops being observable
	 * behaviour we add a keep-alive edge too all PhiM nodes. */
	if (mode == mode_M && !is_Id(phi)) {
		phi->attr.phi.loop = true;
		keep_alive(phi);
	}

	return phi;
}
예제 #4
0
/**
 * lower 64bit conversions
 */
static void ia32_lower_conv64(ir_node *node, ir_mode *mode)
{
	dbg_info  *dbg       = get_irn_dbg_info(node);
	ir_node   *op        = get_Conv_op(node);
	ir_mode   *mode_from = get_irn_mode(op);
	ir_mode   *mode_to   = get_irn_mode(node);

	if (mode_is_float(mode_from) && get_mode_size_bits(mode_to) == 64
	    && get_mode_arithmetic(mode_to) == irma_twos_complement) {
		/* We have a Conv float -> long long here */
		ir_node *float_to_ll;
		ir_node *l_res;
		ir_node *h_res;
		if (mode_is_signed(mode)) {
			/* convert from float to signed 64bit */
			ir_node *block = get_nodes_block(node);
			float_to_ll = new_bd_ia32_l_FloattoLL(dbg, block, op);
			l_res = new_r_Proj(float_to_ll, ia32_mode_gp,
			                   pn_ia32_l_FloattoLL_res_low);
			h_res = new_r_Proj(float_to_ll, mode,
							   pn_ia32_l_FloattoLL_res_high);
		} else {
			/* Convert from float to unsigned 64bit. */
			ir_graph  *irg = get_irn_irg(node);
			ir_tarval *flt_tv
				= new_tarval_from_str("9223372036854775808", 19, x86_mode_E);
			ir_node   *flt_corr  = new_r_Const(irg, flt_tv);

			ir_node *lower_blk = part_block_dw(node);
			ir_node *upper_blk = get_nodes_block(node);
			set_dw_control_flow_changed();

			ir_node *opc  = new_rd_Conv(dbg, upper_blk, op, x86_mode_E);
			ir_node *cmp  = new_rd_Cmp(dbg, upper_blk, opc, flt_corr,
			                           ir_relation_less);
			ir_node *cond = new_rd_Cond(dbg, upper_blk, cmp);
			ir_node *in[] = {
				new_r_Proj(cond, mode_X, pn_Cond_true),
				new_r_Proj(cond, mode_X, pn_Cond_false)
			};
			ir_node *blk   = new_r_Block(irg, 1, &in[1]);
			in[1] = new_r_Jmp(blk);

			set_irn_in(lower_blk, 2, in);

			/* create to Phis */
			ir_node *phi_in[] = {
				new_r_Const_null(irg, mode),
				new_r_Const_long(irg, mode, 0x80000000)
			};
			ir_node *int_phi
				= new_r_Phi(lower_blk, ARRAY_SIZE(phi_in), phi_in, mode);

			ir_node *fphi_in[] = {
				opc,
				new_rd_Sub(dbg, upper_blk, opc, flt_corr, x86_mode_E)
			};
			ir_node *flt_phi
				= new_r_Phi(lower_blk, ARRAY_SIZE(fphi_in), fphi_in,
				            x86_mode_E);

			/* fix Phi links for next part_block() */
			if (is_Phi(int_phi))
				add_Block_phi(lower_blk, int_phi);
			if (is_Phi(flt_phi))
				add_Block_phi(lower_blk, flt_phi);

			float_to_ll = new_bd_ia32_l_FloattoLL(dbg, lower_blk, flt_phi);
			l_res = new_r_Proj(float_to_ll, ia32_mode_gp,
							   pn_ia32_l_FloattoLL_res_low);
			h_res = new_r_Proj(float_to_ll, mode,
							   pn_ia32_l_FloattoLL_res_high);
			h_res = new_rd_Add(dbg, lower_blk, h_res, int_phi, mode);

			/* move the call and its Proj's to the lower block */
			set_nodes_block(node, lower_blk);
			for (ir_node *proj = (ir_node*)get_irn_link(node); proj != NULL;
			     proj = (ir_node*)get_irn_link(proj)) {
				set_nodes_block(proj, lower_blk);
			}
		}
		ir_set_dw_lowered(node, l_res, h_res);
	} else if (get_mode_size_bits(mode_from) == 64
	           && get_mode_arithmetic(mode_from) == irma_twos_complement
	           && mode_is_float(mode_to)) {
		/* We have a Conv long long -> float here */
		ir_node *op_low  = get_lowered_low(op);
		ir_node *op_high = get_lowered_high(op);
		ir_node *block   = get_nodes_block(node);
		ir_node *ll_to_float
			= new_bd_ia32_l_LLtoFloat(dbg, block, op_high, op_low, mode_to);

		exchange(node, ll_to_float);
	} else {
		ir_default_lower_dw_Conv(node, mode);
	}
}
예제 #5
0
파일: return.c 프로젝트: qznc/libfirm
/*
 * Normalize the Returns of a graph by creating a new End block
 * with One Return(Phi).
 * This is the preferred input for the if-conversion.
 *
 * In pseudocode, it means:
 *
 * if (a)
 *   return b;
 * else
 *   return c;
 *
 * is transformed into
 *
 * if (a)
 *   res = b;
 * else
 *   res = c;
 * return res;
 */
void normalize_one_return(ir_graph *irg)
{
    ir_node   *endbl         = get_irg_end_block(irg);
    ir_entity *entity        = get_irg_entity(irg);
    ir_type   *type          = get_entity_type(entity);
    int        n_ret_vals    = get_method_n_ress(type) + 1;
    int        n_rets        = 0;
    bool       filter_dbgi   = false;
    dbg_info  *combined_dbgi = NULL;
    int i, j, k, n, last_idx;
    ir_node **in, **retvals, **endbl_in;
    ir_node *block;

    /* look, if we have more than one return */
    n = get_Block_n_cfgpreds(endbl);
    if (n <= 0) {
        /* The end block has no predecessors, we have an endless
           loop. In that case, no returns exists. */
        confirm_irg_properties(irg, IR_GRAPH_PROPERTIES_ALL);
        add_irg_properties(irg, IR_GRAPH_PROPERTY_ONE_RETURN);
        return;
    }

    unsigned *const returns = rbitset_alloca(n);
    for (i = 0; i < n; ++i) {
        ir_node *node = get_Block_cfgpred(endbl, i);

        if (is_Return(node)) {
            dbg_info *dbgi = get_irn_dbg_info(node);

            if (dbgi != NULL && dbgi != combined_dbgi) {
                if (filter_dbgi) {
                    combined_dbgi = NULL;
                } else {
                    combined_dbgi = dbgi;
                    filter_dbgi   = true;
                }
            }

            ++n_rets;
            rbitset_set(returns, i);
        }
    }

    if (n_rets <= 1) {
        confirm_irg_properties(irg, IR_GRAPH_PROPERTIES_ALL);
        add_irg_properties(irg, IR_GRAPH_PROPERTY_ONE_RETURN);
        return;
    }

    in       = ALLOCAN(ir_node*, MAX(n_rets, n_ret_vals));
    retvals  = ALLOCAN(ir_node*, n_rets * n_ret_vals);
    endbl_in = ALLOCAN(ir_node*, n);

    last_idx = 0;
    for (j = i = 0; i < n; ++i) {
        ir_node *ret = get_Block_cfgpred(endbl, i);

        if (rbitset_is_set(returns, i)) {
            ir_node *block = get_nodes_block(ret);

            /* create a new Jmp for every Ret and place the in in */
            in[j] = new_r_Jmp(block);

            /* save the return values and shuffle them */
            for (k = 0; k < n_ret_vals; ++k)
                retvals[j + k*n_rets] = get_irn_n(ret, k);

            ++j;
        } else {
            endbl_in[last_idx++] = ret;
        }
    }

    /* ok, create a new block with all created in's */
    block = new_r_Block(irg, n_rets, in);

    /* now create the Phi nodes */
    for (j = i = 0; i < n_ret_vals; ++i, j += n_rets) {
        ir_mode *mode = get_irn_mode(retvals[j]);
        in[i] = new_r_Phi(block, n_rets, &retvals[j], mode);
    }

    endbl_in[last_idx++] = new_rd_Return(combined_dbgi, block, in[0], n_ret_vals-1, &in[1]);

    set_irn_in(endbl, last_idx, endbl_in);

    /* invalidate analysis information:
     * a new Block was added, so dominator, outs and loop are inconsistent,
     * trouts and callee-state should be still valid */
    confirm_irg_properties(irg,
                           IR_GRAPH_PROPERTY_NO_BADS
                           | IR_GRAPH_PROPERTY_NO_TUPLES
                           | IR_GRAPH_PROPERTY_NO_CRITICAL_EDGES
                           | IR_GRAPH_PROPERTY_NO_UNREACHABLE_CODE
                           | IR_GRAPH_PROPERTY_CONSISTENT_ENTITY_USAGE);
    add_irg_properties(irg, IR_GRAPH_PROPERTY_ONE_RETURN);
}