2 * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @brief Support for ir graph modification.
23 * @author Martin Trapp, Christian Schaefer, Goetz Lindenmaier
34 #include "irgraph_t.h"
39 #include "iredges_t.h"
44 * Turns a node into a "useless" Tuple. The Tuple just forms a tuple
45 * from several inputs.
46 * This is useful if a node returning a tuple is removed, but the Projs
47 * extracting values from the tuple are not available.
49 void turn_into_tuple(ir_node *node, int arity) {
51 set_irn_op(node, op_Tuple);
52 if (get_irn_arity(node) == arity) {
55 ir_node *block = get_nodes_block(node);
56 /* Allocate new array, don't free old in_array, it's on the obstack. */
57 edges_node_deleted(node, current_ir_graph);
58 node->in = NEW_ARR_D(ir_node *, current_ir_graph->obst, arity+1);
59 /* clear the new in array, else edge_notify tries to delete garbage */
60 memset(node->in, 0, (arity+1) * sizeof(node->in[0]));
61 set_nodes_block(node, block);
66 * Insert irnode `new' in place of irnode `old'
67 * Since `new' may be bigger than `old' replace `old'
68 * by an op_Id which is smaller than everything.
70 void exchange(ir_node *old, ir_node *nw) {
74 assert(old != nw && "Exchanging node with itself is not allowed");
76 irg = get_irn_irg(old);
77 assert(irg == get_irn_irg(nw) && "New node must be in same irg as old node");
79 hook_replace(old, nw);
82 * If new outs are on, we can skip the id node creation and reroute
83 * the edges from the old node to the new directly.
85 if (edges_activated(irg)) {
86 /* copy all dependencies from old to new */
87 add_irn_deps(nw, old);
89 edges_reroute(old, nw, irg);
90 edges_reroute_kind(old, nw, EDGE_KIND_DEP, irg);
91 edges_node_deleted(old, irg);
94 /* Else, do it the old-fashioned way. */
97 assert(get_irn_op(old)->opar != oparity_dynamic);
99 hook_turn_into_id(old);
103 block = is_Block(nw) ? nw : get_nodes_block(nw);
106 panic("cannot find legal block for id");
111 old->in = NEW_ARR_D (ir_node *, irg->obst, 2);
117 /*--------------------------------------------------------------------*/
118 /* Functionality for collect_phis */
119 /*--------------------------------------------------------------------*/
122 * Walker: links all Phi nodes to their Blocks and
123 * all Proj nodes to there predecessors
125 static void collect(ir_node *n, void *env) {
130 set_irn_link(n, get_irn_link(get_nodes_block(n)));
131 set_irn_link(get_nodes_block(n), n);
132 } else if (is_Proj(n)) {
135 pred = get_Proj_pred(pred);
136 } while (is_Proj(pred));
138 set_irn_link(n, get_irn_link(pred));
139 set_irn_link(pred, n);
143 void collect_phiprojs(ir_graph *irg) {
144 irg_walk_graph(irg, firm_clear_link, collect, NULL);
148 /*--------------------------------------------------------------------*/
149 /* Functionality for part_block */
150 /*--------------------------------------------------------------------*/
153 * Moves node and all predecessors of node from from_bl to to_bl.
154 * Does not move predecessors of Phi nodes (or block nodes).
156 static void move(ir_node *node, ir_node *from_bl, ir_node *to_bl) {
158 ir_node *proj, *pred;
161 set_nodes_block(node, to_bl);
164 if (get_irn_mode(node) == mode_T) {
165 proj = get_irn_link(node);
167 if (get_nodes_block(proj) == from_bl)
168 set_nodes_block(proj, to_bl);
169 proj = get_irn_link(proj);
174 if (get_irn_op(node) == op_Phi) return;
176 arity = get_irn_arity(node);
177 for (i = 0; i < arity; i++) {
178 pred = get_irn_n(node, i);
179 if (get_nodes_block(pred) == from_bl)
180 move(pred, from_bl, to_bl);
184 void part_block(ir_node *node) {
189 /* Turn off optimizations so that blocks are not merged again. */
190 int rem_opt = get_opt_optimize();
193 /* Transform the control flow */
194 old_block = get_nodes_block(node);
195 new_block = new_Block(get_Block_n_cfgpreds(old_block),
196 get_Block_cfgpred_arr(old_block));
197 set_irg_current_block(current_ir_graph, new_block);
199 ir_node *jmp = new_Jmp();
200 set_irn_in(old_block, 1, &jmp);
201 irn_vrfy_irg(old_block, current_ir_graph);
204 /* move node and its predecessors to new_block */
205 move(node, old_block, new_block);
207 /* move Phi nodes to new_block */
208 phi = get_irn_link(old_block);
209 set_irn_link(new_block, phi);
210 set_irn_link(old_block, NULL);
212 set_nodes_block(phi, new_block);
213 phi = get_irn_link(phi);
216 set_optimize(rem_opt);
219 /* kill a node by setting its predecessors to Bad and finally exchange the node by Bad itself. */
220 void kill_node(ir_node *node) {
221 ir_graph *irg = get_irn_irg(node);
222 ir_node *bad = get_irg_bad(irg);
225 for (i = get_irn_arity(node) - 1; i >= -1; --i) {
226 set_irn_n(node, i, bad);