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4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
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9 * packaging of this file.
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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 restarting SSA construction for values.
23 * @author Michael Beck
29 #include "irgraph_t.h"
34 * Post-walker: prepare the graph nodes for new SSA construction cycle by
35 * allocation new arrays.
37 static void prepare_blocks(ir_node *irn, void *env)
40 unsigned n_loc = current_ir_graph->n_loc;
41 struct obstack *obst = current_ir_graph->obst;
42 /* reset mature flag */
43 set_Block_matured(irn, 0);
44 irn->attr.block.graph_arr = NEW_ARR_D(ir_node *, obst, n_loc);
45 memset(irn->attr.block.graph_arr, 0, sizeof(ir_node*) * n_loc);
46 irn->attr.block.phis = NULL;
50 * Restarts SSA construction on the given graph with n_loc
53 * @param irg the graph on which the SSA construction is restarted
54 * @param n_loc number of new variables
56 * After this function is complete, the graph is in phase_building
57 * again and set_value()/get_value() and mature_block() can be used
58 * to construct new values.
60 void ssa_cons_start(ir_graph *irg, int n_loc)
62 /* for now we support only phase_high graphs */
63 assert(irg->phase_state == phase_high);
65 /* reset the phase to phase building: some optimization might depend on it */
66 set_irg_phase_state(irg, phase_building);
68 irg_set_nloc(irg, n_loc);
71 * Note: we could try to reuse existing frag arrays, but it does not
72 * seems worth to do this. First, we have to check if they really exists and
73 * then clear them. We do not expect SSA construction is used often.
75 irg_block_walk_graph(irg, NULL, prepare_blocks, NULL);
79 * mature all immature Blocks.
81 static void finish_block(ir_node *block, void *env)
85 if (!get_Block_matured(block))
86 mature_immBlock(block);
90 * Finalize the (restarted) SSA construction. Matures all blocks that are
91 * not matured yet and reset the graph state to phase_high.
93 void ssa_cons_finish(ir_graph *irg)
95 irg_block_walk_graph(irg, NULL, finish_block, NULL);
96 irg_finalize_cons(irg);