14 DEBUG_ONLY(static firm_dbg_module_t *dbg);
16 static ir_node *search_def_and_create_phis(ir_node *block, ir_mode *mode) {
23 assert(!is_Bad(block));
25 // already processed this block?
26 if(irn_visited(block)) {
27 ir_node *value = (ir_node*) get_irn_link(block);
31 // blocks with only 1 pred need no phi
32 n_cfgpreds = get_Block_n_cfgpreds(block);
34 ir_node *pred_block = get_Block_cfgpred_block(block, 0);
35 ir_node *value = search_def_and_create_phis(pred_block, mode);
37 set_irn_link(block, value);
38 mark_irn_visited(block);
43 in = alloca(sizeof(in[0]) * n_cfgpreds);
44 for(i = 0; i < n_cfgpreds; ++i)
45 in[i] = new_Unknown(mode);
47 irg = get_irn_irg(block);
48 phi = new_r_Phi(irg, block, n_cfgpreds, in, mode);
49 set_irn_link(block, phi);
50 mark_irn_visited(block);
53 for(i = 0; i < n_cfgpreds; ++i) {
54 ir_node *pred_block = get_Block_cfgpred_block(block, i);
57 pred_val = search_def_and_create_phis(pred_block, mode);
58 set_irn_n(phi, i, pred_val);
65 * Given a set of values this function constructs SSA-form for all users of the
66 * values (the user are determined through the out-edges of the values).
68 static void construct_ssa(ir_node * const *vals, int n_vals) {
75 irg = get_irn_irg(vals[0]);
78 mode = get_irn_mode(vals[0]);
79 for(i = 0; i < n_vals; ++i) {
80 ir_node *value = vals[i];
81 ir_node *value_block = get_nodes_block(value);
83 assert(get_irn_mode(value) == mode);
85 set_irn_link(value_block, value);
86 mark_irn_visited(value_block);
89 for(i = 0; i < n_vals; ++i) {
90 const ir_edge_t *edge;
91 ir_node *value = vals[i];
93 foreach_out_edge(value, edge) {
94 ir_node *user = get_edge_src_irn(edge);
95 ir_node *user_block = get_nodes_block(user);
98 newval = search_def_and_create_phis(user_block, mode);
99 set_irn_n(user, get_edge_src_pos(edge), newval);
107 static void cond_eval(ir_node* block, void* env)
109 int n_block = get_Block_n_cfgpreds(block);
112 for (i = 0; i < n_block; i++) {
127 pred = get_Block_cfgpred(block, i);
128 if (!is_Proj(pred)) continue;
131 pred = get_Proj_pred(projx);
132 if (!is_Cond(pred)) continue;
135 pred = get_Cond_selector(cond);
136 assert(is_Proj(pred));
137 // TODO handle switches
138 if (get_irn_mode(pred) != mode_b) continue;
139 pnc = get_Proj_proj(pred);
141 cmp = get_Proj_pred(pred);
144 left = get_Cmp_left(cmp);
145 right = get_Cmp_right(cmp);
147 // TODO handle Const-Const and Phi-Phi
149 if (!is_Const(right)) continue;
152 } else if (is_Phi(right)) {
153 if (!is_Const(left)) continue;
156 pnc = get_inversed_pnc(pnc);
160 tv_cnst = get_Const_tarval(cnst);
162 cond_block = get_nodes_block(cond);
163 if (get_nodes_block(phi) != cond_block) continue;
165 if (get_Proj_proj(projx) == 0) {
166 pnc = get_negated_pnc(pnc, get_irn_mode(cnst));
169 n_phi = get_Phi_n_preds(phi);
170 for (j = 0; j < n_phi; j++) {
176 pred = get_Phi_pred(phi, j);
177 // TODO handle Phi cascades
178 if (!is_Const(pred)) continue;
180 tv_phi = get_Const_tarval(pred);
182 cmp_val = tarval_cmp(tv_phi, tv_cnst);
183 if (cmp_val == pn_Cmp_False)
185 if ((cmp_val & pnc) != cmp_val)
190 "> Found condition evaluation candidate %+F->%+F predecessor %d\n",
194 #if 0 // TODO repair data flow and dominance
195 NEW_ARR_A(ir_node*, ins, n_block + 1);
196 for (k = 0; k < n_block; k++) ins[k] = get_Block_cfgpred(block, k);
197 ins[k] = get_Block_cfgpred(cond_block, j);
198 set_irn_in(block, n_block + 1, ins);
200 set_Block_cfgpred(cond_block, j, new_Bad());
201 set_Phi_pred(phi, j, new_Bad());
208 void opt_cond_eval(ir_graph* irg)
210 FIRM_DBG_REGISTER(dbg, "firm.opt.condeval");
211 firm_dbg_set_mask(dbg, SET_LEVEL_5);
213 DB((dbg, LEVEL_1, "===> Performing condition evaluation on %+F\n", irg));
215 irg_block_walk_graph(irg, NULL, cond_eval, NULL);