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 Perform optimizations of the type representation.
24 * @author Goetz Lindenmaier
38 #include "tr_inheritance.h"
39 #include "irtypeinfo.h"
41 #include "irsimpletype.h"
48 /* - statistics ---------------------------------------------- */
50 static int n_casts_normalized = 0;
51 static int n_casts_removed = 0;
52 static int n_sels_concretized = 0;
54 /* - Cast normalization. ------------------------------------- */
56 static ir_type *default_gen_pointer_type_to(ir_type *tp);
58 #define PTR_TYPE_SUFFIX "cc_ptr_tp" /* class cast pointer type. */
59 static ident *ptr_type_suffix = NULL;
60 static gen_pointer_type_to_func gen_pointer_type_to = default_gen_pointer_type_to;
63 * Find a pointer type to a given type.
64 * Uses and updates trouts if available.
66 static ir_type *default_gen_pointer_type_to(ir_type *tp) {
68 if (get_trouts_state() == outs_consistent) {
69 if (get_type_n_pointertypes_to(tp) > 0) {
70 res = get_type_pointertype_to(tp, 0);
72 ir_mode *mode = is_Method_type(tp) ? mode_P_code : mode_P_data;
74 res = new_type_pointer(mangle_u(get_type_ident(tp), ptr_type_suffix), tp, mode);
75 /* Update trout for pointer types, so we can use it in next call. */
76 add_type_pointertype_to(tp, res);
80 res = find_pointer_type_to_type(tp);
81 if (res == firm_unknown_type)
82 res = new_type_pointer(mangle_u(get_type_ident(tp), ptr_type_suffix), tp, mode_P_data);
88 /** Return a type that is a depth times pointer to type. */
89 static ir_type *pointerize_type(ir_type *tp, int depth) {
90 for (; depth > 0; --depth) {
91 tp = gen_pointer_type_to(tp);
97 static ir_node *normalize_values_type(ir_type *totype, ir_node *pred) {
98 ir_type *fromtype = get_irn_typeinfo_type(pred);
99 ir_node *new_cast = pred;
102 if (totype == fromtype) return pred; /* Case for optimization! */
104 while (is_Pointer_type(totype) && is_Pointer_type(fromtype)) {
105 totype = get_pointer_points_to_type(totype);
106 fromtype = get_pointer_points_to_type(fromtype);
110 if (!is_Class_type(totype)) return pred;
111 if (!is_Class_type(fromtype)) return pred;
113 if ((get_class_supertype_index(totype, fromtype) != -1) ||
114 (get_class_supertype_index(fromtype, totype) != -1) ) {
115 /* It's just what we want ... */
119 set_cur_block(get_nodes_block(pred));
121 if (is_SubClass_of(totype, fromtype)) {
123 while (get_class_subtype_index(fromtype, totype) == -1) {
124 /* Insert a cast to a subtype of fromtype. */
125 ir_type *new_type = NULL;
127 int i, n_subtypes = get_class_n_subtypes(fromtype);
128 for (i = 0; i < n_subtypes && !new_type; ++i) {
129 ir_type *new_sub = get_class_subtype(fromtype, i);
130 if (is_SuperClass_of(new_sub, totype))
135 new_type = pointerize_type(new_type, ref_depth);
136 new_cast = new_Cast(pred, new_type);
138 n_casts_normalized ++;
139 set_irn_typeinfo_type(new_cast, new_type); /* keep type information up to date. */
140 if (get_trouts_state() != outs_none) add_type_cast(new_type, new_cast);
144 assert(is_SuperClass_of(totype, fromtype));
146 while (get_class_supertype_index(fromtype, totype) == -1) {
147 /* Insert a cast to a supertype of fromtype. */
148 ir_type *new_type = NULL;
149 int i, n_supertypes = get_class_n_supertypes(fromtype);
150 for (i = 0; i < n_supertypes && !new_type; ++i) {
151 ir_type *new_super = get_class_supertype(fromtype, i);
152 if (is_SubClass_of(new_super, totype))
153 new_type = new_super;
157 new_type = pointerize_type(new_type, ref_depth);
158 new_cast = new_Cast(pred, new_type);
160 n_casts_normalized ++;
161 set_irn_typeinfo_type(new_cast, new_type); /* keep type information up to date. */
162 if (get_trouts_state() != outs_none) add_type_cast(new_type, new_cast);
169 static void normalize_irn_class_cast(ir_node *n, void *env) {
171 if (get_irn_op(n) == op_Cast) {
172 ir_node *pred = get_Cast_op(n);
173 ir_type *totype = get_Cast_type(n);
174 res = normalize_values_type(totype, pred);
176 } else if (get_irn_op(n) == op_Call) {
177 int i, n_params = get_Call_n_params(n);
178 ir_type *tp = get_Call_type(n);
179 for (i = 0; i < n_params; ++i) {
180 res = normalize_values_type(get_method_param_type(tp, i), get_Call_param(n, i));
181 set_Call_param(n, i, res);
187 static void pure_normalize_irg_class_casts(ir_graph *irg) {
188 assert(get_irg_class_cast_state(irg) != ir_class_casts_any &&
189 "Cannot normalize irregular casts.");
190 if (get_irg_class_cast_state(irg) == ir_class_casts_normalized) {
191 verify_irg_class_cast_state(irg);
195 irg_walk_graph(irg, NULL, normalize_irn_class_cast, NULL);
196 set_irg_class_cast_state(irg, ir_class_casts_normalized);
200 void normalize_irg_class_casts(ir_graph *irg, gen_pointer_type_to_func gppt_fct) {
201 assert(get_irp_typeinfo_state() == ir_typeinfo_consistent);
203 if (gppt_fct) gen_pointer_type_to = gppt_fct;
205 if (!ptr_type_suffix)
206 ptr_type_suffix = new_id_from_str(PTR_TYPE_SUFFIX);
208 pure_normalize_irg_class_casts(irg);
210 gen_pointer_type_to = default_gen_pointer_type_to;
213 void normalize_irp_class_casts(gen_pointer_type_to_func gppt_fct) {
214 int i, n_irgs = get_irp_n_irgs();
215 if (gppt_fct) gen_pointer_type_to = gppt_fct;
217 if (get_irp_typeinfo_state() != ir_typeinfo_consistent)
218 simple_analyse_types();
220 for (i = 0; i < n_irgs; ++i) {
221 pure_normalize_irg_class_casts(get_irp_irg(i));
224 set_irp_class_cast_state(ir_class_casts_normalized);
225 gen_pointer_type_to = default_gen_pointer_type_to;
227 if (get_opt_optimize_class_casts_verbose() && get_firm_verbosity()) {
228 printf(" Cast normalization: %d Casts inserted.\n", n_casts_normalized);
234 /* - Cast optimization. ------------------------------------------- */
239 * (T1)(T2)x<T1> -> x<T1>
241 * (T3)(T2)x<T1> -> (T3)x<T1>
245 static void cancel_out_casts(ir_node *cast) {
246 ir_node *orig, *pred = get_Cast_op(cast);
247 ir_type *tp_cast, *tp_pred, *tp_orig;
250 if (get_irn_op(pred) != op_Cast) return;
251 orig = get_Cast_op(pred);
253 tp_cast = get_Cast_type(cast);
254 tp_pred = get_Cast_type(pred);
255 tp_orig = get_irn_typeinfo_type(orig);
257 while (is_Pointer_type(tp_cast) &&
258 is_Pointer_type(tp_pred) &&
259 is_Pointer_type(tp_orig) ) {
260 tp_cast = get_pointer_points_to_type(tp_cast);
261 tp_pred = get_pointer_points_to_type(tp_pred);
262 tp_orig = get_pointer_points_to_type(tp_orig);
266 if (!is_Class_type(tp_cast)) return;
267 if (!is_Class_type(tp_pred)) return;
268 if (!is_Class_type(tp_orig)) return;
270 if (is_SubClass_of(tp_pred, tp_cast) && get_opt_suppress_downcast_optimization())
273 if (tp_cast == tp_orig) {
274 exchange(cast, orig);
275 n_casts_removed += 2;
279 if (!(is_SubClass_of (tp_cast, tp_orig) || is_SubClass_of (tp_orig, tp_cast))) {
280 /* Avoid (B2)(A)(new B1()) --> (B2)(new B1())
281 * if B1 =!> B2 and B2 =!> B1
286 if ((is_SubClass_of (tp_cast, tp_pred) && is_SuperClass_of(tp_pred, tp_orig)) ||
287 (is_SuperClass_of(tp_cast, tp_pred) && is_SubClass_of (tp_pred, tp_orig)) ) {
288 /* Cast --> Pred --> Orig */
289 set_Cast_op (cast, orig);
294 static void concretize_selected_entity(ir_node *sel) {
295 ir_node *cast, *ptr = get_Sel_ptr(sel);
296 ir_type *orig_tp, *cast_tp;
297 ir_entity *new_ent, *sel_ent;
299 sel_ent = get_Sel_entity(sel);
300 cast = get_Sel_ptr(sel);
302 while (get_irn_op(cast) == op_Cast) {
303 cast_tp = get_Cast_type(cast);
304 ptr = get_Cast_op(cast);
305 orig_tp = get_irn_typeinfo_type(ptr);
307 if (!is_Pointer_type(orig_tp)) return;
308 if (!is_Pointer_type(cast_tp)) return;
309 orig_tp = get_pointer_points_to_type(orig_tp);
310 cast_tp = get_pointer_points_to_type(cast_tp);
311 if (!is_Class_type(orig_tp)) return;
312 if (!is_Class_type(cast_tp)) return;
314 /* We only want to concretize, but not generalize. */
315 if (!is_SuperClass_of(cast_tp, orig_tp)) return;
317 /* Hmm, we are not properly typed. */
318 if (get_class_member_index(cast_tp, sel_ent) == -1) return;
320 new_ent = resolve_ent_polymorphy(orig_tp, sel_ent);
322 /* New ent must be member of orig_tp. */
323 if (get_class_member_index(orig_tp, new_ent) == -1) return;
325 set_Sel_entity(sel, new_ent);
326 set_Sel_ptr(sel, ptr);
327 n_sels_concretized++;
334 static void concretize_Phi_type(ir_node *phi) {
335 int i, n_preds = get_Phi_n_preds(phi);
336 ir_node **pred = alloca(n_preds * sizeof(ir_node *));
338 ir_type *totype, *fromtype;
340 if (n_preds == 0) return;
341 pred[0] = get_Phi_pred(phi, 0);
343 if (get_irn_op(pred[0]) != op_Cast) return;
345 if (!is_Cast_upcast(pred[0])) return;
347 fromtype = get_irn_typeinfo_type(get_Cast_op(pred[0]));
348 totype = get_Cast_type(pred[0]);
350 pred[0] = get_Cast_op(pred[0]);
351 for (i = 1; i < n_preds; ++i) {
352 pred[i] = get_Phi_pred(phi, i);
353 if (get_irn_op(pred[i]) != op_Cast) return;
354 if (get_irn_typeinfo_type(get_Cast_op(pred[i])) != fromtype) return;
355 pred[i] = get_Cast_op(pred[i]);
359 set_cur_block(get_nodes_block(phi));
360 new = new_Phi(n_preds, pred, get_irn_mode(phi));
361 set_irn_typeinfo_type(new, fromtype);
362 new = new_Cast(new, totype);
363 set_irn_typeinfo_type(new, totype);
367 void remove_Cmp_Null_cast(ir_node *cmp) {
368 ir_node *cast, *null, *new_null;
369 int cast_pos, null_pos;
372 cast = get_Cmp_left(cmp);
374 if (get_irn_op(cast) != op_Cast) {
377 cast = get_Cmp_right(cmp);
379 if (get_irn_op(cast) != op_Cast) return;
381 null = get_Cmp_right(cmp);
385 if (get_irn_op(null) != op_Const) return;
386 if (!mode_is_reference(get_irn_mode(null))) return;
387 if (get_Const_tarval(null) != get_mode_null(get_irn_mode(null))) return;
390 set_irn_n(cmp, cast_pos, get_Cast_op(cast));
391 fromtype = get_irn_typeinfo_type(get_Cast_op(cast));
392 new_null = new_Const_type(get_Const_tarval(null), fromtype);
393 set_irn_typeinfo_type(new_null, fromtype);
394 set_irn_n(cmp, null_pos, new_null);
401 static void irn_optimize_class_cast(ir_node *n, void *env) {
402 if (get_irn_op(n) == op_Cast)
404 else if (get_irn_op(n) == op_Sel)
405 concretize_selected_entity(n);
406 else if (get_irn_op(n) == op_Phi)
407 concretize_Phi_type(n);
408 else if (get_irn_op(n) == op_Cmp)
409 remove_Cmp_Null_cast(n);
412 void optimize_class_casts(void) {
413 int i, n_irgs = get_irp_n_irgs();
415 if (get_irp_typeinfo_state() != ir_typeinfo_consistent)
416 simple_analyse_types();
418 all_irg_walk(NULL, irn_optimize_class_cast, NULL);
420 set_trouts_inconsistent();
421 for (i = 0; i < n_irgs; ++i)
422 set_irg_outs_inconsistent(get_irp_irg(i));
424 if (get_opt_optimize_class_casts_verbose() && get_firm_verbosity()) {
425 printf(" Cast optimization: %d Casts removed, %d Sels concretized.\n",
426 n_casts_removed, n_sels_concretized);