2 * Copyright (C) 1995-2008 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 read/write analyze of graph argument, which have mode reference.
23 * @author Beyhan Veliev
42 #include "analyze_irg_args.h"
45 static void *VISITED = &v;
48 * Walk recursive the successors of a graph argument
49 * with mode reference and mark if it will be read,
52 * @param arg The graph argument with mode reference,
53 * that must be checked.
55 static unsigned analyze_arg(ir_node *arg, unsigned bits) {
59 /* We must visit a node once to avoid endless recursion.*/
60 set_irn_link(arg, VISITED);
62 for (i = get_irn_n_outs(arg) - 1; i >= 0; --i) {
63 succ = get_irn_out(arg, i);
66 if (get_irn_link(succ) == VISITED)
69 /* We should not walk over the memory edge.*/
70 if (get_irn_mode(succ) == mode_M)
73 /* If we reach with the recursion a Call node and our reference
74 isn't the address of this Call we accept that the reference will
75 be read and written if the graph of the method represented by
76 "Call" isn't computed else we analyze that graph. If our
77 reference is the address of this
78 Call node that mean the reference will be read.*/
79 switch (get_irn_opcode(succ)) {
82 ir_node *ptr = get_Call_ptr(succ);
85 /* Hmm: not sure what this is, most likely a read */
86 bits |= ptr_access_read;
91 meth_ent = get_Global_entity(ptr);
93 for (p = get_Call_n_params(succ) - 1; p >= 0; --p) {
94 if (get_Call_param(succ, p) == arg) {
95 /* an arg can be used more than once ! */
96 bits |= get_method_param_access(meth_ent, p);
99 } else if (is_Sel(ptr) && get_irp_callee_info_state() == irg_callee_info_consistent) {
100 /* is be a polymorphic call but callee information is available */
101 int i, n_params = get_Call_n_params(succ);
103 /* simply look into ALL possible callees */
104 for (i = get_Call_n_callees(succ) - 1; i >= 0; --i) {
105 meth_ent = get_Call_callee(succ, i);
107 /* unknown_entity is used to signal that we don't know what is called */
108 if (meth_ent == unknown_entity) {
109 bits |= ptr_access_all;
113 for (p = n_params - 1; p >= 0; --p) {
114 if (get_Call_param(succ, p) == arg) {
115 /* an arg can be used more than once ! */
116 bits |= get_method_param_access(meth_ent, p);
120 } else /* can do anything */
121 bits |= ptr_access_all;
124 /* search stops here anyway */
128 /* We have reached a Store node => the reference is written or stored. */
129 if (get_Store_ptr(succ) == arg) {
131 bits |= ptr_access_write;
134 bits |= ptr_access_store;
137 /* search stops here anyway */
141 /* We have reached a Load node => the reference is read. */
142 bits |= ptr_access_read;
144 /* search stops here anyway */
148 /* our address is casted into something unknown. Break our search. */
149 bits = ptr_access_all;
156 /* If we know that, the argument will be read, write and stored, we
157 can break the recursion.*/
158 if (bits == ptr_access_all) {
159 bits = ptr_access_all;
164 * A calculation that do not lead to a reference mode ends our search.
165 * This is dangerous: It would allow to cast into integer and that cast back ...
166 * so, when we detect a Conv we go mad, see the Conv case above.
168 if (!mode_is_reference(get_irn_mode(succ)))
171 /* follow further the address calculation */
172 bits = analyze_arg(succ, bits);
174 set_irn_link(arg, NULL);
179 * Check if a argument of the ir graph with mode
180 * reference is read, write or both.
182 * @param irg The ir graph to analyze.
184 static void analyze_ent_args(ir_entity *ent) {
186 ir_node *irg_args, *arg;
191 ptr_access_kind *rw_info;
193 mtp = get_entity_type(ent);
194 nparams = get_method_n_params(mtp);
196 ent->attr.mtd_attr.param_access = NEW_ARR_F(ptr_access_kind, nparams);
198 /* If the method haven't parameters we have
204 irg = get_entity_irg(ent);
206 /* we have not yet analyzed the graph, set ALL access for pointer args */
207 for (i = nparams - 1; i >= 0; --i) {
208 ir_type *type = get_method_param_type(mtp, i);
209 ent->attr.mtd_attr.param_access[i] = is_Pointer_type(type) ? ptr_access_all : ptr_access_none;
213 /* no graph, no better info */
217 assure_irg_outs(irg);
219 irg_args = get_irg_args(irg);
221 /* A array to save the information for each argument with
223 NEW_ARR_A(ptr_access_kind, rw_info, nparams);
225 /* We initialize the element with none state. */
226 for (i = nparams - 1; i >= 0; --i)
227 rw_info[i] = ptr_access_none;
229 /* search for arguments with mode reference
231 for (i = get_irn_n_outs(irg_args) - 1; i >= 0; --i) {
232 arg = get_irn_out(irg_args, i);
233 arg_mode = get_irn_mode(arg);
234 proj_nr = get_Proj_proj(arg);
236 if (mode_is_reference(arg_mode))
237 rw_info[proj_nr] |= analyze_arg(arg, rw_info[proj_nr]);
240 /* copy the temporary info */
241 memcpy(ent->attr.mtd_attr.param_access, rw_info,
242 nparams * sizeof(ent->attr.mtd_attr.param_access[0]));
245 printf("\n%s:\n", get_entity_name(ent));
246 for (i = 0; i < nparams; ++i) {
247 if (is_Pointer_type(get_method_param_type(mtp, i)))
248 if (ent->attr.mtd_attr.param_access[i] != ptr_access_none) {
249 printf(" Pointer Arg %d access: ", i);
250 if (ent->attr.mtd_attr.param_access[i] & ptr_access_read)
252 if (ent->attr.mtd_attr.param_access[i] & ptr_access_write)
254 if (ent->attr.mtd_attr.param_access[i] & ptr_access_store)
263 * Analyze how pointer arguments of a given
264 * ir graph are accessed.
266 * @param irg The ir graph to analyze.
268 void analyze_irg_args(ir_graph *irg) {
271 if (irg == get_const_code_irg())
274 ent = get_irg_entity(irg);
278 if (! ent->attr.mtd_attr.param_access)
279 analyze_ent_args(ent);
283 * Compute for a method with pointer parameter(s)
284 * if they will be read or written.
286 ptr_access_kind get_method_param_access(ir_entity *ent, int pos)
289 ir_type *mtp = get_entity_type(ent);
290 int is_variadic = get_method_variadicity(mtp) == variadicity_variadic;
292 assert(0 <= pos && (is_variadic || pos < get_method_n_params(mtp)));
295 if (ent->attr.mtd_attr.param_access) {
296 if (pos < ARR_LEN(ent->attr.mtd_attr.param_access))
297 return ent->attr.mtd_attr.param_access[pos];
299 return ptr_access_all;
302 analyze_ent_args(ent);
304 if (pos < ARR_LEN(ent->attr.mtd_attr.param_access))
305 return ent->attr.mtd_attr.param_access[pos];
307 return ptr_access_all;
310 /* Weights for parameters */
312 null_weight = 0, /**< If can't be anything optimized. */
313 binop_weight = 1, /**< If the argument have mode_weight and take part in binop. */
314 const_binop_weight = 1, /**< If the argument have mode_weight and take part in binop with a constant.*/
315 cmp_weight = 4, /**< If the argument take part in cmp. */
316 const_cmp_weight = 10, /**< If the argument take part in cmp with a constant. */
317 indirect_call_weight = 125, /**< If the argument is the address of an indirect Call. */
321 * Compute the weight of a method parameter
323 * @param arg The parameter them weight muss be computed.
325 static unsigned calc_method_param_weight(ir_node *arg) {
328 unsigned weight = null_weight;
330 /* We mark the nodes to avoid endless recursion */
331 set_irn_link(arg, VISITED);
333 for (i = get_irn_n_outs(arg) - 1; i >= 0; i--) {
334 succ = get_irn_out(arg, i);
337 if (get_irn_link(succ) == VISITED)
340 /* We should not walk over the memory edge.*/
341 if (get_irn_mode(succ) == mode_M)
344 switch (get_irn_opcode(succ)) {
346 if (get_Call_ptr(succ) == arg) {
347 /* the arguments is used as an pointer input for a call,
348 we can probably change an indirect Call into a direct one. */
349 weight += indirect_call_weight;
353 /* We have reached a cmp and we must increase the
354 weight with the cmp_weight. */
355 if (get_Cmp_left(succ) == arg)
356 op = get_Cmp_right(succ);
358 op = get_Cmp_left(succ);
360 if (is_irn_constlike(op)) {
361 weight += const_cmp_weight;
363 weight += cmp_weight;
366 /* the argument is used for a SwitchCond, a big win */
367 weight += const_cmp_weight * get_irn_n_outs(succ);
370 /* when looking backward we might find Id nodes */
371 weight += calc_method_param_weight(succ);
374 /* unoptimized tuple */
375 for (j = get_Tuple_n_preds(succ) - 1; j >= 0; --j) {
376 ir_node *pred = get_Tuple_pred(succ, j);
378 /* look for Proj(j) */
379 for (k = get_irn_n_outs(succ) - 1; k >= 0; --k) {
380 ir_node *succ_succ = get_irn_out(succ, k);
381 if (is_Proj(succ_succ)) {
382 if (get_Proj_proj(succ_succ) == j) {
384 weight += calc_method_param_weight(succ_succ);
387 /* this should NOT happen */
394 if (is_binop(succ)) {
395 /* We have reached a BinOp and we must increase the
396 weight with the binop_weight. If the other operand of the
397 BinOp is a constant we increase the weight with const_binop_weight
398 and call the function recursive.
400 if (get_binop_left(succ) == arg)
401 op = get_binop_right(succ);
403 op = get_binop_left(succ);
405 if (is_irn_constlike(op)) {
406 weight += const_binop_weight;
407 weight += calc_method_param_weight(succ);
409 weight += binop_weight;
410 } else if (is_unop(succ)) {
411 /* We have reached a binop and we must increase the
412 weight with the const_binop_weight and call the function recursive.*/
413 weight += const_binop_weight;
414 weight += calc_method_param_weight(succ);
419 set_irn_link(arg, NULL);
424 * Calculate a weight for each argument of an entity.
426 * @param ent The entity of the ir_graph.
428 static void analyze_method_params_weight(ir_entity *ent) {
431 int nparams, i, proj_nr;
432 ir_node *irg_args, *arg;
434 mtp = get_entity_type(ent);
435 nparams = get_method_n_params(mtp);
437 /* allocate a new array. currently used as 'analysed' flag */
438 ent->attr.mtd_attr.param_weight = NEW_ARR_F(unsigned, nparams);
440 /* If the method haven't parameters we have nothing to do. */
444 /* First we initialize the parameter weights with 0. */
445 for (i = nparams - 1; i >= 0; i--)
446 ent->attr.mtd_attr.param_weight[i] = null_weight;
448 irg = get_entity_irg(ent);
450 /* no graph, no better info */
454 /* Call algorithm that computes the out edges */
455 assure_irg_outs(irg);
457 irg_args = get_irg_args(irg);
458 for (i = get_irn_n_outs(irg_args) - 1; i >= 0; --i) {
459 arg = get_irn_out(irg_args, i);
460 proj_nr = get_Proj_proj(arg);
461 ent->attr.mtd_attr.param_weight[proj_nr] += calc_method_param_weight(arg);
465 printf("\n%s:\n", get_entity_name(ent));
466 for (i = nparams - 1; i >= 0; --i)
467 printf("The weight of argument %i is %f \n", i, ent->param_weight[i]);
472 * Returns for a method the 'weight' that every parameter
473 * has on optimization possibility. Higher values allows
474 * higher optimization with procedure cloning.
476 * The values are calculation on demand only.
478 unsigned get_method_param_weight(ir_entity *ent, int pos)
481 ir_type *mtp = get_entity_type(ent);
482 int is_variadic = get_method_variadicity(mtp) == variadicity_variadic;
483 assert(0 <= pos && (is_variadic || pos < get_method_n_params(mtp)));
486 if (ent->attr.mtd_attr.param_weight) {
487 if (pos < ARR_LEN(ent->attr.mtd_attr.param_weight))
488 return ent->attr.mtd_attr.param_weight[pos];
493 analyze_method_params_weight(ent);
495 if (pos < ARR_LEN(ent->attr.mtd_attr.param_weight))
496 return ent->attr.mtd_attr.param_weight[pos];
502 * Analyze argument's weight of a given
505 * @param irg The ir graph to analyze.
507 void analyze_irg_args_weight(ir_graph *irg) {
510 ent = get_irg_entity(irg);
514 if (! ent->attr.mtd_attr.param_weight)
515 analyze_method_params_weight(ent);