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
41 #include "analyze_irg_args.h"
44 static void *VISITED = &v;
47 * Walk recursive the successors of a graph argument
48 * with mode reference and mark if it will be read,
51 * @param arg The graph argument with mode reference,
52 * that must be checked.
54 static unsigned analyze_arg(ir_node *arg, unsigned bits) {
58 /* We must visit a node once to avoid endless recursion.*/
59 set_irn_link(arg, VISITED);
61 for (i = get_irn_n_outs(arg) - 1; i >= 0; --i) {
62 succ = get_irn_out(arg, i);
65 if (get_irn_link(succ) == VISITED)
68 /* We should not walk over the memory edge.*/
69 if (get_irn_mode(succ) == mode_M)
72 /* If we reach with the recursion a Call node and our reference
73 isn't the address of this Call we accept that the reference will
74 be read and written if the graph of the method represented by
75 "Call" isn't computed else we analyze that graph. If our
76 reference is the address of this
77 Call node that mean the reference will be read.*/
78 switch (get_irn_opcode(succ)) {
81 ir_node *ptr = get_Call_ptr(succ);
84 /* Hmm: not sure what this is, most likely a read */
85 bits |= ptr_access_read;
90 meth_ent = get_Global_entity(ptr);
92 for (p = get_Call_n_params(succ) - 1; p >= 0; --p) {
93 if (get_Call_param(succ, p) == arg) {
94 /* an arg can be used more than once ! */
95 bits |= get_method_param_access(meth_ent, p);
98 } else if (is_Sel(ptr) && get_irp_callee_info_state() == irg_callee_info_consistent) {
99 /* is be a polymorphic call but callee information is available */
100 int i, n_params = get_Call_n_params(succ);
102 /* simply look into ALL possible callees */
103 for (i = get_Call_n_callees(succ) - 1; i >= 0; --i) {
104 meth_ent = get_Call_callee(succ, i);
106 /* unknown_entity is used to signal that we don't know what is called */
107 if (meth_ent == unknown_entity) {
108 bits |= ptr_access_all;
112 for (p = n_params - 1; p >= 0; --p) {
113 if (get_Call_param(succ, p) == arg) {
114 /* an arg can be used more than once ! */
115 bits |= get_method_param_access(meth_ent, p);
119 } else /* can do anything */
120 bits |= ptr_access_all;
123 /* search stops here anyway */
127 /* We have reached a Store node => the reference is written or stored. */
128 if (get_Store_ptr(succ) == arg) {
130 bits |= ptr_access_write;
133 bits |= ptr_access_store;
136 /* search stops here anyway */
140 /* We have reached a Load node => the reference is read. */
141 bits |= ptr_access_read;
143 /* search stops here anyway */
147 /* our address is casted into something unknown. Break our search. */
148 bits = ptr_access_all;
155 /* If we know that, the argument will be read, write and stored, we
156 can break the recursion.*/
157 if (bits == ptr_access_all) {
158 bits = ptr_access_all;
163 * A calculation that do not lead to a reference mode ends our search.
164 * This is dangerous: It would allow to cast into integer and that cast back ...
165 * so, when we detect a Conv we go mad, see the Conv case above.
167 if (!mode_is_reference(get_irn_mode(succ)))
170 /* follow further the address calculation */
171 bits = analyze_arg(succ, bits);
173 set_irn_link(arg, NULL);
178 * Check if a argument of the ir graph with mode
179 * reference is read, write or both.
181 * @param irg The ir graph to analyze.
183 static void analyze_ent_args(ir_entity *ent) {
185 ir_node *irg_args, *arg;
190 ptr_access_kind *rw_info;
192 mtp = get_entity_type(ent);
193 nparams = get_method_n_params(mtp);
195 ent->attr.mtd_attr.param_access = NEW_ARR_F(ptr_access_kind, nparams);
197 /* If the method haven't parameters we have
203 irg = get_entity_irg(ent);
205 /* we have not yet analyzed the graph, set ALL access for pointer args */
206 for (i = nparams - 1; i >= 0; --i) {
207 ir_type *type = get_method_param_type(mtp, i);
208 ent->attr.mtd_attr.param_access[i] = is_Pointer_type(type) ? ptr_access_all : ptr_access_none;
212 /* no graph, no better info */
216 assure_irg_outs(irg);
218 irg_args = get_irg_args(irg);
220 /* A array to save the information for each argument with
222 NEW_ARR_A(ptr_access_kind, rw_info, nparams);
224 /* We initialize the element with none state. */
225 for (i = nparams - 1; i >= 0; --i)
226 rw_info[i] = ptr_access_none;
228 /* search for arguments with mode reference
230 for (i = get_irn_n_outs(irg_args) - 1; i >= 0; --i) {
231 arg = get_irn_out(irg_args, i);
232 arg_mode = get_irn_mode(arg);
233 proj_nr = get_Proj_proj(arg);
235 if (mode_is_reference(arg_mode))
236 rw_info[proj_nr] |= analyze_arg(arg, rw_info[proj_nr]);
239 /* copy the temporary info */
240 memcpy(ent->attr.mtd_attr.param_access, rw_info,
241 nparams * sizeof(ent->attr.mtd_attr.param_access[0]));
244 printf("\n%s:\n", get_entity_name(ent));
245 for (i = 0; i < nparams; ++i) {
246 if (is_Pointer_type(get_method_param_type(mtp, i)))
247 if (ent->attr.mtd_attr.param_access[i] != ptr_access_none) {
248 printf(" Pointer Arg %d access: ", i);
249 if (ent->attr.mtd_attr.param_access[i] & ptr_access_read)
251 if (ent->attr.mtd_attr.param_access[i] & ptr_access_write)
253 if (ent->attr.mtd_attr.param_access[i] & ptr_access_store)
262 * Analyze how pointer arguments of a given
263 * ir graph are accessed.
265 * @param irg The ir graph to analyze.
267 void analyze_irg_args(ir_graph *irg) {
270 if (irg == get_const_code_irg())
273 ent = get_irg_entity(irg);
277 if (! ent->attr.mtd_attr.param_access)
278 analyze_ent_args(ent);
282 * Compute for a method with pointer parameter(s)
283 * if they will be read or written.
285 ptr_access_kind get_method_param_access(ir_entity *ent, int pos)
288 ir_type *mtp = get_entity_type(ent);
289 int is_variadic = get_method_variadicity(mtp) == variadicity_variadic;
291 assert(0 <= pos && (is_variadic || pos < get_method_n_params(mtp)));
294 if (ent->attr.mtd_attr.param_access) {
295 if (pos < ARR_LEN(ent->attr.mtd_attr.param_access))
296 return ent->attr.mtd_attr.param_access[pos];
298 return ptr_access_all;
301 analyze_ent_args(ent);
303 if (pos < ARR_LEN(ent->attr.mtd_attr.param_access))
304 return ent->attr.mtd_attr.param_access[pos];
306 return ptr_access_all;
309 /* Weights for parameters */
311 null_weight = 0, /**< If can't be anything optimized. */
312 binop_weight = 1, /**< If the argument have mode_weight and take part in binop. */
313 const_binop_weight = 1, /**< If the argument have mode_weight and take part in binop with a constant.*/
314 cmp_weight = 4, /**< If the argument take part in cmp. */
315 const_cmp_weight = 10, /**< If the argument take part in cmp with a constant. */
316 indirect_call_weight = 125, /**< If the argument is the address of an indirect Call. */
320 * Compute the weight of a method parameter
322 * @param arg The parameter them weight muss be computed.
324 static unsigned calc_method_param_weight(ir_node *arg) {
327 unsigned weight = null_weight;
329 /* We mark the nodes to avoid endless recursion */
330 set_irn_link(arg, VISITED);
332 for (i = get_irn_n_outs(arg) - 1; i >= 0; i--) {
333 succ = get_irn_out(arg, i);
336 if (get_irn_link(succ) == VISITED)
339 /* We should not walk over the memory edge.*/
340 if (get_irn_mode(succ) == mode_M)
343 switch (get_irn_opcode(succ)) {
345 if (get_Call_ptr(succ) == arg) {
346 /* the arguments is used as an pointer input for a call,
347 we can probably change an indirect Call into a direct one. */
348 weight += indirect_call_weight;
352 /* We have reached a cmp and we must increase the
353 weight with the cmp_weight. */
354 if (get_Cmp_left(succ) == arg)
355 op = get_Cmp_right(succ);
357 op = get_Cmp_left(succ);
359 if (is_irn_constlike(op)) {
360 weight += const_cmp_weight;
362 weight += cmp_weight;
365 /* the argument is used for a SwitchCond, a big win */
366 weight += const_cmp_weight * get_irn_n_outs(succ);
369 /* when looking backward we might find Id nodes */
370 weight += calc_method_param_weight(succ);
373 /* unoptimized tuple */
374 for (j = get_Tuple_n_preds(succ) - 1; j >= 0; --j) {
375 ir_node *pred = get_Tuple_pred(succ, j);
377 /* look for Proj(j) */
378 for (k = get_irn_n_outs(succ) - 1; k >= 0; --k) {
379 ir_node *succ_succ = get_irn_out(succ, k);
380 if (is_Proj(succ_succ)) {
381 if (get_Proj_proj(succ_succ) == j) {
383 weight += calc_method_param_weight(succ_succ);
386 /* this should NOT happen */
393 if (is_binop(succ)) {
394 /* We have reached a BinOp and we must increase the
395 weight with the binop_weight. If the other operand of the
396 BinOp is a constant we increase the weight with const_binop_weight
397 and call the function recursive.
399 if (get_binop_left(succ) == arg)
400 op = get_binop_right(succ);
402 op = get_binop_left(succ);
404 if (is_irn_constlike(op)) {
405 weight += const_binop_weight;
406 weight += calc_method_param_weight(succ);
408 weight += binop_weight;
409 } else if (is_unop(succ)) {
410 /* We have reached a binop and we must increase the
411 weight with the const_binop_weight and call the function recursive.*/
412 weight += const_binop_weight;
413 weight += calc_method_param_weight(succ);
418 set_irn_link(arg, NULL);
423 * Calculate a weight for each argument of an entity.
425 * @param ent The entity of the ir_graph.
427 static void analyze_method_params_weight(ir_entity *ent) {
430 int nparams, i, proj_nr;
431 ir_node *irg_args, *arg;
433 mtp = get_entity_type(ent);
434 nparams = get_method_n_params(mtp);
436 /* allocate a new array. currently used as 'analysed' flag */
437 ent->attr.mtd_attr.param_weight = NEW_ARR_F(unsigned, nparams);
439 /* If the method haven't parameters we have nothing to do. */
443 /* First we initialize the parameter weights with 0. */
444 for (i = nparams - 1; i >= 0; i--)
445 ent->attr.mtd_attr.param_weight[i] = null_weight;
447 irg = get_entity_irg(ent);
449 /* no graph, no better info */
453 /* Call algorithm that computes the out edges */
454 assure_irg_outs(irg);
456 irg_args = get_irg_args(irg);
457 for (i = get_irn_n_outs(irg_args) - 1; i >= 0; --i) {
458 arg = get_irn_out(irg_args, i);
459 proj_nr = get_Proj_proj(arg);
460 ent->attr.mtd_attr.param_weight[proj_nr] += calc_method_param_weight(arg);
464 printf("\n%s:\n", get_entity_name(ent));
465 for (i = nparams - 1; i >= 0; --i)
466 printf("The weight of argument %i is %f \n", i, ent->param_weight[i]);
471 * Returns for a method the 'weight' that every parameter
472 * has on optimization possibility. Higher values allows
473 * higher optimization with procedure cloning.
475 * The values are calculation on demand only.
477 * @param ent the entity to analyze
478 * @param pos the argument number
480 * @return the parameter weight or null_weight if pos is greater
481 * than the number of arguments.
483 unsigned get_method_param_weight(ir_entity *ent, int pos)
485 if (ent->attr.mtd_attr.param_weight) {
486 if (pos < ARR_LEN(ent->attr.mtd_attr.param_weight))
487 return ent->attr.mtd_attr.param_weight[pos];
492 analyze_method_params_weight(ent);
494 if (pos < ARR_LEN(ent->attr.mtd_attr.param_weight))
495 return ent->attr.mtd_attr.param_weight[pos];
501 * Analyze argument's weight of a given
504 * @param irg The ir graph to analyze.
506 void analyze_irg_args_weight(ir_graph *irg) {
509 ent = get_irg_entity(irg);
513 if (! ent->attr.mtd_attr.param_weight)
514 analyze_method_params_weight(ent);