- add a currently non-functioning mtp_property_returns_twice property
[libfirm] / ir / opt / opt_inline.c
1 /*
2  * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
3  *
4  * This file is part of libFirm.
5  *
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.
10  *
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.
14  *
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
17  * PURPOSE.
18  */
19
20 /**
21  * @file
22  * @brief    Dead node elimination and Procedure Inlining.
23  * @author   Michael Beck, Goetz Lindenmaier
24  * @version  $Id$
25  */
26 #include "config.h"
27
28 #include <limits.h>
29 #include <assert.h>
30
31 #include "irnode_t.h"
32 #include "irgraph_t.h"
33 #include "irprog_t.h"
34
35 #include "iroptimize.h"
36 #include "ircons_t.h"
37 #include "iropt_t.h"
38 #include "irgopt.h"
39 #include "irgmod.h"
40 #include "irgwalk.h"
41
42 #include "array_t.h"
43 #include "list.h"
44 #include "pset.h"
45 #include "pmap.h"
46 #include "pdeq.h"
47 #include "xmalloc.h"
48 #include "pqueue.h"
49
50 #include "irouts.h"
51 #include "irloop_t.h"
52 #include "irbackedge_t.h"
53 #include "opt_inline_t.h"
54 #include "cgana.h"
55 #include "trouts.h"
56 #include "error.h"
57
58 #include "analyze_irg_args.h"
59 #include "iredges_t.h"
60 #include "irflag_t.h"
61 #include "irhooks.h"
62 #include "irtools.h"
63 #include "iropt_dbg.h"
64
65 DEBUG_ONLY(static firm_dbg_module_t *dbg;)
66
67 /*------------------------------------------------------------------*/
68 /* Routines for dead node elimination / copying garbage collection  */
69 /* of the obstack.                                                  */
70 /*------------------------------------------------------------------*/
71
72 /**
73  * Remember the new node in the old node by using a field all nodes have.
74  */
75 #define set_new_node(oldn, newn)  set_irn_link(oldn, newn)
76
77 /**
78  * Get this new node, before the old node is forgotten.
79  */
80 #define get_new_node(oldn) get_irn_link(oldn)
81
82 /**
83  * Check if a new node was set.
84  */
85 #define has_new_node(n) (get_new_node(n) != NULL)
86
87 /**
88  * We use the block_visited flag to mark that we have computed the
89  * number of useful predecessors for this block.
90  * Further we encode the new arity in this flag in the old blocks.
91  * Remembering the arity is useful, as it saves a lot of pointer
92  * accesses.  This function is called for all Phi and Block nodes
93  * in a Block.
94  */
95 static inline int
96 compute_new_arity(ir_node *b) {
97         int i, res, irn_arity;
98         int irg_v, block_v;
99
100         irg_v = get_irg_block_visited(current_ir_graph);
101         block_v = get_Block_block_visited(b);
102         if (block_v >= irg_v) {
103                 /* we computed the number of preds for this block and saved it in the
104                    block_v flag */
105                 return block_v - irg_v;
106         } else {
107                 /* compute the number of good predecessors */
108                 res = irn_arity = get_irn_arity(b);
109                 for (i = 0; i < irn_arity; i++)
110                         if (is_Bad(get_irn_n(b, i))) res--;
111                         /* save it in the flag. */
112                         set_Block_block_visited(b, irg_v + res);
113                         return res;
114         }
115 }
116
117 /**
118  * Copies the node to the new obstack. The Ins of the new node point to
119  * the predecessors on the old obstack.  For block/phi nodes not all
120  * predecessors might be copied.  n->link points to the new node.
121  * For Phi and Block nodes the function allocates in-arrays with an arity
122  * only for useful predecessors.  The arity is determined by counting
123  * the non-bad predecessors of the block.
124  *
125  * @param n    The node to be copied
126  * @param env  if non-NULL, the node number attribute will be copied to the new node
127  *
128  * Note: Also used for loop unrolling.
129  */
130 static void copy_node(ir_node *n, void *env) {
131         ir_node *nn, *block;
132         int new_arity;
133         ir_op *op = get_irn_op(n);
134         (void) env;
135
136         if (op == op_Bad) {
137                 /* node copied already */
138                 return;
139         } else if (op == op_Block) {
140                 block = NULL;
141                 new_arity = compute_new_arity(n);
142                 n->attr.block.graph_arr = NULL;
143         } else {
144                 block = get_nodes_block(n);
145                 if (op == op_Phi) {
146                         new_arity = compute_new_arity(block);
147                 } else {
148                         new_arity = get_irn_arity(n);
149                 }
150         }
151         nn = new_ir_node(get_irn_dbg_info(n),
152                 current_ir_graph,
153                 block,
154                 op,
155                 get_irn_mode(n),
156                 new_arity,
157                 get_irn_in(n) + 1);
158         /* Copy the attributes.  These might point to additional data.  If this
159            was allocated on the old obstack the pointers now are dangling.  This
160            frees e.g. the memory of the graph_arr allocated in new_immBlock. */
161         if (op == op_Block) {
162                 /* we cannot allow blocks WITHOUT macroblock input */
163                 set_Block_MacroBlock(nn, get_Block_MacroBlock(n));
164         }
165         copy_node_attr(n, nn);
166
167 #ifdef DEBUG_libfirm
168         {
169                 int copy_node_nr = env != NULL;
170                 if (copy_node_nr) {
171                         /* for easier debugging, we want to copy the node numbers too */
172                         nn->node_nr = n->node_nr;
173                 }
174         }
175 #endif
176
177         set_new_node(n, nn);
178         hook_dead_node_elim_subst(current_ir_graph, n, nn);
179 }
180
181 /**
182  * Copies new predecessors of old node to new node remembered in link.
183  * Spare the Bad predecessors of Phi and Block nodes.
184  */
185 static void copy_preds(ir_node *n, void *env) {
186         ir_node *nn, *block;
187         int i, j, irn_arity;
188         (void) env;
189
190         nn = get_new_node(n);
191
192         if (is_Block(n)) {
193                 /* copy the macro block header */
194                 ir_node *mbh = get_Block_MacroBlock(n);
195
196                 if (mbh == n) {
197                         /* this block is a macroblock header */
198                         set_Block_MacroBlock(nn, nn);
199                 } else {
200                         /* get the macro block header */
201                         ir_node *nmbh = get_new_node(mbh);
202                         assert(nmbh != NULL);
203                         set_Block_MacroBlock(nn, nmbh);
204                 }
205
206                 /* Don't copy Bad nodes. */
207                 j = 0;
208                 irn_arity = get_irn_arity(n);
209                 for (i = 0; i < irn_arity; i++) {
210                         if (! is_Bad(get_irn_n(n, i))) {
211                                 ir_node *pred = get_irn_n(n, i);
212                                 set_irn_n(nn, j, get_new_node(pred));
213                                 j++;
214                         }
215                 }
216                 /* repair the block visited flag from above misuse. Repair it in both
217                    graphs so that the old one can still be used. */
218                 set_Block_block_visited(nn, 0);
219                 set_Block_block_visited(n, 0);
220                 /* Local optimization could not merge two subsequent blocks if
221                    in array contained Bads.  Now it's possible.
222                    We don't call optimize_in_place as it requires
223                    that the fields in ir_graph are set properly. */
224                 if (!has_Block_label(nn) &&
225                     get_opt_control_flow_straightening() &&
226                     get_Block_n_cfgpreds(nn) == 1 &&
227                     is_Jmp(get_Block_cfgpred(nn, 0))) {
228                         ir_node *old = get_nodes_block(get_Block_cfgpred(nn, 0));
229                         if (nn == old) {
230                                 /* Jmp jumps into the block it is in -- deal self cycle. */
231                                 assert(is_Bad(get_new_node(get_irg_bad(current_ir_graph))));
232                                 exchange(nn, get_new_node(get_irg_bad(current_ir_graph)));
233                         } else {
234                                 exchange(nn, old);
235                         }
236                 }
237         } else if (is_Phi(n) && get_irn_arity(n) > 0) {
238                 /* Don't copy node if corresponding predecessor in block is Bad.
239                    The Block itself should not be Bad. */
240                 block = get_nodes_block(n);
241                 set_nodes_block(nn, get_new_node(block));
242                 j = 0;
243                 irn_arity = get_irn_arity(n);
244                 for (i = 0; i < irn_arity; i++) {
245                         if (! is_Bad(get_irn_n(block, i))) {
246                                 ir_node *pred = get_irn_n(n, i);
247                                 set_irn_n(nn, j, get_new_node(pred));
248                                 /*if (is_backedge(n, i)) set_backedge(nn, j);*/
249                                 j++;
250                         }
251                 }
252                 /* If the pre walker reached this Phi after the post walker visited the
253                    block block_visited is > 0. */
254                 set_Block_block_visited(get_nodes_block(n), 0);
255                 /* Compacting the Phi's ins might generate Phis with only one
256                    predecessor. */
257                 if (get_irn_arity(nn) == 1)
258                         exchange(nn, get_irn_n(nn, 0));
259         } else {
260                 irn_arity = get_irn_arity(n);
261                 for (i = -1; i < irn_arity; i++)
262                         set_irn_n(nn, i, get_new_node(get_irn_n(n, i)));
263         }
264         /* Now the new node is complete.  We can add it to the hash table for CSE.
265            @@@ inlining aborts if we identify End. Why? */
266         if (!is_End(nn))
267                 add_identities(current_ir_graph->value_table, nn);
268 }
269
270 /**
271  * Copies the graph recursively, compacts the keep-alives of the end node.
272  *
273  * @param irg           the graph to be copied
274  * @param copy_node_nr  If non-zero, the node number will be copied
275  */
276 static void copy_graph(ir_graph *irg, int copy_node_nr) {
277         ir_node *oe, *ne, *ob, *nb, *om, *nm; /* old end, new end, old bad, new bad, old NoMem, new NoMem */
278         ir_node *ka;      /* keep alive */
279         int i, irn_arity;
280         unsigned long vfl;
281
282         /* Some nodes must be copied by hand, sigh */
283         vfl = get_irg_visited(irg);
284         set_irg_visited(irg, vfl + 1);
285
286         oe = get_irg_end(irg);
287         mark_irn_visited(oe);
288         /* copy the end node by hand, allocate dynamic in array! */
289         ne = new_ir_node(get_irn_dbg_info(oe),
290                 irg,
291                 NULL,
292                 op_End,
293                 mode_X,
294                 -1,
295                 NULL);
296         /* Copy the attributes.  Well, there might be some in the future... */
297         copy_node_attr(oe, ne);
298         set_new_node(oe, ne);
299
300         /* copy the Bad node */
301         ob = get_irg_bad(irg);
302         mark_irn_visited(ob);
303         nb = new_ir_node(get_irn_dbg_info(ob),
304                 irg,
305                 NULL,
306                 op_Bad,
307                 mode_T,
308                 0,
309                 NULL);
310         copy_node_attr(ob, nb);
311         set_new_node(ob, nb);
312
313         /* copy the NoMem node */
314         om = get_irg_no_mem(irg);
315         mark_irn_visited(om);
316         nm = new_ir_node(get_irn_dbg_info(om),
317                 irg,
318                 NULL,
319                 op_NoMem,
320                 mode_M,
321                 0,
322                 NULL);
323         copy_node_attr(om, nm);
324         set_new_node(om, nm);
325
326         /* copy the live nodes */
327         set_irg_visited(irg, vfl);
328         irg_walk(get_nodes_block(oe), copy_node, copy_preds, INT_TO_PTR(copy_node_nr));
329
330         /* Note: from yet, the visited flag of the graph is equal to vfl + 1 */
331
332         /* visit the anchors as well */
333         for (i = get_irg_n_anchors(irg) - 1; i >= 0; --i) {
334                 ir_node *n = get_irg_anchor(irg, i);
335
336                 if (n && (get_irn_visited(n) <= vfl)) {
337                         set_irg_visited(irg, vfl);
338                         irg_walk(n, copy_node, copy_preds, INT_TO_PTR(copy_node_nr));
339                 }
340         }
341
342         /* copy_preds for the end node ... */
343         set_nodes_block(ne, get_new_node(get_nodes_block(oe)));
344
345         /*- ... and now the keep alives. -*/
346         /* First pick the not marked block nodes and walk them.  We must pick these
347            first as else we will oversee blocks reachable from Phis. */
348         irn_arity = get_End_n_keepalives(oe);
349         for (i = 0; i < irn_arity; i++) {
350                 ka = get_End_keepalive(oe, i);
351                 if (is_Block(ka)) {
352                         if (get_irn_visited(ka) <= vfl) {
353                                 /* We must keep the block alive and copy everything reachable */
354                                 set_irg_visited(irg, vfl);
355                                 irg_walk(ka, copy_node, copy_preds, INT_TO_PTR(copy_node_nr));
356                         }
357                         add_End_keepalive(ne, get_new_node(ka));
358                 }
359         }
360
361         /* Now pick other nodes.  Here we will keep all! */
362         irn_arity = get_End_n_keepalives(oe);
363         for (i = 0; i < irn_arity; i++) {
364                 ka = get_End_keepalive(oe, i);
365                 if (!is_Block(ka)) {
366                         if (get_irn_visited(ka) <= vfl) {
367                                 /* We didn't copy the node yet.  */
368                                 set_irg_visited(irg, vfl);
369                                 irg_walk(ka, copy_node, copy_preds, INT_TO_PTR(copy_node_nr));
370                         }
371                         add_End_keepalive(ne, get_new_node(ka));
372                 }
373         }
374
375         /* start block sometimes only reached after keep alives */
376         set_nodes_block(nb, get_new_node(get_nodes_block(ob)));
377         set_nodes_block(nm, get_new_node(get_nodes_block(om)));
378 }
379
380 /**
381  * Copies the graph reachable from current_ir_graph->end to the obstack
382  * in current_ir_graph and fixes the environment.
383  * Then fixes the fields in current_ir_graph containing nodes of the
384  * graph.
385  *
386  * @param copy_node_nr  If non-zero, the node number will be copied
387  */
388 static void
389 copy_graph_env(int copy_node_nr) {
390         ir_graph *irg = current_ir_graph;
391         ir_node *old_end, *new_anchor;
392         int i;
393
394         /* remove end_except and end_reg nodes */
395         old_end = get_irg_end(irg);
396         set_irg_end_except (irg, old_end);
397         set_irg_end_reg    (irg, old_end);
398
399         /* Not all nodes remembered in irg might be reachable
400            from the end node.  Assure their link is set to NULL, so that
401            we can test whether new nodes have been computed. */
402         for (i = get_irg_n_anchors(irg) - 1; i >= 0; --i) {
403                 ir_node *n = get_irg_anchor(irg, i);
404                 if (n != NULL)
405                         set_new_node(n, NULL);
406         }
407         /* we use the block walk flag for removing Bads from Blocks ins. */
408         inc_irg_block_visited(irg);
409
410         /* copy the graph */
411         copy_graph(irg, copy_node_nr);
412
413         /* fix the anchor */
414         old_end    = get_irg_end(irg);
415         new_anchor = new_Anchor(irg);
416
417         for (i = get_irg_n_anchors(irg) - 1; i >= 0; --i) {
418                 ir_node *n = get_irg_anchor(irg, i);
419                 if (n)
420                         set_irn_n(new_anchor, i, get_new_node(n));
421         }
422         free_End(old_end);
423         irg->anchor = new_anchor;
424
425         /* ensure the new anchor is placed in the endblock */
426         set_nodes_block(new_anchor, get_irg_end_block(irg));
427 }
428
429 /**
430  * Copies all reachable nodes to a new obstack.  Removes bad inputs
431  * from block nodes and the corresponding inputs from Phi nodes.
432  * Merges single exit blocks with single entry blocks and removes
433  * 1-input Phis.
434  * Adds all new nodes to a new hash table for CSE.  Does not
435  * perform CSE, so the hash table might contain common subexpressions.
436  */
437 void dead_node_elimination(ir_graph *irg) {
438         ir_graph *rem;
439 #ifdef INTERPROCEDURAL_VIEW
440         int rem_ipview = get_interprocedural_view();
441 #endif
442         struct obstack *graveyard_obst = NULL;
443         struct obstack *rebirth_obst   = NULL;
444
445         edges_deactivate(irg);
446
447         /* inform statistics that we started a dead-node elimination run */
448         hook_dead_node_elim(irg, 1);
449
450         /* Remember external state of current_ir_graph. */
451         rem = current_ir_graph;
452         current_ir_graph = irg;
453 #ifdef INTERPROCEDURAL_VIEW
454         set_interprocedural_view(0);
455 #endif
456
457         assert(get_irg_phase_state(irg) != phase_building);
458
459         /* Handle graph state */
460         free_callee_info(irg);
461         free_irg_outs(irg);
462         free_trouts();
463
464         /* @@@ so far we loose loops when copying */
465         free_loop_information(irg);
466
467         set_irg_doms_inconsistent(irg);
468
469         /* A quiet place, where the old obstack can rest in peace,
470            until it will be cremated. */
471         graveyard_obst = irg->obst;
472
473         /* A new obstack, where the reachable nodes will be copied to. */
474         rebirth_obst = XMALLOC(struct obstack);
475         irg->obst = rebirth_obst;
476         obstack_init(irg->obst);
477         irg->last_node_idx = 0;
478
479         /* We also need a new value table for CSE */
480         del_identities(irg->value_table);
481         irg->value_table = new_identities();
482
483         /* Copy the graph from the old to the new obstack */
484         copy_graph_env(/*copy_node_nr=*/1);
485
486         /* Free memory from old unoptimized obstack */
487         obstack_free(graveyard_obst, 0);  /* First empty the obstack ... */
488         xfree(graveyard_obst);            /* ... then free it.           */
489
490         /* inform statistics that the run is over */
491         hook_dead_node_elim(irg, 0);
492
493         current_ir_graph = rem;
494 #ifdef INTERPROCEDURAL_VIEW
495         set_interprocedural_view(rem_ipview);
496 #endif
497 }
498
499 /**
500  * Relink bad predecessors of a block and store the old in array to the
501  * link field. This function is called by relink_bad_predecessors().
502  * The array of link field starts with the block operand at position 0.
503  * If block has bad predecessors, create a new in array without bad preds.
504  * Otherwise let in array untouched.
505  */
506 static void relink_bad_block_predecessors(ir_node *n, void *env) {
507         ir_node **new_in, *irn;
508         int i, new_irn_n, old_irn_arity, new_irn_arity = 0;
509         (void) env;
510
511         /* if link field of block is NULL, look for bad predecessors otherwise
512            this is already done */
513         if (is_Block(n) && get_irn_link(n) == NULL) {
514                 /* save old predecessors in link field (position 0 is the block operand)*/
515                 set_irn_link(n, get_irn_in(n));
516
517                 /* count predecessors without bad nodes */
518                 old_irn_arity = get_irn_arity(n);
519                 for (i = 0; i < old_irn_arity; i++)
520                         if (!is_Bad(get_irn_n(n, i)))
521                                 ++new_irn_arity;
522
523                 /* arity changing: set new predecessors without bad nodes */
524                 if (new_irn_arity < old_irn_arity) {
525                         /* Get new predecessor array. We do not resize the array, as we must
526                            keep the old one to update Phis. */
527                         new_in = NEW_ARR_D(ir_node *, current_ir_graph->obst, (new_irn_arity+1));
528
529                         /* set new predecessors in array */
530                         new_in[0] = NULL;
531                         new_irn_n = 1;
532                         for (i = 0; i < old_irn_arity; i++) {
533                                 irn = get_irn_n(n, i);
534                                 if (!is_Bad(irn)) {
535                                         new_in[new_irn_n] = irn;
536                                         is_backedge(n, i) ? set_backedge(n, new_irn_n-1) : set_not_backedge(n, new_irn_n-1);
537                                         ++new_irn_n;
538                                 }
539                         }
540                         /* ARR_SETLEN(int, n->attr.block.backedge, new_irn_arity); */
541                         ARR_SHRINKLEN(n->attr.block.backedge, new_irn_arity);
542                         n->in = new_in;
543                 } /* ir node has bad predecessors */
544         } /* Block is not relinked */
545 }
546
547 /**
548  * Relinks Bad predecessors from Blocks and Phis called by walker
549  * remove_bad_predecesors(). If n is a Block, call
550  * relink_bad_block_redecessors(). If n is a Phi-node, call also the relinking
551  * function of Phi's Block. If this block has bad predecessors, relink preds
552  * of the Phi-node.
553  */
554 static void relink_bad_predecessors(ir_node *n, void *env) {
555         ir_node *block, **old_in;
556         int i, old_irn_arity, new_irn_arity;
557
558         /* relink bad predecessors of a block */
559         if (is_Block(n))
560                 relink_bad_block_predecessors(n, env);
561
562         /* If Phi node relink its block and its predecessors */
563         if (is_Phi(n)) {
564                 /* Relink predecessors of phi's block */
565                 block = get_nodes_block(n);
566                 if (get_irn_link(block) == NULL)
567                         relink_bad_block_predecessors(block, env);
568
569                 old_in = (ir_node **)get_irn_link(block); /* Of Phi's Block */
570                 old_irn_arity = ARR_LEN(old_in);
571
572                 /* Relink Phi predecessors if count of predecessors changed */
573                 if (old_irn_arity != ARR_LEN(get_irn_in(block))) {
574                         /* set new predecessors in array
575                            n->in[0] remains the same block */
576                         new_irn_arity = 1;
577                         for(i = 1; i < old_irn_arity; i++)
578                                 if (!is_Bad(old_in[i])) {
579                                         n->in[new_irn_arity] = n->in[i];
580                                         is_backedge(n, i) ? set_backedge(n, new_irn_arity) : set_not_backedge(n, new_irn_arity);
581                                         ++new_irn_arity;
582                                 }
583
584                                 ARR_SETLEN(ir_node *, n->in, new_irn_arity);
585                                 ARR_SETLEN(int, n->attr.phi.u.backedge, new_irn_arity);
586                 }
587         } /* n is a Phi node */
588 }
589
590 /*
591  * Removes Bad Bad predecessors from Blocks and the corresponding
592  * inputs to Phi nodes as in dead_node_elimination but without
593  * copying the graph.
594  * On walking up set the link field to NULL, on walking down call
595  * relink_bad_predecessors() (This function stores the old in array
596  * to the link field and sets a new in array if arity of predecessors
597  * changes).
598  */
599 void remove_bad_predecessors(ir_graph *irg) {
600         panic("Fix backedge handling first");
601         irg_walk_graph(irg, firm_clear_link, relink_bad_predecessors, NULL);
602 }
603
604
605 /*
606    __                      _  __ __
607   (_     __    o     _    | \/  |_
608   __)|_| | \_/ | \_/(/_   |_/\__|__
609
610   The following stuff implements a facility that automatically patches
611   registered ir_node pointers to the new node when a dead node elimination occurs.
612 */
613
614 struct _survive_dce_t {
615         struct obstack obst;
616         pmap *places;
617         pmap *new_places;
618         hook_entry_t dead_node_elim;
619         hook_entry_t dead_node_elim_subst;
620 };
621
622 typedef struct _survive_dce_list_t {
623         struct _survive_dce_list_t *next;
624         ir_node **place;
625 } survive_dce_list_t;
626
627 static void dead_node_hook(void *context, ir_graph *irg, int start) {
628         survive_dce_t *sd = context;
629         (void) irg;
630
631         /* Create a new map before the dead node elimination is performed. */
632         if (start) {
633                 sd->new_places = pmap_create_ex(pmap_count(sd->places));
634         } else {
635                 /* Patch back all nodes if dead node elimination is over and something is to be done. */
636                 pmap_destroy(sd->places);
637                 sd->places     = sd->new_places;
638                 sd->new_places = NULL;
639         }
640 }
641
642 /**
643  * Hook called when dead node elimination replaces old by nw.
644  */
645 static void dead_node_subst_hook(void *context, ir_graph *irg, ir_node *old, ir_node *nw) {
646         survive_dce_t *sd = context;
647         survive_dce_list_t *list = pmap_get(sd->places, old);
648         (void) irg;
649
650         /* If the node is to be patched back, write the new address to all registered locations. */
651         if (list) {
652                 survive_dce_list_t *p;
653
654                 for (p = list; p; p = p->next)
655                         *(p->place) = nw;
656
657                 pmap_insert(sd->new_places, nw, list);
658         }
659 }
660
661 /**
662  * Make a new Survive DCE environment.
663  */
664 survive_dce_t *new_survive_dce(void) {
665         survive_dce_t *res = XMALLOC(survive_dce_t);
666         obstack_init(&res->obst);
667         res->places     = pmap_create();
668         res->new_places = NULL;
669
670         res->dead_node_elim.hook._hook_dead_node_elim = dead_node_hook;
671         res->dead_node_elim.context                   = res;
672         res->dead_node_elim.next                      = NULL;
673
674         res->dead_node_elim_subst.hook._hook_dead_node_elim_subst = dead_node_subst_hook;
675         res->dead_node_elim_subst.context = res;
676         res->dead_node_elim_subst.next    = NULL;
677
678         register_hook(hook_dead_node_elim, &res->dead_node_elim);
679         register_hook(hook_dead_node_elim_subst, &res->dead_node_elim_subst);
680         return res;
681 }
682
683 /**
684  * Free a Survive DCE environment.
685  */
686 void free_survive_dce(survive_dce_t *sd) {
687         obstack_free(&sd->obst, NULL);
688         pmap_destroy(sd->places);
689         unregister_hook(hook_dead_node_elim, &sd->dead_node_elim);
690         unregister_hook(hook_dead_node_elim_subst, &sd->dead_node_elim_subst);
691         xfree(sd);
692 }
693
694 /**
695  * Register a node pointer to be patched upon DCE.
696  * When DCE occurs, the node pointer specified by @p place will be
697  * patched to the new address of the node it is pointing to.
698  *
699  * @param sd    The Survive DCE environment.
700  * @param place The address of the node pointer.
701  */
702 void survive_dce_register_irn(survive_dce_t *sd, ir_node **place) {
703         if (*place != NULL) {
704                 ir_node *irn      = *place;
705                 survive_dce_list_t *curr = pmap_get(sd->places, irn);
706                 survive_dce_list_t *nw   = obstack_alloc(&sd->obst, sizeof(nw[0]));
707
708                 nw->next  = curr;
709                 nw->place = place;
710
711                 pmap_insert(sd->places, irn, nw);
712         }
713 }
714
715 /*--------------------------------------------------------------------*/
716 /*  Functionality for inlining                                         */
717 /*--------------------------------------------------------------------*/
718
719 /**
720  * Copy node for inlineing.  Updates attributes that change when
721  * inlineing but not for dead node elimination.
722  *
723  * Copies the node by calling copy_node() and then updates the entity if
724  * it's a local one.  env must be a pointer of the frame type of the
725  * inlined procedure. The new entities must be in the link field of
726  * the entities.
727  */
728 static void copy_node_inline(ir_node *n, void *env) {
729         ir_node *nn;
730         ir_type *frame_tp = (ir_type *)env;
731
732         copy_node(n, NULL);
733         if (is_Sel(n)) {
734                 nn = get_new_node (n);
735                 assert(is_Sel(nn));
736                 if (get_entity_owner(get_Sel_entity(n)) == frame_tp) {
737                         set_Sel_entity(nn, get_entity_link(get_Sel_entity(n)));
738                 }
739         } else if (is_Block(n)) {
740                 nn = get_new_node (n);
741                 nn->attr.block.irg = current_ir_graph;
742         }
743 }
744
745 /**
746  * Copies new predecessors of old node and move constants to
747  * the Start Block.
748  */
749 static void copy_preds_inline(ir_node *n, void *env) {
750         ir_node *nn;
751
752         copy_preds(n, env);
753         nn = skip_Id(get_new_node(n));
754         if (is_irn_constlike(nn)) {
755                 /* move Constants into the start block */
756                 set_nodes_block(nn, get_irg_start_block(current_ir_graph));
757
758                 n = identify_remember(current_ir_graph->value_table, nn);
759                 if (nn != n) {
760                         DBG_OPT_CSE(nn, n);
761                         exchange(nn, n);
762                 }
763         }
764 }
765
766 /**
767  * Walker: checks if P_value_arg_base is used.
768  */
769 static void find_addr(ir_node *node, void *env) {
770         int *allow_inline = env;
771         if (is_Proj(node) &&
772                         is_Start(get_Proj_pred(node)) &&
773                         get_Proj_proj(node) == pn_Start_P_value_arg_base) {
774                 *allow_inline = 0;
775         } else if (is_Alloc(node) && get_Alloc_where(node) == stack_alloc) {
776                 /* From GCC:
777                  * Refuse to inline alloca call unless user explicitly forced so as this
778                  * may change program's memory overhead drastically when the function
779                  * using alloca is called in loop.  In GCC present in SPEC2000 inlining
780                  * into schedule_block cause it to require 2GB of ram instead of 256MB.
781                  *
782                  * Sorrily this is true with our implementation also.
783                  * Moreover, we cannot differentiate between alloca() and VLA yet, so this
784                  * disables inlining of functions using VLA (with are completely save).
785                  *
786                  * 2 Solutions:
787                  * - add a flag to the Alloc node for "real" alloca() calls
788                  * - add a new Stack-Restore node at the end of a function using alloca()
789                  */
790                 *allow_inline = 0;
791         }
792 }
793
794 /**
795  * Check if we can inline a given call.
796  * Currently, we cannot inline two cases:
797  * - call with compound arguments
798  * - graphs that take the address of a parameter
799  *
800  * check these conditions here
801  */
802 static int can_inline(ir_node *call, ir_graph *called_graph) {
803         ir_type *call_type = get_Call_type(call);
804         int params, ress, i, res;
805         assert(is_Method_type(call_type));
806
807         params = get_method_n_params(call_type);
808         ress   = get_method_n_ress(call_type);
809
810         /* check parameters for compound arguments */
811         for (i = 0; i < params; ++i) {
812                 ir_type *p_type = get_method_param_type(call_type, i);
813
814                 if (is_compound_type(p_type))
815                         return 0;
816         }
817
818         /* check results for compound arguments */
819         for (i = 0; i < ress; ++i) {
820                 ir_type *r_type = get_method_res_type(call_type, i);
821
822                 if (is_compound_type(r_type))
823                         return 0;
824         }
825
826         res = 1;
827         irg_walk_graph(called_graph, find_addr, NULL, &res);
828
829         return res;
830 }
831
832 enum exc_mode {
833         exc_handler    = 0, /**< There is a handler. */
834         exc_to_end     = 1, /**< Branches to End. */
835         exc_no_handler = 2  /**< Exception handling not represented. */
836 };
837
838 /* Inlines a method at the given call site. */
839 int inline_method(ir_node *call, ir_graph *called_graph) {
840         ir_node             *pre_call;
841         ir_node             *post_call, *post_bl;
842         ir_node             *in[pn_Start_max];
843         ir_node             *end, *end_bl, *block;
844         ir_node             **res_pred;
845         ir_node             **cf_pred;
846         ir_node             **args_in;
847         ir_node             *ret, *phi;
848         int                 arity, n_ret, n_exc, n_res, i, n, j, rem_opt, irn_arity, n_params;
849         enum exc_mode       exc_handling;
850         ir_type             *called_frame, *curr_frame, *mtp, *ctp;
851         ir_entity           *ent;
852         ir_graph            *rem, *irg;
853         irg_inline_property prop = get_irg_inline_property(called_graph);
854         unsigned long       visited;
855
856         if (prop == irg_inline_forbidden)
857                 return 0;
858
859         ent = get_irg_entity(called_graph);
860
861         mtp = get_entity_type(ent);
862         ctp = get_Call_type(call);
863         if (get_method_n_params(mtp) > get_method_n_params(ctp)) {
864                 /* this is a bad feature of C: without a prototype, we can can call a function with less
865                 parameters than needed. Currently we don't support this, although it would be
866                 to use Unknown than. */
867                 return 0;
868         }
869
870         /* Argh, compiling C has some bad consequences:
871            the call type AND the method type might be different.
872            It is implementation defendant what happens in that case.
873            We support inlining, if the bitsize of the types matches AND
874            the same arithmetic is used. */
875         n_params = get_method_n_params(mtp);
876         for (i = n_params - 1; i >= 0; --i) {
877                 ir_type *param_tp = get_method_param_type(mtp, i);
878                 ir_type *arg_tp   = get_method_param_type(ctp, i);
879
880                 if (param_tp != arg_tp) {
881                         ir_mode *pmode = get_type_mode(param_tp);
882                         ir_mode *amode = get_type_mode(arg_tp);
883
884                         if (pmode == NULL || amode == NULL)
885                                 return 0;
886                         if (get_mode_size_bits(pmode) != get_mode_size_bits(amode))
887                                 return 0;
888                         if (get_mode_arithmetic(pmode) != get_mode_arithmetic(amode))
889                                 return 0;
890                         /* otherwise we can simply "reinterpret" the bits */
891                 }
892         }
893
894         irg = get_irn_irg(call);
895
896         /*
897          * We cannot inline a recursive call. The graph must be copied before
898          * the call the inline_method() using create_irg_copy().
899          */
900         if (called_graph == irg)
901                 return 0;
902
903         /*
904          * currently, we cannot inline two cases:
905          * - call with compound arguments
906          * - graphs that take the address of a parameter
907          */
908         if (! can_inline(call, called_graph))
909                 return 0;
910
911         rem = current_ir_graph;
912         current_ir_graph = irg;
913
914         DB((dbg, LEVEL_1, "Inlining %+F(%+F) into %+F\n", call, called_graph, irg));
915
916         /* --  Turn off optimizations, this can cause problems when allocating new nodes. -- */
917         rem_opt = get_opt_optimize();
918         set_optimize(0);
919
920         /* Handle graph state */
921         assert(get_irg_phase_state(irg) != phase_building);
922         assert(get_irg_pinned(irg) == op_pin_state_pinned);
923         assert(get_irg_pinned(called_graph) == op_pin_state_pinned);
924         set_irg_outs_inconsistent(irg);
925         set_irg_extblk_inconsistent(irg);
926         set_irg_doms_inconsistent(irg);
927         set_irg_loopinfo_inconsistent(irg);
928         set_irg_callee_info_state(irg, irg_callee_info_inconsistent);
929
930         /* -- Check preconditions -- */
931         assert(is_Call(call));
932
933         /* here we know we WILL inline, so inform the statistics */
934         hook_inline(call, called_graph);
935
936         /* -- Decide how to handle exception control flow: Is there a handler
937            for the Call node, or do we branch directly to End on an exception?
938            exc_handling:
939            0 There is a handler.
940            1 Branches to End.
941            2 Exception handling not represented in Firm. -- */
942         {
943                 ir_node *proj, *Mproj = NULL, *Xproj = NULL;
944                 for (proj = get_irn_link(call); proj; proj = get_irn_link(proj)) {
945                         long proj_nr = get_Proj_proj(proj);
946                         if (proj_nr == pn_Call_X_except) Xproj = proj;
947                         if (proj_nr == pn_Call_M_except) Mproj = proj;
948                 }
949                 if      (Mproj) { assert(Xproj); exc_handling = exc_handler; } /*  Mproj           */
950                 else if (Xproj) {                exc_handling = exc_to_end; } /* !Mproj &&  Xproj   */
951                 else            {                exc_handling = exc_no_handler; } /* !Mproj && !Xproj   */
952         }
953
954         /* create the argument tuple */
955         NEW_ARR_A(ir_type *, args_in, n_params);
956
957         block = get_nodes_block(call);
958         for (i = n_params - 1; i >= 0; --i) {
959                 ir_node *arg      = get_Call_param(call, i);
960                 ir_type *param_tp = get_method_param_type(mtp, i);
961                 ir_mode *mode     = get_type_mode(param_tp);
962
963                 if (mode != get_irn_mode(arg)) {
964                         arg = new_r_Conv(irg, block, arg, mode);
965                 }
966                 args_in[i] = arg;
967         }
968
969         /* --
970            the procedure and later replaces the Start node of the called graph.
971            Post_call is the old Call node and collects the results of the called
972            graph. Both will end up being a tuple.  -- */
973         post_bl = get_nodes_block(call);
974         set_irg_current_block(irg, post_bl);
975         /* XxMxPxPxPxT of Start + parameter of Call */
976         in[pn_Start_X_initial_exec]   = new_Jmp();
977         in[pn_Start_M]                = get_Call_mem(call);
978         in[pn_Start_P_frame_base]     = get_irg_frame(irg);
979         in[pn_Start_P_tls]            = get_irg_tls(irg);
980         in[pn_Start_T_args]           = new_Tuple(n_params, args_in);
981         /* in[pn_Start_P_value_arg_base] = ??? */
982         assert(pn_Start_P_value_arg_base == pn_Start_max - 1 && "pn_Start_P_value_arg_base not supported, fix");
983         pre_call = new_Tuple(pn_Start_max - 1, in);
984         post_call = call;
985
986         /* --
987            The new block gets the ins of the old block, pre_call and all its
988            predecessors and all Phi nodes. -- */
989         part_block(pre_call);
990
991         /* -- Prepare state for dead node elimination -- */
992         /* Visited flags in calling irg must be >= flag in called irg.
993            Else walker and arity computation will not work. */
994         if (get_irg_visited(irg) <= get_irg_visited(called_graph))
995                 set_irg_visited(irg, get_irg_visited(called_graph) + 1);
996         if (get_irg_block_visited(irg) < get_irg_block_visited(called_graph))
997                 set_irg_block_visited(irg, get_irg_block_visited(called_graph));
998         visited = get_irg_visited(irg);
999
1000         /* Set pre_call as new Start node in link field of the start node of
1001            calling graph and pre_calls block as new block for the start block
1002            of calling graph.
1003            Further mark these nodes so that they are not visited by the
1004            copying. */
1005         set_irn_link(get_irg_start(called_graph), pre_call);
1006         set_irn_visited(get_irg_start(called_graph), visited);
1007         set_irn_link(get_irg_start_block(called_graph), get_nodes_block(pre_call));
1008         set_irn_visited(get_irg_start_block(called_graph), visited);
1009
1010         set_irn_link(get_irg_bad(called_graph), get_irg_bad(current_ir_graph));
1011         set_irn_visited(get_irg_bad(called_graph), visited);
1012
1013         set_irn_link(get_irg_no_mem(called_graph), get_irg_no_mem(current_ir_graph));
1014         set_irn_visited(get_irg_no_mem(called_graph), visited);
1015
1016         /* Initialize for compaction of in arrays */
1017         inc_irg_block_visited(irg);
1018
1019         /* -- Replicate local entities of the called_graph -- */
1020         /* copy the entities. */
1021         irp_reserve_resources(irp, IR_RESOURCE_ENTITY_LINK);
1022         called_frame = get_irg_frame_type(called_graph);
1023         curr_frame   = get_irg_frame_type(irg);
1024         for (i = 0, n = get_class_n_members(called_frame); i < n; ++i) {
1025                 ir_entity *new_ent, *old_ent;
1026                 old_ent = get_class_member(called_frame, i);
1027                 new_ent = copy_entity_own(old_ent, curr_frame);
1028                 set_entity_link(old_ent, new_ent);
1029         }
1030
1031         /* visited is > than that of called graph.  With this trick visited will
1032            remain unchanged so that an outer walker, e.g., searching the call nodes
1033             to inline, calling this inline will not visit the inlined nodes. */
1034         set_irg_visited(irg, get_irg_visited(irg)-1);
1035
1036         /* -- Performing dead node elimination inlines the graph -- */
1037         /* Copies the nodes to the obstack of current_ir_graph. Updates links to new
1038            entities. */
1039         irg_walk(get_irg_end(called_graph), copy_node_inline, copy_preds_inline,
1040                  get_irg_frame_type(called_graph));
1041
1042         irp_free_resources(irp, IR_RESOURCE_ENTITY_LINK);
1043
1044         /* Repair called_graph */
1045         set_irg_visited(called_graph, get_irg_visited(irg));
1046         set_irg_block_visited(called_graph, get_irg_block_visited(irg));
1047         set_Block_block_visited(get_irg_start_block(called_graph), 0);
1048
1049         /* -- Merge the end of the inlined procedure with the call site -- */
1050         /* We will turn the old Call node into a Tuple with the following
1051            predecessors:
1052            -1:  Block of Tuple.
1053            0: Phi of all Memories of Return statements.
1054            1: Jmp from new Block that merges the control flow from all exception
1055            predecessors of the old end block.
1056            2: Tuple of all arguments.
1057            3: Phi of Exception memories.
1058            In case the old Call directly branches to End on an exception we don't
1059            need the block merging all exceptions nor the Phi of the exception
1060            memories.
1061         */
1062
1063         /* -- Precompute some values -- */
1064         end_bl = get_new_node(get_irg_end_block(called_graph));
1065         end = get_new_node(get_irg_end(called_graph));
1066         arity = get_Block_n_cfgpreds(end_bl);    /* arity = n_exc + n_ret  */
1067         n_res = get_method_n_ress(get_Call_type(call));
1068
1069         res_pred = XMALLOCN(ir_node*, n_res);
1070         cf_pred  = XMALLOCN(ir_node*, arity);
1071
1072         set_irg_current_block(irg, post_bl); /* just to make sure */
1073
1074         /* -- archive keepalives -- */
1075         irn_arity = get_irn_arity(end);
1076         for (i = 0; i < irn_arity; i++) {
1077                 ir_node *ka = get_End_keepalive(end, i);
1078                 if (! is_Bad(ka))
1079                         add_End_keepalive(get_irg_end(irg), ka);
1080         }
1081
1082         /* The new end node will die.  We need not free as the in array is on the obstack:
1083            copy_node() only generated 'D' arrays. */
1084
1085         /* -- Replace Return nodes by Jump nodes. -- */
1086         n_ret = 0;
1087         for (i = 0; i < arity; i++) {
1088                 ir_node *ret;
1089                 ret = get_Block_cfgpred(end_bl, i);
1090                 if (is_Return(ret)) {
1091                         cf_pred[n_ret] = new_r_Jmp(irg, get_nodes_block(ret));
1092                         n_ret++;
1093                 }
1094         }
1095         set_irn_in(post_bl, n_ret, cf_pred);
1096
1097         /* -- Build a Tuple for all results of the method.
1098            Add Phi node if there was more than one Return.  -- */
1099         turn_into_tuple(post_call, pn_Call_max);
1100         /* First the Memory-Phi */
1101         n_ret = 0;
1102         for (i = 0; i < arity; i++) {
1103                 ret = get_Block_cfgpred(end_bl, i);
1104                 if (is_Return(ret)) {
1105                         cf_pred[n_ret] = get_Return_mem(ret);
1106                         n_ret++;
1107                 }
1108         }
1109         phi = new_Phi(n_ret, cf_pred, mode_M);
1110         set_Tuple_pred(call, pn_Call_M_regular, phi);
1111         /* Conserve Phi-list for further inlinings -- but might be optimized */
1112         if (get_nodes_block(phi) == post_bl) {
1113                 set_irn_link(phi, get_irn_link(post_bl));
1114                 set_irn_link(post_bl, phi);
1115         }
1116         /* Now the real results */
1117         if (n_res > 0) {
1118                 for (j = 0; j < n_res; j++) {
1119                         n_ret = 0;
1120                         for (i = 0; i < arity; i++) {
1121                                 ret = get_Block_cfgpred(end_bl, i);
1122                                 if (is_Return(ret)) {
1123                                         cf_pred[n_ret] = get_Return_res(ret, j);
1124                                         n_ret++;
1125                                 }
1126                         }
1127                         if (n_ret > 0)
1128                                 phi = new_Phi(n_ret, cf_pred, get_irn_mode(cf_pred[0]));
1129                         else
1130                                 phi = new_Bad();
1131                         res_pred[j] = phi;
1132                         /* Conserve Phi-list for further inlinings -- but might be optimized */
1133                         if (get_nodes_block(phi) == post_bl) {
1134                                 set_Phi_next(phi, get_Block_phis(post_bl));
1135                                 set_Block_phis(post_bl, phi);
1136                         }
1137                 }
1138                 set_Tuple_pred(call, pn_Call_T_result, new_Tuple(n_res, res_pred));
1139         } else {
1140                 set_Tuple_pred(call, pn_Call_T_result, new_Bad());
1141         }
1142         /* handle the regular call */
1143         set_Tuple_pred(call, pn_Call_X_regular, new_Jmp());
1144
1145         /* For now, we cannot inline calls with value_base */
1146         set_Tuple_pred(call, pn_Call_P_value_res_base, new_Bad());
1147
1148         /* Finally the exception control flow.
1149            We have two (three) possible situations:
1150            First if the Call branches to an exception handler: We need to add a Phi node to
1151            collect the memory containing the exception objects.  Further we need
1152            to add another block to get a correct representation of this Phi.  To
1153            this block we add a Jmp that resolves into the X output of the Call
1154            when the Call is turned into a tuple.
1155            Second the Call branches to End, the exception is not handled.  Just
1156            add all inlined exception branches to the End node.
1157            Third: there is no Exception edge at all. Handle as case two. */
1158         if (exc_handling == exc_handler) {
1159                 n_exc = 0;
1160                 for (i = 0; i < arity; i++) {
1161                         ir_node *ret, *irn;
1162                         ret = get_Block_cfgpred(end_bl, i);
1163                         irn = skip_Proj(ret);
1164                         if (is_fragile_op(irn) || is_Raise(irn)) {
1165                                 cf_pred[n_exc] = ret;
1166                                 ++n_exc;
1167                         }
1168                 }
1169                 if (n_exc > 0) {
1170                         new_Block(n_exc, cf_pred);      /* watch it: current_block is changed! */
1171                         set_Tuple_pred(call, pn_Call_X_except, new_Jmp());
1172                         /* The Phi for the memories with the exception objects */
1173                         n_exc = 0;
1174                         for (i = 0; i < arity; i++) {
1175                                 ir_node *ret;
1176                                 ret = skip_Proj(get_Block_cfgpred(end_bl, i));
1177                                 if (is_Call(ret)) {
1178                                         cf_pred[n_exc] = new_r_Proj(irg, get_nodes_block(ret), ret, mode_M, 3);
1179                                         n_exc++;
1180                                 } else if (is_fragile_op(ret)) {
1181                                         /* We rely that all cfops have the memory output at the same position. */
1182                                         cf_pred[n_exc] = new_r_Proj(irg, get_nodes_block(ret), ret, mode_M, 0);
1183                                         n_exc++;
1184                                 } else if (is_Raise(ret)) {
1185                                         cf_pred[n_exc] = new_r_Proj(irg, get_nodes_block(ret), ret, mode_M, 1);
1186                                         n_exc++;
1187                                 }
1188                         }
1189                         set_Tuple_pred(call, pn_Call_M_except, new_Phi(n_exc, cf_pred, mode_M));
1190                 } else {
1191                         set_Tuple_pred(call, pn_Call_X_except, new_Bad());
1192                         set_Tuple_pred(call, pn_Call_M_except, new_Bad());
1193                 }
1194         } else {
1195                 ir_node *main_end_bl;
1196                 int main_end_bl_arity;
1197                 ir_node **end_preds;
1198
1199                 /* assert(exc_handling == 1 || no exceptions. ) */
1200                 n_exc = 0;
1201                 for (i = 0; i < arity; i++) {
1202                         ir_node *ret = get_Block_cfgpred(end_bl, i);
1203                         ir_node *irn = skip_Proj(ret);
1204
1205                         if (is_fragile_op(irn) || is_Raise(irn)) {
1206                                 cf_pred[n_exc] = ret;
1207                                 n_exc++;
1208                         }
1209                 }
1210                 main_end_bl       = get_irg_end_block(irg);
1211                 main_end_bl_arity = get_irn_arity(main_end_bl);
1212                 end_preds         = XMALLOCN(ir_node*, n_exc + main_end_bl_arity);
1213
1214                 for (i = 0; i < main_end_bl_arity; ++i)
1215                         end_preds[i] = get_irn_n(main_end_bl, i);
1216                 for (i = 0; i < n_exc; ++i)
1217                         end_preds[main_end_bl_arity + i] = cf_pred[i];
1218                 set_irn_in(main_end_bl, n_exc + main_end_bl_arity, end_preds);
1219                 set_Tuple_pred(call, pn_Call_X_except,  new_Bad());
1220                 set_Tuple_pred(call, pn_Call_M_except,  new_Bad());
1221                 free(end_preds);
1222         }
1223         free(res_pred);
1224         free(cf_pred);
1225
1226         /* --  Turn CSE back on. -- */
1227         set_optimize(rem_opt);
1228         current_ir_graph = rem;
1229
1230         return 1;
1231 }
1232
1233 /********************************************************************/
1234 /* Apply inlining to small methods.                                 */
1235 /********************************************************************/
1236
1237 static struct obstack  temp_obst;
1238
1239 /** Represents a possible inlinable call in a graph. */
1240 typedef struct _call_entry {
1241         ir_node    *call;       /**< The Call node. */
1242         ir_graph   *callee;     /**< The callee IR-graph. */
1243         list_head  list;        /**< List head for linking the next one. */
1244         int        loop_depth;  /**< The loop depth of this call. */
1245         int        benefice;    /**< The calculated benefice of this call. */
1246         unsigned   local_adr:1; /**< Set if this call gets an address of a local variable. */
1247         unsigned   all_const:1; /**< Set if this call has only constant parameters. */
1248 } call_entry;
1249
1250 /**
1251  * environment for inlining small irgs
1252  */
1253 typedef struct _inline_env_t {
1254         struct obstack obst;  /**< An obstack where call_entries are allocated on. */
1255         list_head      calls; /**< The call entry list. */
1256 } inline_env_t;
1257
1258 /**
1259  * Returns the irg called from a Call node. If the irg is not
1260  * known, NULL is returned.
1261  *
1262  * @param call  the call node
1263  */
1264 static ir_graph *get_call_called_irg(ir_node *call) {
1265         ir_node *addr;
1266
1267         addr = get_Call_ptr(call);
1268         if (is_Global(addr)) {
1269                 ir_entity *ent = get_Global_entity(addr);
1270                 return get_entity_irg(ent);
1271         }
1272
1273         return NULL;
1274 }
1275
1276 /**
1277  * Walker: Collect all calls to known graphs inside a graph.
1278  */
1279 static void collect_calls(ir_node *call, void *env) {
1280         (void) env;
1281         if (is_Call(call)) {
1282                 ir_graph *called_irg = get_call_called_irg(call);
1283
1284                 if (called_irg != NULL) {
1285                         /* The Call node calls a locally defined method.  Remember to inline. */
1286                         inline_env_t *ienv  = env;
1287                         call_entry   *entry = obstack_alloc(&ienv->obst, sizeof(*entry));
1288                         entry->call       = call;
1289                         entry->callee     = called_irg;
1290                         entry->loop_depth = 0;
1291                         entry->benefice   = 0;
1292                         entry->local_adr  = 0;
1293                         entry->all_const  = 0;
1294
1295                         list_add_tail(&entry->list, &ienv->calls);
1296                 }
1297         }
1298 }
1299
1300 /**
1301  * Inlines all small methods at call sites where the called address comes
1302  * from a Const node that references the entity representing the called
1303  * method.
1304  * The size argument is a rough measure for the code size of the method:
1305  * Methods where the obstack containing the firm graph is smaller than
1306  * size are inlined.
1307  */
1308 void inline_small_irgs(ir_graph *irg, int size) {
1309         ir_graph *rem = current_ir_graph;
1310         inline_env_t env;
1311         call_entry *entry;
1312
1313         current_ir_graph = irg;
1314         /* Handle graph state */
1315         assert(get_irg_phase_state(irg) != phase_building);
1316         free_callee_info(irg);
1317
1318         /* Find Call nodes to inline.
1319            (We can not inline during a walk of the graph, as inlining the same
1320            method several times changes the visited flag of the walked graph:
1321            after the first inlining visited of the callee equals visited of
1322            the caller.  With the next inlining both are increased.) */
1323         obstack_init(&env.obst);
1324         INIT_LIST_HEAD(&env.calls);
1325         irg_walk_graph(irg, NULL, collect_calls, &env);
1326
1327         if (! list_empty(&env.calls)) {
1328                 /* There are calls to inline */
1329                 ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
1330                 collect_phiprojs(irg);
1331
1332                 list_for_each_entry(call_entry, entry, &env.calls, list) {
1333                         ir_graph            *callee = entry->callee;
1334                         irg_inline_property prop    = get_irg_inline_property(callee);
1335
1336                         if (prop == irg_inline_forbidden || get_irg_additional_properties(callee) & mtp_property_weak) {
1337                                 /* do not inline forbidden / weak graphs */
1338                                 continue;
1339                         }
1340
1341                         if (prop >= irg_inline_forced ||
1342                             _obstack_memory_used(callee->obst) - (int)obstack_room(callee->obst) < size) {
1343                                 inline_method(entry->call, callee);
1344                         }
1345                 }
1346                 ir_free_resources(irg, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
1347         }
1348         obstack_free(&env.obst, NULL);
1349         current_ir_graph = rem;
1350 }
1351
1352 /**
1353  * Environment for inlining irgs.
1354  */
1355 typedef struct {
1356         list_head calls;             /**< List of of all call nodes in this graph. */
1357         unsigned  *local_weights;    /**< Once allocated, the beneficial weight for transmitting local addresses. */
1358         unsigned  n_nodes;           /**< Number of nodes in graph except Id, Tuple, Proj, Start, End. */
1359         unsigned  n_blocks;          /**< Number of Blocks in graph without Start and End block. */
1360         unsigned  n_nodes_orig;      /**< for statistics */
1361         unsigned  n_call_nodes;      /**< Number of Call nodes in the graph. */
1362         unsigned  n_call_nodes_orig; /**< for statistics */
1363         unsigned  n_callers;         /**< Number of known graphs that call this graphs. */
1364         unsigned  n_callers_orig;    /**< for statistics */
1365         unsigned  got_inline:1;      /**< Set, if at least one call inside this graph was inlined. */
1366         unsigned  local_vars:1;      /**< Set, if an inlined function got the address of a local variable. */
1367         unsigned  recursive:1;       /**< Set, if this function is self recursive. */
1368 } inline_irg_env;
1369
1370 /**
1371  * Allocate a new environment for inlining.
1372  */
1373 static inline_irg_env *alloc_inline_irg_env(void) {
1374         inline_irg_env *env    = obstack_alloc(&temp_obst, sizeof(*env));
1375         INIT_LIST_HEAD(&env->calls);
1376         env->local_weights     = NULL;
1377         env->n_nodes           = -2; /* do not count count Start, End */
1378         env->n_blocks          = -2; /* do not count count Start, End Block */
1379         env->n_nodes_orig      = -2; /* do not count Start, End */
1380         env->n_call_nodes      = 0;
1381         env->n_call_nodes_orig = 0;
1382         env->n_callers         = 0;
1383         env->n_callers_orig    = 0;
1384         env->got_inline        = 0;
1385         env->local_vars        = 0;
1386         env->recursive         = 0;
1387         return env;
1388 }
1389
1390 typedef struct walker_env {
1391         inline_irg_env *x;     /**< the inline environment */
1392         char ignore_runtime;   /**< the ignore runtime flag */
1393         char ignore_callers;   /**< if set, do change callers data */
1394 } wenv_t;
1395
1396 /**
1397  * post-walker: collect all calls in the inline-environment
1398  * of a graph and sum some statistics.
1399  */
1400 static void collect_calls2(ir_node *call, void *ctx) {
1401         wenv_t         *env = ctx;
1402         inline_irg_env *x = env->x;
1403         ir_opcode      code = get_irn_opcode(call);
1404         ir_graph       *callee;
1405         call_entry     *entry;
1406
1407         /* count meaningful nodes in irg */
1408         if (code != iro_Proj && code != iro_Tuple && code != iro_Sync) {
1409                 if (code != iro_Block) {
1410                         ++x->n_nodes;
1411                         ++x->n_nodes_orig;
1412                 } else {
1413                         ++x->n_blocks;
1414                 }
1415         }
1416
1417         if (code != iro_Call) return;
1418
1419         /* check, if it's a runtime call */
1420         if (env->ignore_runtime) {
1421                 ir_node *symc = get_Call_ptr(call);
1422
1423                 if (is_Global(symc)) {
1424                         ir_entity *ent = get_Global_entity(symc);
1425
1426                         if (get_entity_additional_properties(ent) & mtp_property_runtime)
1427                                 return;
1428                 }
1429         }
1430
1431         /* collect all call nodes */
1432         ++x->n_call_nodes;
1433         ++x->n_call_nodes_orig;
1434
1435         callee = get_call_called_irg(call);
1436         if (callee != NULL) {
1437                 if (! env->ignore_callers) {
1438                         inline_irg_env *callee_env = get_irg_link(callee);
1439                         /* count all static callers */
1440                         ++callee_env->n_callers;
1441                         ++callee_env->n_callers_orig;
1442                 }
1443                 if (callee == current_ir_graph)
1444                         x->recursive = 1;
1445
1446                 /* link it in the list of possible inlinable entries */
1447                 entry = obstack_alloc(&temp_obst, sizeof(*entry));
1448                 entry->call       = call;
1449                 entry->callee     = callee;
1450                 entry->loop_depth = get_irn_loop(get_nodes_block(call))->depth;
1451                 entry->benefice   = 0;
1452                 entry->local_adr  = 0;
1453                 entry->all_const  = 0;
1454
1455                 list_add_tail(&entry->list, &x->calls);
1456         }
1457 }
1458
1459 /**
1460  * Returns TRUE if the number of callers is 0 in the irg's environment,
1461  * hence this irg is a leave.
1462  */
1463 inline static int is_leave(ir_graph *irg) {
1464         inline_irg_env *env = get_irg_link(irg);
1465         return env->n_call_nodes == 0;
1466 }
1467
1468 /**
1469  * Returns TRUE if the number of nodes in the callee is
1470  * smaller then size in the irg's environment.
1471  */
1472 inline static int is_smaller(ir_graph *callee, unsigned size) {
1473         inline_irg_env *env = get_irg_link(callee);
1474         return env->n_nodes < size;
1475 }
1476
1477 /**
1478  * Duplicate a call entry.
1479  *
1480  * @param entry     the original entry to duplicate
1481  * @param new_call  the new call node
1482  * @param loop_depth_delta
1483  *                  delta value for the loop depth
1484  */
1485 static call_entry *duplicate_call_entry(const call_entry *entry,
1486                                         ir_node *new_call, int loop_depth_delta) {
1487         call_entry *nentry = obstack_alloc(&temp_obst, sizeof(*nentry));
1488         nentry->call       = new_call;
1489         nentry->callee     = entry->callee;
1490         nentry->benefice   = entry->benefice;
1491         nentry->loop_depth = entry->loop_depth + loop_depth_delta;
1492         nentry->local_adr  = entry->local_adr;
1493         nentry->all_const  = entry->all_const;
1494
1495         return nentry;
1496 }
1497
1498 /**
1499  * Append all call nodes of the source environment to the nodes of in the destination
1500  * environment.
1501  *
1502  * @param dst         destination environment
1503  * @param src         source environment
1504  * @param loop_depth  the loop depth of the call that is replaced by the src list
1505  */
1506 static void append_call_list(inline_irg_env *dst, inline_irg_env *src, int loop_depth) {
1507         call_entry *entry, *nentry;
1508
1509         /* Note that the src list points to Call nodes in the inlined graph, but
1510            we need Call nodes in our graph. Luckily the inliner leaves this information
1511            in the link field. */
1512         list_for_each_entry(call_entry, entry, &src->calls, list) {
1513                 nentry = duplicate_call_entry(entry, get_irn_link(entry->call), loop_depth);
1514                 list_add_tail(&nentry->list, &dst->calls);
1515         }
1516         dst->n_call_nodes += src->n_call_nodes;
1517         dst->n_nodes      += src->n_nodes;
1518 }
1519
1520 /*
1521  * Inlines small leave methods at call sites where the called address comes
1522  * from a Const node that references the entity representing the called
1523  * method.
1524  * The size argument is a rough measure for the code size of the method:
1525  * Methods where the obstack containing the firm graph is smaller than
1526  * size are inlined.
1527  */
1528 void inline_leave_functions(unsigned maxsize, unsigned leavesize,
1529                             unsigned size, int ignore_runtime)
1530 {
1531         inline_irg_env   *env;
1532         ir_graph         *irg;
1533         int              i, n_irgs;
1534         ir_graph         *rem;
1535         int              did_inline;
1536         wenv_t           wenv;
1537         call_entry       *entry, *next;
1538         const call_entry *centry;
1539         pmap             *copied_graphs;
1540         pmap_entry       *pm_entry;
1541
1542         rem = current_ir_graph;
1543         obstack_init(&temp_obst);
1544
1545         /* a map for the copied graphs, used to inline recursive calls */
1546         copied_graphs = pmap_create();
1547
1548         /* extend all irgs by a temporary data structure for inlining. */
1549         n_irgs = get_irp_n_irgs();
1550         for (i = 0; i < n_irgs; ++i)
1551                 set_irg_link(get_irp_irg(i), alloc_inline_irg_env());
1552
1553         /* Pre-compute information in temporary data structure. */
1554         wenv.ignore_runtime = ignore_runtime;
1555         wenv.ignore_callers = 0;
1556         for (i = 0; i < n_irgs; ++i) {
1557                 ir_graph *irg = get_irp_irg(i);
1558
1559                 assert(get_irg_phase_state(irg) != phase_building);
1560                 free_callee_info(irg);
1561
1562                 assure_cf_loop(irg);
1563                 wenv.x = get_irg_link(irg);
1564                 irg_walk_graph(irg, NULL, collect_calls2, &wenv);
1565         }
1566
1567         /* -- and now inline. -- */
1568
1569         /* Inline leaves recursively -- we might construct new leaves. */
1570         do {
1571                 did_inline = 0;
1572
1573                 for (i = 0; i < n_irgs; ++i) {
1574                         ir_node *call;
1575                         int phiproj_computed = 0;
1576
1577                         current_ir_graph = get_irp_irg(i);
1578                         env              = get_irg_link(current_ir_graph);
1579
1580                         ir_reserve_resources(current_ir_graph, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
1581                         list_for_each_entry_safe(call_entry, entry, next, &env->calls, list) {
1582                                 ir_graph            *callee;
1583                                 irg_inline_property  prop;
1584
1585                                 if (env->n_nodes > maxsize)
1586                                         break;
1587
1588                                 call   = entry->call;
1589                                 callee = entry->callee;
1590
1591                                 prop = get_irg_inline_property(callee);
1592                                 if (prop == irg_inline_forbidden || get_irg_additional_properties(callee) & mtp_property_weak) {
1593                                         /* do not inline forbidden / weak graphs */
1594                                         continue;
1595                                 }
1596
1597                                 if (is_leave(callee) && (
1598                                     is_smaller(callee, leavesize) || prop >= irg_inline_forced)) {
1599                                         if (!phiproj_computed) {
1600                                                 phiproj_computed = 1;
1601                                                 collect_phiprojs(current_ir_graph);
1602                                         }
1603                                         did_inline = inline_method(call, callee);
1604
1605                                         if (did_inline) {
1606                                                 inline_irg_env *callee_env = get_irg_link(callee);
1607
1608                                                 /* call was inlined, Phi/Projs for current graph must be recomputed */
1609                                                 phiproj_computed = 0;
1610
1611                                                 /* Do some statistics */
1612                                                 env->got_inline = 1;
1613                                                 --env->n_call_nodes;
1614                                                 env->n_nodes += callee_env->n_nodes;
1615                                                 --callee_env->n_callers;
1616
1617                                                 /* remove this call from the list */
1618                                                 list_del(&entry->list);
1619                                                 continue;
1620                                         }
1621                                 }
1622                         }
1623                         ir_free_resources(current_ir_graph, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
1624                 }
1625         } while (did_inline);
1626
1627         /* inline other small functions. */
1628         for (i = 0; i < n_irgs; ++i) {
1629                 ir_node *call;
1630                 int phiproj_computed = 0;
1631
1632                 current_ir_graph = get_irp_irg(i);
1633                 env              = get_irg_link(current_ir_graph);
1634
1635                 ir_reserve_resources(current_ir_graph, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
1636
1637                 /* note that the list of possible calls is updated during the process */
1638                 list_for_each_entry_safe(call_entry, entry, next, &env->calls, list) {
1639                         irg_inline_property prop;
1640                         ir_graph            *callee;
1641                         pmap_entry          *e;
1642
1643                         call   = entry->call;
1644                         callee = entry->callee;
1645
1646                         prop = get_irg_inline_property(callee);
1647                         if (prop == irg_inline_forbidden || get_irg_additional_properties(callee) & mtp_property_weak) {
1648                                 /* do not inline forbidden / weak graphs */
1649                                 continue;
1650                         }
1651
1652                         e = pmap_find(copied_graphs, callee);
1653                         if (e != NULL) {
1654                                 /*
1655                                  * Remap callee if we have a copy.
1656                                  * FIXME: Should we do this only for recursive Calls ?
1657                                  */
1658                                 callee = e->value;
1659                         }
1660
1661                         if (prop >= irg_inline_forced ||
1662                             (is_smaller(callee, size) && env->n_nodes < maxsize) /* small function */) {
1663                                 if (current_ir_graph == callee) {
1664                                         /*
1665                                          * Recursive call: we cannot directly inline because we cannot walk
1666                                          * the graph and change it. So we have to make a copy of the graph
1667                                          * first.
1668                                          */
1669
1670                                         inline_irg_env *callee_env;
1671                                         ir_graph       *copy;
1672
1673                                         ir_free_resources(current_ir_graph, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
1674
1675                                         /*
1676                                          * No copy yet, create one.
1677                                          * Note that recursive methods are never leaves, so it is sufficient
1678                                          * to test this condition here.
1679                                          */
1680                                         copy = create_irg_copy(callee);
1681
1682                                         /* create_irg_copy() destroys the Proj links, recompute them */
1683                                         phiproj_computed = 0;
1684
1685                                         ir_reserve_resources(current_ir_graph, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
1686
1687                                         /* allocate new environment */
1688                                         callee_env = alloc_inline_irg_env();
1689                                         set_irg_link(copy, callee_env);
1690
1691                                         assure_cf_loop(copy);
1692                                         wenv.x              = callee_env;
1693                                         wenv.ignore_callers = 1;
1694                                         irg_walk_graph(copy, NULL, collect_calls2, &wenv);
1695
1696                                         /*
1697                                          * Enter the entity of the original graph. This is needed
1698                                          * for inline_method(). However, note that ent->irg still points
1699                                          * to callee, NOT to copy.
1700                                          */
1701                                         set_irg_entity(copy, get_irg_entity(callee));
1702
1703                                         pmap_insert(copied_graphs, callee, copy);
1704                                         callee = copy;
1705
1706                                         /* we have only one caller: the original graph */
1707                                         callee_env->n_callers      = 1;
1708                                         callee_env->n_callers_orig = 1;
1709                                 }
1710                                 if (! phiproj_computed) {
1711                                         phiproj_computed = 1;
1712                                         collect_phiprojs(current_ir_graph);
1713                                 }
1714                                 did_inline = inline_method(call, callee);
1715                                 if (did_inline) {
1716                                         inline_irg_env *callee_env = (inline_irg_env *)get_irg_link(callee);
1717
1718                                         /* call was inlined, Phi/Projs for current graph must be recomputed */
1719                                         phiproj_computed = 0;
1720
1721                                         /* callee was inline. Append it's call list. */
1722                                         env->got_inline = 1;
1723                                         --env->n_call_nodes;
1724                                         append_call_list(env, callee_env, entry->loop_depth);
1725                                         --callee_env->n_callers;
1726
1727                                         /* after we have inlined callee, all called methods inside callee
1728                                            are now called once more */
1729                                         list_for_each_entry(call_entry, centry, &callee_env->calls, list) {
1730                                                 inline_irg_env *penv = get_irg_link(centry->callee);
1731                                                 ++penv->n_callers;
1732                                         }
1733
1734                                         /* remove this call from the list */
1735                                         list_del(&entry->list);
1736                                         continue;
1737                                 }
1738                         }
1739                 }
1740                 ir_free_resources(current_ir_graph, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
1741         }
1742
1743         for (i = 0; i < n_irgs; ++i) {
1744                 irg = get_irp_irg(i);
1745                 env = get_irg_link(irg);
1746
1747                 if (env->got_inline) {
1748                         optimize_graph_df(irg);
1749                         optimize_cf(irg);
1750                 }
1751                 if (env->got_inline || (env->n_callers_orig != env->n_callers)) {
1752                         DB((dbg, LEVEL_1, "Nodes:%3d ->%3d, calls:%3d ->%3d, callers:%3d ->%3d, -- %s\n",
1753                         env->n_nodes_orig, env->n_nodes, env->n_call_nodes_orig, env->n_call_nodes,
1754                         env->n_callers_orig, env->n_callers,
1755                         get_entity_name(get_irg_entity(irg))));
1756                 }
1757         }
1758
1759         /* kill the copied graphs: we don't need them anymore */
1760         foreach_pmap(copied_graphs, pm_entry) {
1761                 ir_graph *copy = pm_entry->value;
1762
1763                 /* reset the entity, otherwise it will be deleted in the next step ... */
1764                 set_irg_entity(copy, NULL);
1765                 free_ir_graph(copy);
1766         }
1767         pmap_destroy(copied_graphs);
1768
1769         obstack_free(&temp_obst, NULL);
1770         current_ir_graph = rem;
1771 }
1772
1773 /**
1774  * Calculate the parameter weights for transmitting the address of a local variable.
1775  */
1776 static unsigned calc_method_local_weight(ir_node *arg) {
1777         int      i, j, k;
1778         unsigned v, weight = 0;
1779
1780         for (i = get_irn_n_outs(arg) - 1; i >= 0; --i) {
1781                 ir_node *succ = get_irn_out(arg, i);
1782
1783                 switch (get_irn_opcode(succ)) {
1784                 case iro_Load:
1785                 case iro_Store:
1786                         /* Loads and Store can be removed */
1787                         weight += 3;
1788                         break;
1789                 case iro_Sel:
1790                         /* check if all args are constant */
1791                         for (j = get_Sel_n_indexs(succ) - 1; j >= 0; --j) {
1792                                 ir_node *idx = get_Sel_index(succ, j);
1793                                 if (! is_Const(idx))
1794                                         return 0;
1795                         }
1796                         /* Check users on this Sel. Note: if a 0 is returned here, there was
1797                            some unsupported node. */
1798                         v = calc_method_local_weight(succ);
1799                         if (v == 0)
1800                                 return 0;
1801                         /* we can kill one Sel with constant indexes, this is cheap */
1802                         weight += v + 1;
1803                         break;
1804                 case iro_Id:
1805                         /* when looking backward we might find Id nodes */
1806                         weight += calc_method_local_weight(succ);
1807                         break;
1808                 case iro_Tuple:
1809                         /* unoptimized tuple */
1810                         for (j = get_Tuple_n_preds(succ) - 1; j >= 0; --j) {
1811                                 ir_node *pred = get_Tuple_pred(succ, j);
1812                                 if (pred == arg) {
1813                                         /* look for Proj(j) */
1814                                         for (k = get_irn_n_outs(succ) - 1; k >= 0; --k) {
1815                                                 ir_node *succ_succ = get_irn_out(succ, k);
1816                                                 if (is_Proj(succ_succ)) {
1817                                                         if (get_Proj_proj(succ_succ) == j) {
1818                                                                 /* found */
1819                                                                 weight += calc_method_local_weight(succ_succ);
1820                                                         }
1821                                                 } else {
1822                                                         /* this should NOT happen */
1823                                                         return 0;
1824                                                 }
1825                                         }
1826                                 }
1827                         }
1828                         break;
1829                 default:
1830                         /* any other node: unsupported yet or bad. */
1831                         return 0;
1832                 }
1833         }
1834         return weight;
1835 }
1836
1837 /**
1838  * Calculate the parameter weights for transmitting the address of a local variable.
1839  */
1840 static void analyze_irg_local_weights(inline_irg_env *env, ir_graph *irg) {
1841         ir_entity *ent = get_irg_entity(irg);
1842         ir_type  *mtp;
1843         int      nparams, i, proj_nr;
1844         ir_node  *irg_args, *arg;
1845
1846         mtp      = get_entity_type(ent);
1847         nparams  = get_method_n_params(mtp);
1848
1849         /* allocate a new array. currently used as 'analysed' flag */
1850         env->local_weights = NEW_ARR_D(unsigned, &temp_obst, nparams);
1851
1852         /* If the method haven't parameters we have nothing to do. */
1853         if (nparams <= 0)
1854                 return;
1855
1856         assure_irg_outs(irg);
1857         irg_args = get_irg_args(irg);
1858         for (i = get_irn_n_outs(irg_args) - 1; i >= 0; --i) {
1859                 arg     = get_irn_out(irg_args, i);
1860                 proj_nr = get_Proj_proj(arg);
1861                 env->local_weights[proj_nr] = calc_method_local_weight(arg);
1862         }
1863 }
1864
1865 /**
1866  * Calculate the benefice for transmitting an local variable address.
1867  * After inlining, the local variable might be transformed into a
1868  * SSA variable by scalar_replacement().
1869  */
1870 static unsigned get_method_local_adress_weight(ir_graph *callee, int pos) {
1871         inline_irg_env *env = get_irg_link(callee);
1872
1873         if (env->local_weights != NULL) {
1874                 if (pos < ARR_LEN(env->local_weights))
1875                         return env->local_weights[pos];
1876                 return 0;
1877         }
1878
1879         analyze_irg_local_weights(env, callee);
1880
1881         if (pos < ARR_LEN(env->local_weights))
1882                 return env->local_weights[pos];
1883         return 0;
1884 }
1885
1886 /**
1887  * Calculate a benefice value for inlining the given call.
1888  *
1889  * @param call       the call node we have to inspect
1890  * @param callee     the called graph
1891  */
1892 static int calc_inline_benefice(call_entry *entry, ir_graph *callee)
1893 {
1894         ir_node   *call = entry->call;
1895         ir_entity *ent  = get_irg_entity(callee);
1896         ir_node   *frame_ptr;
1897         ir_type   *mtp;
1898         int       weight = 0;
1899         int       i, n_params, all_const;
1900         unsigned  cc, v;
1901         irg_inline_property prop;
1902
1903         inline_irg_env *callee_env;
1904
1905         prop = get_irg_inline_property(callee);
1906         if (prop == irg_inline_forbidden) {
1907                 DB((dbg, LEVEL_2, "In %+F Call to %+F: inlining forbidden\n",
1908                     call, callee));
1909                 return entry->benefice = INT_MIN;
1910         }
1911
1912         if (get_irg_additional_properties(callee) & (mtp_property_noreturn | mtp_property_weak)) {
1913                 DB((dbg, LEVEL_2, "In %+F Call to %+F: not inlining noreturn or weak\n",
1914                     call, callee));
1915                 return entry->benefice = INT_MIN;
1916         }
1917
1918         /* costs for every passed parameter */
1919         n_params = get_Call_n_params(call);
1920         mtp      = get_entity_type(ent);
1921         cc       = get_method_calling_convention(mtp);
1922         if (cc & cc_reg_param) {
1923                 /* register parameter, smaller costs for register parameters */
1924                 int max_regs = cc & ~cc_bits;
1925
1926                 if (max_regs < n_params)
1927                         weight += max_regs * 2 + (n_params - max_regs) * 5;
1928                 else
1929                         weight += n_params * 2;
1930         } else {
1931                 /* parameters are passed an stack */
1932                 weight += 5 * n_params;
1933         }
1934
1935         /* constant parameters improve the benefice */
1936         frame_ptr = get_irg_frame(current_ir_graph);
1937         all_const = 1;
1938         for (i = 0; i < n_params; ++i) {
1939                 ir_node *param = get_Call_param(call, i);
1940
1941                 if (is_Const(param)) {
1942                         weight += get_method_param_weight(ent, i);
1943                 } else {
1944                         all_const = 0;
1945                         if (is_SymConst(param))
1946                                 weight += get_method_param_weight(ent, i);
1947                         else if (is_Sel(param) && get_Sel_ptr(param) == frame_ptr) {
1948                                 /*
1949                                  * An address of a local variable is transmitted. After
1950                                  * inlining, scalar_replacement might be able to remove the
1951                                  * local variable, so honor this.
1952                                  */
1953                                 v = get_method_local_adress_weight(callee, i);
1954                                 weight += v;
1955                                 if (v > 0)
1956                                         entry->local_adr = 1;
1957                         }
1958                 }
1959         }
1960         entry->all_const = all_const;
1961
1962         callee_env = get_irg_link(callee);
1963         if (callee_env->n_callers == 1 &&
1964             callee != current_ir_graph &&
1965                 get_entity_visibility(ent) == visibility_local) {
1966                 weight += 700;
1967         }
1968
1969         /* give a bonus for functions with one block */
1970         if (callee_env->n_blocks == 1)
1971                 weight = weight * 3 / 2;
1972
1973         /* and one for small non-recursive functions: we want them to be inlined in mostly every case */
1974         if (callee_env->n_nodes < 30 && !callee_env->recursive)
1975                 weight += 2000;
1976
1977         /* and finally for leaves: they do not increase the register pressure
1978            because of callee safe registers */
1979         if (callee_env->n_call_nodes == 0)
1980                 weight += 400;
1981
1982         /** it's important to inline inner loops first */
1983         if (entry->loop_depth > 30)
1984                 weight += 30 * 1024;
1985         else
1986                 weight += entry->loop_depth * 1024;
1987
1988         /*
1989          * All arguments constant is probably a good sign, give an extra bonus
1990          */
1991         if (all_const)
1992                 weight += 1024;
1993
1994         return entry->benefice = weight;
1995 }
1996
1997 static ir_graph **irgs;
1998 static int      last_irg;
1999
2000 /**
2001  * Callgraph walker, collect all visited graphs.
2002  */
2003 static void callgraph_walker(ir_graph *irg, void *data) {
2004         (void) data;
2005         irgs[last_irg++] = irg;
2006 }
2007
2008 /**
2009  * Creates an inline order for all graphs.
2010  *
2011  * @return the list of graphs.
2012  */
2013 static ir_graph **create_irg_list(void) {
2014         ir_entity **free_methods;
2015         int       arr_len;
2016         int       n_irgs = get_irp_n_irgs();
2017
2018         cgana(&arr_len, &free_methods);
2019         xfree(free_methods);
2020
2021         compute_callgraph();
2022
2023         last_irg = 0;
2024         irgs     = XMALLOCNZ(ir_graph*, n_irgs);
2025
2026         callgraph_walk(NULL, callgraph_walker, NULL);
2027         assert(n_irgs == last_irg);
2028
2029         return irgs;
2030 }
2031
2032 /**
2033  * Push a call onto the priority list if its benefice is big enough.
2034  *
2035  * @param pqueue   the priority queue of calls
2036  * @param call     the call entry
2037  * @param inlien_threshold
2038  *                 the threshold value
2039  */
2040 static void maybe_push_call(pqueue_t *pqueue, call_entry *call,
2041                             int inline_threshold)
2042 {
2043         ir_graph            *callee  = call->callee;
2044         irg_inline_property prop     = get_irg_inline_property(callee);
2045         int                 benefice = calc_inline_benefice(call, callee);
2046
2047         DB((dbg, LEVEL_2, "In %+F Call %+F to %+F has benefice %d\n",
2048             get_irn_irg(call->call), call->call, callee, benefice));
2049
2050         if (prop < irg_inline_forced && benefice < inline_threshold) {
2051                 return;
2052         }
2053
2054         pqueue_put(pqueue, call, benefice);
2055 }
2056
2057 /**
2058  * Try to inline calls into a graph.
2059  *
2060  * @param irg      the graph into which we inline
2061  * @param maxsize  do NOT inline if the size of irg gets
2062  *                 bigger than this amount
2063  * @param inline_threshold
2064  *                 threshold value for inline decision
2065  * @param copied_graphs
2066  *                 map containing copied of recursive graphs
2067  */
2068 static void inline_into(ir_graph *irg, unsigned maxsize,
2069                         int inline_threshold, pmap *copied_graphs)
2070 {
2071         int            phiproj_computed = 0;
2072         inline_irg_env *env = get_irg_link(irg);
2073         call_entry     *curr_call;
2074         wenv_t         wenv;
2075         pqueue_t       *pqueue;
2076
2077         if (env->n_call_nodes == 0)
2078                 return;
2079
2080         if (env->n_nodes > maxsize) {
2081                 DB((dbg, LEVEL_2, "%+F: too big (%d)\n", irg, env->n_nodes));
2082                 return;
2083         }
2084
2085         current_ir_graph = irg;
2086         ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
2087
2088         /* put irgs into the pqueue */
2089         pqueue = new_pqueue();
2090
2091         list_for_each_entry(call_entry, curr_call, &env->calls, list) {
2092                 assert(is_Call(curr_call->call));
2093                 maybe_push_call(pqueue, curr_call, inline_threshold);
2094         }
2095
2096         /* note that the list of possible calls is updated during the process */
2097         while (!pqueue_empty(pqueue)) {
2098                 int                 did_inline;
2099                 call_entry          *curr_call  = pqueue_pop_front(pqueue);
2100                 ir_graph            *callee     = curr_call->callee;
2101                 ir_node             *call_node  = curr_call->call;
2102                 inline_irg_env      *callee_env = get_irg_link(callee);
2103                 irg_inline_property prop        = get_irg_inline_property(callee);
2104                 int                 loop_depth;
2105                 const call_entry    *centry;
2106                 pmap_entry          *e;
2107
2108                 if ((prop < irg_inline_forced) && env->n_nodes + callee_env->n_nodes > maxsize) {
2109                         DB((dbg, LEVEL_2, "%+F: too big (%d) + %+F (%d)\n", irg,
2110                                                 env->n_nodes, callee, callee_env->n_nodes));
2111                         continue;
2112                 }
2113
2114                 e = pmap_find(copied_graphs, callee);
2115                 if (e != NULL) {
2116                         int benefice = curr_call->benefice;
2117                         /*
2118                          * Reduce the weight for recursive function IFF not all arguments are const.
2119                          * inlining recursive functions is rarely good.
2120                          */
2121                         if (!curr_call->all_const)
2122                                 benefice -= 2000;
2123                         if (benefice < inline_threshold)
2124                                 continue;
2125
2126                         /*
2127                          * Remap callee if we have a copy.
2128                          */
2129                         callee     = e->value;
2130                         callee_env = get_irg_link(callee);
2131                 }
2132
2133                 if (current_ir_graph == callee) {
2134                         /*
2135                          * Recursive call: we cannot directly inline because we cannot
2136                          * walk the graph and change it. So we have to make a copy of
2137                          * the graph first.
2138                          */
2139                         int benefice = curr_call->benefice;
2140                         ir_graph *copy;
2141
2142                         /*
2143                          * Reduce the weight for recursive function IFF not all arguments are const.
2144                          * inlining recursive functions is rarely good.
2145                          */
2146                         if (!curr_call->all_const)
2147                                 benefice -= 2000;
2148                         if (benefice < inline_threshold)
2149                                 continue;
2150
2151                         ir_free_resources(irg, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
2152
2153                         /*
2154                          * No copy yet, create one.
2155                          * Note that recursive methods are never leaves, so it is
2156                          * sufficient to test this condition here.
2157                          */
2158                         copy = create_irg_copy(callee);
2159
2160                         /* create_irg_copy() destroys the Proj links, recompute them */
2161                         phiproj_computed = 0;
2162
2163                         ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
2164
2165                         /* allocate a new environment */
2166                         callee_env = alloc_inline_irg_env();
2167                         set_irg_link(copy, callee_env);
2168
2169                         assure_cf_loop(copy);
2170                         wenv.x              = callee_env;
2171                         wenv.ignore_callers = 1;
2172                         irg_walk_graph(copy, NULL, collect_calls2, &wenv);
2173
2174                         /*
2175                          * Enter the entity of the original graph. This is needed
2176                          * for inline_method(). However, note that ent->irg still points
2177                          * to callee, NOT to copy.
2178                          */
2179                         set_irg_entity(copy, get_irg_entity(callee));
2180
2181                         pmap_insert(copied_graphs, callee, copy);
2182                         callee = copy;
2183
2184                         /* we have only one caller: the original graph */
2185                         callee_env->n_callers      = 1;
2186                         callee_env->n_callers_orig = 1;
2187                 }
2188                 if (! phiproj_computed) {
2189                         phiproj_computed = 1;
2190                         collect_phiprojs(current_ir_graph);
2191                 }
2192                 did_inline = inline_method(call_node, callee);
2193                 if (!did_inline)
2194                         continue;
2195
2196                 /* call was inlined, Phi/Projs for current graph must be recomputed */
2197                 phiproj_computed = 0;
2198
2199                 /* remove it from the caller list */
2200                 list_del(&curr_call->list);
2201
2202                 /* callee was inline. Append it's call list. */
2203                 env->got_inline = 1;
2204                 if (curr_call->local_adr)
2205                         env->local_vars = 1;
2206                 --env->n_call_nodes;
2207
2208                 /* we just generate a bunch of new calls */
2209                 loop_depth = curr_call->loop_depth;
2210                 list_for_each_entry(call_entry, centry, &callee_env->calls, list) {
2211                         inline_irg_env *penv = get_irg_link(centry->callee);
2212                         ir_node        *new_call;
2213                         call_entry     *new_entry;
2214
2215                         /* after we have inlined callee, all called methods inside
2216                          * callee are now called once more */
2217                         ++penv->n_callers;
2218
2219                         /* Note that the src list points to Call nodes in the inlined graph,
2220                          * but we need Call nodes in our graph. Luckily the inliner leaves
2221                          * this information in the link field. */
2222                         new_call = get_irn_link(centry->call);
2223                         assert(is_Call(new_call));
2224
2225                         new_entry = duplicate_call_entry(centry, new_call, loop_depth);
2226                         list_add_tail(&new_entry->list, &env->calls);
2227                         maybe_push_call(pqueue, new_entry, inline_threshold);
2228                 }
2229
2230                 env->n_call_nodes += callee_env->n_call_nodes;
2231                 env->n_nodes += callee_env->n_nodes;
2232                 --callee_env->n_callers;
2233         }
2234         ir_free_resources(irg, IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST);
2235         del_pqueue(pqueue);
2236 }
2237
2238 /*
2239  * Heuristic inliner. Calculates a benefice value for every call and inlines
2240  * those calls with a value higher than the threshold.
2241  */
2242 void inline_functions(unsigned maxsize, int inline_threshold) {
2243         inline_irg_env   *env;
2244         int              i, n_irgs;
2245         ir_graph         *rem;
2246         wenv_t           wenv;
2247         pmap             *copied_graphs;
2248         pmap_entry       *pm_entry;
2249         ir_graph         **irgs;
2250
2251         rem = current_ir_graph;
2252         obstack_init(&temp_obst);
2253
2254         irgs = create_irg_list();
2255
2256         /* a map for the copied graphs, used to inline recursive calls */
2257         copied_graphs = pmap_create();
2258
2259         /* extend all irgs by a temporary data structure for inlining. */
2260         n_irgs = get_irp_n_irgs();
2261         for (i = 0; i < n_irgs; ++i)
2262                 set_irg_link(irgs[i], alloc_inline_irg_env());
2263
2264         /* Pre-compute information in temporary data structure. */
2265         wenv.ignore_runtime = 0;
2266         wenv.ignore_callers = 0;
2267         for (i = 0; i < n_irgs; ++i) {
2268                 ir_graph *irg = irgs[i];
2269
2270                 free_callee_info(irg);
2271
2272                 wenv.x = get_irg_link(irg);
2273                 assure_cf_loop(irg);
2274                 irg_walk_graph(irg, NULL, collect_calls2, &wenv);
2275         }
2276
2277         /* -- and now inline. -- */
2278         for (i = 0; i < n_irgs; ++i) {
2279                 ir_graph *irg = irgs[i];
2280
2281                 inline_into(irg, maxsize, inline_threshold, copied_graphs);
2282         }
2283
2284         for (i = 0; i < n_irgs; ++i) {
2285                 ir_graph *irg = irgs[i];
2286
2287                 env = get_irg_link(irg);
2288                 if (env->got_inline) {
2289                         /* this irg got calls inlined: optimize it */
2290                         if (get_opt_combo()) {
2291                                 if (env->local_vars) {
2292                                         scalar_replacement_opt(irg);
2293                                 }
2294                                 combo(irg);
2295                         } else {
2296                                 if (env->local_vars) {
2297                                         if (scalar_replacement_opt(irg)) {
2298                                                 optimize_graph_df(irg);
2299                                         }
2300                                 }
2301                                 optimize_cf(irg);
2302                         }
2303                 }
2304                 if (env->got_inline || (env->n_callers_orig != env->n_callers)) {
2305                         DB((dbg, LEVEL_1, "Nodes:%3d ->%3d, calls:%3d ->%3d, callers:%3d ->%3d, -- %s\n",
2306                         env->n_nodes_orig, env->n_nodes, env->n_call_nodes_orig, env->n_call_nodes,
2307                         env->n_callers_orig, env->n_callers,
2308                         get_entity_name(get_irg_entity(irg))));
2309                 }
2310         }
2311
2312         /* kill the copied graphs: we don't need them anymore */
2313         foreach_pmap(copied_graphs, pm_entry) {
2314                 ir_graph *copy = pm_entry->value;
2315
2316                 /* reset the entity, otherwise it will be deleted in the next step ... */
2317                 set_irg_entity(copy, NULL);
2318                 free_ir_graph(copy);
2319         }
2320         pmap_destroy(copied_graphs);
2321
2322         xfree(irgs);
2323
2324         obstack_free(&temp_obst, NULL);
2325         current_ir_graph = rem;
2326 }
2327
2328 void firm_init_inline(void) {
2329         FIRM_DBG_REGISTER(dbg, "firm.opt.inline");
2330 }