comparison src/share/vm/opto/superword.cpp @ 0:a61af66fc99e jdk7-b24

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author duke
date Sat, 01 Dec 2007 00:00:00 +0000
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1 /*
2 * Copyright 2007 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 */
23
24 #include "incls/_precompiled.incl"
25 #include "incls/_superword.cpp.incl"
26
27 //
28 // S U P E R W O R D T R A N S F O R M
29 //=============================================================================
30
31 //------------------------------SuperWord---------------------------
32 SuperWord::SuperWord(PhaseIdealLoop* phase) :
33 _phase(phase),
34 _igvn(phase->_igvn),
35 _arena(phase->C->comp_arena()),
36 _packset(arena(), 8, 0, NULL), // packs for the current block
37 _bb_idx(arena(), (int)(1.10 * phase->C->unique()), 0, 0), // node idx to index in bb
38 _block(arena(), 8, 0, NULL), // nodes in current block
39 _data_entry(arena(), 8, 0, NULL), // nodes with all inputs from outside
40 _mem_slice_head(arena(), 8, 0, NULL), // memory slice heads
41 _mem_slice_tail(arena(), 8, 0, NULL), // memory slice tails
42 _node_info(arena(), 8, 0, SWNodeInfo::initial), // info needed per node
43 _align_to_ref(NULL), // memory reference to align vectors to
44 _disjoint_ptrs(arena(), 8, 0, OrderedPair::initial), // runtime disambiguated pointer pairs
45 _dg(_arena), // dependence graph
46 _visited(arena()), // visited node set
47 _post_visited(arena()), // post visited node set
48 _n_idx_list(arena(), 8), // scratch list of (node,index) pairs
49 _stk(arena(), 8, 0, NULL), // scratch stack of nodes
50 _nlist(arena(), 8, 0, NULL), // scratch list of nodes
51 _lpt(NULL), // loop tree node
52 _lp(NULL), // LoopNode
53 _bb(NULL), // basic block
54 _iv(NULL) // induction var
55 {}
56
57 //------------------------------transform_loop---------------------------
58 void SuperWord::transform_loop(IdealLoopTree* lpt) {
59 assert(lpt->_head->is_CountedLoop(), "must be");
60 CountedLoopNode *cl = lpt->_head->as_CountedLoop();
61
62 if (!cl->is_main_loop() ) return; // skip normal, pre, and post loops
63
64 // Check for no control flow in body (other than exit)
65 Node *cl_exit = cl->loopexit();
66 if (cl_exit->in(0) != lpt->_head) return;
67
68 // Check for pre-loop ending with CountedLoopEnd(Bool(Cmp(x,Opaque1(limit))))
69 CountedLoopEndNode* pre_end = get_pre_loop_end(cl);
70 if (pre_end == NULL) return;
71 Node *pre_opaq1 = pre_end->limit();
72 if (pre_opaq1->Opcode() != Op_Opaque1) return;
73
74 // Do vectors exist on this architecture?
75 if (vector_width_in_bytes() == 0) return;
76
77 init(); // initialize data structures
78
79 set_lpt(lpt);
80 set_lp(cl);
81
82 // For now, define one block which is the entire loop body
83 set_bb(cl);
84
85 assert(_packset.length() == 0, "packset must be empty");
86 SLP_extract();
87 }
88
89 //------------------------------SLP_extract---------------------------
90 // Extract the superword level parallelism
91 //
92 // 1) A reverse post-order of nodes in the block is constructed. By scanning
93 // this list from first to last, all definitions are visited before their uses.
94 //
95 // 2) A point-to-point dependence graph is constructed between memory references.
96 // This simplies the upcoming "independence" checker.
97 //
98 // 3) The maximum depth in the node graph from the beginning of the block
99 // to each node is computed. This is used to prune the graph search
100 // in the independence checker.
101 //
102 // 4) For integer types, the necessary bit width is propagated backwards
103 // from stores to allow packed operations on byte, char, and short
104 // integers. This reverses the promotion to type "int" that javac
105 // did for operations like: char c1,c2,c3; c1 = c2 + c3.
106 //
107 // 5) One of the memory references is picked to be an aligned vector reference.
108 // The pre-loop trip count is adjusted to align this reference in the
109 // unrolled body.
110 //
111 // 6) The initial set of pack pairs is seeded with memory references.
112 //
113 // 7) The set of pack pairs is extended by following use->def and def->use links.
114 //
115 // 8) The pairs are combined into vector sized packs.
116 //
117 // 9) Reorder the memory slices to co-locate members of the memory packs.
118 //
119 // 10) Generate ideal vector nodes for the final set of packs and where necessary,
120 // inserting scalar promotion, vector creation from multiple scalars, and
121 // extraction of scalar values from vectors.
122 //
123 void SuperWord::SLP_extract() {
124
125 // Ready the block
126
127 construct_bb();
128
129 dependence_graph();
130
131 compute_max_depth();
132
133 compute_vector_element_type();
134
135 // Attempt vectorization
136
137 find_adjacent_refs();
138
139 extend_packlist();
140
141 combine_packs();
142
143 construct_my_pack_map();
144
145 filter_packs();
146
147 schedule();
148
149 output();
150 }
151
152 //------------------------------find_adjacent_refs---------------------------
153 // Find the adjacent memory references and create pack pairs for them.
154 // This is the initial set of packs that will then be extended by
155 // following use->def and def->use links. The align positions are
156 // assigned relative to the reference "align_to_ref"
157 void SuperWord::find_adjacent_refs() {
158 // Get list of memory operations
159 Node_List memops;
160 for (int i = 0; i < _block.length(); i++) {
161 Node* n = _block.at(i);
162 if (n->is_Mem() && in_bb(n)) {
163 int align = memory_alignment(n->as_Mem(), 0);
164 if (align != bottom_align) {
165 memops.push(n);
166 }
167 }
168 }
169 if (memops.size() == 0) return;
170
171 // Find a memory reference to align to. The pre-loop trip count
172 // is modified to align this reference to a vector-aligned address
173 find_align_to_ref(memops);
174 if (align_to_ref() == NULL) return;
175
176 SWPointer align_to_ref_p(align_to_ref(), this);
177 int offset = align_to_ref_p.offset_in_bytes();
178 int scale = align_to_ref_p.scale_in_bytes();
179 int vw = vector_width_in_bytes();
180 int stride_sign = (scale * iv_stride()) > 0 ? 1 : -1;
181 int iv_adjustment = (stride_sign * vw - (offset % vw)) % vw;
182
183 #ifndef PRODUCT
184 if (TraceSuperWord)
185 tty->print_cr("\noffset = %d iv_adjustment = %d elt_align = %d",
186 offset, iv_adjustment, align_to_ref_p.memory_size());
187 #endif
188
189 // Set alignment relative to "align_to_ref"
190 for (int i = memops.size() - 1; i >= 0; i--) {
191 MemNode* s = memops.at(i)->as_Mem();
192 SWPointer p2(s, this);
193 if (p2.comparable(align_to_ref_p)) {
194 int align = memory_alignment(s, iv_adjustment);
195 set_alignment(s, align);
196 } else {
197 memops.remove(i);
198 }
199 }
200
201 // Create initial pack pairs of memory operations
202 for (uint i = 0; i < memops.size(); i++) {
203 Node* s1 = memops.at(i);
204 for (uint j = 0; j < memops.size(); j++) {
205 Node* s2 = memops.at(j);
206 if (s1 != s2 && are_adjacent_refs(s1, s2)) {
207 int align = alignment(s1);
208 if (stmts_can_pack(s1, s2, align)) {
209 Node_List* pair = new Node_List();
210 pair->push(s1);
211 pair->push(s2);
212 _packset.append(pair);
213 }
214 }
215 }
216 }
217
218 #ifndef PRODUCT
219 if (TraceSuperWord) {
220 tty->print_cr("\nAfter find_adjacent_refs");
221 print_packset();
222 }
223 #endif
224 }
225
226 //------------------------------find_align_to_ref---------------------------
227 // Find a memory reference to align the loop induction variable to.
228 // Looks first at stores then at loads, looking for a memory reference
229 // with the largest number of references similar to it.
230 void SuperWord::find_align_to_ref(Node_List &memops) {
231 GrowableArray<int> cmp_ct(arena(), memops.size(), memops.size(), 0);
232
233 // Count number of comparable memory ops
234 for (uint i = 0; i < memops.size(); i++) {
235 MemNode* s1 = memops.at(i)->as_Mem();
236 SWPointer p1(s1, this);
237 // Discard if pre loop can't align this reference
238 if (!ref_is_alignable(p1)) {
239 *cmp_ct.adr_at(i) = 0;
240 continue;
241 }
242 for (uint j = i+1; j < memops.size(); j++) {
243 MemNode* s2 = memops.at(j)->as_Mem();
244 if (isomorphic(s1, s2)) {
245 SWPointer p2(s2, this);
246 if (p1.comparable(p2)) {
247 (*cmp_ct.adr_at(i))++;
248 (*cmp_ct.adr_at(j))++;
249 }
250 }
251 }
252 }
253
254 // Find Store (or Load) with the greatest number of "comparable" references
255 int max_ct = 0;
256 int max_idx = -1;
257 int min_size = max_jint;
258 int min_iv_offset = max_jint;
259 for (uint j = 0; j < memops.size(); j++) {
260 MemNode* s = memops.at(j)->as_Mem();
261 if (s->is_Store()) {
262 SWPointer p(s, this);
263 if (cmp_ct.at(j) > max_ct ||
264 cmp_ct.at(j) == max_ct && (data_size(s) < min_size ||
265 data_size(s) == min_size &&
266 p.offset_in_bytes() < min_iv_offset)) {
267 max_ct = cmp_ct.at(j);
268 max_idx = j;
269 min_size = data_size(s);
270 min_iv_offset = p.offset_in_bytes();
271 }
272 }
273 }
274 // If no stores, look at loads
275 if (max_ct == 0) {
276 for (uint j = 0; j < memops.size(); j++) {
277 MemNode* s = memops.at(j)->as_Mem();
278 if (s->is_Load()) {
279 SWPointer p(s, this);
280 if (cmp_ct.at(j) > max_ct ||
281 cmp_ct.at(j) == max_ct && (data_size(s) < min_size ||
282 data_size(s) == min_size &&
283 p.offset_in_bytes() < min_iv_offset)) {
284 max_ct = cmp_ct.at(j);
285 max_idx = j;
286 min_size = data_size(s);
287 min_iv_offset = p.offset_in_bytes();
288 }
289 }
290 }
291 }
292
293 if (max_ct > 0)
294 set_align_to_ref(memops.at(max_idx)->as_Mem());
295
296 #ifndef PRODUCT
297 if (TraceSuperWord && Verbose) {
298 tty->print_cr("\nVector memops after find_align_to_refs");
299 for (uint i = 0; i < memops.size(); i++) {
300 MemNode* s = memops.at(i)->as_Mem();
301 s->dump();
302 }
303 }
304 #endif
305 }
306
307 //------------------------------ref_is_alignable---------------------------
308 // Can the preloop align the reference to position zero in the vector?
309 bool SuperWord::ref_is_alignable(SWPointer& p) {
310 if (!p.has_iv()) {
311 return true; // no induction variable
312 }
313 CountedLoopEndNode* pre_end = get_pre_loop_end(lp()->as_CountedLoop());
314 assert(pre_end->stride_is_con(), "pre loop stride is constant");
315 int preloop_stride = pre_end->stride_con();
316
317 int span = preloop_stride * p.scale_in_bytes();
318
319 // Stride one accesses are alignable.
320 if (ABS(span) == p.memory_size())
321 return true;
322
323 // If initial offset from start of object is computable,
324 // compute alignment within the vector.
325 int vw = vector_width_in_bytes();
326 if (vw % span == 0) {
327 Node* init_nd = pre_end->init_trip();
328 if (init_nd->is_Con() && p.invar() == NULL) {
329 int init = init_nd->bottom_type()->is_int()->get_con();
330
331 int init_offset = init * p.scale_in_bytes() + p.offset_in_bytes();
332 assert(init_offset >= 0, "positive offset from object start");
333
334 if (span > 0) {
335 return (vw - (init_offset % vw)) % span == 0;
336 } else {
337 assert(span < 0, "nonzero stride * scale");
338 return (init_offset % vw) % -span == 0;
339 }
340 }
341 }
342 return false;
343 }
344
345 //---------------------------dependence_graph---------------------------
346 // Construct dependency graph.
347 // Add dependence edges to load/store nodes for memory dependence
348 // A.out()->DependNode.in(1) and DependNode.out()->B.prec(x)
349 void SuperWord::dependence_graph() {
350 // First, assign a dependence node to each memory node
351 for (int i = 0; i < _block.length(); i++ ) {
352 Node *n = _block.at(i);
353 if (n->is_Mem() || n->is_Phi() && n->bottom_type() == Type::MEMORY) {
354 _dg.make_node(n);
355 }
356 }
357
358 // For each memory slice, create the dependences
359 for (int i = 0; i < _mem_slice_head.length(); i++) {
360 Node* n = _mem_slice_head.at(i);
361 Node* n_tail = _mem_slice_tail.at(i);
362
363 // Get slice in predecessor order (last is first)
364 mem_slice_preds(n_tail, n, _nlist);
365
366 // Make the slice dependent on the root
367 DepMem* slice = _dg.dep(n);
368 _dg.make_edge(_dg.root(), slice);
369
370 // Create a sink for the slice
371 DepMem* slice_sink = _dg.make_node(NULL);
372 _dg.make_edge(slice_sink, _dg.tail());
373
374 // Now visit each pair of memory ops, creating the edges
375 for (int j = _nlist.length() - 1; j >= 0 ; j--) {
376 Node* s1 = _nlist.at(j);
377
378 // If no dependency yet, use slice
379 if (_dg.dep(s1)->in_cnt() == 0) {
380 _dg.make_edge(slice, s1);
381 }
382 SWPointer p1(s1->as_Mem(), this);
383 bool sink_dependent = true;
384 for (int k = j - 1; k >= 0; k--) {
385 Node* s2 = _nlist.at(k);
386 if (s1->is_Load() && s2->is_Load())
387 continue;
388 SWPointer p2(s2->as_Mem(), this);
389
390 int cmp = p1.cmp(p2);
391 if (SuperWordRTDepCheck &&
392 p1.base() != p2.base() && p1.valid() && p2.valid()) {
393 // Create a runtime check to disambiguate
394 OrderedPair pp(p1.base(), p2.base());
395 _disjoint_ptrs.append_if_missing(pp);
396 } else if (!SWPointer::not_equal(cmp)) {
397 // Possibly same address
398 _dg.make_edge(s1, s2);
399 sink_dependent = false;
400 }
401 }
402 if (sink_dependent) {
403 _dg.make_edge(s1, slice_sink);
404 }
405 }
406 #ifndef PRODUCT
407 if (TraceSuperWord) {
408 tty->print_cr("\nDependence graph for slice: %d", n->_idx);
409 for (int q = 0; q < _nlist.length(); q++) {
410 _dg.print(_nlist.at(q));
411 }
412 tty->cr();
413 }
414 #endif
415 _nlist.clear();
416 }
417
418 #ifndef PRODUCT
419 if (TraceSuperWord) {
420 tty->print_cr("\ndisjoint_ptrs: %s", _disjoint_ptrs.length() > 0 ? "" : "NONE");
421 for (int r = 0; r < _disjoint_ptrs.length(); r++) {
422 _disjoint_ptrs.at(r).print();
423 tty->cr();
424 }
425 tty->cr();
426 }
427 #endif
428 }
429
430 //---------------------------mem_slice_preds---------------------------
431 // Return a memory slice (node list) in predecessor order starting at "start"
432 void SuperWord::mem_slice_preds(Node* start, Node* stop, GrowableArray<Node*> &preds) {
433 assert(preds.length() == 0, "start empty");
434 Node* n = start;
435 Node* prev = NULL;
436 while (true) {
437 assert(in_bb(n), "must be in block");
438 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
439 Node* out = n->fast_out(i);
440 if (out->is_Load()) {
441 if (in_bb(out)) {
442 preds.push(out);
443 }
444 } else {
445 // FIXME
446 if (out->is_MergeMem() && !in_bb(out)) {
447 // Either unrolling is causing a memory edge not to disappear,
448 // or need to run igvn.optimize() again before SLP
449 } else if (out->is_Phi() && out->bottom_type() == Type::MEMORY && !in_bb(out)) {
450 // Ditto. Not sure what else to check further.
451 } else if (out->Opcode() == Op_StoreCM && out->in(4) == n) {
452 // StoreCM has an input edge used as a precedence edge.
453 // Maybe an issue when oop stores are vectorized.
454 } else {
455 assert(out == prev || prev == NULL, "no branches off of store slice");
456 }
457 }
458 }
459 if (n == stop) break;
460 preds.push(n);
461 prev = n;
462 n = n->in(MemNode::Memory);
463 }
464 }
465
466 //------------------------------stmts_can_pack---------------------------
467 // Can s1 and s2 be in a pack with s1 immediately preceeding s2 and
468 // s1 aligned at "align"
469 bool SuperWord::stmts_can_pack(Node* s1, Node* s2, int align) {
470 if (isomorphic(s1, s2)) {
471 if (independent(s1, s2)) {
472 if (!exists_at(s1, 0) && !exists_at(s2, 1)) {
473 if (!s1->is_Mem() || are_adjacent_refs(s1, s2)) {
474 int s1_align = alignment(s1);
475 int s2_align = alignment(s2);
476 if (s1_align == top_align || s1_align == align) {
477 if (s2_align == top_align || s2_align == align + data_size(s1)) {
478 return true;
479 }
480 }
481 }
482 }
483 }
484 }
485 return false;
486 }
487
488 //------------------------------exists_at---------------------------
489 // Does s exist in a pack at position pos?
490 bool SuperWord::exists_at(Node* s, uint pos) {
491 for (int i = 0; i < _packset.length(); i++) {
492 Node_List* p = _packset.at(i);
493 if (p->at(pos) == s) {
494 return true;
495 }
496 }
497 return false;
498 }
499
500 //------------------------------are_adjacent_refs---------------------------
501 // Is s1 immediately before s2 in memory?
502 bool SuperWord::are_adjacent_refs(Node* s1, Node* s2) {
503 if (!s1->is_Mem() || !s2->is_Mem()) return false;
504 if (!in_bb(s1) || !in_bb(s2)) return false;
505 // FIXME - co_locate_pack fails on Stores in different mem-slices, so
506 // only pack memops that are in the same alias set until that's fixed.
507 if (_phase->C->get_alias_index(s1->as_Mem()->adr_type()) !=
508 _phase->C->get_alias_index(s2->as_Mem()->adr_type()))
509 return false;
510 SWPointer p1(s1->as_Mem(), this);
511 SWPointer p2(s2->as_Mem(), this);
512 if (p1.base() != p2.base() || !p1.comparable(p2)) return false;
513 int diff = p2.offset_in_bytes() - p1.offset_in_bytes();
514 return diff == data_size(s1);
515 }
516
517 //------------------------------isomorphic---------------------------
518 // Are s1 and s2 similar?
519 bool SuperWord::isomorphic(Node* s1, Node* s2) {
520 if (s1->Opcode() != s2->Opcode()) return false;
521 if (s1->req() != s2->req()) return false;
522 if (s1->in(0) != s2->in(0)) return false;
523 if (velt_type(s1) != velt_type(s2)) return false;
524 return true;
525 }
526
527 //------------------------------independent---------------------------
528 // Is there no data path from s1 to s2 or s2 to s1?
529 bool SuperWord::independent(Node* s1, Node* s2) {
530 // assert(s1->Opcode() == s2->Opcode(), "check isomorphic first");
531 int d1 = depth(s1);
532 int d2 = depth(s2);
533 if (d1 == d2) return s1 != s2;
534 Node* deep = d1 > d2 ? s1 : s2;
535 Node* shallow = d1 > d2 ? s2 : s1;
536
537 visited_clear();
538
539 return independent_path(shallow, deep);
540 }
541
542 //------------------------------independent_path------------------------------
543 // Helper for independent
544 bool SuperWord::independent_path(Node* shallow, Node* deep, uint dp) {
545 if (dp >= 1000) return false; // stop deep recursion
546 visited_set(deep);
547 int shal_depth = depth(shallow);
548 assert(shal_depth <= depth(deep), "must be");
549 for (DepPreds preds(deep, _dg); !preds.done(); preds.next()) {
550 Node* pred = preds.current();
551 if (in_bb(pred) && !visited_test(pred)) {
552 if (shallow == pred) {
553 return false;
554 }
555 if (shal_depth < depth(pred) && !independent_path(shallow, pred, dp+1)) {
556 return false;
557 }
558 }
559 }
560 return true;
561 }
562
563 //------------------------------set_alignment---------------------------
564 void SuperWord::set_alignment(Node* s1, Node* s2, int align) {
565 set_alignment(s1, align);
566 set_alignment(s2, align + data_size(s1));
567 }
568
569 //------------------------------data_size---------------------------
570 int SuperWord::data_size(Node* s) {
571 const Type* t = velt_type(s);
572 BasicType bt = t->array_element_basic_type();
573 int bsize = type2aelembytes[bt];
574 assert(bsize != 0, "valid size");
575 return bsize;
576 }
577
578 //------------------------------extend_packlist---------------------------
579 // Extend packset by following use->def and def->use links from pack members.
580 void SuperWord::extend_packlist() {
581 bool changed;
582 do {
583 changed = false;
584 for (int i = 0; i < _packset.length(); i++) {
585 Node_List* p = _packset.at(i);
586 changed |= follow_use_defs(p);
587 changed |= follow_def_uses(p);
588 }
589 } while (changed);
590
591 #ifndef PRODUCT
592 if (TraceSuperWord) {
593 tty->print_cr("\nAfter extend_packlist");
594 print_packset();
595 }
596 #endif
597 }
598
599 //------------------------------follow_use_defs---------------------------
600 // Extend the packset by visiting operand definitions of nodes in pack p
601 bool SuperWord::follow_use_defs(Node_List* p) {
602 Node* s1 = p->at(0);
603 Node* s2 = p->at(1);
604 assert(p->size() == 2, "just checking");
605 assert(s1->req() == s2->req(), "just checking");
606 assert(alignment(s1) + data_size(s1) == alignment(s2), "just checking");
607
608 if (s1->is_Load()) return false;
609
610 int align = alignment(s1);
611 bool changed = false;
612 int start = s1->is_Store() ? MemNode::ValueIn : 1;
613 int end = s1->is_Store() ? MemNode::ValueIn+1 : s1->req();
614 for (int j = start; j < end; j++) {
615 Node* t1 = s1->in(j);
616 Node* t2 = s2->in(j);
617 if (!in_bb(t1) || !in_bb(t2))
618 continue;
619 if (stmts_can_pack(t1, t2, align)) {
620 if (est_savings(t1, t2) >= 0) {
621 Node_List* pair = new Node_List();
622 pair->push(t1);
623 pair->push(t2);
624 _packset.append(pair);
625 set_alignment(t1, t2, align);
626 changed = true;
627 }
628 }
629 }
630 return changed;
631 }
632
633 //------------------------------follow_def_uses---------------------------
634 // Extend the packset by visiting uses of nodes in pack p
635 bool SuperWord::follow_def_uses(Node_List* p) {
636 bool changed = false;
637 Node* s1 = p->at(0);
638 Node* s2 = p->at(1);
639 assert(p->size() == 2, "just checking");
640 assert(s1->req() == s2->req(), "just checking");
641 assert(alignment(s1) + data_size(s1) == alignment(s2), "just checking");
642
643 if (s1->is_Store()) return false;
644
645 int align = alignment(s1);
646 int savings = -1;
647 Node* u1 = NULL;
648 Node* u2 = NULL;
649 for (DUIterator_Fast imax, i = s1->fast_outs(imax); i < imax; i++) {
650 Node* t1 = s1->fast_out(i);
651 if (!in_bb(t1)) continue;
652 for (DUIterator_Fast jmax, j = s2->fast_outs(jmax); j < jmax; j++) {
653 Node* t2 = s2->fast_out(j);
654 if (!in_bb(t2)) continue;
655 if (!opnd_positions_match(s1, t1, s2, t2))
656 continue;
657 if (stmts_can_pack(t1, t2, align)) {
658 int my_savings = est_savings(t1, t2);
659 if (my_savings > savings) {
660 savings = my_savings;
661 u1 = t1;
662 u2 = t2;
663 }
664 }
665 }
666 }
667 if (savings >= 0) {
668 Node_List* pair = new Node_List();
669 pair->push(u1);
670 pair->push(u2);
671 _packset.append(pair);
672 set_alignment(u1, u2, align);
673 changed = true;
674 }
675 return changed;
676 }
677
678 //---------------------------opnd_positions_match-------------------------
679 // Is the use of d1 in u1 at the same operand position as d2 in u2?
680 bool SuperWord::opnd_positions_match(Node* d1, Node* u1, Node* d2, Node* u2) {
681 uint ct = u1->req();
682 if (ct != u2->req()) return false;
683 uint i1 = 0;
684 uint i2 = 0;
685 do {
686 for (i1++; i1 < ct; i1++) if (u1->in(i1) == d1) break;
687 for (i2++; i2 < ct; i2++) if (u2->in(i2) == d2) break;
688 if (i1 != i2) {
689 return false;
690 }
691 } while (i1 < ct);
692 return true;
693 }
694
695 //------------------------------est_savings---------------------------
696 // Estimate the savings from executing s1 and s2 as a pack
697 int SuperWord::est_savings(Node* s1, Node* s2) {
698 int save = 2 - 1; // 2 operations per instruction in packed form
699
700 // inputs
701 for (uint i = 1; i < s1->req(); i++) {
702 Node* x1 = s1->in(i);
703 Node* x2 = s2->in(i);
704 if (x1 != x2) {
705 if (are_adjacent_refs(x1, x2)) {
706 save += adjacent_profit(x1, x2);
707 } else if (!in_packset(x1, x2)) {
708 save -= pack_cost(2);
709 } else {
710 save += unpack_cost(2);
711 }
712 }
713 }
714
715 // uses of result
716 uint ct = 0;
717 for (DUIterator_Fast imax, i = s1->fast_outs(imax); i < imax; i++) {
718 Node* s1_use = s1->fast_out(i);
719 for (int j = 0; j < _packset.length(); j++) {
720 Node_List* p = _packset.at(j);
721 if (p->at(0) == s1_use) {
722 for (DUIterator_Fast kmax, k = s2->fast_outs(kmax); k < kmax; k++) {
723 Node* s2_use = s2->fast_out(k);
724 if (p->at(p->size()-1) == s2_use) {
725 ct++;
726 if (are_adjacent_refs(s1_use, s2_use)) {
727 save += adjacent_profit(s1_use, s2_use);
728 }
729 }
730 }
731 }
732 }
733 }
734
735 if (ct < s1->outcnt()) save += unpack_cost(1);
736 if (ct < s2->outcnt()) save += unpack_cost(1);
737
738 return save;
739 }
740
741 //------------------------------costs---------------------------
742 int SuperWord::adjacent_profit(Node* s1, Node* s2) { return 2; }
743 int SuperWord::pack_cost(int ct) { return ct; }
744 int SuperWord::unpack_cost(int ct) { return ct; }
745
746 //------------------------------combine_packs---------------------------
747 // Combine packs A and B with A.last == B.first into A.first..,A.last,B.second,..B.last
748 void SuperWord::combine_packs() {
749 bool changed;
750 do {
751 changed = false;
752 for (int i = 0; i < _packset.length(); i++) {
753 Node_List* p1 = _packset.at(i);
754 if (p1 == NULL) continue;
755 for (int j = 0; j < _packset.length(); j++) {
756 Node_List* p2 = _packset.at(j);
757 if (p2 == NULL) continue;
758 if (p1->at(p1->size()-1) == p2->at(0)) {
759 for (uint k = 1; k < p2->size(); k++) {
760 p1->push(p2->at(k));
761 }
762 _packset.at_put(j, NULL);
763 changed = true;
764 }
765 }
766 }
767 } while (changed);
768
769 for (int i = _packset.length() - 1; i >= 0; i--) {
770 Node_List* p1 = _packset.at(i);
771 if (p1 == NULL) {
772 _packset.remove_at(i);
773 }
774 }
775
776 #ifndef PRODUCT
777 if (TraceSuperWord) {
778 tty->print_cr("\nAfter combine_packs");
779 print_packset();
780 }
781 #endif
782 }
783
784 //-----------------------------construct_my_pack_map--------------------------
785 // Construct the map from nodes to packs. Only valid after the
786 // point where a node is only in one pack (after combine_packs).
787 void SuperWord::construct_my_pack_map() {
788 Node_List* rslt = NULL;
789 for (int i = 0; i < _packset.length(); i++) {
790 Node_List* p = _packset.at(i);
791 for (uint j = 0; j < p->size(); j++) {
792 Node* s = p->at(j);
793 assert(my_pack(s) == NULL, "only in one pack");
794 set_my_pack(s, p);
795 }
796 }
797 }
798
799 //------------------------------filter_packs---------------------------
800 // Remove packs that are not implemented or not profitable.
801 void SuperWord::filter_packs() {
802
803 // Remove packs that are not implemented
804 for (int i = _packset.length() - 1; i >= 0; i--) {
805 Node_List* pk = _packset.at(i);
806 bool impl = implemented(pk);
807 if (!impl) {
808 #ifndef PRODUCT
809 if (TraceSuperWord && Verbose) {
810 tty->print_cr("Unimplemented");
811 pk->at(0)->dump();
812 }
813 #endif
814 remove_pack_at(i);
815 }
816 }
817
818 // Remove packs that are not profitable
819 bool changed;
820 do {
821 changed = false;
822 for (int i = _packset.length() - 1; i >= 0; i--) {
823 Node_List* pk = _packset.at(i);
824 bool prof = profitable(pk);
825 if (!prof) {
826 #ifndef PRODUCT
827 if (TraceSuperWord && Verbose) {
828 tty->print_cr("Unprofitable");
829 pk->at(0)->dump();
830 }
831 #endif
832 remove_pack_at(i);
833 changed = true;
834 }
835 }
836 } while (changed);
837
838 #ifndef PRODUCT
839 if (TraceSuperWord) {
840 tty->print_cr("\nAfter filter_packs");
841 print_packset();
842 tty->cr();
843 }
844 #endif
845 }
846
847 //------------------------------implemented---------------------------
848 // Can code be generated for pack p?
849 bool SuperWord::implemented(Node_List* p) {
850 Node* p0 = p->at(0);
851 int vopc = VectorNode::opcode(p0->Opcode(), p->size(), velt_type(p0));
852 return vopc > 0 && Matcher::has_match_rule(vopc);
853 }
854
855 //------------------------------profitable---------------------------
856 // For pack p, are all operands and all uses (with in the block) vector?
857 bool SuperWord::profitable(Node_List* p) {
858 Node* p0 = p->at(0);
859 uint start, end;
860 vector_opd_range(p0, &start, &end);
861
862 // Return false if some input is not vector and inside block
863 for (uint i = start; i < end; i++) {
864 if (!is_vector_use(p0, i)) {
865 // For now, return false if not scalar promotion case (inputs are the same.)
866 // Later, implement PackNode and allow differring, non-vector inputs
867 // (maybe just the ones from outside the block.)
868 Node* p0_def = p0->in(i);
869 for (uint j = 1; j < p->size(); j++) {
870 Node* use = p->at(j);
871 Node* def = use->in(i);
872 if (p0_def != def)
873 return false;
874 }
875 }
876 }
877 if (!p0->is_Store()) {
878 // For now, return false if not all uses are vector.
879 // Later, implement ExtractNode and allow non-vector uses (maybe
880 // just the ones outside the block.)
881 for (uint i = 0; i < p->size(); i++) {
882 Node* def = p->at(i);
883 for (DUIterator_Fast jmax, j = def->fast_outs(jmax); j < jmax; j++) {
884 Node* use = def->fast_out(j);
885 for (uint k = 0; k < use->req(); k++) {
886 Node* n = use->in(k);
887 if (def == n) {
888 if (!is_vector_use(use, k)) {
889 return false;
890 }
891 }
892 }
893 }
894 }
895 }
896 return true;
897 }
898
899 //------------------------------schedule---------------------------
900 // Adjust the memory graph for the packed operations
901 void SuperWord::schedule() {
902
903 // Co-locate in the memory graph the members of each memory pack
904 for (int i = 0; i < _packset.length(); i++) {
905 co_locate_pack(_packset.at(i));
906 }
907 }
908
909 //------------------------------co_locate_pack---------------------------
910 // Within a pack, move stores down to the last executed store,
911 // and move loads up to the first executed load.
912 void SuperWord::co_locate_pack(Node_List* pk) {
913 if (pk->at(0)->is_Store()) {
914 // Push Stores down towards last executed pack member
915 MemNode* first = executed_first(pk)->as_Mem();
916 MemNode* last = executed_last(pk)->as_Mem();
917 MemNode* insert_pt = last;
918 MemNode* current = last->in(MemNode::Memory)->as_Mem();
919 while (true) {
920 assert(in_bb(current), "stay in block");
921 Node* my_mem = current->in(MemNode::Memory);
922 if (in_pack(current, pk)) {
923 // Forward users of my memory state to my input memory state
924 _igvn.hash_delete(current);
925 _igvn.hash_delete(my_mem);
926 for (DUIterator i = current->outs(); current->has_out(i); i++) {
927 Node* use = current->out(i);
928 if (use->is_Mem()) {
929 assert(use->in(MemNode::Memory) == current, "must be");
930 _igvn.hash_delete(use);
931 use->set_req(MemNode::Memory, my_mem);
932 _igvn._worklist.push(use);
933 --i; // deleted this edge; rescan position
934 }
935 }
936 // put current immediately before insert_pt
937 current->set_req(MemNode::Memory, insert_pt->in(MemNode::Memory));
938 _igvn.hash_delete(insert_pt);
939 insert_pt->set_req(MemNode::Memory, current);
940 _igvn._worklist.push(insert_pt);
941 _igvn._worklist.push(current);
942 insert_pt = current;
943 }
944 if (current == first) break;
945 current = my_mem->as_Mem();
946 }
947 } else if (pk->at(0)->is_Load()) {
948 // Pull Loads up towards first executed pack member
949 LoadNode* first = executed_first(pk)->as_Load();
950 Node* first_mem = first->in(MemNode::Memory);
951 _igvn.hash_delete(first_mem);
952 // Give each load same memory state as first
953 for (uint i = 0; i < pk->size(); i++) {
954 LoadNode* ld = pk->at(i)->as_Load();
955 _igvn.hash_delete(ld);
956 ld->set_req(MemNode::Memory, first_mem);
957 _igvn._worklist.push(ld);
958 }
959 }
960 }
961
962 //------------------------------output---------------------------
963 // Convert packs into vector node operations
964 void SuperWord::output() {
965 if (_packset.length() == 0) return;
966
967 // MUST ENSURE main loop's initial value is properly aligned:
968 // (iv_initial_value + min_iv_offset) % vector_width_in_bytes() == 0
969
970 align_initial_loop_index(align_to_ref());
971
972 // Insert extract (unpack) operations for scalar uses
973 for (int i = 0; i < _packset.length(); i++) {
974 insert_extracts(_packset.at(i));
975 }
976
977 for (int i = 0; i < _block.length(); i++) {
978 Node* n = _block.at(i);
979 Node_List* p = my_pack(n);
980 if (p && n == executed_last(p)) {
981 uint vlen = p->size();
982 Node* vn = NULL;
983 Node* low_adr = p->at(0);
984 Node* first = executed_first(p);
985 if (n->is_Load()) {
986 int opc = n->Opcode();
987 Node* ctl = n->in(MemNode::Control);
988 Node* mem = first->in(MemNode::Memory);
989 Node* adr = low_adr->in(MemNode::Address);
990 const TypePtr* atyp = n->adr_type();
991 vn = VectorLoadNode::make(_phase->C, opc, ctl, mem, adr, atyp, vlen);
992
993 } else if (n->is_Store()) {
994 // Promote value to be stored to vector
995 VectorNode* val = vector_opd(p, MemNode::ValueIn);
996
997 int opc = n->Opcode();
998 Node* ctl = n->in(MemNode::Control);
999 Node* mem = first->in(MemNode::Memory);
1000 Node* adr = low_adr->in(MemNode::Address);
1001 const TypePtr* atyp = n->adr_type();
1002 vn = VectorStoreNode::make(_phase->C, opc, ctl, mem, adr, atyp, val, vlen);
1003
1004 } else if (n->req() == 3) {
1005 // Promote operands to vector
1006 Node* in1 = vector_opd(p, 1);
1007 Node* in2 = vector_opd(p, 2);
1008 vn = VectorNode::make(_phase->C, n->Opcode(), in1, in2, vlen, velt_type(n));
1009
1010 } else {
1011 ShouldNotReachHere();
1012 }
1013
1014 _phase->_igvn.register_new_node_with_optimizer(vn);
1015 _phase->set_ctrl(vn, _phase->get_ctrl(p->at(0)));
1016 for (uint j = 0; j < p->size(); j++) {
1017 Node* pm = p->at(j);
1018 _igvn.hash_delete(pm);
1019 _igvn.subsume_node(pm, vn);
1020 }
1021 _igvn._worklist.push(vn);
1022 }
1023 }
1024 }
1025
1026 //------------------------------vector_opd---------------------------
1027 // Create a vector operand for the nodes in pack p for operand: in(opd_idx)
1028 VectorNode* SuperWord::vector_opd(Node_List* p, int opd_idx) {
1029 Node* p0 = p->at(0);
1030 uint vlen = p->size();
1031 Node* opd = p0->in(opd_idx);
1032
1033 bool same_opd = true;
1034 for (uint i = 1; i < vlen; i++) {
1035 Node* pi = p->at(i);
1036 Node* in = pi->in(opd_idx);
1037 if (opd != in) {
1038 same_opd = false;
1039 break;
1040 }
1041 }
1042
1043 if (same_opd) {
1044 if (opd->is_Vector()) {
1045 return (VectorNode*)opd; // input is matching vector
1046 }
1047 // Convert scalar input to vector. Use p0's type because it's container
1048 // maybe smaller than the operand's container.
1049 const Type* opd_t = velt_type(!in_bb(opd) ? p0 : opd);
1050 const Type* p0_t = velt_type(p0);
1051 if (p0_t->higher_equal(opd_t)) opd_t = p0_t;
1052 VectorNode* vn = VectorNode::scalar2vector(_phase->C, opd, vlen, opd_t);
1053
1054 _phase->_igvn.register_new_node_with_optimizer(vn);
1055 _phase->set_ctrl(vn, _phase->get_ctrl(opd));
1056 return vn;
1057 }
1058
1059 // Insert pack operation
1060 const Type* opd_t = velt_type(!in_bb(opd) ? p0 : opd);
1061 PackNode* pk = PackNode::make(_phase->C, opd, opd_t);
1062
1063 for (uint i = 1; i < vlen; i++) {
1064 Node* pi = p->at(i);
1065 Node* in = pi->in(opd_idx);
1066 assert(my_pack(in) == NULL, "Should already have been unpacked");
1067 assert(opd_t == velt_type(!in_bb(in) ? pi : in), "all same type");
1068 pk->add_opd(in);
1069 }
1070 _phase->_igvn.register_new_node_with_optimizer(pk);
1071 _phase->set_ctrl(pk, _phase->get_ctrl(opd));
1072 return pk;
1073 }
1074
1075 //------------------------------insert_extracts---------------------------
1076 // If a use of pack p is not a vector use, then replace the
1077 // use with an extract operation.
1078 void SuperWord::insert_extracts(Node_List* p) {
1079 if (p->at(0)->is_Store()) return;
1080 assert(_n_idx_list.is_empty(), "empty (node,index) list");
1081
1082 // Inspect each use of each pack member. For each use that is
1083 // not a vector use, replace the use with an extract operation.
1084
1085 for (uint i = 0; i < p->size(); i++) {
1086 Node* def = p->at(i);
1087 for (DUIterator_Fast jmax, j = def->fast_outs(jmax); j < jmax; j++) {
1088 Node* use = def->fast_out(j);
1089 for (uint k = 0; k < use->req(); k++) {
1090 Node* n = use->in(k);
1091 if (def == n) {
1092 if (!is_vector_use(use, k)) {
1093 _n_idx_list.push(use, k);
1094 }
1095 }
1096 }
1097 }
1098 }
1099
1100 while (_n_idx_list.is_nonempty()) {
1101 Node* use = _n_idx_list.node();
1102 int idx = _n_idx_list.index();
1103 _n_idx_list.pop();
1104 Node* def = use->in(idx);
1105
1106 // Insert extract operation
1107 _igvn.hash_delete(def);
1108 _igvn.hash_delete(use);
1109 int def_pos = alignment(def) / data_size(def);
1110 const Type* def_t = velt_type(def);
1111
1112 Node* ex = ExtractNode::make(_phase->C, def, def_pos, def_t);
1113 _phase->_igvn.register_new_node_with_optimizer(ex);
1114 _phase->set_ctrl(ex, _phase->get_ctrl(def));
1115 use->set_req(idx, ex);
1116 _igvn._worklist.push(def);
1117 _igvn._worklist.push(use);
1118
1119 bb_insert_after(ex, bb_idx(def));
1120 set_velt_type(ex, def_t);
1121 }
1122 }
1123
1124 //------------------------------is_vector_use---------------------------
1125 // Is use->in(u_idx) a vector use?
1126 bool SuperWord::is_vector_use(Node* use, int u_idx) {
1127 Node_List* u_pk = my_pack(use);
1128 if (u_pk == NULL) return false;
1129 Node* def = use->in(u_idx);
1130 Node_List* d_pk = my_pack(def);
1131 if (d_pk == NULL) {
1132 // check for scalar promotion
1133 Node* n = u_pk->at(0)->in(u_idx);
1134 for (uint i = 1; i < u_pk->size(); i++) {
1135 if (u_pk->at(i)->in(u_idx) != n) return false;
1136 }
1137 return true;
1138 }
1139 if (u_pk->size() != d_pk->size())
1140 return false;
1141 for (uint i = 0; i < u_pk->size(); i++) {
1142 Node* ui = u_pk->at(i);
1143 Node* di = d_pk->at(i);
1144 if (ui->in(u_idx) != di || alignment(ui) != alignment(di))
1145 return false;
1146 }
1147 return true;
1148 }
1149
1150 //------------------------------construct_bb---------------------------
1151 // Construct reverse postorder list of block members
1152 void SuperWord::construct_bb() {
1153 Node* entry = bb();
1154
1155 assert(_stk.length() == 0, "stk is empty");
1156 assert(_block.length() == 0, "block is empty");
1157 assert(_data_entry.length() == 0, "data_entry is empty");
1158 assert(_mem_slice_head.length() == 0, "mem_slice_head is empty");
1159 assert(_mem_slice_tail.length() == 0, "mem_slice_tail is empty");
1160
1161 // Find non-control nodes with no inputs from within block,
1162 // create a temporary map from node _idx to bb_idx for use
1163 // by the visited and post_visited sets,
1164 // and count number of nodes in block.
1165 int bb_ct = 0;
1166 for (uint i = 0; i < lpt()->_body.size(); i++ ) {
1167 Node *n = lpt()->_body.at(i);
1168 set_bb_idx(n, i); // Create a temporary map
1169 if (in_bb(n)) {
1170 bb_ct++;
1171 if (!n->is_CFG()) {
1172 bool found = false;
1173 for (uint j = 0; j < n->req(); j++) {
1174 Node* def = n->in(j);
1175 if (def && in_bb(def)) {
1176 found = true;
1177 break;
1178 }
1179 }
1180 if (!found) {
1181 assert(n != entry, "can't be entry");
1182 _data_entry.push(n);
1183 }
1184 }
1185 }
1186 }
1187
1188 // Find memory slices (head and tail)
1189 for (DUIterator_Fast imax, i = lp()->fast_outs(imax); i < imax; i++) {
1190 Node *n = lp()->fast_out(i);
1191 if (in_bb(n) && (n->is_Phi() && n->bottom_type() == Type::MEMORY)) {
1192 Node* n_tail = n->in(LoopNode::LoopBackControl);
1193 _mem_slice_head.push(n);
1194 _mem_slice_tail.push(n_tail);
1195 }
1196 }
1197
1198 // Create an RPO list of nodes in block
1199
1200 visited_clear();
1201 post_visited_clear();
1202
1203 // Push all non-control nodes with no inputs from within block, then control entry
1204 for (int j = 0; j < _data_entry.length(); j++) {
1205 Node* n = _data_entry.at(j);
1206 visited_set(n);
1207 _stk.push(n);
1208 }
1209 visited_set(entry);
1210 _stk.push(entry);
1211
1212 // Do a depth first walk over out edges
1213 int rpo_idx = bb_ct - 1;
1214 int size;
1215 while ((size = _stk.length()) > 0) {
1216 Node* n = _stk.top(); // Leave node on stack
1217 if (!visited_test_set(n)) {
1218 // forward arc in graph
1219 } else if (!post_visited_test(n)) {
1220 // cross or back arc
1221 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1222 Node *use = n->fast_out(i);
1223 if (in_bb(use) && !visited_test(use) &&
1224 // Don't go around backedge
1225 (!use->is_Phi() || n == entry)) {
1226 _stk.push(use);
1227 }
1228 }
1229 if (_stk.length() == size) {
1230 // There were no additional uses, post visit node now
1231 _stk.pop(); // Remove node from stack
1232 assert(rpo_idx >= 0, "");
1233 _block.at_put_grow(rpo_idx, n);
1234 rpo_idx--;
1235 post_visited_set(n);
1236 assert(rpo_idx >= 0 || _stk.is_empty(), "");
1237 }
1238 } else {
1239 _stk.pop(); // Remove post-visited node from stack
1240 }
1241 }
1242
1243 // Create real map of block indices for nodes
1244 for (int j = 0; j < _block.length(); j++) {
1245 Node* n = _block.at(j);
1246 set_bb_idx(n, j);
1247 }
1248
1249 initialize_bb(); // Ensure extra info is allocated.
1250
1251 #ifndef PRODUCT
1252 if (TraceSuperWord) {
1253 print_bb();
1254 tty->print_cr("\ndata entry nodes: %s", _data_entry.length() > 0 ? "" : "NONE");
1255 for (int m = 0; m < _data_entry.length(); m++) {
1256 tty->print("%3d ", m);
1257 _data_entry.at(m)->dump();
1258 }
1259 tty->print_cr("\nmemory slices: %s", _mem_slice_head.length() > 0 ? "" : "NONE");
1260 for (int m = 0; m < _mem_slice_head.length(); m++) {
1261 tty->print("%3d ", m); _mem_slice_head.at(m)->dump();
1262 tty->print(" "); _mem_slice_tail.at(m)->dump();
1263 }
1264 }
1265 #endif
1266 assert(rpo_idx == -1 && bb_ct == _block.length(), "all block members found");
1267 }
1268
1269 //------------------------------initialize_bb---------------------------
1270 // Initialize per node info
1271 void SuperWord::initialize_bb() {
1272 Node* last = _block.at(_block.length() - 1);
1273 grow_node_info(bb_idx(last));
1274 }
1275
1276 //------------------------------bb_insert_after---------------------------
1277 // Insert n into block after pos
1278 void SuperWord::bb_insert_after(Node* n, int pos) {
1279 int n_pos = pos + 1;
1280 // Make room
1281 for (int i = _block.length() - 1; i >= n_pos; i--) {
1282 _block.at_put_grow(i+1, _block.at(i));
1283 }
1284 for (int j = _node_info.length() - 1; j >= n_pos; j--) {
1285 _node_info.at_put_grow(j+1, _node_info.at(j));
1286 }
1287 // Set value
1288 _block.at_put_grow(n_pos, n);
1289 _node_info.at_put_grow(n_pos, SWNodeInfo::initial);
1290 // Adjust map from node->_idx to _block index
1291 for (int i = n_pos; i < _block.length(); i++) {
1292 set_bb_idx(_block.at(i), i);
1293 }
1294 }
1295
1296 //------------------------------compute_max_depth---------------------------
1297 // Compute max depth for expressions from beginning of block
1298 // Use to prune search paths during test for independence.
1299 void SuperWord::compute_max_depth() {
1300 int ct = 0;
1301 bool again;
1302 do {
1303 again = false;
1304 for (int i = 0; i < _block.length(); i++) {
1305 Node* n = _block.at(i);
1306 if (!n->is_Phi()) {
1307 int d_orig = depth(n);
1308 int d_in = 0;
1309 for (DepPreds preds(n, _dg); !preds.done(); preds.next()) {
1310 Node* pred = preds.current();
1311 if (in_bb(pred)) {
1312 d_in = MAX2(d_in, depth(pred));
1313 }
1314 }
1315 if (d_in + 1 != d_orig) {
1316 set_depth(n, d_in + 1);
1317 again = true;
1318 }
1319 }
1320 }
1321 ct++;
1322 } while (again);
1323 #ifndef PRODUCT
1324 if (TraceSuperWord && Verbose)
1325 tty->print_cr("compute_max_depth iterated: %d times", ct);
1326 #endif
1327 }
1328
1329 //-------------------------compute_vector_element_type-----------------------
1330 // Compute necessary vector element type for expressions
1331 // This propagates backwards a narrower integer type when the
1332 // upper bits of the value are not needed.
1333 // Example: char a,b,c; a = b + c;
1334 // Normally the type of the add is integer, but for packed character
1335 // operations the type of the add needs to be char.
1336 void SuperWord::compute_vector_element_type() {
1337 #ifndef PRODUCT
1338 if (TraceSuperWord && Verbose)
1339 tty->print_cr("\ncompute_velt_type:");
1340 #endif
1341
1342 // Initial type
1343 for (int i = 0; i < _block.length(); i++) {
1344 Node* n = _block.at(i);
1345 const Type* t = n->is_Mem() ? Type::get_const_basic_type(n->as_Mem()->memory_type())
1346 : _igvn.type(n);
1347 const Type* vt = container_type(t);
1348 set_velt_type(n, vt);
1349 }
1350
1351 // Propagate narrowed type backwards through operations
1352 // that don't depend on higher order bits
1353 for (int i = _block.length() - 1; i >= 0; i--) {
1354 Node* n = _block.at(i);
1355 // Only integer types need be examined
1356 if (n->bottom_type()->isa_int()) {
1357 uint start, end;
1358 vector_opd_range(n, &start, &end);
1359 const Type* vt = velt_type(n);
1360
1361 for (uint j = start; j < end; j++) {
1362 Node* in = n->in(j);
1363 // Don't propagate through a type conversion
1364 if (n->bottom_type() != in->bottom_type())
1365 continue;
1366 switch(in->Opcode()) {
1367 case Op_AddI: case Op_AddL:
1368 case Op_SubI: case Op_SubL:
1369 case Op_MulI: case Op_MulL:
1370 case Op_AndI: case Op_AndL:
1371 case Op_OrI: case Op_OrL:
1372 case Op_XorI: case Op_XorL:
1373 case Op_LShiftI: case Op_LShiftL:
1374 case Op_CMoveI: case Op_CMoveL:
1375 if (in_bb(in)) {
1376 bool same_type = true;
1377 for (DUIterator_Fast kmax, k = in->fast_outs(kmax); k < kmax; k++) {
1378 Node *use = in->fast_out(k);
1379 if (!in_bb(use) || velt_type(use) != vt) {
1380 same_type = false;
1381 break;
1382 }
1383 }
1384 if (same_type) {
1385 set_velt_type(in, vt);
1386 }
1387 }
1388 }
1389 }
1390 }
1391 }
1392 #ifndef PRODUCT
1393 if (TraceSuperWord && Verbose) {
1394 for (int i = 0; i < _block.length(); i++) {
1395 Node* n = _block.at(i);
1396 velt_type(n)->dump();
1397 tty->print("\t");
1398 n->dump();
1399 }
1400 }
1401 #endif
1402 }
1403
1404 //------------------------------memory_alignment---------------------------
1405 // Alignment within a vector memory reference
1406 int SuperWord::memory_alignment(MemNode* s, int iv_adjust_in_bytes) {
1407 SWPointer p(s, this);
1408 if (!p.valid()) {
1409 return bottom_align;
1410 }
1411 int offset = p.offset_in_bytes();
1412 offset += iv_adjust_in_bytes;
1413 int off_rem = offset % vector_width_in_bytes();
1414 int off_mod = off_rem >= 0 ? off_rem : off_rem + vector_width_in_bytes();
1415 return off_mod;
1416 }
1417
1418 //---------------------------container_type---------------------------
1419 // Smallest type containing range of values
1420 const Type* SuperWord::container_type(const Type* t) {
1421 if (t->isa_aryptr()) {
1422 t = t->is_aryptr()->elem();
1423 }
1424 if (t->basic_type() == T_INT) {
1425 if (t->higher_equal(TypeInt::BOOL)) return TypeInt::BOOL;
1426 if (t->higher_equal(TypeInt::BYTE)) return TypeInt::BYTE;
1427 if (t->higher_equal(TypeInt::CHAR)) return TypeInt::CHAR;
1428 if (t->higher_equal(TypeInt::SHORT)) return TypeInt::SHORT;
1429 return TypeInt::INT;
1430 }
1431 return t;
1432 }
1433
1434 //-------------------------vector_opd_range-----------------------
1435 // (Start, end] half-open range defining which operands are vector
1436 void SuperWord::vector_opd_range(Node* n, uint* start, uint* end) {
1437 switch (n->Opcode()) {
1438 case Op_LoadB: case Op_LoadC:
1439 case Op_LoadI: case Op_LoadL:
1440 case Op_LoadF: case Op_LoadD:
1441 case Op_LoadP:
1442 *start = 0;
1443 *end = 0;
1444 return;
1445 case Op_StoreB: case Op_StoreC:
1446 case Op_StoreI: case Op_StoreL:
1447 case Op_StoreF: case Op_StoreD:
1448 case Op_StoreP:
1449 *start = MemNode::ValueIn;
1450 *end = *start + 1;
1451 return;
1452 case Op_LShiftI: case Op_LShiftL:
1453 *start = 1;
1454 *end = 2;
1455 return;
1456 case Op_CMoveI: case Op_CMoveL: case Op_CMoveF: case Op_CMoveD:
1457 *start = 2;
1458 *end = n->req();
1459 return;
1460 }
1461 *start = 1;
1462 *end = n->req(); // default is all operands
1463 }
1464
1465 //------------------------------in_packset---------------------------
1466 // Are s1 and s2 in a pack pair and ordered as s1,s2?
1467 bool SuperWord::in_packset(Node* s1, Node* s2) {
1468 for (int i = 0; i < _packset.length(); i++) {
1469 Node_List* p = _packset.at(i);
1470 assert(p->size() == 2, "must be");
1471 if (p->at(0) == s1 && p->at(p->size()-1) == s2) {
1472 return true;
1473 }
1474 }
1475 return false;
1476 }
1477
1478 //------------------------------in_pack---------------------------
1479 // Is s in pack p?
1480 Node_List* SuperWord::in_pack(Node* s, Node_List* p) {
1481 for (uint i = 0; i < p->size(); i++) {
1482 if (p->at(i) == s) {
1483 return p;
1484 }
1485 }
1486 return NULL;
1487 }
1488
1489 //------------------------------remove_pack_at---------------------------
1490 // Remove the pack at position pos in the packset
1491 void SuperWord::remove_pack_at(int pos) {
1492 Node_List* p = _packset.at(pos);
1493 for (uint i = 0; i < p->size(); i++) {
1494 Node* s = p->at(i);
1495 set_my_pack(s, NULL);
1496 }
1497 _packset.remove_at(pos);
1498 }
1499
1500 //------------------------------executed_first---------------------------
1501 // Return the node executed first in pack p. Uses the RPO block list
1502 // to determine order.
1503 Node* SuperWord::executed_first(Node_List* p) {
1504 Node* n = p->at(0);
1505 int n_rpo = bb_idx(n);
1506 for (uint i = 1; i < p->size(); i++) {
1507 Node* s = p->at(i);
1508 int s_rpo = bb_idx(s);
1509 if (s_rpo < n_rpo) {
1510 n = s;
1511 n_rpo = s_rpo;
1512 }
1513 }
1514 return n;
1515 }
1516
1517 //------------------------------executed_last---------------------------
1518 // Return the node executed last in pack p.
1519 Node* SuperWord::executed_last(Node_List* p) {
1520 Node* n = p->at(0);
1521 int n_rpo = bb_idx(n);
1522 for (uint i = 1; i < p->size(); i++) {
1523 Node* s = p->at(i);
1524 int s_rpo = bb_idx(s);
1525 if (s_rpo > n_rpo) {
1526 n = s;
1527 n_rpo = s_rpo;
1528 }
1529 }
1530 return n;
1531 }
1532
1533 //----------------------------align_initial_loop_index---------------------------
1534 // Adjust pre-loop limit so that in main loop, a load/store reference
1535 // to align_to_ref will be a position zero in the vector.
1536 // (iv + k) mod vector_align == 0
1537 void SuperWord::align_initial_loop_index(MemNode* align_to_ref) {
1538 CountedLoopNode *main_head = lp()->as_CountedLoop();
1539 assert(main_head->is_main_loop(), "");
1540 CountedLoopEndNode* pre_end = get_pre_loop_end(main_head);
1541 assert(pre_end != NULL, "");
1542 Node *pre_opaq1 = pre_end->limit();
1543 assert(pre_opaq1->Opcode() == Op_Opaque1, "");
1544 Opaque1Node *pre_opaq = (Opaque1Node*)pre_opaq1;
1545 Node *pre_limit = pre_opaq->in(1);
1546
1547 // Where we put new limit calculations
1548 Node *pre_ctrl = pre_end->loopnode()->in(LoopNode::EntryControl);
1549
1550 // Ensure the original loop limit is available from the
1551 // pre-loop Opaque1 node.
1552 Node *orig_limit = pre_opaq->original_loop_limit();
1553 assert(orig_limit != NULL && _igvn.type(orig_limit) != Type::TOP, "");
1554
1555 SWPointer align_to_ref_p(align_to_ref, this);
1556
1557 // Let l0 == original pre_limit, l == new pre_limit, V == v_align
1558 //
1559 // For stride > 0
1560 // Need l such that l > l0 && (l+k)%V == 0
1561 // Find n such that l = (l0 + n)
1562 // (l0 + n + k) % V == 0
1563 // n = [V - (l0 + k)%V]%V
1564 // new limit = l0 + [V - (l0 + k)%V]%V
1565 // For stride < 0
1566 // Need l such that l < l0 && (l+k)%V == 0
1567 // Find n such that l = (l0 - n)
1568 // (l0 - n + k) % V == 0
1569 // n = (l0 + k)%V
1570 // new limit = l0 - (l0 + k)%V
1571
1572 int elt_size = align_to_ref_p.memory_size();
1573 int v_align = vector_width_in_bytes() / elt_size;
1574 int k = align_to_ref_p.offset_in_bytes() / elt_size;
1575
1576 Node *kn = _igvn.intcon(k);
1577 Node *limk = new (_phase->C, 3) AddINode(pre_limit, kn);
1578 _phase->_igvn.register_new_node_with_optimizer(limk);
1579 _phase->set_ctrl(limk, pre_ctrl);
1580 if (align_to_ref_p.invar() != NULL) {
1581 Node* log2_elt = _igvn.intcon(exact_log2(elt_size));
1582 Node* aref = new (_phase->C, 3) URShiftINode(align_to_ref_p.invar(), log2_elt);
1583 _phase->_igvn.register_new_node_with_optimizer(aref);
1584 _phase->set_ctrl(aref, pre_ctrl);
1585 if (!align_to_ref_p.negate_invar()) {
1586 limk = new (_phase->C, 3) AddINode(limk, aref);
1587 } else {
1588 limk = new (_phase->C, 3) SubINode(limk, aref);
1589 }
1590 _phase->_igvn.register_new_node_with_optimizer(limk);
1591 _phase->set_ctrl(limk, pre_ctrl);
1592 }
1593 Node* va_msk = _igvn.intcon(v_align - 1);
1594 Node* n = new (_phase->C, 3) AndINode(limk, va_msk);
1595 _phase->_igvn.register_new_node_with_optimizer(n);
1596 _phase->set_ctrl(n, pre_ctrl);
1597 Node* newlim;
1598 if (iv_stride() > 0) {
1599 Node* va = _igvn.intcon(v_align);
1600 Node* adj = new (_phase->C, 3) SubINode(va, n);
1601 _phase->_igvn.register_new_node_with_optimizer(adj);
1602 _phase->set_ctrl(adj, pre_ctrl);
1603 Node* adj2 = new (_phase->C, 3) AndINode(adj, va_msk);
1604 _phase->_igvn.register_new_node_with_optimizer(adj2);
1605 _phase->set_ctrl(adj2, pre_ctrl);
1606 newlim = new (_phase->C, 3) AddINode(pre_limit, adj2);
1607 } else {
1608 newlim = new (_phase->C, 3) SubINode(pre_limit, n);
1609 }
1610 _phase->_igvn.register_new_node_with_optimizer(newlim);
1611 _phase->set_ctrl(newlim, pre_ctrl);
1612 Node* constrained =
1613 (iv_stride() > 0) ? (Node*) new (_phase->C,3) MinINode(newlim, orig_limit)
1614 : (Node*) new (_phase->C,3) MaxINode(newlim, orig_limit);
1615 _phase->_igvn.register_new_node_with_optimizer(constrained);
1616 _phase->set_ctrl(constrained, pre_ctrl);
1617 _igvn.hash_delete(pre_opaq);
1618 pre_opaq->set_req(1, constrained);
1619 }
1620
1621 //----------------------------get_pre_loop_end---------------------------
1622 // Find pre loop end from main loop. Returns null if none.
1623 CountedLoopEndNode* SuperWord::get_pre_loop_end(CountedLoopNode *cl) {
1624 Node *ctrl = cl->in(LoopNode::EntryControl);
1625 if (!ctrl->is_IfTrue() && !ctrl->is_IfFalse()) return NULL;
1626 Node *iffm = ctrl->in(0);
1627 if (!iffm->is_If()) return NULL;
1628 Node *p_f = iffm->in(0);
1629 if (!p_f->is_IfFalse()) return NULL;
1630 if (!p_f->in(0)->is_CountedLoopEnd()) return NULL;
1631 CountedLoopEndNode *pre_end = p_f->in(0)->as_CountedLoopEnd();
1632 if (!pre_end->loopnode()->is_pre_loop()) return NULL;
1633 return pre_end;
1634 }
1635
1636
1637 //------------------------------init---------------------------
1638 void SuperWord::init() {
1639 _dg.init();
1640 _packset.clear();
1641 _disjoint_ptrs.clear();
1642 _block.clear();
1643 _data_entry.clear();
1644 _mem_slice_head.clear();
1645 _mem_slice_tail.clear();
1646 _node_info.clear();
1647 _align_to_ref = NULL;
1648 _lpt = NULL;
1649 _lp = NULL;
1650 _bb = NULL;
1651 _iv = NULL;
1652 }
1653
1654 //------------------------------print_packset---------------------------
1655 void SuperWord::print_packset() {
1656 #ifndef PRODUCT
1657 tty->print_cr("packset");
1658 for (int i = 0; i < _packset.length(); i++) {
1659 tty->print_cr("Pack: %d", i);
1660 Node_List* p = _packset.at(i);
1661 print_pack(p);
1662 }
1663 #endif
1664 }
1665
1666 //------------------------------print_pack---------------------------
1667 void SuperWord::print_pack(Node_List* p) {
1668 for (uint i = 0; i < p->size(); i++) {
1669 print_stmt(p->at(i));
1670 }
1671 }
1672
1673 //------------------------------print_bb---------------------------
1674 void SuperWord::print_bb() {
1675 #ifndef PRODUCT
1676 tty->print_cr("\nBlock");
1677 for (int i = 0; i < _block.length(); i++) {
1678 Node* n = _block.at(i);
1679 tty->print("%d ", i);
1680 if (n) {
1681 n->dump();
1682 }
1683 }
1684 #endif
1685 }
1686
1687 //------------------------------print_stmt---------------------------
1688 void SuperWord::print_stmt(Node* s) {
1689 #ifndef PRODUCT
1690 tty->print(" align: %d \t", alignment(s));
1691 s->dump();
1692 #endif
1693 }
1694
1695 //------------------------------blank---------------------------
1696 char* SuperWord::blank(uint depth) {
1697 static char blanks[101];
1698 assert(depth < 101, "too deep");
1699 for (uint i = 0; i < depth; i++) blanks[i] = ' ';
1700 blanks[depth] = '\0';
1701 return blanks;
1702 }
1703
1704
1705 //==============================SWPointer===========================
1706
1707 //----------------------------SWPointer------------------------
1708 SWPointer::SWPointer(MemNode* mem, SuperWord* slp) :
1709 _mem(mem), _slp(slp), _base(NULL), _adr(NULL),
1710 _scale(0), _offset(0), _invar(NULL), _negate_invar(false) {
1711
1712 Node* adr = mem->in(MemNode::Address);
1713 if (!adr->is_AddP()) {
1714 assert(!valid(), "too complex");
1715 return;
1716 }
1717 // Match AddP(base, AddP(ptr, k*iv [+ invariant]), constant)
1718 Node* base = adr->in(AddPNode::Base);
1719 for (int i = 0; i < 3; i++) {
1720 if (!scaled_iv_plus_offset(adr->in(AddPNode::Offset))) {
1721 assert(!valid(), "too complex");
1722 return;
1723 }
1724 adr = adr->in(AddPNode::Address);
1725 if (base == adr || !adr->is_AddP()) {
1726 break; // stop looking at addp's
1727 }
1728 }
1729 _base = base;
1730 _adr = adr;
1731 assert(valid(), "Usable");
1732 }
1733
1734 // Following is used to create a temporary object during
1735 // the pattern match of an address expression.
1736 SWPointer::SWPointer(SWPointer* p) :
1737 _mem(p->_mem), _slp(p->_slp), _base(NULL), _adr(NULL),
1738 _scale(0), _offset(0), _invar(NULL), _negate_invar(false) {}
1739
1740 //------------------------scaled_iv_plus_offset--------------------
1741 // Match: k*iv + offset
1742 // where: k is a constant that maybe zero, and
1743 // offset is (k2 [+/- invariant]) where k2 maybe zero and invariant is optional
1744 bool SWPointer::scaled_iv_plus_offset(Node* n) {
1745 if (scaled_iv(n)) {
1746 return true;
1747 }
1748 if (offset_plus_k(n)) {
1749 return true;
1750 }
1751 int opc = n->Opcode();
1752 if (opc == Op_AddI) {
1753 if (scaled_iv(n->in(1)) && offset_plus_k(n->in(2))) {
1754 return true;
1755 }
1756 if (scaled_iv(n->in(2)) && offset_plus_k(n->in(1))) {
1757 return true;
1758 }
1759 } else if (opc == Op_SubI) {
1760 if (scaled_iv(n->in(1)) && offset_plus_k(n->in(2), true)) {
1761 return true;
1762 }
1763 if (scaled_iv(n->in(2)) && offset_plus_k(n->in(1))) {
1764 _scale *= -1;
1765 return true;
1766 }
1767 }
1768 return false;
1769 }
1770
1771 //----------------------------scaled_iv------------------------
1772 // Match: k*iv where k is a constant that's not zero
1773 bool SWPointer::scaled_iv(Node* n) {
1774 if (_scale != 0) {
1775 return false; // already found a scale
1776 }
1777 if (n == iv()) {
1778 _scale = 1;
1779 return true;
1780 }
1781 int opc = n->Opcode();
1782 if (opc == Op_MulI) {
1783 if (n->in(1) == iv() && n->in(2)->is_Con()) {
1784 _scale = n->in(2)->get_int();
1785 return true;
1786 } else if (n->in(2) == iv() && n->in(1)->is_Con()) {
1787 _scale = n->in(1)->get_int();
1788 return true;
1789 }
1790 } else if (opc == Op_LShiftI) {
1791 if (n->in(1) == iv() && n->in(2)->is_Con()) {
1792 _scale = 1 << n->in(2)->get_int();
1793 return true;
1794 }
1795 } else if (opc == Op_ConvI2L) {
1796 if (scaled_iv_plus_offset(n->in(1))) {
1797 return true;
1798 }
1799 } else if (opc == Op_LShiftL) {
1800 if (!has_iv() && _invar == NULL) {
1801 // Need to preserve the current _offset value, so
1802 // create a temporary object for this expression subtree.
1803 // Hacky, so should re-engineer the address pattern match.
1804 SWPointer tmp(this);
1805 if (tmp.scaled_iv_plus_offset(n->in(1))) {
1806 if (tmp._invar == NULL) {
1807 int mult = 1 << n->in(2)->get_int();
1808 _scale = tmp._scale * mult;
1809 _offset += tmp._offset * mult;
1810 return true;
1811 }
1812 }
1813 }
1814 }
1815 return false;
1816 }
1817
1818 //----------------------------offset_plus_k------------------------
1819 // Match: offset is (k [+/- invariant])
1820 // where k maybe zero and invariant is optional, but not both.
1821 bool SWPointer::offset_plus_k(Node* n, bool negate) {
1822 int opc = n->Opcode();
1823 if (opc == Op_ConI) {
1824 _offset += negate ? -(n->get_int()) : n->get_int();
1825 return true;
1826 } else if (opc == Op_ConL) {
1827 // Okay if value fits into an int
1828 const TypeLong* t = n->find_long_type();
1829 if (t->higher_equal(TypeLong::INT)) {
1830 jlong loff = n->get_long();
1831 jint off = (jint)loff;
1832 _offset += negate ? -off : loff;
1833 return true;
1834 }
1835 return false;
1836 }
1837 if (_invar != NULL) return false; // already have an invariant
1838 if (opc == Op_AddI) {
1839 if (n->in(2)->is_Con() && invariant(n->in(1))) {
1840 _negate_invar = negate;
1841 _invar = n->in(1);
1842 _offset += negate ? -(n->in(2)->get_int()) : n->in(2)->get_int();
1843 return true;
1844 } else if (n->in(1)->is_Con() && invariant(n->in(2))) {
1845 _offset += negate ? -(n->in(1)->get_int()) : n->in(1)->get_int();
1846 _negate_invar = negate;
1847 _invar = n->in(2);
1848 return true;
1849 }
1850 }
1851 if (opc == Op_SubI) {
1852 if (n->in(2)->is_Con() && invariant(n->in(1))) {
1853 _negate_invar = negate;
1854 _invar = n->in(1);
1855 _offset += !negate ? -(n->in(2)->get_int()) : n->in(2)->get_int();
1856 return true;
1857 } else if (n->in(1)->is_Con() && invariant(n->in(2))) {
1858 _offset += negate ? -(n->in(1)->get_int()) : n->in(1)->get_int();
1859 _negate_invar = !negate;
1860 _invar = n->in(2);
1861 return true;
1862 }
1863 }
1864 if (invariant(n)) {
1865 _negate_invar = negate;
1866 _invar = n;
1867 return true;
1868 }
1869 return false;
1870 }
1871
1872 //----------------------------print------------------------
1873 void SWPointer::print() {
1874 #ifndef PRODUCT
1875 tty->print("base: %d adr: %d scale: %d offset: %d invar: %c%d\n",
1876 _base != NULL ? _base->_idx : 0,
1877 _adr != NULL ? _adr->_idx : 0,
1878 _scale, _offset,
1879 _negate_invar?'-':'+',
1880 _invar != NULL ? _invar->_idx : 0);
1881 #endif
1882 }
1883
1884 // ========================= OrderedPair =====================
1885
1886 const OrderedPair OrderedPair::initial;
1887
1888 // ========================= SWNodeInfo =====================
1889
1890 const SWNodeInfo SWNodeInfo::initial;
1891
1892
1893 // ============================ DepGraph ===========================
1894
1895 //------------------------------make_node---------------------------
1896 // Make a new dependence graph node for an ideal node.
1897 DepMem* DepGraph::make_node(Node* node) {
1898 DepMem* m = new (_arena) DepMem(node);
1899 if (node != NULL) {
1900 assert(_map.at_grow(node->_idx) == NULL, "one init only");
1901 _map.at_put_grow(node->_idx, m);
1902 }
1903 return m;
1904 }
1905
1906 //------------------------------make_edge---------------------------
1907 // Make a new dependence graph edge from dpred -> dsucc
1908 DepEdge* DepGraph::make_edge(DepMem* dpred, DepMem* dsucc) {
1909 DepEdge* e = new (_arena) DepEdge(dpred, dsucc, dsucc->in_head(), dpred->out_head());
1910 dpred->set_out_head(e);
1911 dsucc->set_in_head(e);
1912 return e;
1913 }
1914
1915 // ========================== DepMem ========================
1916
1917 //------------------------------in_cnt---------------------------
1918 int DepMem::in_cnt() {
1919 int ct = 0;
1920 for (DepEdge* e = _in_head; e != NULL; e = e->next_in()) ct++;
1921 return ct;
1922 }
1923
1924 //------------------------------out_cnt---------------------------
1925 int DepMem::out_cnt() {
1926 int ct = 0;
1927 for (DepEdge* e = _out_head; e != NULL; e = e->next_out()) ct++;
1928 return ct;
1929 }
1930
1931 //------------------------------print-----------------------------
1932 void DepMem::print() {
1933 #ifndef PRODUCT
1934 tty->print(" DepNode %d (", _node->_idx);
1935 for (DepEdge* p = _in_head; p != NULL; p = p->next_in()) {
1936 Node* pred = p->pred()->node();
1937 tty->print(" %d", pred != NULL ? pred->_idx : 0);
1938 }
1939 tty->print(") [");
1940 for (DepEdge* s = _out_head; s != NULL; s = s->next_out()) {
1941 Node* succ = s->succ()->node();
1942 tty->print(" %d", succ != NULL ? succ->_idx : 0);
1943 }
1944 tty->print_cr(" ]");
1945 #endif
1946 }
1947
1948 // =========================== DepEdge =========================
1949
1950 //------------------------------DepPreds---------------------------
1951 void DepEdge::print() {
1952 #ifndef PRODUCT
1953 tty->print_cr("DepEdge: %d [ %d ]", _pred->node()->_idx, _succ->node()->_idx);
1954 #endif
1955 }
1956
1957 // =========================== DepPreds =========================
1958 // Iterator over predecessor edges in the dependence graph.
1959
1960 //------------------------------DepPreds---------------------------
1961 DepPreds::DepPreds(Node* n, DepGraph& dg) {
1962 _n = n;
1963 _done = false;
1964 if (_n->is_Store() || _n->is_Load()) {
1965 _next_idx = MemNode::Address;
1966 _end_idx = n->req();
1967 _dep_next = dg.dep(_n)->in_head();
1968 } else if (_n->is_Mem()) {
1969 _next_idx = 0;
1970 _end_idx = 0;
1971 _dep_next = dg.dep(_n)->in_head();
1972 } else {
1973 _next_idx = 1;
1974 _end_idx = _n->req();
1975 _dep_next = NULL;
1976 }
1977 next();
1978 }
1979
1980 //------------------------------next---------------------------
1981 void DepPreds::next() {
1982 if (_dep_next != NULL) {
1983 _current = _dep_next->pred()->node();
1984 _dep_next = _dep_next->next_in();
1985 } else if (_next_idx < _end_idx) {
1986 _current = _n->in(_next_idx++);
1987 } else {
1988 _done = true;
1989 }
1990 }
1991
1992 // =========================== DepSuccs =========================
1993 // Iterator over successor edges in the dependence graph.
1994
1995 //------------------------------DepSuccs---------------------------
1996 DepSuccs::DepSuccs(Node* n, DepGraph& dg) {
1997 _n = n;
1998 _done = false;
1999 if (_n->is_Load()) {
2000 _next_idx = 0;
2001 _end_idx = _n->outcnt();
2002 _dep_next = dg.dep(_n)->out_head();
2003 } else if (_n->is_Mem() || _n->is_Phi() && _n->bottom_type() == Type::MEMORY) {
2004 _next_idx = 0;
2005 _end_idx = 0;
2006 _dep_next = dg.dep(_n)->out_head();
2007 } else {
2008 _next_idx = 0;
2009 _end_idx = _n->outcnt();
2010 _dep_next = NULL;
2011 }
2012 next();
2013 }
2014
2015 //-------------------------------next---------------------------
2016 void DepSuccs::next() {
2017 if (_dep_next != NULL) {
2018 _current = _dep_next->succ()->node();
2019 _dep_next = _dep_next->next_out();
2020 } else if (_next_idx < _end_idx) {
2021 _current = _n->raw_out(_next_idx++);
2022 } else {
2023 _done = true;
2024 }
2025 }