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src/share/vm/opto/superword.cpp@99269dbf4ba8
src/share/vm/opto/superword.cpp
Fri, 14 Mar 2008 15:26:33 -0700
- author
- kvn
- date
- Fri, 14 Mar 2008 15:26:33 -0700
- changeset 500
- 99269dbf4ba8
- parent 464
- d5fc211aea19
- child 507
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6674588: (Escape Analysis) Improve Escape Analysis code
Summary: Current EA code has several problems which have to be fixed.
Reviewed-by: jrose, sgoldman
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 */
24 #include "incls/_precompiled.incl"
25 #include "incls/_superword.cpp.incl"
27 //
28 // S U P E R W O R D T R A N S F O R M
29 //=============================================================================
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 {}
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();
62 if (!cl->is_main_loop() ) return; // skip normal, pre, and post loops
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;
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;
74 // Do vectors exist on this architecture?
75 if (vector_width_in_bytes() == 0) return;
77 init(); // initialize data structures
79 set_lpt(lpt);
80 set_lp(cl);
82 // For now, define one block which is the entire loop body
83 set_bb(cl);
85 assert(_packset.length() == 0, "packset must be empty");
86 SLP_extract();
87 }
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() {
125 // Ready the block
127 construct_bb();
129 dependence_graph();
131 compute_max_depth();
133 compute_vector_element_type();
135 // Attempt vectorization
137 find_adjacent_refs();
139 extend_packlist();
141 combine_packs();
143 construct_my_pack_map();
145 filter_packs();
147 schedule();
149 output();
150 }
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 is_java_primitive(n->as_Mem()->memory_type())) {
164 int align = memory_alignment(n->as_Mem(), 0);
165 if (align != bottom_align) {
166 memops.push(n);
167 }
168 }
169 }
170 if (memops.size() == 0) return;
172 // Find a memory reference to align to. The pre-loop trip count
173 // is modified to align this reference to a vector-aligned address
174 find_align_to_ref(memops);
175 if (align_to_ref() == NULL) return;
177 SWPointer align_to_ref_p(align_to_ref(), this);
178 int offset = align_to_ref_p.offset_in_bytes();
179 int scale = align_to_ref_p.scale_in_bytes();
180 int vw = vector_width_in_bytes();
181 int stride_sign = (scale * iv_stride()) > 0 ? 1 : -1;
182 int iv_adjustment = (stride_sign * vw - (offset % vw)) % vw;
184 #ifndef PRODUCT
185 if (TraceSuperWord)
186 tty->print_cr("\noffset = %d iv_adjustment = %d elt_align = %d",
187 offset, iv_adjustment, align_to_ref_p.memory_size());
188 #endif
190 // Set alignment relative to "align_to_ref"
191 for (int i = memops.size() - 1; i >= 0; i--) {
192 MemNode* s = memops.at(i)->as_Mem();
193 SWPointer p2(s, this);
194 if (p2.comparable(align_to_ref_p)) {
195 int align = memory_alignment(s, iv_adjustment);
196 set_alignment(s, align);
197 } else {
198 memops.remove(i);
199 }
200 }
202 // Create initial pack pairs of memory operations
203 for (uint i = 0; i < memops.size(); i++) {
204 Node* s1 = memops.at(i);
205 for (uint j = 0; j < memops.size(); j++) {
206 Node* s2 = memops.at(j);
207 if (s1 != s2 && are_adjacent_refs(s1, s2)) {
208 int align = alignment(s1);
209 if (stmts_can_pack(s1, s2, align)) {
210 Node_List* pair = new Node_List();
211 pair->push(s1);
212 pair->push(s2);
213 _packset.append(pair);
214 }
215 }
216 }
217 }
219 #ifndef PRODUCT
220 if (TraceSuperWord) {
221 tty->print_cr("\nAfter find_adjacent_refs");
222 print_packset();
223 }
224 #endif
225 }
227 //------------------------------find_align_to_ref---------------------------
228 // Find a memory reference to align the loop induction variable to.
229 // Looks first at stores then at loads, looking for a memory reference
230 // with the largest number of references similar to it.
231 void SuperWord::find_align_to_ref(Node_List &memops) {
232 GrowableArray<int> cmp_ct(arena(), memops.size(), memops.size(), 0);
234 // Count number of comparable memory ops
235 for (uint i = 0; i < memops.size(); i++) {
236 MemNode* s1 = memops.at(i)->as_Mem();
237 SWPointer p1(s1, this);
238 // Discard if pre loop can't align this reference
239 if (!ref_is_alignable(p1)) {
240 *cmp_ct.adr_at(i) = 0;
241 continue;
242 }
243 for (uint j = i+1; j < memops.size(); j++) {
244 MemNode* s2 = memops.at(j)->as_Mem();
245 if (isomorphic(s1, s2)) {
246 SWPointer p2(s2, this);
247 if (p1.comparable(p2)) {
248 (*cmp_ct.adr_at(i))++;
249 (*cmp_ct.adr_at(j))++;
250 }
251 }
252 }
253 }
255 // Find Store (or Load) with the greatest number of "comparable" references
256 int max_ct = 0;
257 int max_idx = -1;
258 int min_size = max_jint;
259 int min_iv_offset = max_jint;
260 for (uint j = 0; j < memops.size(); j++) {
261 MemNode* s = memops.at(j)->as_Mem();
262 if (s->is_Store()) {
263 SWPointer p(s, this);
264 if (cmp_ct.at(j) > max_ct ||
265 cmp_ct.at(j) == max_ct && (data_size(s) < min_size ||
266 data_size(s) == min_size &&
267 p.offset_in_bytes() < min_iv_offset)) {
268 max_ct = cmp_ct.at(j);
269 max_idx = j;
270 min_size = data_size(s);
271 min_iv_offset = p.offset_in_bytes();
272 }
273 }
274 }
275 // If no stores, look at loads
276 if (max_ct == 0) {
277 for (uint j = 0; j < memops.size(); j++) {
278 MemNode* s = memops.at(j)->as_Mem();
279 if (s->is_Load()) {
280 SWPointer p(s, this);
281 if (cmp_ct.at(j) > max_ct ||
282 cmp_ct.at(j) == max_ct && (data_size(s) < min_size ||
283 data_size(s) == min_size &&
284 p.offset_in_bytes() < min_iv_offset)) {
285 max_ct = cmp_ct.at(j);
286 max_idx = j;
287 min_size = data_size(s);
288 min_iv_offset = p.offset_in_bytes();
289 }
290 }
291 }
292 }
294 if (max_ct > 0)
295 set_align_to_ref(memops.at(max_idx)->as_Mem());
297 #ifndef PRODUCT
298 if (TraceSuperWord && Verbose) {
299 tty->print_cr("\nVector memops after find_align_to_refs");
300 for (uint i = 0; i < memops.size(); i++) {
301 MemNode* s = memops.at(i)->as_Mem();
302 s->dump();
303 }
304 }
305 #endif
306 }
308 //------------------------------ref_is_alignable---------------------------
309 // Can the preloop align the reference to position zero in the vector?
310 bool SuperWord::ref_is_alignable(SWPointer& p) {
311 if (!p.has_iv()) {
312 return true; // no induction variable
313 }
314 CountedLoopEndNode* pre_end = get_pre_loop_end(lp()->as_CountedLoop());
315 assert(pre_end->stride_is_con(), "pre loop stride is constant");
316 int preloop_stride = pre_end->stride_con();
318 int span = preloop_stride * p.scale_in_bytes();
320 // Stride one accesses are alignable.
321 if (ABS(span) == p.memory_size())
322 return true;
324 // If initial offset from start of object is computable,
325 // compute alignment within the vector.
326 int vw = vector_width_in_bytes();
327 if (vw % span == 0) {
328 Node* init_nd = pre_end->init_trip();
329 if (init_nd->is_Con() && p.invar() == NULL) {
330 int init = init_nd->bottom_type()->is_int()->get_con();
332 int init_offset = init * p.scale_in_bytes() + p.offset_in_bytes();
333 assert(init_offset >= 0, "positive offset from object start");
335 if (span > 0) {
336 return (vw - (init_offset % vw)) % span == 0;
337 } else {
338 assert(span < 0, "nonzero stride * scale");
339 return (init_offset % vw) % -span == 0;
340 }
341 }
342 }
343 return false;
344 }
346 //---------------------------dependence_graph---------------------------
347 // Construct dependency graph.
348 // Add dependence edges to load/store nodes for memory dependence
349 // A.out()->DependNode.in(1) and DependNode.out()->B.prec(x)
350 void SuperWord::dependence_graph() {
351 // First, assign a dependence node to each memory node
352 for (int i = 0; i < _block.length(); i++ ) {
353 Node *n = _block.at(i);
354 if (n->is_Mem() || n->is_Phi() && n->bottom_type() == Type::MEMORY) {
355 _dg.make_node(n);
356 }
357 }
359 // For each memory slice, create the dependences
360 for (int i = 0; i < _mem_slice_head.length(); i++) {
361 Node* n = _mem_slice_head.at(i);
362 Node* n_tail = _mem_slice_tail.at(i);
364 // Get slice in predecessor order (last is first)
365 mem_slice_preds(n_tail, n, _nlist);
367 // Make the slice dependent on the root
368 DepMem* slice = _dg.dep(n);
369 _dg.make_edge(_dg.root(), slice);
371 // Create a sink for the slice
372 DepMem* slice_sink = _dg.make_node(NULL);
373 _dg.make_edge(slice_sink, _dg.tail());
375 // Now visit each pair of memory ops, creating the edges
376 for (int j = _nlist.length() - 1; j >= 0 ; j--) {
377 Node* s1 = _nlist.at(j);
379 // If no dependency yet, use slice
380 if (_dg.dep(s1)->in_cnt() == 0) {
381 _dg.make_edge(slice, s1);
382 }
383 SWPointer p1(s1->as_Mem(), this);
384 bool sink_dependent = true;
385 for (int k = j - 1; k >= 0; k--) {
386 Node* s2 = _nlist.at(k);
387 if (s1->is_Load() && s2->is_Load())
388 continue;
389 SWPointer p2(s2->as_Mem(), this);
391 int cmp = p1.cmp(p2);
392 if (SuperWordRTDepCheck &&
393 p1.base() != p2.base() && p1.valid() && p2.valid()) {
394 // Create a runtime check to disambiguate
395 OrderedPair pp(p1.base(), p2.base());
396 _disjoint_ptrs.append_if_missing(pp);
397 } else if (!SWPointer::not_equal(cmp)) {
398 // Possibly same address
399 _dg.make_edge(s1, s2);
400 sink_dependent = false;
401 }
402 }
403 if (sink_dependent) {
404 _dg.make_edge(s1, slice_sink);
405 }
406 }
407 #ifndef PRODUCT
408 if (TraceSuperWord) {
409 tty->print_cr("\nDependence graph for slice: %d", n->_idx);
410 for (int q = 0; q < _nlist.length(); q++) {
411 _dg.print(_nlist.at(q));
412 }
413 tty->cr();
414 }
415 #endif
416 _nlist.clear();
417 }
419 #ifndef PRODUCT
420 if (TraceSuperWord) {
421 tty->print_cr("\ndisjoint_ptrs: %s", _disjoint_ptrs.length() > 0 ? "" : "NONE");
422 for (int r = 0; r < _disjoint_ptrs.length(); r++) {
423 _disjoint_ptrs.at(r).print();
424 tty->cr();
425 }
426 tty->cr();
427 }
428 #endif
429 }
431 //---------------------------mem_slice_preds---------------------------
432 // Return a memory slice (node list) in predecessor order starting at "start"
433 void SuperWord::mem_slice_preds(Node* start, Node* stop, GrowableArray<Node*> &preds) {
434 assert(preds.length() == 0, "start empty");
435 Node* n = start;
436 Node* prev = NULL;
437 while (true) {
438 assert(in_bb(n), "must be in block");
439 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
440 Node* out = n->fast_out(i);
441 if (out->is_Load()) {
442 if (in_bb(out)) {
443 preds.push(out);
444 }
445 } else {
446 // FIXME
447 if (out->is_MergeMem() && !in_bb(out)) {
448 // Either unrolling is causing a memory edge not to disappear,
449 // or need to run igvn.optimize() again before SLP
450 } else if (out->is_Phi() && out->bottom_type() == Type::MEMORY && !in_bb(out)) {
451 // Ditto. Not sure what else to check further.
452 } else if (out->Opcode() == Op_StoreCM && out->in(4) == n) {
453 // StoreCM has an input edge used as a precedence edge.
454 // Maybe an issue when oop stores are vectorized.
455 } else {
456 assert(out == prev || prev == NULL, "no branches off of store slice");
457 }
458 }
459 }
460 if (n == stop) break;
461 preds.push(n);
462 prev = n;
463 n = n->in(MemNode::Memory);
464 }
465 }
467 //------------------------------stmts_can_pack---------------------------
468 // Can s1 and s2 be in a pack with s1 immediately preceeding s2 and
469 // s1 aligned at "align"
470 bool SuperWord::stmts_can_pack(Node* s1, Node* s2, int align) {
471 if (isomorphic(s1, s2)) {
472 if (independent(s1, s2)) {
473 if (!exists_at(s1, 0) && !exists_at(s2, 1)) {
474 if (!s1->is_Mem() || are_adjacent_refs(s1, s2)) {
475 int s1_align = alignment(s1);
476 int s2_align = alignment(s2);
477 if (s1_align == top_align || s1_align == align) {
478 if (s2_align == top_align || s2_align == align + data_size(s1)) {
479 return true;
480 }
481 }
482 }
483 }
484 }
485 }
486 return false;
487 }
489 //------------------------------exists_at---------------------------
490 // Does s exist in a pack at position pos?
491 bool SuperWord::exists_at(Node* s, uint pos) {
492 for (int i = 0; i < _packset.length(); i++) {
493 Node_List* p = _packset.at(i);
494 if (p->at(pos) == s) {
495 return true;
496 }
497 }
498 return false;
499 }
501 //------------------------------are_adjacent_refs---------------------------
502 // Is s1 immediately before s2 in memory?
503 bool SuperWord::are_adjacent_refs(Node* s1, Node* s2) {
504 if (!s1->is_Mem() || !s2->is_Mem()) return false;
505 if (!in_bb(s1) || !in_bb(s2)) return false;
506 // FIXME - co_locate_pack fails on Stores in different mem-slices, so
507 // only pack memops that are in the same alias set until that's fixed.
508 if (_phase->C->get_alias_index(s1->as_Mem()->adr_type()) !=
509 _phase->C->get_alias_index(s2->as_Mem()->adr_type()))
510 return false;
511 SWPointer p1(s1->as_Mem(), this);
512 SWPointer p2(s2->as_Mem(), this);
513 if (p1.base() != p2.base() || !p1.comparable(p2)) return false;
514 int diff = p2.offset_in_bytes() - p1.offset_in_bytes();
515 return diff == data_size(s1);
516 }
518 //------------------------------isomorphic---------------------------
519 // Are s1 and s2 similar?
520 bool SuperWord::isomorphic(Node* s1, Node* s2) {
521 if (s1->Opcode() != s2->Opcode()) return false;
522 if (s1->req() != s2->req()) return false;
523 if (s1->in(0) != s2->in(0)) return false;
524 if (velt_type(s1) != velt_type(s2)) return false;
525 return true;
526 }
528 //------------------------------independent---------------------------
529 // Is there no data path from s1 to s2 or s2 to s1?
530 bool SuperWord::independent(Node* s1, Node* s2) {
531 // assert(s1->Opcode() == s2->Opcode(), "check isomorphic first");
532 int d1 = depth(s1);
533 int d2 = depth(s2);
534 if (d1 == d2) return s1 != s2;
535 Node* deep = d1 > d2 ? s1 : s2;
536 Node* shallow = d1 > d2 ? s2 : s1;
538 visited_clear();
540 return independent_path(shallow, deep);
541 }
543 //------------------------------independent_path------------------------------
544 // Helper for independent
545 bool SuperWord::independent_path(Node* shallow, Node* deep, uint dp) {
546 if (dp >= 1000) return false; // stop deep recursion
547 visited_set(deep);
548 int shal_depth = depth(shallow);
549 assert(shal_depth <= depth(deep), "must be");
550 for (DepPreds preds(deep, _dg); !preds.done(); preds.next()) {
551 Node* pred = preds.current();
552 if (in_bb(pred) && !visited_test(pred)) {
553 if (shallow == pred) {
554 return false;
555 }
556 if (shal_depth < depth(pred) && !independent_path(shallow, pred, dp+1)) {
557 return false;
558 }
559 }
560 }
561 return true;
562 }
564 //------------------------------set_alignment---------------------------
565 void SuperWord::set_alignment(Node* s1, Node* s2, int align) {
566 set_alignment(s1, align);
567 set_alignment(s2, align + data_size(s1));
568 }
570 //------------------------------data_size---------------------------
571 int SuperWord::data_size(Node* s) {
572 const Type* t = velt_type(s);
573 BasicType bt = t->array_element_basic_type();
574 int bsize = type2aelembytes(bt);
575 assert(bsize != 0, "valid size");
576 return bsize;
577 }
579 //------------------------------extend_packlist---------------------------
580 // Extend packset by following use->def and def->use links from pack members.
581 void SuperWord::extend_packlist() {
582 bool changed;
583 do {
584 changed = false;
585 for (int i = 0; i < _packset.length(); i++) {
586 Node_List* p = _packset.at(i);
587 changed |= follow_use_defs(p);
588 changed |= follow_def_uses(p);
589 }
590 } while (changed);
592 #ifndef PRODUCT
593 if (TraceSuperWord) {
594 tty->print_cr("\nAfter extend_packlist");
595 print_packset();
596 }
597 #endif
598 }
600 //------------------------------follow_use_defs---------------------------
601 // Extend the packset by visiting operand definitions of nodes in pack p
602 bool SuperWord::follow_use_defs(Node_List* p) {
603 Node* s1 = p->at(0);
604 Node* s2 = p->at(1);
605 assert(p->size() == 2, "just checking");
606 assert(s1->req() == s2->req(), "just checking");
607 assert(alignment(s1) + data_size(s1) == alignment(s2), "just checking");
609 if (s1->is_Load()) return false;
611 int align = alignment(s1);
612 bool changed = false;
613 int start = s1->is_Store() ? MemNode::ValueIn : 1;
614 int end = s1->is_Store() ? MemNode::ValueIn+1 : s1->req();
615 for (int j = start; j < end; j++) {
616 Node* t1 = s1->in(j);
617 Node* t2 = s2->in(j);
618 if (!in_bb(t1) || !in_bb(t2))
619 continue;
620 if (stmts_can_pack(t1, t2, align)) {
621 if (est_savings(t1, t2) >= 0) {
622 Node_List* pair = new Node_List();
623 pair->push(t1);
624 pair->push(t2);
625 _packset.append(pair);
626 set_alignment(t1, t2, align);
627 changed = true;
628 }
629 }
630 }
631 return changed;
632 }
634 //------------------------------follow_def_uses---------------------------
635 // Extend the packset by visiting uses of nodes in pack p
636 bool SuperWord::follow_def_uses(Node_List* p) {
637 bool changed = false;
638 Node* s1 = p->at(0);
639 Node* s2 = p->at(1);
640 assert(p->size() == 2, "just checking");
641 assert(s1->req() == s2->req(), "just checking");
642 assert(alignment(s1) + data_size(s1) == alignment(s2), "just checking");
644 if (s1->is_Store()) return false;
646 int align = alignment(s1);
647 int savings = -1;
648 Node* u1 = NULL;
649 Node* u2 = NULL;
650 for (DUIterator_Fast imax, i = s1->fast_outs(imax); i < imax; i++) {
651 Node* t1 = s1->fast_out(i);
652 if (!in_bb(t1)) continue;
653 for (DUIterator_Fast jmax, j = s2->fast_outs(jmax); j < jmax; j++) {
654 Node* t2 = s2->fast_out(j);
655 if (!in_bb(t2)) continue;
656 if (!opnd_positions_match(s1, t1, s2, t2))
657 continue;
658 if (stmts_can_pack(t1, t2, align)) {
659 int my_savings = est_savings(t1, t2);
660 if (my_savings > savings) {
661 savings = my_savings;
662 u1 = t1;
663 u2 = t2;
664 }
665 }
666 }
667 }
668 if (savings >= 0) {
669 Node_List* pair = new Node_List();
670 pair->push(u1);
671 pair->push(u2);
672 _packset.append(pair);
673 set_alignment(u1, u2, align);
674 changed = true;
675 }
676 return changed;
677 }
679 //---------------------------opnd_positions_match-------------------------
680 // Is the use of d1 in u1 at the same operand position as d2 in u2?
681 bool SuperWord::opnd_positions_match(Node* d1, Node* u1, Node* d2, Node* u2) {
682 uint ct = u1->req();
683 if (ct != u2->req()) return false;
684 uint i1 = 0;
685 uint i2 = 0;
686 do {
687 for (i1++; i1 < ct; i1++) if (u1->in(i1) == d1) break;
688 for (i2++; i2 < ct; i2++) if (u2->in(i2) == d2) break;
689 if (i1 != i2) {
690 return false;
691 }
692 } while (i1 < ct);
693 return true;
694 }
696 //------------------------------est_savings---------------------------
697 // Estimate the savings from executing s1 and s2 as a pack
698 int SuperWord::est_savings(Node* s1, Node* s2) {
699 int save = 2 - 1; // 2 operations per instruction in packed form
701 // inputs
702 for (uint i = 1; i < s1->req(); i++) {
703 Node* x1 = s1->in(i);
704 Node* x2 = s2->in(i);
705 if (x1 != x2) {
706 if (are_adjacent_refs(x1, x2)) {
707 save += adjacent_profit(x1, x2);
708 } else if (!in_packset(x1, x2)) {
709 save -= pack_cost(2);
710 } else {
711 save += unpack_cost(2);
712 }
713 }
714 }
716 // uses of result
717 uint ct = 0;
718 for (DUIterator_Fast imax, i = s1->fast_outs(imax); i < imax; i++) {
719 Node* s1_use = s1->fast_out(i);
720 for (int j = 0; j < _packset.length(); j++) {
721 Node_List* p = _packset.at(j);
722 if (p->at(0) == s1_use) {
723 for (DUIterator_Fast kmax, k = s2->fast_outs(kmax); k < kmax; k++) {
724 Node* s2_use = s2->fast_out(k);
725 if (p->at(p->size()-1) == s2_use) {
726 ct++;
727 if (are_adjacent_refs(s1_use, s2_use)) {
728 save += adjacent_profit(s1_use, s2_use);
729 }
730 }
731 }
732 }
733 }
734 }
736 if (ct < s1->outcnt()) save += unpack_cost(1);
737 if (ct < s2->outcnt()) save += unpack_cost(1);
739 return save;
740 }
742 //------------------------------costs---------------------------
743 int SuperWord::adjacent_profit(Node* s1, Node* s2) { return 2; }
744 int SuperWord::pack_cost(int ct) { return ct; }
745 int SuperWord::unpack_cost(int ct) { return ct; }
747 //------------------------------combine_packs---------------------------
748 // Combine packs A and B with A.last == B.first into A.first..,A.last,B.second,..B.last
749 void SuperWord::combine_packs() {
750 bool changed;
751 do {
752 changed = false;
753 for (int i = 0; i < _packset.length(); i++) {
754 Node_List* p1 = _packset.at(i);
755 if (p1 == NULL) continue;
756 for (int j = 0; j < _packset.length(); j++) {
757 Node_List* p2 = _packset.at(j);
758 if (p2 == NULL) continue;
759 if (p1->at(p1->size()-1) == p2->at(0)) {
760 for (uint k = 1; k < p2->size(); k++) {
761 p1->push(p2->at(k));
762 }
763 _packset.at_put(j, NULL);
764 changed = true;
765 }
766 }
767 }
768 } while (changed);
770 for (int i = _packset.length() - 1; i >= 0; i--) {
771 Node_List* p1 = _packset.at(i);
772 if (p1 == NULL) {
773 _packset.remove_at(i);
774 }
775 }
777 #ifndef PRODUCT
778 if (TraceSuperWord) {
779 tty->print_cr("\nAfter combine_packs");
780 print_packset();
781 }
782 #endif
783 }
785 //-----------------------------construct_my_pack_map--------------------------
786 // Construct the map from nodes to packs. Only valid after the
787 // point where a node is only in one pack (after combine_packs).
788 void SuperWord::construct_my_pack_map() {
789 Node_List* rslt = NULL;
790 for (int i = 0; i < _packset.length(); i++) {
791 Node_List* p = _packset.at(i);
792 for (uint j = 0; j < p->size(); j++) {
793 Node* s = p->at(j);
794 assert(my_pack(s) == NULL, "only in one pack");
795 set_my_pack(s, p);
796 }
797 }
798 }
800 //------------------------------filter_packs---------------------------
801 // Remove packs that are not implemented or not profitable.
802 void SuperWord::filter_packs() {
804 // Remove packs that are not implemented
805 for (int i = _packset.length() - 1; i >= 0; i--) {
806 Node_List* pk = _packset.at(i);
807 bool impl = implemented(pk);
808 if (!impl) {
809 #ifndef PRODUCT
810 if (TraceSuperWord && Verbose) {
811 tty->print_cr("Unimplemented");
812 pk->at(0)->dump();
813 }
814 #endif
815 remove_pack_at(i);
816 }
817 }
819 // Remove packs that are not profitable
820 bool changed;
821 do {
822 changed = false;
823 for (int i = _packset.length() - 1; i >= 0; i--) {
824 Node_List* pk = _packset.at(i);
825 bool prof = profitable(pk);
826 if (!prof) {
827 #ifndef PRODUCT
828 if (TraceSuperWord && Verbose) {
829 tty->print_cr("Unprofitable");
830 pk->at(0)->dump();
831 }
832 #endif
833 remove_pack_at(i);
834 changed = true;
835 }
836 }
837 } while (changed);
839 #ifndef PRODUCT
840 if (TraceSuperWord) {
841 tty->print_cr("\nAfter filter_packs");
842 print_packset();
843 tty->cr();
844 }
845 #endif
846 }
848 //------------------------------implemented---------------------------
849 // Can code be generated for pack p?
850 bool SuperWord::implemented(Node_List* p) {
851 Node* p0 = p->at(0);
852 int vopc = VectorNode::opcode(p0->Opcode(), p->size(), velt_type(p0));
853 return vopc > 0 && Matcher::has_match_rule(vopc);
854 }
856 //------------------------------profitable---------------------------
857 // For pack p, are all operands and all uses (with in the block) vector?
858 bool SuperWord::profitable(Node_List* p) {
859 Node* p0 = p->at(0);
860 uint start, end;
861 vector_opd_range(p0, &start, &end);
863 // Return false if some input is not vector and inside block
864 for (uint i = start; i < end; i++) {
865 if (!is_vector_use(p0, i)) {
866 // For now, return false if not scalar promotion case (inputs are the same.)
867 // Later, implement PackNode and allow differring, non-vector inputs
868 // (maybe just the ones from outside the block.)
869 Node* p0_def = p0->in(i);
870 for (uint j = 1; j < p->size(); j++) {
871 Node* use = p->at(j);
872 Node* def = use->in(i);
873 if (p0_def != def)
874 return false;
875 }
876 }
877 }
878 if (!p0->is_Store()) {
879 // For now, return false if not all uses are vector.
880 // Later, implement ExtractNode and allow non-vector uses (maybe
881 // just the ones outside the block.)
882 for (uint i = 0; i < p->size(); i++) {
883 Node* def = p->at(i);
884 for (DUIterator_Fast jmax, j = def->fast_outs(jmax); j < jmax; j++) {
885 Node* use = def->fast_out(j);
886 for (uint k = 0; k < use->req(); k++) {
887 Node* n = use->in(k);
888 if (def == n) {
889 if (!is_vector_use(use, k)) {
890 return false;
891 }
892 }
893 }
894 }
895 }
896 }
897 return true;
898 }
900 //------------------------------schedule---------------------------
901 // Adjust the memory graph for the packed operations
902 void SuperWord::schedule() {
904 // Co-locate in the memory graph the members of each memory pack
905 for (int i = 0; i < _packset.length(); i++) {
906 co_locate_pack(_packset.at(i));
907 }
908 }
910 //------------------------------co_locate_pack---------------------------
911 // Within a pack, move stores down to the last executed store,
912 // and move loads up to the first executed load.
913 void SuperWord::co_locate_pack(Node_List* pk) {
914 if (pk->at(0)->is_Store()) {
915 // Push Stores down towards last executed pack member
916 MemNode* first = executed_first(pk)->as_Mem();
917 MemNode* last = executed_last(pk)->as_Mem();
918 MemNode* insert_pt = last;
919 MemNode* current = last->in(MemNode::Memory)->as_Mem();
920 while (true) {
921 assert(in_bb(current), "stay in block");
922 Node* my_mem = current->in(MemNode::Memory);
923 if (in_pack(current, pk)) {
924 // Forward users of my memory state to my input memory state
925 _igvn.hash_delete(current);
926 _igvn.hash_delete(my_mem);
927 for (DUIterator i = current->outs(); current->has_out(i); i++) {
928 Node* use = current->out(i);
929 if (use->is_Mem()) {
930 assert(use->in(MemNode::Memory) == current, "must be");
931 _igvn.hash_delete(use);
932 use->set_req(MemNode::Memory, my_mem);
933 _igvn._worklist.push(use);
934 --i; // deleted this edge; rescan position
935 }
936 }
937 // put current immediately before insert_pt
938 current->set_req(MemNode::Memory, insert_pt->in(MemNode::Memory));
939 _igvn.hash_delete(insert_pt);
940 insert_pt->set_req(MemNode::Memory, current);
941 _igvn._worklist.push(insert_pt);
942 _igvn._worklist.push(current);
943 insert_pt = current;
944 }
945 if (current == first) break;
946 current = my_mem->as_Mem();
947 }
948 } else if (pk->at(0)->is_Load()) {
949 // Pull Loads up towards first executed pack member
950 LoadNode* first = executed_first(pk)->as_Load();
951 Node* first_mem = first->in(MemNode::Memory);
952 _igvn.hash_delete(first_mem);
953 // Give each load same memory state as first
954 for (uint i = 0; i < pk->size(); i++) {
955 LoadNode* ld = pk->at(i)->as_Load();
956 _igvn.hash_delete(ld);
957 ld->set_req(MemNode::Memory, first_mem);
958 _igvn._worklist.push(ld);
959 }
960 }
961 }
963 //------------------------------output---------------------------
964 // Convert packs into vector node operations
965 void SuperWord::output() {
966 if (_packset.length() == 0) return;
968 // MUST ENSURE main loop's initial value is properly aligned:
969 // (iv_initial_value + min_iv_offset) % vector_width_in_bytes() == 0
971 align_initial_loop_index(align_to_ref());
973 // Insert extract (unpack) operations for scalar uses
974 for (int i = 0; i < _packset.length(); i++) {
975 insert_extracts(_packset.at(i));
976 }
978 for (int i = 0; i < _block.length(); i++) {
979 Node* n = _block.at(i);
980 Node_List* p = my_pack(n);
981 if (p && n == executed_last(p)) {
982 uint vlen = p->size();
983 Node* vn = NULL;
984 Node* low_adr = p->at(0);
985 Node* first = executed_first(p);
986 if (n->is_Load()) {
987 int opc = n->Opcode();
988 Node* ctl = n->in(MemNode::Control);
989 Node* mem = first->in(MemNode::Memory);
990 Node* adr = low_adr->in(MemNode::Address);
991 const TypePtr* atyp = n->adr_type();
992 vn = VectorLoadNode::make(_phase->C, opc, ctl, mem, adr, atyp, vlen);
994 } else if (n->is_Store()) {
995 // Promote value to be stored to vector
996 VectorNode* val = vector_opd(p, MemNode::ValueIn);
998 int opc = n->Opcode();
999 Node* ctl = n->in(MemNode::Control);
1000 Node* mem = first->in(MemNode::Memory);
1001 Node* adr = low_adr->in(MemNode::Address);
1002 const TypePtr* atyp = n->adr_type();
1003 vn = VectorStoreNode::make(_phase->C, opc, ctl, mem, adr, atyp, val, vlen);
1005 } else if (n->req() == 3) {
1006 // Promote operands to vector
1007 Node* in1 = vector_opd(p, 1);
1008 Node* in2 = vector_opd(p, 2);
1009 vn = VectorNode::make(_phase->C, n->Opcode(), in1, in2, vlen, velt_type(n));
1011 } else {
1012 ShouldNotReachHere();
1013 }
1015 _phase->_igvn.register_new_node_with_optimizer(vn);
1016 _phase->set_ctrl(vn, _phase->get_ctrl(p->at(0)));
1017 for (uint j = 0; j < p->size(); j++) {
1018 Node* pm = p->at(j);
1019 _igvn.hash_delete(pm);
1020 _igvn.subsume_node(pm, vn);
1021 }
1022 _igvn._worklist.push(vn);
1023 }
1024 }
1025 }
1027 //------------------------------vector_opd---------------------------
1028 // Create a vector operand for the nodes in pack p for operand: in(opd_idx)
1029 VectorNode* SuperWord::vector_opd(Node_List* p, int opd_idx) {
1030 Node* p0 = p->at(0);
1031 uint vlen = p->size();
1032 Node* opd = p0->in(opd_idx);
1034 bool same_opd = true;
1035 for (uint i = 1; i < vlen; i++) {
1036 Node* pi = p->at(i);
1037 Node* in = pi->in(opd_idx);
1038 if (opd != in) {
1039 same_opd = false;
1040 break;
1041 }
1042 }
1044 if (same_opd) {
1045 if (opd->is_Vector()) {
1046 return (VectorNode*)opd; // input is matching vector
1047 }
1048 // Convert scalar input to vector. Use p0's type because it's container
1049 // maybe smaller than the operand's container.
1050 const Type* opd_t = velt_type(!in_bb(opd) ? p0 : opd);
1051 const Type* p0_t = velt_type(p0);
1052 if (p0_t->higher_equal(opd_t)) opd_t = p0_t;
1053 VectorNode* vn = VectorNode::scalar2vector(_phase->C, opd, vlen, opd_t);
1055 _phase->_igvn.register_new_node_with_optimizer(vn);
1056 _phase->set_ctrl(vn, _phase->get_ctrl(opd));
1057 return vn;
1058 }
1060 // Insert pack operation
1061 const Type* opd_t = velt_type(!in_bb(opd) ? p0 : opd);
1062 PackNode* pk = PackNode::make(_phase->C, opd, opd_t);
1064 for (uint i = 1; i < vlen; i++) {
1065 Node* pi = p->at(i);
1066 Node* in = pi->in(opd_idx);
1067 assert(my_pack(in) == NULL, "Should already have been unpacked");
1068 assert(opd_t == velt_type(!in_bb(in) ? pi : in), "all same type");
1069 pk->add_opd(in);
1070 }
1071 _phase->_igvn.register_new_node_with_optimizer(pk);
1072 _phase->set_ctrl(pk, _phase->get_ctrl(opd));
1073 return pk;
1074 }
1076 //------------------------------insert_extracts---------------------------
1077 // If a use of pack p is not a vector use, then replace the
1078 // use with an extract operation.
1079 void SuperWord::insert_extracts(Node_List* p) {
1080 if (p->at(0)->is_Store()) return;
1081 assert(_n_idx_list.is_empty(), "empty (node,index) list");
1083 // Inspect each use of each pack member. For each use that is
1084 // not a vector use, replace the use with an extract operation.
1086 for (uint i = 0; i < p->size(); i++) {
1087 Node* def = p->at(i);
1088 for (DUIterator_Fast jmax, j = def->fast_outs(jmax); j < jmax; j++) {
1089 Node* use = def->fast_out(j);
1090 for (uint k = 0; k < use->req(); k++) {
1091 Node* n = use->in(k);
1092 if (def == n) {
1093 if (!is_vector_use(use, k)) {
1094 _n_idx_list.push(use, k);
1095 }
1096 }
1097 }
1098 }
1099 }
1101 while (_n_idx_list.is_nonempty()) {
1102 Node* use = _n_idx_list.node();
1103 int idx = _n_idx_list.index();
1104 _n_idx_list.pop();
1105 Node* def = use->in(idx);
1107 // Insert extract operation
1108 _igvn.hash_delete(def);
1109 _igvn.hash_delete(use);
1110 int def_pos = alignment(def) / data_size(def);
1111 const Type* def_t = velt_type(def);
1113 Node* ex = ExtractNode::make(_phase->C, def, def_pos, def_t);
1114 _phase->_igvn.register_new_node_with_optimizer(ex);
1115 _phase->set_ctrl(ex, _phase->get_ctrl(def));
1116 use->set_req(idx, ex);
1117 _igvn._worklist.push(def);
1118 _igvn._worklist.push(use);
1120 bb_insert_after(ex, bb_idx(def));
1121 set_velt_type(ex, def_t);
1122 }
1123 }
1125 //------------------------------is_vector_use---------------------------
1126 // Is use->in(u_idx) a vector use?
1127 bool SuperWord::is_vector_use(Node* use, int u_idx) {
1128 Node_List* u_pk = my_pack(use);
1129 if (u_pk == NULL) return false;
1130 Node* def = use->in(u_idx);
1131 Node_List* d_pk = my_pack(def);
1132 if (d_pk == NULL) {
1133 // check for scalar promotion
1134 Node* n = u_pk->at(0)->in(u_idx);
1135 for (uint i = 1; i < u_pk->size(); i++) {
1136 if (u_pk->at(i)->in(u_idx) != n) return false;
1137 }
1138 return true;
1139 }
1140 if (u_pk->size() != d_pk->size())
1141 return false;
1142 for (uint i = 0; i < u_pk->size(); i++) {
1143 Node* ui = u_pk->at(i);
1144 Node* di = d_pk->at(i);
1145 if (ui->in(u_idx) != di || alignment(ui) != alignment(di))
1146 return false;
1147 }
1148 return true;
1149 }
1151 //------------------------------construct_bb---------------------------
1152 // Construct reverse postorder list of block members
1153 void SuperWord::construct_bb() {
1154 Node* entry = bb();
1156 assert(_stk.length() == 0, "stk is empty");
1157 assert(_block.length() == 0, "block is empty");
1158 assert(_data_entry.length() == 0, "data_entry is empty");
1159 assert(_mem_slice_head.length() == 0, "mem_slice_head is empty");
1160 assert(_mem_slice_tail.length() == 0, "mem_slice_tail is empty");
1162 // Find non-control nodes with no inputs from within block,
1163 // create a temporary map from node _idx to bb_idx for use
1164 // by the visited and post_visited sets,
1165 // and count number of nodes in block.
1166 int bb_ct = 0;
1167 for (uint i = 0; i < lpt()->_body.size(); i++ ) {
1168 Node *n = lpt()->_body.at(i);
1169 set_bb_idx(n, i); // Create a temporary map
1170 if (in_bb(n)) {
1171 bb_ct++;
1172 if (!n->is_CFG()) {
1173 bool found = false;
1174 for (uint j = 0; j < n->req(); j++) {
1175 Node* def = n->in(j);
1176 if (def && in_bb(def)) {
1177 found = true;
1178 break;
1179 }
1180 }
1181 if (!found) {
1182 assert(n != entry, "can't be entry");
1183 _data_entry.push(n);
1184 }
1185 }
1186 }
1187 }
1189 // Find memory slices (head and tail)
1190 for (DUIterator_Fast imax, i = lp()->fast_outs(imax); i < imax; i++) {
1191 Node *n = lp()->fast_out(i);
1192 if (in_bb(n) && (n->is_Phi() && n->bottom_type() == Type::MEMORY)) {
1193 Node* n_tail = n->in(LoopNode::LoopBackControl);
1194 _mem_slice_head.push(n);
1195 _mem_slice_tail.push(n_tail);
1196 }
1197 }
1199 // Create an RPO list of nodes in block
1201 visited_clear();
1202 post_visited_clear();
1204 // Push all non-control nodes with no inputs from within block, then control entry
1205 for (int j = 0; j < _data_entry.length(); j++) {
1206 Node* n = _data_entry.at(j);
1207 visited_set(n);
1208 _stk.push(n);
1209 }
1210 visited_set(entry);
1211 _stk.push(entry);
1213 // Do a depth first walk over out edges
1214 int rpo_idx = bb_ct - 1;
1215 int size;
1216 while ((size = _stk.length()) > 0) {
1217 Node* n = _stk.top(); // Leave node on stack
1218 if (!visited_test_set(n)) {
1219 // forward arc in graph
1220 } else if (!post_visited_test(n)) {
1221 // cross or back arc
1222 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1223 Node *use = n->fast_out(i);
1224 if (in_bb(use) && !visited_test(use) &&
1225 // Don't go around backedge
1226 (!use->is_Phi() || n == entry)) {
1227 _stk.push(use);
1228 }
1229 }
1230 if (_stk.length() == size) {
1231 // There were no additional uses, post visit node now
1232 _stk.pop(); // Remove node from stack
1233 assert(rpo_idx >= 0, "");
1234 _block.at_put_grow(rpo_idx, n);
1235 rpo_idx--;
1236 post_visited_set(n);
1237 assert(rpo_idx >= 0 || _stk.is_empty(), "");
1238 }
1239 } else {
1240 _stk.pop(); // Remove post-visited node from stack
1241 }
1242 }
1244 // Create real map of block indices for nodes
1245 for (int j = 0; j < _block.length(); j++) {
1246 Node* n = _block.at(j);
1247 set_bb_idx(n, j);
1248 }
1250 initialize_bb(); // Ensure extra info is allocated.
1252 #ifndef PRODUCT
1253 if (TraceSuperWord) {
1254 print_bb();
1255 tty->print_cr("\ndata entry nodes: %s", _data_entry.length() > 0 ? "" : "NONE");
1256 for (int m = 0; m < _data_entry.length(); m++) {
1257 tty->print("%3d ", m);
1258 _data_entry.at(m)->dump();
1259 }
1260 tty->print_cr("\nmemory slices: %s", _mem_slice_head.length() > 0 ? "" : "NONE");
1261 for (int m = 0; m < _mem_slice_head.length(); m++) {
1262 tty->print("%3d ", m); _mem_slice_head.at(m)->dump();
1263 tty->print(" "); _mem_slice_tail.at(m)->dump();
1264 }
1265 }
1266 #endif
1267 assert(rpo_idx == -1 && bb_ct == _block.length(), "all block members found");
1268 }
1270 //------------------------------initialize_bb---------------------------
1271 // Initialize per node info
1272 void SuperWord::initialize_bb() {
1273 Node* last = _block.at(_block.length() - 1);
1274 grow_node_info(bb_idx(last));
1275 }
1277 //------------------------------bb_insert_after---------------------------
1278 // Insert n into block after pos
1279 void SuperWord::bb_insert_after(Node* n, int pos) {
1280 int n_pos = pos + 1;
1281 // Make room
1282 for (int i = _block.length() - 1; i >= n_pos; i--) {
1283 _block.at_put_grow(i+1, _block.at(i));
1284 }
1285 for (int j = _node_info.length() - 1; j >= n_pos; j--) {
1286 _node_info.at_put_grow(j+1, _node_info.at(j));
1287 }
1288 // Set value
1289 _block.at_put_grow(n_pos, n);
1290 _node_info.at_put_grow(n_pos, SWNodeInfo::initial);
1291 // Adjust map from node->_idx to _block index
1292 for (int i = n_pos; i < _block.length(); i++) {
1293 set_bb_idx(_block.at(i), i);
1294 }
1295 }
1297 //------------------------------compute_max_depth---------------------------
1298 // Compute max depth for expressions from beginning of block
1299 // Use to prune search paths during test for independence.
1300 void SuperWord::compute_max_depth() {
1301 int ct = 0;
1302 bool again;
1303 do {
1304 again = false;
1305 for (int i = 0; i < _block.length(); i++) {
1306 Node* n = _block.at(i);
1307 if (!n->is_Phi()) {
1308 int d_orig = depth(n);
1309 int d_in = 0;
1310 for (DepPreds preds(n, _dg); !preds.done(); preds.next()) {
1311 Node* pred = preds.current();
1312 if (in_bb(pred)) {
1313 d_in = MAX2(d_in, depth(pred));
1314 }
1315 }
1316 if (d_in + 1 != d_orig) {
1317 set_depth(n, d_in + 1);
1318 again = true;
1319 }
1320 }
1321 }
1322 ct++;
1323 } while (again);
1324 #ifndef PRODUCT
1325 if (TraceSuperWord && Verbose)
1326 tty->print_cr("compute_max_depth iterated: %d times", ct);
1327 #endif
1328 }
1330 //-------------------------compute_vector_element_type-----------------------
1331 // Compute necessary vector element type for expressions
1332 // This propagates backwards a narrower integer type when the
1333 // upper bits of the value are not needed.
1334 // Example: char a,b,c; a = b + c;
1335 // Normally the type of the add is integer, but for packed character
1336 // operations the type of the add needs to be char.
1337 void SuperWord::compute_vector_element_type() {
1338 #ifndef PRODUCT
1339 if (TraceSuperWord && Verbose)
1340 tty->print_cr("\ncompute_velt_type:");
1341 #endif
1343 // Initial type
1344 for (int i = 0; i < _block.length(); i++) {
1345 Node* n = _block.at(i);
1346 const Type* t = n->is_Mem() ? Type::get_const_basic_type(n->as_Mem()->memory_type())
1347 : _igvn.type(n);
1348 const Type* vt = container_type(t);
1349 set_velt_type(n, vt);
1350 }
1352 // Propagate narrowed type backwards through operations
1353 // that don't depend on higher order bits
1354 for (int i = _block.length() - 1; i >= 0; i--) {
1355 Node* n = _block.at(i);
1356 // Only integer types need be examined
1357 if (n->bottom_type()->isa_int()) {
1358 uint start, end;
1359 vector_opd_range(n, &start, &end);
1360 const Type* vt = velt_type(n);
1362 for (uint j = start; j < end; j++) {
1363 Node* in = n->in(j);
1364 // Don't propagate through a type conversion
1365 if (n->bottom_type() != in->bottom_type())
1366 continue;
1367 switch(in->Opcode()) {
1368 case Op_AddI: case Op_AddL:
1369 case Op_SubI: case Op_SubL:
1370 case Op_MulI: case Op_MulL:
1371 case Op_AndI: case Op_AndL:
1372 case Op_OrI: case Op_OrL:
1373 case Op_XorI: case Op_XorL:
1374 case Op_LShiftI: case Op_LShiftL:
1375 case Op_CMoveI: case Op_CMoveL:
1376 if (in_bb(in)) {
1377 bool same_type = true;
1378 for (DUIterator_Fast kmax, k = in->fast_outs(kmax); k < kmax; k++) {
1379 Node *use = in->fast_out(k);
1380 if (!in_bb(use) || velt_type(use) != vt) {
1381 same_type = false;
1382 break;
1383 }
1384 }
1385 if (same_type) {
1386 set_velt_type(in, vt);
1387 }
1388 }
1389 }
1390 }
1391 }
1392 }
1393 #ifndef PRODUCT
1394 if (TraceSuperWord && Verbose) {
1395 for (int i = 0; i < _block.length(); i++) {
1396 Node* n = _block.at(i);
1397 velt_type(n)->dump();
1398 tty->print("\t");
1399 n->dump();
1400 }
1401 }
1402 #endif
1403 }
1405 //------------------------------memory_alignment---------------------------
1406 // Alignment within a vector memory reference
1407 int SuperWord::memory_alignment(MemNode* s, int iv_adjust_in_bytes) {
1408 SWPointer p(s, this);
1409 if (!p.valid()) {
1410 return bottom_align;
1411 }
1412 int offset = p.offset_in_bytes();
1413 offset += iv_adjust_in_bytes;
1414 int off_rem = offset % vector_width_in_bytes();
1415 int off_mod = off_rem >= 0 ? off_rem : off_rem + vector_width_in_bytes();
1416 return off_mod;
1417 }
1419 //---------------------------container_type---------------------------
1420 // Smallest type containing range of values
1421 const Type* SuperWord::container_type(const Type* t) {
1422 if (t->isa_aryptr()) {
1423 t = t->is_aryptr()->elem();
1424 }
1425 if (t->basic_type() == T_INT) {
1426 if (t->higher_equal(TypeInt::BOOL)) return TypeInt::BOOL;
1427 if (t->higher_equal(TypeInt::BYTE)) return TypeInt::BYTE;
1428 if (t->higher_equal(TypeInt::CHAR)) return TypeInt::CHAR;
1429 if (t->higher_equal(TypeInt::SHORT)) return TypeInt::SHORT;
1430 return TypeInt::INT;
1431 }
1432 return t;
1433 }
1435 //-------------------------vector_opd_range-----------------------
1436 // (Start, end] half-open range defining which operands are vector
1437 void SuperWord::vector_opd_range(Node* n, uint* start, uint* end) {
1438 switch (n->Opcode()) {
1439 case Op_LoadB: case Op_LoadC:
1440 case Op_LoadI: case Op_LoadL:
1441 case Op_LoadF: case Op_LoadD:
1442 case Op_LoadP:
1443 *start = 0;
1444 *end = 0;
1445 return;
1446 case Op_StoreB: case Op_StoreC:
1447 case Op_StoreI: case Op_StoreL:
1448 case Op_StoreF: case Op_StoreD:
1449 case Op_StoreP:
1450 *start = MemNode::ValueIn;
1451 *end = *start + 1;
1452 return;
1453 case Op_LShiftI: case Op_LShiftL:
1454 *start = 1;
1455 *end = 2;
1456 return;
1457 case Op_CMoveI: case Op_CMoveL: case Op_CMoveF: case Op_CMoveD:
1458 *start = 2;
1459 *end = n->req();
1460 return;
1461 }
1462 *start = 1;
1463 *end = n->req(); // default is all operands
1464 }
1466 //------------------------------in_packset---------------------------
1467 // Are s1 and s2 in a pack pair and ordered as s1,s2?
1468 bool SuperWord::in_packset(Node* s1, Node* s2) {
1469 for (int i = 0; i < _packset.length(); i++) {
1470 Node_List* p = _packset.at(i);
1471 assert(p->size() == 2, "must be");
1472 if (p->at(0) == s1 && p->at(p->size()-1) == s2) {
1473 return true;
1474 }
1475 }
1476 return false;
1477 }
1479 //------------------------------in_pack---------------------------
1480 // Is s in pack p?
1481 Node_List* SuperWord::in_pack(Node* s, Node_List* p) {
1482 for (uint i = 0; i < p->size(); i++) {
1483 if (p->at(i) == s) {
1484 return p;
1485 }
1486 }
1487 return NULL;
1488 }
1490 //------------------------------remove_pack_at---------------------------
1491 // Remove the pack at position pos in the packset
1492 void SuperWord::remove_pack_at(int pos) {
1493 Node_List* p = _packset.at(pos);
1494 for (uint i = 0; i < p->size(); i++) {
1495 Node* s = p->at(i);
1496 set_my_pack(s, NULL);
1497 }
1498 _packset.remove_at(pos);
1499 }
1501 //------------------------------executed_first---------------------------
1502 // Return the node executed first in pack p. Uses the RPO block list
1503 // to determine order.
1504 Node* SuperWord::executed_first(Node_List* p) {
1505 Node* n = p->at(0);
1506 int n_rpo = bb_idx(n);
1507 for (uint i = 1; i < p->size(); i++) {
1508 Node* s = p->at(i);
1509 int s_rpo = bb_idx(s);
1510 if (s_rpo < n_rpo) {
1511 n = s;
1512 n_rpo = s_rpo;
1513 }
1514 }
1515 return n;
1516 }
1518 //------------------------------executed_last---------------------------
1519 // Return the node executed last in pack p.
1520 Node* SuperWord::executed_last(Node_List* p) {
1521 Node* n = p->at(0);
1522 int n_rpo = bb_idx(n);
1523 for (uint i = 1; i < p->size(); i++) {
1524 Node* s = p->at(i);
1525 int s_rpo = bb_idx(s);
1526 if (s_rpo > n_rpo) {
1527 n = s;
1528 n_rpo = s_rpo;
1529 }
1530 }
1531 return n;
1532 }
1534 //----------------------------align_initial_loop_index---------------------------
1535 // Adjust pre-loop limit so that in main loop, a load/store reference
1536 // to align_to_ref will be a position zero in the vector.
1537 // (iv + k) mod vector_align == 0
1538 void SuperWord::align_initial_loop_index(MemNode* align_to_ref) {
1539 CountedLoopNode *main_head = lp()->as_CountedLoop();
1540 assert(main_head->is_main_loop(), "");
1541 CountedLoopEndNode* pre_end = get_pre_loop_end(main_head);
1542 assert(pre_end != NULL, "");
1543 Node *pre_opaq1 = pre_end->limit();
1544 assert(pre_opaq1->Opcode() == Op_Opaque1, "");
1545 Opaque1Node *pre_opaq = (Opaque1Node*)pre_opaq1;
1546 Node *pre_limit = pre_opaq->in(1);
1548 // Where we put new limit calculations
1549 Node *pre_ctrl = pre_end->loopnode()->in(LoopNode::EntryControl);
1551 // Ensure the original loop limit is available from the
1552 // pre-loop Opaque1 node.
1553 Node *orig_limit = pre_opaq->original_loop_limit();
1554 assert(orig_limit != NULL && _igvn.type(orig_limit) != Type::TOP, "");
1556 SWPointer align_to_ref_p(align_to_ref, this);
1558 // Let l0 == original pre_limit, l == new pre_limit, V == v_align
1559 //
1560 // For stride > 0
1561 // Need l such that l > l0 && (l+k)%V == 0
1562 // Find n such that l = (l0 + n)
1563 // (l0 + n + k) % V == 0
1564 // n = [V - (l0 + k)%V]%V
1565 // new limit = l0 + [V - (l0 + k)%V]%V
1566 // For stride < 0
1567 // Need l such that l < l0 && (l+k)%V == 0
1568 // Find n such that l = (l0 - n)
1569 // (l0 - n + k) % V == 0
1570 // n = (l0 + k)%V
1571 // new limit = l0 - (l0 + k)%V
1573 int elt_size = align_to_ref_p.memory_size();
1574 int v_align = vector_width_in_bytes() / elt_size;
1575 int k = align_to_ref_p.offset_in_bytes() / elt_size;
1577 Node *kn = _igvn.intcon(k);
1578 Node *limk = new (_phase->C, 3) AddINode(pre_limit, kn);
1579 _phase->_igvn.register_new_node_with_optimizer(limk);
1580 _phase->set_ctrl(limk, pre_ctrl);
1581 if (align_to_ref_p.invar() != NULL) {
1582 Node* log2_elt = _igvn.intcon(exact_log2(elt_size));
1583 Node* aref = new (_phase->C, 3) URShiftINode(align_to_ref_p.invar(), log2_elt);
1584 _phase->_igvn.register_new_node_with_optimizer(aref);
1585 _phase->set_ctrl(aref, pre_ctrl);
1586 if (!align_to_ref_p.negate_invar()) {
1587 limk = new (_phase->C, 3) AddINode(limk, aref);
1588 } else {
1589 limk = new (_phase->C, 3) SubINode(limk, aref);
1590 }
1591 _phase->_igvn.register_new_node_with_optimizer(limk);
1592 _phase->set_ctrl(limk, pre_ctrl);
1593 }
1594 Node* va_msk = _igvn.intcon(v_align - 1);
1595 Node* n = new (_phase->C, 3) AndINode(limk, va_msk);
1596 _phase->_igvn.register_new_node_with_optimizer(n);
1597 _phase->set_ctrl(n, pre_ctrl);
1598 Node* newlim;
1599 if (iv_stride() > 0) {
1600 Node* va = _igvn.intcon(v_align);
1601 Node* adj = new (_phase->C, 3) SubINode(va, n);
1602 _phase->_igvn.register_new_node_with_optimizer(adj);
1603 _phase->set_ctrl(adj, pre_ctrl);
1604 Node* adj2 = new (_phase->C, 3) AndINode(adj, va_msk);
1605 _phase->_igvn.register_new_node_with_optimizer(adj2);
1606 _phase->set_ctrl(adj2, pre_ctrl);
1607 newlim = new (_phase->C, 3) AddINode(pre_limit, adj2);
1608 } else {
1609 newlim = new (_phase->C, 3) SubINode(pre_limit, n);
1610 }
1611 _phase->_igvn.register_new_node_with_optimizer(newlim);
1612 _phase->set_ctrl(newlim, pre_ctrl);
1613 Node* constrained =
1614 (iv_stride() > 0) ? (Node*) new (_phase->C,3) MinINode(newlim, orig_limit)
1615 : (Node*) new (_phase->C,3) MaxINode(newlim, orig_limit);
1616 _phase->_igvn.register_new_node_with_optimizer(constrained);
1617 _phase->set_ctrl(constrained, pre_ctrl);
1618 _igvn.hash_delete(pre_opaq);
1619 pre_opaq->set_req(1, constrained);
1620 }
1622 //----------------------------get_pre_loop_end---------------------------
1623 // Find pre loop end from main loop. Returns null if none.
1624 CountedLoopEndNode* SuperWord::get_pre_loop_end(CountedLoopNode *cl) {
1625 Node *ctrl = cl->in(LoopNode::EntryControl);
1626 if (!ctrl->is_IfTrue() && !ctrl->is_IfFalse()) return NULL;
1627 Node *iffm = ctrl->in(0);
1628 if (!iffm->is_If()) return NULL;
1629 Node *p_f = iffm->in(0);
1630 if (!p_f->is_IfFalse()) return NULL;
1631 if (!p_f->in(0)->is_CountedLoopEnd()) return NULL;
1632 CountedLoopEndNode *pre_end = p_f->in(0)->as_CountedLoopEnd();
1633 if (!pre_end->loopnode()->is_pre_loop()) return NULL;
1634 return pre_end;
1635 }
1638 //------------------------------init---------------------------
1639 void SuperWord::init() {
1640 _dg.init();
1641 _packset.clear();
1642 _disjoint_ptrs.clear();
1643 _block.clear();
1644 _data_entry.clear();
1645 _mem_slice_head.clear();
1646 _mem_slice_tail.clear();
1647 _node_info.clear();
1648 _align_to_ref = NULL;
1649 _lpt = NULL;
1650 _lp = NULL;
1651 _bb = NULL;
1652 _iv = NULL;
1653 }
1655 //------------------------------print_packset---------------------------
1656 void SuperWord::print_packset() {
1657 #ifndef PRODUCT
1658 tty->print_cr("packset");
1659 for (int i = 0; i < _packset.length(); i++) {
1660 tty->print_cr("Pack: %d", i);
1661 Node_List* p = _packset.at(i);
1662 print_pack(p);
1663 }
1664 #endif
1665 }
1667 //------------------------------print_pack---------------------------
1668 void SuperWord::print_pack(Node_List* p) {
1669 for (uint i = 0; i < p->size(); i++) {
1670 print_stmt(p->at(i));
1671 }
1672 }
1674 //------------------------------print_bb---------------------------
1675 void SuperWord::print_bb() {
1676 #ifndef PRODUCT
1677 tty->print_cr("\nBlock");
1678 for (int i = 0; i < _block.length(); i++) {
1679 Node* n = _block.at(i);
1680 tty->print("%d ", i);
1681 if (n) {
1682 n->dump();
1683 }
1684 }
1685 #endif
1686 }
1688 //------------------------------print_stmt---------------------------
1689 void SuperWord::print_stmt(Node* s) {
1690 #ifndef PRODUCT
1691 tty->print(" align: %d \t", alignment(s));
1692 s->dump();
1693 #endif
1694 }
1696 //------------------------------blank---------------------------
1697 char* SuperWord::blank(uint depth) {
1698 static char blanks[101];
1699 assert(depth < 101, "too deep");
1700 for (uint i = 0; i < depth; i++) blanks[i] = ' ';
1701 blanks[depth] = '\0';
1702 return blanks;
1703 }
1706 //==============================SWPointer===========================
1708 //----------------------------SWPointer------------------------
1709 SWPointer::SWPointer(MemNode* mem, SuperWord* slp) :
1710 _mem(mem), _slp(slp), _base(NULL), _adr(NULL),
1711 _scale(0), _offset(0), _invar(NULL), _negate_invar(false) {
1713 Node* adr = mem->in(MemNode::Address);
1714 if (!adr->is_AddP()) {
1715 assert(!valid(), "too complex");
1716 return;
1717 }
1718 // Match AddP(base, AddP(ptr, k*iv [+ invariant]), constant)
1719 Node* base = adr->in(AddPNode::Base);
1720 for (int i = 0; i < 3; i++) {
1721 if (!scaled_iv_plus_offset(adr->in(AddPNode::Offset))) {
1722 assert(!valid(), "too complex");
1723 return;
1724 }
1725 adr = adr->in(AddPNode::Address);
1726 if (base == adr || !adr->is_AddP()) {
1727 break; // stop looking at addp's
1728 }
1729 }
1730 _base = base;
1731 _adr = adr;
1732 assert(valid(), "Usable");
1733 }
1735 // Following is used to create a temporary object during
1736 // the pattern match of an address expression.
1737 SWPointer::SWPointer(SWPointer* p) :
1738 _mem(p->_mem), _slp(p->_slp), _base(NULL), _adr(NULL),
1739 _scale(0), _offset(0), _invar(NULL), _negate_invar(false) {}
1741 //------------------------scaled_iv_plus_offset--------------------
1742 // Match: k*iv + offset
1743 // where: k is a constant that maybe zero, and
1744 // offset is (k2 [+/- invariant]) where k2 maybe zero and invariant is optional
1745 bool SWPointer::scaled_iv_plus_offset(Node* n) {
1746 if (scaled_iv(n)) {
1747 return true;
1748 }
1749 if (offset_plus_k(n)) {
1750 return true;
1751 }
1752 int opc = n->Opcode();
1753 if (opc == Op_AddI) {
1754 if (scaled_iv(n->in(1)) && offset_plus_k(n->in(2))) {
1755 return true;
1756 }
1757 if (scaled_iv(n->in(2)) && offset_plus_k(n->in(1))) {
1758 return true;
1759 }
1760 } else if (opc == Op_SubI) {
1761 if (scaled_iv(n->in(1)) && offset_plus_k(n->in(2), true)) {
1762 return true;
1763 }
1764 if (scaled_iv(n->in(2)) && offset_plus_k(n->in(1))) {
1765 _scale *= -1;
1766 return true;
1767 }
1768 }
1769 return false;
1770 }
1772 //----------------------------scaled_iv------------------------
1773 // Match: k*iv where k is a constant that's not zero
1774 bool SWPointer::scaled_iv(Node* n) {
1775 if (_scale != 0) {
1776 return false; // already found a scale
1777 }
1778 if (n == iv()) {
1779 _scale = 1;
1780 return true;
1781 }
1782 int opc = n->Opcode();
1783 if (opc == Op_MulI) {
1784 if (n->in(1) == iv() && n->in(2)->is_Con()) {
1785 _scale = n->in(2)->get_int();
1786 return true;
1787 } else if (n->in(2) == iv() && n->in(1)->is_Con()) {
1788 _scale = n->in(1)->get_int();
1789 return true;
1790 }
1791 } else if (opc == Op_LShiftI) {
1792 if (n->in(1) == iv() && n->in(2)->is_Con()) {
1793 _scale = 1 << n->in(2)->get_int();
1794 return true;
1795 }
1796 } else if (opc == Op_ConvI2L) {
1797 if (scaled_iv_plus_offset(n->in(1))) {
1798 return true;
1799 }
1800 } else if (opc == Op_LShiftL) {
1801 if (!has_iv() && _invar == NULL) {
1802 // Need to preserve the current _offset value, so
1803 // create a temporary object for this expression subtree.
1804 // Hacky, so should re-engineer the address pattern match.
1805 SWPointer tmp(this);
1806 if (tmp.scaled_iv_plus_offset(n->in(1))) {
1807 if (tmp._invar == NULL) {
1808 int mult = 1 << n->in(2)->get_int();
1809 _scale = tmp._scale * mult;
1810 _offset += tmp._offset * mult;
1811 return true;
1812 }
1813 }
1814 }
1815 }
1816 return false;
1817 }
1819 //----------------------------offset_plus_k------------------------
1820 // Match: offset is (k [+/- invariant])
1821 // where k maybe zero and invariant is optional, but not both.
1822 bool SWPointer::offset_plus_k(Node* n, bool negate) {
1823 int opc = n->Opcode();
1824 if (opc == Op_ConI) {
1825 _offset += negate ? -(n->get_int()) : n->get_int();
1826 return true;
1827 } else if (opc == Op_ConL) {
1828 // Okay if value fits into an int
1829 const TypeLong* t = n->find_long_type();
1830 if (t->higher_equal(TypeLong::INT)) {
1831 jlong loff = n->get_long();
1832 jint off = (jint)loff;
1833 _offset += negate ? -off : loff;
1834 return true;
1835 }
1836 return false;
1837 }
1838 if (_invar != NULL) return false; // already have an invariant
1839 if (opc == Op_AddI) {
1840 if (n->in(2)->is_Con() && invariant(n->in(1))) {
1841 _negate_invar = negate;
1842 _invar = n->in(1);
1843 _offset += negate ? -(n->in(2)->get_int()) : n->in(2)->get_int();
1844 return true;
1845 } else if (n->in(1)->is_Con() && invariant(n->in(2))) {
1846 _offset += negate ? -(n->in(1)->get_int()) : n->in(1)->get_int();
1847 _negate_invar = negate;
1848 _invar = n->in(2);
1849 return true;
1850 }
1851 }
1852 if (opc == Op_SubI) {
1853 if (n->in(2)->is_Con() && invariant(n->in(1))) {
1854 _negate_invar = negate;
1855 _invar = n->in(1);
1856 _offset += !negate ? -(n->in(2)->get_int()) : n->in(2)->get_int();
1857 return true;
1858 } else if (n->in(1)->is_Con() && invariant(n->in(2))) {
1859 _offset += negate ? -(n->in(1)->get_int()) : n->in(1)->get_int();
1860 _negate_invar = !negate;
1861 _invar = n->in(2);
1862 return true;
1863 }
1864 }
1865 if (invariant(n)) {
1866 _negate_invar = negate;
1867 _invar = n;
1868 return true;
1869 }
1870 return false;
1871 }
1873 //----------------------------print------------------------
1874 void SWPointer::print() {
1875 #ifndef PRODUCT
1876 tty->print("base: %d adr: %d scale: %d offset: %d invar: %c%d\n",
1877 _base != NULL ? _base->_idx : 0,
1878 _adr != NULL ? _adr->_idx : 0,
1879 _scale, _offset,
1880 _negate_invar?'-':'+',
1881 _invar != NULL ? _invar->_idx : 0);
1882 #endif
1883 }
1885 // ========================= OrderedPair =====================
1887 const OrderedPair OrderedPair::initial;
1889 // ========================= SWNodeInfo =====================
1891 const SWNodeInfo SWNodeInfo::initial;
1894 // ============================ DepGraph ===========================
1896 //------------------------------make_node---------------------------
1897 // Make a new dependence graph node for an ideal node.
1898 DepMem* DepGraph::make_node(Node* node) {
1899 DepMem* m = new (_arena) DepMem(node);
1900 if (node != NULL) {
1901 assert(_map.at_grow(node->_idx) == NULL, "one init only");
1902 _map.at_put_grow(node->_idx, m);
1903 }
1904 return m;
1905 }
1907 //------------------------------make_edge---------------------------
1908 // Make a new dependence graph edge from dpred -> dsucc
1909 DepEdge* DepGraph::make_edge(DepMem* dpred, DepMem* dsucc) {
1910 DepEdge* e = new (_arena) DepEdge(dpred, dsucc, dsucc->in_head(), dpred->out_head());
1911 dpred->set_out_head(e);
1912 dsucc->set_in_head(e);
1913 return e;
1914 }
1916 // ========================== DepMem ========================
1918 //------------------------------in_cnt---------------------------
1919 int DepMem::in_cnt() {
1920 int ct = 0;
1921 for (DepEdge* e = _in_head; e != NULL; e = e->next_in()) ct++;
1922 return ct;
1923 }
1925 //------------------------------out_cnt---------------------------
1926 int DepMem::out_cnt() {
1927 int ct = 0;
1928 for (DepEdge* e = _out_head; e != NULL; e = e->next_out()) ct++;
1929 return ct;
1930 }
1932 //------------------------------print-----------------------------
1933 void DepMem::print() {
1934 #ifndef PRODUCT
1935 tty->print(" DepNode %d (", _node->_idx);
1936 for (DepEdge* p = _in_head; p != NULL; p = p->next_in()) {
1937 Node* pred = p->pred()->node();
1938 tty->print(" %d", pred != NULL ? pred->_idx : 0);
1939 }
1940 tty->print(") [");
1941 for (DepEdge* s = _out_head; s != NULL; s = s->next_out()) {
1942 Node* succ = s->succ()->node();
1943 tty->print(" %d", succ != NULL ? succ->_idx : 0);
1944 }
1945 tty->print_cr(" ]");
1946 #endif
1947 }
1949 // =========================== DepEdge =========================
1951 //------------------------------DepPreds---------------------------
1952 void DepEdge::print() {
1953 #ifndef PRODUCT
1954 tty->print_cr("DepEdge: %d [ %d ]", _pred->node()->_idx, _succ->node()->_idx);
1955 #endif
1956 }
1958 // =========================== DepPreds =========================
1959 // Iterator over predecessor edges in the dependence graph.
1961 //------------------------------DepPreds---------------------------
1962 DepPreds::DepPreds(Node* n, DepGraph& dg) {
1963 _n = n;
1964 _done = false;
1965 if (_n->is_Store() || _n->is_Load()) {
1966 _next_idx = MemNode::Address;
1967 _end_idx = n->req();
1968 _dep_next = dg.dep(_n)->in_head();
1969 } else if (_n->is_Mem()) {
1970 _next_idx = 0;
1971 _end_idx = 0;
1972 _dep_next = dg.dep(_n)->in_head();
1973 } else {
1974 _next_idx = 1;
1975 _end_idx = _n->req();
1976 _dep_next = NULL;
1977 }
1978 next();
1979 }
1981 //------------------------------next---------------------------
1982 void DepPreds::next() {
1983 if (_dep_next != NULL) {
1984 _current = _dep_next->pred()->node();
1985 _dep_next = _dep_next->next_in();
1986 } else if (_next_idx < _end_idx) {
1987 _current = _n->in(_next_idx++);
1988 } else {
1989 _done = true;
1990 }
1991 }
1993 // =========================== DepSuccs =========================
1994 // Iterator over successor edges in the dependence graph.
1996 //------------------------------DepSuccs---------------------------
1997 DepSuccs::DepSuccs(Node* n, DepGraph& dg) {
1998 _n = n;
1999 _done = false;
2000 if (_n->is_Load()) {
2001 _next_idx = 0;
2002 _end_idx = _n->outcnt();
2003 _dep_next = dg.dep(_n)->out_head();
2004 } else if (_n->is_Mem() || _n->is_Phi() && _n->bottom_type() == Type::MEMORY) {
2005 _next_idx = 0;
2006 _end_idx = 0;
2007 _dep_next = dg.dep(_n)->out_head();
2008 } else {
2009 _next_idx = 0;
2010 _end_idx = _n->outcnt();
2011 _dep_next = NULL;
2012 }
2013 next();
2014 }
2016 //-------------------------------next---------------------------
2017 void DepSuccs::next() {
2018 if (_dep_next != NULL) {
2019 _current = _dep_next->succ()->node();
2020 _dep_next = _dep_next->next_out();
2021 } else if (_next_idx < _end_idx) {
2022 _current = _n->raw_out(_next_idx++);
2023 } else {
2024 _done = true;
2025 }
2026 }
