Tue, 02 Sep 2014 12:48:45 -0700
8055494: Add C2 x86 intrinsic for BigInteger::multiplyToLen() method
Summary: Add new C2 intrinsic for BigInteger::multiplyToLen() on x86 in 64-bit VM.
Reviewed-by: roland
1 /*
2 * Copyright (c) 2007, 2013, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
24 #include "precompiled.hpp"
25 #include "compiler/compileLog.hpp"
26 #include "libadt/vectset.hpp"
27 #include "memory/allocation.inline.hpp"
28 #include "opto/addnode.hpp"
29 #include "opto/callnode.hpp"
30 #include "opto/divnode.hpp"
31 #include "opto/matcher.hpp"
32 #include "opto/memnode.hpp"
33 #include "opto/mulnode.hpp"
34 #include "opto/opcodes.hpp"
35 #include "opto/superword.hpp"
36 #include "opto/vectornode.hpp"
38 //
39 // S U P E R W O R D T R A N S F O R M
40 //=============================================================================
42 //------------------------------SuperWord---------------------------
43 SuperWord::SuperWord(PhaseIdealLoop* phase) :
44 _phase(phase),
45 _igvn(phase->_igvn),
46 _arena(phase->C->comp_arena()),
47 _packset(arena(), 8, 0, NULL), // packs for the current block
48 _bb_idx(arena(), (int)(1.10 * phase->C->unique()), 0, 0), // node idx to index in bb
49 _block(arena(), 8, 0, NULL), // nodes in current block
50 _data_entry(arena(), 8, 0, NULL), // nodes with all inputs from outside
51 _mem_slice_head(arena(), 8, 0, NULL), // memory slice heads
52 _mem_slice_tail(arena(), 8, 0, NULL), // memory slice tails
53 _node_info(arena(), 8, 0, SWNodeInfo::initial), // info needed per node
54 _align_to_ref(NULL), // memory reference to align vectors to
55 _disjoint_ptrs(arena(), 8, 0, OrderedPair::initial), // runtime disambiguated pointer pairs
56 _dg(_arena), // dependence graph
57 _visited(arena()), // visited node set
58 _post_visited(arena()), // post visited node set
59 _n_idx_list(arena(), 8), // scratch list of (node,index) pairs
60 _stk(arena(), 8, 0, NULL), // scratch stack of nodes
61 _nlist(arena(), 8, 0, NULL), // scratch list of nodes
62 _lpt(NULL), // loop tree node
63 _lp(NULL), // LoopNode
64 _bb(NULL), // basic block
65 _iv(NULL) // induction var
66 {}
68 //------------------------------transform_loop---------------------------
69 void SuperWord::transform_loop(IdealLoopTree* lpt) {
70 assert(UseSuperWord, "should be");
71 // Do vectors exist on this architecture?
72 if (Matcher::vector_width_in_bytes(T_BYTE) < 2) return;
74 assert(lpt->_head->is_CountedLoop(), "must be");
75 CountedLoopNode *cl = lpt->_head->as_CountedLoop();
77 if (!cl->is_valid_counted_loop()) return; // skip malformed counted loop
79 if (!cl->is_main_loop() ) return; // skip normal, pre, and post loops
81 // Check for no control flow in body (other than exit)
82 Node *cl_exit = cl->loopexit();
83 if (cl_exit->in(0) != lpt->_head) return;
85 // Make sure the are no extra control users of the loop backedge
86 if (cl->back_control()->outcnt() != 1) {
87 return;
88 }
90 // Check for pre-loop ending with CountedLoopEnd(Bool(Cmp(x,Opaque1(limit))))
91 CountedLoopEndNode* pre_end = get_pre_loop_end(cl);
92 if (pre_end == NULL) return;
93 Node *pre_opaq1 = pre_end->limit();
94 if (pre_opaq1->Opcode() != Op_Opaque1) return;
96 init(); // initialize data structures
98 set_lpt(lpt);
99 set_lp(cl);
101 // For now, define one block which is the entire loop body
102 set_bb(cl);
104 assert(_packset.length() == 0, "packset must be empty");
105 SLP_extract();
106 }
108 //------------------------------SLP_extract---------------------------
109 // Extract the superword level parallelism
110 //
111 // 1) A reverse post-order of nodes in the block is constructed. By scanning
112 // this list from first to last, all definitions are visited before their uses.
113 //
114 // 2) A point-to-point dependence graph is constructed between memory references.
115 // This simplies the upcoming "independence" checker.
116 //
117 // 3) The maximum depth in the node graph from the beginning of the block
118 // to each node is computed. This is used to prune the graph search
119 // in the independence checker.
120 //
121 // 4) For integer types, the necessary bit width is propagated backwards
122 // from stores to allow packed operations on byte, char, and short
123 // integers. This reverses the promotion to type "int" that javac
124 // did for operations like: char c1,c2,c3; c1 = c2 + c3.
125 //
126 // 5) One of the memory references is picked to be an aligned vector reference.
127 // The pre-loop trip count is adjusted to align this reference in the
128 // unrolled body.
129 //
130 // 6) The initial set of pack pairs is seeded with memory references.
131 //
132 // 7) The set of pack pairs is extended by following use->def and def->use links.
133 //
134 // 8) The pairs are combined into vector sized packs.
135 //
136 // 9) Reorder the memory slices to co-locate members of the memory packs.
137 //
138 // 10) Generate ideal vector nodes for the final set of packs and where necessary,
139 // inserting scalar promotion, vector creation from multiple scalars, and
140 // extraction of scalar values from vectors.
141 //
142 void SuperWord::SLP_extract() {
144 // Ready the block
146 if (!construct_bb())
147 return; // Exit if no interesting nodes or complex graph.
149 dependence_graph();
151 compute_max_depth();
153 compute_vector_element_type();
155 // Attempt vectorization
157 find_adjacent_refs();
159 extend_packlist();
161 combine_packs();
163 construct_my_pack_map();
165 filter_packs();
167 schedule();
169 output();
170 }
172 //------------------------------find_adjacent_refs---------------------------
173 // Find the adjacent memory references and create pack pairs for them.
174 // This is the initial set of packs that will then be extended by
175 // following use->def and def->use links. The align positions are
176 // assigned relative to the reference "align_to_ref"
177 void SuperWord::find_adjacent_refs() {
178 // Get list of memory operations
179 Node_List memops;
180 for (int i = 0; i < _block.length(); i++) {
181 Node* n = _block.at(i);
182 if (n->is_Mem() && !n->is_LoadStore() && in_bb(n) &&
183 is_java_primitive(n->as_Mem()->memory_type())) {
184 int align = memory_alignment(n->as_Mem(), 0);
185 if (align != bottom_align) {
186 memops.push(n);
187 }
188 }
189 }
191 Node_List align_to_refs;
192 int best_iv_adjustment = 0;
193 MemNode* best_align_to_mem_ref = NULL;
195 while (memops.size() != 0) {
196 // Find a memory reference to align to.
197 MemNode* mem_ref = find_align_to_ref(memops);
198 if (mem_ref == NULL) break;
199 align_to_refs.push(mem_ref);
200 int iv_adjustment = get_iv_adjustment(mem_ref);
202 if (best_align_to_mem_ref == NULL) {
203 // Set memory reference which is the best from all memory operations
204 // to be used for alignment. The pre-loop trip count is modified to align
205 // this reference to a vector-aligned address.
206 best_align_to_mem_ref = mem_ref;
207 best_iv_adjustment = iv_adjustment;
208 }
210 SWPointer align_to_ref_p(mem_ref, this);
211 // Set alignment relative to "align_to_ref" for all related memory operations.
212 for (int i = memops.size() - 1; i >= 0; i--) {
213 MemNode* s = memops.at(i)->as_Mem();
214 if (isomorphic(s, mem_ref)) {
215 SWPointer p2(s, this);
216 if (p2.comparable(align_to_ref_p)) {
217 int align = memory_alignment(s, iv_adjustment);
218 set_alignment(s, align);
219 }
220 }
221 }
223 // Create initial pack pairs of memory operations for which
224 // alignment is set and vectors will be aligned.
225 bool create_pack = true;
226 if (memory_alignment(mem_ref, best_iv_adjustment) == 0) {
227 if (!Matcher::misaligned_vectors_ok()) {
228 int vw = vector_width(mem_ref);
229 int vw_best = vector_width(best_align_to_mem_ref);
230 if (vw > vw_best) {
231 // Do not vectorize a memory access with more elements per vector
232 // if unaligned memory access is not allowed because number of
233 // iterations in pre-loop will be not enough to align it.
234 create_pack = false;
235 }
236 }
237 } else {
238 if (same_velt_type(mem_ref, best_align_to_mem_ref)) {
239 // Can't allow vectorization of unaligned memory accesses with the
240 // same type since it could be overlapped accesses to the same array.
241 create_pack = false;
242 } else {
243 // Allow independent (different type) unaligned memory operations
244 // if HW supports them.
245 if (!Matcher::misaligned_vectors_ok()) {
246 create_pack = false;
247 } else {
248 // Check if packs of the same memory type but
249 // with a different alignment were created before.
250 for (uint i = 0; i < align_to_refs.size(); i++) {
251 MemNode* mr = align_to_refs.at(i)->as_Mem();
252 if (same_velt_type(mr, mem_ref) &&
253 memory_alignment(mr, iv_adjustment) != 0)
254 create_pack = false;
255 }
256 }
257 }
258 }
259 if (create_pack) {
260 for (uint i = 0; i < memops.size(); i++) {
261 Node* s1 = memops.at(i);
262 int align = alignment(s1);
263 if (align == top_align) continue;
264 for (uint j = 0; j < memops.size(); j++) {
265 Node* s2 = memops.at(j);
266 if (alignment(s2) == top_align) continue;
267 if (s1 != s2 && are_adjacent_refs(s1, s2)) {
268 if (stmts_can_pack(s1, s2, align)) {
269 Node_List* pair = new Node_List();
270 pair->push(s1);
271 pair->push(s2);
272 _packset.append(pair);
273 }
274 }
275 }
276 }
277 } else { // Don't create unaligned pack
278 // First, remove remaining memory ops of the same type from the list.
279 for (int i = memops.size() - 1; i >= 0; i--) {
280 MemNode* s = memops.at(i)->as_Mem();
281 if (same_velt_type(s, mem_ref)) {
282 memops.remove(i);
283 }
284 }
286 // Second, remove already constructed packs of the same type.
287 for (int i = _packset.length() - 1; i >= 0; i--) {
288 Node_List* p = _packset.at(i);
289 MemNode* s = p->at(0)->as_Mem();
290 if (same_velt_type(s, mem_ref)) {
291 remove_pack_at(i);
292 }
293 }
295 // If needed find the best memory reference for loop alignment again.
296 if (same_velt_type(mem_ref, best_align_to_mem_ref)) {
297 // Put memory ops from remaining packs back on memops list for
298 // the best alignment search.
299 uint orig_msize = memops.size();
300 for (int i = 0; i < _packset.length(); i++) {
301 Node_List* p = _packset.at(i);
302 MemNode* s = p->at(0)->as_Mem();
303 assert(!same_velt_type(s, mem_ref), "sanity");
304 memops.push(s);
305 }
306 MemNode* best_align_to_mem_ref = find_align_to_ref(memops);
307 if (best_align_to_mem_ref == NULL) break;
308 best_iv_adjustment = get_iv_adjustment(best_align_to_mem_ref);
309 // Restore list.
310 while (memops.size() > orig_msize)
311 (void)memops.pop();
312 }
313 } // unaligned memory accesses
315 // Remove used mem nodes.
316 for (int i = memops.size() - 1; i >= 0; i--) {
317 MemNode* m = memops.at(i)->as_Mem();
318 if (alignment(m) != top_align) {
319 memops.remove(i);
320 }
321 }
323 } // while (memops.size() != 0
324 set_align_to_ref(best_align_to_mem_ref);
326 #ifndef PRODUCT
327 if (TraceSuperWord) {
328 tty->print_cr("\nAfter find_adjacent_refs");
329 print_packset();
330 }
331 #endif
332 }
334 //------------------------------find_align_to_ref---------------------------
335 // Find a memory reference to align the loop induction variable to.
336 // Looks first at stores then at loads, looking for a memory reference
337 // with the largest number of references similar to it.
338 MemNode* SuperWord::find_align_to_ref(Node_List &memops) {
339 GrowableArray<int> cmp_ct(arena(), memops.size(), memops.size(), 0);
341 // Count number of comparable memory ops
342 for (uint i = 0; i < memops.size(); i++) {
343 MemNode* s1 = memops.at(i)->as_Mem();
344 SWPointer p1(s1, this);
345 // Discard if pre loop can't align this reference
346 if (!ref_is_alignable(p1)) {
347 *cmp_ct.adr_at(i) = 0;
348 continue;
349 }
350 for (uint j = i+1; j < memops.size(); j++) {
351 MemNode* s2 = memops.at(j)->as_Mem();
352 if (isomorphic(s1, s2)) {
353 SWPointer p2(s2, this);
354 if (p1.comparable(p2)) {
355 (*cmp_ct.adr_at(i))++;
356 (*cmp_ct.adr_at(j))++;
357 }
358 }
359 }
360 }
362 // Find Store (or Load) with the greatest number of "comparable" references,
363 // biggest vector size, smallest data size and smallest iv offset.
364 int max_ct = 0;
365 int max_vw = 0;
366 int max_idx = -1;
367 int min_size = max_jint;
368 int min_iv_offset = max_jint;
369 for (uint j = 0; j < memops.size(); j++) {
370 MemNode* s = memops.at(j)->as_Mem();
371 if (s->is_Store()) {
372 int vw = vector_width_in_bytes(s);
373 assert(vw > 1, "sanity");
374 SWPointer p(s, this);
375 if (cmp_ct.at(j) > max_ct ||
376 cmp_ct.at(j) == max_ct &&
377 (vw > max_vw ||
378 vw == max_vw &&
379 (data_size(s) < min_size ||
380 data_size(s) == min_size &&
381 (p.offset_in_bytes() < min_iv_offset)))) {
382 max_ct = cmp_ct.at(j);
383 max_vw = vw;
384 max_idx = j;
385 min_size = data_size(s);
386 min_iv_offset = p.offset_in_bytes();
387 }
388 }
389 }
390 // If no stores, look at loads
391 if (max_ct == 0) {
392 for (uint j = 0; j < memops.size(); j++) {
393 MemNode* s = memops.at(j)->as_Mem();
394 if (s->is_Load()) {
395 int vw = vector_width_in_bytes(s);
396 assert(vw > 1, "sanity");
397 SWPointer p(s, this);
398 if (cmp_ct.at(j) > max_ct ||
399 cmp_ct.at(j) == max_ct &&
400 (vw > max_vw ||
401 vw == max_vw &&
402 (data_size(s) < min_size ||
403 data_size(s) == min_size &&
404 (p.offset_in_bytes() < min_iv_offset)))) {
405 max_ct = cmp_ct.at(j);
406 max_vw = vw;
407 max_idx = j;
408 min_size = data_size(s);
409 min_iv_offset = p.offset_in_bytes();
410 }
411 }
412 }
413 }
415 #ifdef ASSERT
416 if (TraceSuperWord && Verbose) {
417 tty->print_cr("\nVector memops after find_align_to_refs");
418 for (uint i = 0; i < memops.size(); i++) {
419 MemNode* s = memops.at(i)->as_Mem();
420 s->dump();
421 }
422 }
423 #endif
425 if (max_ct > 0) {
426 #ifdef ASSERT
427 if (TraceSuperWord) {
428 tty->print("\nVector align to node: ");
429 memops.at(max_idx)->as_Mem()->dump();
430 }
431 #endif
432 return memops.at(max_idx)->as_Mem();
433 }
434 return NULL;
435 }
437 //------------------------------ref_is_alignable---------------------------
438 // Can the preloop align the reference to position zero in the vector?
439 bool SuperWord::ref_is_alignable(SWPointer& p) {
440 if (!p.has_iv()) {
441 return true; // no induction variable
442 }
443 CountedLoopEndNode* pre_end = get_pre_loop_end(lp()->as_CountedLoop());
444 assert(pre_end->stride_is_con(), "pre loop stride is constant");
445 int preloop_stride = pre_end->stride_con();
447 int span = preloop_stride * p.scale_in_bytes();
449 // Stride one accesses are alignable.
450 if (ABS(span) == p.memory_size())
451 return true;
453 // If initial offset from start of object is computable,
454 // compute alignment within the vector.
455 int vw = vector_width_in_bytes(p.mem());
456 assert(vw > 1, "sanity");
457 if (vw % span == 0) {
458 Node* init_nd = pre_end->init_trip();
459 if (init_nd->is_Con() && p.invar() == NULL) {
460 int init = init_nd->bottom_type()->is_int()->get_con();
462 int init_offset = init * p.scale_in_bytes() + p.offset_in_bytes();
463 assert(init_offset >= 0, "positive offset from object start");
465 if (span > 0) {
466 return (vw - (init_offset % vw)) % span == 0;
467 } else {
468 assert(span < 0, "nonzero stride * scale");
469 return (init_offset % vw) % -span == 0;
470 }
471 }
472 }
473 return false;
474 }
476 //---------------------------get_iv_adjustment---------------------------
477 // Calculate loop's iv adjustment for this memory ops.
478 int SuperWord::get_iv_adjustment(MemNode* mem_ref) {
479 SWPointer align_to_ref_p(mem_ref, this);
480 int offset = align_to_ref_p.offset_in_bytes();
481 int scale = align_to_ref_p.scale_in_bytes();
482 int vw = vector_width_in_bytes(mem_ref);
483 assert(vw > 1, "sanity");
484 int stride_sign = (scale * iv_stride()) > 0 ? 1 : -1;
485 // At least one iteration is executed in pre-loop by default. As result
486 // several iterations are needed to align memory operations in main-loop even
487 // if offset is 0.
488 int iv_adjustment_in_bytes = (stride_sign * vw - (offset % vw));
489 int elt_size = align_to_ref_p.memory_size();
490 assert(((ABS(iv_adjustment_in_bytes) % elt_size) == 0),
491 err_msg_res("(%d) should be divisible by (%d)", iv_adjustment_in_bytes, elt_size));
492 int iv_adjustment = iv_adjustment_in_bytes/elt_size;
494 #ifndef PRODUCT
495 if (TraceSuperWord)
496 tty->print_cr("\noffset = %d iv_adjust = %d elt_size = %d scale = %d iv_stride = %d vect_size %d",
497 offset, iv_adjustment, elt_size, scale, iv_stride(), vw);
498 #endif
499 return iv_adjustment;
500 }
502 //---------------------------dependence_graph---------------------------
503 // Construct dependency graph.
504 // Add dependence edges to load/store nodes for memory dependence
505 // A.out()->DependNode.in(1) and DependNode.out()->B.prec(x)
506 void SuperWord::dependence_graph() {
507 // First, assign a dependence node to each memory node
508 for (int i = 0; i < _block.length(); i++ ) {
509 Node *n = _block.at(i);
510 if (n->is_Mem() || n->is_Phi() && n->bottom_type() == Type::MEMORY) {
511 _dg.make_node(n);
512 }
513 }
515 // For each memory slice, create the dependences
516 for (int i = 0; i < _mem_slice_head.length(); i++) {
517 Node* n = _mem_slice_head.at(i);
518 Node* n_tail = _mem_slice_tail.at(i);
520 // Get slice in predecessor order (last is first)
521 mem_slice_preds(n_tail, n, _nlist);
523 // Make the slice dependent on the root
524 DepMem* slice = _dg.dep(n);
525 _dg.make_edge(_dg.root(), slice);
527 // Create a sink for the slice
528 DepMem* slice_sink = _dg.make_node(NULL);
529 _dg.make_edge(slice_sink, _dg.tail());
531 // Now visit each pair of memory ops, creating the edges
532 for (int j = _nlist.length() - 1; j >= 0 ; j--) {
533 Node* s1 = _nlist.at(j);
535 // If no dependency yet, use slice
536 if (_dg.dep(s1)->in_cnt() == 0) {
537 _dg.make_edge(slice, s1);
538 }
539 SWPointer p1(s1->as_Mem(), this);
540 bool sink_dependent = true;
541 for (int k = j - 1; k >= 0; k--) {
542 Node* s2 = _nlist.at(k);
543 if (s1->is_Load() && s2->is_Load())
544 continue;
545 SWPointer p2(s2->as_Mem(), this);
547 int cmp = p1.cmp(p2);
548 if (SuperWordRTDepCheck &&
549 p1.base() != p2.base() && p1.valid() && p2.valid()) {
550 // Create a runtime check to disambiguate
551 OrderedPair pp(p1.base(), p2.base());
552 _disjoint_ptrs.append_if_missing(pp);
553 } else if (!SWPointer::not_equal(cmp)) {
554 // Possibly same address
555 _dg.make_edge(s1, s2);
556 sink_dependent = false;
557 }
558 }
559 if (sink_dependent) {
560 _dg.make_edge(s1, slice_sink);
561 }
562 }
563 #ifndef PRODUCT
564 if (TraceSuperWord) {
565 tty->print_cr("\nDependence graph for slice: %d", n->_idx);
566 for (int q = 0; q < _nlist.length(); q++) {
567 _dg.print(_nlist.at(q));
568 }
569 tty->cr();
570 }
571 #endif
572 _nlist.clear();
573 }
575 #ifndef PRODUCT
576 if (TraceSuperWord) {
577 tty->print_cr("\ndisjoint_ptrs: %s", _disjoint_ptrs.length() > 0 ? "" : "NONE");
578 for (int r = 0; r < _disjoint_ptrs.length(); r++) {
579 _disjoint_ptrs.at(r).print();
580 tty->cr();
581 }
582 tty->cr();
583 }
584 #endif
585 }
587 //---------------------------mem_slice_preds---------------------------
588 // Return a memory slice (node list) in predecessor order starting at "start"
589 void SuperWord::mem_slice_preds(Node* start, Node* stop, GrowableArray<Node*> &preds) {
590 assert(preds.length() == 0, "start empty");
591 Node* n = start;
592 Node* prev = NULL;
593 while (true) {
594 assert(in_bb(n), "must be in block");
595 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
596 Node* out = n->fast_out(i);
597 if (out->is_Load()) {
598 if (in_bb(out)) {
599 preds.push(out);
600 }
601 } else {
602 // FIXME
603 if (out->is_MergeMem() && !in_bb(out)) {
604 // Either unrolling is causing a memory edge not to disappear,
605 // or need to run igvn.optimize() again before SLP
606 } else if (out->is_Phi() && out->bottom_type() == Type::MEMORY && !in_bb(out)) {
607 // Ditto. Not sure what else to check further.
608 } else if (out->Opcode() == Op_StoreCM && out->in(MemNode::OopStore) == n) {
609 // StoreCM has an input edge used as a precedence edge.
610 // Maybe an issue when oop stores are vectorized.
611 } else {
612 assert(out == prev || prev == NULL, "no branches off of store slice");
613 }
614 }
615 }
616 if (n == stop) break;
617 preds.push(n);
618 prev = n;
619 assert(n->is_Mem(), err_msg_res("unexpected node %s", n->Name()));
620 n = n->in(MemNode::Memory);
621 }
622 }
624 //------------------------------stmts_can_pack---------------------------
625 // Can s1 and s2 be in a pack with s1 immediately preceding s2 and
626 // s1 aligned at "align"
627 bool SuperWord::stmts_can_pack(Node* s1, Node* s2, int align) {
629 // Do not use superword for non-primitives
630 BasicType bt1 = velt_basic_type(s1);
631 BasicType bt2 = velt_basic_type(s2);
632 if(!is_java_primitive(bt1) || !is_java_primitive(bt2))
633 return false;
634 if (Matcher::max_vector_size(bt1) < 2) {
635 return false; // No vectors for this type
636 }
638 if (isomorphic(s1, s2)) {
639 if (independent(s1, s2)) {
640 if (!exists_at(s1, 0) && !exists_at(s2, 1)) {
641 if (!s1->is_Mem() || are_adjacent_refs(s1, s2)) {
642 int s1_align = alignment(s1);
643 int s2_align = alignment(s2);
644 if (s1_align == top_align || s1_align == align) {
645 if (s2_align == top_align || s2_align == align + data_size(s1)) {
646 return true;
647 }
648 }
649 }
650 }
651 }
652 }
653 return false;
654 }
656 //------------------------------exists_at---------------------------
657 // Does s exist in a pack at position pos?
658 bool SuperWord::exists_at(Node* s, uint pos) {
659 for (int i = 0; i < _packset.length(); i++) {
660 Node_List* p = _packset.at(i);
661 if (p->at(pos) == s) {
662 return true;
663 }
664 }
665 return false;
666 }
668 //------------------------------are_adjacent_refs---------------------------
669 // Is s1 immediately before s2 in memory?
670 bool SuperWord::are_adjacent_refs(Node* s1, Node* s2) {
671 if (!s1->is_Mem() || !s2->is_Mem()) return false;
672 if (!in_bb(s1) || !in_bb(s2)) return false;
674 // Do not use superword for non-primitives
675 if (!is_java_primitive(s1->as_Mem()->memory_type()) ||
676 !is_java_primitive(s2->as_Mem()->memory_type())) {
677 return false;
678 }
680 // FIXME - co_locate_pack fails on Stores in different mem-slices, so
681 // only pack memops that are in the same alias set until that's fixed.
682 if (_phase->C->get_alias_index(s1->as_Mem()->adr_type()) !=
683 _phase->C->get_alias_index(s2->as_Mem()->adr_type()))
684 return false;
685 SWPointer p1(s1->as_Mem(), this);
686 SWPointer p2(s2->as_Mem(), this);
687 if (p1.base() != p2.base() || !p1.comparable(p2)) return false;
688 int diff = p2.offset_in_bytes() - p1.offset_in_bytes();
689 return diff == data_size(s1);
690 }
692 //------------------------------isomorphic---------------------------
693 // Are s1 and s2 similar?
694 bool SuperWord::isomorphic(Node* s1, Node* s2) {
695 if (s1->Opcode() != s2->Opcode()) return false;
696 if (s1->req() != s2->req()) return false;
697 if (s1->in(0) != s2->in(0)) return false;
698 if (!same_velt_type(s1, s2)) return false;
699 return true;
700 }
702 //------------------------------independent---------------------------
703 // Is there no data path from s1 to s2 or s2 to s1?
704 bool SuperWord::independent(Node* s1, Node* s2) {
705 // assert(s1->Opcode() == s2->Opcode(), "check isomorphic first");
706 int d1 = depth(s1);
707 int d2 = depth(s2);
708 if (d1 == d2) return s1 != s2;
709 Node* deep = d1 > d2 ? s1 : s2;
710 Node* shallow = d1 > d2 ? s2 : s1;
712 visited_clear();
714 return independent_path(shallow, deep);
715 }
717 //------------------------------independent_path------------------------------
718 // Helper for independent
719 bool SuperWord::independent_path(Node* shallow, Node* deep, uint dp) {
720 if (dp >= 1000) return false; // stop deep recursion
721 visited_set(deep);
722 int shal_depth = depth(shallow);
723 assert(shal_depth <= depth(deep), "must be");
724 for (DepPreds preds(deep, _dg); !preds.done(); preds.next()) {
725 Node* pred = preds.current();
726 if (in_bb(pred) && !visited_test(pred)) {
727 if (shallow == pred) {
728 return false;
729 }
730 if (shal_depth < depth(pred) && !independent_path(shallow, pred, dp+1)) {
731 return false;
732 }
733 }
734 }
735 return true;
736 }
738 //------------------------------set_alignment---------------------------
739 void SuperWord::set_alignment(Node* s1, Node* s2, int align) {
740 set_alignment(s1, align);
741 if (align == top_align || align == bottom_align) {
742 set_alignment(s2, align);
743 } else {
744 set_alignment(s2, align + data_size(s1));
745 }
746 }
748 //------------------------------data_size---------------------------
749 int SuperWord::data_size(Node* s) {
750 int bsize = type2aelembytes(velt_basic_type(s));
751 assert(bsize != 0, "valid size");
752 return bsize;
753 }
755 //------------------------------extend_packlist---------------------------
756 // Extend packset by following use->def and def->use links from pack members.
757 void SuperWord::extend_packlist() {
758 bool changed;
759 do {
760 changed = false;
761 for (int i = 0; i < _packset.length(); i++) {
762 Node_List* p = _packset.at(i);
763 changed |= follow_use_defs(p);
764 changed |= follow_def_uses(p);
765 }
766 } while (changed);
768 #ifndef PRODUCT
769 if (TraceSuperWord) {
770 tty->print_cr("\nAfter extend_packlist");
771 print_packset();
772 }
773 #endif
774 }
776 //------------------------------follow_use_defs---------------------------
777 // Extend the packset by visiting operand definitions of nodes in pack p
778 bool SuperWord::follow_use_defs(Node_List* p) {
779 assert(p->size() == 2, "just checking");
780 Node* s1 = p->at(0);
781 Node* s2 = p->at(1);
782 assert(s1->req() == s2->req(), "just checking");
783 assert(alignment(s1) + data_size(s1) == alignment(s2), "just checking");
785 if (s1->is_Load()) return false;
787 int align = alignment(s1);
788 bool changed = false;
789 int start = s1->is_Store() ? MemNode::ValueIn : 1;
790 int end = s1->is_Store() ? MemNode::ValueIn+1 : s1->req();
791 for (int j = start; j < end; j++) {
792 Node* t1 = s1->in(j);
793 Node* t2 = s2->in(j);
794 if (!in_bb(t1) || !in_bb(t2))
795 continue;
796 if (stmts_can_pack(t1, t2, align)) {
797 if (est_savings(t1, t2) >= 0) {
798 Node_List* pair = new Node_List();
799 pair->push(t1);
800 pair->push(t2);
801 _packset.append(pair);
802 set_alignment(t1, t2, align);
803 changed = true;
804 }
805 }
806 }
807 return changed;
808 }
810 //------------------------------follow_def_uses---------------------------
811 // Extend the packset by visiting uses of nodes in pack p
812 bool SuperWord::follow_def_uses(Node_List* p) {
813 bool changed = false;
814 Node* s1 = p->at(0);
815 Node* s2 = p->at(1);
816 assert(p->size() == 2, "just checking");
817 assert(s1->req() == s2->req(), "just checking");
818 assert(alignment(s1) + data_size(s1) == alignment(s2), "just checking");
820 if (s1->is_Store()) return false;
822 int align = alignment(s1);
823 int savings = -1;
824 Node* u1 = NULL;
825 Node* u2 = NULL;
826 for (DUIterator_Fast imax, i = s1->fast_outs(imax); i < imax; i++) {
827 Node* t1 = s1->fast_out(i);
828 if (!in_bb(t1)) continue;
829 for (DUIterator_Fast jmax, j = s2->fast_outs(jmax); j < jmax; j++) {
830 Node* t2 = s2->fast_out(j);
831 if (!in_bb(t2)) continue;
832 if (!opnd_positions_match(s1, t1, s2, t2))
833 continue;
834 if (stmts_can_pack(t1, t2, align)) {
835 int my_savings = est_savings(t1, t2);
836 if (my_savings > savings) {
837 savings = my_savings;
838 u1 = t1;
839 u2 = t2;
840 }
841 }
842 }
843 }
844 if (savings >= 0) {
845 Node_List* pair = new Node_List();
846 pair->push(u1);
847 pair->push(u2);
848 _packset.append(pair);
849 set_alignment(u1, u2, align);
850 changed = true;
851 }
852 return changed;
853 }
855 //---------------------------opnd_positions_match-------------------------
856 // Is the use of d1 in u1 at the same operand position as d2 in u2?
857 bool SuperWord::opnd_positions_match(Node* d1, Node* u1, Node* d2, Node* u2) {
858 uint ct = u1->req();
859 if (ct != u2->req()) return false;
860 uint i1 = 0;
861 uint i2 = 0;
862 do {
863 for (i1++; i1 < ct; i1++) if (u1->in(i1) == d1) break;
864 for (i2++; i2 < ct; i2++) if (u2->in(i2) == d2) break;
865 if (i1 != i2) {
866 if ((i1 == (3-i2)) && (u2->is_Add() || u2->is_Mul())) {
867 // Further analysis relies on operands position matching.
868 u2->swap_edges(i1, i2);
869 } else {
870 return false;
871 }
872 }
873 } while (i1 < ct);
874 return true;
875 }
877 //------------------------------est_savings---------------------------
878 // Estimate the savings from executing s1 and s2 as a pack
879 int SuperWord::est_savings(Node* s1, Node* s2) {
880 int save_in = 2 - 1; // 2 operations per instruction in packed form
882 // inputs
883 for (uint i = 1; i < s1->req(); i++) {
884 Node* x1 = s1->in(i);
885 Node* x2 = s2->in(i);
886 if (x1 != x2) {
887 if (are_adjacent_refs(x1, x2)) {
888 save_in += adjacent_profit(x1, x2);
889 } else if (!in_packset(x1, x2)) {
890 save_in -= pack_cost(2);
891 } else {
892 save_in += unpack_cost(2);
893 }
894 }
895 }
897 // uses of result
898 uint ct = 0;
899 int save_use = 0;
900 for (DUIterator_Fast imax, i = s1->fast_outs(imax); i < imax; i++) {
901 Node* s1_use = s1->fast_out(i);
902 for (int j = 0; j < _packset.length(); j++) {
903 Node_List* p = _packset.at(j);
904 if (p->at(0) == s1_use) {
905 for (DUIterator_Fast kmax, k = s2->fast_outs(kmax); k < kmax; k++) {
906 Node* s2_use = s2->fast_out(k);
907 if (p->at(p->size()-1) == s2_use) {
908 ct++;
909 if (are_adjacent_refs(s1_use, s2_use)) {
910 save_use += adjacent_profit(s1_use, s2_use);
911 }
912 }
913 }
914 }
915 }
916 }
918 if (ct < s1->outcnt()) save_use += unpack_cost(1);
919 if (ct < s2->outcnt()) save_use += unpack_cost(1);
921 return MAX2(save_in, save_use);
922 }
924 //------------------------------costs---------------------------
925 int SuperWord::adjacent_profit(Node* s1, Node* s2) { return 2; }
926 int SuperWord::pack_cost(int ct) { return ct; }
927 int SuperWord::unpack_cost(int ct) { return ct; }
929 //------------------------------combine_packs---------------------------
930 // Combine packs A and B with A.last == B.first into A.first..,A.last,B.second,..B.last
931 void SuperWord::combine_packs() {
932 bool changed = true;
933 // Combine packs regardless max vector size.
934 while (changed) {
935 changed = false;
936 for (int i = 0; i < _packset.length(); i++) {
937 Node_List* p1 = _packset.at(i);
938 if (p1 == NULL) continue;
939 for (int j = 0; j < _packset.length(); j++) {
940 Node_List* p2 = _packset.at(j);
941 if (p2 == NULL) continue;
942 if (i == j) continue;
943 if (p1->at(p1->size()-1) == p2->at(0)) {
944 for (uint k = 1; k < p2->size(); k++) {
945 p1->push(p2->at(k));
946 }
947 _packset.at_put(j, NULL);
948 changed = true;
949 }
950 }
951 }
952 }
954 // Split packs which have size greater then max vector size.
955 for (int i = 0; i < _packset.length(); i++) {
956 Node_List* p1 = _packset.at(i);
957 if (p1 != NULL) {
958 BasicType bt = velt_basic_type(p1->at(0));
959 uint max_vlen = Matcher::max_vector_size(bt); // Max elements in vector
960 assert(is_power_of_2(max_vlen), "sanity");
961 uint psize = p1->size();
962 if (!is_power_of_2(psize)) {
963 // Skip pack which can't be vector.
964 // case1: for(...) { a[i] = i; } elements values are different (i+x)
965 // case2: for(...) { a[i] = b[i+1]; } can't align both, load and store
966 _packset.at_put(i, NULL);
967 continue;
968 }
969 if (psize > max_vlen) {
970 Node_List* pack = new Node_List();
971 for (uint j = 0; j < psize; j++) {
972 pack->push(p1->at(j));
973 if (pack->size() >= max_vlen) {
974 assert(is_power_of_2(pack->size()), "sanity");
975 _packset.append(pack);
976 pack = new Node_List();
977 }
978 }
979 _packset.at_put(i, NULL);
980 }
981 }
982 }
984 // Compress list.
985 for (int i = _packset.length() - 1; i >= 0; i--) {
986 Node_List* p1 = _packset.at(i);
987 if (p1 == NULL) {
988 _packset.remove_at(i);
989 }
990 }
992 #ifndef PRODUCT
993 if (TraceSuperWord) {
994 tty->print_cr("\nAfter combine_packs");
995 print_packset();
996 }
997 #endif
998 }
1000 //-----------------------------construct_my_pack_map--------------------------
1001 // Construct the map from nodes to packs. Only valid after the
1002 // point where a node is only in one pack (after combine_packs).
1003 void SuperWord::construct_my_pack_map() {
1004 Node_List* rslt = NULL;
1005 for (int i = 0; i < _packset.length(); i++) {
1006 Node_List* p = _packset.at(i);
1007 for (uint j = 0; j < p->size(); j++) {
1008 Node* s = p->at(j);
1009 assert(my_pack(s) == NULL, "only in one pack");
1010 set_my_pack(s, p);
1011 }
1012 }
1013 }
1015 //------------------------------filter_packs---------------------------
1016 // Remove packs that are not implemented or not profitable.
1017 void SuperWord::filter_packs() {
1019 // Remove packs that are not implemented
1020 for (int i = _packset.length() - 1; i >= 0; i--) {
1021 Node_List* pk = _packset.at(i);
1022 bool impl = implemented(pk);
1023 if (!impl) {
1024 #ifndef PRODUCT
1025 if (TraceSuperWord && Verbose) {
1026 tty->print_cr("Unimplemented");
1027 pk->at(0)->dump();
1028 }
1029 #endif
1030 remove_pack_at(i);
1031 }
1032 }
1034 // Remove packs that are not profitable
1035 bool changed;
1036 do {
1037 changed = false;
1038 for (int i = _packset.length() - 1; i >= 0; i--) {
1039 Node_List* pk = _packset.at(i);
1040 bool prof = profitable(pk);
1041 if (!prof) {
1042 #ifndef PRODUCT
1043 if (TraceSuperWord && Verbose) {
1044 tty->print_cr("Unprofitable");
1045 pk->at(0)->dump();
1046 }
1047 #endif
1048 remove_pack_at(i);
1049 changed = true;
1050 }
1051 }
1052 } while (changed);
1054 #ifndef PRODUCT
1055 if (TraceSuperWord) {
1056 tty->print_cr("\nAfter filter_packs");
1057 print_packset();
1058 tty->cr();
1059 }
1060 #endif
1061 }
1063 //------------------------------implemented---------------------------
1064 // Can code be generated for pack p?
1065 bool SuperWord::implemented(Node_List* p) {
1066 Node* p0 = p->at(0);
1067 return VectorNode::implemented(p0->Opcode(), p->size(), velt_basic_type(p0));
1068 }
1070 //------------------------------same_inputs--------------------------
1071 // For pack p, are all idx operands the same?
1072 static bool same_inputs(Node_List* p, int idx) {
1073 Node* p0 = p->at(0);
1074 uint vlen = p->size();
1075 Node* p0_def = p0->in(idx);
1076 for (uint i = 1; i < vlen; i++) {
1077 Node* pi = p->at(i);
1078 Node* pi_def = pi->in(idx);
1079 if (p0_def != pi_def)
1080 return false;
1081 }
1082 return true;
1083 }
1085 //------------------------------profitable---------------------------
1086 // For pack p, are all operands and all uses (with in the block) vector?
1087 bool SuperWord::profitable(Node_List* p) {
1088 Node* p0 = p->at(0);
1089 uint start, end;
1090 VectorNode::vector_operands(p0, &start, &end);
1092 // Return false if some inputs are not vectors or vectors with different
1093 // size or alignment.
1094 // Also, for now, return false if not scalar promotion case when inputs are
1095 // the same. Later, implement PackNode and allow differing, non-vector inputs
1096 // (maybe just the ones from outside the block.)
1097 for (uint i = start; i < end; i++) {
1098 if (!is_vector_use(p0, i))
1099 return false;
1100 }
1101 if (VectorNode::is_shift(p0)) {
1102 // For now, return false if shift count is vector or not scalar promotion
1103 // case (different shift counts) because it is not supported yet.
1104 Node* cnt = p0->in(2);
1105 Node_List* cnt_pk = my_pack(cnt);
1106 if (cnt_pk != NULL)
1107 return false;
1108 if (!same_inputs(p, 2))
1109 return false;
1110 }
1111 if (!p0->is_Store()) {
1112 // For now, return false if not all uses are vector.
1113 // Later, implement ExtractNode and allow non-vector uses (maybe
1114 // just the ones outside the block.)
1115 for (uint i = 0; i < p->size(); i++) {
1116 Node* def = p->at(i);
1117 for (DUIterator_Fast jmax, j = def->fast_outs(jmax); j < jmax; j++) {
1118 Node* use = def->fast_out(j);
1119 for (uint k = 0; k < use->req(); k++) {
1120 Node* n = use->in(k);
1121 if (def == n) {
1122 if (!is_vector_use(use, k)) {
1123 return false;
1124 }
1125 }
1126 }
1127 }
1128 }
1129 }
1130 return true;
1131 }
1133 //------------------------------schedule---------------------------
1134 // Adjust the memory graph for the packed operations
1135 void SuperWord::schedule() {
1137 // Co-locate in the memory graph the members of each memory pack
1138 for (int i = 0; i < _packset.length(); i++) {
1139 co_locate_pack(_packset.at(i));
1140 }
1141 }
1143 //-------------------------------remove_and_insert-------------------
1144 // Remove "current" from its current position in the memory graph and insert
1145 // it after the appropriate insertion point (lip or uip).
1146 void SuperWord::remove_and_insert(MemNode *current, MemNode *prev, MemNode *lip,
1147 Node *uip, Unique_Node_List &sched_before) {
1148 Node* my_mem = current->in(MemNode::Memory);
1149 bool sched_up = sched_before.member(current);
1151 // remove current_store from its current position in the memmory graph
1152 for (DUIterator i = current->outs(); current->has_out(i); i++) {
1153 Node* use = current->out(i);
1154 if (use->is_Mem()) {
1155 assert(use->in(MemNode::Memory) == current, "must be");
1156 if (use == prev) { // connect prev to my_mem
1157 _igvn.replace_input_of(use, MemNode::Memory, my_mem);
1158 --i; //deleted this edge; rescan position
1159 } else if (sched_before.member(use)) {
1160 if (!sched_up) { // Will be moved together with current
1161 _igvn.replace_input_of(use, MemNode::Memory, uip);
1162 --i; //deleted this edge; rescan position
1163 }
1164 } else {
1165 if (sched_up) { // Will be moved together with current
1166 _igvn.replace_input_of(use, MemNode::Memory, lip);
1167 --i; //deleted this edge; rescan position
1168 }
1169 }
1170 }
1171 }
1173 Node *insert_pt = sched_up ? uip : lip;
1175 // all uses of insert_pt's memory state should use current's instead
1176 for (DUIterator i = insert_pt->outs(); insert_pt->has_out(i); i++) {
1177 Node* use = insert_pt->out(i);
1178 if (use->is_Mem()) {
1179 assert(use->in(MemNode::Memory) == insert_pt, "must be");
1180 _igvn.replace_input_of(use, MemNode::Memory, current);
1181 --i; //deleted this edge; rescan position
1182 } else if (!sched_up && use->is_Phi() && use->bottom_type() == Type::MEMORY) {
1183 uint pos; //lip (lower insert point) must be the last one in the memory slice
1184 for (pos=1; pos < use->req(); pos++) {
1185 if (use->in(pos) == insert_pt) break;
1186 }
1187 _igvn.replace_input_of(use, pos, current);
1188 --i;
1189 }
1190 }
1192 //connect current to insert_pt
1193 _igvn.replace_input_of(current, MemNode::Memory, insert_pt);
1194 }
1196 //------------------------------co_locate_pack----------------------------------
1197 // To schedule a store pack, we need to move any sandwiched memory ops either before
1198 // or after the pack, based upon dependence information:
1199 // (1) If any store in the pack depends on the sandwiched memory op, the
1200 // sandwiched memory op must be scheduled BEFORE the pack;
1201 // (2) If a sandwiched memory op depends on any store in the pack, the
1202 // sandwiched memory op must be scheduled AFTER the pack;
1203 // (3) If a sandwiched memory op (say, memA) depends on another sandwiched
1204 // memory op (say memB), memB must be scheduled before memA. So, if memA is
1205 // scheduled before the pack, memB must also be scheduled before the pack;
1206 // (4) If there is no dependence restriction for a sandwiched memory op, we simply
1207 // schedule this store AFTER the pack
1208 // (5) We know there is no dependence cycle, so there in no other case;
1209 // (6) Finally, all memory ops in another single pack should be moved in the same direction.
1210 //
1211 // To schedule a load pack, we use the memory state of either the first or the last load in
1212 // the pack, based on the dependence constraint.
1213 void SuperWord::co_locate_pack(Node_List* pk) {
1214 if (pk->at(0)->is_Store()) {
1215 MemNode* first = executed_first(pk)->as_Mem();
1216 MemNode* last = executed_last(pk)->as_Mem();
1217 Unique_Node_List schedule_before_pack;
1218 Unique_Node_List memops;
1220 MemNode* current = last->in(MemNode::Memory)->as_Mem();
1221 MemNode* previous = last;
1222 while (true) {
1223 assert(in_bb(current), "stay in block");
1224 memops.push(previous);
1225 for (DUIterator i = current->outs(); current->has_out(i); i++) {
1226 Node* use = current->out(i);
1227 if (use->is_Mem() && use != previous)
1228 memops.push(use);
1229 }
1230 if (current == first) break;
1231 previous = current;
1232 current = current->in(MemNode::Memory)->as_Mem();
1233 }
1235 // determine which memory operations should be scheduled before the pack
1236 for (uint i = 1; i < memops.size(); i++) {
1237 Node *s1 = memops.at(i);
1238 if (!in_pack(s1, pk) && !schedule_before_pack.member(s1)) {
1239 for (uint j = 0; j< i; j++) {
1240 Node *s2 = memops.at(j);
1241 if (!independent(s1, s2)) {
1242 if (in_pack(s2, pk) || schedule_before_pack.member(s2)) {
1243 schedule_before_pack.push(s1); // s1 must be scheduled before
1244 Node_List* mem_pk = my_pack(s1);
1245 if (mem_pk != NULL) {
1246 for (uint ii = 0; ii < mem_pk->size(); ii++) {
1247 Node* s = mem_pk->at(ii); // follow partner
1248 if (memops.member(s) && !schedule_before_pack.member(s))
1249 schedule_before_pack.push(s);
1250 }
1251 }
1252 break;
1253 }
1254 }
1255 }
1256 }
1257 }
1259 Node* upper_insert_pt = first->in(MemNode::Memory);
1260 // Following code moves loads connected to upper_insert_pt below aliased stores.
1261 // Collect such loads here and reconnect them back to upper_insert_pt later.
1262 memops.clear();
1263 for (DUIterator i = upper_insert_pt->outs(); upper_insert_pt->has_out(i); i++) {
1264 Node* use = upper_insert_pt->out(i);
1265 if (use->is_Mem() && !use->is_Store()) {
1266 memops.push(use);
1267 }
1268 }
1270 MemNode* lower_insert_pt = last;
1271 previous = last; //previous store in pk
1272 current = last->in(MemNode::Memory)->as_Mem();
1274 // start scheduling from "last" to "first"
1275 while (true) {
1276 assert(in_bb(current), "stay in block");
1277 assert(in_pack(previous, pk), "previous stays in pack");
1278 Node* my_mem = current->in(MemNode::Memory);
1280 if (in_pack(current, pk)) {
1281 // Forward users of my memory state (except "previous) to my input memory state
1282 for (DUIterator i = current->outs(); current->has_out(i); i++) {
1283 Node* use = current->out(i);
1284 if (use->is_Mem() && use != previous) {
1285 assert(use->in(MemNode::Memory) == current, "must be");
1286 if (schedule_before_pack.member(use)) {
1287 _igvn.replace_input_of(use, MemNode::Memory, upper_insert_pt);
1288 } else {
1289 _igvn.replace_input_of(use, MemNode::Memory, lower_insert_pt);
1290 }
1291 --i; // deleted this edge; rescan position
1292 }
1293 }
1294 previous = current;
1295 } else { // !in_pack(current, pk) ==> a sandwiched store
1296 remove_and_insert(current, previous, lower_insert_pt, upper_insert_pt, schedule_before_pack);
1297 }
1299 if (current == first) break;
1300 current = my_mem->as_Mem();
1301 } // end while
1303 // Reconnect loads back to upper_insert_pt.
1304 for (uint i = 0; i < memops.size(); i++) {
1305 Node *ld = memops.at(i);
1306 if (ld->in(MemNode::Memory) != upper_insert_pt) {
1307 _igvn.replace_input_of(ld, MemNode::Memory, upper_insert_pt);
1308 }
1309 }
1310 } else if (pk->at(0)->is_Load()) { //load
1311 // all loads in the pack should have the same memory state. By default,
1312 // we use the memory state of the last load. However, if any load could
1313 // not be moved down due to the dependence constraint, we use the memory
1314 // state of the first load.
1315 Node* last_mem = executed_last(pk)->in(MemNode::Memory);
1316 Node* first_mem = executed_first(pk)->in(MemNode::Memory);
1317 bool schedule_last = true;
1318 for (uint i = 0; i < pk->size(); i++) {
1319 Node* ld = pk->at(i);
1320 for (Node* current = last_mem; current != ld->in(MemNode::Memory);
1321 current=current->in(MemNode::Memory)) {
1322 assert(current != first_mem, "corrupted memory graph");
1323 if(current->is_Mem() && !independent(current, ld)){
1324 schedule_last = false; // a later store depends on this load
1325 break;
1326 }
1327 }
1328 }
1330 Node* mem_input = schedule_last ? last_mem : first_mem;
1331 _igvn.hash_delete(mem_input);
1332 // Give each load the same memory state
1333 for (uint i = 0; i < pk->size(); i++) {
1334 LoadNode* ld = pk->at(i)->as_Load();
1335 _igvn.replace_input_of(ld, MemNode::Memory, mem_input);
1336 }
1337 }
1338 }
1340 //------------------------------output---------------------------
1341 // Convert packs into vector node operations
1342 void SuperWord::output() {
1343 if (_packset.length() == 0) return;
1345 #ifndef PRODUCT
1346 if (TraceLoopOpts) {
1347 tty->print("SuperWord ");
1348 lpt()->dump_head();
1349 }
1350 #endif
1352 // MUST ENSURE main loop's initial value is properly aligned:
1353 // (iv_initial_value + min_iv_offset) % vector_width_in_bytes() == 0
1355 align_initial_loop_index(align_to_ref());
1357 // Insert extract (unpack) operations for scalar uses
1358 for (int i = 0; i < _packset.length(); i++) {
1359 insert_extracts(_packset.at(i));
1360 }
1362 Compile* C = _phase->C;
1363 uint max_vlen_in_bytes = 0;
1364 for (int i = 0; i < _block.length(); i++) {
1365 Node* n = _block.at(i);
1366 Node_List* p = my_pack(n);
1367 if (p && n == executed_last(p)) {
1368 uint vlen = p->size();
1369 uint vlen_in_bytes = 0;
1370 Node* vn = NULL;
1371 Node* low_adr = p->at(0);
1372 Node* first = executed_first(p);
1373 int opc = n->Opcode();
1374 if (n->is_Load()) {
1375 Node* ctl = n->in(MemNode::Control);
1376 Node* mem = first->in(MemNode::Memory);
1377 SWPointer p1(n->as_Mem(), this);
1378 // Identify the memory dependency for the new loadVector node by
1379 // walking up through memory chain.
1380 // This is done to give flexibility to the new loadVector node so that
1381 // it can move above independent storeVector nodes.
1382 while (mem->is_StoreVector()) {
1383 SWPointer p2(mem->as_Mem(), this);
1384 int cmp = p1.cmp(p2);
1385 if (SWPointer::not_equal(cmp) || !SWPointer::comparable(cmp)) {
1386 mem = mem->in(MemNode::Memory);
1387 } else {
1388 break; // dependent memory
1389 }
1390 }
1391 Node* adr = low_adr->in(MemNode::Address);
1392 const TypePtr* atyp = n->adr_type();
1393 vn = LoadVectorNode::make(C, opc, ctl, mem, adr, atyp, vlen, velt_basic_type(n));
1394 vlen_in_bytes = vn->as_LoadVector()->memory_size();
1395 } else if (n->is_Store()) {
1396 // Promote value to be stored to vector
1397 Node* val = vector_opd(p, MemNode::ValueIn);
1398 Node* ctl = n->in(MemNode::Control);
1399 Node* mem = first->in(MemNode::Memory);
1400 Node* adr = low_adr->in(MemNode::Address);
1401 const TypePtr* atyp = n->adr_type();
1402 vn = StoreVectorNode::make(C, opc, ctl, mem, adr, atyp, val, vlen);
1403 vlen_in_bytes = vn->as_StoreVector()->memory_size();
1404 } else if (n->req() == 3) {
1405 // Promote operands to vector
1406 Node* in1 = vector_opd(p, 1);
1407 Node* in2 = vector_opd(p, 2);
1408 if (VectorNode::is_invariant_vector(in1) && (n->is_Add() || n->is_Mul())) {
1409 // Move invariant vector input into second position to avoid register spilling.
1410 Node* tmp = in1;
1411 in1 = in2;
1412 in2 = tmp;
1413 }
1414 vn = VectorNode::make(C, opc, in1, in2, vlen, velt_basic_type(n));
1415 vlen_in_bytes = vn->as_Vector()->length_in_bytes();
1416 } else {
1417 ShouldNotReachHere();
1418 }
1419 assert(vn != NULL, "sanity");
1420 _igvn.register_new_node_with_optimizer(vn);
1421 _phase->set_ctrl(vn, _phase->get_ctrl(p->at(0)));
1422 for (uint j = 0; j < p->size(); j++) {
1423 Node* pm = p->at(j);
1424 _igvn.replace_node(pm, vn);
1425 }
1426 _igvn._worklist.push(vn);
1428 if (vlen_in_bytes > max_vlen_in_bytes) {
1429 max_vlen_in_bytes = vlen_in_bytes;
1430 }
1431 #ifdef ASSERT
1432 if (TraceNewVectors) {
1433 tty->print("new Vector node: ");
1434 vn->dump();
1435 }
1436 #endif
1437 }
1438 }
1439 C->set_max_vector_size(max_vlen_in_bytes);
1440 }
1442 //------------------------------vector_opd---------------------------
1443 // Create a vector operand for the nodes in pack p for operand: in(opd_idx)
1444 Node* SuperWord::vector_opd(Node_List* p, int opd_idx) {
1445 Node* p0 = p->at(0);
1446 uint vlen = p->size();
1447 Node* opd = p0->in(opd_idx);
1449 if (same_inputs(p, opd_idx)) {
1450 if (opd->is_Vector() || opd->is_LoadVector()) {
1451 assert(((opd_idx != 2) || !VectorNode::is_shift(p0)), "shift's count can't be vector");
1452 return opd; // input is matching vector
1453 }
1454 if ((opd_idx == 2) && VectorNode::is_shift(p0)) {
1455 Compile* C = _phase->C;
1456 Node* cnt = opd;
1457 // Vector instructions do not mask shift count, do it here.
1458 juint mask = (p0->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
1459 const TypeInt* t = opd->find_int_type();
1460 if (t != NULL && t->is_con()) {
1461 juint shift = t->get_con();
1462 if (shift > mask) { // Unsigned cmp
1463 cnt = ConNode::make(C, TypeInt::make(shift & mask));
1464 }
1465 } else {
1466 if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
1467 cnt = ConNode::make(C, TypeInt::make(mask));
1468 _igvn.register_new_node_with_optimizer(cnt);
1469 cnt = new (C) AndINode(opd, cnt);
1470 _igvn.register_new_node_with_optimizer(cnt);
1471 _phase->set_ctrl(cnt, _phase->get_ctrl(opd));
1472 }
1473 assert(opd->bottom_type()->isa_int(), "int type only");
1474 // Move non constant shift count into vector register.
1475 cnt = VectorNode::shift_count(C, p0, cnt, vlen, velt_basic_type(p0));
1476 }
1477 if (cnt != opd) {
1478 _igvn.register_new_node_with_optimizer(cnt);
1479 _phase->set_ctrl(cnt, _phase->get_ctrl(opd));
1480 }
1481 return cnt;
1482 }
1483 assert(!opd->is_StoreVector(), "such vector is not expected here");
1484 // Convert scalar input to vector with the same number of elements as
1485 // p0's vector. Use p0's type because size of operand's container in
1486 // vector should match p0's size regardless operand's size.
1487 const Type* p0_t = velt_type(p0);
1488 VectorNode* vn = VectorNode::scalar2vector(_phase->C, opd, vlen, p0_t);
1490 _igvn.register_new_node_with_optimizer(vn);
1491 _phase->set_ctrl(vn, _phase->get_ctrl(opd));
1492 #ifdef ASSERT
1493 if (TraceNewVectors) {
1494 tty->print("new Vector node: ");
1495 vn->dump();
1496 }
1497 #endif
1498 return vn;
1499 }
1501 // Insert pack operation
1502 BasicType bt = velt_basic_type(p0);
1503 PackNode* pk = PackNode::make(_phase->C, opd, vlen, bt);
1504 DEBUG_ONLY( const BasicType opd_bt = opd->bottom_type()->basic_type(); )
1506 for (uint i = 1; i < vlen; i++) {
1507 Node* pi = p->at(i);
1508 Node* in = pi->in(opd_idx);
1509 assert(my_pack(in) == NULL, "Should already have been unpacked");
1510 assert(opd_bt == in->bottom_type()->basic_type(), "all same type");
1511 pk->add_opd(in);
1512 }
1513 _igvn.register_new_node_with_optimizer(pk);
1514 _phase->set_ctrl(pk, _phase->get_ctrl(opd));
1515 #ifdef ASSERT
1516 if (TraceNewVectors) {
1517 tty->print("new Vector node: ");
1518 pk->dump();
1519 }
1520 #endif
1521 return pk;
1522 }
1524 //------------------------------insert_extracts---------------------------
1525 // If a use of pack p is not a vector use, then replace the
1526 // use with an extract operation.
1527 void SuperWord::insert_extracts(Node_List* p) {
1528 if (p->at(0)->is_Store()) return;
1529 assert(_n_idx_list.is_empty(), "empty (node,index) list");
1531 // Inspect each use of each pack member. For each use that is
1532 // not a vector use, replace the use with an extract operation.
1534 for (uint i = 0; i < p->size(); i++) {
1535 Node* def = p->at(i);
1536 for (DUIterator_Fast jmax, j = def->fast_outs(jmax); j < jmax; j++) {
1537 Node* use = def->fast_out(j);
1538 for (uint k = 0; k < use->req(); k++) {
1539 Node* n = use->in(k);
1540 if (def == n) {
1541 if (!is_vector_use(use, k)) {
1542 _n_idx_list.push(use, k);
1543 }
1544 }
1545 }
1546 }
1547 }
1549 while (_n_idx_list.is_nonempty()) {
1550 Node* use = _n_idx_list.node();
1551 int idx = _n_idx_list.index();
1552 _n_idx_list.pop();
1553 Node* def = use->in(idx);
1555 // Insert extract operation
1556 _igvn.hash_delete(def);
1557 int def_pos = alignment(def) / data_size(def);
1559 Node* ex = ExtractNode::make(_phase->C, def, def_pos, velt_basic_type(def));
1560 _igvn.register_new_node_with_optimizer(ex);
1561 _phase->set_ctrl(ex, _phase->get_ctrl(def));
1562 _igvn.replace_input_of(use, idx, ex);
1563 _igvn._worklist.push(def);
1565 bb_insert_after(ex, bb_idx(def));
1566 set_velt_type(ex, velt_type(def));
1567 }
1568 }
1570 //------------------------------is_vector_use---------------------------
1571 // Is use->in(u_idx) a vector use?
1572 bool SuperWord::is_vector_use(Node* use, int u_idx) {
1573 Node_List* u_pk = my_pack(use);
1574 if (u_pk == NULL) return false;
1575 Node* def = use->in(u_idx);
1576 Node_List* d_pk = my_pack(def);
1577 if (d_pk == NULL) {
1578 // check for scalar promotion
1579 Node* n = u_pk->at(0)->in(u_idx);
1580 for (uint i = 1; i < u_pk->size(); i++) {
1581 if (u_pk->at(i)->in(u_idx) != n) return false;
1582 }
1583 return true;
1584 }
1585 if (u_pk->size() != d_pk->size())
1586 return false;
1587 for (uint i = 0; i < u_pk->size(); i++) {
1588 Node* ui = u_pk->at(i);
1589 Node* di = d_pk->at(i);
1590 if (ui->in(u_idx) != di || alignment(ui) != alignment(di))
1591 return false;
1592 }
1593 return true;
1594 }
1596 //------------------------------construct_bb---------------------------
1597 // Construct reverse postorder list of block members
1598 bool SuperWord::construct_bb() {
1599 Node* entry = bb();
1601 assert(_stk.length() == 0, "stk is empty");
1602 assert(_block.length() == 0, "block is empty");
1603 assert(_data_entry.length() == 0, "data_entry is empty");
1604 assert(_mem_slice_head.length() == 0, "mem_slice_head is empty");
1605 assert(_mem_slice_tail.length() == 0, "mem_slice_tail is empty");
1607 // Find non-control nodes with no inputs from within block,
1608 // create a temporary map from node _idx to bb_idx for use
1609 // by the visited and post_visited sets,
1610 // and count number of nodes in block.
1611 int bb_ct = 0;
1612 for (uint i = 0; i < lpt()->_body.size(); i++ ) {
1613 Node *n = lpt()->_body.at(i);
1614 set_bb_idx(n, i); // Create a temporary map
1615 if (in_bb(n)) {
1616 if (n->is_LoadStore() || n->is_MergeMem() ||
1617 (n->is_Proj() && !n->as_Proj()->is_CFG())) {
1618 // Bailout if the loop has LoadStore, MergeMem or data Proj
1619 // nodes. Superword optimization does not work with them.
1620 return false;
1621 }
1622 bb_ct++;
1623 if (!n->is_CFG()) {
1624 bool found = false;
1625 for (uint j = 0; j < n->req(); j++) {
1626 Node* def = n->in(j);
1627 if (def && in_bb(def)) {
1628 found = true;
1629 break;
1630 }
1631 }
1632 if (!found) {
1633 assert(n != entry, "can't be entry");
1634 _data_entry.push(n);
1635 }
1636 }
1637 }
1638 }
1640 // Find memory slices (head and tail)
1641 for (DUIterator_Fast imax, i = lp()->fast_outs(imax); i < imax; i++) {
1642 Node *n = lp()->fast_out(i);
1643 if (in_bb(n) && (n->is_Phi() && n->bottom_type() == Type::MEMORY)) {
1644 Node* n_tail = n->in(LoopNode::LoopBackControl);
1645 if (n_tail != n->in(LoopNode::EntryControl)) {
1646 if (!n_tail->is_Mem()) {
1647 assert(n_tail->is_Mem(), err_msg_res("unexpected node for memory slice: %s", n_tail->Name()));
1648 return false; // Bailout
1649 }
1650 _mem_slice_head.push(n);
1651 _mem_slice_tail.push(n_tail);
1652 }
1653 }
1654 }
1656 // Create an RPO list of nodes in block
1658 visited_clear();
1659 post_visited_clear();
1661 // Push all non-control nodes with no inputs from within block, then control entry
1662 for (int j = 0; j < _data_entry.length(); j++) {
1663 Node* n = _data_entry.at(j);
1664 visited_set(n);
1665 _stk.push(n);
1666 }
1667 visited_set(entry);
1668 _stk.push(entry);
1670 // Do a depth first walk over out edges
1671 int rpo_idx = bb_ct - 1;
1672 int size;
1673 while ((size = _stk.length()) > 0) {
1674 Node* n = _stk.top(); // Leave node on stack
1675 if (!visited_test_set(n)) {
1676 // forward arc in graph
1677 } else if (!post_visited_test(n)) {
1678 // cross or back arc
1679 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1680 Node *use = n->fast_out(i);
1681 if (in_bb(use) && !visited_test(use) &&
1682 // Don't go around backedge
1683 (!use->is_Phi() || n == entry)) {
1684 _stk.push(use);
1685 }
1686 }
1687 if (_stk.length() == size) {
1688 // There were no additional uses, post visit node now
1689 _stk.pop(); // Remove node from stack
1690 assert(rpo_idx >= 0, "");
1691 _block.at_put_grow(rpo_idx, n);
1692 rpo_idx--;
1693 post_visited_set(n);
1694 assert(rpo_idx >= 0 || _stk.is_empty(), "");
1695 }
1696 } else {
1697 _stk.pop(); // Remove post-visited node from stack
1698 }
1699 }
1701 // Create real map of block indices for nodes
1702 for (int j = 0; j < _block.length(); j++) {
1703 Node* n = _block.at(j);
1704 set_bb_idx(n, j);
1705 }
1707 initialize_bb(); // Ensure extra info is allocated.
1709 #ifndef PRODUCT
1710 if (TraceSuperWord) {
1711 print_bb();
1712 tty->print_cr("\ndata entry nodes: %s", _data_entry.length() > 0 ? "" : "NONE");
1713 for (int m = 0; m < _data_entry.length(); m++) {
1714 tty->print("%3d ", m);
1715 _data_entry.at(m)->dump();
1716 }
1717 tty->print_cr("\nmemory slices: %s", _mem_slice_head.length() > 0 ? "" : "NONE");
1718 for (int m = 0; m < _mem_slice_head.length(); m++) {
1719 tty->print("%3d ", m); _mem_slice_head.at(m)->dump();
1720 tty->print(" "); _mem_slice_tail.at(m)->dump();
1721 }
1722 }
1723 #endif
1724 assert(rpo_idx == -1 && bb_ct == _block.length(), "all block members found");
1725 return (_mem_slice_head.length() > 0) || (_data_entry.length() > 0);
1726 }
1728 //------------------------------initialize_bb---------------------------
1729 // Initialize per node info
1730 void SuperWord::initialize_bb() {
1731 Node* last = _block.at(_block.length() - 1);
1732 grow_node_info(bb_idx(last));
1733 }
1735 //------------------------------bb_insert_after---------------------------
1736 // Insert n into block after pos
1737 void SuperWord::bb_insert_after(Node* n, int pos) {
1738 int n_pos = pos + 1;
1739 // Make room
1740 for (int i = _block.length() - 1; i >= n_pos; i--) {
1741 _block.at_put_grow(i+1, _block.at(i));
1742 }
1743 for (int j = _node_info.length() - 1; j >= n_pos; j--) {
1744 _node_info.at_put_grow(j+1, _node_info.at(j));
1745 }
1746 // Set value
1747 _block.at_put_grow(n_pos, n);
1748 _node_info.at_put_grow(n_pos, SWNodeInfo::initial);
1749 // Adjust map from node->_idx to _block index
1750 for (int i = n_pos; i < _block.length(); i++) {
1751 set_bb_idx(_block.at(i), i);
1752 }
1753 }
1755 //------------------------------compute_max_depth---------------------------
1756 // Compute max depth for expressions from beginning of block
1757 // Use to prune search paths during test for independence.
1758 void SuperWord::compute_max_depth() {
1759 int ct = 0;
1760 bool again;
1761 do {
1762 again = false;
1763 for (int i = 0; i < _block.length(); i++) {
1764 Node* n = _block.at(i);
1765 if (!n->is_Phi()) {
1766 int d_orig = depth(n);
1767 int d_in = 0;
1768 for (DepPreds preds(n, _dg); !preds.done(); preds.next()) {
1769 Node* pred = preds.current();
1770 if (in_bb(pred)) {
1771 d_in = MAX2(d_in, depth(pred));
1772 }
1773 }
1774 if (d_in + 1 != d_orig) {
1775 set_depth(n, d_in + 1);
1776 again = true;
1777 }
1778 }
1779 }
1780 ct++;
1781 } while (again);
1782 #ifndef PRODUCT
1783 if (TraceSuperWord && Verbose)
1784 tty->print_cr("compute_max_depth iterated: %d times", ct);
1785 #endif
1786 }
1788 //-------------------------compute_vector_element_type-----------------------
1789 // Compute necessary vector element type for expressions
1790 // This propagates backwards a narrower integer type when the
1791 // upper bits of the value are not needed.
1792 // Example: char a,b,c; a = b + c;
1793 // Normally the type of the add is integer, but for packed character
1794 // operations the type of the add needs to be char.
1795 void SuperWord::compute_vector_element_type() {
1796 #ifndef PRODUCT
1797 if (TraceSuperWord && Verbose)
1798 tty->print_cr("\ncompute_velt_type:");
1799 #endif
1801 // Initial type
1802 for (int i = 0; i < _block.length(); i++) {
1803 Node* n = _block.at(i);
1804 set_velt_type(n, container_type(n));
1805 }
1807 // Propagate integer narrowed type backwards through operations
1808 // that don't depend on higher order bits
1809 for (int i = _block.length() - 1; i >= 0; i--) {
1810 Node* n = _block.at(i);
1811 // Only integer types need be examined
1812 const Type* vtn = velt_type(n);
1813 if (vtn->basic_type() == T_INT) {
1814 uint start, end;
1815 VectorNode::vector_operands(n, &start, &end);
1817 for (uint j = start; j < end; j++) {
1818 Node* in = n->in(j);
1819 // Don't propagate through a memory
1820 if (!in->is_Mem() && in_bb(in) && velt_type(in)->basic_type() == T_INT &&
1821 data_size(n) < data_size(in)) {
1822 bool same_type = true;
1823 for (DUIterator_Fast kmax, k = in->fast_outs(kmax); k < kmax; k++) {
1824 Node *use = in->fast_out(k);
1825 if (!in_bb(use) || !same_velt_type(use, n)) {
1826 same_type = false;
1827 break;
1828 }
1829 }
1830 if (same_type) {
1831 // For right shifts of small integer types (bool, byte, char, short)
1832 // we need precise information about sign-ness. Only Load nodes have
1833 // this information because Store nodes are the same for signed and
1834 // unsigned values. And any arithmetic operation after a load may
1835 // expand a value to signed Int so such right shifts can't be used
1836 // because vector elements do not have upper bits of Int.
1837 const Type* vt = vtn;
1838 if (VectorNode::is_shift(in)) {
1839 Node* load = in->in(1);
1840 if (load->is_Load() && in_bb(load) && (velt_type(load)->basic_type() == T_INT)) {
1841 vt = velt_type(load);
1842 } else if (in->Opcode() != Op_LShiftI) {
1843 // Widen type to Int to avoid creation of right shift vector
1844 // (align + data_size(s1) check in stmts_can_pack() will fail).
1845 // Note, left shifts work regardless type.
1846 vt = TypeInt::INT;
1847 }
1848 }
1849 set_velt_type(in, vt);
1850 }
1851 }
1852 }
1853 }
1854 }
1855 #ifndef PRODUCT
1856 if (TraceSuperWord && Verbose) {
1857 for (int i = 0; i < _block.length(); i++) {
1858 Node* n = _block.at(i);
1859 velt_type(n)->dump();
1860 tty->print("\t");
1861 n->dump();
1862 }
1863 }
1864 #endif
1865 }
1867 //------------------------------memory_alignment---------------------------
1868 // Alignment within a vector memory reference
1869 int SuperWord::memory_alignment(MemNode* s, int iv_adjust) {
1870 SWPointer p(s, this);
1871 if (!p.valid()) {
1872 return bottom_align;
1873 }
1874 int vw = vector_width_in_bytes(s);
1875 if (vw < 2) {
1876 return bottom_align; // No vectors for this type
1877 }
1878 int offset = p.offset_in_bytes();
1879 offset += iv_adjust*p.memory_size();
1880 int off_rem = offset % vw;
1881 int off_mod = off_rem >= 0 ? off_rem : off_rem + vw;
1882 return off_mod;
1883 }
1885 //---------------------------container_type---------------------------
1886 // Smallest type containing range of values
1887 const Type* SuperWord::container_type(Node* n) {
1888 if (n->is_Mem()) {
1889 BasicType bt = n->as_Mem()->memory_type();
1890 if (n->is_Store() && (bt == T_CHAR)) {
1891 // Use T_SHORT type instead of T_CHAR for stored values because any
1892 // preceding arithmetic operation extends values to signed Int.
1893 bt = T_SHORT;
1894 }
1895 if (n->Opcode() == Op_LoadUB) {
1896 // Adjust type for unsigned byte loads, it is important for right shifts.
1897 // T_BOOLEAN is used because there is no basic type representing type
1898 // TypeInt::UBYTE. Use of T_BOOLEAN for vectors is fine because only
1899 // size (one byte) and sign is important.
1900 bt = T_BOOLEAN;
1901 }
1902 return Type::get_const_basic_type(bt);
1903 }
1904 const Type* t = _igvn.type(n);
1905 if (t->basic_type() == T_INT) {
1906 // A narrow type of arithmetic operations will be determined by
1907 // propagating the type of memory operations.
1908 return TypeInt::INT;
1909 }
1910 return t;
1911 }
1913 bool SuperWord::same_velt_type(Node* n1, Node* n2) {
1914 const Type* vt1 = velt_type(n1);
1915 const Type* vt2 = velt_type(n2);
1916 if (vt1->basic_type() == T_INT && vt2->basic_type() == T_INT) {
1917 // Compare vectors element sizes for integer types.
1918 return data_size(n1) == data_size(n2);
1919 }
1920 return vt1 == vt2;
1921 }
1923 //------------------------------in_packset---------------------------
1924 // Are s1 and s2 in a pack pair and ordered as s1,s2?
1925 bool SuperWord::in_packset(Node* s1, Node* s2) {
1926 for (int i = 0; i < _packset.length(); i++) {
1927 Node_List* p = _packset.at(i);
1928 assert(p->size() == 2, "must be");
1929 if (p->at(0) == s1 && p->at(p->size()-1) == s2) {
1930 return true;
1931 }
1932 }
1933 return false;
1934 }
1936 //------------------------------in_pack---------------------------
1937 // Is s in pack p?
1938 Node_List* SuperWord::in_pack(Node* s, Node_List* p) {
1939 for (uint i = 0; i < p->size(); i++) {
1940 if (p->at(i) == s) {
1941 return p;
1942 }
1943 }
1944 return NULL;
1945 }
1947 //------------------------------remove_pack_at---------------------------
1948 // Remove the pack at position pos in the packset
1949 void SuperWord::remove_pack_at(int pos) {
1950 Node_List* p = _packset.at(pos);
1951 for (uint i = 0; i < p->size(); i++) {
1952 Node* s = p->at(i);
1953 set_my_pack(s, NULL);
1954 }
1955 _packset.remove_at(pos);
1956 }
1958 //------------------------------executed_first---------------------------
1959 // Return the node executed first in pack p. Uses the RPO block list
1960 // to determine order.
1961 Node* SuperWord::executed_first(Node_List* p) {
1962 Node* n = p->at(0);
1963 int n_rpo = bb_idx(n);
1964 for (uint i = 1; i < p->size(); i++) {
1965 Node* s = p->at(i);
1966 int s_rpo = bb_idx(s);
1967 if (s_rpo < n_rpo) {
1968 n = s;
1969 n_rpo = s_rpo;
1970 }
1971 }
1972 return n;
1973 }
1975 //------------------------------executed_last---------------------------
1976 // Return the node executed last in pack p.
1977 Node* SuperWord::executed_last(Node_List* p) {
1978 Node* n = p->at(0);
1979 int n_rpo = bb_idx(n);
1980 for (uint i = 1; i < p->size(); i++) {
1981 Node* s = p->at(i);
1982 int s_rpo = bb_idx(s);
1983 if (s_rpo > n_rpo) {
1984 n = s;
1985 n_rpo = s_rpo;
1986 }
1987 }
1988 return n;
1989 }
1991 //----------------------------align_initial_loop_index---------------------------
1992 // Adjust pre-loop limit so that in main loop, a load/store reference
1993 // to align_to_ref will be a position zero in the vector.
1994 // (iv + k) mod vector_align == 0
1995 void SuperWord::align_initial_loop_index(MemNode* align_to_ref) {
1996 CountedLoopNode *main_head = lp()->as_CountedLoop();
1997 assert(main_head->is_main_loop(), "");
1998 CountedLoopEndNode* pre_end = get_pre_loop_end(main_head);
1999 assert(pre_end != NULL, "");
2000 Node *pre_opaq1 = pre_end->limit();
2001 assert(pre_opaq1->Opcode() == Op_Opaque1, "");
2002 Opaque1Node *pre_opaq = (Opaque1Node*)pre_opaq1;
2003 Node *lim0 = pre_opaq->in(1);
2005 // Where we put new limit calculations
2006 Node *pre_ctrl = pre_end->loopnode()->in(LoopNode::EntryControl);
2008 // Ensure the original loop limit is available from the
2009 // pre-loop Opaque1 node.
2010 Node *orig_limit = pre_opaq->original_loop_limit();
2011 assert(orig_limit != NULL && _igvn.type(orig_limit) != Type::TOP, "");
2013 SWPointer align_to_ref_p(align_to_ref, this);
2014 assert(align_to_ref_p.valid(), "sanity");
2016 // Given:
2017 // lim0 == original pre loop limit
2018 // V == v_align (power of 2)
2019 // invar == extra invariant piece of the address expression
2020 // e == offset [ +/- invar ]
2021 //
2022 // When reassociating expressions involving '%' the basic rules are:
2023 // (a - b) % k == 0 => a % k == b % k
2024 // and:
2025 // (a + b) % k == 0 => a % k == (k - b) % k
2026 //
2027 // For stride > 0 && scale > 0,
2028 // Derive the new pre-loop limit "lim" such that the two constraints:
2029 // (1) lim = lim0 + N (where N is some positive integer < V)
2030 // (2) (e + lim) % V == 0
2031 // are true.
2032 //
2033 // Substituting (1) into (2),
2034 // (e + lim0 + N) % V == 0
2035 // solve for N:
2036 // N = (V - (e + lim0)) % V
2037 // substitute back into (1), so that new limit
2038 // lim = lim0 + (V - (e + lim0)) % V
2039 //
2040 // For stride > 0 && scale < 0
2041 // Constraints:
2042 // lim = lim0 + N
2043 // (e - lim) % V == 0
2044 // Solving for lim:
2045 // (e - lim0 - N) % V == 0
2046 // N = (e - lim0) % V
2047 // lim = lim0 + (e - lim0) % V
2048 //
2049 // For stride < 0 && scale > 0
2050 // Constraints:
2051 // lim = lim0 - N
2052 // (e + lim) % V == 0
2053 // Solving for lim:
2054 // (e + lim0 - N) % V == 0
2055 // N = (e + lim0) % V
2056 // lim = lim0 - (e + lim0) % V
2057 //
2058 // For stride < 0 && scale < 0
2059 // Constraints:
2060 // lim = lim0 - N
2061 // (e - lim) % V == 0
2062 // Solving for lim:
2063 // (e - lim0 + N) % V == 0
2064 // N = (V - (e - lim0)) % V
2065 // lim = lim0 - (V - (e - lim0)) % V
2067 int vw = vector_width_in_bytes(align_to_ref);
2068 int stride = iv_stride();
2069 int scale = align_to_ref_p.scale_in_bytes();
2070 int elt_size = align_to_ref_p.memory_size();
2071 int v_align = vw / elt_size;
2072 assert(v_align > 1, "sanity");
2073 int offset = align_to_ref_p.offset_in_bytes() / elt_size;
2074 Node *offsn = _igvn.intcon(offset);
2076 Node *e = offsn;
2077 if (align_to_ref_p.invar() != NULL) {
2078 // incorporate any extra invariant piece producing (offset +/- invar) >>> log2(elt)
2079 Node* log2_elt = _igvn.intcon(exact_log2(elt_size));
2080 Node* aref = new (_phase->C) URShiftINode(align_to_ref_p.invar(), log2_elt);
2081 _igvn.register_new_node_with_optimizer(aref);
2082 _phase->set_ctrl(aref, pre_ctrl);
2083 if (align_to_ref_p.negate_invar()) {
2084 e = new (_phase->C) SubINode(e, aref);
2085 } else {
2086 e = new (_phase->C) AddINode(e, aref);
2087 }
2088 _igvn.register_new_node_with_optimizer(e);
2089 _phase->set_ctrl(e, pre_ctrl);
2090 }
2091 if (vw > ObjectAlignmentInBytes) {
2092 // incorporate base e +/- base && Mask >>> log2(elt)
2093 Node* xbase = new(_phase->C) CastP2XNode(NULL, align_to_ref_p.base());
2094 _igvn.register_new_node_with_optimizer(xbase);
2095 #ifdef _LP64
2096 xbase = new (_phase->C) ConvL2INode(xbase);
2097 _igvn.register_new_node_with_optimizer(xbase);
2098 #endif
2099 Node* mask = _igvn.intcon(vw-1);
2100 Node* masked_xbase = new (_phase->C) AndINode(xbase, mask);
2101 _igvn.register_new_node_with_optimizer(masked_xbase);
2102 Node* log2_elt = _igvn.intcon(exact_log2(elt_size));
2103 Node* bref = new (_phase->C) URShiftINode(masked_xbase, log2_elt);
2104 _igvn.register_new_node_with_optimizer(bref);
2105 _phase->set_ctrl(bref, pre_ctrl);
2106 e = new (_phase->C) AddINode(e, bref);
2107 _igvn.register_new_node_with_optimizer(e);
2108 _phase->set_ctrl(e, pre_ctrl);
2109 }
2111 // compute e +/- lim0
2112 if (scale < 0) {
2113 e = new (_phase->C) SubINode(e, lim0);
2114 } else {
2115 e = new (_phase->C) AddINode(e, lim0);
2116 }
2117 _igvn.register_new_node_with_optimizer(e);
2118 _phase->set_ctrl(e, pre_ctrl);
2120 if (stride * scale > 0) {
2121 // compute V - (e +/- lim0)
2122 Node* va = _igvn.intcon(v_align);
2123 e = new (_phase->C) SubINode(va, e);
2124 _igvn.register_new_node_with_optimizer(e);
2125 _phase->set_ctrl(e, pre_ctrl);
2126 }
2127 // compute N = (exp) % V
2128 Node* va_msk = _igvn.intcon(v_align - 1);
2129 Node* N = new (_phase->C) AndINode(e, va_msk);
2130 _igvn.register_new_node_with_optimizer(N);
2131 _phase->set_ctrl(N, pre_ctrl);
2133 // substitute back into (1), so that new limit
2134 // lim = lim0 + N
2135 Node* lim;
2136 if (stride < 0) {
2137 lim = new (_phase->C) SubINode(lim0, N);
2138 } else {
2139 lim = new (_phase->C) AddINode(lim0, N);
2140 }
2141 _igvn.register_new_node_with_optimizer(lim);
2142 _phase->set_ctrl(lim, pre_ctrl);
2143 Node* constrained =
2144 (stride > 0) ? (Node*) new (_phase->C) MinINode(lim, orig_limit)
2145 : (Node*) new (_phase->C) MaxINode(lim, orig_limit);
2146 _igvn.register_new_node_with_optimizer(constrained);
2147 _phase->set_ctrl(constrained, pre_ctrl);
2148 _igvn.hash_delete(pre_opaq);
2149 pre_opaq->set_req(1, constrained);
2150 }
2152 //----------------------------get_pre_loop_end---------------------------
2153 // Find pre loop end from main loop. Returns null if none.
2154 CountedLoopEndNode* SuperWord::get_pre_loop_end(CountedLoopNode *cl) {
2155 Node *ctrl = cl->in(LoopNode::EntryControl);
2156 if (!ctrl->is_IfTrue() && !ctrl->is_IfFalse()) return NULL;
2157 Node *iffm = ctrl->in(0);
2158 if (!iffm->is_If()) return NULL;
2159 Node *p_f = iffm->in(0);
2160 if (!p_f->is_IfFalse()) return NULL;
2161 if (!p_f->in(0)->is_CountedLoopEnd()) return NULL;
2162 CountedLoopEndNode *pre_end = p_f->in(0)->as_CountedLoopEnd();
2163 if (!pre_end->loopnode()->is_pre_loop()) return NULL;
2164 return pre_end;
2165 }
2168 //------------------------------init---------------------------
2169 void SuperWord::init() {
2170 _dg.init();
2171 _packset.clear();
2172 _disjoint_ptrs.clear();
2173 _block.clear();
2174 _data_entry.clear();
2175 _mem_slice_head.clear();
2176 _mem_slice_tail.clear();
2177 _node_info.clear();
2178 _align_to_ref = NULL;
2179 _lpt = NULL;
2180 _lp = NULL;
2181 _bb = NULL;
2182 _iv = NULL;
2183 }
2185 //------------------------------print_packset---------------------------
2186 void SuperWord::print_packset() {
2187 #ifndef PRODUCT
2188 tty->print_cr("packset");
2189 for (int i = 0; i < _packset.length(); i++) {
2190 tty->print_cr("Pack: %d", i);
2191 Node_List* p = _packset.at(i);
2192 print_pack(p);
2193 }
2194 #endif
2195 }
2197 //------------------------------print_pack---------------------------
2198 void SuperWord::print_pack(Node_List* p) {
2199 for (uint i = 0; i < p->size(); i++) {
2200 print_stmt(p->at(i));
2201 }
2202 }
2204 //------------------------------print_bb---------------------------
2205 void SuperWord::print_bb() {
2206 #ifndef PRODUCT
2207 tty->print_cr("\nBlock");
2208 for (int i = 0; i < _block.length(); i++) {
2209 Node* n = _block.at(i);
2210 tty->print("%d ", i);
2211 if (n) {
2212 n->dump();
2213 }
2214 }
2215 #endif
2216 }
2218 //------------------------------print_stmt---------------------------
2219 void SuperWord::print_stmt(Node* s) {
2220 #ifndef PRODUCT
2221 tty->print(" align: %d \t", alignment(s));
2222 s->dump();
2223 #endif
2224 }
2226 //------------------------------blank---------------------------
2227 char* SuperWord::blank(uint depth) {
2228 static char blanks[101];
2229 assert(depth < 101, "too deep");
2230 for (uint i = 0; i < depth; i++) blanks[i] = ' ';
2231 blanks[depth] = '\0';
2232 return blanks;
2233 }
2236 //==============================SWPointer===========================
2238 //----------------------------SWPointer------------------------
2239 SWPointer::SWPointer(MemNode* mem, SuperWord* slp) :
2240 _mem(mem), _slp(slp), _base(NULL), _adr(NULL),
2241 _scale(0), _offset(0), _invar(NULL), _negate_invar(false) {
2243 Node* adr = mem->in(MemNode::Address);
2244 if (!adr->is_AddP()) {
2245 assert(!valid(), "too complex");
2246 return;
2247 }
2248 // Match AddP(base, AddP(ptr, k*iv [+ invariant]), constant)
2249 Node* base = adr->in(AddPNode::Base);
2250 //unsafe reference could not be aligned appropriately without runtime checking
2251 if (base == NULL || base->bottom_type() == Type::TOP) {
2252 assert(!valid(), "unsafe access");
2253 return;
2254 }
2255 for (int i = 0; i < 3; i++) {
2256 if (!scaled_iv_plus_offset(adr->in(AddPNode::Offset))) {
2257 assert(!valid(), "too complex");
2258 return;
2259 }
2260 adr = adr->in(AddPNode::Address);
2261 if (base == adr || !adr->is_AddP()) {
2262 break; // stop looking at addp's
2263 }
2264 }
2265 _base = base;
2266 _adr = adr;
2267 assert(valid(), "Usable");
2268 }
2270 // Following is used to create a temporary object during
2271 // the pattern match of an address expression.
2272 SWPointer::SWPointer(SWPointer* p) :
2273 _mem(p->_mem), _slp(p->_slp), _base(NULL), _adr(NULL),
2274 _scale(0), _offset(0), _invar(NULL), _negate_invar(false) {}
2276 //------------------------scaled_iv_plus_offset--------------------
2277 // Match: k*iv + offset
2278 // where: k is a constant that maybe zero, and
2279 // offset is (k2 [+/- invariant]) where k2 maybe zero and invariant is optional
2280 bool SWPointer::scaled_iv_plus_offset(Node* n) {
2281 if (scaled_iv(n)) {
2282 return true;
2283 }
2284 if (offset_plus_k(n)) {
2285 return true;
2286 }
2287 int opc = n->Opcode();
2288 if (opc == Op_AddI) {
2289 if (scaled_iv(n->in(1)) && offset_plus_k(n->in(2))) {
2290 return true;
2291 }
2292 if (scaled_iv(n->in(2)) && offset_plus_k(n->in(1))) {
2293 return true;
2294 }
2295 } else if (opc == Op_SubI) {
2296 if (scaled_iv(n->in(1)) && offset_plus_k(n->in(2), true)) {
2297 return true;
2298 }
2299 if (scaled_iv(n->in(2)) && offset_plus_k(n->in(1))) {
2300 _scale *= -1;
2301 return true;
2302 }
2303 }
2304 return false;
2305 }
2307 //----------------------------scaled_iv------------------------
2308 // Match: k*iv where k is a constant that's not zero
2309 bool SWPointer::scaled_iv(Node* n) {
2310 if (_scale != 0) {
2311 return false; // already found a scale
2312 }
2313 if (n == iv()) {
2314 _scale = 1;
2315 return true;
2316 }
2317 int opc = n->Opcode();
2318 if (opc == Op_MulI) {
2319 if (n->in(1) == iv() && n->in(2)->is_Con()) {
2320 _scale = n->in(2)->get_int();
2321 return true;
2322 } else if (n->in(2) == iv() && n->in(1)->is_Con()) {
2323 _scale = n->in(1)->get_int();
2324 return true;
2325 }
2326 } else if (opc == Op_LShiftI) {
2327 if (n->in(1) == iv() && n->in(2)->is_Con()) {
2328 _scale = 1 << n->in(2)->get_int();
2329 return true;
2330 }
2331 } else if (opc == Op_ConvI2L) {
2332 if (scaled_iv_plus_offset(n->in(1))) {
2333 return true;
2334 }
2335 } else if (opc == Op_LShiftL) {
2336 if (!has_iv() && _invar == NULL) {
2337 // Need to preserve the current _offset value, so
2338 // create a temporary object for this expression subtree.
2339 // Hacky, so should re-engineer the address pattern match.
2340 SWPointer tmp(this);
2341 if (tmp.scaled_iv_plus_offset(n->in(1))) {
2342 if (tmp._invar == NULL) {
2343 int mult = 1 << n->in(2)->get_int();
2344 _scale = tmp._scale * mult;
2345 _offset += tmp._offset * mult;
2346 return true;
2347 }
2348 }
2349 }
2350 }
2351 return false;
2352 }
2354 //----------------------------offset_plus_k------------------------
2355 // Match: offset is (k [+/- invariant])
2356 // where k maybe zero and invariant is optional, but not both.
2357 bool SWPointer::offset_plus_k(Node* n, bool negate) {
2358 int opc = n->Opcode();
2359 if (opc == Op_ConI) {
2360 _offset += negate ? -(n->get_int()) : n->get_int();
2361 return true;
2362 } else if (opc == Op_ConL) {
2363 // Okay if value fits into an int
2364 const TypeLong* t = n->find_long_type();
2365 if (t->higher_equal(TypeLong::INT)) {
2366 jlong loff = n->get_long();
2367 jint off = (jint)loff;
2368 _offset += negate ? -off : loff;
2369 return true;
2370 }
2371 return false;
2372 }
2373 if (_invar != NULL) return false; // already have an invariant
2374 if (opc == Op_AddI) {
2375 if (n->in(2)->is_Con() && invariant(n->in(1))) {
2376 _negate_invar = negate;
2377 _invar = n->in(1);
2378 _offset += negate ? -(n->in(2)->get_int()) : n->in(2)->get_int();
2379 return true;
2380 } else if (n->in(1)->is_Con() && invariant(n->in(2))) {
2381 _offset += negate ? -(n->in(1)->get_int()) : n->in(1)->get_int();
2382 _negate_invar = negate;
2383 _invar = n->in(2);
2384 return true;
2385 }
2386 }
2387 if (opc == Op_SubI) {
2388 if (n->in(2)->is_Con() && invariant(n->in(1))) {
2389 _negate_invar = negate;
2390 _invar = n->in(1);
2391 _offset += !negate ? -(n->in(2)->get_int()) : n->in(2)->get_int();
2392 return true;
2393 } else if (n->in(1)->is_Con() && invariant(n->in(2))) {
2394 _offset += negate ? -(n->in(1)->get_int()) : n->in(1)->get_int();
2395 _negate_invar = !negate;
2396 _invar = n->in(2);
2397 return true;
2398 }
2399 }
2400 if (invariant(n)) {
2401 _negate_invar = negate;
2402 _invar = n;
2403 return true;
2404 }
2405 return false;
2406 }
2408 //----------------------------print------------------------
2409 void SWPointer::print() {
2410 #ifndef PRODUCT
2411 tty->print("base: %d adr: %d scale: %d offset: %d invar: %c%d\n",
2412 _base != NULL ? _base->_idx : 0,
2413 _adr != NULL ? _adr->_idx : 0,
2414 _scale, _offset,
2415 _negate_invar?'-':'+',
2416 _invar != NULL ? _invar->_idx : 0);
2417 #endif
2418 }
2420 // ========================= OrderedPair =====================
2422 const OrderedPair OrderedPair::initial;
2424 // ========================= SWNodeInfo =====================
2426 const SWNodeInfo SWNodeInfo::initial;
2429 // ============================ DepGraph ===========================
2431 //------------------------------make_node---------------------------
2432 // Make a new dependence graph node for an ideal node.
2433 DepMem* DepGraph::make_node(Node* node) {
2434 DepMem* m = new (_arena) DepMem(node);
2435 if (node != NULL) {
2436 assert(_map.at_grow(node->_idx) == NULL, "one init only");
2437 _map.at_put_grow(node->_idx, m);
2438 }
2439 return m;
2440 }
2442 //------------------------------make_edge---------------------------
2443 // Make a new dependence graph edge from dpred -> dsucc
2444 DepEdge* DepGraph::make_edge(DepMem* dpred, DepMem* dsucc) {
2445 DepEdge* e = new (_arena) DepEdge(dpred, dsucc, dsucc->in_head(), dpred->out_head());
2446 dpred->set_out_head(e);
2447 dsucc->set_in_head(e);
2448 return e;
2449 }
2451 // ========================== DepMem ========================
2453 //------------------------------in_cnt---------------------------
2454 int DepMem::in_cnt() {
2455 int ct = 0;
2456 for (DepEdge* e = _in_head; e != NULL; e = e->next_in()) ct++;
2457 return ct;
2458 }
2460 //------------------------------out_cnt---------------------------
2461 int DepMem::out_cnt() {
2462 int ct = 0;
2463 for (DepEdge* e = _out_head; e != NULL; e = e->next_out()) ct++;
2464 return ct;
2465 }
2467 //------------------------------print-----------------------------
2468 void DepMem::print() {
2469 #ifndef PRODUCT
2470 tty->print(" DepNode %d (", _node->_idx);
2471 for (DepEdge* p = _in_head; p != NULL; p = p->next_in()) {
2472 Node* pred = p->pred()->node();
2473 tty->print(" %d", pred != NULL ? pred->_idx : 0);
2474 }
2475 tty->print(") [");
2476 for (DepEdge* s = _out_head; s != NULL; s = s->next_out()) {
2477 Node* succ = s->succ()->node();
2478 tty->print(" %d", succ != NULL ? succ->_idx : 0);
2479 }
2480 tty->print_cr(" ]");
2481 #endif
2482 }
2484 // =========================== DepEdge =========================
2486 //------------------------------DepPreds---------------------------
2487 void DepEdge::print() {
2488 #ifndef PRODUCT
2489 tty->print_cr("DepEdge: %d [ %d ]", _pred->node()->_idx, _succ->node()->_idx);
2490 #endif
2491 }
2493 // =========================== DepPreds =========================
2494 // Iterator over predecessor edges in the dependence graph.
2496 //------------------------------DepPreds---------------------------
2497 DepPreds::DepPreds(Node* n, DepGraph& dg) {
2498 _n = n;
2499 _done = false;
2500 if (_n->is_Store() || _n->is_Load()) {
2501 _next_idx = MemNode::Address;
2502 _end_idx = n->req();
2503 _dep_next = dg.dep(_n)->in_head();
2504 } else if (_n->is_Mem()) {
2505 _next_idx = 0;
2506 _end_idx = 0;
2507 _dep_next = dg.dep(_n)->in_head();
2508 } else {
2509 _next_idx = 1;
2510 _end_idx = _n->req();
2511 _dep_next = NULL;
2512 }
2513 next();
2514 }
2516 //------------------------------next---------------------------
2517 void DepPreds::next() {
2518 if (_dep_next != NULL) {
2519 _current = _dep_next->pred()->node();
2520 _dep_next = _dep_next->next_in();
2521 } else if (_next_idx < _end_idx) {
2522 _current = _n->in(_next_idx++);
2523 } else {
2524 _done = true;
2525 }
2526 }
2528 // =========================== DepSuccs =========================
2529 // Iterator over successor edges in the dependence graph.
2531 //------------------------------DepSuccs---------------------------
2532 DepSuccs::DepSuccs(Node* n, DepGraph& dg) {
2533 _n = n;
2534 _done = false;
2535 if (_n->is_Load()) {
2536 _next_idx = 0;
2537 _end_idx = _n->outcnt();
2538 _dep_next = dg.dep(_n)->out_head();
2539 } else if (_n->is_Mem() || _n->is_Phi() && _n->bottom_type() == Type::MEMORY) {
2540 _next_idx = 0;
2541 _end_idx = 0;
2542 _dep_next = dg.dep(_n)->out_head();
2543 } else {
2544 _next_idx = 0;
2545 _end_idx = _n->outcnt();
2546 _dep_next = NULL;
2547 }
2548 next();
2549 }
2551 //-------------------------------next---------------------------
2552 void DepSuccs::next() {
2553 if (_dep_next != NULL) {
2554 _current = _dep_next->succ()->node();
2555 _dep_next = _dep_next->next_out();
2556 } else if (_next_idx < _end_idx) {
2557 _current = _n->raw_out(_next_idx++);
2558 } else {
2559 _done = true;
2560 }
2561 }