1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2024, 2025, Alibaba Group Holding Limited. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "gc/shared/barrierSet.hpp"
27 #include "gc/shared/c2/barrierSetC2.hpp"
28 #include "libadt/vectset.hpp"
29 #include "memory/allocation.inline.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "opto/ad.hpp"
32 #include "opto/callGenerator.hpp"
33 #include "opto/castnode.hpp"
34 #include "opto/cfgnode.hpp"
35 #include "opto/connode.hpp"
36 #include "opto/loopnode.hpp"
37 #include "opto/machnode.hpp"
38 #include "opto/matcher.hpp"
39 #include "opto/node.hpp"
40 #include "opto/opcodes.hpp"
41 #include "opto/regmask.hpp"
42 #include "opto/rootnode.hpp"
43 #include "opto/type.hpp"
44 #include "utilities/copy.hpp"
45 #include "utilities/macros.hpp"
46 #include "utilities/powerOfTwo.hpp"
47 #include "utilities/stringUtils.hpp"
48
49 class RegMask;
50 // #include "phase.hpp"
51 class PhaseTransform;
52 class PhaseGVN;
53
54 // Arena we are currently building Nodes in
55 const uint Node::NotAMachineReg = 0xffff0000;
56
57 #ifndef PRODUCT
58 extern uint nodes_created;
59 #endif
60 #ifdef __clang__
61 #pragma clang diagnostic push
62 #pragma GCC diagnostic ignored "-Wuninitialized"
63 #endif
64
65 #ifdef ASSERT
66
67 //-------------------------- construct_node------------------------------------
68 // Set a breakpoint here to identify where a particular node index is built.
69 void Node::verify_construction() {
70 _debug_orig = nullptr;
71 // The decimal digits of _debug_idx are <compile_id> followed by 10 digits of <_idx>
72 Compile* C = Compile::current();
73 assert(C->unique() < (INT_MAX - 1), "Node limit exceeded INT_MAX");
74 uint64_t new_debug_idx = (uint64_t)C->compile_id() * 10000000000 + _idx;
75 set_debug_idx(new_debug_idx);
76 if (!C->phase_optimize_finished()) {
77 // Only check assert during parsing and optimization phase. Skip it while generating code.
78 assert(C->live_nodes() <= C->max_node_limit(), "Live Node limit exceeded limit");
79 }
80 if (BreakAtNode != 0 && (_debug_idx == BreakAtNode || (uint64_t)_idx == BreakAtNode)) {
81 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=" UINT64_FORMAT, _idx, _debug_idx);
82 BREAKPOINT;
83 }
84 #if OPTO_DU_ITERATOR_ASSERT
85 _last_del = nullptr;
86 _del_tick = 0;
87 #endif
88 _hash_lock = 0;
89 }
90
91
92 // #ifdef ASSERT ...
93
94 #if OPTO_DU_ITERATOR_ASSERT
95 void DUIterator_Common::sample(const Node* node) {
96 _vdui = VerifyDUIterators;
97 _node = node;
98 _outcnt = node->_outcnt;
99 _del_tick = node->_del_tick;
100 _last = nullptr;
101 }
102
103 void DUIterator_Common::verify(const Node* node, bool at_end_ok) {
104 assert(_node == node, "consistent iterator source");
105 assert(_del_tick == node->_del_tick, "no unexpected deletions allowed");
106 }
107
108 void DUIterator_Common::verify_resync() {
109 // Ensure that the loop body has just deleted the last guy produced.
110 const Node* node = _node;
111 // Ensure that at least one copy of the last-seen edge was deleted.
112 // Note: It is OK to delete multiple copies of the last-seen edge.
113 // Unfortunately, we have no way to verify that all the deletions delete
114 // that same edge. On this point we must use the Honor System.
115 assert(node->_del_tick >= _del_tick+1, "must have deleted an edge");
116 assert(node->_last_del == _last, "must have deleted the edge just produced");
117 // We liked this deletion, so accept the resulting outcnt and tick.
118 _outcnt = node->_outcnt;
119 _del_tick = node->_del_tick;
120 }
121
122 void DUIterator_Common::reset(const DUIterator_Common& that) {
123 if (this == &that) return; // ignore assignment to self
124 if (!_vdui) {
125 // We need to initialize everything, overwriting garbage values.
126 _last = that._last;
127 _vdui = that._vdui;
128 }
129 // Note: It is legal (though odd) for an iterator over some node x
130 // to be reassigned to iterate over another node y. Some doubly-nested
131 // progress loops depend on being able to do this.
132 const Node* node = that._node;
133 // Re-initialize everything, except _last.
134 _node = node;
135 _outcnt = node->_outcnt;
136 _del_tick = node->_del_tick;
137 }
138
139 void DUIterator::sample(const Node* node) {
140 DUIterator_Common::sample(node); // Initialize the assertion data.
141 _refresh_tick = 0; // No refreshes have happened, as yet.
142 }
143
144 void DUIterator::verify(const Node* node, bool at_end_ok) {
145 DUIterator_Common::verify(node, at_end_ok);
146 assert(_idx < node->_outcnt + (uint)at_end_ok, "idx in range");
147 }
148
149 void DUIterator::verify_increment() {
150 if (_refresh_tick & 1) {
151 // We have refreshed the index during this loop.
152 // Fix up _idx to meet asserts.
153 if (_idx > _outcnt) _idx = _outcnt;
154 }
155 verify(_node, true);
156 }
157
158 void DUIterator::verify_resync() {
159 // Note: We do not assert on _outcnt, because insertions are OK here.
160 DUIterator_Common::verify_resync();
161 // Make sure we are still in sync, possibly with no more out-edges:
162 verify(_node, true);
163 }
164
165 void DUIterator::reset(const DUIterator& that) {
166 if (this == &that) return; // self assignment is always a no-op
167 assert(that._refresh_tick == 0, "assign only the result of Node::outs()");
168 assert(that._idx == 0, "assign only the result of Node::outs()");
169 assert(_idx == that._idx, "already assigned _idx");
170 if (!_vdui) {
171 // We need to initialize everything, overwriting garbage values.
172 sample(that._node);
173 } else {
174 DUIterator_Common::reset(that);
175 if (_refresh_tick & 1) {
176 _refresh_tick++; // Clear the "was refreshed" flag.
177 }
178 assert(_refresh_tick < 2*100000, "DU iteration must converge quickly");
179 }
180 }
181
182 void DUIterator::refresh() {
183 DUIterator_Common::sample(_node); // Re-fetch assertion data.
184 _refresh_tick |= 1; // Set the "was refreshed" flag.
185 }
186
187 void DUIterator::verify_finish() {
188 // If the loop has killed the node, do not require it to re-run.
189 if (_node->_outcnt == 0) _refresh_tick &= ~1;
190 // If this assert triggers, it means that a loop used refresh_out_pos
191 // to re-synch an iteration index, but the loop did not correctly
192 // re-run itself, using a "while (progress)" construct.
193 // This iterator enforces the rule that you must keep trying the loop
194 // until it "runs clean" without any need for refreshing.
195 assert(!(_refresh_tick & 1), "the loop must run once with no refreshing");
196 }
197
198
199 void DUIterator_Fast::verify(const Node* node, bool at_end_ok) {
200 DUIterator_Common::verify(node, at_end_ok);
201 Node** out = node->_out;
202 uint cnt = node->_outcnt;
203 assert(cnt == _outcnt, "no insertions allowed");
204 assert(_outp >= out && _outp <= out + cnt - !at_end_ok, "outp in range");
205 // This last check is carefully designed to work for NO_OUT_ARRAY.
206 }
207
208 void DUIterator_Fast::verify_limit() {
209 const Node* node = _node;
210 verify(node, true);
211 assert(_outp == node->_out + node->_outcnt, "limit still correct");
212 }
213
214 void DUIterator_Fast::verify_resync() {
215 const Node* node = _node;
216 if (_outp == node->_out + _outcnt) {
217 // Note that the limit imax, not the pointer i, gets updated with the
218 // exact count of deletions. (For the pointer it's always "--i".)
219 assert(node->_outcnt+node->_del_tick == _outcnt+_del_tick, "no insertions allowed with deletion(s)");
220 // This is a limit pointer, with a name like "imax".
221 // Fudge the _last field so that the common assert will be happy.
222 _last = (Node*) node->_last_del;
223 DUIterator_Common::verify_resync();
224 } else {
225 assert(node->_outcnt < _outcnt, "no insertions allowed with deletion(s)");
226 // A normal internal pointer.
227 DUIterator_Common::verify_resync();
228 // Make sure we are still in sync, possibly with no more out-edges:
229 verify(node, true);
230 }
231 }
232
233 void DUIterator_Fast::verify_relimit(uint n) {
234 const Node* node = _node;
235 assert((int)n > 0, "use imax -= n only with a positive count");
236 // This must be a limit pointer, with a name like "imax".
237 assert(_outp == node->_out + node->_outcnt, "apply -= only to a limit (imax)");
238 // The reported number of deletions must match what the node saw.
239 assert(node->_del_tick == _del_tick + n, "must have deleted n edges");
240 // Fudge the _last field so that the common assert will be happy.
241 _last = (Node*) node->_last_del;
242 DUIterator_Common::verify_resync();
243 }
244
245 void DUIterator_Fast::reset(const DUIterator_Fast& that) {
246 assert(_outp == that._outp, "already assigned _outp");
247 DUIterator_Common::reset(that);
248 }
249
250 void DUIterator_Last::verify(const Node* node, bool at_end_ok) {
251 // at_end_ok means the _outp is allowed to underflow by 1
252 _outp += at_end_ok;
253 DUIterator_Fast::verify(node, at_end_ok); // check _del_tick, etc.
254 _outp -= at_end_ok;
255 assert(_outp == (node->_out + node->_outcnt) - 1, "pointer must point to end of nodes");
256 }
257
258 void DUIterator_Last::verify_limit() {
259 // Do not require the limit address to be resynched.
260 //verify(node, true);
261 assert(_outp == _node->_out, "limit still correct");
262 }
263
264 void DUIterator_Last::verify_step(uint num_edges) {
265 assert((int)num_edges > 0, "need non-zero edge count for loop progress");
266 _outcnt -= num_edges;
267 _del_tick += num_edges;
268 // Make sure we are still in sync, possibly with no more out-edges:
269 const Node* node = _node;
270 verify(node, true);
271 assert(node->_last_del == _last, "must have deleted the edge just produced");
272 }
273
274 #endif //OPTO_DU_ITERATOR_ASSERT
275
276
277 #endif //ASSERT
278
279
280 // This constant used to initialize _out may be any non-null value.
281 // The value null is reserved for the top node only.
282 #define NO_OUT_ARRAY ((Node**)-1)
283
284 // Out-of-line code from node constructors.
285 // Executed only when extra debug info. is being passed around.
286 static void init_node_notes(Compile* C, int idx, Node_Notes* nn) {
287 C->set_node_notes_at(idx, nn);
288 }
289
290 // Shared initialization code.
291 inline int Node::Init(int req) {
292 Compile* C = Compile::current();
293 int idx = C->next_unique();
294 NOT_PRODUCT(_igv_idx = C->next_igv_idx());
295
296 // Allocate memory for the necessary number of edges.
297 if (req > 0) {
298 // Allocate space for _in array to have double alignment.
299 _in = (Node **) ((char *) (C->node_arena()->AmallocWords(req * sizeof(void*))));
300 }
301 // If there are default notes floating around, capture them:
302 Node_Notes* nn = C->default_node_notes();
303 if (nn != nullptr) init_node_notes(C, idx, nn);
304
305 // Note: At this point, C is dead,
306 // and we begin to initialize the new Node.
307
308 _cnt = _max = req;
309 _outcnt = _outmax = 0;
310 _class_id = Class_Node;
311 _flags = 0;
312 _out = NO_OUT_ARRAY;
313 return idx;
314 }
315
316 //------------------------------Node-------------------------------------------
317 // Create a Node, with a given number of required edges.
318 Node::Node(uint req)
319 : _idx(Init(req))
320 #ifdef ASSERT
321 , _parse_idx(_idx)
322 #endif
323 {
324 assert( req < Compile::current()->max_node_limit() - NodeLimitFudgeFactor, "Input limit exceeded" );
325 debug_only( verify_construction() );
326 NOT_PRODUCT(nodes_created++);
327 if (req == 0) {
328 _in = nullptr;
329 } else {
330 Node** to = _in;
331 for(uint i = 0; i < req; i++) {
332 to[i] = nullptr;
333 }
334 }
335 }
336
337 //------------------------------Node-------------------------------------------
338 Node::Node(Node *n0)
339 : _idx(Init(1))
340 #ifdef ASSERT
341 , _parse_idx(_idx)
342 #endif
343 {
344 debug_only( verify_construction() );
345 NOT_PRODUCT(nodes_created++);
346 assert( is_not_dead(n0), "can not use dead node");
347 _in[0] = n0; if (n0 != nullptr) n0->add_out((Node *)this);
348 }
349
350 //------------------------------Node-------------------------------------------
351 Node::Node(Node *n0, Node *n1)
352 : _idx(Init(2))
353 #ifdef ASSERT
354 , _parse_idx(_idx)
355 #endif
356 {
357 debug_only( verify_construction() );
358 NOT_PRODUCT(nodes_created++);
359 assert( is_not_dead(n0), "can not use dead node");
360 assert( is_not_dead(n1), "can not use dead node");
361 _in[0] = n0; if (n0 != nullptr) n0->add_out((Node *)this);
362 _in[1] = n1; if (n1 != nullptr) n1->add_out((Node *)this);
363 }
364
365 //------------------------------Node-------------------------------------------
366 Node::Node(Node *n0, Node *n1, Node *n2)
367 : _idx(Init(3))
368 #ifdef ASSERT
369 , _parse_idx(_idx)
370 #endif
371 {
372 debug_only( verify_construction() );
373 NOT_PRODUCT(nodes_created++);
374 assert( is_not_dead(n0), "can not use dead node");
375 assert( is_not_dead(n1), "can not use dead node");
376 assert( is_not_dead(n2), "can not use dead node");
377 _in[0] = n0; if (n0 != nullptr) n0->add_out((Node *)this);
378 _in[1] = n1; if (n1 != nullptr) n1->add_out((Node *)this);
379 _in[2] = n2; if (n2 != nullptr) n2->add_out((Node *)this);
380 }
381
382 //------------------------------Node-------------------------------------------
383 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3)
384 : _idx(Init(4))
385 #ifdef ASSERT
386 , _parse_idx(_idx)
387 #endif
388 {
389 debug_only( verify_construction() );
390 NOT_PRODUCT(nodes_created++);
391 assert( is_not_dead(n0), "can not use dead node");
392 assert( is_not_dead(n1), "can not use dead node");
393 assert( is_not_dead(n2), "can not use dead node");
394 assert( is_not_dead(n3), "can not use dead node");
395 _in[0] = n0; if (n0 != nullptr) n0->add_out((Node *)this);
396 _in[1] = n1; if (n1 != nullptr) n1->add_out((Node *)this);
397 _in[2] = n2; if (n2 != nullptr) n2->add_out((Node *)this);
398 _in[3] = n3; if (n3 != nullptr) n3->add_out((Node *)this);
399 }
400
401 //------------------------------Node-------------------------------------------
402 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3, Node *n4)
403 : _idx(Init(5))
404 #ifdef ASSERT
405 , _parse_idx(_idx)
406 #endif
407 {
408 debug_only( verify_construction() );
409 NOT_PRODUCT(nodes_created++);
410 assert( is_not_dead(n0), "can not use dead node");
411 assert( is_not_dead(n1), "can not use dead node");
412 assert( is_not_dead(n2), "can not use dead node");
413 assert( is_not_dead(n3), "can not use dead node");
414 assert( is_not_dead(n4), "can not use dead node");
415 _in[0] = n0; if (n0 != nullptr) n0->add_out((Node *)this);
416 _in[1] = n1; if (n1 != nullptr) n1->add_out((Node *)this);
417 _in[2] = n2; if (n2 != nullptr) n2->add_out((Node *)this);
418 _in[3] = n3; if (n3 != nullptr) n3->add_out((Node *)this);
419 _in[4] = n4; if (n4 != nullptr) n4->add_out((Node *)this);
420 }
421
422 //------------------------------Node-------------------------------------------
423 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3,
424 Node *n4, Node *n5)
425 : _idx(Init(6))
426 #ifdef ASSERT
427 , _parse_idx(_idx)
428 #endif
429 {
430 debug_only( verify_construction() );
431 NOT_PRODUCT(nodes_created++);
432 assert( is_not_dead(n0), "can not use dead node");
433 assert( is_not_dead(n1), "can not use dead node");
434 assert( is_not_dead(n2), "can not use dead node");
435 assert( is_not_dead(n3), "can not use dead node");
436 assert( is_not_dead(n4), "can not use dead node");
437 assert( is_not_dead(n5), "can not use dead node");
438 _in[0] = n0; if (n0 != nullptr) n0->add_out((Node *)this);
439 _in[1] = n1; if (n1 != nullptr) n1->add_out((Node *)this);
440 _in[2] = n2; if (n2 != nullptr) n2->add_out((Node *)this);
441 _in[3] = n3; if (n3 != nullptr) n3->add_out((Node *)this);
442 _in[4] = n4; if (n4 != nullptr) n4->add_out((Node *)this);
443 _in[5] = n5; if (n5 != nullptr) n5->add_out((Node *)this);
444 }
445
446 //------------------------------Node-------------------------------------------
447 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3,
448 Node *n4, Node *n5, Node *n6)
449 : _idx(Init(7))
450 #ifdef ASSERT
451 , _parse_idx(_idx)
452 #endif
453 {
454 debug_only( verify_construction() );
455 NOT_PRODUCT(nodes_created++);
456 assert( is_not_dead(n0), "can not use dead node");
457 assert( is_not_dead(n1), "can not use dead node");
458 assert( is_not_dead(n2), "can not use dead node");
459 assert( is_not_dead(n3), "can not use dead node");
460 assert( is_not_dead(n4), "can not use dead node");
461 assert( is_not_dead(n5), "can not use dead node");
462 assert( is_not_dead(n6), "can not use dead node");
463 _in[0] = n0; if (n0 != nullptr) n0->add_out((Node *)this);
464 _in[1] = n1; if (n1 != nullptr) n1->add_out((Node *)this);
465 _in[2] = n2; if (n2 != nullptr) n2->add_out((Node *)this);
466 _in[3] = n3; if (n3 != nullptr) n3->add_out((Node *)this);
467 _in[4] = n4; if (n4 != nullptr) n4->add_out((Node *)this);
468 _in[5] = n5; if (n5 != nullptr) n5->add_out((Node *)this);
469 _in[6] = n6; if (n6 != nullptr) n6->add_out((Node *)this);
470 }
471
472 #ifdef __clang__
473 #pragma clang diagnostic pop
474 #endif
475
476
477 //------------------------------clone------------------------------------------
478 // Clone a Node.
479 Node *Node::clone() const {
480 Compile* C = Compile::current();
481 uint s = size_of(); // Size of inherited Node
482 Node *n = (Node*)C->node_arena()->AmallocWords(size_of() + _max*sizeof(Node*));
483 Copy::conjoint_words_to_lower((HeapWord*)this, (HeapWord*)n, s);
484 // Set the new input pointer array
485 n->_in = (Node**)(((char*)n)+s);
486 // Cannot share the old output pointer array, so kill it
487 n->_out = NO_OUT_ARRAY;
488 // And reset the counters to 0
489 n->_outcnt = 0;
490 n->_outmax = 0;
491 // Unlock this guy, since he is not in any hash table.
492 debug_only(n->_hash_lock = 0);
493 // Walk the old node's input list to duplicate its edges
494 uint i;
495 for( i = 0; i < len(); i++ ) {
496 Node *x = in(i);
497 n->_in[i] = x;
498 if (x != nullptr) x->add_out(n);
499 }
500 if (is_macro()) {
501 C->add_macro_node(n);
502 }
503 if (is_expensive()) {
504 C->add_expensive_node(n);
505 }
506 if (for_post_loop_opts_igvn()) {
507 // Don't add cloned node to Compile::_for_post_loop_opts_igvn list automatically.
508 // If it is applicable, it will happen anyway when the cloned node is registered with IGVN.
509 n->remove_flag(Node::NodeFlags::Flag_for_post_loop_opts_igvn);
510 }
511 if (for_merge_stores_igvn()) {
512 // Don't add cloned node to Compile::_for_merge_stores_igvn list automatically.
513 // If it is applicable, it will happen anyway when the cloned node is registered with IGVN.
514 n->remove_flag(Node::NodeFlags::Flag_for_merge_stores_igvn);
515 }
516 if (n->is_ParsePredicate()) {
517 C->add_parse_predicate(n->as_ParsePredicate());
518 }
519 if (n->is_OpaqueTemplateAssertionPredicate()) {
520 C->add_template_assertion_predicate_opaque(n->as_OpaqueTemplateAssertionPredicate());
521 }
522
523 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
524 bs->register_potential_barrier_node(n);
525
526 n->set_idx(C->next_unique()); // Get new unique index as well
527 NOT_PRODUCT(n->_igv_idx = C->next_igv_idx());
528 debug_only( n->verify_construction() );
529 NOT_PRODUCT(nodes_created++);
530 // Do not patch over the debug_idx of a clone, because it makes it
531 // impossible to break on the clone's moment of creation.
532 //debug_only( n->set_debug_idx( debug_idx() ) );
533
534 C->copy_node_notes_to(n, (Node*) this);
535
536 // MachNode clone
537 uint nopnds;
538 if (this->is_Mach() && (nopnds = this->as_Mach()->num_opnds()) > 0) {
539 MachNode *mach = n->as_Mach();
540 MachNode *mthis = this->as_Mach();
541 // Get address of _opnd_array.
542 // It should be the same offset since it is the clone of this node.
543 MachOper **from = mthis->_opnds;
544 MachOper **to = (MachOper **)((size_t)(&mach->_opnds) +
545 pointer_delta((const void*)from,
546 (const void*)(&mthis->_opnds), 1));
547 mach->_opnds = to;
548 for ( uint i = 0; i < nopnds; ++i ) {
549 to[i] = from[i]->clone();
550 }
551 }
552 if (n->is_Call()) {
553 // CallGenerator is linked to the original node.
554 CallGenerator* cg = n->as_Call()->generator();
555 if (cg != nullptr) {
556 CallGenerator* cloned_cg = cg->with_call_node(n->as_Call());
557 n->as_Call()->set_generator(cloned_cg);
558 }
559 }
560 if (n->is_SafePoint()) {
561 // Scalar replacement and macro expansion might modify the JVMState.
562 // Clone it to make sure it's not shared between SafePointNodes.
563 n->as_SafePoint()->clone_jvms(C);
564 n->as_SafePoint()->clone_replaced_nodes();
565 }
566 Compile::current()->record_modified_node(n);
567 return n; // Return the clone
568 }
569
570 //---------------------------setup_is_top--------------------------------------
571 // Call this when changing the top node, to reassert the invariants
572 // required by Node::is_top. See Compile::set_cached_top_node.
573 void Node::setup_is_top() {
574 if (this == (Node*)Compile::current()->top()) {
575 // This node has just become top. Kill its out array.
576 _outcnt = _outmax = 0;
577 _out = nullptr; // marker value for top
578 assert(is_top(), "must be top");
579 } else {
580 if (_out == nullptr) _out = NO_OUT_ARRAY;
581 assert(!is_top(), "must not be top");
582 }
583 }
584
585 //------------------------------~Node------------------------------------------
586 // Fancy destructor; eagerly attempt to reclaim Node numberings and storage
587 void Node::destruct(PhaseValues* phase) {
588 Compile* compile = (phase != nullptr) ? phase->C : Compile::current();
589 if (phase != nullptr && phase->is_IterGVN()) {
590 phase->is_IterGVN()->_worklist.remove(this);
591 }
592 // If this is the most recently created node, reclaim its index. Otherwise,
593 // record the node as dead to keep liveness information accurate.
594 if ((uint)_idx+1 == compile->unique()) {
595 compile->set_unique(compile->unique()-1);
596 } else {
597 compile->record_dead_node(_idx);
598 }
599 // Clear debug info:
600 Node_Notes* nn = compile->node_notes_at(_idx);
601 if (nn != nullptr) nn->clear();
602 // Walk the input array, freeing the corresponding output edges
603 _cnt = _max; // forget req/prec distinction
604 uint i;
605 for( i = 0; i < _max; i++ ) {
606 set_req(i, nullptr);
607 //assert(def->out(def->outcnt()-1) == (Node *)this,"bad def-use hacking in reclaim");
608 }
609 assert(outcnt() == 0, "deleting a node must not leave a dangling use");
610
611 if (is_macro()) {
612 compile->remove_macro_node(this);
613 }
614 if (is_expensive()) {
615 compile->remove_expensive_node(this);
616 }
617 if (is_OpaqueTemplateAssertionPredicate()) {
618 compile->remove_template_assertion_predicate_opaque(as_OpaqueTemplateAssertionPredicate());
619 }
620 if (is_ParsePredicate()) {
621 compile->remove_parse_predicate(as_ParsePredicate());
622 }
623 if (for_post_loop_opts_igvn()) {
624 compile->remove_from_post_loop_opts_igvn(this);
625 }
626 if (for_merge_stores_igvn()) {
627 compile->remove_from_merge_stores_igvn(this);
628 }
629
630 if (is_SafePoint()) {
631 as_SafePoint()->delete_replaced_nodes();
632
633 if (is_CallStaticJava()) {
634 compile->remove_unstable_if_trap(as_CallStaticJava(), false);
635 }
636 }
637 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
638 bs->unregister_potential_barrier_node(this);
639
640 // See if the input array was allocated just prior to the object
641 int edge_size = _max*sizeof(void*);
642 int out_edge_size = _outmax*sizeof(void*);
643 char *in_array = ((char*)_in);
644 char *edge_end = in_array + edge_size;
645 char *out_array = (char*)(_out == NO_OUT_ARRAY? nullptr: _out);
646 int node_size = size_of();
647
648 #ifdef ASSERT
649 // We will not actually delete the storage, but we'll make the node unusable.
650 compile->remove_modified_node(this);
651 *(address*)this = badAddress; // smash the C++ vtbl, probably
652 _in = _out = (Node**) badAddress;
653 _max = _cnt = _outmax = _outcnt = 0;
654 #endif
655
656 // Free the output edge array
657 if (out_edge_size > 0) {
658 compile->node_arena()->Afree(out_array, out_edge_size);
659 }
660
661 // Free the input edge array and the node itself
662 if( edge_end == (char*)this ) {
663 // It was; free the input array and object all in one hit
664 #ifndef ASSERT
665 compile->node_arena()->Afree(in_array, edge_size+node_size);
666 #endif
667 } else {
668 // Free just the input array
669 compile->node_arena()->Afree(in_array, edge_size);
670
671 // Free just the object
672 #ifndef ASSERT
673 compile->node_arena()->Afree(this, node_size);
674 #endif
675 }
676 }
677
678 // Resize input or output array to grow it to the next larger power-of-2 bigger
679 // than len.
680 void Node::resize_array(Node**& array, node_idx_t& max_size, uint len, bool needs_clearing) {
681 Arena* arena = Compile::current()->node_arena();
682 uint new_max = max_size;
683 if (new_max == 0) {
684 max_size = 4;
685 array = (Node**)arena->Amalloc(4 * sizeof(Node*));
686 if (needs_clearing) {
687 array[0] = nullptr;
688 array[1] = nullptr;
689 array[2] = nullptr;
690 array[3] = nullptr;
691 }
692 return;
693 }
694 new_max = next_power_of_2(len);
695 assert(needs_clearing || (array != nullptr && array != NO_OUT_ARRAY), "out must have sensible value");
696 array = (Node**)arena->Arealloc(array, max_size * sizeof(Node*), new_max * sizeof(Node*));
697 if (needs_clearing) {
698 Copy::zero_to_bytes(&array[max_size], (new_max - max_size) * sizeof(Node*)); // null all new space
699 }
700 max_size = new_max; // Record new max length
701 // This assertion makes sure that Node::_max is wide enough to
702 // represent the numerical value of new_max.
703 assert(max_size > len, "int width of _max or _outmax is too small");
704 }
705
706 //------------------------------grow-------------------------------------------
707 // Grow the input array, making space for more edges
708 void Node::grow(uint len) {
709 resize_array(_in, _max, len, true);
710 }
711
712 //-----------------------------out_grow----------------------------------------
713 // Grow the input array, making space for more edges
714 void Node::out_grow(uint len) {
715 assert(!is_top(), "cannot grow a top node's out array");
716 resize_array(_out, _outmax, len, false);
717 }
718
719 #ifdef ASSERT
720 //------------------------------is_dead----------------------------------------
721 bool Node::is_dead() const {
722 // Mach and pinch point nodes may look like dead.
723 if( is_top() || is_Mach() || (Opcode() == Op_Node && _outcnt > 0) )
724 return false;
725 for( uint i = 0; i < _max; i++ )
726 if( _in[i] != nullptr )
727 return false;
728 return true;
729 }
730
731 bool Node::is_not_dead(const Node* n) {
732 return n == nullptr || !PhaseIterGVN::is_verify_def_use() || !(n->is_dead());
733 }
734
735 bool Node::is_reachable_from_root() const {
736 ResourceMark rm;
737 Unique_Node_List wq;
738 wq.push((Node*)this);
739 RootNode* root = Compile::current()->root();
740 for (uint i = 0; i < wq.size(); i++) {
741 Node* m = wq.at(i);
742 if (m == root) {
743 return true;
744 }
745 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
746 Node* u = m->fast_out(j);
747 wq.push(u);
748 }
749 }
750 return false;
751 }
752 #endif
753
754 //------------------------------is_unreachable---------------------------------
755 bool Node::is_unreachable(PhaseIterGVN &igvn) const {
756 assert(!is_Mach(), "doesn't work with MachNodes");
757 return outcnt() == 0 || igvn.type(this) == Type::TOP || (in(0) != nullptr && in(0)->is_top());
758 }
759
760 //------------------------------add_req----------------------------------------
761 // Add a new required input at the end
762 void Node::add_req( Node *n ) {
763 assert( is_not_dead(n), "can not use dead node");
764
765 // Look to see if I can move precedence down one without reallocating
766 if( (_cnt >= _max) || (in(_max-1) != nullptr) )
767 grow( _max+1 );
768
769 // Find a precedence edge to move
770 if( in(_cnt) != nullptr ) { // Next precedence edge is busy?
771 uint i;
772 for( i=_cnt; i<_max; i++ )
773 if( in(i) == nullptr ) // Find the null at end of prec edge list
774 break; // There must be one, since we grew the array
775 _in[i] = in(_cnt); // Move prec over, making space for req edge
776 }
777 _in[_cnt++] = n; // Stuff over old prec edge
778 if (n != nullptr) n->add_out((Node *)this);
779 Compile::current()->record_modified_node(this);
780 }
781
782 //---------------------------add_req_batch-------------------------------------
783 // Add a new required input at the end
784 void Node::add_req_batch( Node *n, uint m ) {
785 assert( is_not_dead(n), "can not use dead node");
786 // check various edge cases
787 if ((int)m <= 1) {
788 assert((int)m >= 0, "oob");
789 if (m != 0) add_req(n);
790 return;
791 }
792
793 // Look to see if I can move precedence down one without reallocating
794 if( (_cnt+m) > _max || _in[_max-m] )
795 grow( _max+m );
796
797 // Find a precedence edge to move
798 if( _in[_cnt] != nullptr ) { // Next precedence edge is busy?
799 uint i;
800 for( i=_cnt; i<_max; i++ )
801 if( _in[i] == nullptr ) // Find the null at end of prec edge list
802 break; // There must be one, since we grew the array
803 // Slide all the precs over by m positions (assume #prec << m).
804 Copy::conjoint_words_to_higher((HeapWord*)&_in[_cnt], (HeapWord*)&_in[_cnt+m], ((i-_cnt)*sizeof(Node*)));
805 }
806
807 // Stuff over the old prec edges
808 for(uint i=0; i<m; i++ ) {
809 _in[_cnt++] = n;
810 }
811
812 // Insert multiple out edges on the node.
813 if (n != nullptr && !n->is_top()) {
814 for(uint i=0; i<m; i++ ) {
815 n->add_out((Node *)this);
816 }
817 }
818 Compile::current()->record_modified_node(this);
819 }
820
821 //------------------------------del_req----------------------------------------
822 // Delete the required edge and compact the edge array
823 void Node::del_req( uint idx ) {
824 assert( idx < _cnt, "oob");
825 assert( !VerifyHashTableKeys || _hash_lock == 0,
826 "remove node from hash table before modifying it");
827 // First remove corresponding def-use edge
828 Node *n = in(idx);
829 if (n != nullptr) n->del_out((Node *)this);
830 _in[idx] = in(--_cnt); // Compact the array
831 // Avoid spec violation: Gap in prec edges.
832 close_prec_gap_at(_cnt);
833 Compile::current()->record_modified_node(this);
834 }
835
836 //------------------------------del_req_ordered--------------------------------
837 // Delete the required edge and compact the edge array with preserved order
838 void Node::del_req_ordered( uint idx ) {
839 assert( idx < _cnt, "oob");
840 assert( !VerifyHashTableKeys || _hash_lock == 0,
841 "remove node from hash table before modifying it");
842 // First remove corresponding def-use edge
843 Node *n = in(idx);
844 if (n != nullptr) n->del_out((Node *)this);
845 if (idx < --_cnt) { // Not last edge ?
846 Copy::conjoint_words_to_lower((HeapWord*)&_in[idx+1], (HeapWord*)&_in[idx], ((_cnt-idx)*sizeof(Node*)));
847 }
848 // Avoid spec violation: Gap in prec edges.
849 close_prec_gap_at(_cnt);
850 Compile::current()->record_modified_node(this);
851 }
852
853 //------------------------------ins_req----------------------------------------
854 // Insert a new required input at the end
855 void Node::ins_req( uint idx, Node *n ) {
856 assert( is_not_dead(n), "can not use dead node");
857 add_req(nullptr); // Make space
858 assert( idx < _max, "Must have allocated enough space");
859 // Slide over
860 if(_cnt-idx-1 > 0) {
861 Copy::conjoint_words_to_higher((HeapWord*)&_in[idx], (HeapWord*)&_in[idx+1], ((_cnt-idx-1)*sizeof(Node*)));
862 }
863 _in[idx] = n; // Stuff over old required edge
864 if (n != nullptr) n->add_out((Node *)this); // Add reciprocal def-use edge
865 Compile::current()->record_modified_node(this);
866 }
867
868 //-----------------------------find_edge---------------------------------------
869 int Node::find_edge(Node* n) {
870 for (uint i = 0; i < len(); i++) {
871 if (_in[i] == n) return i;
872 }
873 return -1;
874 }
875
876 //----------------------------replace_edge-------------------------------------
877 int Node::replace_edge(Node* old, Node* neww, PhaseGVN* gvn) {
878 if (old == neww) return 0; // nothing to do
879 uint nrep = 0;
880 for (uint i = 0; i < len(); i++) {
881 if (in(i) == old) {
882 if (i < req()) {
883 if (gvn != nullptr) {
884 set_req_X(i, neww, gvn);
885 } else {
886 set_req(i, neww);
887 }
888 } else {
889 assert(gvn == nullptr || gvn->is_IterGVN() == nullptr, "no support for igvn here");
890 assert(find_prec_edge(neww) == -1, "spec violation: duplicated prec edge (node %d -> %d)", _idx, neww->_idx);
891 set_prec(i, neww);
892 }
893 nrep++;
894 }
895 }
896 return nrep;
897 }
898
899 /**
900 * Replace input edges in the range pointing to 'old' node.
901 */
902 int Node::replace_edges_in_range(Node* old, Node* neww, int start, int end, PhaseGVN* gvn) {
903 if (old == neww) return 0; // nothing to do
904 uint nrep = 0;
905 for (int i = start; i < end; i++) {
906 if (in(i) == old) {
907 set_req_X(i, neww, gvn);
908 nrep++;
909 }
910 }
911 return nrep;
912 }
913
914 //-------------------------disconnect_inputs-----------------------------------
915 // null out all inputs to eliminate incoming Def-Use edges.
916 void Node::disconnect_inputs(Compile* C) {
917 // the layout of Node::_in
918 // r: a required input, null is allowed
919 // p: a precedence, null values are all at the end
920 // -----------------------------------
921 // |r|...|r|p|...|p|null|...|null|
922 // | |
923 // req() len()
924 // -----------------------------------
925 for (uint i = 0; i < req(); ++i) {
926 if (in(i) != nullptr) {
927 set_req(i, nullptr);
928 }
929 }
930
931 // Remove precedence edges if any exist
932 // Note: Safepoints may have precedence edges, even during parsing
933 for (uint i = len(); i > req(); ) {
934 rm_prec(--i); // no-op if _in[i] is null
935 }
936
937 #ifdef ASSERT
938 // sanity check
939 for (uint i = 0; i < len(); ++i) {
940 assert(_in[i] == nullptr, "disconnect_inputs() failed!");
941 }
942 #endif
943
944 // Node::destruct requires all out edges be deleted first
945 // debug_only(destruct();) // no reuse benefit expected
946 C->record_dead_node(_idx);
947 }
948
949 //-----------------------------uncast---------------------------------------
950 // %%% Temporary, until we sort out CheckCastPP vs. CastPP.
951 // Strip away casting. (It is depth-limited.)
952 // Optionally, keep casts with dependencies.
953 Node* Node::uncast(bool keep_deps) const {
954 // Should be inline:
955 //return is_ConstraintCast() ? uncast_helper(this) : (Node*) this;
956 if (is_ConstraintCast()) {
957 return uncast_helper(this, keep_deps);
958 } else {
959 return (Node*) this;
960 }
961 }
962
963 // Find out of current node that matches opcode.
964 Node* Node::find_out_with(int opcode) {
965 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
966 Node* use = fast_out(i);
967 if (use->Opcode() == opcode) {
968 return use;
969 }
970 }
971 return nullptr;
972 }
973
974 // Return true if the current node has an out that matches opcode.
975 bool Node::has_out_with(int opcode) {
976 return (find_out_with(opcode) != nullptr);
977 }
978
979 // Return true if the current node has an out that matches any of the opcodes.
980 bool Node::has_out_with(int opcode1, int opcode2, int opcode3, int opcode4) {
981 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
982 int opcode = fast_out(i)->Opcode();
983 if (opcode == opcode1 || opcode == opcode2 || opcode == opcode3 || opcode == opcode4) {
984 return true;
985 }
986 }
987 return false;
988 }
989
990
991 //---------------------------uncast_helper-------------------------------------
992 Node* Node::uncast_helper(const Node* p, bool keep_deps) {
993 #ifdef ASSERT
994 uint depth_count = 0;
995 const Node* orig_p = p;
996 #endif
997
998 while (true) {
999 #ifdef ASSERT
1000 if (depth_count >= K) {
1001 orig_p->dump(4);
1002 if (p != orig_p)
1003 p->dump(1);
1004 }
1005 assert(depth_count++ < K, "infinite loop in Node::uncast_helper");
1006 #endif
1007 if (p == nullptr || p->req() != 2) {
1008 break;
1009 } else if (p->is_ConstraintCast()) {
1010 if (keep_deps && p->as_ConstraintCast()->carry_dependency()) {
1011 break; // stop at casts with dependencies
1012 }
1013 p = p->in(1);
1014 } else {
1015 break;
1016 }
1017 }
1018 return (Node*) p;
1019 }
1020
1021 //------------------------------add_prec---------------------------------------
1022 // Add a new precedence input. Precedence inputs are unordered, with
1023 // duplicates removed and nulls packed down at the end.
1024 void Node::add_prec( Node *n ) {
1025 assert( is_not_dead(n), "can not use dead node");
1026
1027 // Check for null at end
1028 if( _cnt >= _max || in(_max-1) )
1029 grow( _max+1 );
1030
1031 // Find a precedence edge to move
1032 uint i = _cnt;
1033 while( in(i) != nullptr ) {
1034 if (in(i) == n) return; // Avoid spec violation: duplicated prec edge.
1035 i++;
1036 }
1037 _in[i] = n; // Stuff prec edge over null
1038 if ( n != nullptr) n->add_out((Node *)this); // Add mirror edge
1039
1040 #ifdef ASSERT
1041 while ((++i)<_max) { assert(_in[i] == nullptr, "spec violation: Gap in prec edges (node %d)", _idx); }
1042 #endif
1043 Compile::current()->record_modified_node(this);
1044 }
1045
1046 //------------------------------rm_prec----------------------------------------
1047 // Remove a precedence input. Precedence inputs are unordered, with
1048 // duplicates removed and nulls packed down at the end.
1049 void Node::rm_prec( uint j ) {
1050 assert(j < _max, "oob: i=%d, _max=%d", j, _max);
1051 assert(j >= _cnt, "not a precedence edge");
1052 if (_in[j] == nullptr) return; // Avoid spec violation: Gap in prec edges.
1053 _in[j]->del_out((Node *)this);
1054 close_prec_gap_at(j);
1055 Compile::current()->record_modified_node(this);
1056 }
1057
1058 //------------------------------size_of----------------------------------------
1059 uint Node::size_of() const { return sizeof(*this); }
1060
1061 //------------------------------ideal_reg--------------------------------------
1062 uint Node::ideal_reg() const { return 0; }
1063
1064 //------------------------------jvms-------------------------------------------
1065 JVMState* Node::jvms() const { return nullptr; }
1066
1067 #ifdef ASSERT
1068 //------------------------------jvms-------------------------------------------
1069 bool Node::verify_jvms(const JVMState* using_jvms) const {
1070 for (JVMState* jvms = this->jvms(); jvms != nullptr; jvms = jvms->caller()) {
1071 if (jvms == using_jvms) return true;
1072 }
1073 return false;
1074 }
1075
1076 //------------------------------init_NodeProperty------------------------------
1077 void Node::init_NodeProperty() {
1078 assert(_max_classes <= max_juint, "too many NodeProperty classes");
1079 assert(max_flags() <= max_juint, "too many NodeProperty flags");
1080 }
1081
1082 //-----------------------------max_flags---------------------------------------
1083 juint Node::max_flags() {
1084 return (PD::_last_flag << 1) - 1; // allow flags combination
1085 }
1086 #endif
1087
1088 //------------------------------format-----------------------------------------
1089 // Print as assembly
1090 void Node::format( PhaseRegAlloc *, outputStream *st ) const {}
1091 //------------------------------emit-------------------------------------------
1092 // Emit bytes using C2_MacroAssembler
1093 void Node::emit(C2_MacroAssembler *masm, PhaseRegAlloc *ra_) const {}
1094 //------------------------------size-------------------------------------------
1095 // Size of instruction in bytes
1096 uint Node::size(PhaseRegAlloc *ra_) const { return 0; }
1097
1098 //------------------------------CFG Construction-------------------------------
1099 // Nodes that end basic blocks, e.g. IfTrue/IfFalse, JumpProjNode, Root,
1100 // Goto and Return.
1101 const Node *Node::is_block_proj() const { return nullptr; }
1102
1103 // Minimum guaranteed type
1104 const Type *Node::bottom_type() const { return Type::BOTTOM; }
1105
1106
1107 //------------------------------raise_bottom_type------------------------------
1108 // Get the worst-case Type output for this Node.
1109 void Node::raise_bottom_type(const Type* new_type) {
1110 if (is_Type()) {
1111 TypeNode *n = this->as_Type();
1112 if (VerifyAliases) {
1113 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1114 }
1115 n->set_type(new_type);
1116 } else if (is_Load()) {
1117 LoadNode *n = this->as_Load();
1118 if (VerifyAliases) {
1119 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1120 }
1121 n->set_type(new_type);
1122 }
1123 }
1124
1125 //------------------------------Identity---------------------------------------
1126 // Return a node that the given node is equivalent to.
1127 Node* Node::Identity(PhaseGVN* phase) {
1128 return this; // Default to no identities
1129 }
1130
1131 //------------------------------Value------------------------------------------
1132 // Compute a new Type for a node using the Type of the inputs.
1133 const Type* Node::Value(PhaseGVN* phase) const {
1134 return bottom_type(); // Default to worst-case Type
1135 }
1136
1137 //------------------------------Ideal------------------------------------------
1138 //
1139 // 'Idealize' the graph rooted at this Node.
1140 //
1141 // In order to be efficient and flexible there are some subtle invariants
1142 // these Ideal calls need to hold. Running with '-XX:VerifyIterativeGVN=1' checks
1143 // these invariants, although its too slow to have on by default. If you are
1144 // hacking an Ideal call, be sure to test with '-XX:VerifyIterativeGVN=1'
1145 //
1146 // The Ideal call almost arbitrarily reshape the graph rooted at the 'this'
1147 // pointer. If ANY change is made, it must return the root of the reshaped
1148 // graph - even if the root is the same Node. Example: swapping the inputs
1149 // to an AddINode gives the same answer and same root, but you still have to
1150 // return the 'this' pointer instead of null.
1151 //
1152 // You cannot return an OLD Node, except for the 'this' pointer. Use the
1153 // Identity call to return an old Node; basically if Identity can find
1154 // another Node have the Ideal call make no change and return null.
1155 // Example: AddINode::Ideal must check for add of zero; in this case it
1156 // returns null instead of doing any graph reshaping.
1157 //
1158 // You cannot modify any old Nodes except for the 'this' pointer. Due to
1159 // sharing there may be other users of the old Nodes relying on their current
1160 // semantics. Modifying them will break the other users.
1161 // Example: when reshape "(X+3)+4" into "X+7" you must leave the Node for
1162 // "X+3" unchanged in case it is shared.
1163 //
1164 // If you modify the 'this' pointer's inputs, you should use
1165 // 'set_req'. If you are making a new Node (either as the new root or
1166 // some new internal piece) you may use 'init_req' to set the initial
1167 // value. You can make a new Node with either 'new' or 'clone'. In
1168 // either case, def-use info is correctly maintained.
1169 //
1170 // Example: reshape "(X+3)+4" into "X+7":
1171 // set_req(1, in(1)->in(1));
1172 // set_req(2, phase->intcon(7));
1173 // return this;
1174 // Example: reshape "X*4" into "X<<2"
1175 // return new LShiftINode(in(1), phase->intcon(2));
1176 //
1177 // You must call 'phase->transform(X)' on any new Nodes X you make, except
1178 // for the returned root node. Example: reshape "X*31" with "(X<<5)-X".
1179 // Node *shift=phase->transform(new LShiftINode(in(1),phase->intcon(5)));
1180 // return new AddINode(shift, in(1));
1181 //
1182 // When making a Node for a constant use 'phase->makecon' or 'phase->intcon'.
1183 // These forms are faster than 'phase->transform(new ConNode())' and Do
1184 // The Right Thing with def-use info.
1185 //
1186 // You cannot bury the 'this' Node inside of a graph reshape. If the reshaped
1187 // graph uses the 'this' Node it must be the root. If you want a Node with
1188 // the same Opcode as the 'this' pointer use 'clone'.
1189 //
1190 Node *Node::Ideal(PhaseGVN *phase, bool can_reshape) {
1191 return nullptr; // Default to being Ideal already
1192 }
1193
1194 // Some nodes have specific Ideal subgraph transformations only if they are
1195 // unique users of specific nodes. Such nodes should be put on IGVN worklist
1196 // for the transformations to happen.
1197 bool Node::has_special_unique_user() const {
1198 assert(outcnt() == 1, "match only for unique out");
1199 Node* n = unique_out();
1200 int op = Opcode();
1201 if (this->is_Store()) {
1202 // Condition for back-to-back stores folding.
1203 return n->Opcode() == op && n->in(MemNode::Memory) == this;
1204 } else if (this->is_Load() || this->is_DecodeN() || this->is_Phi()) {
1205 // Condition for removing an unused LoadNode or DecodeNNode from the MemBarAcquire precedence input
1206 return n->Opcode() == Op_MemBarAcquire;
1207 } else if (op == Op_AddL) {
1208 // Condition for convL2I(addL(x,y)) ==> addI(convL2I(x),convL2I(y))
1209 return n->Opcode() == Op_ConvL2I && n->in(1) == this;
1210 } else if (op == Op_SubI || op == Op_SubL) {
1211 // Condition for subI(x,subI(y,z)) ==> subI(addI(x,z),y)
1212 return n->Opcode() == op && n->in(2) == this;
1213 } else if (is_If() && (n->is_IfFalse() || n->is_IfTrue())) {
1214 // See IfProjNode::Identity()
1215 return true;
1216 } else if ((is_IfFalse() || is_IfTrue()) && n->is_If()) {
1217 // See IfNode::fold_compares
1218 return true;
1219 } else {
1220 return false;
1221 }
1222 };
1223
1224 //--------------------------find_exact_control---------------------------------
1225 // Skip Proj and CatchProj nodes chains. Check for Null and Top.
1226 Node* Node::find_exact_control(Node* ctrl) {
1227 if (ctrl == nullptr && this->is_Region())
1228 ctrl = this->as_Region()->is_copy();
1229
1230 if (ctrl != nullptr && ctrl->is_CatchProj()) {
1231 if (ctrl->as_CatchProj()->_con == CatchProjNode::fall_through_index)
1232 ctrl = ctrl->in(0);
1233 if (ctrl != nullptr && !ctrl->is_top())
1234 ctrl = ctrl->in(0);
1235 }
1236
1237 if (ctrl != nullptr && ctrl->is_Proj())
1238 ctrl = ctrl->in(0);
1239
1240 return ctrl;
1241 }
1242
1243 //--------------------------dominates------------------------------------------
1244 // Helper function for MemNode::all_controls_dominate().
1245 // Check if 'this' control node dominates or equal to 'sub' control node.
1246 // We already know that if any path back to Root or Start reaches 'this',
1247 // then all paths so, so this is a simple search for one example,
1248 // not an exhaustive search for a counterexample.
1249 Node::DomResult Node::dominates(Node* sub, Node_List &nlist) {
1250 assert(this->is_CFG(), "expecting control");
1251 assert(sub != nullptr && sub->is_CFG(), "expecting control");
1252
1253 // detect dead cycle without regions
1254 int iterations_without_region_limit = DominatorSearchLimit;
1255
1256 Node* orig_sub = sub;
1257 Node* dom = this;
1258 bool met_dom = false;
1259 nlist.clear();
1260
1261 // Walk 'sub' backward up the chain to 'dom', watching for regions.
1262 // After seeing 'dom', continue up to Root or Start.
1263 // If we hit a region (backward split point), it may be a loop head.
1264 // Keep going through one of the region's inputs. If we reach the
1265 // same region again, go through a different input. Eventually we
1266 // will either exit through the loop head, or give up.
1267 // (If we get confused, break out and return a conservative 'false'.)
1268 while (sub != nullptr) {
1269 if (sub->is_top()) {
1270 // Conservative answer for dead code.
1271 return DomResult::EncounteredDeadCode;
1272 }
1273 if (sub == dom) {
1274 if (nlist.size() == 0) {
1275 // No Region nodes except loops were visited before and the EntryControl
1276 // path was taken for loops: it did not walk in a cycle.
1277 return DomResult::Dominate;
1278 } else if (met_dom) {
1279 break; // already met before: walk in a cycle
1280 } else {
1281 // Region nodes were visited. Continue walk up to Start or Root
1282 // to make sure that it did not walk in a cycle.
1283 met_dom = true; // first time meet
1284 iterations_without_region_limit = DominatorSearchLimit; // Reset
1285 }
1286 }
1287 if (sub->is_Start() || sub->is_Root()) {
1288 // Success if we met 'dom' along a path to Start or Root.
1289 // We assume there are no alternative paths that avoid 'dom'.
1290 // (This assumption is up to the caller to ensure!)
1291 return met_dom ? DomResult::Dominate : DomResult::NotDominate;
1292 }
1293 Node* up = sub->in(0);
1294 // Normalize simple pass-through regions and projections:
1295 up = sub->find_exact_control(up);
1296 // If sub == up, we found a self-loop. Try to push past it.
1297 if (sub == up && sub->is_Loop()) {
1298 // Take loop entry path on the way up to 'dom'.
1299 up = sub->in(1); // in(LoopNode::EntryControl);
1300 } else if (sub == up && sub->is_Region() && sub->req() == 2) {
1301 // Take in(1) path on the way up to 'dom' for regions with only one input
1302 up = sub->in(1);
1303 } else if (sub == up && sub->is_Region()) {
1304 // Try both paths for Regions with 2 input paths (it may be a loop head).
1305 // It could give conservative 'false' answer without information
1306 // which region's input is the entry path.
1307 iterations_without_region_limit = DominatorSearchLimit; // Reset
1308
1309 bool region_was_visited_before = false;
1310 // Was this Region node visited before?
1311 // If so, we have reached it because we accidentally took a
1312 // loop-back edge from 'sub' back into the body of the loop,
1313 // and worked our way up again to the loop header 'sub'.
1314 // So, take the first unexplored path on the way up to 'dom'.
1315 for (int j = nlist.size() - 1; j >= 0; j--) {
1316 intptr_t ni = (intptr_t)nlist.at(j);
1317 Node* visited = (Node*)(ni & ~1);
1318 bool visited_twice_already = ((ni & 1) != 0);
1319 if (visited == sub) {
1320 if (visited_twice_already) {
1321 // Visited 2 paths, but still stuck in loop body. Give up.
1322 return DomResult::NotDominate;
1323 }
1324 // The Region node was visited before only once.
1325 // (We will repush with the low bit set, below.)
1326 nlist.remove(j);
1327 // We will find a new edge and re-insert.
1328 region_was_visited_before = true;
1329 break;
1330 }
1331 }
1332
1333 // Find an incoming edge which has not been seen yet; walk through it.
1334 assert(up == sub, "");
1335 uint skip = region_was_visited_before ? 1 : 0;
1336 for (uint i = 1; i < sub->req(); i++) {
1337 Node* in = sub->in(i);
1338 if (in != nullptr && !in->is_top() && in != sub) {
1339 if (skip == 0) {
1340 up = in;
1341 break;
1342 }
1343 --skip; // skip this nontrivial input
1344 }
1345 }
1346
1347 // Set 0 bit to indicate that both paths were taken.
1348 nlist.push((Node*)((intptr_t)sub + (region_was_visited_before ? 1 : 0)));
1349 }
1350
1351 if (up == sub) {
1352 break; // some kind of tight cycle
1353 }
1354 if (up == orig_sub && met_dom) {
1355 // returned back after visiting 'dom'
1356 break; // some kind of cycle
1357 }
1358 if (--iterations_without_region_limit < 0) {
1359 break; // dead cycle
1360 }
1361 sub = up;
1362 }
1363
1364 // Did not meet Root or Start node in pred. chain.
1365 return DomResult::NotDominate;
1366 }
1367
1368 //------------------------------remove_dead_region-----------------------------
1369 // This control node is dead. Follow the subgraph below it making everything
1370 // using it dead as well. This will happen normally via the usual IterGVN
1371 // worklist but this call is more efficient. Do not update use-def info
1372 // inside the dead region, just at the borders.
1373 static void kill_dead_code( Node *dead, PhaseIterGVN *igvn ) {
1374 // Con's are a popular node to re-hit in the hash table again.
1375 if( dead->is_Con() ) return;
1376
1377 ResourceMark rm;
1378 Node_List nstack;
1379 VectorSet dead_set; // notify uses only once
1380
1381 Node *top = igvn->C->top();
1382 nstack.push(dead);
1383 bool has_irreducible_loop = igvn->C->has_irreducible_loop();
1384
1385 while (nstack.size() > 0) {
1386 dead = nstack.pop();
1387 if (!dead_set.test_set(dead->_idx)) {
1388 // If dead has any live uses, those are now still attached. Notify them before we lose them.
1389 igvn->add_users_to_worklist(dead);
1390 }
1391 if (dead->Opcode() == Op_SafePoint) {
1392 dead->as_SafePoint()->disconnect_from_root(igvn);
1393 }
1394 if (dead->outcnt() > 0) {
1395 // Keep dead node on stack until all uses are processed.
1396 nstack.push(dead);
1397 // For all Users of the Dead... ;-)
1398 for (DUIterator_Last kmin, k = dead->last_outs(kmin); k >= kmin; ) {
1399 Node* use = dead->last_out(k);
1400 igvn->hash_delete(use); // Yank from hash table prior to mod
1401 if (use->in(0) == dead) { // Found another dead node
1402 assert (!use->is_Con(), "Control for Con node should be Root node.");
1403 use->set_req(0, top); // Cut dead edge to prevent processing
1404 nstack.push(use); // the dead node again.
1405 } else if (!has_irreducible_loop && // Backedge could be alive in irreducible loop
1406 use->is_Loop() && !use->is_Root() && // Don't kill Root (RootNode extends LoopNode)
1407 use->in(LoopNode::EntryControl) == dead) { // Dead loop if its entry is dead
1408 use->set_req(LoopNode::EntryControl, top); // Cut dead edge to prevent processing
1409 use->set_req(0, top); // Cut self edge
1410 nstack.push(use);
1411 } else { // Else found a not-dead user
1412 // Dead if all inputs are top or null
1413 bool dead_use = !use->is_Root(); // Keep empty graph alive
1414 for (uint j = 1; j < use->req(); j++) {
1415 Node* in = use->in(j);
1416 if (in == dead) { // Turn all dead inputs into TOP
1417 use->set_req(j, top);
1418 } else if (in != nullptr && !in->is_top()) {
1419 dead_use = false;
1420 }
1421 }
1422 if (dead_use) {
1423 if (use->is_Region()) {
1424 use->set_req(0, top); // Cut self edge
1425 }
1426 nstack.push(use);
1427 } else {
1428 igvn->_worklist.push(use);
1429 }
1430 }
1431 // Refresh the iterator, since any number of kills might have happened.
1432 k = dead->last_outs(kmin);
1433 }
1434 } else { // (dead->outcnt() == 0)
1435 // Done with outputs.
1436 igvn->hash_delete(dead);
1437 igvn->_worklist.remove(dead);
1438 igvn->set_type(dead, Type::TOP);
1439 // Kill all inputs to the dead guy
1440 for (uint i=0; i < dead->req(); i++) {
1441 Node *n = dead->in(i); // Get input to dead guy
1442 if (n != nullptr && !n->is_top()) { // Input is valid?
1443 dead->set_req(i, top); // Smash input away
1444 if (n->outcnt() == 0) { // Input also goes dead?
1445 if (!n->is_Con())
1446 nstack.push(n); // Clear it out as well
1447 } else if (n->outcnt() == 1 &&
1448 n->has_special_unique_user()) {
1449 igvn->add_users_to_worklist( n );
1450 } else if (n->outcnt() <= 2 && n->is_Store()) {
1451 // Push store's uses on worklist to enable folding optimization for
1452 // store/store and store/load to the same address.
1453 // The restriction (outcnt() <= 2) is the same as in set_req_X()
1454 // and remove_globally_dead_node().
1455 igvn->add_users_to_worklist( n );
1456 } else if (dead->is_data_proj_of_pure_function(n)) {
1457 igvn->_worklist.push(n);
1458 } else {
1459 BarrierSet::barrier_set()->barrier_set_c2()->enqueue_useful_gc_barrier(igvn, n);
1460 }
1461 }
1462 }
1463 igvn->C->remove_useless_node(dead);
1464 } // (dead->outcnt() == 0)
1465 } // while (nstack.size() > 0) for outputs
1466 return;
1467 }
1468
1469 //------------------------------remove_dead_region-----------------------------
1470 bool Node::remove_dead_region(PhaseGVN *phase, bool can_reshape) {
1471 Node *n = in(0);
1472 if( !n ) return false;
1473 // Lost control into this guy? I.e., it became unreachable?
1474 // Aggressively kill all unreachable code.
1475 if (can_reshape && n->is_top()) {
1476 kill_dead_code(this, phase->is_IterGVN());
1477 return false; // Node is dead.
1478 }
1479
1480 if( n->is_Region() && n->as_Region()->is_copy() ) {
1481 Node *m = n->nonnull_req();
1482 set_req(0, m);
1483 return true;
1484 }
1485 return false;
1486 }
1487
1488 //------------------------------hash-------------------------------------------
1489 // Hash function over Nodes.
1490 uint Node::hash() const {
1491 uint sum = 0;
1492 for( uint i=0; i<_cnt; i++ ) // Add in all inputs
1493 sum = (sum<<1)-(uintptr_t)in(i); // Ignore embedded nulls
1494 return (sum>>2) + _cnt + Opcode();
1495 }
1496
1497 //------------------------------cmp--------------------------------------------
1498 // Compare special parts of simple Nodes
1499 bool Node::cmp( const Node &n ) const {
1500 return true; // Must be same
1501 }
1502
1503 //------------------------------rematerialize-----------------------------------
1504 // Should we clone rather than spill this instruction?
1505 bool Node::rematerialize() const {
1506 if ( is_Mach() )
1507 return this->as_Mach()->rematerialize();
1508 else
1509 return (_flags & Flag_rematerialize) != 0;
1510 }
1511
1512 //------------------------------needs_anti_dependence_check---------------------
1513 // Nodes which use memory without consuming it, hence need antidependences.
1514 bool Node::needs_anti_dependence_check() const {
1515 if (req() < 2 || (_flags & Flag_needs_anti_dependence_check) == 0) {
1516 return false;
1517 }
1518 return in(1)->bottom_type()->has_memory();
1519 }
1520
1521 // Get an integer constant from a ConNode (or CastIINode).
1522 // Return a default value if there is no apparent constant here.
1523 const TypeInt* Node::find_int_type() const {
1524 if (this->is_Type()) {
1525 return this->as_Type()->type()->isa_int();
1526 } else if (this->is_Con()) {
1527 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1528 return this->bottom_type()->isa_int();
1529 }
1530 return nullptr;
1531 }
1532
1533 const TypeInteger* Node::find_integer_type(BasicType bt) const {
1534 if (this->is_Type()) {
1535 return this->as_Type()->type()->isa_integer(bt);
1536 } else if (this->is_Con()) {
1537 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1538 return this->bottom_type()->isa_integer(bt);
1539 }
1540 return nullptr;
1541 }
1542
1543 // Get a pointer constant from a ConstNode.
1544 // Returns the constant if it is a pointer ConstNode
1545 intptr_t Node::get_ptr() const {
1546 assert( Opcode() == Op_ConP, "" );
1547 return ((ConPNode*)this)->type()->is_ptr()->get_con();
1548 }
1549
1550 // Get a narrow oop constant from a ConNNode.
1551 intptr_t Node::get_narrowcon() const {
1552 assert( Opcode() == Op_ConN, "" );
1553 return ((ConNNode*)this)->type()->is_narrowoop()->get_con();
1554 }
1555
1556 // Get a long constant from a ConNode.
1557 // Return a default value if there is no apparent constant here.
1558 const TypeLong* Node::find_long_type() const {
1559 if (this->is_Type()) {
1560 return this->as_Type()->type()->isa_long();
1561 } else if (this->is_Con()) {
1562 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1563 return this->bottom_type()->isa_long();
1564 }
1565 return nullptr;
1566 }
1567
1568
1569 /**
1570 * Return a ptr type for nodes which should have it.
1571 */
1572 const TypePtr* Node::get_ptr_type() const {
1573 const TypePtr* tp = this->bottom_type()->make_ptr();
1574 #ifdef ASSERT
1575 if (tp == nullptr) {
1576 this->dump(1);
1577 assert((tp != nullptr), "unexpected node type");
1578 }
1579 #endif
1580 return tp;
1581 }
1582
1583 // Get a double constant from a ConstNode.
1584 // Returns the constant if it is a double ConstNode
1585 jdouble Node::getd() const {
1586 assert( Opcode() == Op_ConD, "" );
1587 return ((ConDNode*)this)->type()->is_double_constant()->getd();
1588 }
1589
1590 // Get a float constant from a ConstNode.
1591 // Returns the constant if it is a float ConstNode
1592 jfloat Node::getf() const {
1593 assert( Opcode() == Op_ConF, "" );
1594 return ((ConFNode*)this)->type()->is_float_constant()->getf();
1595 }
1596
1597 // Get a half float constant from a ConstNode.
1598 // Returns the constant if it is a float ConstNode
1599 jshort Node::geth() const {
1600 assert( Opcode() == Op_ConH, "" );
1601 return ((ConHNode*)this)->type()->is_half_float_constant()->geth();
1602 }
1603
1604 #ifndef PRODUCT
1605
1606 // Call this from debugger:
1607 Node* old_root() {
1608 Matcher* matcher = Compile::current()->matcher();
1609 if (matcher != nullptr) {
1610 Node* new_root = Compile::current()->root();
1611 Node* old_root = matcher->find_old_node(new_root);
1612 if (old_root != nullptr) {
1613 return old_root;
1614 }
1615 }
1616 tty->print("old_root: not found.\n");
1617 return nullptr;
1618 }
1619
1620 // BFS traverse all reachable nodes from start, call callback on them
1621 template <typename Callback>
1622 void visit_nodes(Node* start, Callback callback, bool traverse_output, bool only_ctrl) {
1623 Unique_Mixed_Node_List worklist;
1624 worklist.add(start);
1625 for (uint i = 0; i < worklist.size(); i++) {
1626 Node* n = worklist[i];
1627 callback(n);
1628 for (uint i = 0; i < n->len(); i++) {
1629 if (!only_ctrl || n->is_Region() || (n->Opcode() == Op_Root) || (i == TypeFunc::Control)) {
1630 // If only_ctrl is set: Add regions, the root node, or control inputs only
1631 worklist.add(n->in(i));
1632 }
1633 }
1634 if (traverse_output && !only_ctrl) {
1635 for (uint i = 0; i < n->outcnt(); i++) {
1636 worklist.add(n->raw_out(i));
1637 }
1638 }
1639 }
1640 }
1641
1642 // BFS traverse from start, return node with idx
1643 static Node* find_node_by_idx(Node* start, uint idx, bool traverse_output, bool only_ctrl) {
1644 ResourceMark rm;
1645 Node* result = nullptr;
1646 auto callback = [&] (Node* n) {
1647 if (n->_idx == idx) {
1648 if (result != nullptr) {
1649 tty->print("find_node_by_idx: " INTPTR_FORMAT " and " INTPTR_FORMAT " both have idx==%d\n",
1650 (uintptr_t)result, (uintptr_t)n, idx);
1651 }
1652 result = n;
1653 }
1654 };
1655 visit_nodes(start, callback, traverse_output, only_ctrl);
1656 return result;
1657 }
1658
1659 static int node_idx_cmp(const Node** n1, const Node** n2) {
1660 return (*n1)->_idx - (*n2)->_idx;
1661 }
1662
1663 static void find_nodes_by_name(Node* start, const char* name) {
1664 ResourceMark rm;
1665 GrowableArray<const Node*> ns;
1666 auto callback = [&] (const Node* n) {
1667 if (StringUtils::is_star_match(name, n->Name())) {
1668 ns.push(n);
1669 }
1670 };
1671 visit_nodes(start, callback, true, false);
1672 ns.sort(node_idx_cmp);
1673 for (int i = 0; i < ns.length(); i++) {
1674 ns.at(i)->dump();
1675 }
1676 }
1677
1678 static void find_nodes_by_dump(Node* start, const char* pattern) {
1679 ResourceMark rm;
1680 GrowableArray<const Node*> ns;
1681 auto callback = [&] (const Node* n) {
1682 stringStream stream;
1683 n->dump("", false, &stream);
1684 if (StringUtils::is_star_match(pattern, stream.base())) {
1685 ns.push(n);
1686 }
1687 };
1688 visit_nodes(start, callback, true, false);
1689 ns.sort(node_idx_cmp);
1690 for (int i = 0; i < ns.length(); i++) {
1691 ns.at(i)->dump();
1692 }
1693 }
1694
1695 // call from debugger: find node with name pattern in new/current graph
1696 // name can contain "*" in match pattern to match any characters
1697 // the matching is case insensitive
1698 void find_nodes_by_name(const char* name) {
1699 Node* root = Compile::current()->root();
1700 find_nodes_by_name(root, name);
1701 }
1702
1703 // call from debugger: find node with name pattern in old graph
1704 // name can contain "*" in match pattern to match any characters
1705 // the matching is case insensitive
1706 void find_old_nodes_by_name(const char* name) {
1707 Node* root = old_root();
1708 find_nodes_by_name(root, name);
1709 }
1710
1711 // call from debugger: find node with dump pattern in new/current graph
1712 // can contain "*" in match pattern to match any characters
1713 // the matching is case insensitive
1714 void find_nodes_by_dump(const char* pattern) {
1715 Node* root = Compile::current()->root();
1716 find_nodes_by_dump(root, pattern);
1717 }
1718
1719 // call from debugger: find node with name pattern in old graph
1720 // can contain "*" in match pattern to match any characters
1721 // the matching is case insensitive
1722 void find_old_nodes_by_dump(const char* pattern) {
1723 Node* root = old_root();
1724 find_nodes_by_dump(root, pattern);
1725 }
1726
1727 // Call this from debugger, search in same graph as n:
1728 Node* find_node(Node* n, const int idx) {
1729 return n->find(idx);
1730 }
1731
1732 // Call this from debugger, search in new nodes:
1733 Node* find_node(const int idx) {
1734 return Compile::current()->root()->find(idx);
1735 }
1736
1737 // Call this from debugger, search in old nodes:
1738 Node* find_old_node(const int idx) {
1739 Node* root = old_root();
1740 return (root == nullptr) ? nullptr : root->find(idx);
1741 }
1742
1743 // Call this from debugger, search in same graph as n:
1744 Node* find_ctrl(Node* n, const int idx) {
1745 return n->find_ctrl(idx);
1746 }
1747
1748 // Call this from debugger, search in new nodes:
1749 Node* find_ctrl(const int idx) {
1750 return Compile::current()->root()->find_ctrl(idx);
1751 }
1752
1753 // Call this from debugger, search in old nodes:
1754 Node* find_old_ctrl(const int idx) {
1755 Node* root = old_root();
1756 return (root == nullptr) ? nullptr : root->find_ctrl(idx);
1757 }
1758
1759 //------------------------------find_ctrl--------------------------------------
1760 // Find an ancestor to this node in the control history with given _idx
1761 Node* Node::find_ctrl(int idx) {
1762 return find(idx, true);
1763 }
1764
1765 //------------------------------find-------------------------------------------
1766 // Tries to find the node with the index |idx| starting from this node. If idx is negative,
1767 // the search also includes forward (out) edges. Returns null if not found.
1768 // If only_ctrl is set, the search will only be done on control nodes. Returns null if
1769 // not found or if the node to be found is not a control node (search will not find it).
1770 Node* Node::find(const int idx, bool only_ctrl) {
1771 ResourceMark rm;
1772 return find_node_by_idx(this, abs(idx), (idx < 0), only_ctrl);
1773 }
1774
1775 class PrintBFS {
1776 public:
1777 PrintBFS(const Node* start, const int max_distance, const Node* target, const char* options, outputStream* st)
1778 : _start(start), _max_distance(max_distance), _target(target), _options(options), _output(st),
1779 _dcc(this), _info_uid(cmpkey, hashkey) {}
1780
1781 void run();
1782 private:
1783 // pipeline steps
1784 bool configure();
1785 void collect();
1786 void select();
1787 void select_all();
1788 void select_all_paths();
1789 void select_shortest_path();
1790 void sort();
1791 void print();
1792
1793 // inputs
1794 const Node* _start;
1795 const int _max_distance;
1796 const Node* _target;
1797 const char* _options;
1798 outputStream* _output;
1799
1800 // options
1801 bool _traverse_inputs = false;
1802 bool _traverse_outputs = false;
1803 struct Filter {
1804 bool _control = false;
1805 bool _memory = false;
1806 bool _data = false;
1807 bool _mixed = false;
1808 bool _other = false;
1809 bool is_empty() const {
1810 return !(_control || _memory || _data || _mixed || _other);
1811 }
1812 void set_all() {
1813 _control = true;
1814 _memory = true;
1815 _data = true;
1816 _mixed = true;
1817 _other = true;
1818 }
1819 // Check if the filter accepts the node. Go by the type categories, but also all CFG nodes
1820 // are considered to have control.
1821 bool accepts(const Node* n) {
1822 const Type* t = n->bottom_type();
1823 return ( _data && t->has_category(Type::Category::Data) ) ||
1824 ( _memory && t->has_category(Type::Category::Memory) ) ||
1825 ( _mixed && t->has_category(Type::Category::Mixed) ) ||
1826 ( _control && (t->has_category(Type::Category::Control) || n->is_CFG()) ) ||
1827 ( _other && t->has_category(Type::Category::Other) );
1828 }
1829 };
1830 Filter _filter_visit;
1831 Filter _filter_boundary;
1832 bool _sort_idx = false;
1833 bool _all_paths = false;
1834 bool _use_color = false;
1835 bool _print_blocks = false;
1836 bool _print_old = false;
1837 bool _dump_only = false;
1838 bool _print_igv = false;
1839
1840 void print_options_help(bool print_examples);
1841 bool parse_options();
1842
1843 public:
1844 class DumpConfigColored : public Node::DumpConfig {
1845 public:
1846 DumpConfigColored(PrintBFS* bfs) : _bfs(bfs) {};
1847 virtual void pre_dump(outputStream* st, const Node* n);
1848 virtual void post_dump(outputStream* st);
1849 private:
1850 PrintBFS* _bfs;
1851 };
1852 private:
1853 DumpConfigColored _dcc;
1854
1855 // node info
1856 static Node* old_node(const Node* n); // mach node -> prior IR node
1857 void print_node_idx(const Node* n);
1858 void print_block_id(const Block* b);
1859 void print_node_block(const Node* n); // _pre_order, head idx, _idom, _dom_depth
1860
1861 // traversal data structures
1862 GrowableArray<const Node*> _worklist; // BFS queue
1863 void maybe_traverse(const Node* src, const Node* dst);
1864
1865 // node info annotation
1866 class Info {
1867 public:
1868 Info() : Info(nullptr, 0) {};
1869 Info(const Node* node, int distance)
1870 : _node(node), _distance_from_start(distance) {};
1871 const Node* node() const { return _node; };
1872 int distance() const { return _distance_from_start; };
1873 int distance_from_target() const { return _distance_from_target; }
1874 void set_distance_from_target(int d) { _distance_from_target = d; }
1875 GrowableArray<const Node*> edge_bwd; // pointing toward _start
1876 bool is_marked() const { return _mark; } // marked to keep during select
1877 void set_mark() { _mark = true; }
1878 private:
1879 const Node* _node;
1880 int _distance_from_start; // distance from _start
1881 int _distance_from_target = 0; // distance from _target if _all_paths
1882 bool _mark = false;
1883 };
1884 Dict _info_uid; // Node -> uid
1885 GrowableArray<Info> _info; // uid -> info
1886
1887 Info* find_info(const Node* n) {
1888 size_t uid = (size_t)_info_uid[n];
1889 if (uid == 0) {
1890 return nullptr;
1891 }
1892 return &_info.at((int)uid);
1893 }
1894
1895 void make_info(const Node* node, const int distance) {
1896 assert(find_info(node) == nullptr, "node does not yet have info");
1897 size_t uid = _info.length() + 1;
1898 _info_uid.Insert((void*)node, (void*)uid);
1899 _info.at_put_grow((int)uid, Info(node, distance));
1900 assert(find_info(node)->node() == node, "stored correct node");
1901 };
1902
1903 // filled by sort, printed by print
1904 GrowableArray<const Node*> _print_list;
1905
1906 // print header + node table
1907 void print_header() const;
1908 void print_node(const Node* n);
1909 };
1910
1911 void PrintBFS::run() {
1912 if (!configure()) {
1913 return;
1914 }
1915 collect();
1916 select();
1917 sort();
1918 print();
1919 }
1920
1921 // set up configuration for BFS and print
1922 bool PrintBFS::configure() {
1923 if (_max_distance < 0) {
1924 _output->print_cr("dump_bfs: max_distance must be non-negative!");
1925 return false;
1926 }
1927 return parse_options();
1928 }
1929
1930 // BFS traverse according to configuration, fill worklist and info
1931 void PrintBFS::collect() {
1932 maybe_traverse(_start, _start);
1933 int pos = 0;
1934 while (pos < _worklist.length()) {
1935 const Node* n = _worklist.at(pos++); // next node to traverse
1936 Info* info = find_info(n);
1937 if (!_filter_visit.accepts(n) && n != _start) {
1938 continue; // we hit boundary, do not traverse further
1939 }
1940 if (n != _start && n->is_Root()) {
1941 continue; // traversing through root node would lead to unrelated nodes
1942 }
1943 if (_traverse_inputs && _max_distance > info->distance()) {
1944 for (uint i = 0; i < n->req(); i++) {
1945 maybe_traverse(n, n->in(i));
1946 }
1947 }
1948 if (_traverse_outputs && _max_distance > info->distance()) {
1949 for (uint i = 0; i < n->outcnt(); i++) {
1950 maybe_traverse(n, n->raw_out(i));
1951 }
1952 }
1953 }
1954 }
1955
1956 // go through work list, mark those that we want to print
1957 void PrintBFS::select() {
1958 if (_target == nullptr ) {
1959 select_all();
1960 } else {
1961 if (find_info(_target) == nullptr) {
1962 _output->print_cr("Could not find target in BFS.");
1963 return;
1964 }
1965 if (_all_paths) {
1966 select_all_paths();
1967 } else {
1968 select_shortest_path();
1969 }
1970 }
1971 }
1972
1973 // take all nodes from BFS
1974 void PrintBFS::select_all() {
1975 for (int i = 0; i < _worklist.length(); i++) {
1976 const Node* n = _worklist.at(i);
1977 Info* info = find_info(n);
1978 info->set_mark();
1979 }
1980 }
1981
1982 // traverse backward from target, along edges found in BFS
1983 void PrintBFS::select_all_paths() {
1984 int pos = 0;
1985 GrowableArray<const Node*> backtrace;
1986 // start from target
1987 backtrace.push(_target);
1988 find_info(_target)->set_mark();
1989 // traverse backward
1990 while (pos < backtrace.length()) {
1991 const Node* n = backtrace.at(pos++);
1992 Info* info = find_info(n);
1993 for (int i = 0; i < info->edge_bwd.length(); i++) {
1994 // all backward edges
1995 const Node* back = info->edge_bwd.at(i);
1996 Info* back_info = find_info(back);
1997 if (!back_info->is_marked()) {
1998 // not yet found this on way back.
1999 back_info->set_distance_from_target(info->distance_from_target() + 1);
2000 if (back_info->distance_from_target() + back_info->distance() <= _max_distance) {
2001 // total distance is small enough
2002 back_info->set_mark();
2003 backtrace.push(back);
2004 }
2005 }
2006 }
2007 }
2008 }
2009
2010 void PrintBFS::select_shortest_path() {
2011 const Node* current = _target;
2012 while (true) {
2013 Info* info = find_info(current);
2014 info->set_mark();
2015 if (current == _start) {
2016 break;
2017 }
2018 // first edge -> leads us one step closer to _start
2019 current = info->edge_bwd.at(0);
2020 }
2021 }
2022
2023 // go through worklist in desired order, put the marked ones in print list
2024 void PrintBFS::sort() {
2025 if (_traverse_inputs && !_traverse_outputs) {
2026 // reverse order
2027 for (int i = _worklist.length() - 1; i >= 0; i--) {
2028 const Node* n = _worklist.at(i);
2029 Info* info = find_info(n);
2030 if (info->is_marked()) {
2031 _print_list.push(n);
2032 }
2033 }
2034 } else {
2035 // same order as worklist
2036 for (int i = 0; i < _worklist.length(); i++) {
2037 const Node* n = _worklist.at(i);
2038 Info* info = find_info(n);
2039 if (info->is_marked()) {
2040 _print_list.push(n);
2041 }
2042 }
2043 }
2044 if (_sort_idx) {
2045 _print_list.sort(node_idx_cmp);
2046 }
2047 }
2048
2049 // go through printlist and print
2050 void PrintBFS::print() {
2051 if (_print_list.length() > 0 ) {
2052 print_header();
2053 for (int i = 0; i < _print_list.length(); i++) {
2054 const Node* n = _print_list.at(i);
2055 print_node(n);
2056 }
2057 if (_print_igv) {
2058 Compile* C = Compile::current();
2059 C->init_igv();
2060 C->igv_print_graph_to_network("PrintBFS", (Node*) C->root(), _print_list);
2061 }
2062 } else {
2063 _output->print_cr("No nodes to print.");
2064 }
2065 }
2066
2067 void PrintBFS::print_options_help(bool print_examples) {
2068 _output->print_cr("Usage: node->dump_bfs(int max_distance, Node* target, char* options)");
2069 _output->print_cr("");
2070 _output->print_cr("Use cases:");
2071 _output->print_cr(" BFS traversal: no target required");
2072 _output->print_cr(" shortest path: set target");
2073 _output->print_cr(" all paths: set target and put 'A' in options");
2074 _output->print_cr(" detect loop: subcase of all paths, have start==target");
2075 _output->print_cr("");
2076 _output->print_cr("Arguments:");
2077 _output->print_cr(" this/start: staring point of BFS");
2078 _output->print_cr(" target:");
2079 _output->print_cr(" if null: simple BFS");
2080 _output->print_cr(" else: shortest path or all paths between this/start and target");
2081 _output->print_cr(" options:");
2082 _output->print_cr(" if null: same as \"cdmox@B\"");
2083 _output->print_cr(" else: use combination of following characters");
2084 _output->print_cr(" h: display this help info");
2085 _output->print_cr(" H: display this help info, with examples");
2086 _output->print_cr(" +: traverse in-edges (on if neither + nor -)");
2087 _output->print_cr(" -: traverse out-edges");
2088 _output->print_cr(" c: visit control nodes");
2089 _output->print_cr(" d: visit data nodes");
2090 _output->print_cr(" m: visit memory nodes");
2091 _output->print_cr(" o: visit other nodes");
2092 _output->print_cr(" x: visit mixed nodes");
2093 _output->print_cr(" C: boundary control nodes");
2094 _output->print_cr(" D: boundary data nodes");
2095 _output->print_cr(" M: boundary memory nodes");
2096 _output->print_cr(" O: boundary other nodes");
2097 _output->print_cr(" X: boundary mixed nodes");
2098 _output->print_cr(" #: display node category in color (not supported in all terminals)");
2099 _output->print_cr(" S: sort displayed nodes by node idx");
2100 _output->print_cr(" A: all paths (not just shortest path to target)");
2101 _output->print_cr(" @: print old nodes - before matching (if available)");
2102 _output->print_cr(" B: print scheduling blocks (if available)");
2103 _output->print_cr(" $: dump only, no header, no other columns");
2104 _output->print_cr(" !: show nodes on IGV (sent over network stream)");
2105 _output->print_cr("");
2106 _output->print_cr("recursively follow edges to nodes with permitted visit types,");
2107 _output->print_cr("on the boundary additionally display nodes allowed in boundary types");
2108 _output->print_cr("Note: the categories can be overlapping. For example a mixed node");
2109 _output->print_cr(" can contain control and memory output. Some from the other");
2110 _output->print_cr(" category are also control (Halt, Return, etc).");
2111 _output->print_cr("");
2112 _output->print_cr("output columns:");
2113 _output->print_cr(" dist: BFS distance to this/start");
2114 _output->print_cr(" apd: all paths distance (d_outputart + d_target)");
2115 _output->print_cr(" block: block identifier, based on _pre_order");
2116 _output->print_cr(" head: first node in block");
2117 _output->print_cr(" idom: head node of idom block");
2118 _output->print_cr(" depth: depth of block (_dom_depth)");
2119 _output->print_cr(" old: old IR node - before matching");
2120 _output->print_cr(" dump: node->dump()");
2121 _output->print_cr("");
2122 _output->print_cr("Note: if none of the \"cmdxo\" characters are in the options string");
2123 _output->print_cr(" then we set all of them.");
2124 _output->print_cr(" This allows for short strings like \"#\" for colored input traversal");
2125 _output->print_cr(" or \"-#\" for colored output traversal.");
2126 if (print_examples) {
2127 _output->print_cr("");
2128 _output->print_cr("Examples:");
2129 _output->print_cr(" if->dump_bfs(10, 0, \"+cxo\")");
2130 _output->print_cr(" starting at some if node, traverse inputs recursively");
2131 _output->print_cr(" only along control (mixed and other can also be control)");
2132 _output->print_cr(" phi->dump_bfs(5, 0, \"-dxo\")");
2133 _output->print_cr(" starting at phi node, traverse outputs recursively");
2134 _output->print_cr(" only along data (mixed and other can also have data flow)");
2135 _output->print_cr(" find_node(385)->dump_bfs(3, 0, \"cdmox+#@B\")");
2136 _output->print_cr(" find inputs of node 385, up to 3 nodes up (+)");
2137 _output->print_cr(" traverse all nodes (cdmox), use colors (#)");
2138 _output->print_cr(" display old nodes and blocks, if they exist");
2139 _output->print_cr(" useful call to start with");
2140 _output->print_cr(" find_node(102)->dump_bfs(10, 0, \"dCDMOX-\")");
2141 _output->print_cr(" find non-data dependencies of a data node");
2142 _output->print_cr(" follow data node outputs until we find another category");
2143 _output->print_cr(" node as the boundary");
2144 _output->print_cr(" x->dump_bfs(10, y, 0)");
2145 _output->print_cr(" find shortest path from x to y, along any edge or node");
2146 _output->print_cr(" will not find a path if it is longer than 10");
2147 _output->print_cr(" useful to find how x and y are related");
2148 _output->print_cr(" find_node(741)->dump_bfs(20, find_node(746), \"c+\")");
2149 _output->print_cr(" find shortest control path between two nodes");
2150 _output->print_cr(" find_node(741)->dump_bfs(8, find_node(746), \"cdmox+A\")");
2151 _output->print_cr(" find all paths (A) between two nodes of length at most 8");
2152 _output->print_cr(" find_node(741)->dump_bfs(7, find_node(741), \"c+A\")");
2153 _output->print_cr(" find all control loops for this node");
2154 }
2155 }
2156
2157 bool PrintBFS::parse_options() {
2158 if (_options == nullptr) {
2159 _options = "cdmox@B"; // default options
2160 }
2161 size_t len = strlen(_options);
2162 for (size_t i = 0; i < len; i++) {
2163 switch (_options[i]) {
2164 case '+':
2165 _traverse_inputs = true;
2166 break;
2167 case '-':
2168 _traverse_outputs = true;
2169 break;
2170 case 'c':
2171 _filter_visit._control = true;
2172 break;
2173 case 'm':
2174 _filter_visit._memory = true;
2175 break;
2176 case 'd':
2177 _filter_visit._data = true;
2178 break;
2179 case 'x':
2180 _filter_visit._mixed = true;
2181 break;
2182 case 'o':
2183 _filter_visit._other = true;
2184 break;
2185 case 'C':
2186 _filter_boundary._control = true;
2187 break;
2188 case 'M':
2189 _filter_boundary._memory = true;
2190 break;
2191 case 'D':
2192 _filter_boundary._data = true;
2193 break;
2194 case 'X':
2195 _filter_boundary._mixed = true;
2196 break;
2197 case 'O':
2198 _filter_boundary._other = true;
2199 break;
2200 case 'S':
2201 _sort_idx = true;
2202 break;
2203 case 'A':
2204 _all_paths = true;
2205 break;
2206 case '#':
2207 _use_color = true;
2208 break;
2209 case 'B':
2210 _print_blocks = true;
2211 break;
2212 case '@':
2213 _print_old = true;
2214 break;
2215 case '$':
2216 _dump_only = true;
2217 break;
2218 case '!':
2219 _print_igv = true;
2220 break;
2221 case 'h':
2222 print_options_help(false);
2223 return false;
2224 case 'H':
2225 print_options_help(true);
2226 return false;
2227 default:
2228 _output->print_cr("dump_bfs: Unrecognized option \'%c\'", _options[i]);
2229 _output->print_cr("for help, run: find_node(0)->dump_bfs(0,0,\"H\")");
2230 return false;
2231 }
2232 }
2233 if (!_traverse_inputs && !_traverse_outputs) {
2234 _traverse_inputs = true;
2235 }
2236 if (_filter_visit.is_empty()) {
2237 _filter_visit.set_all();
2238 }
2239 Compile* C = Compile::current();
2240 _print_old &= (C->matcher() != nullptr); // only show old if there are new
2241 _print_blocks &= (C->cfg() != nullptr); // only show blocks if available
2242 return true;
2243 }
2244
2245 void PrintBFS::DumpConfigColored::pre_dump(outputStream* st, const Node* n) {
2246 if (!_bfs->_use_color) {
2247 return;
2248 }
2249 Info* info = _bfs->find_info(n);
2250 if (info == nullptr || !info->is_marked()) {
2251 return;
2252 }
2253
2254 const Type* t = n->bottom_type();
2255 switch (t->category()) {
2256 case Type::Category::Data:
2257 st->print("\u001b[34m");
2258 break;
2259 case Type::Category::Memory:
2260 st->print("\u001b[32m");
2261 break;
2262 case Type::Category::Mixed:
2263 st->print("\u001b[35m");
2264 break;
2265 case Type::Category::Control:
2266 st->print("\u001b[31m");
2267 break;
2268 case Type::Category::Other:
2269 st->print("\u001b[33m");
2270 break;
2271 case Type::Category::Undef:
2272 n->dump();
2273 assert(false, "category undef ??");
2274 break;
2275 default:
2276 n->dump();
2277 assert(false, "not covered");
2278 break;
2279 }
2280 }
2281
2282 void PrintBFS::DumpConfigColored::post_dump(outputStream* st) {
2283 if (!_bfs->_use_color) {
2284 return;
2285 }
2286 st->print("\u001b[0m"); // white
2287 }
2288
2289 Node* PrintBFS::old_node(const Node* n) {
2290 Compile* C = Compile::current();
2291 if (C->matcher() == nullptr || !C->node_arena()->contains(n)) {
2292 return (Node*)nullptr;
2293 } else {
2294 return C->matcher()->find_old_node(n);
2295 }
2296 }
2297
2298 void PrintBFS::print_node_idx(const Node* n) {
2299 Compile* C = Compile::current();
2300 char buf[30];
2301 if (n == nullptr) {
2302 os::snprintf_checked(buf, sizeof(buf), "_"); // null
2303 } else if (C->node_arena()->contains(n)) {
2304 os::snprintf_checked(buf, sizeof(buf), "%d", n->_idx); // new node
2305 } else {
2306 os::snprintf_checked(buf, sizeof(buf), "o%d", n->_idx); // old node
2307 }
2308 _output->print("%6s", buf);
2309 }
2310
2311 void PrintBFS::print_block_id(const Block* b) {
2312 Compile* C = Compile::current();
2313 char buf[30];
2314 os::snprintf_checked(buf, sizeof(buf), "B%d", b->_pre_order);
2315 _output->print("%7s", buf);
2316 }
2317
2318 void PrintBFS::print_node_block(const Node* n) {
2319 Compile* C = Compile::current();
2320 Block* b = C->node_arena()->contains(n)
2321 ? C->cfg()->get_block_for_node(n)
2322 : nullptr; // guard against old nodes
2323 if (b == nullptr) {
2324 _output->print(" _"); // Block
2325 _output->print(" _"); // head
2326 _output->print(" _"); // idom
2327 _output->print(" _"); // depth
2328 } else {
2329 print_block_id(b);
2330 print_node_idx(b->head());
2331 if (b->_idom) {
2332 print_node_idx(b->_idom->head());
2333 } else {
2334 _output->print(" _"); // idom
2335 }
2336 _output->print("%6d ", b->_dom_depth);
2337 }
2338 }
2339
2340 // filter, and add to worklist, add info, note traversal edges
2341 void PrintBFS::maybe_traverse(const Node* src, const Node* dst) {
2342 if (dst != nullptr &&
2343 (_filter_visit.accepts(dst) ||
2344 _filter_boundary.accepts(dst) ||
2345 dst == _start)) { // correct category or start?
2346 if (find_info(dst) == nullptr) {
2347 // never visited - set up info
2348 _worklist.push(dst);
2349 int d = 0;
2350 if (dst != _start) {
2351 d = find_info(src)->distance() + 1;
2352 }
2353 make_info(dst, d);
2354 }
2355 if (src != dst) {
2356 // traversal edges useful during select
2357 find_info(dst)->edge_bwd.push(src);
2358 }
2359 }
2360 }
2361
2362 void PrintBFS::print_header() const {
2363 if (_dump_only) {
2364 return; // no header in dump only mode
2365 }
2366 _output->print("dist"); // distance
2367 if (_all_paths) {
2368 _output->print(" apd"); // all paths distance
2369 }
2370 if (_print_blocks) {
2371 _output->print(" [block head idom depth]"); // block
2372 }
2373 if (_print_old) {
2374 _output->print(" old"); // old node
2375 }
2376 _output->print(" dump\n"); // node dump
2377 _output->print_cr("---------------------------------------------");
2378 }
2379
2380 void PrintBFS::print_node(const Node* n) {
2381 if (_dump_only) {
2382 n->dump("\n", false, _output, &_dcc);
2383 return;
2384 }
2385 _output->print("%4d", find_info(n)->distance());// distance
2386 if (_all_paths) {
2387 Info* info = find_info(n);
2388 int apd = info->distance() + info->distance_from_target();
2389 _output->print("%4d", apd); // all paths distance
2390 }
2391 if (_print_blocks) {
2392 print_node_block(n); // block
2393 }
2394 if (_print_old) {
2395 print_node_idx(old_node(n)); // old node
2396 }
2397 _output->print(" ");
2398 n->dump("\n", false, _output, &_dcc); // node dump
2399 }
2400
2401 //------------------------------dump_bfs--------------------------------------
2402 // Call this from debugger
2403 // Useful for BFS traversal, shortest path, all path, loop detection, etc
2404 // Designed to be more readable, and provide additional info
2405 // To find all options, run:
2406 // find_node(0)->dump_bfs(0,0,"H")
2407 void Node::dump_bfs(const int max_distance, Node* target, const char* options) const {
2408 dump_bfs(max_distance, target, options, tty);
2409 }
2410
2411 // Used to dump to stream.
2412 void Node::dump_bfs(const int max_distance, Node* target, const char* options, outputStream* st) const {
2413 PrintBFS bfs(this, max_distance, target, options, st);
2414 bfs.run();
2415 }
2416
2417 // Call this from debugger, with default arguments
2418 void Node::dump_bfs(const int max_distance) const {
2419 dump_bfs(max_distance, nullptr, nullptr);
2420 }
2421
2422 // -----------------------------dump_idx---------------------------------------
2423 void Node::dump_idx(bool align, outputStream* st, DumpConfig* dc) const {
2424 if (dc != nullptr) {
2425 dc->pre_dump(st, this);
2426 }
2427 Compile* C = Compile::current();
2428 bool is_new = C->node_arena()->contains(this);
2429 if (align) { // print prefix empty spaces$
2430 // +1 for leading digit, +1 for "o"
2431 uint max_width = (C->unique() == 0 ? 0 : static_cast<uint>(log10(static_cast<double>(C->unique())))) + 2;
2432 // +1 for leading digit, maybe +1 for "o"
2433 uint width = (_idx == 0 ? 0 : static_cast<uint>(log10(static_cast<double>(_idx)))) + 1 + (is_new ? 0 : 1);
2434 while (max_width > width) {
2435 st->print(" ");
2436 width++;
2437 }
2438 }
2439 if (!is_new) {
2440 st->print("o");
2441 }
2442 st->print("%d", _idx);
2443 if (dc != nullptr) {
2444 dc->post_dump(st);
2445 }
2446 }
2447
2448 // -----------------------------dump_name--------------------------------------
2449 void Node::dump_name(outputStream* st, DumpConfig* dc) const {
2450 if (dc != nullptr) {
2451 dc->pre_dump(st, this);
2452 }
2453 st->print("%s", Name());
2454 if (dc != nullptr) {
2455 dc->post_dump(st);
2456 }
2457 }
2458
2459 // -----------------------------Name-------------------------------------------
2460 extern const char *NodeClassNames[];
2461 const char *Node::Name() const { return NodeClassNames[Opcode()]; }
2462
2463 static bool is_disconnected(const Node* n) {
2464 for (uint i = 0; i < n->req(); i++) {
2465 if (n->in(i) != nullptr) return false;
2466 }
2467 return true;
2468 }
2469
2470 #ifdef ASSERT
2471 void Node::dump_orig(outputStream *st, bool print_key) const {
2472 Compile* C = Compile::current();
2473 Node* orig = _debug_orig;
2474 if (not_a_node(orig)) orig = nullptr;
2475 if (orig != nullptr && !C->node_arena()->contains(orig)) orig = nullptr;
2476 if (orig == nullptr) return;
2477 if (print_key) {
2478 st->print(" !orig=");
2479 }
2480 Node* fast = orig->debug_orig(); // tortoise & hare algorithm to detect loops
2481 if (not_a_node(fast)) fast = nullptr;
2482 while (orig != nullptr) {
2483 bool discon = is_disconnected(orig); // if discon, print [123] else 123
2484 if (discon) st->print("[");
2485 if (!Compile::current()->node_arena()->contains(orig))
2486 st->print("o");
2487 st->print("%d", orig->_idx);
2488 if (discon) st->print("]");
2489 orig = orig->debug_orig();
2490 if (not_a_node(orig)) orig = nullptr;
2491 if (orig != nullptr && !C->node_arena()->contains(orig)) orig = nullptr;
2492 if (orig != nullptr) st->print(",");
2493 if (fast != nullptr) {
2494 // Step fast twice for each single step of orig:
2495 fast = fast->debug_orig();
2496 if (not_a_node(fast)) fast = nullptr;
2497 if (fast != nullptr && fast != orig) {
2498 fast = fast->debug_orig();
2499 if (not_a_node(fast)) fast = nullptr;
2500 }
2501 if (fast == orig) {
2502 st->print("...");
2503 break;
2504 }
2505 }
2506 }
2507 }
2508
2509 void Node::set_debug_orig(Node* orig) {
2510 _debug_orig = orig;
2511 if (BreakAtNode == 0) return;
2512 if (not_a_node(orig)) orig = nullptr;
2513 int trip = 10;
2514 while (orig != nullptr) {
2515 if (orig->debug_idx() == BreakAtNode || (uintx)orig->_idx == BreakAtNode) {
2516 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=" UINT64_FORMAT " orig._idx=%d orig._debug_idx=" UINT64_FORMAT,
2517 this->_idx, this->debug_idx(), orig->_idx, orig->debug_idx());
2518 BREAKPOINT;
2519 }
2520 orig = orig->debug_orig();
2521 if (not_a_node(orig)) orig = nullptr;
2522 if (trip-- <= 0) break;
2523 }
2524 }
2525 #endif //ASSERT
2526
2527 //------------------------------dump------------------------------------------
2528 // Dump a Node
2529 void Node::dump(const char* suffix, bool mark, outputStream* st, DumpConfig* dc) const {
2530 Compile* C = Compile::current();
2531 bool is_new = C->node_arena()->contains(this);
2532 C->_in_dump_cnt++;
2533
2534 // idx mark name ===
2535 dump_idx(true, st, dc);
2536 st->print(mark ? " >" : " ");
2537 dump_name(st, dc);
2538 st->print(" === ");
2539
2540 // Dump the required and precedence inputs
2541 dump_req(st, dc);
2542 dump_prec(st, dc);
2543 // Dump the outputs
2544 dump_out(st, dc);
2545
2546 if (is_disconnected(this)) {
2547 #ifdef ASSERT
2548 st->print(" [" UINT64_FORMAT "]", debug_idx());
2549 dump_orig(st);
2550 #endif
2551 st->cr();
2552 C->_in_dump_cnt--;
2553 return; // don't process dead nodes
2554 }
2555
2556 if (C->clone_map().value(_idx) != 0) {
2557 C->clone_map().dump(_idx, st);
2558 }
2559 // Dump node-specific info
2560 dump_spec(st);
2561 #ifdef ASSERT
2562 // Dump the non-reset _debug_idx
2563 if (Verbose && WizardMode) {
2564 st->print(" [" UINT64_FORMAT "]", debug_idx());
2565 }
2566 #endif
2567
2568 const Type *t = bottom_type();
2569
2570 if (t != nullptr && (t->isa_instptr() || t->isa_instklassptr())) {
2571 const TypeInstPtr *toop = t->isa_instptr();
2572 const TypeInstKlassPtr *tkls = t->isa_instklassptr();
2573 if (toop) {
2574 st->print(" Oop:");
2575 } else if (tkls) {
2576 st->print(" Klass:");
2577 }
2578 t->dump_on(st);
2579 } else if (t == Type::MEMORY) {
2580 st->print(" Memory:");
2581 MemNode::dump_adr_type(this, adr_type(), st);
2582 } else if (Verbose || WizardMode) {
2583 st->print(" Type:");
2584 if (t) {
2585 t->dump_on(st);
2586 } else {
2587 st->print("no type");
2588 }
2589 } else if (t->isa_vect() && this->is_MachSpillCopy()) {
2590 // Dump MachSpillcopy vector type.
2591 t->dump_on(st);
2592 }
2593 if (is_new) {
2594 DEBUG_ONLY(dump_orig(st));
2595 Node_Notes* nn = C->node_notes_at(_idx);
2596 if (nn != nullptr && !nn->is_clear()) {
2597 if (nn->jvms() != nullptr) {
2598 st->print(" !jvms:");
2599 nn->jvms()->dump_spec(st);
2600 }
2601 }
2602 }
2603 if (suffix) st->print("%s", suffix);
2604 C->_in_dump_cnt--;
2605 }
2606
2607 // call from debugger: dump node to tty with newline
2608 void Node::dump() const {
2609 dump("\n");
2610 }
2611
2612 //------------------------------dump_req--------------------------------------
2613 void Node::dump_req(outputStream* st, DumpConfig* dc) const {
2614 // Dump the required input edges
2615 for (uint i = 0; i < req(); i++) { // For all required inputs
2616 Node* d = in(i);
2617 if (d == nullptr) {
2618 st->print("_ ");
2619 } else if (not_a_node(d)) {
2620 st->print("not_a_node "); // uninitialized, sentinel, garbage, etc.
2621 } else {
2622 d->dump_idx(false, st, dc);
2623 st->print(" ");
2624 }
2625 }
2626 }
2627
2628
2629 //------------------------------dump_prec-------------------------------------
2630 void Node::dump_prec(outputStream* st, DumpConfig* dc) const {
2631 // Dump the precedence edges
2632 int any_prec = 0;
2633 for (uint i = req(); i < len(); i++) { // For all precedence inputs
2634 Node* p = in(i);
2635 if (p != nullptr) {
2636 if (!any_prec++) st->print(" |");
2637 if (not_a_node(p)) { st->print("not_a_node "); continue; }
2638 p->dump_idx(false, st, dc);
2639 st->print(" ");
2640 }
2641 }
2642 }
2643
2644 //------------------------------dump_out--------------------------------------
2645 void Node::dump_out(outputStream* st, DumpConfig* dc) const {
2646 // Delimit the output edges
2647 st->print(" [[ ");
2648 // Dump the output edges
2649 for (uint i = 0; i < _outcnt; i++) { // For all outputs
2650 Node* u = _out[i];
2651 if (u == nullptr) {
2652 st->print("_ ");
2653 } else if (not_a_node(u)) {
2654 st->print("not_a_node ");
2655 } else {
2656 u->dump_idx(false, st, dc);
2657 st->print(" ");
2658 }
2659 }
2660 st->print("]] ");
2661 }
2662
2663 //------------------------------dump-------------------------------------------
2664 // call from debugger: dump Node's inputs (or outputs if d negative)
2665 void Node::dump(int d) const {
2666 dump_bfs(abs(d), nullptr, (d > 0) ? "+$" : "-$");
2667 }
2668
2669 //------------------------------dump_ctrl--------------------------------------
2670 // call from debugger: dump Node's control inputs (or outputs if d negative)
2671 void Node::dump_ctrl(int d) const {
2672 dump_bfs(abs(d), nullptr, (d > 0) ? "+$c" : "-$c");
2673 }
2674
2675 //-----------------------------dump_compact------------------------------------
2676 void Node::dump_comp() const {
2677 this->dump_comp("\n");
2678 }
2679
2680 //-----------------------------dump_compact------------------------------------
2681 // Dump a Node in compact representation, i.e., just print its name and index.
2682 // Nodes can specify additional specifics to print in compact representation by
2683 // implementing dump_compact_spec.
2684 void Node::dump_comp(const char* suffix, outputStream *st) const {
2685 Compile* C = Compile::current();
2686 C->_in_dump_cnt++;
2687 st->print("%s(%d)", Name(), _idx);
2688 this->dump_compact_spec(st);
2689 if (suffix) {
2690 st->print("%s", suffix);
2691 }
2692 C->_in_dump_cnt--;
2693 }
2694
2695 // VERIFICATION CODE
2696 // Verify all nodes if verify_depth is negative
2697 void Node::verify(int verify_depth, VectorSet& visited, Node_List& worklist) {
2698 assert(verify_depth != 0, "depth should not be 0");
2699 Compile* C = Compile::current();
2700 uint last_index_on_current_depth = worklist.size() - 1;
2701 verify_depth--; // Visiting the first node on depth 1
2702 // Only add nodes to worklist if verify_depth is negative (visit all nodes) or greater than 0
2703 bool add_to_worklist = verify_depth != 0;
2704
2705 for (uint list_index = 0; list_index < worklist.size(); list_index++) {
2706 Node* n = worklist[list_index];
2707
2708 if (n->is_Con() && n->bottom_type() == Type::TOP) {
2709 if (C->cached_top_node() == nullptr) {
2710 C->set_cached_top_node((Node*)n);
2711 }
2712 assert(C->cached_top_node() == n, "TOP node must be unique");
2713 }
2714
2715 uint in_len = n->len();
2716 for (uint i = 0; i < in_len; i++) {
2717 Node* x = n->_in[i];
2718 if (!x || x->is_top()) {
2719 continue;
2720 }
2721
2722 // Verify my input has a def-use edge to me
2723 // Count use-def edges from n to x
2724 int cnt = 1;
2725 for (uint j = 0; j < i; j++) {
2726 if (n->_in[j] == x) {
2727 cnt++;
2728 break;
2729 }
2730 }
2731 if (cnt == 2) {
2732 // x is already checked as n's previous input, skip its duplicated def-use count checking
2733 continue;
2734 }
2735 for (uint j = i + 1; j < in_len; j++) {
2736 if (n->_in[j] == x) {
2737 cnt++;
2738 }
2739 }
2740
2741 // Count def-use edges from x to n
2742 uint max = x->_outcnt;
2743 for (uint k = 0; k < max; k++) {
2744 if (x->_out[k] == n) {
2745 cnt--;
2746 }
2747 }
2748 assert(cnt == 0, "mismatched def-use edge counts");
2749
2750 if (add_to_worklist && !visited.test_set(x->_idx)) {
2751 worklist.push(x);
2752 }
2753 }
2754
2755 if (verify_depth > 0 && list_index == last_index_on_current_depth) {
2756 // All nodes on this depth were processed and its inputs are on the worklist. Decrement verify_depth and
2757 // store the current last list index which is the last node in the list with the new depth. All nodes
2758 // added afterwards will have a new depth again. Stop adding new nodes if depth limit is reached (=0).
2759 verify_depth--;
2760 if (verify_depth == 0) {
2761 add_to_worklist = false;
2762 }
2763 last_index_on_current_depth = worklist.size() - 1;
2764 }
2765 }
2766 }
2767 #endif // not PRODUCT
2768
2769 //------------------------------Registers--------------------------------------
2770 // Do we Match on this edge index or not? Generally false for Control
2771 // and true for everything else. Weird for calls & returns.
2772 uint Node::match_edge(uint idx) const {
2773 return idx; // True for other than index 0 (control)
2774 }
2775
2776 // Register classes are defined for specific machines
2777 const RegMask &Node::out_RegMask() const {
2778 ShouldNotCallThis();
2779 return RegMask::Empty;
2780 }
2781
2782 const RegMask &Node::in_RegMask(uint) const {
2783 ShouldNotCallThis();
2784 return RegMask::Empty;
2785 }
2786
2787 void Node_Array::grow(uint i) {
2788 _nesting.check(_a); // Check if a potential reallocation in the arena is safe
2789 assert(i >= _max, "Should have been checked before, use maybe_grow?");
2790 assert(_max > 0, "invariant");
2791 uint old = _max;
2792 _max = next_power_of_2(i);
2793 _nodes = (Node**)_a->Arealloc( _nodes, old*sizeof(Node*),_max*sizeof(Node*));
2794 Copy::zero_to_bytes( &_nodes[old], (_max-old)*sizeof(Node*) );
2795 }
2796
2797 void Node_Array::insert(uint i, Node* n) {
2798 if (_nodes[_max - 1]) {
2799 grow(_max);
2800 }
2801 Copy::conjoint_words_to_higher((HeapWord*)&_nodes[i], (HeapWord*)&_nodes[i + 1], ((_max - i - 1) * sizeof(Node*)));
2802 _nodes[i] = n;
2803 }
2804
2805 void Node_Array::remove(uint i) {
2806 Copy::conjoint_words_to_lower((HeapWord*)&_nodes[i + 1], (HeapWord*)&_nodes[i], ((_max - i - 1) * sizeof(Node*)));
2807 _nodes[_max - 1] = nullptr;
2808 }
2809
2810 void Node_Array::dump() const {
2811 #ifndef PRODUCT
2812 for (uint i = 0; i < _max; i++) {
2813 Node* nn = _nodes[i];
2814 if (nn != nullptr) {
2815 tty->print("%5d--> ",i); nn->dump();
2816 }
2817 }
2818 #endif
2819 }
2820
2821 //--------------------------is_iteratively_computed------------------------------
2822 // Operation appears to be iteratively computed (such as an induction variable)
2823 // It is possible for this operation to return false for a loop-varying
2824 // value, if it appears (by local graph inspection) to be computed by a simple conditional.
2825 bool Node::is_iteratively_computed() {
2826 if (ideal_reg()) { // does operation have a result register?
2827 for (uint i = 1; i < req(); i++) {
2828 Node* n = in(i);
2829 if (n != nullptr && n->is_Phi()) {
2830 for (uint j = 1; j < n->req(); j++) {
2831 if (n->in(j) == this) {
2832 return true;
2833 }
2834 }
2835 }
2836 }
2837 }
2838 return false;
2839 }
2840
2841 //--------------------------find_similar------------------------------
2842 // Return a node with opcode "opc" and same inputs as "this" if one can
2843 // be found; Otherwise return null;
2844 Node* Node::find_similar(int opc) {
2845 if (req() >= 2) {
2846 Node* def = in(1);
2847 if (def && def->outcnt() >= 2) {
2848 for (DUIterator_Fast dmax, i = def->fast_outs(dmax); i < dmax; i++) {
2849 Node* use = def->fast_out(i);
2850 if (use != this &&
2851 use->Opcode() == opc &&
2852 use->req() == req()) {
2853 uint j;
2854 for (j = 0; j < use->req(); j++) {
2855 if (use->in(j) != in(j)) {
2856 break;
2857 }
2858 }
2859 if (j == use->req()) {
2860 return use;
2861 }
2862 }
2863 }
2864 }
2865 }
2866 return nullptr;
2867 }
2868
2869
2870 //--------------------------unique_ctrl_out_or_null-------------------------
2871 // Return the unique control out if only one. Null if none or more than one.
2872 Node* Node::unique_ctrl_out_or_null() const {
2873 Node* found = nullptr;
2874 for (uint i = 0; i < outcnt(); i++) {
2875 Node* use = raw_out(i);
2876 if (use->is_CFG() && use != this) {
2877 if (found != nullptr) {
2878 return nullptr;
2879 }
2880 found = use;
2881 }
2882 }
2883 return found;
2884 }
2885
2886 //--------------------------unique_ctrl_out------------------------------
2887 // Return the unique control out. Asserts if none or more than one control out.
2888 Node* Node::unique_ctrl_out() const {
2889 Node* ctrl = unique_ctrl_out_or_null();
2890 assert(ctrl != nullptr, "control out is assumed to be unique");
2891 return ctrl;
2892 }
2893
2894 void Node::ensure_control_or_add_prec(Node* c) {
2895 if (in(0) == nullptr) {
2896 set_req(0, c);
2897 } else if (in(0) != c) {
2898 add_prec(c);
2899 }
2900 }
2901
2902 void Node::add_prec_from(Node* n) {
2903 for (uint i = n->req(); i < n->len(); i++) {
2904 Node* prec = n->in(i);
2905 if (prec != nullptr) {
2906 add_prec(prec);
2907 }
2908 }
2909 }
2910
2911 bool Node::is_dead_loop_safe() const {
2912 if (is_Phi()) {
2913 return true;
2914 }
2915 if (is_Proj() && in(0) == nullptr) {
2916 return true;
2917 }
2918 if ((_flags & (Flag_is_dead_loop_safe | Flag_is_Con)) != 0) {
2919 if (!is_Proj()) {
2920 return true;
2921 }
2922 if (in(0)->is_Allocate()) {
2923 return false;
2924 }
2925 // MemNode::can_see_stored_value() peeks through the boxing call
2926 if (in(0)->is_CallStaticJava() && in(0)->as_CallStaticJava()->is_boxing_method()) {
2927 return false;
2928 }
2929 return true;
2930 }
2931 return false;
2932 }
2933
2934 bool Node::is_div_or_mod(BasicType bt) const { return Opcode() == Op_Div(bt) || Opcode() == Op_Mod(bt) ||
2935 Opcode() == Op_UDiv(bt) || Opcode() == Op_UMod(bt); }
2936
2937 bool Node::is_pure_function() const {
2938 switch (Opcode()) {
2939 case Op_ModD:
2940 case Op_ModF:
2941 return true;
2942 default:
2943 return false;
2944 }
2945 }
2946
2947 // `maybe_pure_function` is assumed to be the input of `this`. This is a bit redundant,
2948 // but we already have and need maybe_pure_function in all the call sites, so
2949 // it makes it obvious that the `maybe_pure_function` is the same node as in the caller,
2950 // while it takes more thinking to realize that a locally computed in(0) must be equal to
2951 // the local in the caller.
2952 bool Node::is_data_proj_of_pure_function(const Node* maybe_pure_function) const {
2953 return Opcode() == Op_Proj && as_Proj()->_con == TypeFunc::Parms && maybe_pure_function->is_pure_function();
2954 }
2955
2956 //=============================================================================
2957 //------------------------------yank-------------------------------------------
2958 // Find and remove
2959 void Node_List::yank( Node *n ) {
2960 uint i;
2961 for (i = 0; i < _cnt; i++) {
2962 if (_nodes[i] == n) {
2963 break;
2964 }
2965 }
2966
2967 if (i < _cnt) {
2968 _nodes[i] = _nodes[--_cnt];
2969 }
2970 }
2971
2972 //------------------------------dump-------------------------------------------
2973 void Node_List::dump() const {
2974 #ifndef PRODUCT
2975 for (uint i = 0; i < _cnt; i++) {
2976 if (_nodes[i]) {
2977 tty->print("%5d--> ", i);
2978 _nodes[i]->dump();
2979 }
2980 }
2981 #endif
2982 }
2983
2984 void Node_List::dump_simple() const {
2985 #ifndef PRODUCT
2986 for (uint i = 0; i < _cnt; i++) {
2987 if( _nodes[i] ) {
2988 tty->print(" %d", _nodes[i]->_idx);
2989 } else {
2990 tty->print(" null");
2991 }
2992 }
2993 #endif
2994 }
2995
2996 //=============================================================================
2997 //------------------------------remove-----------------------------------------
2998 void Unique_Node_List::remove(Node* n) {
2999 if (_in_worklist.test(n->_idx)) {
3000 for (uint i = 0; i < size(); i++) {
3001 if (_nodes[i] == n) {
3002 map(i, Node_List::pop());
3003 _in_worklist.remove(n->_idx);
3004 return;
3005 }
3006 }
3007 ShouldNotReachHere();
3008 }
3009 }
3010
3011 //-----------------------remove_useless_nodes----------------------------------
3012 // Remove useless nodes from worklist
3013 void Unique_Node_List::remove_useless_nodes(VectorSet &useful) {
3014 for (uint i = 0; i < size(); ++i) {
3015 Node *n = at(i);
3016 assert( n != nullptr, "Did not expect null entries in worklist");
3017 if (!useful.test(n->_idx)) {
3018 _in_worklist.remove(n->_idx);
3019 map(i, Node_List::pop());
3020 --i; // Visit popped node
3021 // If it was last entry, loop terminates since size() was also reduced
3022 }
3023 }
3024 }
3025
3026 //=============================================================================
3027 void Node_Stack::grow() {
3028 _nesting.check(_a); // Check if a potential reallocation in the arena is safe
3029 if (_inode_top < _inode_max) {
3030 return; // No need to grow
3031 }
3032 size_t old_top = pointer_delta(_inode_top,_inodes,sizeof(INode)); // save _top
3033 size_t old_max = pointer_delta(_inode_max,_inodes,sizeof(INode));
3034 size_t max = old_max << 1; // max * 2
3035 _inodes = REALLOC_ARENA_ARRAY(_a, INode, _inodes, old_max, max);
3036 _inode_max = _inodes + max;
3037 _inode_top = _inodes + old_top; // restore _top
3038 }
3039
3040 // Node_Stack is used to map nodes.
3041 Node* Node_Stack::find(uint idx) const {
3042 uint sz = size();
3043 for (uint i = 0; i < sz; i++) {
3044 if (idx == index_at(i)) {
3045 return node_at(i);
3046 }
3047 }
3048 return nullptr;
3049 }
3050
3051 //=============================================================================
3052 uint TypeNode::size_of() const { return sizeof(*this); }
3053 #ifndef PRODUCT
3054 void TypeNode::dump_spec(outputStream *st) const {
3055 if (!Verbose && !WizardMode) {
3056 // standard dump does this in Verbose and WizardMode
3057 st->print(" #"); _type->dump_on(st);
3058 }
3059 }
3060
3061 void TypeNode::dump_compact_spec(outputStream *st) const {
3062 st->print("#");
3063 _type->dump_on(st);
3064 }
3065 #endif
3066 uint TypeNode::hash() const {
3067 return Node::hash() + _type->hash();
3068 }
3069 bool TypeNode::cmp(const Node& n) const {
3070 return Type::equals(_type, n.as_Type()->_type);
3071 }
3072 const Type* TypeNode::bottom_type() const { return _type; }
3073 const Type* TypeNode::Value(PhaseGVN* phase) const { return _type; }
3074
3075 //------------------------------ideal_reg--------------------------------------
3076 uint TypeNode::ideal_reg() const {
3077 return _type->ideal_reg();
3078 }