1 /*
2 * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
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 (n->is_ParsePredicate()) {
512 C->add_parse_predicate(n->as_ParsePredicate());
513 }
514
515 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
516 bs->register_potential_barrier_node(n);
517
518 n->set_idx(C->next_unique()); // Get new unique index as well
519 NOT_PRODUCT(n->_igv_idx = C->next_igv_idx());
520 debug_only( n->verify_construction() );
521 NOT_PRODUCT(nodes_created++);
522 // Do not patch over the debug_idx of a clone, because it makes it
523 // impossible to break on the clone's moment of creation.
524 //debug_only( n->set_debug_idx( debug_idx() ) );
525
526 C->copy_node_notes_to(n, (Node*) this);
527
528 // MachNode clone
529 uint nopnds;
530 if (this->is_Mach() && (nopnds = this->as_Mach()->num_opnds()) > 0) {
531 MachNode *mach = n->as_Mach();
532 MachNode *mthis = this->as_Mach();
533 // Get address of _opnd_array.
534 // It should be the same offset since it is the clone of this node.
535 MachOper **from = mthis->_opnds;
536 MachOper **to = (MachOper **)((size_t)(&mach->_opnds) +
537 pointer_delta((const void*)from,
538 (const void*)(&mthis->_opnds), 1));
539 mach->_opnds = to;
540 for ( uint i = 0; i < nopnds; ++i ) {
541 to[i] = from[i]->clone();
542 }
543 }
544 if (n->is_Call()) {
545 // CallGenerator is linked to the original node.
546 CallGenerator* cg = n->as_Call()->generator();
547 if (cg != nullptr) {
548 CallGenerator* cloned_cg = cg->with_call_node(n->as_Call());
549 n->as_Call()->set_generator(cloned_cg);
550
551 C->print_inlining_assert_ready();
552 C->print_inlining_move_to(cg);
553 C->print_inlining_update(cloned_cg);
554 }
555 }
556 if (n->is_SafePoint()) {
557 // Scalar replacement and macro expansion might modify the JVMState.
558 // Clone it to make sure it's not shared between SafePointNodes.
559 n->as_SafePoint()->clone_jvms(C);
560 n->as_SafePoint()->clone_replaced_nodes();
561 }
562 Compile::current()->record_modified_node(n);
563 return n; // Return the clone
564 }
565
566 //---------------------------setup_is_top--------------------------------------
567 // Call this when changing the top node, to reassert the invariants
568 // required by Node::is_top. See Compile::set_cached_top_node.
569 void Node::setup_is_top() {
570 if (this == (Node*)Compile::current()->top()) {
571 // This node has just become top. Kill its out array.
572 _outcnt = _outmax = 0;
573 _out = nullptr; // marker value for top
574 assert(is_top(), "must be top");
575 } else {
576 if (_out == nullptr) _out = NO_OUT_ARRAY;
577 assert(!is_top(), "must not be top");
578 }
579 }
580
581 //------------------------------~Node------------------------------------------
582 // Fancy destructor; eagerly attempt to reclaim Node numberings and storage
583 void Node::destruct(PhaseValues* phase) {
584 Compile* compile = (phase != nullptr) ? phase->C : Compile::current();
585 if (phase != nullptr && phase->is_IterGVN()) {
586 phase->is_IterGVN()->_worklist.remove(this);
587 }
588 // If this is the most recently created node, reclaim its index. Otherwise,
589 // record the node as dead to keep liveness information accurate.
590 if ((uint)_idx+1 == compile->unique()) {
591 compile->set_unique(compile->unique()-1);
592 } else {
593 compile->record_dead_node(_idx);
594 }
595 // Clear debug info:
596 Node_Notes* nn = compile->node_notes_at(_idx);
597 if (nn != nullptr) nn->clear();
598 // Walk the input array, freeing the corresponding output edges
599 _cnt = _max; // forget req/prec distinction
600 uint i;
601 for( i = 0; i < _max; i++ ) {
602 set_req(i, nullptr);
603 //assert(def->out(def->outcnt()-1) == (Node *)this,"bad def-use hacking in reclaim");
604 }
605 assert(outcnt() == 0, "deleting a node must not leave a dangling use");
606
607 if (is_macro()) {
608 compile->remove_macro_node(this);
609 }
610 if (is_expensive()) {
611 compile->remove_expensive_node(this);
612 }
613 if (Opcode() == Op_Opaque4) {
614 compile->remove_template_assertion_predicate_opaq(this);
615 }
616 if (is_ParsePredicate()) {
617 compile->remove_parse_predicate(as_ParsePredicate());
618 }
619 if (for_post_loop_opts_igvn()) {
620 compile->remove_from_post_loop_opts_igvn(this);
621 }
622
623 if (is_SafePoint()) {
624 as_SafePoint()->delete_replaced_nodes();
625
626 if (is_CallStaticJava()) {
627 compile->remove_unstable_if_trap(as_CallStaticJava(), false);
628 }
629 }
630 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
631 bs->unregister_potential_barrier_node(this);
632
633 // See if the input array was allocated just prior to the object
634 int edge_size = _max*sizeof(void*);
635 int out_edge_size = _outmax*sizeof(void*);
636 char *in_array = ((char*)_in);
637 char *edge_end = in_array + edge_size;
638 char *out_array = (char*)(_out == NO_OUT_ARRAY? nullptr: _out);
639 int node_size = size_of();
640
641 #ifdef ASSERT
642 // We will not actually delete the storage, but we'll make the node unusable.
643 compile->remove_modified_node(this);
644 *(address*)this = badAddress; // smash the C++ vtbl, probably
645 _in = _out = (Node**) badAddress;
646 _max = _cnt = _outmax = _outcnt = 0;
647 #endif
648
649 // Free the output edge array
650 if (out_edge_size > 0) {
651 compile->node_arena()->Afree(out_array, out_edge_size);
652 }
653
654 // Free the input edge array and the node itself
655 if( edge_end == (char*)this ) {
656 // It was; free the input array and object all in one hit
657 #ifndef ASSERT
658 compile->node_arena()->Afree(in_array, edge_size+node_size);
659 #endif
660 } else {
661 // Free just the input array
662 compile->node_arena()->Afree(in_array, edge_size);
663
664 // Free just the object
665 #ifndef ASSERT
666 compile->node_arena()->Afree(this, node_size);
667 #endif
668 }
669 }
670
671 //------------------------------grow-------------------------------------------
672 // Grow the input array, making space for more edges
673 void Node::grow(uint len) {
674 Arena* arena = Compile::current()->node_arena();
675 uint new_max = _max;
676 if( new_max == 0 ) {
677 _max = 4;
678 _in = (Node**)arena->Amalloc(4*sizeof(Node*));
679 Node** to = _in;
680 to[0] = nullptr;
681 to[1] = nullptr;
682 to[2] = nullptr;
683 to[3] = nullptr;
684 return;
685 }
686 new_max = next_power_of_2(len);
687 // Trimming to limit allows a uint8 to handle up to 255 edges.
688 // Previously I was using only powers-of-2 which peaked at 128 edges.
689 //if( new_max >= limit ) new_max = limit-1;
690 _in = (Node**)arena->Arealloc(_in, _max*sizeof(Node*), new_max*sizeof(Node*));
691 Copy::zero_to_bytes(&_in[_max], (new_max-_max)*sizeof(Node*)); // null all new space
692 _max = new_max; // Record new max length
693 // This assertion makes sure that Node::_max is wide enough to
694 // represent the numerical value of new_max.
695 assert(_max == new_max && _max > len, "int width of _max is too small");
696 }
697
698 //-----------------------------out_grow----------------------------------------
699 // Grow the input array, making space for more edges
700 void Node::out_grow( uint len ) {
701 assert(!is_top(), "cannot grow a top node's out array");
702 Arena* arena = Compile::current()->node_arena();
703 uint new_max = _outmax;
704 if( new_max == 0 ) {
705 _outmax = 4;
706 _out = (Node **)arena->Amalloc(4*sizeof(Node*));
707 return;
708 }
709 new_max = next_power_of_2(len);
710 // Trimming to limit allows a uint8 to handle up to 255 edges.
711 // Previously I was using only powers-of-2 which peaked at 128 edges.
712 //if( new_max >= limit ) new_max = limit-1;
713 assert(_out != nullptr && _out != NO_OUT_ARRAY, "out must have sensible value");
714 _out = (Node**)arena->Arealloc(_out,_outmax*sizeof(Node*),new_max*sizeof(Node*));
715 //Copy::zero_to_bytes(&_out[_outmax], (new_max-_outmax)*sizeof(Node*)); // null all new space
716 _outmax = new_max; // Record new max length
717 // This assertion makes sure that Node::_max is wide enough to
718 // represent the numerical value of new_max.
719 assert(_outmax == new_max && _outmax > len, "int width of _outmax is too small");
720 }
721
722 #ifdef ASSERT
723 //------------------------------is_dead----------------------------------------
724 bool Node::is_dead() const {
725 // Mach and pinch point nodes may look like dead.
726 if( is_top() || is_Mach() || (Opcode() == Op_Node && _outcnt > 0) )
727 return false;
728 for( uint i = 0; i < _max; i++ )
729 if( _in[i] != nullptr )
730 return false;
731 return true;
732 }
733
734 bool Node::is_not_dead(const Node* n) {
735 return n == nullptr || !PhaseIterGVN::is_verify_def_use() || !(n->is_dead());
736 }
737
738 bool Node::is_reachable_from_root() const {
739 ResourceMark rm;
740 Unique_Node_List wq;
741 wq.push((Node*)this);
742 RootNode* root = Compile::current()->root();
743 for (uint i = 0; i < wq.size(); i++) {
744 Node* m = wq.at(i);
745 if (m == root) {
746 return true;
747 }
748 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
749 Node* u = m->fast_out(j);
750 wq.push(u);
751 }
752 }
753 return false;
754 }
755 #endif
756
757 //------------------------------is_unreachable---------------------------------
758 bool Node::is_unreachable(PhaseIterGVN &igvn) const {
759 assert(!is_Mach(), "doesn't work with MachNodes");
760 return outcnt() == 0 || igvn.type(this) == Type::TOP || (in(0) != nullptr && in(0)->is_top());
761 }
762
763 //------------------------------add_req----------------------------------------
764 // Add a new required input at the end
765 void Node::add_req( Node *n ) {
766 assert( is_not_dead(n), "can not use dead node");
767
768 // Look to see if I can move precedence down one without reallocating
769 if( (_cnt >= _max) || (in(_max-1) != nullptr) )
770 grow( _max+1 );
771
772 // Find a precedence edge to move
773 if( in(_cnt) != nullptr ) { // Next precedence edge is busy?
774 uint i;
775 for( i=_cnt; i<_max; i++ )
776 if( in(i) == nullptr ) // Find the null at end of prec edge list
777 break; // There must be one, since we grew the array
778 _in[i] = in(_cnt); // Move prec over, making space for req edge
779 }
780 _in[_cnt++] = n; // Stuff over old prec edge
781 if (n != nullptr) n->add_out((Node *)this);
782 Compile::current()->record_modified_node(this);
783 }
784
785 //---------------------------add_req_batch-------------------------------------
786 // Add a new required input at the end
787 void Node::add_req_batch( Node *n, uint m ) {
788 assert( is_not_dead(n), "can not use dead node");
789 // check various edge cases
790 if ((int)m <= 1) {
791 assert((int)m >= 0, "oob");
792 if (m != 0) add_req(n);
793 return;
794 }
795
796 // Look to see if I can move precedence down one without reallocating
797 if( (_cnt+m) > _max || _in[_max-m] )
798 grow( _max+m );
799
800 // Find a precedence edge to move
801 if( _in[_cnt] != nullptr ) { // Next precedence edge is busy?
802 uint i;
803 for( i=_cnt; i<_max; i++ )
804 if( _in[i] == nullptr ) // Find the null at end of prec edge list
805 break; // There must be one, since we grew the array
806 // Slide all the precs over by m positions (assume #prec << m).
807 Copy::conjoint_words_to_higher((HeapWord*)&_in[_cnt], (HeapWord*)&_in[_cnt+m], ((i-_cnt)*sizeof(Node*)));
808 }
809
810 // Stuff over the old prec edges
811 for(uint i=0; i<m; i++ ) {
812 _in[_cnt++] = n;
813 }
814
815 // Insert multiple out edges on the node.
816 if (n != nullptr && !n->is_top()) {
817 for(uint i=0; i<m; i++ ) {
818 n->add_out((Node *)this);
819 }
820 }
821 Compile::current()->record_modified_node(this);
822 }
823
824 //------------------------------del_req----------------------------------------
825 // Delete the required edge and compact the edge array
826 void Node::del_req( uint idx ) {
827 assert( idx < _cnt, "oob");
828 assert( !VerifyHashTableKeys || _hash_lock == 0,
829 "remove node from hash table before modifying it");
830 // First remove corresponding def-use edge
831 Node *n = in(idx);
832 if (n != nullptr) n->del_out((Node *)this);
833 _in[idx] = in(--_cnt); // Compact the array
834 // Avoid spec violation: Gap in prec edges.
835 close_prec_gap_at(_cnt);
836 Compile::current()->record_modified_node(this);
837 }
838
839 //------------------------------del_req_ordered--------------------------------
840 // Delete the required edge and compact the edge array with preserved order
841 void Node::del_req_ordered( uint idx ) {
842 assert( idx < _cnt, "oob");
843 assert( !VerifyHashTableKeys || _hash_lock == 0,
844 "remove node from hash table before modifying it");
845 // First remove corresponding def-use edge
846 Node *n = in(idx);
847 if (n != nullptr) n->del_out((Node *)this);
848 if (idx < --_cnt) { // Not last edge ?
849 Copy::conjoint_words_to_lower((HeapWord*)&_in[idx+1], (HeapWord*)&_in[idx], ((_cnt-idx)*sizeof(Node*)));
850 }
851 // Avoid spec violation: Gap in prec edges.
852 close_prec_gap_at(_cnt);
853 Compile::current()->record_modified_node(this);
854 }
855
856 //------------------------------ins_req----------------------------------------
857 // Insert a new required input at the end
858 void Node::ins_req( uint idx, Node *n ) {
859 assert( is_not_dead(n), "can not use dead node");
860 add_req(nullptr); // Make space
861 assert( idx < _max, "Must have allocated enough space");
862 // Slide over
863 if(_cnt-idx-1 > 0) {
864 Copy::conjoint_words_to_higher((HeapWord*)&_in[idx], (HeapWord*)&_in[idx+1], ((_cnt-idx-1)*sizeof(Node*)));
865 }
866 _in[idx] = n; // Stuff over old required edge
867 if (n != nullptr) n->add_out((Node *)this); // Add reciprocal def-use edge
868 Compile::current()->record_modified_node(this);
869 }
870
871 //-----------------------------find_edge---------------------------------------
872 int Node::find_edge(Node* n) {
873 for (uint i = 0; i < len(); i++) {
874 if (_in[i] == n) return i;
875 }
876 return -1;
877 }
878
879 //----------------------------replace_edge-------------------------------------
880 int Node::replace_edge(Node* old, Node* neww, PhaseGVN* gvn) {
881 if (old == neww) return 0; // nothing to do
882 uint nrep = 0;
883 for (uint i = 0; i < len(); i++) {
884 if (in(i) == old) {
885 if (i < req()) {
886 if (gvn != nullptr) {
887 set_req_X(i, neww, gvn);
888 } else {
889 set_req(i, neww);
890 }
891 } else {
892 assert(gvn == nullptr || gvn->is_IterGVN() == nullptr, "no support for igvn here");
893 assert(find_prec_edge(neww) == -1, "spec violation: duplicated prec edge (node %d -> %d)", _idx, neww->_idx);
894 set_prec(i, neww);
895 }
896 nrep++;
897 }
898 }
899 return nrep;
900 }
901
902 /**
903 * Replace input edges in the range pointing to 'old' node.
904 */
905 int Node::replace_edges_in_range(Node* old, Node* neww, int start, int end, PhaseGVN* gvn) {
906 if (old == neww) return 0; // nothing to do
907 uint nrep = 0;
908 for (int i = start; i < end; i++) {
909 if (in(i) == old) {
910 set_req_X(i, neww, gvn);
911 nrep++;
912 }
913 }
914 return nrep;
915 }
916
917 //-------------------------disconnect_inputs-----------------------------------
918 // null out all inputs to eliminate incoming Def-Use edges.
919 void Node::disconnect_inputs(Compile* C) {
920 // the layout of Node::_in
921 // r: a required input, null is allowed
922 // p: a precedence, null values are all at the end
923 // -----------------------------------
924 // |r|...|r|p|...|p|null|...|null|
925 // | |
926 // req() len()
927 // -----------------------------------
928 for (uint i = 0; i < req(); ++i) {
929 if (in(i) != nullptr) {
930 set_req(i, nullptr);
931 }
932 }
933
934 // Remove precedence edges if any exist
935 // Note: Safepoints may have precedence edges, even during parsing
936 for (uint i = len(); i > req(); ) {
937 rm_prec(--i); // no-op if _in[i] is null
938 }
939
940 #ifdef ASSERT
941 // sanity check
942 for (uint i = 0; i < len(); ++i) {
943 assert(_in[i] == nullptr, "disconnect_inputs() failed!");
944 }
945 #endif
946
947 // Node::destruct requires all out edges be deleted first
948 // debug_only(destruct();) // no reuse benefit expected
949 C->record_dead_node(_idx);
950 }
951
952 //-----------------------------uncast---------------------------------------
953 // %%% Temporary, until we sort out CheckCastPP vs. CastPP.
954 // Strip away casting. (It is depth-limited.)
955 // Optionally, keep casts with dependencies.
956 Node* Node::uncast(bool keep_deps) const {
957 // Should be inline:
958 //return is_ConstraintCast() ? uncast_helper(this) : (Node*) this;
959 if (is_ConstraintCast()) {
960 return uncast_helper(this, keep_deps);
961 } else {
962 return (Node*) this;
963 }
964 }
965
966 // Find out of current node that matches opcode.
967 Node* Node::find_out_with(int opcode) {
968 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
969 Node* use = fast_out(i);
970 if (use->Opcode() == opcode) {
971 return use;
972 }
973 }
974 return nullptr;
975 }
976
977 // Return true if the current node has an out that matches opcode.
978 bool Node::has_out_with(int opcode) {
979 return (find_out_with(opcode) != nullptr);
980 }
981
982 // Return true if the current node has an out that matches any of the opcodes.
983 bool Node::has_out_with(int opcode1, int opcode2, int opcode3, int opcode4) {
984 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
985 int opcode = fast_out(i)->Opcode();
986 if (opcode == opcode1 || opcode == opcode2 || opcode == opcode3 || opcode == opcode4) {
987 return true;
988 }
989 }
990 return false;
991 }
992
993
994 //---------------------------uncast_helper-------------------------------------
995 Node* Node::uncast_helper(const Node* p, bool keep_deps) {
996 #ifdef ASSERT
997 uint depth_count = 0;
998 const Node* orig_p = p;
999 #endif
1000
1001 while (true) {
1002 #ifdef ASSERT
1003 if (depth_count >= K) {
1004 orig_p->dump(4);
1005 if (p != orig_p)
1006 p->dump(1);
1007 }
1008 assert(depth_count++ < K, "infinite loop in Node::uncast_helper");
1009 #endif
1010 if (p == nullptr || p->req() != 2) {
1011 break;
1012 } else if (p->is_ConstraintCast()) {
1013 if (keep_deps && p->as_ConstraintCast()->carry_dependency()) {
1014 break; // stop at casts with dependencies
1015 }
1016 p = p->in(1);
1017 } else {
1018 break;
1019 }
1020 }
1021 return (Node*) p;
1022 }
1023
1024 //------------------------------add_prec---------------------------------------
1025 // Add a new precedence input. Precedence inputs are unordered, with
1026 // duplicates removed and nulls packed down at the end.
1027 void Node::add_prec( Node *n ) {
1028 assert( is_not_dead(n), "can not use dead node");
1029
1030 // Check for null at end
1031 if( _cnt >= _max || in(_max-1) )
1032 grow( _max+1 );
1033
1034 // Find a precedence edge to move
1035 uint i = _cnt;
1036 while( in(i) != nullptr ) {
1037 if (in(i) == n) return; // Avoid spec violation: duplicated prec edge.
1038 i++;
1039 }
1040 _in[i] = n; // Stuff prec edge over null
1041 if ( n != nullptr) n->add_out((Node *)this); // Add mirror edge
1042
1043 #ifdef ASSERT
1044 while ((++i)<_max) { assert(_in[i] == nullptr, "spec violation: Gap in prec edges (node %d)", _idx); }
1045 #endif
1046 Compile::current()->record_modified_node(this);
1047 }
1048
1049 //------------------------------rm_prec----------------------------------------
1050 // Remove a precedence input. Precedence inputs are unordered, with
1051 // duplicates removed and nulls packed down at the end.
1052 void Node::rm_prec( uint j ) {
1053 assert(j < _max, "oob: i=%d, _max=%d", j, _max);
1054 assert(j >= _cnt, "not a precedence edge");
1055 if (_in[j] == nullptr) return; // Avoid spec violation: Gap in prec edges.
1056 _in[j]->del_out((Node *)this);
1057 close_prec_gap_at(j);
1058 Compile::current()->record_modified_node(this);
1059 }
1060
1061 //------------------------------size_of----------------------------------------
1062 uint Node::size_of() const { return sizeof(*this); }
1063
1064 //------------------------------ideal_reg--------------------------------------
1065 uint Node::ideal_reg() const { return 0; }
1066
1067 //------------------------------jvms-------------------------------------------
1068 JVMState* Node::jvms() const { return nullptr; }
1069
1070 #ifdef ASSERT
1071 //------------------------------jvms-------------------------------------------
1072 bool Node::verify_jvms(const JVMState* using_jvms) const {
1073 for (JVMState* jvms = this->jvms(); jvms != nullptr; jvms = jvms->caller()) {
1074 if (jvms == using_jvms) return true;
1075 }
1076 return false;
1077 }
1078
1079 //------------------------------init_NodeProperty------------------------------
1080 void Node::init_NodeProperty() {
1081 assert(_max_classes <= max_juint, "too many NodeProperty classes");
1082 assert(max_flags() <= max_juint, "too many NodeProperty flags");
1083 }
1084
1085 //-----------------------------max_flags---------------------------------------
1086 juint Node::max_flags() {
1087 return (PD::_last_flag << 1) - 1; // allow flags combination
1088 }
1089 #endif
1090
1091 //------------------------------format-----------------------------------------
1092 // Print as assembly
1093 void Node::format( PhaseRegAlloc *, outputStream *st ) const {}
1094 //------------------------------emit-------------------------------------------
1095 // Emit bytes starting at parameter 'ptr'.
1096 void Node::emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const {}
1097 //------------------------------size-------------------------------------------
1098 // Size of instruction in bytes
1099 uint Node::size(PhaseRegAlloc *ra_) const { return 0; }
1100
1101 //------------------------------CFG Construction-------------------------------
1102 // Nodes that end basic blocks, e.g. IfTrue/IfFalse, JumpProjNode, Root,
1103 // Goto and Return.
1104 const Node *Node::is_block_proj() const { return 0; }
1105
1106 // Minimum guaranteed type
1107 const Type *Node::bottom_type() const { return Type::BOTTOM; }
1108
1109
1110 //------------------------------raise_bottom_type------------------------------
1111 // Get the worst-case Type output for this Node.
1112 void Node::raise_bottom_type(const Type* new_type) {
1113 if (is_Type()) {
1114 TypeNode *n = this->as_Type();
1115 if (VerifyAliases) {
1116 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1117 }
1118 n->set_type(new_type);
1119 } else if (is_Load()) {
1120 LoadNode *n = this->as_Load();
1121 if (VerifyAliases) {
1122 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1123 }
1124 n->set_type(new_type);
1125 }
1126 }
1127
1128 //------------------------------Identity---------------------------------------
1129 // Return a node that the given node is equivalent to.
1130 Node* Node::Identity(PhaseGVN* phase) {
1131 return this; // Default to no identities
1132 }
1133
1134 //------------------------------Value------------------------------------------
1135 // Compute a new Type for a node using the Type of the inputs.
1136 const Type* Node::Value(PhaseGVN* phase) const {
1137 return bottom_type(); // Default to worst-case Type
1138 }
1139
1140 //------------------------------Ideal------------------------------------------
1141 //
1142 // 'Idealize' the graph rooted at this Node.
1143 //
1144 // In order to be efficient and flexible there are some subtle invariants
1145 // these Ideal calls need to hold. Running with '-XX:VerifyIterativeGVN=1' checks
1146 // these invariants, although its too slow to have on by default. If you are
1147 // hacking an Ideal call, be sure to test with '-XX:VerifyIterativeGVN=1'
1148 //
1149 // The Ideal call almost arbitrarily reshape the graph rooted at the 'this'
1150 // pointer. If ANY change is made, it must return the root of the reshaped
1151 // graph - even if the root is the same Node. Example: swapping the inputs
1152 // to an AddINode gives the same answer and same root, but you still have to
1153 // return the 'this' pointer instead of null.
1154 //
1155 // You cannot return an OLD Node, except for the 'this' pointer. Use the
1156 // Identity call to return an old Node; basically if Identity can find
1157 // another Node have the Ideal call make no change and return null.
1158 // Example: AddINode::Ideal must check for add of zero; in this case it
1159 // returns null instead of doing any graph reshaping.
1160 //
1161 // You cannot modify any old Nodes except for the 'this' pointer. Due to
1162 // sharing there may be other users of the old Nodes relying on their current
1163 // semantics. Modifying them will break the other users.
1164 // Example: when reshape "(X+3)+4" into "X+7" you must leave the Node for
1165 // "X+3" unchanged in case it is shared.
1166 //
1167 // If you modify the 'this' pointer's inputs, you should use
1168 // 'set_req'. If you are making a new Node (either as the new root or
1169 // some new internal piece) you may use 'init_req' to set the initial
1170 // value. You can make a new Node with either 'new' or 'clone'. In
1171 // either case, def-use info is correctly maintained.
1172 //
1173 // Example: reshape "(X+3)+4" into "X+7":
1174 // set_req(1, in(1)->in(1));
1175 // set_req(2, phase->intcon(7));
1176 // return this;
1177 // Example: reshape "X*4" into "X<<2"
1178 // return new LShiftINode(in(1), phase->intcon(2));
1179 //
1180 // You must call 'phase->transform(X)' on any new Nodes X you make, except
1181 // for the returned root node. Example: reshape "X*31" with "(X<<5)-X".
1182 // Node *shift=phase->transform(new LShiftINode(in(1),phase->intcon(5)));
1183 // return new AddINode(shift, in(1));
1184 //
1185 // When making a Node for a constant use 'phase->makecon' or 'phase->intcon'.
1186 // These forms are faster than 'phase->transform(new ConNode())' and Do
1187 // The Right Thing with def-use info.
1188 //
1189 // You cannot bury the 'this' Node inside of a graph reshape. If the reshaped
1190 // graph uses the 'this' Node it must be the root. If you want a Node with
1191 // the same Opcode as the 'this' pointer use 'clone'.
1192 //
1193 Node *Node::Ideal(PhaseGVN *phase, bool can_reshape) {
1194 return nullptr; // Default to being Ideal already
1195 }
1196
1197 // Some nodes have specific Ideal subgraph transformations only if they are
1198 // unique users of specific nodes. Such nodes should be put on IGVN worklist
1199 // for the transformations to happen.
1200 bool Node::has_special_unique_user() const {
1201 assert(outcnt() == 1, "match only for unique out");
1202 Node* n = unique_out();
1203 int op = Opcode();
1204 if (this->is_Store()) {
1205 // Condition for back-to-back stores folding.
1206 return n->Opcode() == op && n->in(MemNode::Memory) == this;
1207 } else if (this->is_Load() || this->is_DecodeN() || this->is_Phi()) {
1208 // Condition for removing an unused LoadNode or DecodeNNode from the MemBarAcquire precedence input
1209 return n->Opcode() == Op_MemBarAcquire;
1210 } else if (op == Op_AddL) {
1211 // Condition for convL2I(addL(x,y)) ==> addI(convL2I(x),convL2I(y))
1212 return n->Opcode() == Op_ConvL2I && n->in(1) == this;
1213 } else if (op == Op_SubI || op == Op_SubL) {
1214 // Condition for subI(x,subI(y,z)) ==> subI(addI(x,z),y)
1215 return n->Opcode() == op && n->in(2) == this;
1216 } else if (is_If() && (n->is_IfFalse() || n->is_IfTrue())) {
1217 // See IfProjNode::Identity()
1218 return true;
1219 } else if ((is_IfFalse() || is_IfTrue()) && n->is_If()) {
1220 // See IfNode::fold_compares
1221 return true;
1222 } else {
1223 return false;
1224 }
1225 };
1226
1227 //--------------------------find_exact_control---------------------------------
1228 // Skip Proj and CatchProj nodes chains. Check for Null and Top.
1229 Node* Node::find_exact_control(Node* ctrl) {
1230 if (ctrl == nullptr && this->is_Region())
1231 ctrl = this->as_Region()->is_copy();
1232
1233 if (ctrl != nullptr && ctrl->is_CatchProj()) {
1234 if (ctrl->as_CatchProj()->_con == CatchProjNode::fall_through_index)
1235 ctrl = ctrl->in(0);
1236 if (ctrl != nullptr && !ctrl->is_top())
1237 ctrl = ctrl->in(0);
1238 }
1239
1240 if (ctrl != nullptr && ctrl->is_Proj())
1241 ctrl = ctrl->in(0);
1242
1243 return ctrl;
1244 }
1245
1246 //--------------------------dominates------------------------------------------
1247 // Helper function for MemNode::all_controls_dominate().
1248 // Check if 'this' control node dominates or equal to 'sub' control node.
1249 // We already know that if any path back to Root or Start reaches 'this',
1250 // then all paths so, so this is a simple search for one example,
1251 // not an exhaustive search for a counterexample.
1252 bool Node::dominates(Node* sub, Node_List &nlist) {
1253 assert(this->is_CFG(), "expecting control");
1254 assert(sub != nullptr && sub->is_CFG(), "expecting control");
1255
1256 // detect dead cycle without regions
1257 int iterations_without_region_limit = DominatorSearchLimit;
1258
1259 Node* orig_sub = sub;
1260 Node* dom = this;
1261 bool met_dom = false;
1262 nlist.clear();
1263
1264 // Walk 'sub' backward up the chain to 'dom', watching for regions.
1265 // After seeing 'dom', continue up to Root or Start.
1266 // If we hit a region (backward split point), it may be a loop head.
1267 // Keep going through one of the region's inputs. If we reach the
1268 // same region again, go through a different input. Eventually we
1269 // will either exit through the loop head, or give up.
1270 // (If we get confused, break out and return a conservative 'false'.)
1271 while (sub != nullptr) {
1272 if (sub->is_top()) break; // Conservative answer for dead code.
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 true;
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;
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 false;
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 // Conservative answer for dead code.
1366 return false;
1367 }
1368
1369 //------------------------------remove_dead_region-----------------------------
1370 // This control node is dead. Follow the subgraph below it making everything
1371 // using it dead as well. This will happen normally via the usual IterGVN
1372 // worklist but this call is more efficient. Do not update use-def info
1373 // inside the dead region, just at the borders.
1374 static void kill_dead_code( Node *dead, PhaseIterGVN *igvn ) {
1375 // Con's are a popular node to re-hit in the hash table again.
1376 if( dead->is_Con() ) return;
1377
1378 ResourceMark rm;
1379 Node_List nstack;
1380 VectorSet dead_set; // notify uses only once
1381
1382 Node *top = igvn->C->top();
1383 nstack.push(dead);
1384 bool has_irreducible_loop = igvn->C->has_irreducible_loop();
1385
1386 while (nstack.size() > 0) {
1387 dead = nstack.pop();
1388 if (!dead_set.test_set(dead->_idx)) {
1389 // If dead has any live uses, those are now still attached. Notify them before we lose them.
1390 igvn->add_users_to_worklist(dead);
1391 }
1392 if (dead->Opcode() == Op_SafePoint) {
1393 dead->as_SafePoint()->disconnect_from_root(igvn);
1394 }
1395 if (dead->outcnt() > 0) {
1396 // Keep dead node on stack until all uses are processed.
1397 nstack.push(dead);
1398 // For all Users of the Dead... ;-)
1399 for (DUIterator_Last kmin, k = dead->last_outs(kmin); k >= kmin; ) {
1400 Node* use = dead->last_out(k);
1401 igvn->hash_delete(use); // Yank from hash table prior to mod
1402 if (use->in(0) == dead) { // Found another dead node
1403 assert (!use->is_Con(), "Control for Con node should be Root node.");
1404 use->set_req(0, top); // Cut dead edge to prevent processing
1405 nstack.push(use); // the dead node again.
1406 } else if (!has_irreducible_loop && // Backedge could be alive in irreducible loop
1407 use->is_Loop() && !use->is_Root() && // Don't kill Root (RootNode extends LoopNode)
1408 use->in(LoopNode::EntryControl) == dead) { // Dead loop if its entry is dead
1409 use->set_req(LoopNode::EntryControl, top); // Cut dead edge to prevent processing
1410 use->set_req(0, top); // Cut self edge
1411 nstack.push(use);
1412 } else { // Else found a not-dead user
1413 // Dead if all inputs are top or null
1414 bool dead_use = !use->is_Root(); // Keep empty graph alive
1415 for (uint j = 1; j < use->req(); j++) {
1416 Node* in = use->in(j);
1417 if (in == dead) { // Turn all dead inputs into TOP
1418 use->set_req(j, top);
1419 } else if (in != nullptr && !in->is_top()) {
1420 dead_use = false;
1421 }
1422 }
1423 if (dead_use) {
1424 if (use->is_Region()) {
1425 use->set_req(0, top); // Cut self edge
1426 }
1427 nstack.push(use);
1428 } else {
1429 igvn->_worklist.push(use);
1430 }
1431 }
1432 // Refresh the iterator, since any number of kills might have happened.
1433 k = dead->last_outs(kmin);
1434 }
1435 } else { // (dead->outcnt() == 0)
1436 // Done with outputs.
1437 igvn->hash_delete(dead);
1438 igvn->_worklist.remove(dead);
1439 igvn->set_type(dead, Type::TOP);
1440 // Kill all inputs to the dead guy
1441 for (uint i=0; i < dead->req(); i++) {
1442 Node *n = dead->in(i); // Get input to dead guy
1443 if (n != nullptr && !n->is_top()) { // Input is valid?
1444 dead->set_req(i, top); // Smash input away
1445 if (n->outcnt() == 0) { // Input also goes dead?
1446 if (!n->is_Con())
1447 nstack.push(n); // Clear it out as well
1448 } else if (n->outcnt() == 1 &&
1449 n->has_special_unique_user()) {
1450 igvn->add_users_to_worklist( n );
1451 } else if (n->outcnt() <= 2 && n->is_Store()) {
1452 // Push store's uses on worklist to enable folding optimization for
1453 // store/store and store/load to the same address.
1454 // The restriction (outcnt() <= 2) is the same as in set_req_X()
1455 // and remove_globally_dead_node().
1456 igvn->add_users_to_worklist( n );
1457 } else {
1458 BarrierSet::barrier_set()->barrier_set_c2()->enqueue_useful_gc_barrier(igvn, n);
1459 }
1460 }
1461 }
1462 igvn->C->remove_useless_node(dead);
1463 } // (dead->outcnt() == 0)
1464 } // while (nstack.size() > 0) for outputs
1465 return;
1466 }
1467
1468 //------------------------------remove_dead_region-----------------------------
1469 bool Node::remove_dead_region(PhaseGVN *phase, bool can_reshape) {
1470 Node *n = in(0);
1471 if( !n ) return false;
1472 // Lost control into this guy? I.e., it became unreachable?
1473 // Aggressively kill all unreachable code.
1474 if (can_reshape && n->is_top()) {
1475 kill_dead_code(this, phase->is_IterGVN());
1476 return false; // Node is dead.
1477 }
1478
1479 if( n->is_Region() && n->as_Region()->is_copy() ) {
1480 Node *m = n->nonnull_req();
1481 set_req(0, m);
1482 return true;
1483 }
1484 return false;
1485 }
1486
1487 //------------------------------hash-------------------------------------------
1488 // Hash function over Nodes.
1489 uint Node::hash() const {
1490 uint sum = 0;
1491 for( uint i=0; i<_cnt; i++ ) // Add in all inputs
1492 sum = (sum<<1)-(uintptr_t)in(i); // Ignore embedded nulls
1493 return (sum>>2) + _cnt + Opcode();
1494 }
1495
1496 //------------------------------cmp--------------------------------------------
1497 // Compare special parts of simple Nodes
1498 bool Node::cmp( const Node &n ) const {
1499 return true; // Must be same
1500 }
1501
1502 //------------------------------rematerialize-----------------------------------
1503 // Should we clone rather than spill this instruction?
1504 bool Node::rematerialize() const {
1505 if ( is_Mach() )
1506 return this->as_Mach()->rematerialize();
1507 else
1508 return (_flags & Flag_rematerialize) != 0;
1509 }
1510
1511 //------------------------------needs_anti_dependence_check---------------------
1512 // Nodes which use memory without consuming it, hence need antidependences.
1513 bool Node::needs_anti_dependence_check() const {
1514 if (req() < 2 || (_flags & Flag_needs_anti_dependence_check) == 0) {
1515 return false;
1516 }
1517 return in(1)->bottom_type()->has_memory();
1518 }
1519
1520 // Get an integer constant from a ConNode (or CastIINode).
1521 // Return a default value if there is no apparent constant here.
1522 const TypeInt* Node::find_int_type() const {
1523 if (this->is_Type()) {
1524 return this->as_Type()->type()->isa_int();
1525 } else if (this->is_Con()) {
1526 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1527 return this->bottom_type()->isa_int();
1528 }
1529 return nullptr;
1530 }
1531
1532 const TypeInteger* Node::find_integer_type(BasicType bt) const {
1533 if (this->is_Type()) {
1534 return this->as_Type()->type()->isa_integer(bt);
1535 } else if (this->is_Con()) {
1536 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1537 return this->bottom_type()->isa_integer(bt);
1538 }
1539 return nullptr;
1540 }
1541
1542 // Get a pointer constant from a ConstNode.
1543 // Returns the constant if it is a pointer ConstNode
1544 intptr_t Node::get_ptr() const {
1545 assert( Opcode() == Op_ConP, "" );
1546 return ((ConPNode*)this)->type()->is_ptr()->get_con();
1547 }
1548
1549 // Get a narrow oop constant from a ConNNode.
1550 intptr_t Node::get_narrowcon() const {
1551 assert( Opcode() == Op_ConN, "" );
1552 return ((ConNNode*)this)->type()->is_narrowoop()->get_con();
1553 }
1554
1555 // Get a long constant from a ConNode.
1556 // Return a default value if there is no apparent constant here.
1557 const TypeLong* Node::find_long_type() const {
1558 if (this->is_Type()) {
1559 return this->as_Type()->type()->isa_long();
1560 } else if (this->is_Con()) {
1561 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1562 return this->bottom_type()->isa_long();
1563 }
1564 return nullptr;
1565 }
1566
1567
1568 /**
1569 * Return a ptr type for nodes which should have it.
1570 */
1571 const TypePtr* Node::get_ptr_type() const {
1572 const TypePtr* tp = this->bottom_type()->make_ptr();
1573 #ifdef ASSERT
1574 if (tp == nullptr) {
1575 this->dump(1);
1576 assert((tp != nullptr), "unexpected node type");
1577 }
1578 #endif
1579 return tp;
1580 }
1581
1582 // Get a double constant from a ConstNode.
1583 // Returns the constant if it is a double ConstNode
1584 jdouble Node::getd() const {
1585 assert( Opcode() == Op_ConD, "" );
1586 return ((ConDNode*)this)->type()->is_double_constant()->getd();
1587 }
1588
1589 // Get a float constant from a ConstNode.
1590 // Returns the constant if it is a float ConstNode
1591 jfloat Node::getf() const {
1592 assert( Opcode() == Op_ConF, "" );
1593 return ((ConFNode*)this)->type()->is_float_constant()->getf();
1594 }
1595
1596 #ifndef PRODUCT
1597
1598 // Call this from debugger:
1599 Node* old_root() {
1600 Matcher* matcher = Compile::current()->matcher();
1601 if (matcher != nullptr) {
1602 Node* new_root = Compile::current()->root();
1603 Node* old_root = matcher->find_old_node(new_root);
1604 if (old_root != nullptr) {
1605 return old_root;
1606 }
1607 }
1608 tty->print("old_root: not found.\n");
1609 return nullptr;
1610 }
1611
1612 // BFS traverse all reachable nodes from start, call callback on them
1613 template <typename Callback>
1614 void visit_nodes(Node* start, Callback callback, bool traverse_output, bool only_ctrl) {
1615 Unique_Mixed_Node_List worklist;
1616 worklist.add(start);
1617 for (uint i = 0; i < worklist.size(); i++) {
1618 Node* n = worklist[i];
1619 callback(n);
1620 for (uint i = 0; i < n->len(); i++) {
1621 if (!only_ctrl || n->is_Region() || (n->Opcode() == Op_Root) || (i == TypeFunc::Control)) {
1622 // If only_ctrl is set: Add regions, the root node, or control inputs only
1623 worklist.add(n->in(i));
1624 }
1625 }
1626 if (traverse_output && !only_ctrl) {
1627 for (uint i = 0; i < n->outcnt(); i++) {
1628 worklist.add(n->raw_out(i));
1629 }
1630 }
1631 }
1632 }
1633
1634 // BFS traverse from start, return node with idx
1635 Node* find_node_by_idx(Node* start, uint idx, bool traverse_output, bool only_ctrl) {
1636 ResourceMark rm;
1637 Node* result = nullptr;
1638 auto callback = [&] (Node* n) {
1639 if (n->_idx == idx) {
1640 if (result != nullptr) {
1641 tty->print("find_node_by_idx: " INTPTR_FORMAT " and " INTPTR_FORMAT " both have idx==%d\n",
1642 (uintptr_t)result, (uintptr_t)n, idx);
1643 }
1644 result = n;
1645 }
1646 };
1647 visit_nodes(start, callback, traverse_output, only_ctrl);
1648 return result;
1649 }
1650
1651 int node_idx_cmp(const Node** n1, const Node** n2) {
1652 return (*n1)->_idx - (*n2)->_idx;
1653 }
1654
1655 void find_nodes_by_name(Node* start, const char* name) {
1656 ResourceMark rm;
1657 GrowableArray<const Node*> ns;
1658 auto callback = [&] (const Node* n) {
1659 if (StringUtils::is_star_match(name, n->Name())) {
1660 ns.push(n);
1661 }
1662 };
1663 visit_nodes(start, callback, true, false);
1664 ns.sort(node_idx_cmp);
1665 for (int i = 0; i < ns.length(); i++) {
1666 ns.at(i)->dump();
1667 }
1668 }
1669
1670 void find_nodes_by_dump(Node* start, const char* pattern) {
1671 ResourceMark rm;
1672 GrowableArray<const Node*> ns;
1673 auto callback = [&] (const Node* n) {
1674 stringStream stream;
1675 n->dump("", false, &stream);
1676 if (StringUtils::is_star_match(pattern, stream.base())) {
1677 ns.push(n);
1678 }
1679 };
1680 visit_nodes(start, callback, true, false);
1681 ns.sort(node_idx_cmp);
1682 for (int i = 0; i < ns.length(); i++) {
1683 ns.at(i)->dump();
1684 }
1685 }
1686
1687 // call from debugger: find node with name pattern in new/current graph
1688 // name can contain "*" in match pattern to match any characters
1689 // the matching is case insensitive
1690 void find_nodes_by_name(const char* name) {
1691 Node* root = Compile::current()->root();
1692 find_nodes_by_name(root, name);
1693 }
1694
1695 // call from debugger: find node with name pattern in old graph
1696 // name can contain "*" in match pattern to match any characters
1697 // the matching is case insensitive
1698 void find_old_nodes_by_name(const char* name) {
1699 Node* root = old_root();
1700 find_nodes_by_name(root, name);
1701 }
1702
1703 // call from debugger: find node with dump pattern in new/current graph
1704 // can contain "*" in match pattern to match any characters
1705 // the matching is case insensitive
1706 void find_nodes_by_dump(const char* pattern) {
1707 Node* root = Compile::current()->root();
1708 find_nodes_by_dump(root, pattern);
1709 }
1710
1711 // call from debugger: find node with name pattern in old graph
1712 // can contain "*" in match pattern to match any characters
1713 // the matching is case insensitive
1714 void find_old_nodes_by_dump(const char* pattern) {
1715 Node* root = old_root();
1716 find_nodes_by_dump(root, pattern);
1717 }
1718
1719 // Call this from debugger, search in same graph as n:
1720 Node* find_node(Node* n, const int idx) {
1721 return n->find(idx);
1722 }
1723
1724 // Call this from debugger, search in new nodes:
1725 Node* find_node(const int idx) {
1726 return Compile::current()->root()->find(idx);
1727 }
1728
1729 // Call this from debugger, search in old nodes:
1730 Node* find_old_node(const int idx) {
1731 Node* root = old_root();
1732 return (root == nullptr) ? nullptr : root->find(idx);
1733 }
1734
1735 // Call this from debugger, search in same graph as n:
1736 Node* find_ctrl(Node* n, const int idx) {
1737 return n->find_ctrl(idx);
1738 }
1739
1740 // Call this from debugger, search in new nodes:
1741 Node* find_ctrl(const int idx) {
1742 return Compile::current()->root()->find_ctrl(idx);
1743 }
1744
1745 // Call this from debugger, search in old nodes:
1746 Node* find_old_ctrl(const int idx) {
1747 Node* root = old_root();
1748 return (root == nullptr) ? nullptr : root->find_ctrl(idx);
1749 }
1750
1751 //------------------------------find_ctrl--------------------------------------
1752 // Find an ancestor to this node in the control history with given _idx
1753 Node* Node::find_ctrl(int idx) {
1754 return find(idx, true);
1755 }
1756
1757 //------------------------------find-------------------------------------------
1758 // Tries to find the node with the index |idx| starting from this node. If idx is negative,
1759 // the search also includes forward (out) edges. Returns null if not found.
1760 // If only_ctrl is set, the search will only be done on control nodes. Returns null if
1761 // not found or if the node to be found is not a control node (search will not find it).
1762 Node* Node::find(const int idx, bool only_ctrl) {
1763 ResourceMark rm;
1764 return find_node_by_idx(this, abs(idx), (idx < 0), only_ctrl);
1765 }
1766
1767 class PrintBFS {
1768 public:
1769 PrintBFS(const Node* start, const int max_distance, const Node* target, const char* options, outputStream* st)
1770 : _start(start), _max_distance(max_distance), _target(target), _options(options), _output(st),
1771 _dcc(this), _info_uid(cmpkey, hashkey) {}
1772
1773 void run();
1774 private:
1775 // pipeline steps
1776 bool configure();
1777 void collect();
1778 void select();
1779 void select_all();
1780 void select_all_paths();
1781 void select_shortest_path();
1782 void sort();
1783 void print();
1784
1785 // inputs
1786 const Node* _start;
1787 const int _max_distance;
1788 const Node* _target;
1789 const char* _options;
1790 outputStream* _output;
1791
1792 // options
1793 bool _traverse_inputs = false;
1794 bool _traverse_outputs = false;
1795 struct Filter {
1796 bool _control = false;
1797 bool _memory = false;
1798 bool _data = false;
1799 bool _mixed = false;
1800 bool _other = false;
1801 bool is_empty() const {
1802 return !(_control || _memory || _data || _mixed || _other);
1803 }
1804 void set_all() {
1805 _control = true;
1806 _memory = true;
1807 _data = true;
1808 _mixed = true;
1809 _other = true;
1810 }
1811 // Check if the filter accepts the node. Go by the type categories, but also all CFG nodes
1812 // are considered to have control.
1813 bool accepts(const Node* n) {
1814 const Type* t = n->bottom_type();
1815 return ( _data && t->has_category(Type::Category::Data) ) ||
1816 ( _memory && t->has_category(Type::Category::Memory) ) ||
1817 ( _mixed && t->has_category(Type::Category::Mixed) ) ||
1818 ( _control && (t->has_category(Type::Category::Control) || n->is_CFG()) ) ||
1819 ( _other && t->has_category(Type::Category::Other) );
1820 }
1821 };
1822 Filter _filter_visit;
1823 Filter _filter_boundary;
1824 bool _sort_idx = false;
1825 bool _all_paths = false;
1826 bool _use_color = false;
1827 bool _print_blocks = false;
1828 bool _print_old = false;
1829 bool _dump_only = false;
1830 void print_options_help(bool print_examples);
1831 bool parse_options();
1832
1833 public:
1834 class DumpConfigColored : public Node::DumpConfig {
1835 public:
1836 DumpConfigColored(PrintBFS* bfs) : _bfs(bfs) {};
1837 virtual void pre_dump(outputStream* st, const Node* n);
1838 virtual void post_dump(outputStream* st);
1839 private:
1840 PrintBFS* _bfs;
1841 };
1842 private:
1843 DumpConfigColored _dcc;
1844
1845 // node info
1846 static Node* old_node(const Node* n); // mach node -> prior IR node
1847 void print_node_idx(const Node* n);
1848 void print_block_id(const Block* b);
1849 void print_node_block(const Node* n); // _pre_order, head idx, _idom, _dom_depth
1850
1851 // traversal data structures
1852 GrowableArray<const Node*> _worklist; // BFS queue
1853 void maybe_traverse(const Node* src, const Node* dst);
1854
1855 // node info annotation
1856 class Info {
1857 public:
1858 Info() : Info(nullptr, 0) {};
1859 Info(const Node* node, int distance)
1860 : _node(node), _distance_from_start(distance) {};
1861 const Node* node() const { return _node; };
1862 int distance() const { return _distance_from_start; };
1863 int distance_from_target() const { return _distance_from_target; }
1864 void set_distance_from_target(int d) { _distance_from_target = d; }
1865 GrowableArray<const Node*> edge_bwd; // pointing toward _start
1866 bool is_marked() const { return _mark; } // marked to keep during select
1867 void set_mark() { _mark = true; }
1868 private:
1869 const Node* _node;
1870 int _distance_from_start; // distance from _start
1871 int _distance_from_target = 0; // distance from _target if _all_paths
1872 bool _mark = false;
1873 };
1874 Dict _info_uid; // Node -> uid
1875 GrowableArray<Info> _info; // uid -> info
1876
1877 Info* find_info(const Node* n) {
1878 size_t uid = (size_t)_info_uid[n];
1879 if (uid == 0) {
1880 return nullptr;
1881 }
1882 return &_info.at((int)uid);
1883 }
1884
1885 void make_info(const Node* node, const int distance) {
1886 assert(find_info(node) == nullptr, "node does not yet have info");
1887 size_t uid = _info.length() + 1;
1888 _info_uid.Insert((void*)node, (void*)uid);
1889 _info.at_put_grow((int)uid, Info(node, distance));
1890 assert(find_info(node)->node() == node, "stored correct node");
1891 };
1892
1893 // filled by sort, printed by print
1894 GrowableArray<const Node*> _print_list;
1895
1896 // print header + node table
1897 void print_header() const;
1898 void print_node(const Node* n);
1899 };
1900
1901 void PrintBFS::run() {
1902 if (!configure()) {
1903 return;
1904 }
1905 collect();
1906 select();
1907 sort();
1908 print();
1909 }
1910
1911 // set up configuration for BFS and print
1912 bool PrintBFS::configure() {
1913 if (_max_distance < 0) {
1914 _output->print_cr("dump_bfs: max_distance must be non-negative!");
1915 return false;
1916 }
1917 return parse_options();
1918 }
1919
1920 // BFS traverse according to configuration, fill worklist and info
1921 void PrintBFS::collect() {
1922 maybe_traverse(_start, _start);
1923 int pos = 0;
1924 while (pos < _worklist.length()) {
1925 const Node* n = _worklist.at(pos++); // next node to traverse
1926 Info* info = find_info(n);
1927 if (!_filter_visit.accepts(n) && n != _start) {
1928 continue; // we hit boundary, do not traverse further
1929 }
1930 if (n != _start && n->is_Root()) {
1931 continue; // traversing through root node would lead to unrelated nodes
1932 }
1933 if (_traverse_inputs && _max_distance > info->distance()) {
1934 for (uint i = 0; i < n->req(); i++) {
1935 maybe_traverse(n, n->in(i));
1936 }
1937 }
1938 if (_traverse_outputs && _max_distance > info->distance()) {
1939 for (uint i = 0; i < n->outcnt(); i++) {
1940 maybe_traverse(n, n->raw_out(i));
1941 }
1942 }
1943 }
1944 }
1945
1946 // go through work list, mark those that we want to print
1947 void PrintBFS::select() {
1948 if (_target == nullptr ) {
1949 select_all();
1950 } else {
1951 if (find_info(_target) == nullptr) {
1952 _output->print_cr("Could not find target in BFS.");
1953 return;
1954 }
1955 if (_all_paths) {
1956 select_all_paths();
1957 } else {
1958 select_shortest_path();
1959 }
1960 }
1961 }
1962
1963 // take all nodes from BFS
1964 void PrintBFS::select_all() {
1965 for (int i = 0; i < _worklist.length(); i++) {
1966 const Node* n = _worklist.at(i);
1967 Info* info = find_info(n);
1968 info->set_mark();
1969 }
1970 }
1971
1972 // traverse backward from target, along edges found in BFS
1973 void PrintBFS::select_all_paths() {
1974 int pos = 0;
1975 GrowableArray<const Node*> backtrace;
1976 // start from target
1977 backtrace.push(_target);
1978 find_info(_target)->set_mark();
1979 // traverse backward
1980 while (pos < backtrace.length()) {
1981 const Node* n = backtrace.at(pos++);
1982 Info* info = find_info(n);
1983 for (int i = 0; i < info->edge_bwd.length(); i++) {
1984 // all backward edges
1985 const Node* back = info->edge_bwd.at(i);
1986 Info* back_info = find_info(back);
1987 if (!back_info->is_marked()) {
1988 // not yet found this on way back.
1989 back_info->set_distance_from_target(info->distance_from_target() + 1);
1990 if (back_info->distance_from_target() + back_info->distance() <= _max_distance) {
1991 // total distance is small enough
1992 back_info->set_mark();
1993 backtrace.push(back);
1994 }
1995 }
1996 }
1997 }
1998 }
1999
2000 void PrintBFS::select_shortest_path() {
2001 const Node* current = _target;
2002 while (true) {
2003 Info* info = find_info(current);
2004 info->set_mark();
2005 if (current == _start) {
2006 break;
2007 }
2008 // first edge -> leads us one step closer to _start
2009 current = info->edge_bwd.at(0);
2010 }
2011 }
2012
2013 // go through worklist in desired order, put the marked ones in print list
2014 void PrintBFS::sort() {
2015 if (_traverse_inputs && !_traverse_outputs) {
2016 // reverse order
2017 for (int i = _worklist.length() - 1; i >= 0; i--) {
2018 const Node* n = _worklist.at(i);
2019 Info* info = find_info(n);
2020 if (info->is_marked()) {
2021 _print_list.push(n);
2022 }
2023 }
2024 } else {
2025 // same order as worklist
2026 for (int i = 0; i < _worklist.length(); i++) {
2027 const Node* n = _worklist.at(i);
2028 Info* info = find_info(n);
2029 if (info->is_marked()) {
2030 _print_list.push(n);
2031 }
2032 }
2033 }
2034 if (_sort_idx) {
2035 _print_list.sort(node_idx_cmp);
2036 }
2037 }
2038
2039 // go through printlist and print
2040 void PrintBFS::print() {
2041 if (_print_list.length() > 0 ) {
2042 print_header();
2043 for (int i = 0; i < _print_list.length(); i++) {
2044 const Node* n = _print_list.at(i);
2045 print_node(n);
2046 }
2047 } else {
2048 _output->print_cr("No nodes to print.");
2049 }
2050 }
2051
2052 void PrintBFS::print_options_help(bool print_examples) {
2053 _output->print_cr("Usage: node->dump_bfs(int max_distance, Node* target, char* options)");
2054 _output->print_cr("");
2055 _output->print_cr("Use cases:");
2056 _output->print_cr(" BFS traversal: no target required");
2057 _output->print_cr(" shortest path: set target");
2058 _output->print_cr(" all paths: set target and put 'A' in options");
2059 _output->print_cr(" detect loop: subcase of all paths, have start==target");
2060 _output->print_cr("");
2061 _output->print_cr("Arguments:");
2062 _output->print_cr(" this/start: staring point of BFS");
2063 _output->print_cr(" target:");
2064 _output->print_cr(" if null: simple BFS");
2065 _output->print_cr(" else: shortest path or all paths between this/start and target");
2066 _output->print_cr(" options:");
2067 _output->print_cr(" if null: same as \"cdmox@B\"");
2068 _output->print_cr(" else: use combination of following characters");
2069 _output->print_cr(" h: display this help info");
2070 _output->print_cr(" H: display this help info, with examples");
2071 _output->print_cr(" +: traverse in-edges (on if neither + nor -)");
2072 _output->print_cr(" -: traverse out-edges");
2073 _output->print_cr(" c: visit control nodes");
2074 _output->print_cr(" d: visit data nodes");
2075 _output->print_cr(" m: visit memory nodes");
2076 _output->print_cr(" o: visit other nodes");
2077 _output->print_cr(" x: visit mixed nodes");
2078 _output->print_cr(" C: boundary control nodes");
2079 _output->print_cr(" D: boundary data nodes");
2080 _output->print_cr(" M: boundary memory nodes");
2081 _output->print_cr(" O: boundary other nodes");
2082 _output->print_cr(" X: boundary mixed nodes");
2083 _output->print_cr(" #: display node category in color (not supported in all terminals)");
2084 _output->print_cr(" S: sort displayed nodes by node idx");
2085 _output->print_cr(" A: all paths (not just shortest path to target)");
2086 _output->print_cr(" @: print old nodes - before matching (if available)");
2087 _output->print_cr(" B: print scheduling blocks (if available)");
2088 _output->print_cr(" $: dump only, no header, no other columns");
2089 _output->print_cr("");
2090 _output->print_cr("recursively follow edges to nodes with permitted visit types,");
2091 _output->print_cr("on the boundary additionally display nodes allowed in boundary types");
2092 _output->print_cr("Note: the categories can be overlapping. For example a mixed node");
2093 _output->print_cr(" can contain control and memory output. Some from the other");
2094 _output->print_cr(" category are also control (Halt, Return, etc).");
2095 _output->print_cr("");
2096 _output->print_cr("output columns:");
2097 _output->print_cr(" dist: BFS distance to this/start");
2098 _output->print_cr(" apd: all paths distance (d_outputart + d_target)");
2099 _output->print_cr(" block: block identifier, based on _pre_order");
2100 _output->print_cr(" head: first node in block");
2101 _output->print_cr(" idom: head node of idom block");
2102 _output->print_cr(" depth: depth of block (_dom_depth)");
2103 _output->print_cr(" old: old IR node - before matching");
2104 _output->print_cr(" dump: node->dump()");
2105 _output->print_cr("");
2106 _output->print_cr("Note: if none of the \"cmdxo\" characters are in the options string");
2107 _output->print_cr(" then we set all of them.");
2108 _output->print_cr(" This allows for short strings like \"#\" for colored input traversal");
2109 _output->print_cr(" or \"-#\" for colored output traversal.");
2110 if (print_examples) {
2111 _output->print_cr("");
2112 _output->print_cr("Examples:");
2113 _output->print_cr(" if->dump_bfs(10, 0, \"+cxo\")");
2114 _output->print_cr(" starting at some if node, traverse inputs recursively");
2115 _output->print_cr(" only along control (mixed and other can also be control)");
2116 _output->print_cr(" phi->dump_bfs(5, 0, \"-dxo\")");
2117 _output->print_cr(" starting at phi node, traverse outputs recursively");
2118 _output->print_cr(" only along data (mixed and other can also have data flow)");
2119 _output->print_cr(" find_node(385)->dump_bfs(3, 0, \"cdmox+#@B\")");
2120 _output->print_cr(" find inputs of node 385, up to 3 nodes up (+)");
2121 _output->print_cr(" traverse all nodes (cdmox), use colors (#)");
2122 _output->print_cr(" display old nodes and blocks, if they exist");
2123 _output->print_cr(" useful call to start with");
2124 _output->print_cr(" find_node(102)->dump_bfs(10, 0, \"dCDMOX-\")");
2125 _output->print_cr(" find non-data dependencies of a data node");
2126 _output->print_cr(" follow data node outputs until we find another category");
2127 _output->print_cr(" node as the boundary");
2128 _output->print_cr(" x->dump_bfs(10, y, 0)");
2129 _output->print_cr(" find shortest path from x to y, along any edge or node");
2130 _output->print_cr(" will not find a path if it is longer than 10");
2131 _output->print_cr(" useful to find how x and y are related");
2132 _output->print_cr(" find_node(741)->dump_bfs(20, find_node(746), \"c+\")");
2133 _output->print_cr(" find shortest control path between two nodes");
2134 _output->print_cr(" find_node(741)->dump_bfs(8, find_node(746), \"cdmox+A\")");
2135 _output->print_cr(" find all paths (A) between two nodes of length at most 8");
2136 _output->print_cr(" find_node(741)->dump_bfs(7, find_node(741), \"c+A\")");
2137 _output->print_cr(" find all control loops for this node");
2138 }
2139 }
2140
2141 bool PrintBFS::parse_options() {
2142 if (_options == nullptr) {
2143 _options = "cdmox@B"; // default options
2144 }
2145 size_t len = strlen(_options);
2146 for (size_t i = 0; i < len; i++) {
2147 switch (_options[i]) {
2148 case '+':
2149 _traverse_inputs = true;
2150 break;
2151 case '-':
2152 _traverse_outputs = true;
2153 break;
2154 case 'c':
2155 _filter_visit._control = true;
2156 break;
2157 case 'm':
2158 _filter_visit._memory = true;
2159 break;
2160 case 'd':
2161 _filter_visit._data = true;
2162 break;
2163 case 'x':
2164 _filter_visit._mixed = true;
2165 break;
2166 case 'o':
2167 _filter_visit._other = true;
2168 break;
2169 case 'C':
2170 _filter_boundary._control = true;
2171 break;
2172 case 'M':
2173 _filter_boundary._memory = true;
2174 break;
2175 case 'D':
2176 _filter_boundary._data = true;
2177 break;
2178 case 'X':
2179 _filter_boundary._mixed = true;
2180 break;
2181 case 'O':
2182 _filter_boundary._other = true;
2183 break;
2184 case 'S':
2185 _sort_idx = true;
2186 break;
2187 case 'A':
2188 _all_paths = true;
2189 break;
2190 case '#':
2191 _use_color = true;
2192 break;
2193 case 'B':
2194 _print_blocks = true;
2195 break;
2196 case '@':
2197 _print_old = true;
2198 break;
2199 case '$':
2200 _dump_only = true;
2201 break;
2202 case 'h':
2203 print_options_help(false);
2204 return false;
2205 case 'H':
2206 print_options_help(true);
2207 return false;
2208 default:
2209 _output->print_cr("dump_bfs: Unrecognized option \'%c\'", _options[i]);
2210 _output->print_cr("for help, run: find_node(0)->dump_bfs(0,0,\"H\")");
2211 return false;
2212 }
2213 }
2214 if (!_traverse_inputs && !_traverse_outputs) {
2215 _traverse_inputs = true;
2216 }
2217 if (_filter_visit.is_empty()) {
2218 _filter_visit.set_all();
2219 }
2220 Compile* C = Compile::current();
2221 _print_old &= (C->matcher() != nullptr); // only show old if there are new
2222 _print_blocks &= (C->cfg() != nullptr); // only show blocks if available
2223 return true;
2224 }
2225
2226 void PrintBFS::DumpConfigColored::pre_dump(outputStream* st, const Node* n) {
2227 if (!_bfs->_use_color) {
2228 return;
2229 }
2230 Info* info = _bfs->find_info(n);
2231 if (info == nullptr || !info->is_marked()) {
2232 return;
2233 }
2234
2235 const Type* t = n->bottom_type();
2236 switch (t->category()) {
2237 case Type::Category::Data:
2238 st->print("\u001b[34m");
2239 break;
2240 case Type::Category::Memory:
2241 st->print("\u001b[32m");
2242 break;
2243 case Type::Category::Mixed:
2244 st->print("\u001b[35m");
2245 break;
2246 case Type::Category::Control:
2247 st->print("\u001b[31m");
2248 break;
2249 case Type::Category::Other:
2250 st->print("\u001b[33m");
2251 break;
2252 case Type::Category::Undef:
2253 n->dump();
2254 assert(false, "category undef ??");
2255 break;
2256 default:
2257 n->dump();
2258 assert(false, "not covered");
2259 break;
2260 }
2261 }
2262
2263 void PrintBFS::DumpConfigColored::post_dump(outputStream* st) {
2264 if (!_bfs->_use_color) {
2265 return;
2266 }
2267 st->print("\u001b[0m"); // white
2268 }
2269
2270 Node* PrintBFS::old_node(const Node* n) {
2271 Compile* C = Compile::current();
2272 if (C->matcher() == nullptr || !C->node_arena()->contains(n)) {
2273 return (Node*)nullptr;
2274 } else {
2275 return C->matcher()->find_old_node(n);
2276 }
2277 }
2278
2279 void PrintBFS::print_node_idx(const Node* n) {
2280 Compile* C = Compile::current();
2281 char buf[30];
2282 if (n == nullptr) {
2283 os::snprintf_checked(buf, sizeof(buf), "_"); // null
2284 } else if (C->node_arena()->contains(n)) {
2285 os::snprintf_checked(buf, sizeof(buf), "%d", n->_idx); // new node
2286 } else {
2287 os::snprintf_checked(buf, sizeof(buf), "o%d", n->_idx); // old node
2288 }
2289 _output->print("%6s", buf);
2290 }
2291
2292 void PrintBFS::print_block_id(const Block* b) {
2293 Compile* C = Compile::current();
2294 char buf[30];
2295 os::snprintf_checked(buf, sizeof(buf), "B%d", b->_pre_order);
2296 _output->print("%7s", buf);
2297 }
2298
2299 void PrintBFS::print_node_block(const Node* n) {
2300 Compile* C = Compile::current();
2301 Block* b = C->node_arena()->contains(n)
2302 ? C->cfg()->get_block_for_node(n)
2303 : nullptr; // guard against old nodes
2304 if (b == nullptr) {
2305 _output->print(" _"); // Block
2306 _output->print(" _"); // head
2307 _output->print(" _"); // idom
2308 _output->print(" _"); // depth
2309 } else {
2310 print_block_id(b);
2311 print_node_idx(b->head());
2312 if (b->_idom) {
2313 print_node_idx(b->_idom->head());
2314 } else {
2315 _output->print(" _"); // idom
2316 }
2317 _output->print("%6d ", b->_dom_depth);
2318 }
2319 }
2320
2321 // filter, and add to worklist, add info, note traversal edges
2322 void PrintBFS::maybe_traverse(const Node* src, const Node* dst) {
2323 if (dst != nullptr &&
2324 (_filter_visit.accepts(dst) ||
2325 _filter_boundary.accepts(dst) ||
2326 dst == _start)) { // correct category or start?
2327 if (find_info(dst) == nullptr) {
2328 // never visited - set up info
2329 _worklist.push(dst);
2330 int d = 0;
2331 if (dst != _start) {
2332 d = find_info(src)->distance() + 1;
2333 }
2334 make_info(dst, d);
2335 }
2336 if (src != dst) {
2337 // traversal edges useful during select
2338 find_info(dst)->edge_bwd.push(src);
2339 }
2340 }
2341 }
2342
2343 void PrintBFS::print_header() const {
2344 if (_dump_only) {
2345 return; // no header in dump only mode
2346 }
2347 _output->print("dist"); // distance
2348 if (_all_paths) {
2349 _output->print(" apd"); // all paths distance
2350 }
2351 if (_print_blocks) {
2352 _output->print(" [block head idom depth]"); // block
2353 }
2354 if (_print_old) {
2355 _output->print(" old"); // old node
2356 }
2357 _output->print(" dump\n"); // node dump
2358 _output->print_cr("---------------------------------------------");
2359 }
2360
2361 void PrintBFS::print_node(const Node* n) {
2362 if (_dump_only) {
2363 n->dump("\n", false, _output, &_dcc);
2364 return;
2365 }
2366 _output->print("%4d", find_info(n)->distance());// distance
2367 if (_all_paths) {
2368 Info* info = find_info(n);
2369 int apd = info->distance() + info->distance_from_target();
2370 _output->print("%4d", apd); // all paths distance
2371 }
2372 if (_print_blocks) {
2373 print_node_block(n); // block
2374 }
2375 if (_print_old) {
2376 print_node_idx(old_node(n)); // old node
2377 }
2378 _output->print(" ");
2379 n->dump("\n", false, _output, &_dcc); // node dump
2380 }
2381
2382 //------------------------------dump_bfs--------------------------------------
2383 // Call this from debugger
2384 // Useful for BFS traversal, shortest path, all path, loop detection, etc
2385 // Designed to be more readable, and provide additional info
2386 // To find all options, run:
2387 // find_node(0)->dump_bfs(0,0,"H")
2388 void Node::dump_bfs(const int max_distance, Node* target, const char* options) const {
2389 dump_bfs(max_distance, target, options, tty);
2390 }
2391
2392 // Used to dump to stream.
2393 void Node::dump_bfs(const int max_distance, Node* target, const char* options, outputStream* st) const {
2394 PrintBFS bfs(this, max_distance, target, options, st);
2395 bfs.run();
2396 }
2397
2398 // Call this from debugger, with default arguments
2399 void Node::dump_bfs(const int max_distance) const {
2400 dump_bfs(max_distance, nullptr, nullptr);
2401 }
2402
2403 // -----------------------------dump_idx---------------------------------------
2404 void Node::dump_idx(bool align, outputStream* st, DumpConfig* dc) const {
2405 if (dc != nullptr) {
2406 dc->pre_dump(st, this);
2407 }
2408 Compile* C = Compile::current();
2409 bool is_new = C->node_arena()->contains(this);
2410 if (align) { // print prefix empty spaces$
2411 // +1 for leading digit, +1 for "o"
2412 uint max_width = static_cast<uint>(log10(static_cast<double>(C->unique()))) + 2;
2413 // +1 for leading digit, maybe +1 for "o"
2414 uint width = static_cast<uint>(log10(static_cast<double>(_idx))) + 1 + (is_new ? 0 : 1);
2415 while (max_width > width) {
2416 st->print(" ");
2417 width++;
2418 }
2419 }
2420 if (!is_new) {
2421 st->print("o");
2422 }
2423 st->print("%d", _idx);
2424 if (dc != nullptr) {
2425 dc->post_dump(st);
2426 }
2427 }
2428
2429 // -----------------------------dump_name--------------------------------------
2430 void Node::dump_name(outputStream* st, DumpConfig* dc) const {
2431 if (dc != nullptr) {
2432 dc->pre_dump(st, this);
2433 }
2434 st->print("%s", Name());
2435 if (dc != nullptr) {
2436 dc->post_dump(st);
2437 }
2438 }
2439
2440 // -----------------------------Name-------------------------------------------
2441 extern const char *NodeClassNames[];
2442 const char *Node::Name() const { return NodeClassNames[Opcode()]; }
2443
2444 static bool is_disconnected(const Node* n) {
2445 for (uint i = 0; i < n->req(); i++) {
2446 if (n->in(i) != nullptr) return false;
2447 }
2448 return true;
2449 }
2450
2451 #ifdef ASSERT
2452 void Node::dump_orig(outputStream *st, bool print_key) const {
2453 Compile* C = Compile::current();
2454 Node* orig = _debug_orig;
2455 if (not_a_node(orig)) orig = nullptr;
2456 if (orig != nullptr && !C->node_arena()->contains(orig)) orig = nullptr;
2457 if (orig == nullptr) return;
2458 if (print_key) {
2459 st->print(" !orig=");
2460 }
2461 Node* fast = orig->debug_orig(); // tortoise & hare algorithm to detect loops
2462 if (not_a_node(fast)) fast = nullptr;
2463 while (orig != nullptr) {
2464 bool discon = is_disconnected(orig); // if discon, print [123] else 123
2465 if (discon) st->print("[");
2466 if (!Compile::current()->node_arena()->contains(orig))
2467 st->print("o");
2468 st->print("%d", orig->_idx);
2469 if (discon) st->print("]");
2470 orig = orig->debug_orig();
2471 if (not_a_node(orig)) orig = nullptr;
2472 if (orig != nullptr && !C->node_arena()->contains(orig)) orig = nullptr;
2473 if (orig != nullptr) st->print(",");
2474 if (fast != nullptr) {
2475 // Step fast twice for each single step of orig:
2476 fast = fast->debug_orig();
2477 if (not_a_node(fast)) fast = nullptr;
2478 if (fast != nullptr && fast != orig) {
2479 fast = fast->debug_orig();
2480 if (not_a_node(fast)) fast = nullptr;
2481 }
2482 if (fast == orig) {
2483 st->print("...");
2484 break;
2485 }
2486 }
2487 }
2488 }
2489
2490 void Node::set_debug_orig(Node* orig) {
2491 _debug_orig = orig;
2492 if (BreakAtNode == 0) return;
2493 if (not_a_node(orig)) orig = nullptr;
2494 int trip = 10;
2495 while (orig != nullptr) {
2496 if (orig->debug_idx() == BreakAtNode || (uintx)orig->_idx == BreakAtNode) {
2497 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=" UINT64_FORMAT " orig._idx=%d orig._debug_idx=" UINT64_FORMAT,
2498 this->_idx, this->debug_idx(), orig->_idx, orig->debug_idx());
2499 BREAKPOINT;
2500 }
2501 orig = orig->debug_orig();
2502 if (not_a_node(orig)) orig = nullptr;
2503 if (trip-- <= 0) break;
2504 }
2505 }
2506 #endif //ASSERT
2507
2508 //------------------------------dump------------------------------------------
2509 // Dump a Node
2510 void Node::dump(const char* suffix, bool mark, outputStream* st, DumpConfig* dc) const {
2511 Compile* C = Compile::current();
2512 bool is_new = C->node_arena()->contains(this);
2513 C->_in_dump_cnt++;
2514
2515 // idx mark name ===
2516 dump_idx(true, st, dc);
2517 st->print(mark ? " >" : " ");
2518 dump_name(st, dc);
2519 st->print(" === ");
2520
2521 // Dump the required and precedence inputs
2522 dump_req(st, dc);
2523 dump_prec(st, dc);
2524 // Dump the outputs
2525 dump_out(st, dc);
2526
2527 if (is_disconnected(this)) {
2528 #ifdef ASSERT
2529 st->print(" [" UINT64_FORMAT "]", debug_idx());
2530 dump_orig(st);
2531 #endif
2532 st->cr();
2533 C->_in_dump_cnt--;
2534 return; // don't process dead nodes
2535 }
2536
2537 if (C->clone_map().value(_idx) != 0) {
2538 C->clone_map().dump(_idx, st);
2539 }
2540 // Dump node-specific info
2541 dump_spec(st);
2542 #ifdef ASSERT
2543 // Dump the non-reset _debug_idx
2544 if (Verbose && WizardMode) {
2545 st->print(" [" UINT64_FORMAT "]", debug_idx());
2546 }
2547 #endif
2548
2549 const Type *t = bottom_type();
2550
2551 if (t != nullptr && (t->isa_instptr() || t->isa_instklassptr())) {
2552 const TypeInstPtr *toop = t->isa_instptr();
2553 const TypeInstKlassPtr *tkls = t->isa_instklassptr();
2554 if (toop) {
2555 st->print(" Oop:");
2556 } else if (tkls) {
2557 st->print(" Klass:");
2558 }
2559 t->dump_on(st);
2560 } else if (t == Type::MEMORY) {
2561 st->print(" Memory:");
2562 MemNode::dump_adr_type(this, adr_type(), st);
2563 } else if (Verbose || WizardMode) {
2564 st->print(" Type:");
2565 if (t) {
2566 t->dump_on(st);
2567 } else {
2568 st->print("no type");
2569 }
2570 } else if (t->isa_vect() && this->is_MachSpillCopy()) {
2571 // Dump MachSpillcopy vector type.
2572 t->dump_on(st);
2573 }
2574 if (is_new) {
2575 DEBUG_ONLY(dump_orig(st));
2576 Node_Notes* nn = C->node_notes_at(_idx);
2577 if (nn != nullptr && !nn->is_clear()) {
2578 if (nn->jvms() != nullptr) {
2579 st->print(" !jvms:");
2580 nn->jvms()->dump_spec(st);
2581 }
2582 }
2583 }
2584 if (suffix) st->print("%s", suffix);
2585 C->_in_dump_cnt--;
2586 }
2587
2588 // call from debugger: dump node to tty with newline
2589 void Node::dump() const {
2590 dump("\n");
2591 }
2592
2593 //------------------------------dump_req--------------------------------------
2594 void Node::dump_req(outputStream* st, DumpConfig* dc) const {
2595 // Dump the required input edges
2596 for (uint i = 0; i < req(); i++) { // For all required inputs
2597 Node* d = in(i);
2598 if (d == nullptr) {
2599 st->print("_ ");
2600 } else if (not_a_node(d)) {
2601 st->print("not_a_node "); // uninitialized, sentinel, garbage, etc.
2602 } else {
2603 d->dump_idx(false, st, dc);
2604 st->print(" ");
2605 }
2606 }
2607 }
2608
2609
2610 //------------------------------dump_prec-------------------------------------
2611 void Node::dump_prec(outputStream* st, DumpConfig* dc) const {
2612 // Dump the precedence edges
2613 int any_prec = 0;
2614 for (uint i = req(); i < len(); i++) { // For all precedence inputs
2615 Node* p = in(i);
2616 if (p != nullptr) {
2617 if (!any_prec++) st->print(" |");
2618 if (not_a_node(p)) { st->print("not_a_node "); continue; }
2619 p->dump_idx(false, st, dc);
2620 st->print(" ");
2621 }
2622 }
2623 }
2624
2625 //------------------------------dump_out--------------------------------------
2626 void Node::dump_out(outputStream* st, DumpConfig* dc) const {
2627 // Delimit the output edges
2628 st->print(" [[ ");
2629 // Dump the output edges
2630 for (uint i = 0; i < _outcnt; i++) { // For all outputs
2631 Node* u = _out[i];
2632 if (u == nullptr) {
2633 st->print("_ ");
2634 } else if (not_a_node(u)) {
2635 st->print("not_a_node ");
2636 } else {
2637 u->dump_idx(false, st, dc);
2638 st->print(" ");
2639 }
2640 }
2641 st->print("]] ");
2642 }
2643
2644 //------------------------------dump-------------------------------------------
2645 // call from debugger: dump Node's inputs (or outputs if d negative)
2646 void Node::dump(int d) const {
2647 dump_bfs(abs(d), nullptr, (d > 0) ? "+$" : "-$");
2648 }
2649
2650 //------------------------------dump_ctrl--------------------------------------
2651 // call from debugger: dump Node's control inputs (or outputs if d negative)
2652 void Node::dump_ctrl(int d) const {
2653 dump_bfs(abs(d), nullptr, (d > 0) ? "+$c" : "-$c");
2654 }
2655
2656 //-----------------------------dump_compact------------------------------------
2657 void Node::dump_comp() const {
2658 this->dump_comp("\n");
2659 }
2660
2661 //-----------------------------dump_compact------------------------------------
2662 // Dump a Node in compact representation, i.e., just print its name and index.
2663 // Nodes can specify additional specifics to print in compact representation by
2664 // implementing dump_compact_spec.
2665 void Node::dump_comp(const char* suffix, outputStream *st) const {
2666 Compile* C = Compile::current();
2667 C->_in_dump_cnt++;
2668 st->print("%s(%d)", Name(), _idx);
2669 this->dump_compact_spec(st);
2670 if (suffix) {
2671 st->print("%s", suffix);
2672 }
2673 C->_in_dump_cnt--;
2674 }
2675
2676 // VERIFICATION CODE
2677 // Verify all nodes if verify_depth is negative
2678 void Node::verify(int verify_depth, VectorSet& visited, Node_List& worklist) {
2679 assert(verify_depth != 0, "depth should not be 0");
2680 Compile* C = Compile::current();
2681 uint last_index_on_current_depth = worklist.size() - 1;
2682 verify_depth--; // Visiting the first node on depth 1
2683 // Only add nodes to worklist if verify_depth is negative (visit all nodes) or greater than 0
2684 bool add_to_worklist = verify_depth != 0;
2685
2686 for (uint list_index = 0; list_index < worklist.size(); list_index++) {
2687 Node* n = worklist[list_index];
2688
2689 if (n->is_Con() && n->bottom_type() == Type::TOP) {
2690 if (C->cached_top_node() == nullptr) {
2691 C->set_cached_top_node((Node*)n);
2692 }
2693 assert(C->cached_top_node() == n, "TOP node must be unique");
2694 }
2695
2696 uint in_len = n->len();
2697 for (uint i = 0; i < in_len; i++) {
2698 Node* x = n->_in[i];
2699 if (!x || x->is_top()) {
2700 continue;
2701 }
2702
2703 // Verify my input has a def-use edge to me
2704 // Count use-def edges from n to x
2705 int cnt = 1;
2706 for (uint j = 0; j < i; j++) {
2707 if (n->_in[j] == x) {
2708 cnt++;
2709 break;
2710 }
2711 }
2712 if (cnt == 2) {
2713 // x is already checked as n's previous input, skip its duplicated def-use count checking
2714 continue;
2715 }
2716 for (uint j = i + 1; j < in_len; j++) {
2717 if (n->_in[j] == x) {
2718 cnt++;
2719 }
2720 }
2721
2722 // Count def-use edges from x to n
2723 uint max = x->_outcnt;
2724 for (uint k = 0; k < max; k++) {
2725 if (x->_out[k] == n) {
2726 cnt--;
2727 }
2728 }
2729 assert(cnt == 0, "mismatched def-use edge counts");
2730
2731 if (add_to_worklist && !visited.test_set(x->_idx)) {
2732 worklist.push(x);
2733 }
2734 }
2735
2736 if (verify_depth > 0 && list_index == last_index_on_current_depth) {
2737 // All nodes on this depth were processed and its inputs are on the worklist. Decrement verify_depth and
2738 // store the current last list index which is the last node in the list with the new depth. All nodes
2739 // added afterwards will have a new depth again. Stop adding new nodes if depth limit is reached (=0).
2740 verify_depth--;
2741 if (verify_depth == 0) {
2742 add_to_worklist = false;
2743 }
2744 last_index_on_current_depth = worklist.size() - 1;
2745 }
2746 }
2747 }
2748 #endif // not PRODUCT
2749
2750 //------------------------------Registers--------------------------------------
2751 // Do we Match on this edge index or not? Generally false for Control
2752 // and true for everything else. Weird for calls & returns.
2753 uint Node::match_edge(uint idx) const {
2754 return idx; // True for other than index 0 (control)
2755 }
2756
2757 // Register classes are defined for specific machines
2758 const RegMask &Node::out_RegMask() const {
2759 ShouldNotCallThis();
2760 return RegMask::Empty;
2761 }
2762
2763 const RegMask &Node::in_RegMask(uint) const {
2764 ShouldNotCallThis();
2765 return RegMask::Empty;
2766 }
2767
2768 void Node_Array::grow(uint i) {
2769 assert(_max > 0, "invariant");
2770 uint old = _max;
2771 _max = next_power_of_2(i);
2772 _nodes = (Node**)_a->Arealloc( _nodes, old*sizeof(Node*),_max*sizeof(Node*));
2773 Copy::zero_to_bytes( &_nodes[old], (_max-old)*sizeof(Node*) );
2774 }
2775
2776 void Node_Array::insert(uint i, Node* n) {
2777 if (_nodes[_max - 1]) {
2778 grow(_max);
2779 }
2780 Copy::conjoint_words_to_higher((HeapWord*)&_nodes[i], (HeapWord*)&_nodes[i + 1], ((_max - i - 1) * sizeof(Node*)));
2781 _nodes[i] = n;
2782 }
2783
2784 void Node_Array::remove(uint i) {
2785 Copy::conjoint_words_to_lower((HeapWord*)&_nodes[i + 1], (HeapWord*)&_nodes[i], ((_max - i - 1) * sizeof(Node*)));
2786 _nodes[_max - 1] = nullptr;
2787 }
2788
2789 void Node_Array::dump() const {
2790 #ifndef PRODUCT
2791 for (uint i = 0; i < _max; i++) {
2792 Node* nn = _nodes[i];
2793 if (nn != nullptr) {
2794 tty->print("%5d--> ",i); nn->dump();
2795 }
2796 }
2797 #endif
2798 }
2799
2800 //--------------------------is_iteratively_computed------------------------------
2801 // Operation appears to be iteratively computed (such as an induction variable)
2802 // It is possible for this operation to return false for a loop-varying
2803 // value, if it appears (by local graph inspection) to be computed by a simple conditional.
2804 bool Node::is_iteratively_computed() {
2805 if (ideal_reg()) { // does operation have a result register?
2806 for (uint i = 1; i < req(); i++) {
2807 Node* n = in(i);
2808 if (n != nullptr && n->is_Phi()) {
2809 for (uint j = 1; j < n->req(); j++) {
2810 if (n->in(j) == this) {
2811 return true;
2812 }
2813 }
2814 }
2815 }
2816 }
2817 return false;
2818 }
2819
2820 //--------------------------find_similar------------------------------
2821 // Return a node with opcode "opc" and same inputs as "this" if one can
2822 // be found; Otherwise return null;
2823 Node* Node::find_similar(int opc) {
2824 if (req() >= 2) {
2825 Node* def = in(1);
2826 if (def && def->outcnt() >= 2) {
2827 for (DUIterator_Fast dmax, i = def->fast_outs(dmax); i < dmax; i++) {
2828 Node* use = def->fast_out(i);
2829 if (use != this &&
2830 use->Opcode() == opc &&
2831 use->req() == req()) {
2832 uint j;
2833 for (j = 0; j < use->req(); j++) {
2834 if (use->in(j) != in(j)) {
2835 break;
2836 }
2837 }
2838 if (j == use->req()) {
2839 return use;
2840 }
2841 }
2842 }
2843 }
2844 }
2845 return nullptr;
2846 }
2847
2848
2849 //--------------------------unique_ctrl_out_or_null-------------------------
2850 // Return the unique control out if only one. Null if none or more than one.
2851 Node* Node::unique_ctrl_out_or_null() const {
2852 Node* found = nullptr;
2853 for (uint i = 0; i < outcnt(); i++) {
2854 Node* use = raw_out(i);
2855 if (use->is_CFG() && use != this) {
2856 if (found != nullptr) {
2857 return nullptr;
2858 }
2859 found = use;
2860 }
2861 }
2862 return found;
2863 }
2864
2865 //--------------------------unique_ctrl_out------------------------------
2866 // Return the unique control out. Asserts if none or more than one control out.
2867 Node* Node::unique_ctrl_out() const {
2868 Node* ctrl = unique_ctrl_out_or_null();
2869 assert(ctrl != nullptr, "control out is assumed to be unique");
2870 return ctrl;
2871 }
2872
2873 void Node::ensure_control_or_add_prec(Node* c) {
2874 if (in(0) == nullptr) {
2875 set_req(0, c);
2876 } else if (in(0) != c) {
2877 add_prec(c);
2878 }
2879 }
2880
2881 bool Node::is_dead_loop_safe() const {
2882 if (is_Phi()) {
2883 return true;
2884 }
2885 if (is_Proj() && in(0) == nullptr) {
2886 return true;
2887 }
2888 if ((_flags & (Flag_is_dead_loop_safe | Flag_is_Con)) != 0) {
2889 if (!is_Proj()) {
2890 return true;
2891 }
2892 if (in(0)->is_Allocate()) {
2893 return false;
2894 }
2895 // MemNode::can_see_stored_value() peeks through the boxing call
2896 if (in(0)->is_CallStaticJava() && in(0)->as_CallStaticJava()->is_boxing_method()) {
2897 return false;
2898 }
2899 return true;
2900 }
2901 return false;
2902 }
2903
2904 //=============================================================================
2905 //------------------------------yank-------------------------------------------
2906 // Find and remove
2907 void Node_List::yank( Node *n ) {
2908 uint i;
2909 for (i = 0; i < _cnt; i++) {
2910 if (_nodes[i] == n) {
2911 break;
2912 }
2913 }
2914
2915 if (i < _cnt) {
2916 _nodes[i] = _nodes[--_cnt];
2917 }
2918 }
2919
2920 //------------------------------dump-------------------------------------------
2921 void Node_List::dump() const {
2922 #ifndef PRODUCT
2923 for (uint i = 0; i < _cnt; i++) {
2924 if (_nodes[i]) {
2925 tty->print("%5d--> ", i);
2926 _nodes[i]->dump();
2927 }
2928 }
2929 #endif
2930 }
2931
2932 void Node_List::dump_simple() const {
2933 #ifndef PRODUCT
2934 for (uint i = 0; i < _cnt; i++) {
2935 if( _nodes[i] ) {
2936 tty->print(" %d", _nodes[i]->_idx);
2937 } else {
2938 tty->print(" null");
2939 }
2940 }
2941 #endif
2942 }
2943
2944 //=============================================================================
2945 //------------------------------remove-----------------------------------------
2946 void Unique_Node_List::remove(Node* n) {
2947 if (_in_worklist.test(n->_idx)) {
2948 for (uint i = 0; i < size(); i++) {
2949 if (_nodes[i] == n) {
2950 map(i, Node_List::pop());
2951 _in_worklist.remove(n->_idx);
2952 return;
2953 }
2954 }
2955 ShouldNotReachHere();
2956 }
2957 }
2958
2959 //-----------------------remove_useless_nodes----------------------------------
2960 // Remove useless nodes from worklist
2961 void Unique_Node_List::remove_useless_nodes(VectorSet &useful) {
2962 for (uint i = 0; i < size(); ++i) {
2963 Node *n = at(i);
2964 assert( n != nullptr, "Did not expect null entries in worklist");
2965 if (!useful.test(n->_idx)) {
2966 _in_worklist.remove(n->_idx);
2967 map(i, Node_List::pop());
2968 --i; // Visit popped node
2969 // If it was last entry, loop terminates since size() was also reduced
2970 }
2971 }
2972 }
2973
2974 //=============================================================================
2975 void Node_Stack::grow() {
2976 size_t old_top = pointer_delta(_inode_top,_inodes,sizeof(INode)); // save _top
2977 size_t old_max = pointer_delta(_inode_max,_inodes,sizeof(INode));
2978 size_t max = old_max << 1; // max * 2
2979 _inodes = REALLOC_ARENA_ARRAY(_a, INode, _inodes, old_max, max);
2980 _inode_max = _inodes + max;
2981 _inode_top = _inodes + old_top; // restore _top
2982 }
2983
2984 // Node_Stack is used to map nodes.
2985 Node* Node_Stack::find(uint idx) const {
2986 uint sz = size();
2987 for (uint i = 0; i < sz; i++) {
2988 if (idx == index_at(i)) {
2989 return node_at(i);
2990 }
2991 }
2992 return nullptr;
2993 }
2994
2995 //=============================================================================
2996 uint TypeNode::size_of() const { return sizeof(*this); }
2997 #ifndef PRODUCT
2998 void TypeNode::dump_spec(outputStream *st) const {
2999 if (!Verbose && !WizardMode) {
3000 // standard dump does this in Verbose and WizardMode
3001 st->print(" #"); _type->dump_on(st);
3002 }
3003 }
3004
3005 void TypeNode::dump_compact_spec(outputStream *st) const {
3006 st->print("#");
3007 _type->dump_on(st);
3008 }
3009 #endif
3010 uint TypeNode::hash() const {
3011 return Node::hash() + _type->hash();
3012 }
3013 bool TypeNode::cmp(const Node& n) const {
3014 return !Type::cmp(_type, ((TypeNode&)n)._type);
3015 }
3016 const Type* TypeNode::bottom_type() const { return _type; }
3017 const Type* TypeNode::Value(PhaseGVN* phase) const { return _type; }
3018
3019 //------------------------------ideal_reg--------------------------------------
3020 uint TypeNode::ideal_reg() const {
3021 return _type->ideal_reg();
3022 }