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 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
512 bs->register_potential_barrier_node(n);
513
514 n->set_idx(C->next_unique()); // Get new unique index as well
515 NOT_PRODUCT(n->_igv_idx = C->next_igv_idx());
516 debug_only( n->verify_construction() );
517 NOT_PRODUCT(nodes_created++);
518 // Do not patch over the debug_idx of a clone, because it makes it
519 // impossible to break on the clone's moment of creation.
520 //debug_only( n->set_debug_idx( debug_idx() ) );
521
522 C->copy_node_notes_to(n, (Node*) this);
523
524 // MachNode clone
525 uint nopnds;
526 if (this->is_Mach() && (nopnds = this->as_Mach()->num_opnds()) > 0) {
527 MachNode *mach = n->as_Mach();
528 MachNode *mthis = this->as_Mach();
529 // Get address of _opnd_array.
530 // It should be the same offset since it is the clone of this node.
531 MachOper **from = mthis->_opnds;
532 MachOper **to = (MachOper **)((size_t)(&mach->_opnds) +
533 pointer_delta((const void*)from,
534 (const void*)(&mthis->_opnds), 1));
535 mach->_opnds = to;
536 for ( uint i = 0; i < nopnds; ++i ) {
537 to[i] = from[i]->clone();
538 }
539 }
540 if (n->is_Call()) {
541 // CallGenerator is linked to the original node.
542 CallGenerator* cg = n->as_Call()->generator();
543 if (cg != nullptr) {
544 CallGenerator* cloned_cg = cg->with_call_node(n->as_Call());
545 n->as_Call()->set_generator(cloned_cg);
546
547 C->print_inlining_assert_ready();
548 C->print_inlining_move_to(cg);
549 C->print_inlining_update(cloned_cg);
550 }
551 }
552 if (n->is_SafePoint()) {
553 // Scalar replacement and macro expansion might modify the JVMState.
554 // Clone it to make sure it's not shared between SafePointNodes.
555 n->as_SafePoint()->clone_jvms(C);
556 n->as_SafePoint()->clone_replaced_nodes();
557 }
558 Compile::current()->record_modified_node(n);
559 return n; // Return the clone
560 }
561
562 //---------------------------setup_is_top--------------------------------------
563 // Call this when changing the top node, to reassert the invariants
564 // required by Node::is_top. See Compile::set_cached_top_node.
565 void Node::setup_is_top() {
566 if (this == (Node*)Compile::current()->top()) {
567 // This node has just become top. Kill its out array.
568 _outcnt = _outmax = 0;
569 _out = nullptr; // marker value for top
570 assert(is_top(), "must be top");
571 } else {
572 if (_out == nullptr) _out = NO_OUT_ARRAY;
573 assert(!is_top(), "must not be top");
574 }
575 }
576
577 //------------------------------~Node------------------------------------------
578 // Fancy destructor; eagerly attempt to reclaim Node numberings and storage
579 void Node::destruct(PhaseValues* phase) {
580 Compile* compile = (phase != nullptr) ? phase->C : Compile::current();
581 if (phase != nullptr && phase->is_IterGVN()) {
582 phase->is_IterGVN()->_worklist.remove(this);
583 }
584 // If this is the most recently created node, reclaim its index. Otherwise,
585 // record the node as dead to keep liveness information accurate.
586 if ((uint)_idx+1 == compile->unique()) {
587 compile->set_unique(compile->unique()-1);
588 } else {
589 compile->record_dead_node(_idx);
590 }
591 // Clear debug info:
592 Node_Notes* nn = compile->node_notes_at(_idx);
593 if (nn != nullptr) nn->clear();
594 // Walk the input array, freeing the corresponding output edges
595 _cnt = _max; // forget req/prec distinction
596 uint i;
597 for( i = 0; i < _max; i++ ) {
598 set_req(i, nullptr);
599 //assert(def->out(def->outcnt()-1) == (Node *)this,"bad def-use hacking in reclaim");
600 }
601 assert(outcnt() == 0, "deleting a node must not leave a dangling use");
602
603 if (is_macro()) {
604 compile->remove_macro_node(this);
605 }
606 if (is_expensive()) {
607 compile->remove_expensive_node(this);
608 }
609 if (Opcode() == Op_Opaque4) {
610 compile->remove_template_assertion_predicate_opaq(this);
611 }
612 if (for_post_loop_opts_igvn()) {
613 compile->remove_from_post_loop_opts_igvn(this);
614 }
615
616 if (is_SafePoint()) {
617 as_SafePoint()->delete_replaced_nodes();
618
619 if (is_CallStaticJava()) {
620 compile->remove_unstable_if_trap(as_CallStaticJava(), false);
621 }
622 }
623 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
624 bs->unregister_potential_barrier_node(this);
625
626 // See if the input array was allocated just prior to the object
627 int edge_size = _max*sizeof(void*);
628 int out_edge_size = _outmax*sizeof(void*);
629 char *in_array = ((char*)_in);
630 char *edge_end = in_array + edge_size;
631 char *out_array = (char*)(_out == NO_OUT_ARRAY? nullptr: _out);
632 int node_size = size_of();
633
634 #ifdef ASSERT
635 // We will not actually delete the storage, but we'll make the node unusable.
636 compile->remove_modified_node(this);
637 *(address*)this = badAddress; // smash the C++ vtbl, probably
638 _in = _out = (Node**) badAddress;
639 _max = _cnt = _outmax = _outcnt = 0;
640 #endif
641
642 // Free the output edge array
643 if (out_edge_size > 0) {
644 compile->node_arena()->Afree(out_array, out_edge_size);
645 }
646
647 // Free the input edge array and the node itself
648 if( edge_end == (char*)this ) {
649 // It was; free the input array and object all in one hit
650 #ifndef ASSERT
651 compile->node_arena()->Afree(in_array, edge_size+node_size);
652 #endif
653 } else {
654 // Free just the input array
655 compile->node_arena()->Afree(in_array, edge_size);
656
657 // Free just the object
658 #ifndef ASSERT
659 compile->node_arena()->Afree(this, node_size);
660 #endif
661 }
662 }
663
664 //------------------------------grow-------------------------------------------
665 // Grow the input array, making space for more edges
666 void Node::grow(uint len) {
667 Arena* arena = Compile::current()->node_arena();
668 uint new_max = _max;
669 if( new_max == 0 ) {
670 _max = 4;
671 _in = (Node**)arena->Amalloc(4*sizeof(Node*));
672 Node** to = _in;
673 to[0] = nullptr;
674 to[1] = nullptr;
675 to[2] = nullptr;
676 to[3] = nullptr;
677 return;
678 }
679 new_max = next_power_of_2(len);
680 // Trimming to limit allows a uint8 to handle up to 255 edges.
681 // Previously I was using only powers-of-2 which peaked at 128 edges.
682 //if( new_max >= limit ) new_max = limit-1;
683 _in = (Node**)arena->Arealloc(_in, _max*sizeof(Node*), new_max*sizeof(Node*));
684 Copy::zero_to_bytes(&_in[_max], (new_max-_max)*sizeof(Node*)); // null all new space
685 _max = new_max; // Record new max length
686 // This assertion makes sure that Node::_max is wide enough to
687 // represent the numerical value of new_max.
688 assert(_max == new_max && _max > len, "int width of _max is too small");
689 }
690
691 //-----------------------------out_grow----------------------------------------
692 // Grow the input array, making space for more edges
693 void Node::out_grow( uint len ) {
694 assert(!is_top(), "cannot grow a top node's out array");
695 Arena* arena = Compile::current()->node_arena();
696 uint new_max = _outmax;
697 if( new_max == 0 ) {
698 _outmax = 4;
699 _out = (Node **)arena->Amalloc(4*sizeof(Node*));
700 return;
701 }
702 new_max = next_power_of_2(len);
703 // Trimming to limit allows a uint8 to handle up to 255 edges.
704 // Previously I was using only powers-of-2 which peaked at 128 edges.
705 //if( new_max >= limit ) new_max = limit-1;
706 assert(_out != nullptr && _out != NO_OUT_ARRAY, "out must have sensible value");
707 _out = (Node**)arena->Arealloc(_out,_outmax*sizeof(Node*),new_max*sizeof(Node*));
708 //Copy::zero_to_bytes(&_out[_outmax], (new_max-_outmax)*sizeof(Node*)); // null all new space
709 _outmax = new_max; // Record new max length
710 // This assertion makes sure that Node::_max is wide enough to
711 // represent the numerical value of new_max.
712 assert(_outmax == new_max && _outmax > len, "int width of _outmax is too small");
713 }
714
715 #ifdef ASSERT
716 //------------------------------is_dead----------------------------------------
717 bool Node::is_dead() const {
718 // Mach and pinch point nodes may look like dead.
719 if( is_top() || is_Mach() || (Opcode() == Op_Node && _outcnt > 0) )
720 return false;
721 for( uint i = 0; i < _max; i++ )
722 if( _in[i] != nullptr )
723 return false;
724 return true;
725 }
726
727 bool Node::is_not_dead(const Node* n) {
728 return n == nullptr || !PhaseIterGVN::is_verify_def_use() || !(n->is_dead());
729 }
730
731 bool Node::is_reachable_from_root() const {
732 ResourceMark rm;
733 Unique_Node_List wq;
734 wq.push((Node*)this);
735 RootNode* root = Compile::current()->root();
736 for (uint i = 0; i < wq.size(); i++) {
737 Node* m = wq.at(i);
738 if (m == root) {
739 return true;
740 }
741 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
742 Node* u = m->fast_out(j);
743 wq.push(u);
744 }
745 }
746 return false;
747 }
748 #endif
749
750 //------------------------------is_unreachable---------------------------------
751 bool Node::is_unreachable(PhaseIterGVN &igvn) const {
752 assert(!is_Mach(), "doesn't work with MachNodes");
753 return outcnt() == 0 || igvn.type(this) == Type::TOP || (in(0) != nullptr && in(0)->is_top());
754 }
755
756 //------------------------------add_req----------------------------------------
757 // Add a new required input at the end
758 void Node::add_req( Node *n ) {
759 assert( is_not_dead(n), "can not use dead node");
760
761 // Look to see if I can move precedence down one without reallocating
762 if( (_cnt >= _max) || (in(_max-1) != nullptr) )
763 grow( _max+1 );
764
765 // Find a precedence edge to move
766 if( in(_cnt) != nullptr ) { // Next precedence edge is busy?
767 uint i;
768 for( i=_cnt; i<_max; i++ )
769 if( in(i) == nullptr ) // Find the null at end of prec edge list
770 break; // There must be one, since we grew the array
771 _in[i] = in(_cnt); // Move prec over, making space for req edge
772 }
773 _in[_cnt++] = n; // Stuff over old prec edge
774 if (n != nullptr) n->add_out((Node *)this);
775 Compile::current()->record_modified_node(this);
776 }
777
778 //---------------------------add_req_batch-------------------------------------
779 // Add a new required input at the end
780 void Node::add_req_batch( Node *n, uint m ) {
781 assert( is_not_dead(n), "can not use dead node");
782 // check various edge cases
783 if ((int)m <= 1) {
784 assert((int)m >= 0, "oob");
785 if (m != 0) add_req(n);
786 return;
787 }
788
789 // Look to see if I can move precedence down one without reallocating
790 if( (_cnt+m) > _max || _in[_max-m] )
791 grow( _max+m );
792
793 // Find a precedence edge to move
794 if( _in[_cnt] != nullptr ) { // Next precedence edge is busy?
795 uint i;
796 for( i=_cnt; i<_max; i++ )
797 if( _in[i] == nullptr ) // Find the null at end of prec edge list
798 break; // There must be one, since we grew the array
799 // Slide all the precs over by m positions (assume #prec << m).
800 Copy::conjoint_words_to_higher((HeapWord*)&_in[_cnt], (HeapWord*)&_in[_cnt+m], ((i-_cnt)*sizeof(Node*)));
801 }
802
803 // Stuff over the old prec edges
804 for(uint i=0; i<m; i++ ) {
805 _in[_cnt++] = n;
806 }
807
808 // Insert multiple out edges on the node.
809 if (n != nullptr && !n->is_top()) {
810 for(uint i=0; i<m; i++ ) {
811 n->add_out((Node *)this);
812 }
813 }
814 Compile::current()->record_modified_node(this);
815 }
816
817 //------------------------------del_req----------------------------------------
818 // Delete the required edge and compact the edge array
819 void Node::del_req( uint idx ) {
820 assert( idx < _cnt, "oob");
821 assert( !VerifyHashTableKeys || _hash_lock == 0,
822 "remove node from hash table before modifying it");
823 // First remove corresponding def-use edge
824 Node *n = in(idx);
825 if (n != nullptr) n->del_out((Node *)this);
826 _in[idx] = in(--_cnt); // Compact the array
827 // Avoid spec violation: Gap in prec edges.
828 close_prec_gap_at(_cnt);
829 Compile::current()->record_modified_node(this);
830 }
831
832 //------------------------------del_req_ordered--------------------------------
833 // Delete the required edge and compact the edge array with preserved order
834 void Node::del_req_ordered( uint idx ) {
835 assert( idx < _cnt, "oob");
836 assert( !VerifyHashTableKeys || _hash_lock == 0,
837 "remove node from hash table before modifying it");
838 // First remove corresponding def-use edge
839 Node *n = in(idx);
840 if (n != nullptr) n->del_out((Node *)this);
841 if (idx < --_cnt) { // Not last edge ?
842 Copy::conjoint_words_to_lower((HeapWord*)&_in[idx+1], (HeapWord*)&_in[idx], ((_cnt-idx)*sizeof(Node*)));
843 }
844 // Avoid spec violation: Gap in prec edges.
845 close_prec_gap_at(_cnt);
846 Compile::current()->record_modified_node(this);
847 }
848
849 //------------------------------ins_req----------------------------------------
850 // Insert a new required input at the end
851 void Node::ins_req( uint idx, Node *n ) {
852 assert( is_not_dead(n), "can not use dead node");
853 add_req(nullptr); // Make space
854 assert( idx < _max, "Must have allocated enough space");
855 // Slide over
856 if(_cnt-idx-1 > 0) {
857 Copy::conjoint_words_to_higher((HeapWord*)&_in[idx], (HeapWord*)&_in[idx+1], ((_cnt-idx-1)*sizeof(Node*)));
858 }
859 _in[idx] = n; // Stuff over old required edge
860 if (n != nullptr) n->add_out((Node *)this); // Add reciprocal def-use edge
861 Compile::current()->record_modified_node(this);
862 }
863
864 //-----------------------------find_edge---------------------------------------
865 int Node::find_edge(Node* n) {
866 for (uint i = 0; i < len(); i++) {
867 if (_in[i] == n) return i;
868 }
869 return -1;
870 }
871
872 //----------------------------replace_edge-------------------------------------
873 int Node::replace_edge(Node* old, Node* neww, PhaseGVN* gvn) {
874 if (old == neww) return 0; // nothing to do
875 uint nrep = 0;
876 for (uint i = 0; i < len(); i++) {
877 if (in(i) == old) {
878 if (i < req()) {
879 if (gvn != nullptr) {
880 set_req_X(i, neww, gvn);
881 } else {
882 set_req(i, neww);
883 }
884 } else {
885 assert(gvn == nullptr || gvn->is_IterGVN() == nullptr, "no support for igvn here");
886 assert(find_prec_edge(neww) == -1, "spec violation: duplicated prec edge (node %d -> %d)", _idx, neww->_idx);
887 set_prec(i, neww);
888 }
889 nrep++;
890 }
891 }
892 return nrep;
893 }
894
895 /**
896 * Replace input edges in the range pointing to 'old' node.
897 */
898 int Node::replace_edges_in_range(Node* old, Node* neww, int start, int end, PhaseGVN* gvn) {
899 if (old == neww) return 0; // nothing to do
900 uint nrep = 0;
901 for (int i = start; i < end; i++) {
902 if (in(i) == old) {
903 set_req_X(i, neww, gvn);
904 nrep++;
905 }
906 }
907 return nrep;
908 }
909
910 //-------------------------disconnect_inputs-----------------------------------
911 // null out all inputs to eliminate incoming Def-Use edges.
912 void Node::disconnect_inputs(Compile* C) {
913 // the layout of Node::_in
914 // r: a required input, null is allowed
915 // p: a precedence, null values are all at the end
916 // -----------------------------------
917 // |r|...|r|p|...|p|null|...|null|
918 // | |
919 // req() len()
920 // -----------------------------------
921 for (uint i = 0; i < req(); ++i) {
922 if (in(i) != nullptr) {
923 set_req(i, nullptr);
924 }
925 }
926
927 // Remove precedence edges if any exist
928 // Note: Safepoints may have precedence edges, even during parsing
929 for (uint i = len(); i > req(); ) {
930 rm_prec(--i); // no-op if _in[i] is null
931 }
932
933 #ifdef ASSERT
934 // sanity check
935 for (uint i = 0; i < len(); ++i) {
936 assert(_in[i] == nullptr, "disconnect_inputs() failed!");
937 }
938 #endif
939
940 // Node::destruct requires all out edges be deleted first
941 // debug_only(destruct();) // no reuse benefit expected
942 C->record_dead_node(_idx);
943 }
944
945 //-----------------------------uncast---------------------------------------
946 // %%% Temporary, until we sort out CheckCastPP vs. CastPP.
947 // Strip away casting. (It is depth-limited.)
948 // Optionally, keep casts with dependencies.
949 Node* Node::uncast(bool keep_deps) const {
950 // Should be inline:
951 //return is_ConstraintCast() ? uncast_helper(this) : (Node*) this;
952 if (is_ConstraintCast()) {
953 return uncast_helper(this, keep_deps);
954 } else {
955 return (Node*) this;
956 }
957 }
958
959 // Find out of current node that matches opcode.
960 Node* Node::find_out_with(int opcode) {
961 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
962 Node* use = fast_out(i);
963 if (use->Opcode() == opcode) {
964 return use;
965 }
966 }
967 return nullptr;
968 }
969
970 // Return true if the current node has an out that matches opcode.
971 bool Node::has_out_with(int opcode) {
972 return (find_out_with(opcode) != nullptr);
973 }
974
975 // Return true if the current node has an out that matches any of the opcodes.
976 bool Node::has_out_with(int opcode1, int opcode2, int opcode3, int opcode4) {
977 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
978 int opcode = fast_out(i)->Opcode();
979 if (opcode == opcode1 || opcode == opcode2 || opcode == opcode3 || opcode == opcode4) {
980 return true;
981 }
982 }
983 return false;
984 }
985
986
987 //---------------------------uncast_helper-------------------------------------
988 Node* Node::uncast_helper(const Node* p, bool keep_deps) {
989 #ifdef ASSERT
990 uint depth_count = 0;
991 const Node* orig_p = p;
992 #endif
993
994 while (true) {
995 #ifdef ASSERT
996 if (depth_count >= K) {
997 orig_p->dump(4);
998 if (p != orig_p)
999 p->dump(1);
1000 }
1001 assert(depth_count++ < K, "infinite loop in Node::uncast_helper");
1002 #endif
1003 if (p == nullptr || p->req() != 2) {
1004 break;
1005 } else if (p->is_ConstraintCast()) {
1006 if (keep_deps && p->as_ConstraintCast()->carry_dependency()) {
1007 break; // stop at casts with dependencies
1008 }
1009 p = p->in(1);
1010 } else {
1011 break;
1012 }
1013 }
1014 return (Node*) p;
1015 }
1016
1017 //------------------------------add_prec---------------------------------------
1018 // Add a new precedence input. Precedence inputs are unordered, with
1019 // duplicates removed and nulls packed down at the end.
1020 void Node::add_prec( Node *n ) {
1021 assert( is_not_dead(n), "can not use dead node");
1022
1023 // Check for null at end
1024 if( _cnt >= _max || in(_max-1) )
1025 grow( _max+1 );
1026
1027 // Find a precedence edge to move
1028 uint i = _cnt;
1029 while( in(i) != nullptr ) {
1030 if (in(i) == n) return; // Avoid spec violation: duplicated prec edge.
1031 i++;
1032 }
1033 _in[i] = n; // Stuff prec edge over null
1034 if ( n != nullptr) n->add_out((Node *)this); // Add mirror edge
1035
1036 #ifdef ASSERT
1037 while ((++i)<_max) { assert(_in[i] == nullptr, "spec violation: Gap in prec edges (node %d)", _idx); }
1038 #endif
1039 Compile::current()->record_modified_node(this);
1040 }
1041
1042 //------------------------------rm_prec----------------------------------------
1043 // Remove a precedence input. Precedence inputs are unordered, with
1044 // duplicates removed and nulls packed down at the end.
1045 void Node::rm_prec( uint j ) {
1046 assert(j < _max, "oob: i=%d, _max=%d", j, _max);
1047 assert(j >= _cnt, "not a precedence edge");
1048 if (_in[j] == nullptr) return; // Avoid spec violation: Gap in prec edges.
1049 _in[j]->del_out((Node *)this);
1050 close_prec_gap_at(j);
1051 Compile::current()->record_modified_node(this);
1052 }
1053
1054 //------------------------------size_of----------------------------------------
1055 uint Node::size_of() const { return sizeof(*this); }
1056
1057 //------------------------------ideal_reg--------------------------------------
1058 uint Node::ideal_reg() const { return 0; }
1059
1060 //------------------------------jvms-------------------------------------------
1061 JVMState* Node::jvms() const { return nullptr; }
1062
1063 #ifdef ASSERT
1064 //------------------------------jvms-------------------------------------------
1065 bool Node::verify_jvms(const JVMState* using_jvms) const {
1066 for (JVMState* jvms = this->jvms(); jvms != nullptr; jvms = jvms->caller()) {
1067 if (jvms == using_jvms) return true;
1068 }
1069 return false;
1070 }
1071
1072 //------------------------------init_NodeProperty------------------------------
1073 void Node::init_NodeProperty() {
1074 assert(_max_classes <= max_juint, "too many NodeProperty classes");
1075 assert(max_flags() <= max_juint, "too many NodeProperty flags");
1076 }
1077
1078 //-----------------------------max_flags---------------------------------------
1079 juint Node::max_flags() {
1080 return (PD::_last_flag << 1) - 1; // allow flags combination
1081 }
1082 #endif
1083
1084 //------------------------------format-----------------------------------------
1085 // Print as assembly
1086 void Node::format( PhaseRegAlloc *, outputStream *st ) const {}
1087 //------------------------------emit-------------------------------------------
1088 // Emit bytes starting at parameter 'ptr'.
1089 void Node::emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const {}
1090 //------------------------------size-------------------------------------------
1091 // Size of instruction in bytes
1092 uint Node::size(PhaseRegAlloc *ra_) const { return 0; }
1093
1094 //------------------------------CFG Construction-------------------------------
1095 // Nodes that end basic blocks, e.g. IfTrue/IfFalse, JumpProjNode, Root,
1096 // Goto and Return.
1097 const Node *Node::is_block_proj() const { return 0; }
1098
1099 // Minimum guaranteed type
1100 const Type *Node::bottom_type() const { return Type::BOTTOM; }
1101
1102
1103 //------------------------------raise_bottom_type------------------------------
1104 // Get the worst-case Type output for this Node.
1105 void Node::raise_bottom_type(const Type* new_type) {
1106 if (is_Type()) {
1107 TypeNode *n = this->as_Type();
1108 if (VerifyAliases) {
1109 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1110 }
1111 n->set_type(new_type);
1112 } else if (is_Load()) {
1113 LoadNode *n = this->as_Load();
1114 if (VerifyAliases) {
1115 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1116 }
1117 n->set_type(new_type);
1118 }
1119 }
1120
1121 //------------------------------Identity---------------------------------------
1122 // Return a node that the given node is equivalent to.
1123 Node* Node::Identity(PhaseGVN* phase) {
1124 return this; // Default to no identities
1125 }
1126
1127 //------------------------------Value------------------------------------------
1128 // Compute a new Type for a node using the Type of the inputs.
1129 const Type* Node::Value(PhaseGVN* phase) const {
1130 return bottom_type(); // Default to worst-case Type
1131 }
1132
1133 //------------------------------Ideal------------------------------------------
1134 //
1135 // 'Idealize' the graph rooted at this Node.
1136 //
1137 // In order to be efficient and flexible there are some subtle invariants
1138 // these Ideal calls need to hold. Running with '-XX:VerifyIterativeGVN=1' checks
1139 // these invariants, although its too slow to have on by default. If you are
1140 // hacking an Ideal call, be sure to test with '-XX:VerifyIterativeGVN=1'
1141 //
1142 // The Ideal call almost arbitrarily reshape the graph rooted at the 'this'
1143 // pointer. If ANY change is made, it must return the root of the reshaped
1144 // graph - even if the root is the same Node. Example: swapping the inputs
1145 // to an AddINode gives the same answer and same root, but you still have to
1146 // return the 'this' pointer instead of null.
1147 //
1148 // You cannot return an OLD Node, except for the 'this' pointer. Use the
1149 // Identity call to return an old Node; basically if Identity can find
1150 // another Node have the Ideal call make no change and return null.
1151 // Example: AddINode::Ideal must check for add of zero; in this case it
1152 // returns null instead of doing any graph reshaping.
1153 //
1154 // You cannot modify any old Nodes except for the 'this' pointer. Due to
1155 // sharing there may be other users of the old Nodes relying on their current
1156 // semantics. Modifying them will break the other users.
1157 // Example: when reshape "(X+3)+4" into "X+7" you must leave the Node for
1158 // "X+3" unchanged in case it is shared.
1159 //
1160 // If you modify the 'this' pointer's inputs, you should use
1161 // 'set_req'. If you are making a new Node (either as the new root or
1162 // some new internal piece) you may use 'init_req' to set the initial
1163 // value. You can make a new Node with either 'new' or 'clone'. In
1164 // either case, def-use info is correctly maintained.
1165 //
1166 // Example: reshape "(X+3)+4" into "X+7":
1167 // set_req(1, in(1)->in(1));
1168 // set_req(2, phase->intcon(7));
1169 // return this;
1170 // Example: reshape "X*4" into "X<<2"
1171 // return new LShiftINode(in(1), phase->intcon(2));
1172 //
1173 // You must call 'phase->transform(X)' on any new Nodes X you make, except
1174 // for the returned root node. Example: reshape "X*31" with "(X<<5)-X".
1175 // Node *shift=phase->transform(new LShiftINode(in(1),phase->intcon(5)));
1176 // return new AddINode(shift, in(1));
1177 //
1178 // When making a Node for a constant use 'phase->makecon' or 'phase->intcon'.
1179 // These forms are faster than 'phase->transform(new ConNode())' and Do
1180 // The Right Thing with def-use info.
1181 //
1182 // You cannot bury the 'this' Node inside of a graph reshape. If the reshaped
1183 // graph uses the 'this' Node it must be the root. If you want a Node with
1184 // the same Opcode as the 'this' pointer use 'clone'.
1185 //
1186 Node *Node::Ideal(PhaseGVN *phase, bool can_reshape) {
1187 return nullptr; // Default to being Ideal already
1188 }
1189
1190 // Some nodes have specific Ideal subgraph transformations only if they are
1191 // unique users of specific nodes. Such nodes should be put on IGVN worklist
1192 // for the transformations to happen.
1193 bool Node::has_special_unique_user() const {
1194 assert(outcnt() == 1, "match only for unique out");
1195 Node* n = unique_out();
1196 int op = Opcode();
1197 if (this->is_Store()) {
1198 // Condition for back-to-back stores folding.
1199 return n->Opcode() == op && n->in(MemNode::Memory) == this;
1200 } else if (this->is_Load() || this->is_DecodeN() || this->is_Phi()) {
1201 // Condition for removing an unused LoadNode or DecodeNNode from the MemBarAcquire precedence input
1202 return n->Opcode() == Op_MemBarAcquire;
1203 } else if (op == Op_AddL) {
1204 // Condition for convL2I(addL(x,y)) ==> addI(convL2I(x),convL2I(y))
1205 return n->Opcode() == Op_ConvL2I && n->in(1) == this;
1206 } else if (op == Op_SubI || op == Op_SubL) {
1207 // Condition for subI(x,subI(y,z)) ==> subI(addI(x,z),y)
1208 return n->Opcode() == op && n->in(2) == this;
1209 } else if (is_If() && (n->is_IfFalse() || n->is_IfTrue())) {
1210 // See IfProjNode::Identity()
1211 return true;
1212 } else if ((is_IfFalse() || is_IfTrue()) && n->is_If()) {
1213 // See IfNode::fold_compares
1214 return true;
1215 } else {
1216 return false;
1217 }
1218 };
1219
1220 //--------------------------find_exact_control---------------------------------
1221 // Skip Proj and CatchProj nodes chains. Check for Null and Top.
1222 Node* Node::find_exact_control(Node* ctrl) {
1223 if (ctrl == nullptr && this->is_Region())
1224 ctrl = this->as_Region()->is_copy();
1225
1226 if (ctrl != nullptr && ctrl->is_CatchProj()) {
1227 if (ctrl->as_CatchProj()->_con == CatchProjNode::fall_through_index)
1228 ctrl = ctrl->in(0);
1229 if (ctrl != nullptr && !ctrl->is_top())
1230 ctrl = ctrl->in(0);
1231 }
1232
1233 if (ctrl != nullptr && ctrl->is_Proj())
1234 ctrl = ctrl->in(0);
1235
1236 return ctrl;
1237 }
1238
1239 //--------------------------dominates------------------------------------------
1240 // Helper function for MemNode::all_controls_dominate().
1241 // Check if 'this' control node dominates or equal to 'sub' control node.
1242 // We already know that if any path back to Root or Start reaches 'this',
1243 // then all paths so, so this is a simple search for one example,
1244 // not an exhaustive search for a counterexample.
1245 bool Node::dominates(Node* sub, Node_List &nlist) {
1246 assert(this->is_CFG(), "expecting control");
1247 assert(sub != nullptr && sub->is_CFG(), "expecting control");
1248
1249 // detect dead cycle without regions
1250 int iterations_without_region_limit = DominatorSearchLimit;
1251
1252 Node* orig_sub = sub;
1253 Node* dom = this;
1254 bool met_dom = false;
1255 nlist.clear();
1256
1257 // Walk 'sub' backward up the chain to 'dom', watching for regions.
1258 // After seeing 'dom', continue up to Root or Start.
1259 // If we hit a region (backward split point), it may be a loop head.
1260 // Keep going through one of the region's inputs. If we reach the
1261 // same region again, go through a different input. Eventually we
1262 // will either exit through the loop head, or give up.
1263 // (If we get confused, break out and return a conservative 'false'.)
1264 while (sub != nullptr) {
1265 if (sub->is_top()) break; // Conservative answer for dead code.
1266 if (sub == dom) {
1267 if (nlist.size() == 0) {
1268 // No Region nodes except loops were visited before and the EntryControl
1269 // path was taken for loops: it did not walk in a cycle.
1270 return true;
1271 } else if (met_dom) {
1272 break; // already met before: walk in a cycle
1273 } else {
1274 // Region nodes were visited. Continue walk up to Start or Root
1275 // to make sure that it did not walk in a cycle.
1276 met_dom = true; // first time meet
1277 iterations_without_region_limit = DominatorSearchLimit; // Reset
1278 }
1279 }
1280 if (sub->is_Start() || sub->is_Root()) {
1281 // Success if we met 'dom' along a path to Start or Root.
1282 // We assume there are no alternative paths that avoid 'dom'.
1283 // (This assumption is up to the caller to ensure!)
1284 return met_dom;
1285 }
1286 Node* up = sub->in(0);
1287 // Normalize simple pass-through regions and projections:
1288 up = sub->find_exact_control(up);
1289 // If sub == up, we found a self-loop. Try to push past it.
1290 if (sub == up && sub->is_Loop()) {
1291 // Take loop entry path on the way up to 'dom'.
1292 up = sub->in(1); // in(LoopNode::EntryControl);
1293 } else if (sub == up && sub->is_Region() && sub->req() == 2) {
1294 // Take in(1) path on the way up to 'dom' for regions with only one input
1295 up = sub->in(1);
1296 } else if (sub == up && sub->is_Region()) {
1297 // Try both paths for Regions with 2 input paths (it may be a loop head).
1298 // It could give conservative 'false' answer without information
1299 // which region's input is the entry path.
1300 iterations_without_region_limit = DominatorSearchLimit; // Reset
1301
1302 bool region_was_visited_before = false;
1303 // Was this Region node visited before?
1304 // If so, we have reached it because we accidentally took a
1305 // loop-back edge from 'sub' back into the body of the loop,
1306 // and worked our way up again to the loop header 'sub'.
1307 // So, take the first unexplored path on the way up to 'dom'.
1308 for (int j = nlist.size() - 1; j >= 0; j--) {
1309 intptr_t ni = (intptr_t)nlist.at(j);
1310 Node* visited = (Node*)(ni & ~1);
1311 bool visited_twice_already = ((ni & 1) != 0);
1312 if (visited == sub) {
1313 if (visited_twice_already) {
1314 // Visited 2 paths, but still stuck in loop body. Give up.
1315 return false;
1316 }
1317 // The Region node was visited before only once.
1318 // (We will repush with the low bit set, below.)
1319 nlist.remove(j);
1320 // We will find a new edge and re-insert.
1321 region_was_visited_before = true;
1322 break;
1323 }
1324 }
1325
1326 // Find an incoming edge which has not been seen yet; walk through it.
1327 assert(up == sub, "");
1328 uint skip = region_was_visited_before ? 1 : 0;
1329 for (uint i = 1; i < sub->req(); i++) {
1330 Node* in = sub->in(i);
1331 if (in != nullptr && !in->is_top() && in != sub) {
1332 if (skip == 0) {
1333 up = in;
1334 break;
1335 }
1336 --skip; // skip this nontrivial input
1337 }
1338 }
1339
1340 // Set 0 bit to indicate that both paths were taken.
1341 nlist.push((Node*)((intptr_t)sub + (region_was_visited_before ? 1 : 0)));
1342 }
1343
1344 if (up == sub) {
1345 break; // some kind of tight cycle
1346 }
1347 if (up == orig_sub && met_dom) {
1348 // returned back after visiting 'dom'
1349 break; // some kind of cycle
1350 }
1351 if (--iterations_without_region_limit < 0) {
1352 break; // dead cycle
1353 }
1354 sub = up;
1355 }
1356
1357 // Did not meet Root or Start node in pred. chain.
1358 // Conservative answer for dead code.
1359 return false;
1360 }
1361
1362 //------------------------------remove_dead_region-----------------------------
1363 // This control node is dead. Follow the subgraph below it making everything
1364 // using it dead as well. This will happen normally via the usual IterGVN
1365 // worklist but this call is more efficient. Do not update use-def info
1366 // inside the dead region, just at the borders.
1367 static void kill_dead_code( Node *dead, PhaseIterGVN *igvn ) {
1368 // Con's are a popular node to re-hit in the hash table again.
1369 if( dead->is_Con() ) return;
1370
1371 ResourceMark rm;
1372 Node_List nstack;
1373 VectorSet dead_set; // notify uses only once
1374
1375 Node *top = igvn->C->top();
1376 nstack.push(dead);
1377 bool has_irreducible_loop = igvn->C->has_irreducible_loop();
1378
1379 while (nstack.size() > 0) {
1380 dead = nstack.pop();
1381 if (!dead_set.test_set(dead->_idx)) {
1382 // If dead has any live uses, those are now still attached. Notify them before we lose them.
1383 igvn->add_users_to_worklist(dead);
1384 }
1385 if (dead->Opcode() == Op_SafePoint) {
1386 dead->as_SafePoint()->disconnect_from_root(igvn);
1387 }
1388 if (dead->outcnt() > 0) {
1389 // Keep dead node on stack until all uses are processed.
1390 nstack.push(dead);
1391 // For all Users of the Dead... ;-)
1392 for (DUIterator_Last kmin, k = dead->last_outs(kmin); k >= kmin; ) {
1393 Node* use = dead->last_out(k);
1394 igvn->hash_delete(use); // Yank from hash table prior to mod
1395 if (use->in(0) == dead) { // Found another dead node
1396 assert (!use->is_Con(), "Control for Con node should be Root node.");
1397 use->set_req(0, top); // Cut dead edge to prevent processing
1398 nstack.push(use); // the dead node again.
1399 } else if (!has_irreducible_loop && // Backedge could be alive in irreducible loop
1400 use->is_Loop() && !use->is_Root() && // Don't kill Root (RootNode extends LoopNode)
1401 use->in(LoopNode::EntryControl) == dead) { // Dead loop if its entry is dead
1402 use->set_req(LoopNode::EntryControl, top); // Cut dead edge to prevent processing
1403 use->set_req(0, top); // Cut self edge
1404 nstack.push(use);
1405 } else { // Else found a not-dead user
1406 // Dead if all inputs are top or null
1407 bool dead_use = !use->is_Root(); // Keep empty graph alive
1408 for (uint j = 1; j < use->req(); j++) {
1409 Node* in = use->in(j);
1410 if (in == dead) { // Turn all dead inputs into TOP
1411 use->set_req(j, top);
1412 } else if (in != nullptr && !in->is_top()) {
1413 dead_use = false;
1414 }
1415 }
1416 if (dead_use) {
1417 if (use->is_Region()) {
1418 use->set_req(0, top); // Cut self edge
1419 }
1420 nstack.push(use);
1421 } else {
1422 igvn->_worklist.push(use);
1423 }
1424 }
1425 // Refresh the iterator, since any number of kills might have happened.
1426 k = dead->last_outs(kmin);
1427 }
1428 } else { // (dead->outcnt() == 0)
1429 // Done with outputs.
1430 igvn->hash_delete(dead);
1431 igvn->_worklist.remove(dead);
1432 igvn->set_type(dead, Type::TOP);
1433 // Kill all inputs to the dead guy
1434 for (uint i=0; i < dead->req(); i++) {
1435 Node *n = dead->in(i); // Get input to dead guy
1436 if (n != nullptr && !n->is_top()) { // Input is valid?
1437 dead->set_req(i, top); // Smash input away
1438 if (n->outcnt() == 0) { // Input also goes dead?
1439 if (!n->is_Con())
1440 nstack.push(n); // Clear it out as well
1441 } else if (n->outcnt() == 1 &&
1442 n->has_special_unique_user()) {
1443 igvn->add_users_to_worklist( n );
1444 } else if (n->outcnt() <= 2 && n->is_Store()) {
1445 // Push store's uses on worklist to enable folding optimization for
1446 // store/store and store/load to the same address.
1447 // The restriction (outcnt() <= 2) is the same as in set_req_X()
1448 // and remove_globally_dead_node().
1449 igvn->add_users_to_worklist( n );
1450 } else {
1451 BarrierSet::barrier_set()->barrier_set_c2()->enqueue_useful_gc_barrier(igvn, n);
1452 }
1453 }
1454 }
1455 igvn->C->remove_useless_node(dead);
1456 } // (dead->outcnt() == 0)
1457 } // while (nstack.size() > 0) for outputs
1458 return;
1459 }
1460
1461 //------------------------------remove_dead_region-----------------------------
1462 bool Node::remove_dead_region(PhaseGVN *phase, bool can_reshape) {
1463 Node *n = in(0);
1464 if( !n ) return false;
1465 // Lost control into this guy? I.e., it became unreachable?
1466 // Aggressively kill all unreachable code.
1467 if (can_reshape && n->is_top()) {
1468 kill_dead_code(this, phase->is_IterGVN());
1469 return false; // Node is dead.
1470 }
1471
1472 if( n->is_Region() && n->as_Region()->is_copy() ) {
1473 Node *m = n->nonnull_req();
1474 set_req(0, m);
1475 return true;
1476 }
1477 return false;
1478 }
1479
1480 //------------------------------hash-------------------------------------------
1481 // Hash function over Nodes.
1482 uint Node::hash() const {
1483 uint sum = 0;
1484 for( uint i=0; i<_cnt; i++ ) // Add in all inputs
1485 sum = (sum<<1)-(uintptr_t)in(i); // Ignore embedded nulls
1486 return (sum>>2) + _cnt + Opcode();
1487 }
1488
1489 //------------------------------cmp--------------------------------------------
1490 // Compare special parts of simple Nodes
1491 bool Node::cmp( const Node &n ) const {
1492 return true; // Must be same
1493 }
1494
1495 //------------------------------rematerialize-----------------------------------
1496 // Should we clone rather than spill this instruction?
1497 bool Node::rematerialize() const {
1498 if ( is_Mach() )
1499 return this->as_Mach()->rematerialize();
1500 else
1501 return (_flags & Flag_rematerialize) != 0;
1502 }
1503
1504 //------------------------------needs_anti_dependence_check---------------------
1505 // Nodes which use memory without consuming it, hence need antidependences.
1506 bool Node::needs_anti_dependence_check() const {
1507 if (req() < 2 || (_flags & Flag_needs_anti_dependence_check) == 0) {
1508 return false;
1509 }
1510 return in(1)->bottom_type()->has_memory();
1511 }
1512
1513 // Get an integer constant from a ConNode (or CastIINode).
1514 // Return a default value if there is no apparent constant here.
1515 const TypeInt* Node::find_int_type() const {
1516 if (this->is_Type()) {
1517 return this->as_Type()->type()->isa_int();
1518 } else if (this->is_Con()) {
1519 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1520 return this->bottom_type()->isa_int();
1521 }
1522 return nullptr;
1523 }
1524
1525 const TypeInteger* Node::find_integer_type(BasicType bt) const {
1526 if (this->is_Type()) {
1527 return this->as_Type()->type()->isa_integer(bt);
1528 } else if (this->is_Con()) {
1529 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1530 return this->bottom_type()->isa_integer(bt);
1531 }
1532 return nullptr;
1533 }
1534
1535 // Get a pointer constant from a ConstNode.
1536 // Returns the constant if it is a pointer ConstNode
1537 intptr_t Node::get_ptr() const {
1538 assert( Opcode() == Op_ConP, "" );
1539 return ((ConPNode*)this)->type()->is_ptr()->get_con();
1540 }
1541
1542 // Get a narrow oop constant from a ConNNode.
1543 intptr_t Node::get_narrowcon() const {
1544 assert( Opcode() == Op_ConN, "" );
1545 return ((ConNNode*)this)->type()->is_narrowoop()->get_con();
1546 }
1547
1548 // Get a long constant from a ConNode.
1549 // Return a default value if there is no apparent constant here.
1550 const TypeLong* Node::find_long_type() const {
1551 if (this->is_Type()) {
1552 return this->as_Type()->type()->isa_long();
1553 } else if (this->is_Con()) {
1554 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1555 return this->bottom_type()->isa_long();
1556 }
1557 return nullptr;
1558 }
1559
1560
1561 /**
1562 * Return a ptr type for nodes which should have it.
1563 */
1564 const TypePtr* Node::get_ptr_type() const {
1565 const TypePtr* tp = this->bottom_type()->make_ptr();
1566 #ifdef ASSERT
1567 if (tp == nullptr) {
1568 this->dump(1);
1569 assert((tp != nullptr), "unexpected node type");
1570 }
1571 #endif
1572 return tp;
1573 }
1574
1575 // Get a double constant from a ConstNode.
1576 // Returns the constant if it is a double ConstNode
1577 jdouble Node::getd() const {
1578 assert( Opcode() == Op_ConD, "" );
1579 return ((ConDNode*)this)->type()->is_double_constant()->getd();
1580 }
1581
1582 // Get a float constant from a ConstNode.
1583 // Returns the constant if it is a float ConstNode
1584 jfloat Node::getf() const {
1585 assert( Opcode() == Op_ConF, "" );
1586 return ((ConFNode*)this)->type()->is_float_constant()->getf();
1587 }
1588
1589 #ifndef PRODUCT
1590
1591 // Call this from debugger:
1592 Node* old_root() {
1593 Matcher* matcher = Compile::current()->matcher();
1594 if (matcher != nullptr) {
1595 Node* new_root = Compile::current()->root();
1596 Node* old_root = matcher->find_old_node(new_root);
1597 if (old_root != nullptr) {
1598 return old_root;
1599 }
1600 }
1601 tty->print("old_root: not found.\n");
1602 return nullptr;
1603 }
1604
1605 // BFS traverse all reachable nodes from start, call callback on them
1606 template <typename Callback>
1607 void visit_nodes(Node* start, Callback callback, bool traverse_output, bool only_ctrl) {
1608 Unique_Mixed_Node_List worklist;
1609 worklist.add(start);
1610 for (uint i = 0; i < worklist.size(); i++) {
1611 Node* n = worklist[i];
1612 callback(n);
1613 for (uint i = 0; i < n->len(); i++) {
1614 if (!only_ctrl || n->is_Region() || (n->Opcode() == Op_Root) || (i == TypeFunc::Control)) {
1615 // If only_ctrl is set: Add regions, the root node, or control inputs only
1616 worklist.add(n->in(i));
1617 }
1618 }
1619 if (traverse_output && !only_ctrl) {
1620 for (uint i = 0; i < n->outcnt(); i++) {
1621 worklist.add(n->raw_out(i));
1622 }
1623 }
1624 }
1625 }
1626
1627 // BFS traverse from start, return node with idx
1628 Node* find_node_by_idx(Node* start, uint idx, bool traverse_output, bool only_ctrl) {
1629 ResourceMark rm;
1630 Node* result = nullptr;
1631 auto callback = [&] (Node* n) {
1632 if (n->_idx == idx) {
1633 if (result != nullptr) {
1634 tty->print("find_node_by_idx: " INTPTR_FORMAT " and " INTPTR_FORMAT " both have idx==%d\n",
1635 (uintptr_t)result, (uintptr_t)n, idx);
1636 }
1637 result = n;
1638 }
1639 };
1640 visit_nodes(start, callback, traverse_output, only_ctrl);
1641 return result;
1642 }
1643
1644 int node_idx_cmp(const Node** n1, const Node** n2) {
1645 return (*n1)->_idx - (*n2)->_idx;
1646 }
1647
1648 void find_nodes_by_name(Node* start, const char* name) {
1649 ResourceMark rm;
1650 GrowableArray<const Node*> ns;
1651 auto callback = [&] (const Node* n) {
1652 if (StringUtils::is_star_match(name, n->Name())) {
1653 ns.push(n);
1654 }
1655 };
1656 visit_nodes(start, callback, true, false);
1657 ns.sort(node_idx_cmp);
1658 for (int i = 0; i < ns.length(); i++) {
1659 ns.at(i)->dump();
1660 }
1661 }
1662
1663 void find_nodes_by_dump(Node* start, const char* pattern) {
1664 ResourceMark rm;
1665 GrowableArray<const Node*> ns;
1666 auto callback = [&] (const Node* n) {
1667 stringStream stream;
1668 n->dump("", false, &stream);
1669 if (StringUtils::is_star_match(pattern, stream.base())) {
1670 ns.push(n);
1671 }
1672 };
1673 visit_nodes(start, callback, true, false);
1674 ns.sort(node_idx_cmp);
1675 for (int i = 0; i < ns.length(); i++) {
1676 ns.at(i)->dump();
1677 }
1678 }
1679
1680 // call from debugger: find node with name pattern in new/current graph
1681 // name can contain "*" in match pattern to match any characters
1682 // the matching is case insensitive
1683 void find_nodes_by_name(const char* name) {
1684 Node* root = Compile::current()->root();
1685 find_nodes_by_name(root, name);
1686 }
1687
1688 // call from debugger: find node with name pattern in old graph
1689 // name can contain "*" in match pattern to match any characters
1690 // the matching is case insensitive
1691 void find_old_nodes_by_name(const char* name) {
1692 Node* root = old_root();
1693 find_nodes_by_name(root, name);
1694 }
1695
1696 // call from debugger: find node with dump pattern in new/current graph
1697 // can contain "*" in match pattern to match any characters
1698 // the matching is case insensitive
1699 void find_nodes_by_dump(const char* pattern) {
1700 Node* root = Compile::current()->root();
1701 find_nodes_by_dump(root, pattern);
1702 }
1703
1704 // call from debugger: find node with name pattern in old graph
1705 // can contain "*" in match pattern to match any characters
1706 // the matching is case insensitive
1707 void find_old_nodes_by_dump(const char* pattern) {
1708 Node* root = old_root();
1709 find_nodes_by_dump(root, pattern);
1710 }
1711
1712 // Call this from debugger, search in same graph as n:
1713 Node* find_node(Node* n, const int idx) {
1714 return n->find(idx);
1715 }
1716
1717 // Call this from debugger, search in new nodes:
1718 Node* find_node(const int idx) {
1719 return Compile::current()->root()->find(idx);
1720 }
1721
1722 // Call this from debugger, search in old nodes:
1723 Node* find_old_node(const int idx) {
1724 Node* root = old_root();
1725 return (root == nullptr) ? nullptr : root->find(idx);
1726 }
1727
1728 // Call this from debugger, search in same graph as n:
1729 Node* find_ctrl(Node* n, const int idx) {
1730 return n->find_ctrl(idx);
1731 }
1732
1733 // Call this from debugger, search in new nodes:
1734 Node* find_ctrl(const int idx) {
1735 return Compile::current()->root()->find_ctrl(idx);
1736 }
1737
1738 // Call this from debugger, search in old nodes:
1739 Node* find_old_ctrl(const int idx) {
1740 Node* root = old_root();
1741 return (root == nullptr) ? nullptr : root->find_ctrl(idx);
1742 }
1743
1744 //------------------------------find_ctrl--------------------------------------
1745 // Find an ancestor to this node in the control history with given _idx
1746 Node* Node::find_ctrl(int idx) {
1747 return find(idx, true);
1748 }
1749
1750 //------------------------------find-------------------------------------------
1751 // Tries to find the node with the index |idx| starting from this node. If idx is negative,
1752 // the search also includes forward (out) edges. Returns null if not found.
1753 // If only_ctrl is set, the search will only be done on control nodes. Returns null if
1754 // not found or if the node to be found is not a control node (search will not find it).
1755 Node* Node::find(const int idx, bool only_ctrl) {
1756 ResourceMark rm;
1757 return find_node_by_idx(this, abs(idx), (idx < 0), only_ctrl);
1758 }
1759
1760 class PrintBFS {
1761 public:
1762 PrintBFS(const Node* start, const int max_distance, const Node* target, const char* options, outputStream* st)
1763 : _start(start), _max_distance(max_distance), _target(target), _options(options), _output(st),
1764 _dcc(this), _info_uid(cmpkey, hashkey) {}
1765
1766 void run();
1767 private:
1768 // pipeline steps
1769 bool configure();
1770 void collect();
1771 void select();
1772 void select_all();
1773 void select_all_paths();
1774 void select_shortest_path();
1775 void sort();
1776 void print();
1777
1778 // inputs
1779 const Node* _start;
1780 const int _max_distance;
1781 const Node* _target;
1782 const char* _options;
1783 outputStream* _output;
1784
1785 // options
1786 bool _traverse_inputs = false;
1787 bool _traverse_outputs = false;
1788 struct Filter {
1789 bool _control = false;
1790 bool _memory = false;
1791 bool _data = false;
1792 bool _mixed = false;
1793 bool _other = false;
1794 bool is_empty() const {
1795 return !(_control || _memory || _data || _mixed || _other);
1796 }
1797 void set_all() {
1798 _control = true;
1799 _memory = true;
1800 _data = true;
1801 _mixed = true;
1802 _other = true;
1803 }
1804 // Check if the filter accepts the node. Go by the type categories, but also all CFG nodes
1805 // are considered to have control.
1806 bool accepts(const Node* n) {
1807 const Type* t = n->bottom_type();
1808 return ( _data && t->has_category(Type::Category::Data) ) ||
1809 ( _memory && t->has_category(Type::Category::Memory) ) ||
1810 ( _mixed && t->has_category(Type::Category::Mixed) ) ||
1811 ( _control && (t->has_category(Type::Category::Control) || n->is_CFG()) ) ||
1812 ( _other && t->has_category(Type::Category::Other) );
1813 }
1814 };
1815 Filter _filter_visit;
1816 Filter _filter_boundary;
1817 bool _sort_idx = false;
1818 bool _all_paths = false;
1819 bool _use_color = false;
1820 bool _print_blocks = false;
1821 bool _print_old = false;
1822 bool _dump_only = false;
1823 void print_options_help(bool print_examples);
1824 bool parse_options();
1825
1826 public:
1827 class DumpConfigColored : public Node::DumpConfig {
1828 public:
1829 DumpConfigColored(PrintBFS* bfs) : _bfs(bfs) {};
1830 virtual void pre_dump(outputStream* st, const Node* n);
1831 virtual void post_dump(outputStream* st);
1832 private:
1833 PrintBFS* _bfs;
1834 };
1835 private:
1836 DumpConfigColored _dcc;
1837
1838 // node info
1839 static Node* old_node(const Node* n); // mach node -> prior IR node
1840 void print_node_idx(const Node* n);
1841 void print_block_id(const Block* b);
1842 void print_node_block(const Node* n); // _pre_order, head idx, _idom, _dom_depth
1843
1844 // traversal data structures
1845 GrowableArray<const Node*> _worklist; // BFS queue
1846 void maybe_traverse(const Node* src, const Node* dst);
1847
1848 // node info annotation
1849 class Info {
1850 public:
1851 Info() : Info(nullptr, 0) {};
1852 Info(const Node* node, int distance)
1853 : _node(node), _distance_from_start(distance) {};
1854 const Node* node() const { return _node; };
1855 int distance() const { return _distance_from_start; };
1856 int distance_from_target() const { return _distance_from_target; }
1857 void set_distance_from_target(int d) { _distance_from_target = d; }
1858 GrowableArray<const Node*> edge_bwd; // pointing toward _start
1859 bool is_marked() const { return _mark; } // marked to keep during select
1860 void set_mark() { _mark = true; }
1861 private:
1862 const Node* _node;
1863 int _distance_from_start; // distance from _start
1864 int _distance_from_target = 0; // distance from _target if _all_paths
1865 bool _mark = false;
1866 };
1867 Dict _info_uid; // Node -> uid
1868 GrowableArray<Info> _info; // uid -> info
1869
1870 Info* find_info(const Node* n) {
1871 size_t uid = (size_t)_info_uid[n];
1872 if (uid == 0) {
1873 return nullptr;
1874 }
1875 return &_info.at((int)uid);
1876 }
1877
1878 void make_info(const Node* node, const int distance) {
1879 assert(find_info(node) == nullptr, "node does not yet have info");
1880 size_t uid = _info.length() + 1;
1881 _info_uid.Insert((void*)node, (void*)uid);
1882 _info.at_put_grow((int)uid, Info(node, distance));
1883 assert(find_info(node)->node() == node, "stored correct node");
1884 };
1885
1886 // filled by sort, printed by print
1887 GrowableArray<const Node*> _print_list;
1888
1889 // print header + node table
1890 void print_header() const;
1891 void print_node(const Node* n);
1892 };
1893
1894 void PrintBFS::run() {
1895 if (!configure()) {
1896 return;
1897 }
1898 collect();
1899 select();
1900 sort();
1901 print();
1902 }
1903
1904 // set up configuration for BFS and print
1905 bool PrintBFS::configure() {
1906 if (_max_distance < 0) {
1907 _output->print_cr("dump_bfs: max_distance must be non-negative!");
1908 return false;
1909 }
1910 return parse_options();
1911 }
1912
1913 // BFS traverse according to configuration, fill worklist and info
1914 void PrintBFS::collect() {
1915 maybe_traverse(_start, _start);
1916 int pos = 0;
1917 while (pos < _worklist.length()) {
1918 const Node* n = _worklist.at(pos++); // next node to traverse
1919 Info* info = find_info(n);
1920 if (!_filter_visit.accepts(n) && n != _start) {
1921 continue; // we hit boundary, do not traverse further
1922 }
1923 if (n != _start && n->is_Root()) {
1924 continue; // traversing through root node would lead to unrelated nodes
1925 }
1926 if (_traverse_inputs && _max_distance > info->distance()) {
1927 for (uint i = 0; i < n->req(); i++) {
1928 maybe_traverse(n, n->in(i));
1929 }
1930 }
1931 if (_traverse_outputs && _max_distance > info->distance()) {
1932 for (uint i = 0; i < n->outcnt(); i++) {
1933 maybe_traverse(n, n->raw_out(i));
1934 }
1935 }
1936 }
1937 }
1938
1939 // go through work list, mark those that we want to print
1940 void PrintBFS::select() {
1941 if (_target == nullptr ) {
1942 select_all();
1943 } else {
1944 if (find_info(_target) == nullptr) {
1945 _output->print_cr("Could not find target in BFS.");
1946 return;
1947 }
1948 if (_all_paths) {
1949 select_all_paths();
1950 } else {
1951 select_shortest_path();
1952 }
1953 }
1954 }
1955
1956 // take all nodes from BFS
1957 void PrintBFS::select_all() {
1958 for (int i = 0; i < _worklist.length(); i++) {
1959 const Node* n = _worklist.at(i);
1960 Info* info = find_info(n);
1961 info->set_mark();
1962 }
1963 }
1964
1965 // traverse backward from target, along edges found in BFS
1966 void PrintBFS::select_all_paths() {
1967 int pos = 0;
1968 GrowableArray<const Node*> backtrace;
1969 // start from target
1970 backtrace.push(_target);
1971 find_info(_target)->set_mark();
1972 // traverse backward
1973 while (pos < backtrace.length()) {
1974 const Node* n = backtrace.at(pos++);
1975 Info* info = find_info(n);
1976 for (int i = 0; i < info->edge_bwd.length(); i++) {
1977 // all backward edges
1978 const Node* back = info->edge_bwd.at(i);
1979 Info* back_info = find_info(back);
1980 if (!back_info->is_marked()) {
1981 // not yet found this on way back.
1982 back_info->set_distance_from_target(info->distance_from_target() + 1);
1983 if (back_info->distance_from_target() + back_info->distance() <= _max_distance) {
1984 // total distance is small enough
1985 back_info->set_mark();
1986 backtrace.push(back);
1987 }
1988 }
1989 }
1990 }
1991 }
1992
1993 void PrintBFS::select_shortest_path() {
1994 const Node* current = _target;
1995 while (true) {
1996 Info* info = find_info(current);
1997 info->set_mark();
1998 if (current == _start) {
1999 break;
2000 }
2001 // first edge -> leads us one step closer to _start
2002 current = info->edge_bwd.at(0);
2003 }
2004 }
2005
2006 // go through worklist in desired order, put the marked ones in print list
2007 void PrintBFS::sort() {
2008 if (_traverse_inputs && !_traverse_outputs) {
2009 // reverse order
2010 for (int i = _worklist.length() - 1; i >= 0; i--) {
2011 const Node* n = _worklist.at(i);
2012 Info* info = find_info(n);
2013 if (info->is_marked()) {
2014 _print_list.push(n);
2015 }
2016 }
2017 } else {
2018 // same order as worklist
2019 for (int i = 0; i < _worklist.length(); i++) {
2020 const Node* n = _worklist.at(i);
2021 Info* info = find_info(n);
2022 if (info->is_marked()) {
2023 _print_list.push(n);
2024 }
2025 }
2026 }
2027 if (_sort_idx) {
2028 _print_list.sort(node_idx_cmp);
2029 }
2030 }
2031
2032 // go through printlist and print
2033 void PrintBFS::print() {
2034 if (_print_list.length() > 0 ) {
2035 print_header();
2036 for (int i = 0; i < _print_list.length(); i++) {
2037 const Node* n = _print_list.at(i);
2038 print_node(n);
2039 }
2040 } else {
2041 _output->print_cr("No nodes to print.");
2042 }
2043 }
2044
2045 void PrintBFS::print_options_help(bool print_examples) {
2046 _output->print_cr("Usage: node->dump_bfs(int max_distance, Node* target, char* options)");
2047 _output->print_cr("");
2048 _output->print_cr("Use cases:");
2049 _output->print_cr(" BFS traversal: no target required");
2050 _output->print_cr(" shortest path: set target");
2051 _output->print_cr(" all paths: set target and put 'A' in options");
2052 _output->print_cr(" detect loop: subcase of all paths, have start==target");
2053 _output->print_cr("");
2054 _output->print_cr("Arguments:");
2055 _output->print_cr(" this/start: staring point of BFS");
2056 _output->print_cr(" target:");
2057 _output->print_cr(" if null: simple BFS");
2058 _output->print_cr(" else: shortest path or all paths between this/start and target");
2059 _output->print_cr(" options:");
2060 _output->print_cr(" if null: same as \"cdmox@B\"");
2061 _output->print_cr(" else: use combination of following characters");
2062 _output->print_cr(" h: display this help info");
2063 _output->print_cr(" H: display this help info, with examples");
2064 _output->print_cr(" +: traverse in-edges (on if neither + nor -)");
2065 _output->print_cr(" -: traverse out-edges");
2066 _output->print_cr(" c: visit control nodes");
2067 _output->print_cr(" d: visit data nodes");
2068 _output->print_cr(" m: visit memory nodes");
2069 _output->print_cr(" o: visit other nodes");
2070 _output->print_cr(" x: visit mixed nodes");
2071 _output->print_cr(" C: boundary control nodes");
2072 _output->print_cr(" D: boundary data nodes");
2073 _output->print_cr(" M: boundary memory nodes");
2074 _output->print_cr(" O: boundary other nodes");
2075 _output->print_cr(" X: boundary mixed nodes");
2076 _output->print_cr(" #: display node category in color (not supported in all terminals)");
2077 _output->print_cr(" S: sort displayed nodes by node idx");
2078 _output->print_cr(" A: all paths (not just shortest path to target)");
2079 _output->print_cr(" @: print old nodes - before matching (if available)");
2080 _output->print_cr(" B: print scheduling blocks (if available)");
2081 _output->print_cr(" $: dump only, no header, no other columns");
2082 _output->print_cr("");
2083 _output->print_cr("recursively follow edges to nodes with permitted visit types,");
2084 _output->print_cr("on the boundary additionally display nodes allowed in boundary types");
2085 _output->print_cr("Note: the categories can be overlapping. For example a mixed node");
2086 _output->print_cr(" can contain control and memory output. Some from the other");
2087 _output->print_cr(" category are also control (Halt, Return, etc).");
2088 _output->print_cr("");
2089 _output->print_cr("output columns:");
2090 _output->print_cr(" dist: BFS distance to this/start");
2091 _output->print_cr(" apd: all paths distance (d_outputart + d_target)");
2092 _output->print_cr(" block: block identifier, based on _pre_order");
2093 _output->print_cr(" head: first node in block");
2094 _output->print_cr(" idom: head node of idom block");
2095 _output->print_cr(" depth: depth of block (_dom_depth)");
2096 _output->print_cr(" old: old IR node - before matching");
2097 _output->print_cr(" dump: node->dump()");
2098 _output->print_cr("");
2099 _output->print_cr("Note: if none of the \"cmdxo\" characters are in the options string");
2100 _output->print_cr(" then we set all of them.");
2101 _output->print_cr(" This allows for short strings like \"#\" for colored input traversal");
2102 _output->print_cr(" or \"-#\" for colored output traversal.");
2103 if (print_examples) {
2104 _output->print_cr("");
2105 _output->print_cr("Examples:");
2106 _output->print_cr(" if->dump_bfs(10, 0, \"+cxo\")");
2107 _output->print_cr(" starting at some if node, traverse inputs recursively");
2108 _output->print_cr(" only along control (mixed and other can also be control)");
2109 _output->print_cr(" phi->dump_bfs(5, 0, \"-dxo\")");
2110 _output->print_cr(" starting at phi node, traverse outputs recursively");
2111 _output->print_cr(" only along data (mixed and other can also have data flow)");
2112 _output->print_cr(" find_node(385)->dump_bfs(3, 0, \"cdmox+#@B\")");
2113 _output->print_cr(" find inputs of node 385, up to 3 nodes up (+)");
2114 _output->print_cr(" traverse all nodes (cdmox), use colors (#)");
2115 _output->print_cr(" display old nodes and blocks, if they exist");
2116 _output->print_cr(" useful call to start with");
2117 _output->print_cr(" find_node(102)->dump_bfs(10, 0, \"dCDMOX-\")");
2118 _output->print_cr(" find non-data dependencies of a data node");
2119 _output->print_cr(" follow data node outputs until we find another category");
2120 _output->print_cr(" node as the boundary");
2121 _output->print_cr(" x->dump_bfs(10, y, 0)");
2122 _output->print_cr(" find shortest path from x to y, along any edge or node");
2123 _output->print_cr(" will not find a path if it is longer than 10");
2124 _output->print_cr(" useful to find how x and y are related");
2125 _output->print_cr(" find_node(741)->dump_bfs(20, find_node(746), \"c+\")");
2126 _output->print_cr(" find shortest control path between two nodes");
2127 _output->print_cr(" find_node(741)->dump_bfs(8, find_node(746), \"cdmox+A\")");
2128 _output->print_cr(" find all paths (A) between two nodes of length at most 8");
2129 _output->print_cr(" find_node(741)->dump_bfs(7, find_node(741), \"c+A\")");
2130 _output->print_cr(" find all control loops for this node");
2131 }
2132 }
2133
2134 bool PrintBFS::parse_options() {
2135 if (_options == nullptr) {
2136 _options = "cdmox@B"; // default options
2137 }
2138 size_t len = strlen(_options);
2139 for (size_t i = 0; i < len; i++) {
2140 switch (_options[i]) {
2141 case '+':
2142 _traverse_inputs = true;
2143 break;
2144 case '-':
2145 _traverse_outputs = true;
2146 break;
2147 case 'c':
2148 _filter_visit._control = true;
2149 break;
2150 case 'm':
2151 _filter_visit._memory = true;
2152 break;
2153 case 'd':
2154 _filter_visit._data = true;
2155 break;
2156 case 'x':
2157 _filter_visit._mixed = true;
2158 break;
2159 case 'o':
2160 _filter_visit._other = true;
2161 break;
2162 case 'C':
2163 _filter_boundary._control = true;
2164 break;
2165 case 'M':
2166 _filter_boundary._memory = true;
2167 break;
2168 case 'D':
2169 _filter_boundary._data = true;
2170 break;
2171 case 'X':
2172 _filter_boundary._mixed = true;
2173 break;
2174 case 'O':
2175 _filter_boundary._other = true;
2176 break;
2177 case 'S':
2178 _sort_idx = true;
2179 break;
2180 case 'A':
2181 _all_paths = true;
2182 break;
2183 case '#':
2184 _use_color = true;
2185 break;
2186 case 'B':
2187 _print_blocks = true;
2188 break;
2189 case '@':
2190 _print_old = true;
2191 break;
2192 case '$':
2193 _dump_only = true;
2194 break;
2195 case 'h':
2196 print_options_help(false);
2197 return false;
2198 case 'H':
2199 print_options_help(true);
2200 return false;
2201 default:
2202 _output->print_cr("dump_bfs: Unrecognized option \'%c\'", _options[i]);
2203 _output->print_cr("for help, run: find_node(0)->dump_bfs(0,0,\"H\")");
2204 return false;
2205 }
2206 }
2207 if (!_traverse_inputs && !_traverse_outputs) {
2208 _traverse_inputs = true;
2209 }
2210 if (_filter_visit.is_empty()) {
2211 _filter_visit.set_all();
2212 }
2213 Compile* C = Compile::current();
2214 _print_old &= (C->matcher() != nullptr); // only show old if there are new
2215 _print_blocks &= (C->cfg() != nullptr); // only show blocks if available
2216 return true;
2217 }
2218
2219 void PrintBFS::DumpConfigColored::pre_dump(outputStream* st, const Node* n) {
2220 if (!_bfs->_use_color) {
2221 return;
2222 }
2223 Info* info = _bfs->find_info(n);
2224 if (info == nullptr || !info->is_marked()) {
2225 return;
2226 }
2227
2228 const Type* t = n->bottom_type();
2229 switch (t->category()) {
2230 case Type::Category::Data:
2231 st->print("\u001b[34m");
2232 break;
2233 case Type::Category::Memory:
2234 st->print("\u001b[32m");
2235 break;
2236 case Type::Category::Mixed:
2237 st->print("\u001b[35m");
2238 break;
2239 case Type::Category::Control:
2240 st->print("\u001b[31m");
2241 break;
2242 case Type::Category::Other:
2243 st->print("\u001b[33m");
2244 break;
2245 case Type::Category::Undef:
2246 n->dump();
2247 assert(false, "category undef ??");
2248 break;
2249 default:
2250 n->dump();
2251 assert(false, "not covered");
2252 break;
2253 }
2254 }
2255
2256 void PrintBFS::DumpConfigColored::post_dump(outputStream* st) {
2257 if (!_bfs->_use_color) {
2258 return;
2259 }
2260 st->print("\u001b[0m"); // white
2261 }
2262
2263 Node* PrintBFS::old_node(const Node* n) {
2264 Compile* C = Compile::current();
2265 if (C->matcher() == nullptr || !C->node_arena()->contains(n)) {
2266 return (Node*)nullptr;
2267 } else {
2268 return C->matcher()->find_old_node(n);
2269 }
2270 }
2271
2272 void PrintBFS::print_node_idx(const Node* n) {
2273 Compile* C = Compile::current();
2274 char buf[30];
2275 if (n == nullptr) {
2276 os::snprintf_checked(buf, sizeof(buf), "_"); // null
2277 } else if (C->node_arena()->contains(n)) {
2278 os::snprintf_checked(buf, sizeof(buf), "%d", n->_idx); // new node
2279 } else {
2280 os::snprintf_checked(buf, sizeof(buf), "o%d", n->_idx); // old node
2281 }
2282 _output->print("%6s", buf);
2283 }
2284
2285 void PrintBFS::print_block_id(const Block* b) {
2286 Compile* C = Compile::current();
2287 char buf[30];
2288 os::snprintf_checked(buf, sizeof(buf), "B%d", b->_pre_order);
2289 _output->print("%7s", buf);
2290 }
2291
2292 void PrintBFS::print_node_block(const Node* n) {
2293 Compile* C = Compile::current();
2294 Block* b = C->node_arena()->contains(n)
2295 ? C->cfg()->get_block_for_node(n)
2296 : nullptr; // guard against old nodes
2297 if (b == nullptr) {
2298 _output->print(" _"); // Block
2299 _output->print(" _"); // head
2300 _output->print(" _"); // idom
2301 _output->print(" _"); // depth
2302 } else {
2303 print_block_id(b);
2304 print_node_idx(b->head());
2305 if (b->_idom) {
2306 print_node_idx(b->_idom->head());
2307 } else {
2308 _output->print(" _"); // idom
2309 }
2310 _output->print("%6d ", b->_dom_depth);
2311 }
2312 }
2313
2314 // filter, and add to worklist, add info, note traversal edges
2315 void PrintBFS::maybe_traverse(const Node* src, const Node* dst) {
2316 if (dst != nullptr &&
2317 (_filter_visit.accepts(dst) ||
2318 _filter_boundary.accepts(dst) ||
2319 dst == _start)) { // correct category or start?
2320 if (find_info(dst) == nullptr) {
2321 // never visited - set up info
2322 _worklist.push(dst);
2323 int d = 0;
2324 if (dst != _start) {
2325 d = find_info(src)->distance() + 1;
2326 }
2327 make_info(dst, d);
2328 }
2329 if (src != dst) {
2330 // traversal edges useful during select
2331 find_info(dst)->edge_bwd.push(src);
2332 }
2333 }
2334 }
2335
2336 void PrintBFS::print_header() const {
2337 if (_dump_only) {
2338 return; // no header in dump only mode
2339 }
2340 _output->print("dist"); // distance
2341 if (_all_paths) {
2342 _output->print(" apd"); // all paths distance
2343 }
2344 if (_print_blocks) {
2345 _output->print(" [block head idom depth]"); // block
2346 }
2347 if (_print_old) {
2348 _output->print(" old"); // old node
2349 }
2350 _output->print(" dump\n"); // node dump
2351 _output->print_cr("---------------------------------------------");
2352 }
2353
2354 void PrintBFS::print_node(const Node* n) {
2355 if (_dump_only) {
2356 n->dump("\n", false, _output, &_dcc);
2357 return;
2358 }
2359 _output->print("%4d", find_info(n)->distance());// distance
2360 if (_all_paths) {
2361 Info* info = find_info(n);
2362 int apd = info->distance() + info->distance_from_target();
2363 _output->print("%4d", apd); // all paths distance
2364 }
2365 if (_print_blocks) {
2366 print_node_block(n); // block
2367 }
2368 if (_print_old) {
2369 print_node_idx(old_node(n)); // old node
2370 }
2371 _output->print(" ");
2372 n->dump("\n", false, _output, &_dcc); // node dump
2373 }
2374
2375 //------------------------------dump_bfs--------------------------------------
2376 // Call this from debugger
2377 // Useful for BFS traversal, shortest path, all path, loop detection, etc
2378 // Designed to be more readable, and provide additional info
2379 // To find all options, run:
2380 // find_node(0)->dump_bfs(0,0,"H")
2381 void Node::dump_bfs(const int max_distance, Node* target, const char* options) const {
2382 dump_bfs(max_distance, target, options, tty);
2383 }
2384
2385 // Used to dump to stream.
2386 void Node::dump_bfs(const int max_distance, Node* target, const char* options, outputStream* st) const {
2387 PrintBFS bfs(this, max_distance, target, options, st);
2388 bfs.run();
2389 }
2390
2391 // Call this from debugger, with default arguments
2392 void Node::dump_bfs(const int max_distance) const {
2393 dump_bfs(max_distance, nullptr, nullptr);
2394 }
2395
2396 // -----------------------------dump_idx---------------------------------------
2397 void Node::dump_idx(bool align, outputStream* st, DumpConfig* dc) const {
2398 if (dc != nullptr) {
2399 dc->pre_dump(st, this);
2400 }
2401 Compile* C = Compile::current();
2402 bool is_new = C->node_arena()->contains(this);
2403 if (align) { // print prefix empty spaces$
2404 // +1 for leading digit, +1 for "o"
2405 uint max_width = static_cast<uint>(log10(static_cast<double>(C->unique()))) + 2;
2406 // +1 for leading digit, maybe +1 for "o"
2407 uint width = static_cast<uint>(log10(static_cast<double>(_idx))) + 1 + (is_new ? 0 : 1);
2408 while (max_width > width) {
2409 st->print(" ");
2410 width++;
2411 }
2412 }
2413 if (!is_new) {
2414 st->print("o");
2415 }
2416 st->print("%d", _idx);
2417 if (dc != nullptr) {
2418 dc->post_dump(st);
2419 }
2420 }
2421
2422 // -----------------------------dump_name--------------------------------------
2423 void Node::dump_name(outputStream* st, DumpConfig* dc) const {
2424 if (dc != nullptr) {
2425 dc->pre_dump(st, this);
2426 }
2427 st->print("%s", Name());
2428 if (dc != nullptr) {
2429 dc->post_dump(st);
2430 }
2431 }
2432
2433 // -----------------------------Name-------------------------------------------
2434 extern const char *NodeClassNames[];
2435 const char *Node::Name() const { return NodeClassNames[Opcode()]; }
2436
2437 static bool is_disconnected(const Node* n) {
2438 for (uint i = 0; i < n->req(); i++) {
2439 if (n->in(i) != nullptr) return false;
2440 }
2441 return true;
2442 }
2443
2444 #ifdef ASSERT
2445 void Node::dump_orig(outputStream *st, bool print_key) const {
2446 Compile* C = Compile::current();
2447 Node* orig = _debug_orig;
2448 if (not_a_node(orig)) orig = nullptr;
2449 if (orig != nullptr && !C->node_arena()->contains(orig)) orig = nullptr;
2450 if (orig == nullptr) return;
2451 if (print_key) {
2452 st->print(" !orig=");
2453 }
2454 Node* fast = orig->debug_orig(); // tortoise & hare algorithm to detect loops
2455 if (not_a_node(fast)) fast = nullptr;
2456 while (orig != nullptr) {
2457 bool discon = is_disconnected(orig); // if discon, print [123] else 123
2458 if (discon) st->print("[");
2459 if (!Compile::current()->node_arena()->contains(orig))
2460 st->print("o");
2461 st->print("%d", orig->_idx);
2462 if (discon) st->print("]");
2463 orig = orig->debug_orig();
2464 if (not_a_node(orig)) orig = nullptr;
2465 if (orig != nullptr && !C->node_arena()->contains(orig)) orig = nullptr;
2466 if (orig != nullptr) st->print(",");
2467 if (fast != nullptr) {
2468 // Step fast twice for each single step of orig:
2469 fast = fast->debug_orig();
2470 if (not_a_node(fast)) fast = nullptr;
2471 if (fast != nullptr && fast != orig) {
2472 fast = fast->debug_orig();
2473 if (not_a_node(fast)) fast = nullptr;
2474 }
2475 if (fast == orig) {
2476 st->print("...");
2477 break;
2478 }
2479 }
2480 }
2481 }
2482
2483 void Node::set_debug_orig(Node* orig) {
2484 _debug_orig = orig;
2485 if (BreakAtNode == 0) return;
2486 if (not_a_node(orig)) orig = nullptr;
2487 int trip = 10;
2488 while (orig != nullptr) {
2489 if (orig->debug_idx() == BreakAtNode || (uintx)orig->_idx == BreakAtNode) {
2490 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=" UINT64_FORMAT " orig._idx=%d orig._debug_idx=" UINT64_FORMAT,
2491 this->_idx, this->debug_idx(), orig->_idx, orig->debug_idx());
2492 BREAKPOINT;
2493 }
2494 orig = orig->debug_orig();
2495 if (not_a_node(orig)) orig = nullptr;
2496 if (trip-- <= 0) break;
2497 }
2498 }
2499 #endif //ASSERT
2500
2501 //------------------------------dump------------------------------------------
2502 // Dump a Node
2503 void Node::dump(const char* suffix, bool mark, outputStream* st, DumpConfig* dc) const {
2504 Compile* C = Compile::current();
2505 bool is_new = C->node_arena()->contains(this);
2506 C->_in_dump_cnt++;
2507
2508 // idx mark name ===
2509 dump_idx(true, st, dc);
2510 st->print(mark ? " >" : " ");
2511 dump_name(st, dc);
2512 st->print(" === ");
2513
2514 // Dump the required and precedence inputs
2515 dump_req(st, dc);
2516 dump_prec(st, dc);
2517 // Dump the outputs
2518 dump_out(st, dc);
2519
2520 if (is_disconnected(this)) {
2521 #ifdef ASSERT
2522 st->print(" [" UINT64_FORMAT "]", debug_idx());
2523 dump_orig(st);
2524 #endif
2525 st->cr();
2526 C->_in_dump_cnt--;
2527 return; // don't process dead nodes
2528 }
2529
2530 if (C->clone_map().value(_idx) != 0) {
2531 C->clone_map().dump(_idx, st);
2532 }
2533 // Dump node-specific info
2534 dump_spec(st);
2535 #ifdef ASSERT
2536 // Dump the non-reset _debug_idx
2537 if (Verbose && WizardMode) {
2538 st->print(" [" UINT64_FORMAT "]", debug_idx());
2539 }
2540 #endif
2541
2542 const Type *t = bottom_type();
2543
2544 if (t != nullptr && (t->isa_instptr() || t->isa_instklassptr())) {
2545 const TypeInstPtr *toop = t->isa_instptr();
2546 const TypeInstKlassPtr *tkls = t->isa_instklassptr();
2547 if (toop) {
2548 st->print(" Oop:");
2549 } else if (tkls) {
2550 st->print(" Klass:");
2551 }
2552 t->dump_on(st);
2553 } else if (t == Type::MEMORY) {
2554 st->print(" Memory:");
2555 MemNode::dump_adr_type(this, adr_type(), st);
2556 } else if (Verbose || WizardMode) {
2557 st->print(" Type:");
2558 if (t) {
2559 t->dump_on(st);
2560 } else {
2561 st->print("no type");
2562 }
2563 } else if (t->isa_vect() && this->is_MachSpillCopy()) {
2564 // Dump MachSpillcopy vector type.
2565 t->dump_on(st);
2566 }
2567 if (is_new) {
2568 DEBUG_ONLY(dump_orig(st));
2569 Node_Notes* nn = C->node_notes_at(_idx);
2570 if (nn != nullptr && !nn->is_clear()) {
2571 if (nn->jvms() != nullptr) {
2572 st->print(" !jvms:");
2573 nn->jvms()->dump_spec(st);
2574 }
2575 }
2576 }
2577 if (suffix) st->print("%s", suffix);
2578 C->_in_dump_cnt--;
2579 }
2580
2581 // call from debugger: dump node to tty with newline
2582 void Node::dump() const {
2583 dump("\n");
2584 }
2585
2586 //------------------------------dump_req--------------------------------------
2587 void Node::dump_req(outputStream* st, DumpConfig* dc) const {
2588 // Dump the required input edges
2589 for (uint i = 0; i < req(); i++) { // For all required inputs
2590 Node* d = in(i);
2591 if (d == nullptr) {
2592 st->print("_ ");
2593 } else if (not_a_node(d)) {
2594 st->print("not_a_node "); // uninitialized, sentinel, garbage, etc.
2595 } else {
2596 d->dump_idx(false, st, dc);
2597 st->print(" ");
2598 }
2599 }
2600 }
2601
2602
2603 //------------------------------dump_prec-------------------------------------
2604 void Node::dump_prec(outputStream* st, DumpConfig* dc) const {
2605 // Dump the precedence edges
2606 int any_prec = 0;
2607 for (uint i = req(); i < len(); i++) { // For all precedence inputs
2608 Node* p = in(i);
2609 if (p != nullptr) {
2610 if (!any_prec++) st->print(" |");
2611 if (not_a_node(p)) { st->print("not_a_node "); continue; }
2612 p->dump_idx(false, st, dc);
2613 st->print(" ");
2614 }
2615 }
2616 }
2617
2618 //------------------------------dump_out--------------------------------------
2619 void Node::dump_out(outputStream* st, DumpConfig* dc) const {
2620 // Delimit the output edges
2621 st->print(" [[ ");
2622 // Dump the output edges
2623 for (uint i = 0; i < _outcnt; i++) { // For all outputs
2624 Node* u = _out[i];
2625 if (u == nullptr) {
2626 st->print("_ ");
2627 } else if (not_a_node(u)) {
2628 st->print("not_a_node ");
2629 } else {
2630 u->dump_idx(false, st, dc);
2631 st->print(" ");
2632 }
2633 }
2634 st->print("]] ");
2635 }
2636
2637 //------------------------------dump-------------------------------------------
2638 // call from debugger: dump Node's inputs (or outputs if d negative)
2639 void Node::dump(int d) const {
2640 dump_bfs(abs(d), nullptr, (d > 0) ? "+$" : "-$");
2641 }
2642
2643 //------------------------------dump_ctrl--------------------------------------
2644 // call from debugger: dump Node's control inputs (or outputs if d negative)
2645 void Node::dump_ctrl(int d) const {
2646 dump_bfs(abs(d), nullptr, (d > 0) ? "+$c" : "-$c");
2647 }
2648
2649 //-----------------------------dump_compact------------------------------------
2650 void Node::dump_comp() const {
2651 this->dump_comp("\n");
2652 }
2653
2654 //-----------------------------dump_compact------------------------------------
2655 // Dump a Node in compact representation, i.e., just print its name and index.
2656 // Nodes can specify additional specifics to print in compact representation by
2657 // implementing dump_compact_spec.
2658 void Node::dump_comp(const char* suffix, outputStream *st) const {
2659 Compile* C = Compile::current();
2660 C->_in_dump_cnt++;
2661 st->print("%s(%d)", Name(), _idx);
2662 this->dump_compact_spec(st);
2663 if (suffix) {
2664 st->print("%s", suffix);
2665 }
2666 C->_in_dump_cnt--;
2667 }
2668
2669 // VERIFICATION CODE
2670 // Verify all nodes if verify_depth is negative
2671 void Node::verify(int verify_depth, VectorSet& visited, Node_List& worklist) {
2672 assert(verify_depth != 0, "depth should not be 0");
2673 Compile* C = Compile::current();
2674 uint last_index_on_current_depth = worklist.size() - 1;
2675 verify_depth--; // Visiting the first node on depth 1
2676 // Only add nodes to worklist if verify_depth is negative (visit all nodes) or greater than 0
2677 bool add_to_worklist = verify_depth != 0;
2678
2679 for (uint list_index = 0; list_index < worklist.size(); list_index++) {
2680 Node* n = worklist[list_index];
2681
2682 if (n->is_Con() && n->bottom_type() == Type::TOP) {
2683 if (C->cached_top_node() == nullptr) {
2684 C->set_cached_top_node((Node*)n);
2685 }
2686 assert(C->cached_top_node() == n, "TOP node must be unique");
2687 }
2688
2689 uint in_len = n->len();
2690 for (uint i = 0; i < in_len; i++) {
2691 Node* x = n->_in[i];
2692 if (!x || x->is_top()) {
2693 continue;
2694 }
2695
2696 // Verify my input has a def-use edge to me
2697 // Count use-def edges from n to x
2698 int cnt = 1;
2699 for (uint j = 0; j < i; j++) {
2700 if (n->_in[j] == x) {
2701 cnt++;
2702 break;
2703 }
2704 }
2705 if (cnt == 2) {
2706 // x is already checked as n's previous input, skip its duplicated def-use count checking
2707 continue;
2708 }
2709 for (uint j = i + 1; j < in_len; j++) {
2710 if (n->_in[j] == x) {
2711 cnt++;
2712 }
2713 }
2714
2715 // Count def-use edges from x to n
2716 uint max = x->_outcnt;
2717 for (uint k = 0; k < max; k++) {
2718 if (x->_out[k] == n) {
2719 cnt--;
2720 }
2721 }
2722 assert(cnt == 0, "mismatched def-use edge counts");
2723
2724 if (add_to_worklist && !visited.test_set(x->_idx)) {
2725 worklist.push(x);
2726 }
2727 }
2728
2729 if (verify_depth > 0 && list_index == last_index_on_current_depth) {
2730 // All nodes on this depth were processed and its inputs are on the worklist. Decrement verify_depth and
2731 // store the current last list index which is the last node in the list with the new depth. All nodes
2732 // added afterwards will have a new depth again. Stop adding new nodes if depth limit is reached (=0).
2733 verify_depth--;
2734 if (verify_depth == 0) {
2735 add_to_worklist = false;
2736 }
2737 last_index_on_current_depth = worklist.size() - 1;
2738 }
2739 }
2740 }
2741 #endif // not PRODUCT
2742
2743 //------------------------------Registers--------------------------------------
2744 // Do we Match on this edge index or not? Generally false for Control
2745 // and true for everything else. Weird for calls & returns.
2746 uint Node::match_edge(uint idx) const {
2747 return idx; // True for other than index 0 (control)
2748 }
2749
2750 // Register classes are defined for specific machines
2751 const RegMask &Node::out_RegMask() const {
2752 ShouldNotCallThis();
2753 return RegMask::Empty;
2754 }
2755
2756 const RegMask &Node::in_RegMask(uint) const {
2757 ShouldNotCallThis();
2758 return RegMask::Empty;
2759 }
2760
2761 void Node_Array::grow(uint i) {
2762 assert(_max > 0, "invariant");
2763 uint old = _max;
2764 _max = next_power_of_2(i);
2765 _nodes = (Node**)_a->Arealloc( _nodes, old*sizeof(Node*),_max*sizeof(Node*));
2766 Copy::zero_to_bytes( &_nodes[old], (_max-old)*sizeof(Node*) );
2767 }
2768
2769 void Node_Array::insert(uint i, Node* n) {
2770 if (_nodes[_max - 1]) {
2771 grow(_max);
2772 }
2773 Copy::conjoint_words_to_higher((HeapWord*)&_nodes[i], (HeapWord*)&_nodes[i + 1], ((_max - i - 1) * sizeof(Node*)));
2774 _nodes[i] = n;
2775 }
2776
2777 void Node_Array::remove(uint i) {
2778 Copy::conjoint_words_to_lower((HeapWord*)&_nodes[i + 1], (HeapWord*)&_nodes[i], ((_max - i - 1) * sizeof(Node*)));
2779 _nodes[_max - 1] = nullptr;
2780 }
2781
2782 void Node_Array::dump() const {
2783 #ifndef PRODUCT
2784 for (uint i = 0; i < _max; i++) {
2785 Node* nn = _nodes[i];
2786 if (nn != nullptr) {
2787 tty->print("%5d--> ",i); nn->dump();
2788 }
2789 }
2790 #endif
2791 }
2792
2793 //--------------------------is_iteratively_computed------------------------------
2794 // Operation appears to be iteratively computed (such as an induction variable)
2795 // It is possible for this operation to return false for a loop-varying
2796 // value, if it appears (by local graph inspection) to be computed by a simple conditional.
2797 bool Node::is_iteratively_computed() {
2798 if (ideal_reg()) { // does operation have a result register?
2799 for (uint i = 1; i < req(); i++) {
2800 Node* n = in(i);
2801 if (n != nullptr && n->is_Phi()) {
2802 for (uint j = 1; j < n->req(); j++) {
2803 if (n->in(j) == this) {
2804 return true;
2805 }
2806 }
2807 }
2808 }
2809 }
2810 return false;
2811 }
2812
2813 //--------------------------find_similar------------------------------
2814 // Return a node with opcode "opc" and same inputs as "this" if one can
2815 // be found; Otherwise return null;
2816 Node* Node::find_similar(int opc) {
2817 if (req() >= 2) {
2818 Node* def = in(1);
2819 if (def && def->outcnt() >= 2) {
2820 for (DUIterator_Fast dmax, i = def->fast_outs(dmax); i < dmax; i++) {
2821 Node* use = def->fast_out(i);
2822 if (use != this &&
2823 use->Opcode() == opc &&
2824 use->req() == req()) {
2825 uint j;
2826 for (j = 0; j < use->req(); j++) {
2827 if (use->in(j) != in(j)) {
2828 break;
2829 }
2830 }
2831 if (j == use->req()) {
2832 return use;
2833 }
2834 }
2835 }
2836 }
2837 }
2838 return nullptr;
2839 }
2840
2841
2842 //--------------------------unique_ctrl_out_or_null-------------------------
2843 // Return the unique control out if only one. Null if none or more than one.
2844 Node* Node::unique_ctrl_out_or_null() const {
2845 Node* found = nullptr;
2846 for (uint i = 0; i < outcnt(); i++) {
2847 Node* use = raw_out(i);
2848 if (use->is_CFG() && use != this) {
2849 if (found != nullptr) {
2850 return nullptr;
2851 }
2852 found = use;
2853 }
2854 }
2855 return found;
2856 }
2857
2858 //--------------------------unique_ctrl_out------------------------------
2859 // Return the unique control out. Asserts if none or more than one control out.
2860 Node* Node::unique_ctrl_out() const {
2861 Node* ctrl = unique_ctrl_out_or_null();
2862 assert(ctrl != nullptr, "control out is assumed to be unique");
2863 return ctrl;
2864 }
2865
2866 void Node::ensure_control_or_add_prec(Node* c) {
2867 if (in(0) == nullptr) {
2868 set_req(0, c);
2869 } else if (in(0) != c) {
2870 add_prec(c);
2871 }
2872 }
2873
2874 bool Node::is_dead_loop_safe() const {
2875 if (is_Phi()) {
2876 return true;
2877 }
2878 if (is_Proj() && in(0) == nullptr) {
2879 return true;
2880 }
2881 if ((_flags & (Flag_is_dead_loop_safe | Flag_is_Con)) != 0) {
2882 if (!is_Proj()) {
2883 return true;
2884 }
2885 if (in(0)->is_Allocate()) {
2886 return false;
2887 }
2888 // MemNode::can_see_stored_value() peeks through the boxing call
2889 if (in(0)->is_CallStaticJava() && in(0)->as_CallStaticJava()->is_boxing_method()) {
2890 return false;
2891 }
2892 return true;
2893 }
2894 return false;
2895 }
2896
2897 //=============================================================================
2898 //------------------------------yank-------------------------------------------
2899 // Find and remove
2900 void Node_List::yank( Node *n ) {
2901 uint i;
2902 for (i = 0; i < _cnt; i++) {
2903 if (_nodes[i] == n) {
2904 break;
2905 }
2906 }
2907
2908 if (i < _cnt) {
2909 _nodes[i] = _nodes[--_cnt];
2910 }
2911 }
2912
2913 //------------------------------dump-------------------------------------------
2914 void Node_List::dump() const {
2915 #ifndef PRODUCT
2916 for (uint i = 0; i < _cnt; i++) {
2917 if (_nodes[i]) {
2918 tty->print("%5d--> ", i);
2919 _nodes[i]->dump();
2920 }
2921 }
2922 #endif
2923 }
2924
2925 void Node_List::dump_simple() const {
2926 #ifndef PRODUCT
2927 for (uint i = 0; i < _cnt; i++) {
2928 if( _nodes[i] ) {
2929 tty->print(" %d", _nodes[i]->_idx);
2930 } else {
2931 tty->print(" null");
2932 }
2933 }
2934 #endif
2935 }
2936
2937 //=============================================================================
2938 //------------------------------remove-----------------------------------------
2939 void Unique_Node_List::remove(Node* n) {
2940 if (_in_worklist.test(n->_idx)) {
2941 for (uint i = 0; i < size(); i++) {
2942 if (_nodes[i] == n) {
2943 map(i, Node_List::pop());
2944 _in_worklist.remove(n->_idx);
2945 return;
2946 }
2947 }
2948 ShouldNotReachHere();
2949 }
2950 }
2951
2952 //-----------------------remove_useless_nodes----------------------------------
2953 // Remove useless nodes from worklist
2954 void Unique_Node_List::remove_useless_nodes(VectorSet &useful) {
2955 for (uint i = 0; i < size(); ++i) {
2956 Node *n = at(i);
2957 assert( n != nullptr, "Did not expect null entries in worklist");
2958 if (!useful.test(n->_idx)) {
2959 _in_worklist.remove(n->_idx);
2960 map(i, Node_List::pop());
2961 --i; // Visit popped node
2962 // If it was last entry, loop terminates since size() was also reduced
2963 }
2964 }
2965 }
2966
2967 //=============================================================================
2968 void Node_Stack::grow() {
2969 size_t old_top = pointer_delta(_inode_top,_inodes,sizeof(INode)); // save _top
2970 size_t old_max = pointer_delta(_inode_max,_inodes,sizeof(INode));
2971 size_t max = old_max << 1; // max * 2
2972 _inodes = REALLOC_ARENA_ARRAY(_a, INode, _inodes, old_max, max);
2973 _inode_max = _inodes + max;
2974 _inode_top = _inodes + old_top; // restore _top
2975 }
2976
2977 // Node_Stack is used to map nodes.
2978 Node* Node_Stack::find(uint idx) const {
2979 uint sz = size();
2980 for (uint i = 0; i < sz; i++) {
2981 if (idx == index_at(i)) {
2982 return node_at(i);
2983 }
2984 }
2985 return nullptr;
2986 }
2987
2988 //=============================================================================
2989 uint TypeNode::size_of() const { return sizeof(*this); }
2990 #ifndef PRODUCT
2991 void TypeNode::dump_spec(outputStream *st) const {
2992 if (!Verbose && !WizardMode) {
2993 // standard dump does this in Verbose and WizardMode
2994 st->print(" #"); _type->dump_on(st);
2995 }
2996 }
2997
2998 void TypeNode::dump_compact_spec(outputStream *st) const {
2999 st->print("#");
3000 _type->dump_on(st);
3001 }
3002 #endif
3003 uint TypeNode::hash() const {
3004 return Node::hash() + _type->hash();
3005 }
3006 bool TypeNode::cmp(const Node& n) const {
3007 return !Type::cmp(_type, ((TypeNode&)n)._type);
3008 }
3009 const Type* TypeNode::bottom_type() const { return _type; }
3010 const Type* TypeNode::Value(PhaseGVN* phase) const { return _type; }
3011
3012 //------------------------------ideal_reg--------------------------------------
3013 uint TypeNode::ideal_reg() const {
3014 return _type->ideal_reg();
3015 }