1 /*
2 * Copyright (c) 1997, 2022, 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/inlinetypenode.hpp"
37 #include "opto/loopnode.hpp"
38 #include "opto/machnode.hpp"
39 #include "opto/matcher.hpp"
40 #include "opto/node.hpp"
41 #include "opto/opcodes.hpp"
42 #include "opto/regmask.hpp"
43 #include "opto/rootnode.hpp"
44 #include "opto/type.hpp"
45 #include "utilities/copy.hpp"
46 #include "utilities/macros.hpp"
47 #include "utilities/powerOfTwo.hpp"
48 #include "utilities/stringUtils.hpp"
49
50 class RegMask;
51 // #include "phase.hpp"
52 class PhaseTransform;
53 class PhaseGVN;
54
55 // Arena we are currently building Nodes in
56 const uint Node::NotAMachineReg = 0xffff0000;
57
58 #ifndef PRODUCT
59 extern int nodes_created;
60 #endif
61 #ifdef __clang__
62 #pragma clang diagnostic push
63 #pragma GCC diagnostic ignored "-Wuninitialized"
64 #endif
65
66 #ifdef ASSERT
67
68 //-------------------------- construct_node------------------------------------
69 // Set a breakpoint here to identify where a particular node index is built.
70 void Node::verify_construction() {
71 _debug_orig = NULL;
72 int old_debug_idx = Compile::debug_idx();
73 int new_debug_idx = old_debug_idx + 1;
74 if (new_debug_idx > 0) {
75 // Arrange that the lowest five decimal digits of _debug_idx
76 // will repeat those of _idx. In case this is somehow pathological,
77 // we continue to assign negative numbers (!) consecutively.
78 const int mod = 100000;
79 int bump = (int)(_idx - new_debug_idx) % mod;
80 if (bump < 0) {
81 bump += mod;
82 }
83 assert(bump >= 0 && bump < mod, "");
84 new_debug_idx += bump;
85 }
86 Compile::set_debug_idx(new_debug_idx);
87 set_debug_idx(new_debug_idx);
88 Compile* C = Compile::current();
89 assert(C->unique() < (INT_MAX - 1), "Node limit exceeded INT_MAX");
90 if (!C->phase_optimize_finished()) {
91 // Only check assert during parsing and optimization phase. Skip it while generating code.
92 assert(C->live_nodes() <= C->max_node_limit(), "Live Node limit exceeded limit");
93 }
94 if (BreakAtNode != 0 && (_debug_idx == BreakAtNode || (int)_idx == BreakAtNode)) {
95 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=%d", _idx, _debug_idx);
96 BREAKPOINT;
97 }
98 #if OPTO_DU_ITERATOR_ASSERT
99 _last_del = NULL;
100 _del_tick = 0;
101 #endif
102 _hash_lock = 0;
103 }
104
105
106 // #ifdef ASSERT ...
107
108 #if OPTO_DU_ITERATOR_ASSERT
109 void DUIterator_Common::sample(const Node* node) {
110 _vdui = VerifyDUIterators;
111 _node = node;
112 _outcnt = node->_outcnt;
113 _del_tick = node->_del_tick;
114 _last = NULL;
115 }
116
117 void DUIterator_Common::verify(const Node* node, bool at_end_ok) {
118 assert(_node == node, "consistent iterator source");
119 assert(_del_tick == node->_del_tick, "no unexpected deletions allowed");
120 }
121
122 void DUIterator_Common::verify_resync() {
123 // Ensure that the loop body has just deleted the last guy produced.
124 const Node* node = _node;
125 // Ensure that at least one copy of the last-seen edge was deleted.
126 // Note: It is OK to delete multiple copies of the last-seen edge.
127 // Unfortunately, we have no way to verify that all the deletions delete
128 // that same edge. On this point we must use the Honor System.
129 assert(node->_del_tick >= _del_tick+1, "must have deleted an edge");
130 assert(node->_last_del == _last, "must have deleted the edge just produced");
131 // We liked this deletion, so accept the resulting outcnt and tick.
132 _outcnt = node->_outcnt;
133 _del_tick = node->_del_tick;
134 }
135
136 void DUIterator_Common::reset(const DUIterator_Common& that) {
137 if (this == &that) return; // ignore assignment to self
138 if (!_vdui) {
139 // We need to initialize everything, overwriting garbage values.
140 _last = that._last;
141 _vdui = that._vdui;
142 }
143 // Note: It is legal (though odd) for an iterator over some node x
144 // to be reassigned to iterate over another node y. Some doubly-nested
145 // progress loops depend on being able to do this.
146 const Node* node = that._node;
147 // Re-initialize everything, except _last.
148 _node = node;
149 _outcnt = node->_outcnt;
150 _del_tick = node->_del_tick;
151 }
152
153 void DUIterator::sample(const Node* node) {
154 DUIterator_Common::sample(node); // Initialize the assertion data.
155 _refresh_tick = 0; // No refreshes have happened, as yet.
156 }
157
158 void DUIterator::verify(const Node* node, bool at_end_ok) {
159 DUIterator_Common::verify(node, at_end_ok);
160 assert(_idx < node->_outcnt + (uint)at_end_ok, "idx in range");
161 }
162
163 void DUIterator::verify_increment() {
164 if (_refresh_tick & 1) {
165 // We have refreshed the index during this loop.
166 // Fix up _idx to meet asserts.
167 if (_idx > _outcnt) _idx = _outcnt;
168 }
169 verify(_node, true);
170 }
171
172 void DUIterator::verify_resync() {
173 // Note: We do not assert on _outcnt, because insertions are OK here.
174 DUIterator_Common::verify_resync();
175 // Make sure we are still in sync, possibly with no more out-edges:
176 verify(_node, true);
177 }
178
179 void DUIterator::reset(const DUIterator& that) {
180 if (this == &that) return; // self assignment is always a no-op
181 assert(that._refresh_tick == 0, "assign only the result of Node::outs()");
182 assert(that._idx == 0, "assign only the result of Node::outs()");
183 assert(_idx == that._idx, "already assigned _idx");
184 if (!_vdui) {
185 // We need to initialize everything, overwriting garbage values.
186 sample(that._node);
187 } else {
188 DUIterator_Common::reset(that);
189 if (_refresh_tick & 1) {
190 _refresh_tick++; // Clear the "was refreshed" flag.
191 }
192 assert(_refresh_tick < 2*100000, "DU iteration must converge quickly");
193 }
194 }
195
196 void DUIterator::refresh() {
197 DUIterator_Common::sample(_node); // Re-fetch assertion data.
198 _refresh_tick |= 1; // Set the "was refreshed" flag.
199 }
200
201 void DUIterator::verify_finish() {
202 // If the loop has killed the node, do not require it to re-run.
203 if (_node->_outcnt == 0) _refresh_tick &= ~1;
204 // If this assert triggers, it means that a loop used refresh_out_pos
205 // to re-synch an iteration index, but the loop did not correctly
206 // re-run itself, using a "while (progress)" construct.
207 // This iterator enforces the rule that you must keep trying the loop
208 // until it "runs clean" without any need for refreshing.
209 assert(!(_refresh_tick & 1), "the loop must run once with no refreshing");
210 }
211
212
213 void DUIterator_Fast::verify(const Node* node, bool at_end_ok) {
214 DUIterator_Common::verify(node, at_end_ok);
215 Node** out = node->_out;
216 uint cnt = node->_outcnt;
217 assert(cnt == _outcnt, "no insertions allowed");
218 assert(_outp >= out && _outp <= out + cnt - !at_end_ok, "outp in range");
219 // This last check is carefully designed to work for NO_OUT_ARRAY.
220 }
221
222 void DUIterator_Fast::verify_limit() {
223 const Node* node = _node;
224 verify(node, true);
225 assert(_outp == node->_out + node->_outcnt, "limit still correct");
226 }
227
228 void DUIterator_Fast::verify_resync() {
229 const Node* node = _node;
230 if (_outp == node->_out + _outcnt) {
231 // Note that the limit imax, not the pointer i, gets updated with the
232 // exact count of deletions. (For the pointer it's always "--i".)
233 assert(node->_outcnt+node->_del_tick == _outcnt+_del_tick, "no insertions allowed with deletion(s)");
234 // This is a limit pointer, with a name like "imax".
235 // Fudge the _last field so that the common assert will be happy.
236 _last = (Node*) node->_last_del;
237 DUIterator_Common::verify_resync();
238 } else {
239 assert(node->_outcnt < _outcnt, "no insertions allowed with deletion(s)");
240 // A normal internal pointer.
241 DUIterator_Common::verify_resync();
242 // Make sure we are still in sync, possibly with no more out-edges:
243 verify(node, true);
244 }
245 }
246
247 void DUIterator_Fast::verify_relimit(uint n) {
248 const Node* node = _node;
249 assert((int)n > 0, "use imax -= n only with a positive count");
250 // This must be a limit pointer, with a name like "imax".
251 assert(_outp == node->_out + node->_outcnt, "apply -= only to a limit (imax)");
252 // The reported number of deletions must match what the node saw.
253 assert(node->_del_tick == _del_tick + n, "must have deleted n edges");
254 // Fudge the _last field so that the common assert will be happy.
255 _last = (Node*) node->_last_del;
256 DUIterator_Common::verify_resync();
257 }
258
259 void DUIterator_Fast::reset(const DUIterator_Fast& that) {
260 assert(_outp == that._outp, "already assigned _outp");
261 DUIterator_Common::reset(that);
262 }
263
264 void DUIterator_Last::verify(const Node* node, bool at_end_ok) {
265 // at_end_ok means the _outp is allowed to underflow by 1
266 _outp += at_end_ok;
267 DUIterator_Fast::verify(node, at_end_ok); // check _del_tick, etc.
268 _outp -= at_end_ok;
269 assert(_outp == (node->_out + node->_outcnt) - 1, "pointer must point to end of nodes");
270 }
271
272 void DUIterator_Last::verify_limit() {
273 // Do not require the limit address to be resynched.
274 //verify(node, true);
275 assert(_outp == _node->_out, "limit still correct");
276 }
277
278 void DUIterator_Last::verify_step(uint num_edges) {
279 assert((int)num_edges > 0, "need non-zero edge count for loop progress");
280 _outcnt -= num_edges;
281 _del_tick += num_edges;
282 // Make sure we are still in sync, possibly with no more out-edges:
283 const Node* node = _node;
284 verify(node, true);
285 assert(node->_last_del == _last, "must have deleted the edge just produced");
286 }
287
288 #endif //OPTO_DU_ITERATOR_ASSERT
289
290
291 #endif //ASSERT
292
293
294 // This constant used to initialize _out may be any non-null value.
295 // The value NULL is reserved for the top node only.
296 #define NO_OUT_ARRAY ((Node**)-1)
297
298 // Out-of-line code from node constructors.
299 // Executed only when extra debug info. is being passed around.
300 static void init_node_notes(Compile* C, int idx, Node_Notes* nn) {
301 C->set_node_notes_at(idx, nn);
302 }
303
304 // Shared initialization code.
305 inline int Node::Init(int req) {
306 Compile* C = Compile::current();
307 int idx = C->next_unique();
308 NOT_PRODUCT(_igv_idx = C->next_igv_idx());
309
310 // Allocate memory for the necessary number of edges.
311 if (req > 0) {
312 // Allocate space for _in array to have double alignment.
313 _in = (Node **) ((char *) (C->node_arena()->AmallocWords(req * sizeof(void*))));
314 }
315 // If there are default notes floating around, capture them:
316 Node_Notes* nn = C->default_node_notes();
317 if (nn != NULL) init_node_notes(C, idx, nn);
318
319 // Note: At this point, C is dead,
320 // and we begin to initialize the new Node.
321
322 _cnt = _max = req;
323 _outcnt = _outmax = 0;
324 _class_id = Class_Node;
325 _flags = 0;
326 _out = NO_OUT_ARRAY;
327 return idx;
328 }
329
330 //------------------------------Node-------------------------------------------
331 // Create a Node, with a given number of required edges.
332 Node::Node(uint req)
333 : _idx(Init(req))
334 #ifdef ASSERT
335 , _parse_idx(_idx)
336 #endif
337 {
338 assert( req < Compile::current()->max_node_limit() - NodeLimitFudgeFactor, "Input limit exceeded" );
339 debug_only( verify_construction() );
340 NOT_PRODUCT(nodes_created++);
341 if (req == 0) {
342 _in = NULL;
343 } else {
344 Node** to = _in;
345 for(uint i = 0; i < req; i++) {
346 to[i] = NULL;
347 }
348 }
349 }
350
351 //------------------------------Node-------------------------------------------
352 Node::Node(Node *n0)
353 : _idx(Init(1))
354 #ifdef ASSERT
355 , _parse_idx(_idx)
356 #endif
357 {
358 debug_only( verify_construction() );
359 NOT_PRODUCT(nodes_created++);
360 assert( is_not_dead(n0), "can not use dead node");
361 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
362 }
363
364 //------------------------------Node-------------------------------------------
365 Node::Node(Node *n0, Node *n1)
366 : _idx(Init(2))
367 #ifdef ASSERT
368 , _parse_idx(_idx)
369 #endif
370 {
371 debug_only( verify_construction() );
372 NOT_PRODUCT(nodes_created++);
373 assert( is_not_dead(n0), "can not use dead node");
374 assert( is_not_dead(n1), "can not use dead node");
375 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
376 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
377 }
378
379 //------------------------------Node-------------------------------------------
380 Node::Node(Node *n0, Node *n1, Node *n2)
381 : _idx(Init(3))
382 #ifdef ASSERT
383 , _parse_idx(_idx)
384 #endif
385 {
386 debug_only( verify_construction() );
387 NOT_PRODUCT(nodes_created++);
388 assert( is_not_dead(n0), "can not use dead node");
389 assert( is_not_dead(n1), "can not use dead node");
390 assert( is_not_dead(n2), "can not use dead node");
391 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
392 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
393 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
394 }
395
396 //------------------------------Node-------------------------------------------
397 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3)
398 : _idx(Init(4))
399 #ifdef ASSERT
400 , _parse_idx(_idx)
401 #endif
402 {
403 debug_only( verify_construction() );
404 NOT_PRODUCT(nodes_created++);
405 assert( is_not_dead(n0), "can not use dead node");
406 assert( is_not_dead(n1), "can not use dead node");
407 assert( is_not_dead(n2), "can not use dead node");
408 assert( is_not_dead(n3), "can not use dead node");
409 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
410 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
411 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
412 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
413 }
414
415 //------------------------------Node-------------------------------------------
416 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3, Node *n4)
417 : _idx(Init(5))
418 #ifdef ASSERT
419 , _parse_idx(_idx)
420 #endif
421 {
422 debug_only( verify_construction() );
423 NOT_PRODUCT(nodes_created++);
424 assert( is_not_dead(n0), "can not use dead node");
425 assert( is_not_dead(n1), "can not use dead node");
426 assert( is_not_dead(n2), "can not use dead node");
427 assert( is_not_dead(n3), "can not use dead node");
428 assert( is_not_dead(n4), "can not use dead node");
429 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
430 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
431 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
432 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
433 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this);
434 }
435
436 //------------------------------Node-------------------------------------------
437 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3,
438 Node *n4, Node *n5)
439 : _idx(Init(6))
440 #ifdef ASSERT
441 , _parse_idx(_idx)
442 #endif
443 {
444 debug_only( verify_construction() );
445 NOT_PRODUCT(nodes_created++);
446 assert( is_not_dead(n0), "can not use dead node");
447 assert( is_not_dead(n1), "can not use dead node");
448 assert( is_not_dead(n2), "can not use dead node");
449 assert( is_not_dead(n3), "can not use dead node");
450 assert( is_not_dead(n4), "can not use dead node");
451 assert( is_not_dead(n5), "can not use dead node");
452 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
453 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
454 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
455 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
456 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this);
457 _in[5] = n5; if (n5 != NULL) n5->add_out((Node *)this);
458 }
459
460 //------------------------------Node-------------------------------------------
461 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3,
462 Node *n4, Node *n5, Node *n6)
463 : _idx(Init(7))
464 #ifdef ASSERT
465 , _parse_idx(_idx)
466 #endif
467 {
468 debug_only( verify_construction() );
469 NOT_PRODUCT(nodes_created++);
470 assert( is_not_dead(n0), "can not use dead node");
471 assert( is_not_dead(n1), "can not use dead node");
472 assert( is_not_dead(n2), "can not use dead node");
473 assert( is_not_dead(n3), "can not use dead node");
474 assert( is_not_dead(n4), "can not use dead node");
475 assert( is_not_dead(n5), "can not use dead node");
476 assert( is_not_dead(n6), "can not use dead node");
477 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
478 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
479 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
480 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
481 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this);
482 _in[5] = n5; if (n5 != NULL) n5->add_out((Node *)this);
483 _in[6] = n6; if (n6 != NULL) n6->add_out((Node *)this);
484 }
485
486 #ifdef __clang__
487 #pragma clang diagnostic pop
488 #endif
489
490
491 //------------------------------clone------------------------------------------
492 // Clone a Node.
493 Node *Node::clone() const {
494 Compile* C = Compile::current();
495 uint s = size_of(); // Size of inherited Node
496 Node *n = (Node*)C->node_arena()->AmallocWords(size_of() + _max*sizeof(Node*));
497 Copy::conjoint_words_to_lower((HeapWord*)this, (HeapWord*)n, s);
498 // Set the new input pointer array
499 n->_in = (Node**)(((char*)n)+s);
500 // Cannot share the old output pointer array, so kill it
501 n->_out = NO_OUT_ARRAY;
502 // And reset the counters to 0
503 n->_outcnt = 0;
504 n->_outmax = 0;
505 // Unlock this guy, since he is not in any hash table.
506 debug_only(n->_hash_lock = 0);
507 // Walk the old node's input list to duplicate its edges
508 uint i;
509 for( i = 0; i < len(); i++ ) {
510 Node *x = in(i);
511 n->_in[i] = x;
512 if (x != NULL) x->add_out(n);
513 }
514 if (is_macro()) {
515 C->add_macro_node(n);
516 }
517 if (is_expensive()) {
518 C->add_expensive_node(n);
519 }
520 if (for_post_loop_opts_igvn()) {
521 // Don't add cloned node to Compile::_for_post_loop_opts_igvn list automatically.
522 // If it is applicable, it will happen anyway when the cloned node is registered with IGVN.
523 n->remove_flag(Node::NodeFlags::Flag_for_post_loop_opts_igvn);
524 }
525 if (n->is_reduction()) {
526 // Do not copy reduction information. This must be explicitly set by the calling code.
527 n->remove_flag(Node::Flag_is_reduction);
528 }
529 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
530 bs->register_potential_barrier_node(n);
531
532 n->set_idx(C->next_unique()); // Get new unique index as well
533 NOT_PRODUCT(n->_igv_idx = C->next_igv_idx());
534 debug_only( n->verify_construction() );
535 NOT_PRODUCT(nodes_created++);
536 // Do not patch over the debug_idx of a clone, because it makes it
537 // impossible to break on the clone's moment of creation.
538 //debug_only( n->set_debug_idx( debug_idx() ) );
539
540 C->copy_node_notes_to(n, (Node*) this);
541
542 // MachNode clone
543 uint nopnds;
544 if (this->is_Mach() && (nopnds = this->as_Mach()->num_opnds()) > 0) {
545 MachNode *mach = n->as_Mach();
546 MachNode *mthis = this->as_Mach();
547 // Get address of _opnd_array.
548 // It should be the same offset since it is the clone of this node.
549 MachOper **from = mthis->_opnds;
550 MachOper **to = (MachOper **)((size_t)(&mach->_opnds) +
551 pointer_delta((const void*)from,
552 (const void*)(&mthis->_opnds), 1));
553 mach->_opnds = to;
554 for ( uint i = 0; i < nopnds; ++i ) {
555 to[i] = from[i]->clone();
556 }
557 }
558 if (n->is_Call()) {
559 // CallGenerator is linked to the original node.
560 CallGenerator* cg = n->as_Call()->generator();
561 if (cg != NULL) {
562 CallGenerator* cloned_cg = cg->with_call_node(n->as_Call());
563 n->as_Call()->set_generator(cloned_cg);
564
565 C->print_inlining_assert_ready();
566 C->print_inlining_move_to(cg);
567 C->print_inlining_update(cloned_cg);
568 }
569 }
570 if (n->is_SafePoint()) {
571 // Scalar replacement and macro expansion might modify the JVMState.
572 // Clone it to make sure it's not shared between SafePointNodes.
573 n->as_SafePoint()->clone_jvms(C);
574 n->as_SafePoint()->clone_replaced_nodes();
575 }
576 if (n->is_InlineType()) {
577 C->add_inline_type(n);
578 }
579 Compile::current()->record_modified_node(n);
580 return n; // Return the clone
581 }
582
583 //---------------------------setup_is_top--------------------------------------
584 // Call this when changing the top node, to reassert the invariants
585 // required by Node::is_top. See Compile::set_cached_top_node.
586 void Node::setup_is_top() {
587 if (this == (Node*)Compile::current()->top()) {
588 // This node has just become top. Kill its out array.
589 _outcnt = _outmax = 0;
590 _out = NULL; // marker value for top
591 assert(is_top(), "must be top");
592 } else {
593 if (_out == NULL) _out = NO_OUT_ARRAY;
594 assert(!is_top(), "must not be top");
595 }
596 }
597
598 //------------------------------~Node------------------------------------------
599 // Fancy destructor; eagerly attempt to reclaim Node numberings and storage
600 void Node::destruct(PhaseValues* phase) {
601 Compile* compile = (phase != NULL) ? phase->C : Compile::current();
602 if (phase != NULL && phase->is_IterGVN()) {
603 phase->is_IterGVN()->_worklist.remove(this);
604 }
605 // If this is the most recently created node, reclaim its index. Otherwise,
606 // record the node as dead to keep liveness information accurate.
607 if ((uint)_idx+1 == compile->unique()) {
608 compile->set_unique(compile->unique()-1);
609 } else {
610 compile->record_dead_node(_idx);
611 }
612 // Clear debug info:
613 Node_Notes* nn = compile->node_notes_at(_idx);
614 if (nn != NULL) nn->clear();
615 // Walk the input array, freeing the corresponding output edges
616 _cnt = _max; // forget req/prec distinction
617 uint i;
618 for( i = 0; i < _max; i++ ) {
619 set_req(i, NULL);
620 //assert(def->out(def->outcnt()-1) == (Node *)this,"bad def-use hacking in reclaim");
621 }
622 assert(outcnt() == 0, "deleting a node must not leave a dangling use");
623 // See if the input array was allocated just prior to the object
624 int edge_size = _max*sizeof(void*);
625 int out_edge_size = _outmax*sizeof(void*);
626 char *edge_end = ((char*)_in) + edge_size;
627 char *out_array = (char*)(_out == NO_OUT_ARRAY? NULL: _out);
628 int node_size = size_of();
629
630 // Free the output edge array
631 if (out_edge_size > 0) {
632 compile->node_arena()->Afree(out_array, out_edge_size);
633 }
634
635 // Free the input edge array and the node itself
636 if( edge_end == (char*)this ) {
637 // It was; free the input array and object all in one hit
638 #ifndef ASSERT
639 compile->node_arena()->Afree(_in,edge_size+node_size);
640 #endif
641 } else {
642 // Free just the input array
643 compile->node_arena()->Afree(_in,edge_size);
644
645 // Free just the object
646 #ifndef ASSERT
647 compile->node_arena()->Afree(this,node_size);
648 #endif
649 }
650 if (is_macro()) {
651 compile->remove_macro_node(this);
652 }
653 if (is_expensive()) {
654 compile->remove_expensive_node(this);
655 }
656 if (Opcode() == Op_Opaque4) {
657 compile->remove_skeleton_predicate_opaq(this);
658 }
659 if (for_post_loop_opts_igvn()) {
660 compile->remove_from_post_loop_opts_igvn(this);
661 }
662 if (is_InlineType()) {
663 compile->remove_inline_type(this);
664 }
665
666 if (is_SafePoint()) {
667 as_SafePoint()->delete_replaced_nodes();
668
669 if (is_CallStaticJava()) {
670 compile->remove_unstable_if_trap(as_CallStaticJava(), false);
671 }
672 }
673 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
674 bs->unregister_potential_barrier_node(this);
675 #ifdef ASSERT
676 // We will not actually delete the storage, but we'll make the node unusable.
677 *(address*)this = badAddress; // smash the C++ vtbl, probably
678 _in = _out = (Node**) badAddress;
679 _max = _cnt = _outmax = _outcnt = 0;
680 compile->remove_modified_node(this);
681 #endif
682 }
683
684 //------------------------------grow-------------------------------------------
685 // Grow the input array, making space for more edges
686 void Node::grow(uint len) {
687 Arena* arena = Compile::current()->node_arena();
688 uint new_max = _max;
689 if( new_max == 0 ) {
690 _max = 4;
691 _in = (Node**)arena->Amalloc(4*sizeof(Node*));
692 Node** to = _in;
693 to[0] = NULL;
694 to[1] = NULL;
695 to[2] = NULL;
696 to[3] = NULL;
697 return;
698 }
699 new_max = next_power_of_2(len);
700 // Trimming to limit allows a uint8 to handle up to 255 edges.
701 // Previously I was using only powers-of-2 which peaked at 128 edges.
702 //if( new_max >= limit ) new_max = limit-1;
703 _in = (Node**)arena->Arealloc(_in, _max*sizeof(Node*), new_max*sizeof(Node*));
704 Copy::zero_to_bytes(&_in[_max], (new_max-_max)*sizeof(Node*)); // NULL all new space
705 _max = new_max; // Record new max length
706 // This assertion makes sure that Node::_max is wide enough to
707 // represent the numerical value of new_max.
708 assert(_max == new_max && _max > len, "int width of _max is too small");
709 }
710
711 //-----------------------------out_grow----------------------------------------
712 // Grow the input array, making space for more edges
713 void Node::out_grow( uint len ) {
714 assert(!is_top(), "cannot grow a top node's out array");
715 Arena* arena = Compile::current()->node_arena();
716 uint new_max = _outmax;
717 if( new_max == 0 ) {
718 _outmax = 4;
719 _out = (Node **)arena->Amalloc(4*sizeof(Node*));
720 return;
721 }
722 new_max = next_power_of_2(len);
723 // Trimming to limit allows a uint8 to handle up to 255 edges.
724 // Previously I was using only powers-of-2 which peaked at 128 edges.
725 //if( new_max >= limit ) new_max = limit-1;
726 assert(_out != NULL && _out != NO_OUT_ARRAY, "out must have sensible value");
727 _out = (Node**)arena->Arealloc(_out,_outmax*sizeof(Node*),new_max*sizeof(Node*));
728 //Copy::zero_to_bytes(&_out[_outmax], (new_max-_outmax)*sizeof(Node*)); // NULL all new space
729 _outmax = new_max; // Record new max length
730 // This assertion makes sure that Node::_max is wide enough to
731 // represent the numerical value of new_max.
732 assert(_outmax == new_max && _outmax > len, "int width of _outmax is too small");
733 }
734
735 #ifdef ASSERT
736 //------------------------------is_dead----------------------------------------
737 bool Node::is_dead() const {
738 // Mach and pinch point nodes may look like dead.
739 if( is_top() || is_Mach() || (Opcode() == Op_Node && _outcnt > 0) )
740 return false;
741 for( uint i = 0; i < _max; i++ )
742 if( _in[i] != NULL )
743 return false;
744 return true;
745 }
746
747 bool Node::is_reachable_from_root() const {
748 ResourceMark rm;
749 Unique_Node_List wq;
750 wq.push((Node*)this);
751 RootNode* root = Compile::current()->root();
752 for (uint i = 0; i < wq.size(); i++) {
753 Node* m = wq.at(i);
754 if (m == root) {
755 return true;
756 }
757 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
758 Node* u = m->fast_out(j);
759 wq.push(u);
760 }
761 }
762 return false;
763 }
764 #endif
765
766 //------------------------------is_unreachable---------------------------------
767 bool Node::is_unreachable(PhaseIterGVN &igvn) const {
768 assert(!is_Mach(), "doesn't work with MachNodes");
769 return outcnt() == 0 || igvn.type(this) == Type::TOP || (in(0) != NULL && in(0)->is_top());
770 }
771
772 //------------------------------add_req----------------------------------------
773 // Add a new required input at the end
774 void Node::add_req( Node *n ) {
775 assert( is_not_dead(n), "can not use dead node");
776
777 // Look to see if I can move precedence down one without reallocating
778 if( (_cnt >= _max) || (in(_max-1) != NULL) )
779 grow( _max+1 );
780
781 // Find a precedence edge to move
782 if( in(_cnt) != NULL ) { // Next precedence edge is busy?
783 uint i;
784 for( i=_cnt; i<_max; i++ )
785 if( in(i) == NULL ) // Find the NULL at end of prec edge list
786 break; // There must be one, since we grew the array
787 _in[i] = in(_cnt); // Move prec over, making space for req edge
788 }
789 _in[_cnt++] = n; // Stuff over old prec edge
790 if (n != NULL) n->add_out((Node *)this);
791 Compile::current()->record_modified_node(this);
792 }
793
794 //---------------------------add_req_batch-------------------------------------
795 // Add a new required input at the end
796 void Node::add_req_batch( Node *n, uint m ) {
797 assert( is_not_dead(n), "can not use dead node");
798 // check various edge cases
799 if ((int)m <= 1) {
800 assert((int)m >= 0, "oob");
801 if (m != 0) add_req(n);
802 return;
803 }
804
805 // Look to see if I can move precedence down one without reallocating
806 if( (_cnt+m) > _max || _in[_max-m] )
807 grow( _max+m );
808
809 // Find a precedence edge to move
810 if( _in[_cnt] != NULL ) { // Next precedence edge is busy?
811 uint i;
812 for( i=_cnt; i<_max; i++ )
813 if( _in[i] == NULL ) // Find the NULL at end of prec edge list
814 break; // There must be one, since we grew the array
815 // Slide all the precs over by m positions (assume #prec << m).
816 Copy::conjoint_words_to_higher((HeapWord*)&_in[_cnt], (HeapWord*)&_in[_cnt+m], ((i-_cnt)*sizeof(Node*)));
817 }
818
819 // Stuff over the old prec edges
820 for(uint i=0; i<m; i++ ) {
821 _in[_cnt++] = n;
822 }
823
824 // Insert multiple out edges on the node.
825 if (n != NULL && !n->is_top()) {
826 for(uint i=0; i<m; i++ ) {
827 n->add_out((Node *)this);
828 }
829 }
830 Compile::current()->record_modified_node(this);
831 }
832
833 //------------------------------del_req----------------------------------------
834 // Delete the required edge and compact the edge array
835 void Node::del_req( uint idx ) {
836 assert( idx < _cnt, "oob");
837 assert( !VerifyHashTableKeys || _hash_lock == 0,
838 "remove node from hash table before modifying it");
839 // First remove corresponding def-use edge
840 Node *n = in(idx);
841 if (n != NULL) n->del_out((Node *)this);
842 _in[idx] = in(--_cnt); // Compact the array
843 // Avoid spec violation: Gap in prec edges.
844 close_prec_gap_at(_cnt);
845 Compile::current()->record_modified_node(this);
846 }
847
848 //------------------------------del_req_ordered--------------------------------
849 // Delete the required edge and compact the edge array with preserved order
850 void Node::del_req_ordered( uint idx ) {
851 assert( idx < _cnt, "oob");
852 assert( !VerifyHashTableKeys || _hash_lock == 0,
853 "remove node from hash table before modifying it");
854 // First remove corresponding def-use edge
855 Node *n = in(idx);
856 if (n != NULL) n->del_out((Node *)this);
857 if (idx < --_cnt) { // Not last edge ?
858 Copy::conjoint_words_to_lower((HeapWord*)&_in[idx+1], (HeapWord*)&_in[idx], ((_cnt-idx)*sizeof(Node*)));
859 }
860 // Avoid spec violation: Gap in prec edges.
861 close_prec_gap_at(_cnt);
862 Compile::current()->record_modified_node(this);
863 }
864
865 //------------------------------ins_req----------------------------------------
866 // Insert a new required input at the end
867 void Node::ins_req( uint idx, Node *n ) {
868 assert( is_not_dead(n), "can not use dead node");
869 add_req(NULL); // Make space
870 assert( idx < _max, "Must have allocated enough space");
871 // Slide over
872 if(_cnt-idx-1 > 0) {
873 Copy::conjoint_words_to_higher((HeapWord*)&_in[idx], (HeapWord*)&_in[idx+1], ((_cnt-idx-1)*sizeof(Node*)));
874 }
875 _in[idx] = n; // Stuff over old required edge
876 if (n != NULL) n->add_out((Node *)this); // Add reciprocal def-use edge
877 Compile::current()->record_modified_node(this);
878 }
879
880 //-----------------------------find_edge---------------------------------------
881 int Node::find_edge(Node* n) {
882 for (uint i = 0; i < len(); i++) {
883 if (_in[i] == n) return i;
884 }
885 return -1;
886 }
887
888 //----------------------------replace_edge-------------------------------------
889 int Node::replace_edge(Node* old, Node* neww, PhaseGVN* gvn) {
890 if (old == neww) return 0; // nothing to do
891 uint nrep = 0;
892 for (uint i = 0; i < len(); i++) {
893 if (in(i) == old) {
894 if (i < req()) {
895 if (gvn != NULL) {
896 set_req_X(i, neww, gvn);
897 } else {
898 set_req(i, neww);
899 }
900 } else {
901 assert(gvn == NULL || gvn->is_IterGVN() == NULL, "no support for igvn here");
902 assert(find_prec_edge(neww) == -1, "spec violation: duplicated prec edge (node %d -> %d)", _idx, neww->_idx);
903 set_prec(i, neww);
904 }
905 nrep++;
906 }
907 }
908 return nrep;
909 }
910
911 /**
912 * Replace input edges in the range pointing to 'old' node.
913 */
914 int Node::replace_edges_in_range(Node* old, Node* neww, int start, int end, PhaseGVN* gvn) {
915 if (old == neww) return 0; // nothing to do
916 uint nrep = 0;
917 for (int i = start; i < end; i++) {
918 if (in(i) == old) {
919 set_req_X(i, neww, gvn);
920 nrep++;
921 }
922 }
923 return nrep;
924 }
925
926 //-------------------------disconnect_inputs-----------------------------------
927 // NULL out all inputs to eliminate incoming Def-Use edges.
928 void Node::disconnect_inputs(Compile* C) {
929 // the layout of Node::_in
930 // r: a required input, null is allowed
931 // p: a precedence, null values are all at the end
932 // -----------------------------------
933 // |r|...|r|p|...|p|null|...|null|
934 // | |
935 // req() len()
936 // -----------------------------------
937 for (uint i = 0; i < req(); ++i) {
938 if (in(i) != nullptr) {
939 set_req(i, nullptr);
940 }
941 }
942
943 // Remove precedence edges if any exist
944 // Note: Safepoints may have precedence edges, even during parsing
945 for (uint i = len(); i > req(); ) {
946 rm_prec(--i); // no-op if _in[i] is nullptr
947 }
948
949 #ifdef ASSERT
950 // sanity check
951 for (uint i = 0; i < len(); ++i) {
952 assert(_in[i] == nullptr, "disconnect_inputs() failed!");
953 }
954 #endif
955
956 // Node::destruct requires all out edges be deleted first
957 // debug_only(destruct();) // no reuse benefit expected
958 C->record_dead_node(_idx);
959 }
960
961 //-----------------------------uncast---------------------------------------
962 // %%% Temporary, until we sort out CheckCastPP vs. CastPP.
963 // Strip away casting. (It is depth-limited.)
964 // Optionally, keep casts with dependencies.
965 Node* Node::uncast(bool keep_deps) const {
966 // Should be inline:
967 //return is_ConstraintCast() ? uncast_helper(this) : (Node*) this;
968 if (is_ConstraintCast()) {
969 return uncast_helper(this, keep_deps);
970 } else {
971 return (Node*) this;
972 }
973 }
974
975 // Find out of current node that matches opcode.
976 Node* Node::find_out_with(int opcode) {
977 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
978 Node* use = fast_out(i);
979 if (use->Opcode() == opcode) {
980 return use;
981 }
982 }
983 return NULL;
984 }
985
986 // Return true if the current node has an out that matches opcode.
987 bool Node::has_out_with(int opcode) {
988 return (find_out_with(opcode) != NULL);
989 }
990
991 // Return true if the current node has an out that matches any of the opcodes.
992 bool Node::has_out_with(int opcode1, int opcode2, int opcode3, int opcode4) {
993 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
994 int opcode = fast_out(i)->Opcode();
995 if (opcode == opcode1 || opcode == opcode2 || opcode == opcode3 || opcode == opcode4) {
996 return true;
997 }
998 }
999 return false;
1000 }
1001
1002
1003 //---------------------------uncast_helper-------------------------------------
1004 Node* Node::uncast_helper(const Node* p, bool keep_deps) {
1005 #ifdef ASSERT
1006 uint depth_count = 0;
1007 const Node* orig_p = p;
1008 #endif
1009
1010 while (true) {
1011 #ifdef ASSERT
1012 if (depth_count >= K) {
1013 orig_p->dump(4);
1014 if (p != orig_p)
1015 p->dump(1);
1016 }
1017 assert(depth_count++ < K, "infinite loop in Node::uncast_helper");
1018 #endif
1019 if (p == NULL || p->req() != 2) {
1020 break;
1021 } else if (p->is_ConstraintCast()) {
1022 if (keep_deps && p->as_ConstraintCast()->carry_dependency()) {
1023 break; // stop at casts with dependencies
1024 }
1025 p = p->in(1);
1026 } else {
1027 break;
1028 }
1029 }
1030 return (Node*) p;
1031 }
1032
1033 //------------------------------add_prec---------------------------------------
1034 // Add a new precedence input. Precedence inputs are unordered, with
1035 // duplicates removed and NULLs packed down at the end.
1036 void Node::add_prec( Node *n ) {
1037 assert( is_not_dead(n), "can not use dead node");
1038
1039 // Check for NULL at end
1040 if( _cnt >= _max || in(_max-1) )
1041 grow( _max+1 );
1042
1043 // Find a precedence edge to move
1044 uint i = _cnt;
1045 while( in(i) != NULL ) {
1046 if (in(i) == n) return; // Avoid spec violation: duplicated prec edge.
1047 i++;
1048 }
1049 _in[i] = n; // Stuff prec edge over NULL
1050 if ( n != NULL) n->add_out((Node *)this); // Add mirror edge
1051
1052 #ifdef ASSERT
1053 while ((++i)<_max) { assert(_in[i] == NULL, "spec violation: Gap in prec edges (node %d)", _idx); }
1054 #endif
1055 Compile::current()->record_modified_node(this);
1056 }
1057
1058 //------------------------------rm_prec----------------------------------------
1059 // Remove a precedence input. Precedence inputs are unordered, with
1060 // duplicates removed and NULLs packed down at the end.
1061 void Node::rm_prec( uint j ) {
1062 assert(j < _max, "oob: i=%d, _max=%d", j, _max);
1063 assert(j >= _cnt, "not a precedence edge");
1064 if (_in[j] == NULL) return; // Avoid spec violation: Gap in prec edges.
1065 _in[j]->del_out((Node *)this);
1066 close_prec_gap_at(j);
1067 Compile::current()->record_modified_node(this);
1068 }
1069
1070 //------------------------------size_of----------------------------------------
1071 uint Node::size_of() const { return sizeof(*this); }
1072
1073 //------------------------------ideal_reg--------------------------------------
1074 uint Node::ideal_reg() const { return 0; }
1075
1076 //------------------------------jvms-------------------------------------------
1077 JVMState* Node::jvms() const { return NULL; }
1078
1079 #ifdef ASSERT
1080 //------------------------------jvms-------------------------------------------
1081 bool Node::verify_jvms(const JVMState* using_jvms) const {
1082 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
1083 if (jvms == using_jvms) return true;
1084 }
1085 return false;
1086 }
1087
1088 //------------------------------init_NodeProperty------------------------------
1089 void Node::init_NodeProperty() {
1090 assert(_max_classes <= max_juint, "too many NodeProperty classes");
1091 assert(max_flags() <= max_juint, "too many NodeProperty flags");
1092 }
1093
1094 //-----------------------------max_flags---------------------------------------
1095 juint Node::max_flags() {
1096 return (PD::_last_flag << 1) - 1; // allow flags combination
1097 }
1098 #endif
1099
1100 //------------------------------format-----------------------------------------
1101 // Print as assembly
1102 void Node::format( PhaseRegAlloc *, outputStream *st ) const {}
1103 //------------------------------emit-------------------------------------------
1104 // Emit bytes starting at parameter 'ptr'.
1105 void Node::emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const {}
1106 //------------------------------size-------------------------------------------
1107 // Size of instruction in bytes
1108 uint Node::size(PhaseRegAlloc *ra_) const { return 0; }
1109
1110 //------------------------------CFG Construction-------------------------------
1111 // Nodes that end basic blocks, e.g. IfTrue/IfFalse, JumpProjNode, Root,
1112 // Goto and Return.
1113 const Node *Node::is_block_proj() const { return 0; }
1114
1115 // Minimum guaranteed type
1116 const Type *Node::bottom_type() const { return Type::BOTTOM; }
1117
1118
1119 //------------------------------raise_bottom_type------------------------------
1120 // Get the worst-case Type output for this Node.
1121 void Node::raise_bottom_type(const Type* new_type) {
1122 if (is_Type()) {
1123 TypeNode *n = this->as_Type();
1124 if (VerifyAliases) {
1125 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1126 }
1127 n->set_type(new_type);
1128 } else if (is_Load()) {
1129 LoadNode *n = this->as_Load();
1130 if (VerifyAliases) {
1131 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1132 }
1133 n->set_type(new_type);
1134 }
1135 }
1136
1137 //------------------------------Identity---------------------------------------
1138 // Return a node that the given node is equivalent to.
1139 Node* Node::Identity(PhaseGVN* phase) {
1140 return this; // Default to no identities
1141 }
1142
1143 //------------------------------Value------------------------------------------
1144 // Compute a new Type for a node using the Type of the inputs.
1145 const Type* Node::Value(PhaseGVN* phase) const {
1146 return bottom_type(); // Default to worst-case Type
1147 }
1148
1149 //------------------------------Ideal------------------------------------------
1150 //
1151 // 'Idealize' the graph rooted at this Node.
1152 //
1153 // In order to be efficient and flexible there are some subtle invariants
1154 // these Ideal calls need to hold. Running with '+VerifyIterativeGVN' checks
1155 // these invariants, although its too slow to have on by default. If you are
1156 // hacking an Ideal call, be sure to test with +VerifyIterativeGVN!
1157 //
1158 // The Ideal call almost arbitrarily reshape the graph rooted at the 'this'
1159 // pointer. If ANY change is made, it must return the root of the reshaped
1160 // graph - even if the root is the same Node. Example: swapping the inputs
1161 // to an AddINode gives the same answer and same root, but you still have to
1162 // return the 'this' pointer instead of NULL.
1163 //
1164 // You cannot return an OLD Node, except for the 'this' pointer. Use the
1165 // Identity call to return an old Node; basically if Identity can find
1166 // another Node have the Ideal call make no change and return NULL.
1167 // Example: AddINode::Ideal must check for add of zero; in this case it
1168 // returns NULL instead of doing any graph reshaping.
1169 //
1170 // You cannot modify any old Nodes except for the 'this' pointer. Due to
1171 // sharing there may be other users of the old Nodes relying on their current
1172 // semantics. Modifying them will break the other users.
1173 // Example: when reshape "(X+3)+4" into "X+7" you must leave the Node for
1174 // "X+3" unchanged in case it is shared.
1175 //
1176 // If you modify the 'this' pointer's inputs, you should use
1177 // 'set_req'. If you are making a new Node (either as the new root or
1178 // some new internal piece) you may use 'init_req' to set the initial
1179 // value. You can make a new Node with either 'new' or 'clone'. In
1180 // either case, def-use info is correctly maintained.
1181 //
1182 // Example: reshape "(X+3)+4" into "X+7":
1183 // set_req(1, in(1)->in(1));
1184 // set_req(2, phase->intcon(7));
1185 // return this;
1186 // Example: reshape "X*4" into "X<<2"
1187 // return new LShiftINode(in(1), phase->intcon(2));
1188 //
1189 // You must call 'phase->transform(X)' on any new Nodes X you make, except
1190 // for the returned root node. Example: reshape "X*31" with "(X<<5)-X".
1191 // Node *shift=phase->transform(new LShiftINode(in(1),phase->intcon(5)));
1192 // return new AddINode(shift, in(1));
1193 //
1194 // When making a Node for a constant use 'phase->makecon' or 'phase->intcon'.
1195 // These forms are faster than 'phase->transform(new ConNode())' and Do
1196 // The Right Thing with def-use info.
1197 //
1198 // You cannot bury the 'this' Node inside of a graph reshape. If the reshaped
1199 // graph uses the 'this' Node it must be the root. If you want a Node with
1200 // the same Opcode as the 'this' pointer use 'clone'.
1201 //
1202 Node *Node::Ideal(PhaseGVN *phase, bool can_reshape) {
1203 return NULL; // Default to being Ideal already
1204 }
1205
1206 // Some nodes have specific Ideal subgraph transformations only if they are
1207 // unique users of specific nodes. Such nodes should be put on IGVN worklist
1208 // for the transformations to happen.
1209 bool Node::has_special_unique_user() const {
1210 assert(outcnt() == 1, "match only for unique out");
1211 Node* n = unique_out();
1212 int op = Opcode();
1213 if (this->is_Store()) {
1214 // Condition for back-to-back stores folding.
1215 return n->Opcode() == op && n->in(MemNode::Memory) == this;
1216 } else if (this->is_Load() || this->is_DecodeN() || this->is_Phi()) {
1217 // Condition for removing an unused LoadNode or DecodeNNode from the MemBarAcquire precedence input
1218 return n->Opcode() == Op_MemBarAcquire;
1219 } else if (op == Op_AddL) {
1220 // Condition for convL2I(addL(x,y)) ==> addI(convL2I(x),convL2I(y))
1221 return n->Opcode() == Op_ConvL2I && n->in(1) == this;
1222 } else if (op == Op_SubI || op == Op_SubL) {
1223 // Condition for subI(x,subI(y,z)) ==> subI(addI(x,z),y)
1224 return n->Opcode() == op && n->in(2) == this;
1225 } else if (is_If() && (n->is_IfFalse() || n->is_IfTrue())) {
1226 // See IfProjNode::Identity()
1227 return true;
1228 } else if ((is_IfFalse() || is_IfTrue()) && n->is_If()) {
1229 // See IfNode::fold_compares
1230 return true;
1231 } else {
1232 return false;
1233 }
1234 };
1235
1236 //--------------------------find_exact_control---------------------------------
1237 // Skip Proj and CatchProj nodes chains. Check for Null and Top.
1238 Node* Node::find_exact_control(Node* ctrl) {
1239 if (ctrl == NULL && this->is_Region())
1240 ctrl = this->as_Region()->is_copy();
1241
1242 if (ctrl != NULL && ctrl->is_CatchProj()) {
1243 if (ctrl->as_CatchProj()->_con == CatchProjNode::fall_through_index)
1244 ctrl = ctrl->in(0);
1245 if (ctrl != NULL && !ctrl->is_top())
1246 ctrl = ctrl->in(0);
1247 }
1248
1249 if (ctrl != NULL && ctrl->is_Proj())
1250 ctrl = ctrl->in(0);
1251
1252 return ctrl;
1253 }
1254
1255 //--------------------------dominates------------------------------------------
1256 // Helper function for MemNode::all_controls_dominate().
1257 // Check if 'this' control node dominates or equal to 'sub' control node.
1258 // We already know that if any path back to Root or Start reaches 'this',
1259 // then all paths so, so this is a simple search for one example,
1260 // not an exhaustive search for a counterexample.
1261 bool Node::dominates(Node* sub, Node_List &nlist) {
1262 assert(this->is_CFG(), "expecting control");
1263 assert(sub != NULL && sub->is_CFG(), "expecting control");
1264
1265 // detect dead cycle without regions
1266 int iterations_without_region_limit = DominatorSearchLimit;
1267
1268 Node* orig_sub = sub;
1269 Node* dom = this;
1270 bool met_dom = false;
1271 nlist.clear();
1272
1273 // Walk 'sub' backward up the chain to 'dom', watching for regions.
1274 // After seeing 'dom', continue up to Root or Start.
1275 // If we hit a region (backward split point), it may be a loop head.
1276 // Keep going through one of the region's inputs. If we reach the
1277 // same region again, go through a different input. Eventually we
1278 // will either exit through the loop head, or give up.
1279 // (If we get confused, break out and return a conservative 'false'.)
1280 while (sub != NULL) {
1281 if (sub->is_top()) break; // Conservative answer for dead code.
1282 if (sub == dom) {
1283 if (nlist.size() == 0) {
1284 // No Region nodes except loops were visited before and the EntryControl
1285 // path was taken for loops: it did not walk in a cycle.
1286 return true;
1287 } else if (met_dom) {
1288 break; // already met before: walk in a cycle
1289 } else {
1290 // Region nodes were visited. Continue walk up to Start or Root
1291 // to make sure that it did not walk in a cycle.
1292 met_dom = true; // first time meet
1293 iterations_without_region_limit = DominatorSearchLimit; // Reset
1294 }
1295 }
1296 if (sub->is_Start() || sub->is_Root()) {
1297 // Success if we met 'dom' along a path to Start or Root.
1298 // We assume there are no alternative paths that avoid 'dom'.
1299 // (This assumption is up to the caller to ensure!)
1300 return met_dom;
1301 }
1302 Node* up = sub->in(0);
1303 // Normalize simple pass-through regions and projections:
1304 up = sub->find_exact_control(up);
1305 // If sub == up, we found a self-loop. Try to push past it.
1306 if (sub == up && sub->is_Loop()) {
1307 // Take loop entry path on the way up to 'dom'.
1308 up = sub->in(1); // in(LoopNode::EntryControl);
1309 } else if (sub == up && sub->is_Region() && sub->req() == 2) {
1310 // Take in(1) path on the way up to 'dom' for regions with only one input
1311 up = sub->in(1);
1312 } else if (sub == up && sub->is_Region() && sub->req() == 3) {
1313 // Try both paths for Regions with 2 input paths (it may be a loop head).
1314 // It could give conservative 'false' answer without information
1315 // which region's input is the entry path.
1316 iterations_without_region_limit = DominatorSearchLimit; // Reset
1317
1318 bool region_was_visited_before = false;
1319 // Was this Region node visited before?
1320 // If so, we have reached it because we accidentally took a
1321 // loop-back edge from 'sub' back into the body of the loop,
1322 // and worked our way up again to the loop header 'sub'.
1323 // So, take the first unexplored path on the way up to 'dom'.
1324 for (int j = nlist.size() - 1; j >= 0; j--) {
1325 intptr_t ni = (intptr_t)nlist.at(j);
1326 Node* visited = (Node*)(ni & ~1);
1327 bool visited_twice_already = ((ni & 1) != 0);
1328 if (visited == sub) {
1329 if (visited_twice_already) {
1330 // Visited 2 paths, but still stuck in loop body. Give up.
1331 return false;
1332 }
1333 // The Region node was visited before only once.
1334 // (We will repush with the low bit set, below.)
1335 nlist.remove(j);
1336 // We will find a new edge and re-insert.
1337 region_was_visited_before = true;
1338 break;
1339 }
1340 }
1341
1342 // Find an incoming edge which has not been seen yet; walk through it.
1343 assert(up == sub, "");
1344 uint skip = region_was_visited_before ? 1 : 0;
1345 for (uint i = 1; i < sub->req(); i++) {
1346 Node* in = sub->in(i);
1347 if (in != NULL && !in->is_top() && in != sub) {
1348 if (skip == 0) {
1349 up = in;
1350 break;
1351 }
1352 --skip; // skip this nontrivial input
1353 }
1354 }
1355
1356 // Set 0 bit to indicate that both paths were taken.
1357 nlist.push((Node*)((intptr_t)sub + (region_was_visited_before ? 1 : 0)));
1358 }
1359
1360 if (up == sub) {
1361 break; // some kind of tight cycle
1362 }
1363 if (up == orig_sub && met_dom) {
1364 // returned back after visiting 'dom'
1365 break; // some kind of cycle
1366 }
1367 if (--iterations_without_region_limit < 0) {
1368 break; // dead cycle
1369 }
1370 sub = up;
1371 }
1372
1373 // Did not meet Root or Start node in pred. chain.
1374 // Conservative answer for dead code.
1375 return false;
1376 }
1377
1378 //------------------------------remove_dead_region-----------------------------
1379 // This control node is dead. Follow the subgraph below it making everything
1380 // using it dead as well. This will happen normally via the usual IterGVN
1381 // worklist but this call is more efficient. Do not update use-def info
1382 // inside the dead region, just at the borders.
1383 static void kill_dead_code( Node *dead, PhaseIterGVN *igvn ) {
1384 // Con's are a popular node to re-hit in the hash table again.
1385 if( dead->is_Con() ) return;
1386
1387 ResourceMark rm;
1388 Node_List nstack;
1389
1390 Node *top = igvn->C->top();
1391 nstack.push(dead);
1392 bool has_irreducible_loop = igvn->C->has_irreducible_loop();
1393
1394 while (nstack.size() > 0) {
1395 dead = nstack.pop();
1396 if (dead->Opcode() == Op_SafePoint) {
1397 dead->as_SafePoint()->disconnect_from_root(igvn);
1398 }
1399 if (dead->outcnt() > 0) {
1400 // Keep dead node on stack until all uses are processed.
1401 nstack.push(dead);
1402 // For all Users of the Dead... ;-)
1403 for (DUIterator_Last kmin, k = dead->last_outs(kmin); k >= kmin; ) {
1404 Node* use = dead->last_out(k);
1405 igvn->hash_delete(use); // Yank from hash table prior to mod
1406 if (use->in(0) == dead) { // Found another dead node
1407 assert (!use->is_Con(), "Control for Con node should be Root node.");
1408 use->set_req(0, top); // Cut dead edge to prevent processing
1409 nstack.push(use); // the dead node again.
1410 } else if (!has_irreducible_loop && // Backedge could be alive in irreducible loop
1411 use->is_Loop() && !use->is_Root() && // Don't kill Root (RootNode extends LoopNode)
1412 use->in(LoopNode::EntryControl) == dead) { // Dead loop if its entry is dead
1413 use->set_req(LoopNode::EntryControl, top); // Cut dead edge to prevent processing
1414 use->set_req(0, top); // Cut self edge
1415 nstack.push(use);
1416 } else { // Else found a not-dead user
1417 // Dead if all inputs are top or null
1418 bool dead_use = !use->is_Root(); // Keep empty graph alive
1419 for (uint j = 1; j < use->req(); j++) {
1420 Node* in = use->in(j);
1421 if (in == dead) { // Turn all dead inputs into TOP
1422 use->set_req(j, top);
1423 } else if (in != NULL && !in->is_top()) {
1424 dead_use = false;
1425 }
1426 }
1427 if (dead_use) {
1428 if (use->is_Region()) {
1429 use->set_req(0, top); // Cut self edge
1430 }
1431 nstack.push(use);
1432 } else {
1433 igvn->_worklist.push(use);
1434 }
1435 }
1436 // Refresh the iterator, since any number of kills might have happened.
1437 k = dead->last_outs(kmin);
1438 }
1439 } else { // (dead->outcnt() == 0)
1440 // Done with outputs.
1441 igvn->hash_delete(dead);
1442 igvn->_worklist.remove(dead);
1443 igvn->set_type(dead, Type::TOP);
1444 // Kill all inputs to the dead guy
1445 for (uint i=0; i < dead->req(); i++) {
1446 Node *n = dead->in(i); // Get input to dead guy
1447 if (n != NULL && !n->is_top()) { // Input is valid?
1448 dead->set_req(i, top); // Smash input away
1449 if (n->outcnt() == 0) { // Input also goes dead?
1450 if (!n->is_Con())
1451 nstack.push(n); // Clear it out as well
1452 } else if (n->outcnt() == 1 &&
1453 n->has_special_unique_user()) {
1454 igvn->add_users_to_worklist( n );
1455 } else if (n->outcnt() <= 2 && n->is_Store()) {
1456 // Push store's uses on worklist to enable folding optimization for
1457 // store/store and store/load to the same address.
1458 // The restriction (outcnt() <= 2) is the same as in set_req_X()
1459 // and remove_globally_dead_node().
1460 igvn->add_users_to_worklist( n );
1461 } else {
1462 BarrierSet::barrier_set()->barrier_set_c2()->enqueue_useful_gc_barrier(igvn, n);
1463 }
1464 }
1465 }
1466 igvn->C->remove_useless_node(dead);
1467 } // (dead->outcnt() == 0)
1468 } // while (nstack.size() > 0) for outputs
1469 return;
1470 }
1471
1472 //------------------------------remove_dead_region-----------------------------
1473 bool Node::remove_dead_region(PhaseGVN *phase, bool can_reshape) {
1474 Node *n = in(0);
1475 if( !n ) return false;
1476 // Lost control into this guy? I.e., it became unreachable?
1477 // Aggressively kill all unreachable code.
1478 if (can_reshape && n->is_top()) {
1479 kill_dead_code(this, phase->is_IterGVN());
1480 return false; // Node is dead.
1481 }
1482
1483 if( n->is_Region() && n->as_Region()->is_copy() ) {
1484 Node *m = n->nonnull_req();
1485 set_req(0, m);
1486 return true;
1487 }
1488 return false;
1489 }
1490
1491 //------------------------------hash-------------------------------------------
1492 // Hash function over Nodes.
1493 uint Node::hash() const {
1494 uint sum = 0;
1495 for( uint i=0; i<_cnt; i++ ) // Add in all inputs
1496 sum = (sum<<1)-(uintptr_t)in(i); // Ignore embedded NULLs
1497 return (sum>>2) + _cnt + Opcode();
1498 }
1499
1500 //------------------------------cmp--------------------------------------------
1501 // Compare special parts of simple Nodes
1502 bool Node::cmp( const Node &n ) const {
1503 return true; // Must be same
1504 }
1505
1506 //------------------------------rematerialize-----------------------------------
1507 // Should we clone rather than spill this instruction?
1508 bool Node::rematerialize() const {
1509 if ( is_Mach() )
1510 return this->as_Mach()->rematerialize();
1511 else
1512 return (_flags & Flag_rematerialize) != 0;
1513 }
1514
1515 //------------------------------needs_anti_dependence_check---------------------
1516 // Nodes which use memory without consuming it, hence need antidependences.
1517 bool Node::needs_anti_dependence_check() const {
1518 if (req() < 2 || (_flags & Flag_needs_anti_dependence_check) == 0) {
1519 return false;
1520 }
1521 return in(1)->bottom_type()->has_memory();
1522 }
1523
1524 // Get an integer constant from a ConNode (or CastIINode).
1525 // Return a default value if there is no apparent constant here.
1526 const TypeInt* Node::find_int_type() const {
1527 if (this->is_Type()) {
1528 return this->as_Type()->type()->isa_int();
1529 } else if (this->is_Con()) {
1530 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1531 return this->bottom_type()->isa_int();
1532 }
1533 return NULL;
1534 }
1535
1536 const TypeInteger* Node::find_integer_type(BasicType bt) const {
1537 if (this->is_Type()) {
1538 return this->as_Type()->type()->isa_integer(bt);
1539 } else if (this->is_Con()) {
1540 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1541 return this->bottom_type()->isa_integer(bt);
1542 }
1543 return NULL;
1544 }
1545
1546 // Get a pointer constant from a ConstNode.
1547 // Returns the constant if it is a pointer ConstNode
1548 intptr_t Node::get_ptr() const {
1549 assert( Opcode() == Op_ConP, "" );
1550 return ((ConPNode*)this)->type()->is_ptr()->get_con();
1551 }
1552
1553 // Get a narrow oop constant from a ConNNode.
1554 intptr_t Node::get_narrowcon() const {
1555 assert( Opcode() == Op_ConN, "" );
1556 return ((ConNNode*)this)->type()->is_narrowoop()->get_con();
1557 }
1558
1559 // Get a long constant from a ConNode.
1560 // Return a default value if there is no apparent constant here.
1561 const TypeLong* Node::find_long_type() const {
1562 if (this->is_Type()) {
1563 return this->as_Type()->type()->isa_long();
1564 } else if (this->is_Con()) {
1565 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1566 return this->bottom_type()->isa_long();
1567 }
1568 return NULL;
1569 }
1570
1571
1572 /**
1573 * Return a ptr type for nodes which should have it.
1574 */
1575 const TypePtr* Node::get_ptr_type() const {
1576 const TypePtr* tp = this->bottom_type()->make_ptr();
1577 #ifdef ASSERT
1578 if (tp == NULL) {
1579 this->dump(1);
1580 assert((tp != NULL), "unexpected node type");
1581 }
1582 #endif
1583 return tp;
1584 }
1585
1586 // Get a double constant from a ConstNode.
1587 // Returns the constant if it is a double ConstNode
1588 jdouble Node::getd() const {
1589 assert( Opcode() == Op_ConD, "" );
1590 return ((ConDNode*)this)->type()->is_double_constant()->getd();
1591 }
1592
1593 // Get a float constant from a ConstNode.
1594 // Returns the constant if it is a float ConstNode
1595 jfloat Node::getf() const {
1596 assert( Opcode() == Op_ConF, "" );
1597 return ((ConFNode*)this)->type()->is_float_constant()->getf();
1598 }
1599
1600 #ifndef PRODUCT
1601
1602 // Call this from debugger:
1603 Node* old_root() {
1604 Matcher* matcher = Compile::current()->matcher();
1605 if (matcher != nullptr) {
1606 Node* new_root = Compile::current()->root();
1607 Node* old_root = matcher->find_old_node(new_root);
1608 if (old_root != nullptr) {
1609 return old_root;
1610 }
1611 }
1612 tty->print("old_root: not found.\n");
1613 return nullptr;
1614 }
1615
1616 // BFS traverse all reachable nodes from start, call callback on them
1617 template <typename Callback>
1618 void visit_nodes(Node* start, Callback callback, bool traverse_output, bool only_ctrl) {
1619 Unique_Mixed_Node_List worklist;
1620 worklist.add(start);
1621 for (uint i = 0; i < worklist.size(); i++) {
1622 Node* n = worklist[i];
1623 callback(n);
1624 for (uint i = 0; i < n->len(); i++) {
1625 if (!only_ctrl || n->is_Region() || (n->Opcode() == Op_Root) || (i == TypeFunc::Control)) {
1626 // If only_ctrl is set: Add regions, the root node, or control inputs only
1627 worklist.add(n->in(i));
1628 }
1629 }
1630 if (traverse_output && !only_ctrl) {
1631 for (uint i = 0; i < n->outcnt(); i++) {
1632 worklist.add(n->raw_out(i));
1633 }
1634 }
1635 }
1636 }
1637
1638 // BFS traverse from start, return node with idx
1639 Node* find_node_by_idx(Node* start, uint idx, bool traverse_output, bool only_ctrl) {
1640 ResourceMark rm;
1641 Node* result = nullptr;
1642 auto callback = [&] (Node* n) {
1643 if (n->_idx == idx) {
1644 if (result != nullptr) {
1645 tty->print("find_node_by_idx: " INTPTR_FORMAT " and " INTPTR_FORMAT " both have idx==%d\n",
1646 (uintptr_t)result, (uintptr_t)n, idx);
1647 }
1648 result = n;
1649 }
1650 };
1651 visit_nodes(start, callback, traverse_output, only_ctrl);
1652 return result;
1653 }
1654
1655 int node_idx_cmp(const Node** n1, const Node** n2) {
1656 return (*n1)->_idx - (*n2)->_idx;
1657 }
1658
1659 void find_nodes_by_name(Node* start, const char* name) {
1660 ResourceMark rm;
1661 GrowableArray<const Node*> ns;
1662 auto callback = [&] (const Node* n) {
1663 if (StringUtils::is_star_match(name, n->Name())) {
1664 ns.push(n);
1665 }
1666 };
1667 visit_nodes(start, callback, true, false);
1668 ns.sort(node_idx_cmp);
1669 for (int i = 0; i < ns.length(); i++) {
1670 ns.at(i)->dump();
1671 }
1672 }
1673
1674 void find_nodes_by_dump(Node* start, const char* pattern) {
1675 ResourceMark rm;
1676 GrowableArray<const Node*> ns;
1677 auto callback = [&] (const Node* n) {
1678 stringStream stream;
1679 n->dump("", false, &stream);
1680 if (StringUtils::is_star_match(pattern, stream.base())) {
1681 ns.push(n);
1682 }
1683 };
1684 visit_nodes(start, callback, true, false);
1685 ns.sort(node_idx_cmp);
1686 for (int i = 0; i < ns.length(); i++) {
1687 ns.at(i)->dump();
1688 }
1689 }
1690
1691 // call from debugger: find node with name pattern in new/current graph
1692 // name can contain "*" in match pattern to match any characters
1693 // the matching is case insensitive
1694 void find_nodes_by_name(const char* name) {
1695 Node* root = Compile::current()->root();
1696 find_nodes_by_name(root, name);
1697 }
1698
1699 // call from debugger: find node with name pattern in old graph
1700 // name can contain "*" in match pattern to match any characters
1701 // the matching is case insensitive
1702 void find_old_nodes_by_name(const char* name) {
1703 Node* root = old_root();
1704 find_nodes_by_name(root, name);
1705 }
1706
1707 // call from debugger: find node with dump pattern in new/current graph
1708 // can contain "*" in match pattern to match any characters
1709 // the matching is case insensitive
1710 void find_nodes_by_dump(const char* pattern) {
1711 Node* root = Compile::current()->root();
1712 find_nodes_by_dump(root, pattern);
1713 }
1714
1715 // call from debugger: find node with name pattern in old graph
1716 // can contain "*" in match pattern to match any characters
1717 // the matching is case insensitive
1718 void find_old_nodes_by_dump(const char* pattern) {
1719 Node* root = old_root();
1720 find_nodes_by_dump(root, pattern);
1721 }
1722
1723 // Call this from debugger, search in same graph as n:
1724 Node* find_node(Node* n, const int idx) {
1725 return n->find(idx);
1726 }
1727
1728 // Call this from debugger, search in new nodes:
1729 Node* find_node(const int idx) {
1730 return Compile::current()->root()->find(idx);
1731 }
1732
1733 // Call this from debugger, search in old nodes:
1734 Node* find_old_node(const int idx) {
1735 Node* root = old_root();
1736 return (root == nullptr) ? nullptr : root->find(idx);
1737 }
1738
1739 // Call this from debugger, search in same graph as n:
1740 Node* find_ctrl(Node* n, const int idx) {
1741 return n->find_ctrl(idx);
1742 }
1743
1744 // Call this from debugger, search in new nodes:
1745 Node* find_ctrl(const int idx) {
1746 return Compile::current()->root()->find_ctrl(idx);
1747 }
1748
1749 // Call this from debugger, search in old nodes:
1750 Node* find_old_ctrl(const int idx) {
1751 Node* root = old_root();
1752 return (root == nullptr) ? nullptr : root->find_ctrl(idx);
1753 }
1754
1755 //------------------------------find_ctrl--------------------------------------
1756 // Find an ancestor to this node in the control history with given _idx
1757 Node* Node::find_ctrl(int idx) {
1758 return find(idx, true);
1759 }
1760
1761 //------------------------------find-------------------------------------------
1762 // Tries to find the node with the index |idx| starting from this node. If idx is negative,
1763 // the search also includes forward (out) edges. Returns NULL if not found.
1764 // If only_ctrl is set, the search will only be done on control nodes. Returns NULL if
1765 // not found or if the node to be found is not a control node (search will not find it).
1766 Node* Node::find(const int idx, bool only_ctrl) {
1767 ResourceMark rm;
1768 return find_node_by_idx(this, abs(idx), (idx < 0), only_ctrl);
1769 }
1770
1771 class PrintBFS {
1772 public:
1773 PrintBFS(const Node* start, const int max_distance, const Node* target, const char* options)
1774 : _start(start), _max_distance(max_distance), _target(target), _options(options),
1775 _dcc(this), _info_uid(cmpkey, hashkey) {}
1776
1777 void run();
1778 private:
1779 // pipeline steps
1780 bool configure();
1781 void collect();
1782 void select();
1783 void select_all();
1784 void select_all_paths();
1785 void select_shortest_path();
1786 void sort();
1787 void print();
1788
1789 // inputs
1790 const Node* _start;
1791 const int _max_distance;
1792 const Node* _target;
1793 const char* _options;
1794
1795 // options
1796 bool _traverse_inputs = false;
1797 bool _traverse_outputs = false;
1798 struct Filter {
1799 bool _control = false;
1800 bool _memory = false;
1801 bool _data = false;
1802 bool _mixed = false;
1803 bool _other = false;
1804 bool is_empty() const {
1805 return !(_control || _memory || _data || _mixed || _other);
1806 }
1807 void set_all() {
1808 _control = true;
1809 _memory = true;
1810 _data = true;
1811 _mixed = true;
1812 _other = true;
1813 }
1814 // Check if the filter accepts the node. Go by the type categories, but also all CFG nodes
1815 // are considered to have control.
1816 bool accepts(const Node* n) {
1817 const Type* t = n->bottom_type();
1818 return ( _data && t->has_category(Type::Category::Data) ) ||
1819 ( _memory && t->has_category(Type::Category::Memory) ) ||
1820 ( _mixed && t->has_category(Type::Category::Mixed) ) ||
1821 ( _control && (t->has_category(Type::Category::Control) || n->is_CFG()) ) ||
1822 ( _other && t->has_category(Type::Category::Other) );
1823 }
1824 };
1825 Filter _filter_visit;
1826 Filter _filter_boundary;
1827 bool _sort_idx = false;
1828 bool _all_paths = false;
1829 bool _use_color = false;
1830 bool _print_blocks = false;
1831 bool _print_old = false;
1832 bool _dump_only = false;
1833 static void print_options_help(bool print_examples);
1834 bool parse_options();
1835
1836 public:
1837 class DumpConfigColored : public Node::DumpConfig {
1838 public:
1839 DumpConfigColored(PrintBFS* bfs) : _bfs(bfs) {};
1840 virtual void pre_dump(outputStream* st, const Node* n);
1841 virtual void post_dump(outputStream* st);
1842 private:
1843 PrintBFS* _bfs;
1844 };
1845 private:
1846 DumpConfigColored _dcc;
1847
1848 // node info
1849 static Node* old_node(const Node* n); // mach node -> prior IR node
1850 static void print_node_idx(const Node* n); // to tty
1851 static void print_block_id(const Block* b); // to tty
1852 static void print_node_block(const Node* n); // to tty: _pre_order, head idx, _idom, _dom_depth
1853
1854 // traversal data structures
1855 GrowableArray<const Node*> _worklist; // BFS queue
1856 void maybe_traverse(const Node* src, const Node* dst);
1857
1858 // node info annotation
1859 class Info {
1860 public:
1861 Info() : Info(nullptr, 0) {};
1862 Info(const Node* node, int distance)
1863 : _node(node), _distance_from_start(distance) {};
1864 const Node* node() const { return _node; };
1865 int distance() const { return _distance_from_start; };
1866 int distance_from_target() const { return _distance_from_target; }
1867 void set_distance_from_target(int d) { _distance_from_target = d; }
1868 GrowableArray<const Node*> edge_bwd; // pointing toward _start
1869 bool is_marked() const { return _mark; } // marked to keep during select
1870 void set_mark() { _mark = true; }
1871 private:
1872 const Node* _node;
1873 int _distance_from_start; // distance from _start
1874 int _distance_from_target = 0; // distance from _target if _all_paths
1875 bool _mark = false;
1876 };
1877 Dict _info_uid; // Node -> uid
1878 GrowableArray<Info> _info; // uid -> info
1879
1880 Info* find_info(const Node* n) {
1881 size_t uid = (size_t)_info_uid[n];
1882 if (uid == 0) {
1883 return nullptr;
1884 }
1885 return &_info.at((int)uid);
1886 }
1887
1888 void make_info(const Node* node, const int distance) {
1889 assert(find_info(node) == nullptr, "node does not yet have info");
1890 size_t uid = _info.length() + 1;
1891 _info_uid.Insert((void*)node, (void*)uid);
1892 _info.at_put_grow((int)uid, Info(node, distance));
1893 assert(find_info(node)->node() == node, "stored correct node");
1894 };
1895
1896 // filled by sort, printed by print
1897 GrowableArray<const Node*> _print_list;
1898
1899 // print header + node table
1900 void print_header() const;
1901 void print_node(const Node* n);
1902 };
1903
1904 void PrintBFS::run() {
1905 if (!configure()) {
1906 return;
1907 }
1908 collect();
1909 select();
1910 sort();
1911 print();
1912 }
1913
1914 // set up configuration for BFS and print
1915 bool PrintBFS::configure() {
1916 if (_max_distance < 0) {
1917 tty->print("dump_bfs: max_distance must be non-negative!\n");
1918 return false;
1919 }
1920 return parse_options();
1921 }
1922
1923 // BFS traverse according to configuration, fill worklist and info
1924 void PrintBFS::collect() {
1925 maybe_traverse(_start, _start);
1926 int pos = 0;
1927 while (pos < _worklist.length()) {
1928 const Node* n = _worklist.at(pos++); // next node to traverse
1929 Info* info = find_info(n);
1930 if (!_filter_visit.accepts(n) && n != _start) {
1931 continue; // we hit boundary, do not traverse further
1932 }
1933 if (n != _start && n->is_Root()) {
1934 continue; // traversing through root node would lead to unrelated nodes
1935 }
1936 if (_traverse_inputs && _max_distance > info->distance()) {
1937 for (uint i = 0; i < n->req(); i++) {
1938 maybe_traverse(n, n->in(i));
1939 }
1940 }
1941 if (_traverse_outputs && _max_distance > info->distance()) {
1942 for (uint i = 0; i < n->outcnt(); i++) {
1943 maybe_traverse(n, n->raw_out(i));
1944 }
1945 }
1946 }
1947 }
1948
1949 // go through work list, mark those that we want to print
1950 void PrintBFS::select() {
1951 if (_target == nullptr ) {
1952 select_all();
1953 } else {
1954 if (find_info(_target) == nullptr) {
1955 tty->print("Could not find target in BFS.\n");
1956 return;
1957 }
1958 if (_all_paths) {
1959 select_all_paths();
1960 } else {
1961 select_shortest_path();
1962 }
1963 }
1964 }
1965
1966 // take all nodes from BFS
1967 void PrintBFS::select_all() {
1968 for (int i = 0; i < _worklist.length(); i++) {
1969 const Node* n = _worklist.at(i);
1970 Info* info = find_info(n);
1971 info->set_mark();
1972 }
1973 }
1974
1975 // traverse backward from target, along edges found in BFS
1976 void PrintBFS::select_all_paths() {
1977 int pos = 0;
1978 GrowableArray<const Node*> backtrace;
1979 // start from target
1980 backtrace.push(_target);
1981 find_info(_target)->set_mark();
1982 // traverse backward
1983 while (pos < backtrace.length()) {
1984 const Node* n = backtrace.at(pos++);
1985 Info* info = find_info(n);
1986 for (int i = 0; i < info->edge_bwd.length(); i++) {
1987 // all backward edges
1988 const Node* back = info->edge_bwd.at(i);
1989 Info* back_info = find_info(back);
1990 if (!back_info->is_marked()) {
1991 // not yet found this on way back.
1992 back_info->set_distance_from_target(info->distance_from_target() + 1);
1993 if (back_info->distance_from_target() + back_info->distance() <= _max_distance) {
1994 // total distance is small enough
1995 back_info->set_mark();
1996 backtrace.push(back);
1997 }
1998 }
1999 }
2000 }
2001 }
2002
2003 void PrintBFS::select_shortest_path() {
2004 const Node* current = _target;
2005 while (true) {
2006 Info* info = find_info(current);
2007 info->set_mark();
2008 if (current == _start) {
2009 break;
2010 }
2011 // first edge -> leads us one step closer to _start
2012 current = info->edge_bwd.at(0);
2013 }
2014 }
2015
2016 // go through worklist in desired order, put the marked ones in print list
2017 void PrintBFS::sort() {
2018 if (_traverse_inputs && !_traverse_outputs) {
2019 // reverse order
2020 for (int i = _worklist.length() - 1; i >= 0; i--) {
2021 const Node* n = _worklist.at(i);
2022 Info* info = find_info(n);
2023 if (info->is_marked()) {
2024 _print_list.push(n);
2025 }
2026 }
2027 } else {
2028 // same order as worklist
2029 for (int i = 0; i < _worklist.length(); i++) {
2030 const Node* n = _worklist.at(i);
2031 Info* info = find_info(n);
2032 if (info->is_marked()) {
2033 _print_list.push(n);
2034 }
2035 }
2036 }
2037 if (_sort_idx) {
2038 _print_list.sort(node_idx_cmp);
2039 }
2040 }
2041
2042 // go through printlist and print
2043 void PrintBFS::print() {
2044 if (_print_list.length() > 0 ) {
2045 print_header();
2046 for (int i = 0; i < _print_list.length(); i++) {
2047 const Node* n = _print_list.at(i);
2048 print_node(n);
2049 }
2050 } else {
2051 tty->print("No nodes to print.\n");
2052 }
2053 }
2054
2055 void PrintBFS::print_options_help(bool print_examples) {
2056 tty->print("Usage: node->dump_bfs(int max_distance, Node* target, char* options)\n");
2057 tty->print("\n");
2058 tty->print("Use cases:\n");
2059 tty->print(" BFS traversal: no target required\n");
2060 tty->print(" shortest path: set target\n");
2061 tty->print(" all paths: set target and put 'A' in options\n");
2062 tty->print(" detect loop: subcase of all paths, have start==target\n");
2063 tty->print("\n");
2064 tty->print("Arguments:\n");
2065 tty->print(" this/start: staring point of BFS\n");
2066 tty->print(" target:\n");
2067 tty->print(" if nullptr: simple BFS\n");
2068 tty->print(" else: shortest path or all paths between this/start and target\n");
2069 tty->print(" options:\n");
2070 tty->print(" if nullptr: same as \"cdmox@B\"\n");
2071 tty->print(" else: use combination of following characters\n");
2072 tty->print(" h: display this help info\n");
2073 tty->print(" H: display this help info, with examples\n");
2074 tty->print(" +: traverse in-edges (on if neither + nor -)\n");
2075 tty->print(" -: traverse out-edges\n");
2076 tty->print(" c: visit control nodes\n");
2077 tty->print(" d: visit data nodes\n");
2078 tty->print(" m: visit memory nodes\n");
2079 tty->print(" o: visit other nodes\n");
2080 tty->print(" x: visit mixed nodes\n");
2081 tty->print(" C: boundary control nodes\n");
2082 tty->print(" D: boundary data nodes\n");
2083 tty->print(" M: boundary memory nodes\n");
2084 tty->print(" O: boundary other nodes\n");
2085 tty->print(" X: boundary mixed nodes\n");
2086 tty->print(" #: display node category in color (not supported in all terminals)\n");
2087 tty->print(" S: sort displayed nodes by node idx\n");
2088 tty->print(" A: all paths (not just shortest path to target)\n");
2089 tty->print(" @: print old nodes - before matching (if available)\n");
2090 tty->print(" B: print scheduling blocks (if available)\n");
2091 tty->print(" $: dump only, no header, no other columns\n");
2092 tty->print("\n");
2093 tty->print("recursively follow edges to nodes with permitted visit types,\n");
2094 tty->print("on the boundary additionally display nodes allowed in boundary types\n");
2095 tty->print("Note: the categories can be overlapping. For example a mixed node\n");
2096 tty->print(" can contain control and memory output. Some from the other\n");
2097 tty->print(" category are also control (Halt, Return, etc).\n");
2098 tty->print("\n");
2099 tty->print("output columns:\n");
2100 tty->print(" dist: BFS distance to this/start\n");
2101 tty->print(" apd: all paths distance (d_start + d_target)\n");
2102 tty->print(" block: block identifier, based on _pre_order\n");
2103 tty->print(" head: first node in block\n");
2104 tty->print(" idom: head node of idom block\n");
2105 tty->print(" depth: depth of block (_dom_depth)\n");
2106 tty->print(" old: old IR node - before matching\n");
2107 tty->print(" dump: node->dump()\n");
2108 tty->print("\n");
2109 tty->print("Note: if none of the \"cmdxo\" characters are in the options string\n");
2110 tty->print(" then we set all of them.\n");
2111 tty->print(" This allows for short strings like \"#\" for colored input traversal\n");
2112 tty->print(" or \"-#\" for colored output traversal.\n");
2113 if (print_examples) {
2114 tty->print("\n");
2115 tty->print("Examples:\n");
2116 tty->print(" if->dump_bfs(10, 0, \"+cxo\")\n");
2117 tty->print(" starting at some if node, traverse inputs recursively\n");
2118 tty->print(" only along control (mixed and other can also be control)\n");
2119 tty->print(" phi->dump_bfs(5, 0, \"-dxo\")\n");
2120 tty->print(" starting at phi node, traverse outputs recursively\n");
2121 tty->print(" only along data (mixed and other can also have data flow)\n");
2122 tty->print(" find_node(385)->dump_bfs(3, 0, \"cdmox+#@B\")\n");
2123 tty->print(" find inputs of node 385, up to 3 nodes up (+)\n");
2124 tty->print(" traverse all nodes (cdmox), use colors (#)\n");
2125 tty->print(" display old nodes and blocks, if they exist\n");
2126 tty->print(" useful call to start with\n");
2127 tty->print(" find_node(102)->dump_bfs(10, 0, \"dCDMOX-\")\n");
2128 tty->print(" find non-data dependencies of a data node\n");
2129 tty->print(" follow data node outputs until we find another category\n");
2130 tty->print(" node as the boundary\n");
2131 tty->print(" x->dump_bfs(10, y, 0)\n");
2132 tty->print(" find shortest path from x to y, along any edge or node\n");
2133 tty->print(" will not find a path if it is longer than 10\n");
2134 tty->print(" useful to find how x and y are related\n");
2135 tty->print(" find_node(741)->dump_bfs(20, find_node(746), \"c+\")\n");
2136 tty->print(" find shortest control path between two nodes\n");
2137 tty->print(" find_node(741)->dump_bfs(8, find_node(746), \"cdmox+A\")\n");
2138 tty->print(" find all paths (A) between two nodes of length at most 8\n");
2139 tty->print(" find_node(741)->dump_bfs(7, find_node(741), \"c+A\")\n");
2140 tty->print(" find all control loops for this node\n");
2141 }
2142 }
2143
2144 bool PrintBFS::parse_options() {
2145 if (_options == nullptr) {
2146 _options = "cdmox@B"; // default options
2147 }
2148 size_t len = strlen(_options);
2149 for (size_t i = 0; i < len; i++) {
2150 switch (_options[i]) {
2151 case '+':
2152 _traverse_inputs = true;
2153 break;
2154 case '-':
2155 _traverse_outputs = true;
2156 break;
2157 case 'c':
2158 _filter_visit._control = true;
2159 break;
2160 case 'm':
2161 _filter_visit._memory = true;
2162 break;
2163 case 'd':
2164 _filter_visit._data = true;
2165 break;
2166 case 'x':
2167 _filter_visit._mixed = true;
2168 break;
2169 case 'o':
2170 _filter_visit._other = true;
2171 break;
2172 case 'C':
2173 _filter_boundary._control = true;
2174 break;
2175 case 'M':
2176 _filter_boundary._memory = true;
2177 break;
2178 case 'D':
2179 _filter_boundary._data = true;
2180 break;
2181 case 'X':
2182 _filter_boundary._mixed = true;
2183 break;
2184 case 'O':
2185 _filter_boundary._other = true;
2186 break;
2187 case 'S':
2188 _sort_idx = true;
2189 break;
2190 case 'A':
2191 _all_paths = true;
2192 break;
2193 case '#':
2194 _use_color = true;
2195 break;
2196 case 'B':
2197 _print_blocks = true;
2198 break;
2199 case '@':
2200 _print_old = true;
2201 break;
2202 case '$':
2203 _dump_only = true;
2204 break;
2205 case 'h':
2206 print_options_help(false);
2207 return false;
2208 case 'H':
2209 print_options_help(true);
2210 return false;
2211 default:
2212 tty->print_cr("dump_bfs: Unrecognized option \'%c\'", _options[i]);
2213 tty->print_cr("for help, run: find_node(0)->dump_bfs(0,0,\"H\")");
2214 return false;
2215 }
2216 }
2217 if (!_traverse_inputs && !_traverse_outputs) {
2218 _traverse_inputs = true;
2219 }
2220 if (_filter_visit.is_empty()) {
2221 _filter_visit.set_all();
2222 }
2223 Compile* C = Compile::current();
2224 _print_old &= (C->matcher() != nullptr); // only show old if there are new
2225 _print_blocks &= (C->cfg() != nullptr); // only show blocks if available
2226 return true;
2227 }
2228
2229 void PrintBFS::DumpConfigColored::pre_dump(outputStream* st, const Node* n) {
2230 if (!_bfs->_use_color) {
2231 return;
2232 }
2233 Info* info = _bfs->find_info(n);
2234 if (info == nullptr || !info->is_marked()) {
2235 return;
2236 }
2237
2238 const Type* t = n->bottom_type();
2239 switch (t->category()) {
2240 case Type::Category::Data:
2241 st->print("\u001b[34m");
2242 break;
2243 case Type::Category::Memory:
2244 st->print("\u001b[32m");
2245 break;
2246 case Type::Category::Mixed:
2247 st->print("\u001b[35m");
2248 break;
2249 case Type::Category::Control:
2250 st->print("\u001b[31m");
2251 break;
2252 case Type::Category::Other:
2253 st->print("\u001b[33m");
2254 break;
2255 case Type::Category::Undef:
2256 n->dump();
2257 assert(false, "category undef ??");
2258 break;
2259 default:
2260 n->dump();
2261 assert(false, "not covered");
2262 break;
2263 }
2264 }
2265
2266 void PrintBFS::DumpConfigColored::post_dump(outputStream* st) {
2267 if (!_bfs->_use_color) {
2268 return;
2269 }
2270 st->print("\u001b[0m"); // white
2271 }
2272
2273 Node* PrintBFS::old_node(const Node* n) {
2274 Compile* C = Compile::current();
2275 if (C->matcher() == nullptr || !C->node_arena()->contains(n)) {
2276 return (Node*)nullptr;
2277 } else {
2278 return C->matcher()->find_old_node(n);
2279 }
2280 }
2281
2282 void PrintBFS::print_node_idx(const Node* n) {
2283 Compile* C = Compile::current();
2284 char buf[30];
2285 if (n == nullptr) {
2286 sprintf(buf,"_"); // null
2287 } else if (C->node_arena()->contains(n)) {
2288 sprintf(buf, "%d", n->_idx); // new node
2289 } else {
2290 sprintf(buf, "o%d", n->_idx); // old node
2291 }
2292 tty->print("%6s", buf);
2293 }
2294
2295 void PrintBFS::print_block_id(const Block* b) {
2296 Compile* C = Compile::current();
2297 char buf[30];
2298 sprintf(buf, "B%d", b->_pre_order);
2299 tty->print("%7s", buf);
2300 }
2301
2302 void PrintBFS::print_node_block(const Node* n) {
2303 Compile* C = Compile::current();
2304 Block* b = C->node_arena()->contains(n)
2305 ? C->cfg()->get_block_for_node(n)
2306 : nullptr; // guard against old nodes
2307 if (b == nullptr) {
2308 tty->print(" _"); // Block
2309 tty->print(" _"); // head
2310 tty->print(" _"); // idom
2311 tty->print(" _"); // depth
2312 } else {
2313 print_block_id(b);
2314 print_node_idx(b->head());
2315 if (b->_idom) {
2316 print_node_idx(b->_idom->head());
2317 } else {
2318 tty->print(" _"); // idom
2319 }
2320 tty->print("%6d ", b->_dom_depth);
2321 }
2322 }
2323
2324 // filter, and add to worklist, add info, note traversal edges
2325 void PrintBFS::maybe_traverse(const Node* src, const Node* dst) {
2326 if (dst != nullptr &&
2327 (_filter_visit.accepts(dst) ||
2328 _filter_boundary.accepts(dst) ||
2329 dst == _start)) { // correct category or start?
2330 if (find_info(dst) == nullptr) {
2331 // never visited - set up info
2332 _worklist.push(dst);
2333 int d = 0;
2334 if (dst != _start) {
2335 d = find_info(src)->distance() + 1;
2336 }
2337 make_info(dst, d);
2338 }
2339 if (src != dst) {
2340 // traversal edges useful during select
2341 find_info(dst)->edge_bwd.push(src);
2342 }
2343 }
2344 }
2345
2346 void PrintBFS::print_header() const {
2347 if (_dump_only) {
2348 return; // no header in dump only mode
2349 }
2350 tty->print("dist"); // distance
2351 if (_all_paths) {
2352 tty->print(" apd"); // all paths distance
2353 }
2354 if (_print_blocks) {
2355 tty->print(" [block head idom depth]"); // block
2356 }
2357 if (_print_old) {
2358 tty->print(" old"); // old node
2359 }
2360 tty->print(" dump\n"); // node dump
2361 tty->print("---------------------------------------------\n");
2362 }
2363
2364 void PrintBFS::print_node(const Node* n) {
2365 if (_dump_only) {
2366 n->dump("\n", false, tty, &_dcc);
2367 return;
2368 }
2369 tty->print("%4d", find_info(n)->distance());// distance
2370 if (_all_paths) {
2371 Info* info = find_info(n);
2372 int apd = info->distance() + info->distance_from_target();
2373 tty->print("%4d", apd); // all paths distance
2374 }
2375 if (_print_blocks) {
2376 print_node_block(n); // block
2377 }
2378 if (_print_old) {
2379 print_node_idx(old_node(n)); // old node
2380 }
2381 tty->print(" ");
2382 n->dump("\n", false, tty, &_dcc); // node dump
2383 }
2384
2385 //------------------------------dump_bfs--------------------------------------
2386 // Call this from debugger
2387 // Useful for BFS traversal, shortest path, all path, loop detection, etc
2388 // Designed to be more readable, and provide additional info
2389 // To find all options, run:
2390 // find_node(0)->dump_bfs(0,0,"H")
2391 void Node::dump_bfs(const int max_distance, Node* target, const char* options) const {
2392 PrintBFS bfs(this, max_distance, target, options);
2393 bfs.run();
2394 }
2395
2396 // Call this from debugger, with default arguments
2397 void Node::dump_bfs(const int max_distance) const {
2398 dump_bfs(max_distance, nullptr, nullptr);
2399 }
2400
2401 // -----------------------------dump_idx---------------------------------------
2402 void Node::dump_idx(bool align, outputStream* st, DumpConfig* dc) const {
2403 if (dc != nullptr) {
2404 dc->pre_dump(st, this);
2405 }
2406 Compile* C = Compile::current();
2407 bool is_new = C->node_arena()->contains(this);
2408 if (align) { // print prefix empty spaces$
2409 // +1 for leading digit, +1 for "o"
2410 uint max_width = static_cast<uint>(log10(static_cast<double>(C->unique()))) + 2;
2411 // +1 for leading digit, maybe +1 for "o"
2412 uint width = static_cast<uint>(log10(static_cast<double>(_idx))) + 1 + (is_new ? 0 : 1);
2413 while (max_width > width) {
2414 st->print(" ");
2415 width++;
2416 }
2417 }
2418 if (!is_new) {
2419 st->print("o");
2420 }
2421 st->print("%d", _idx);
2422 if (dc != nullptr) {
2423 dc->post_dump(st);
2424 }
2425 }
2426
2427 // -----------------------------dump_name--------------------------------------
2428 void Node::dump_name(outputStream* st, DumpConfig* dc) const {
2429 if (dc != nullptr) {
2430 dc->pre_dump(st, this);
2431 }
2432 st->print("%s", Name());
2433 if (dc != nullptr) {
2434 dc->post_dump(st);
2435 }
2436 }
2437
2438 // -----------------------------Name-------------------------------------------
2439 extern const char *NodeClassNames[];
2440 const char *Node::Name() const { return NodeClassNames[Opcode()]; }
2441
2442 static bool is_disconnected(const Node* n) {
2443 for (uint i = 0; i < n->req(); i++) {
2444 if (n->in(i) != NULL) return false;
2445 }
2446 return true;
2447 }
2448
2449 #ifdef ASSERT
2450 void Node::dump_orig(outputStream *st, bool print_key) const {
2451 Compile* C = Compile::current();
2452 Node* orig = _debug_orig;
2453 if (not_a_node(orig)) orig = NULL;
2454 if (orig != NULL && !C->node_arena()->contains(orig)) orig = NULL;
2455 if (orig == NULL) return;
2456 if (print_key) {
2457 st->print(" !orig=");
2458 }
2459 Node* fast = orig->debug_orig(); // tortoise & hare algorithm to detect loops
2460 if (not_a_node(fast)) fast = NULL;
2461 while (orig != NULL) {
2462 bool discon = is_disconnected(orig); // if discon, print [123] else 123
2463 if (discon) st->print("[");
2464 if (!Compile::current()->node_arena()->contains(orig))
2465 st->print("o");
2466 st->print("%d", orig->_idx);
2467 if (discon) st->print("]");
2468 orig = orig->debug_orig();
2469 if (not_a_node(orig)) orig = NULL;
2470 if (orig != NULL && !C->node_arena()->contains(orig)) orig = NULL;
2471 if (orig != NULL) st->print(",");
2472 if (fast != NULL) {
2473 // Step fast twice for each single step of orig:
2474 fast = fast->debug_orig();
2475 if (not_a_node(fast)) fast = NULL;
2476 if (fast != NULL && fast != orig) {
2477 fast = fast->debug_orig();
2478 if (not_a_node(fast)) fast = NULL;
2479 }
2480 if (fast == orig) {
2481 st->print("...");
2482 break;
2483 }
2484 }
2485 }
2486 }
2487
2488 void Node::set_debug_orig(Node* orig) {
2489 _debug_orig = orig;
2490 if (BreakAtNode == 0) return;
2491 if (not_a_node(orig)) orig = NULL;
2492 int trip = 10;
2493 while (orig != NULL) {
2494 if (orig->debug_idx() == BreakAtNode || (int)orig->_idx == BreakAtNode) {
2495 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=%d orig._idx=%d orig._debug_idx=%d",
2496 this->_idx, this->debug_idx(), orig->_idx, orig->debug_idx());
2497 BREAKPOINT;
2498 }
2499 orig = orig->debug_orig();
2500 if (not_a_node(orig)) orig = NULL;
2501 if (trip-- <= 0) break;
2502 }
2503 }
2504 #endif //ASSERT
2505
2506 //------------------------------dump------------------------------------------
2507 // Dump a Node
2508 void Node::dump(const char* suffix, bool mark, outputStream* st, DumpConfig* dc) const {
2509 Compile* C = Compile::current();
2510 bool is_new = C->node_arena()->contains(this);
2511 C->_in_dump_cnt++;
2512
2513 // idx mark name ===
2514 dump_idx(true, st, dc);
2515 st->print(mark ? " >" : " ");
2516 dump_name(st, dc);
2517 st->print(" === ");
2518
2519 // Dump the required and precedence inputs
2520 dump_req(st, dc);
2521 dump_prec(st, dc);
2522 // Dump the outputs
2523 dump_out(st, dc);
2524
2525 if (is_disconnected(this)) {
2526 #ifdef ASSERT
2527 st->print(" [%d]",debug_idx());
2528 dump_orig(st);
2529 #endif
2530 st->cr();
2531 C->_in_dump_cnt--;
2532 return; // don't process dead nodes
2533 }
2534
2535 if (C->clone_map().value(_idx) != 0) {
2536 C->clone_map().dump(_idx);
2537 }
2538 // Dump node-specific info
2539 dump_spec(st);
2540 #ifdef ASSERT
2541 // Dump the non-reset _debug_idx
2542 if (Verbose && WizardMode) {
2543 st->print(" [%d]",debug_idx());
2544 }
2545 #endif
2546
2547 const Type *t = bottom_type();
2548
2549 if (t != NULL && (t->isa_instptr() || t->isa_instklassptr())) {
2550 const TypeInstPtr *toop = t->isa_instptr();
2551 const TypeInstKlassPtr *tkls = t->isa_instklassptr();
2552 if (toop) {
2553 st->print(" Oop:");
2554 } else if (tkls) {
2555 st->print(" Klass:");
2556 }
2557 t->dump_on(st);
2558 } else if (t == Type::MEMORY) {
2559 st->print(" Memory:");
2560 MemNode::dump_adr_type(this, adr_type(), st);
2561 } else if (Verbose || WizardMode) {
2562 st->print(" Type:");
2563 if (t) {
2564 t->dump_on(st);
2565 } else {
2566 st->print("no type");
2567 }
2568 } else if (t->isa_vect() && this->is_MachSpillCopy()) {
2569 // Dump MachSpillcopy vector type.
2570 t->dump_on(st);
2571 }
2572 if (is_new) {
2573 DEBUG_ONLY(dump_orig(st));
2574 Node_Notes* nn = C->node_notes_at(_idx);
2575 if (nn != NULL && !nn->is_clear()) {
2576 if (nn->jvms() != NULL) {
2577 st->print(" !jvms:");
2578 nn->jvms()->dump_spec(st);
2579 }
2580 }
2581 }
2582 if (suffix) st->print("%s", suffix);
2583 C->_in_dump_cnt--;
2584 }
2585
2586 // call from debugger: dump node to tty with newline
2587 void Node::dump() const {
2588 dump("\n");
2589 }
2590
2591 //------------------------------dump_req--------------------------------------
2592 void Node::dump_req(outputStream* st, DumpConfig* dc) const {
2593 // Dump the required input edges
2594 for (uint i = 0; i < req(); i++) { // For all required inputs
2595 Node* d = in(i);
2596 if (d == NULL) {
2597 st->print("_ ");
2598 } else if (not_a_node(d)) {
2599 st->print("not_a_node "); // uninitialized, sentinel, garbage, etc.
2600 } else {
2601 d->dump_idx(false, st, dc);
2602 st->print(" ");
2603 }
2604 }
2605 }
2606
2607
2608 //------------------------------dump_prec-------------------------------------
2609 void Node::dump_prec(outputStream* st, DumpConfig* dc) const {
2610 // Dump the precedence edges
2611 int any_prec = 0;
2612 for (uint i = req(); i < len(); i++) { // For all precedence inputs
2613 Node* p = in(i);
2614 if (p != NULL) {
2615 if (!any_prec++) st->print(" |");
2616 if (not_a_node(p)) { st->print("not_a_node "); continue; }
2617 p->dump_idx(false, st, dc);
2618 st->print(" ");
2619 }
2620 }
2621 }
2622
2623 //------------------------------dump_out--------------------------------------
2624 void Node::dump_out(outputStream* st, DumpConfig* dc) const {
2625 // Delimit the output edges
2626 st->print(" [[ ");
2627 // Dump the output edges
2628 for (uint i = 0; i < _outcnt; i++) { // For all outputs
2629 Node* u = _out[i];
2630 if (u == NULL) {
2631 st->print("_ ");
2632 } else if (not_a_node(u)) {
2633 st->print("not_a_node ");
2634 } else {
2635 u->dump_idx(false, st, dc);
2636 st->print(" ");
2637 }
2638 }
2639 st->print("]] ");
2640 }
2641
2642 //------------------------------dump-------------------------------------------
2643 // call from debugger: dump Node's inputs (or outputs if d negative)
2644 void Node::dump(int d) const {
2645 dump_bfs(abs(d), nullptr, (d > 0) ? "+$" : "-$");
2646 }
2647
2648 //------------------------------dump_ctrl--------------------------------------
2649 // call from debugger: dump Node's control inputs (or outputs if d negative)
2650 void Node::dump_ctrl(int d) const {
2651 dump_bfs(abs(d), nullptr, (d > 0) ? "+$c" : "-$c");
2652 }
2653
2654 //-----------------------------dump_compact------------------------------------
2655 void Node::dump_comp() const {
2656 this->dump_comp("\n");
2657 }
2658
2659 //-----------------------------dump_compact------------------------------------
2660 // Dump a Node in compact representation, i.e., just print its name and index.
2661 // Nodes can specify additional specifics to print in compact representation by
2662 // implementing dump_compact_spec.
2663 void Node::dump_comp(const char* suffix, outputStream *st) const {
2664 Compile* C = Compile::current();
2665 C->_in_dump_cnt++;
2666 st->print("%s(%d)", Name(), _idx);
2667 this->dump_compact_spec(st);
2668 if (suffix) {
2669 st->print("%s", suffix);
2670 }
2671 C->_in_dump_cnt--;
2672 }
2673
2674 // VERIFICATION CODE
2675 // Verify all nodes if verify_depth is negative
2676 void Node::verify(int verify_depth, VectorSet& visited, Node_List& worklist) {
2677 assert(verify_depth != 0, "depth should not be 0");
2678 Compile* C = Compile::current();
2679 uint last_index_on_current_depth = worklist.size() - 1;
2680 verify_depth--; // Visiting the first node on depth 1
2681 // Only add nodes to worklist if verify_depth is negative (visit all nodes) or greater than 0
2682 bool add_to_worklist = verify_depth != 0;
2683
2684 for (uint list_index = 0; list_index < worklist.size(); list_index++) {
2685 Node* n = worklist[list_index];
2686
2687 if (n->is_Con() && n->bottom_type() == Type::TOP) {
2688 if (C->cached_top_node() == NULL) {
2689 C->set_cached_top_node((Node*)n);
2690 }
2691 assert(C->cached_top_node() == n, "TOP node must be unique");
2692 }
2693
2694 uint in_len = n->len();
2695 for (uint i = 0; i < in_len; i++) {
2696 Node* x = n->_in[i];
2697 if (!x || x->is_top()) {
2698 continue;
2699 }
2700
2701 // Verify my input has a def-use edge to me
2702 // Count use-def edges from n to x
2703 int cnt = 1;
2704 for (uint j = 0; j < i; j++) {
2705 if (n->_in[j] == x) {
2706 cnt++;
2707 break;
2708 }
2709 }
2710 if (cnt == 2) {
2711 // x is already checked as n's previous input, skip its duplicated def-use count checking
2712 continue;
2713 }
2714 for (uint j = i + 1; j < in_len; j++) {
2715 if (n->_in[j] == x) {
2716 cnt++;
2717 }
2718 }
2719
2720 // Count def-use edges from x to n
2721 uint max = x->_outcnt;
2722 for (uint k = 0; k < max; k++) {
2723 if (x->_out[k] == n) {
2724 cnt--;
2725 }
2726 }
2727 assert(cnt == 0, "mismatched def-use edge counts");
2728
2729 if (add_to_worklist && !visited.test_set(x->_idx)) {
2730 worklist.push(x);
2731 }
2732 }
2733
2734 if (verify_depth > 0 && list_index == last_index_on_current_depth) {
2735 // All nodes on this depth were processed and its inputs are on the worklist. Decrement verify_depth and
2736 // store the current last list index which is the last node in the list with the new depth. All nodes
2737 // added afterwards will have a new depth again. Stop adding new nodes if depth limit is reached (=0).
2738 verify_depth--;
2739 if (verify_depth == 0) {
2740 add_to_worklist = false;
2741 }
2742 last_index_on_current_depth = worklist.size() - 1;
2743 }
2744 }
2745 }
2746 #endif // not PRODUCT
2747
2748 //------------------------------Registers--------------------------------------
2749 // Do we Match on this edge index or not? Generally false for Control
2750 // and true for everything else. Weird for calls & returns.
2751 uint Node::match_edge(uint idx) const {
2752 return idx; // True for other than index 0 (control)
2753 }
2754
2755 // Register classes are defined for specific machines
2756 const RegMask &Node::out_RegMask() const {
2757 ShouldNotCallThis();
2758 return RegMask::Empty;
2759 }
2760
2761 const RegMask &Node::in_RegMask(uint) const {
2762 ShouldNotCallThis();
2763 return RegMask::Empty;
2764 }
2765
2766 void Node_Array::grow(uint i) {
2767 assert(_max > 0, "invariant");
2768 uint old = _max;
2769 _max = next_power_of_2(i);
2770 _nodes = (Node**)_a->Arealloc( _nodes, old*sizeof(Node*),_max*sizeof(Node*));
2771 Copy::zero_to_bytes( &_nodes[old], (_max-old)*sizeof(Node*) );
2772 }
2773
2774 void Node_Array::insert(uint i, Node* n) {
2775 if (_nodes[_max - 1]) {
2776 grow(_max);
2777 }
2778 Copy::conjoint_words_to_higher((HeapWord*)&_nodes[i], (HeapWord*)&_nodes[i + 1], ((_max - i - 1) * sizeof(Node*)));
2779 _nodes[i] = n;
2780 }
2781
2782 void Node_Array::remove(uint i) {
2783 Copy::conjoint_words_to_lower((HeapWord*)&_nodes[i + 1], (HeapWord*)&_nodes[i], ((_max - i - 1) * sizeof(Node*)));
2784 _nodes[_max - 1] = NULL;
2785 }
2786
2787 void Node_Array::dump() const {
2788 #ifndef PRODUCT
2789 for (uint i = 0; i < _max; i++) {
2790 Node* nn = _nodes[i];
2791 if (nn != NULL) {
2792 tty->print("%5d--> ",i); nn->dump();
2793 }
2794 }
2795 #endif
2796 }
2797
2798 //--------------------------is_iteratively_computed------------------------------
2799 // Operation appears to be iteratively computed (such as an induction variable)
2800 // It is possible for this operation to return false for a loop-varying
2801 // value, if it appears (by local graph inspection) to be computed by a simple conditional.
2802 bool Node::is_iteratively_computed() {
2803 if (ideal_reg()) { // does operation have a result register?
2804 for (uint i = 1; i < req(); i++) {
2805 Node* n = in(i);
2806 if (n != NULL && n->is_Phi()) {
2807 for (uint j = 1; j < n->req(); j++) {
2808 if (n->in(j) == this) {
2809 return true;
2810 }
2811 }
2812 }
2813 }
2814 }
2815 return false;
2816 }
2817
2818 //--------------------------find_similar------------------------------
2819 // Return a node with opcode "opc" and same inputs as "this" if one can
2820 // be found; Otherwise return NULL;
2821 Node* Node::find_similar(int opc) {
2822 if (req() >= 2) {
2823 Node* def = in(1);
2824 if (def && def->outcnt() >= 2) {
2825 for (DUIterator_Fast dmax, i = def->fast_outs(dmax); i < dmax; i++) {
2826 Node* use = def->fast_out(i);
2827 if (use != this &&
2828 use->Opcode() == opc &&
2829 use->req() == req()) {
2830 uint j;
2831 for (j = 0; j < use->req(); j++) {
2832 if (use->in(j) != in(j)) {
2833 break;
2834 }
2835 }
2836 if (j == use->req()) {
2837 return use;
2838 }
2839 }
2840 }
2841 }
2842 }
2843 return NULL;
2844 }
2845
2846
2847 //--------------------------unique_ctrl_out_or_null-------------------------
2848 // Return the unique control out if only one. Null if none or more than one.
2849 Node* Node::unique_ctrl_out_or_null() const {
2850 Node* found = NULL;
2851 for (uint i = 0; i < outcnt(); i++) {
2852 Node* use = raw_out(i);
2853 if (use->is_CFG() && use != this) {
2854 if (found != NULL) {
2855 return NULL;
2856 }
2857 found = use;
2858 }
2859 }
2860 return found;
2861 }
2862
2863 //--------------------------unique_ctrl_out------------------------------
2864 // Return the unique control out. Asserts if none or more than one control out.
2865 Node* Node::unique_ctrl_out() const {
2866 Node* ctrl = unique_ctrl_out_or_null();
2867 assert(ctrl != NULL, "control out is assumed to be unique");
2868 return ctrl;
2869 }
2870
2871 void Node::ensure_control_or_add_prec(Node* c) {
2872 if (in(0) == NULL) {
2873 set_req(0, c);
2874 } else if (in(0) != c) {
2875 add_prec(c);
2876 }
2877 }
2878
2879 bool Node::is_dead_loop_safe() const {
2880 if (is_Phi()) {
2881 return true;
2882 }
2883 if (is_Proj() && in(0) == NULL) {
2884 return true;
2885 }
2886 if ((_flags & (Flag_is_dead_loop_safe | Flag_is_Con)) != 0) {
2887 if (!is_Proj()) {
2888 return true;
2889 }
2890 if (in(0)->is_Allocate()) {
2891 return false;
2892 }
2893 // MemNode::can_see_stored_value() peeks through the boxing call
2894 if (in(0)->is_CallStaticJava() && in(0)->as_CallStaticJava()->is_boxing_method()) {
2895 return false;
2896 }
2897 return true;
2898 }
2899 return false;
2900 }
2901
2902 //=============================================================================
2903 //------------------------------yank-------------------------------------------
2904 // Find and remove
2905 void Node_List::yank( Node *n ) {
2906 uint i;
2907 for (i = 0; i < _cnt; i++) {
2908 if (_nodes[i] == n) {
2909 break;
2910 }
2911 }
2912
2913 if (i < _cnt) {
2914 _nodes[i] = _nodes[--_cnt];
2915 }
2916 }
2917
2918 //------------------------------dump-------------------------------------------
2919 void Node_List::dump() const {
2920 #ifndef PRODUCT
2921 for (uint i = 0; i < _cnt; i++) {
2922 if (_nodes[i]) {
2923 tty->print("%5d--> ", i);
2924 _nodes[i]->dump();
2925 }
2926 }
2927 #endif
2928 }
2929
2930 void Node_List::dump_simple() const {
2931 #ifndef PRODUCT
2932 for (uint i = 0; i < _cnt; i++) {
2933 if( _nodes[i] ) {
2934 tty->print(" %d", _nodes[i]->_idx);
2935 } else {
2936 tty->print(" NULL");
2937 }
2938 }
2939 #endif
2940 }
2941
2942 //=============================================================================
2943 //------------------------------remove-----------------------------------------
2944 void Unique_Node_List::remove(Node* n) {
2945 if (_in_worklist.test(n->_idx)) {
2946 for (uint i = 0; i < size(); i++) {
2947 if (_nodes[i] == n) {
2948 map(i, Node_List::pop());
2949 _in_worklist.remove(n->_idx);
2950 return;
2951 }
2952 }
2953 ShouldNotReachHere();
2954 }
2955 }
2956
2957 //-----------------------remove_useless_nodes----------------------------------
2958 // Remove useless nodes from worklist
2959 void Unique_Node_List::remove_useless_nodes(VectorSet &useful) {
2960 for (uint i = 0; i < size(); ++i) {
2961 Node *n = at(i);
2962 assert( n != NULL, "Did not expect null entries in worklist");
2963 if (!useful.test(n->_idx)) {
2964 _in_worklist.remove(n->_idx);
2965 map(i, Node_List::pop());
2966 --i; // Visit popped node
2967 // If it was last entry, loop terminates since size() was also reduced
2968 }
2969 }
2970 }
2971
2972 //=============================================================================
2973 void Node_Stack::grow() {
2974 size_t old_top = pointer_delta(_inode_top,_inodes,sizeof(INode)); // save _top
2975 size_t old_max = pointer_delta(_inode_max,_inodes,sizeof(INode));
2976 size_t max = old_max << 1; // max * 2
2977 _inodes = REALLOC_ARENA_ARRAY(_a, INode, _inodes, old_max, max);
2978 _inode_max = _inodes + max;
2979 _inode_top = _inodes + old_top; // restore _top
2980 }
2981
2982 // Node_Stack is used to map nodes.
2983 Node* Node_Stack::find(uint idx) const {
2984 uint sz = size();
2985 for (uint i = 0; i < sz; i++) {
2986 if (idx == index_at(i)) {
2987 return node_at(i);
2988 }
2989 }
2990 return NULL;
2991 }
2992
2993 //=============================================================================
2994 uint TypeNode::size_of() const { return sizeof(*this); }
2995 #ifndef PRODUCT
2996 void TypeNode::dump_spec(outputStream *st) const {
2997 if (!Verbose && !WizardMode) {
2998 // standard dump does this in Verbose and WizardMode
2999 st->print(" #"); _type->dump_on(st);
3000 }
3001 }
3002
3003 void TypeNode::dump_compact_spec(outputStream *st) const {
3004 st->print("#");
3005 _type->dump_on(st);
3006 }
3007 #endif
3008 uint TypeNode::hash() const {
3009 return Node::hash() + _type->hash();
3010 }
3011 bool TypeNode::cmp(const Node& n) const {
3012 return !Type::cmp(_type, ((TypeNode&)n)._type);
3013 }
3014 const Type* TypeNode::bottom_type() const { return _type; }
3015 const Type* TypeNode::Value(PhaseGVN* phase) const { return _type; }
3016
3017 //------------------------------ideal_reg--------------------------------------
3018 uint TypeNode::ideal_reg() const {
3019 return _type->ideal_reg();
3020 }