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