1 /*
2 * Copyright (c) 1997, 2016, 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/castnode.hpp"
32 #include "opto/cfgnode.hpp"
33 #include "opto/connode.hpp"
34 #include "opto/loopnode.hpp"
35 #include "opto/machnode.hpp"
36 #include "opto/matcher.hpp"
37 #include "opto/node.hpp"
38 #include "opto/opcodes.hpp"
39 #include "opto/regmask.hpp"
40 #include "opto/rootnode.hpp"
41 #include "opto/type.hpp"
42 #include "utilities/copy.hpp"
43 #include "utilities/macros.hpp"
44
45 class RegMask;
46 // #include "phase.hpp"
47 class PhaseTransform;
48 class PhaseGVN;
49
50 // Arena we are currently building Nodes in
51 const uint Node::NotAMachineReg = 0xffff0000;
52
53 #ifndef PRODUCT
54 extern int nodes_created;
55 #endif
56 #ifdef __clang__
57 #pragma clang diagnostic push
58 #pragma GCC diagnostic ignored "-Wuninitialized"
59 #endif
60
61 #ifdef ASSERT
62
63 //-------------------------- construct_node------------------------------------
64 // Set a breakpoint here to identify where a particular node index is built.
65 void Node::verify_construction() {
66 _debug_orig = NULL;
67 int old_debug_idx = Compile::debug_idx();
68 int new_debug_idx = old_debug_idx+1;
69 if (new_debug_idx > 0) {
70 // Arrange that the lowest five decimal digits of _debug_idx
71 // will repeat those of _idx. In case this is somehow pathological,
72 // we continue to assign negative numbers (!) consecutively.
73 const int mod = 100000;
74 int bump = (int)(_idx - new_debug_idx) % mod;
75 if (bump < 0) bump += mod;
76 assert(bump >= 0 && bump < mod, "");
77 new_debug_idx += bump;
78 }
79 Compile::set_debug_idx(new_debug_idx);
80 set_debug_idx( new_debug_idx );
81 assert(Compile::current()->unique() < (INT_MAX - 1), "Node limit exceeded INT_MAX");
82 assert(Compile::current()->live_nodes() < Compile::current()->max_node_limit(), "Live Node limit exceeded limit");
83 if (BreakAtNode != 0 && (_debug_idx == BreakAtNode || (int)_idx == BreakAtNode)) {
84 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=%d", _idx, _debug_idx);
85 BREAKPOINT;
86 }
87 #if OPTO_DU_ITERATOR_ASSERT
88 _last_del = NULL;
89 _del_tick = 0;
90 #endif
91 _hash_lock = 0;
92 }
93
94
95 // #ifdef ASSERT ...
96
97 #if OPTO_DU_ITERATOR_ASSERT
98 void DUIterator_Common::sample(const Node* node) {
99 _vdui = VerifyDUIterators;
100 _node = node;
101 _outcnt = node->_outcnt;
102 _del_tick = node->_del_tick;
103 _last = NULL;
104 }
105
106 void DUIterator_Common::verify(const Node* node, bool at_end_ok) {
107 assert(_node == node, "consistent iterator source");
108 assert(_del_tick == node->_del_tick, "no unexpected deletions allowed");
109 }
110
111 void DUIterator_Common::verify_resync() {
112 // Ensure that the loop body has just deleted the last guy produced.
113 const Node* node = _node;
114 // Ensure that at least one copy of the last-seen edge was deleted.
115 // Note: It is OK to delete multiple copies of the last-seen edge.
116 // Unfortunately, we have no way to verify that all the deletions delete
117 // that same edge. On this point we must use the Honor System.
118 assert(node->_del_tick >= _del_tick+1, "must have deleted an edge");
119 assert(node->_last_del == _last, "must have deleted the edge just produced");
120 // We liked this deletion, so accept the resulting outcnt and tick.
121 _outcnt = node->_outcnt;
122 _del_tick = node->_del_tick;
123 }
124
125 void DUIterator_Common::reset(const DUIterator_Common& that) {
126 if (this == &that) return; // ignore assignment to self
127 if (!_vdui) {
128 // We need to initialize everything, overwriting garbage values.
129 _last = that._last;
130 _vdui = that._vdui;
131 }
132 // Note: It is legal (though odd) for an iterator over some node x
133 // to be reassigned to iterate over another node y. Some doubly-nested
134 // progress loops depend on being able to do this.
135 const Node* node = that._node;
136 // Re-initialize everything, except _last.
137 _node = node;
138 _outcnt = node->_outcnt;
139 _del_tick = node->_del_tick;
140 }
141
142 void DUIterator::sample(const Node* node) {
143 DUIterator_Common::sample(node); // Initialize the assertion data.
144 _refresh_tick = 0; // No refreshes have happened, as yet.
145 }
146
147 void DUIterator::verify(const Node* node, bool at_end_ok) {
148 DUIterator_Common::verify(node, at_end_ok);
149 assert(_idx < node->_outcnt + (uint)at_end_ok, "idx in range");
150 }
151
152 void DUIterator::verify_increment() {
153 if (_refresh_tick & 1) {
154 // We have refreshed the index during this loop.
155 // Fix up _idx to meet asserts.
156 if (_idx > _outcnt) _idx = _outcnt;
157 }
158 verify(_node, true);
159 }
160
161 void DUIterator::verify_resync() {
162 // Note: We do not assert on _outcnt, because insertions are OK here.
163 DUIterator_Common::verify_resync();
164 // Make sure we are still in sync, possibly with no more out-edges:
165 verify(_node, true);
166 }
167
168 void DUIterator::reset(const DUIterator& that) {
169 if (this == &that) return; // self assignment is always a no-op
170 assert(that._refresh_tick == 0, "assign only the result of Node::outs()");
171 assert(that._idx == 0, "assign only the result of Node::outs()");
172 assert(_idx == that._idx, "already assigned _idx");
173 if (!_vdui) {
174 // We need to initialize everything, overwriting garbage values.
175 sample(that._node);
176 } else {
177 DUIterator_Common::reset(that);
178 if (_refresh_tick & 1) {
179 _refresh_tick++; // Clear the "was refreshed" flag.
180 }
181 assert(_refresh_tick < 2*100000, "DU iteration must converge quickly");
182 }
183 }
184
185 void DUIterator::refresh() {
186 DUIterator_Common::sample(_node); // Re-fetch assertion data.
187 _refresh_tick |= 1; // Set the "was refreshed" flag.
188 }
189
190 void DUIterator::verify_finish() {
191 // If the loop has killed the node, do not require it to re-run.
192 if (_node->_outcnt == 0) _refresh_tick &= ~1;
193 // If this assert triggers, it means that a loop used refresh_out_pos
194 // to re-synch an iteration index, but the loop did not correctly
195 // re-run itself, using a "while (progress)" construct.
196 // This iterator enforces the rule that you must keep trying the loop
197 // until it "runs clean" without any need for refreshing.
198 assert(!(_refresh_tick & 1), "the loop must run once with no refreshing");
199 }
200
201
202 void DUIterator_Fast::verify(const Node* node, bool at_end_ok) {
203 DUIterator_Common::verify(node, at_end_ok);
204 Node** out = node->_out;
205 uint cnt = node->_outcnt;
206 assert(cnt == _outcnt, "no insertions allowed");
207 assert(_outp >= out && _outp <= out + cnt - !at_end_ok, "outp in range");
208 // This last check is carefully designed to work for NO_OUT_ARRAY.
209 }
210
211 void DUIterator_Fast::verify_limit() {
212 const Node* node = _node;
213 verify(node, true);
214 assert(_outp == node->_out + node->_outcnt, "limit still correct");
215 }
216
217 void DUIterator_Fast::verify_resync() {
218 const Node* node = _node;
219 if (_outp == node->_out + _outcnt) {
220 // Note that the limit imax, not the pointer i, gets updated with the
221 // exact count of deletions. (For the pointer it's always "--i".)
222 assert(node->_outcnt+node->_del_tick == _outcnt+_del_tick, "no insertions allowed with deletion(s)");
223 // This is a limit pointer, with a name like "imax".
224 // Fudge the _last field so that the common assert will be happy.
225 _last = (Node*) node->_last_del;
226 DUIterator_Common::verify_resync();
227 } else {
228 assert(node->_outcnt < _outcnt, "no insertions allowed with deletion(s)");
229 // A normal internal pointer.
230 DUIterator_Common::verify_resync();
231 // Make sure we are still in sync, possibly with no more out-edges:
232 verify(node, true);
233 }
234 }
235
236 void DUIterator_Fast::verify_relimit(uint n) {
237 const Node* node = _node;
238 assert((int)n > 0, "use imax -= n only with a positive count");
239 // This must be a limit pointer, with a name like "imax".
240 assert(_outp == node->_out + node->_outcnt, "apply -= only to a limit (imax)");
241 // The reported number of deletions must match what the node saw.
242 assert(node->_del_tick == _del_tick + n, "must have deleted n edges");
243 // Fudge the _last field so that the common assert will be happy.
244 _last = (Node*) node->_last_del;
245 DUIterator_Common::verify_resync();
246 }
247
248 void DUIterator_Fast::reset(const DUIterator_Fast& that) {
249 assert(_outp == that._outp, "already assigned _outp");
250 DUIterator_Common::reset(that);
251 }
252
253 void DUIterator_Last::verify(const Node* node, bool at_end_ok) {
254 // at_end_ok means the _outp is allowed to underflow by 1
255 _outp += at_end_ok;
256 DUIterator_Fast::verify(node, at_end_ok); // check _del_tick, etc.
257 _outp -= at_end_ok;
258 assert(_outp == (node->_out + node->_outcnt) - 1, "pointer must point to end of nodes");
259 }
260
261 void DUIterator_Last::verify_limit() {
262 // Do not require the limit address to be resynched.
263 //verify(node, true);
264 assert(_outp == _node->_out, "limit still correct");
265 }
266
267 void DUIterator_Last::verify_step(uint num_edges) {
268 assert((int)num_edges > 0, "need non-zero edge count for loop progress");
269 _outcnt -= num_edges;
270 _del_tick += num_edges;
271 // Make sure we are still in sync, possibly with no more out-edges:
272 const Node* node = _node;
273 verify(node, true);
274 assert(node->_last_del == _last, "must have deleted the edge just produced");
275 }
276
277 #endif //OPTO_DU_ITERATOR_ASSERT
278
279
280 #endif //ASSERT
281
282
283 // This constant used to initialize _out may be any non-null value.
284 // The value NULL is reserved for the top node only.
285 #define NO_OUT_ARRAY ((Node**)-1)
286
287 // Out-of-line code from node constructors.
288 // Executed only when extra debug info. is being passed around.
289 static void init_node_notes(Compile* C, int idx, Node_Notes* nn) {
290 C->set_node_notes_at(idx, nn);
291 }
292
293 // Shared initialization code.
294 inline int Node::Init(int req) {
295 Compile* C = Compile::current();
296 int idx = C->next_unique();
297
298 // Allocate memory for the necessary number of edges.
299 if (req > 0) {
300 // Allocate space for _in array to have double alignment.
301 _in = (Node **) ((char *) (C->node_arena()->Amalloc_D(req * sizeof(void*))));
302 }
303 // If there are default notes floating around, capture them:
304 Node_Notes* nn = C->default_node_notes();
305 if (nn != NULL) init_node_notes(C, idx, nn);
306
307 // Note: At this point, C is dead,
308 // and we begin to initialize the new Node.
309
310 _cnt = _max = req;
311 _outcnt = _outmax = 0;
312 _class_id = Class_Node;
313 _flags = 0;
314 _out = NO_OUT_ARRAY;
315 return idx;
316 }
317
318 //------------------------------Node-------------------------------------------
319 // Create a Node, with a given number of required edges.
320 Node::Node(uint req)
321 : _idx(Init(req))
322 #ifdef ASSERT
323 , _parse_idx(_idx)
324 #endif
325 {
326 assert( req < Compile::current()->max_node_limit() - NodeLimitFudgeFactor, "Input limit exceeded" );
327 debug_only( verify_construction() );
328 NOT_PRODUCT(nodes_created++);
329 if (req == 0) {
330 _in = NULL;
331 } else {
332 Node** to = _in;
333 for(uint i = 0; i < req; i++) {
334 to[i] = NULL;
335 }
336 }
337 }
338
339 //------------------------------Node-------------------------------------------
340 Node::Node(Node *n0)
341 : _idx(Init(1))
342 #ifdef ASSERT
343 , _parse_idx(_idx)
344 #endif
345 {
346 debug_only( verify_construction() );
347 NOT_PRODUCT(nodes_created++);
348 assert( is_not_dead(n0), "can not use dead node");
349 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
350 }
351
352 //------------------------------Node-------------------------------------------
353 Node::Node(Node *n0, Node *n1)
354 : _idx(Init(2))
355 #ifdef ASSERT
356 , _parse_idx(_idx)
357 #endif
358 {
359 debug_only( verify_construction() );
360 NOT_PRODUCT(nodes_created++);
361 assert( is_not_dead(n0), "can not use dead node");
362 assert( is_not_dead(n1), "can not use dead node");
363 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
364 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
365 }
366
367 //------------------------------Node-------------------------------------------
368 Node::Node(Node *n0, Node *n1, Node *n2)
369 : _idx(Init(3))
370 #ifdef ASSERT
371 , _parse_idx(_idx)
372 #endif
373 {
374 debug_only( verify_construction() );
375 NOT_PRODUCT(nodes_created++);
376 assert( is_not_dead(n0), "can not use dead node");
377 assert( is_not_dead(n1), "can not use dead node");
378 assert( is_not_dead(n2), "can not use dead node");
379 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
380 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
381 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
382 }
383
384 //------------------------------Node-------------------------------------------
385 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3)
386 : _idx(Init(4))
387 #ifdef ASSERT
388 , _parse_idx(_idx)
389 #endif
390 {
391 debug_only( verify_construction() );
392 NOT_PRODUCT(nodes_created++);
393 assert( is_not_dead(n0), "can not use dead node");
394 assert( is_not_dead(n1), "can not use dead node");
395 assert( is_not_dead(n2), "can not use dead node");
396 assert( is_not_dead(n3), "can not use dead node");
397 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
398 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
399 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
400 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
401 }
402
403 //------------------------------Node-------------------------------------------
404 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3, Node *n4)
405 : _idx(Init(5))
406 #ifdef ASSERT
407 , _parse_idx(_idx)
408 #endif
409 {
410 debug_only( verify_construction() );
411 NOT_PRODUCT(nodes_created++);
412 assert( is_not_dead(n0), "can not use dead node");
413 assert( is_not_dead(n1), "can not use dead node");
414 assert( is_not_dead(n2), "can not use dead node");
415 assert( is_not_dead(n3), "can not use dead node");
416 assert( is_not_dead(n4), "can not use dead node");
417 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
418 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
419 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
420 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
421 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this);
422 }
423
424 //------------------------------Node-------------------------------------------
425 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3,
426 Node *n4, Node *n5)
427 : _idx(Init(6))
428 #ifdef ASSERT
429 , _parse_idx(_idx)
430 #endif
431 {
432 debug_only( verify_construction() );
433 NOT_PRODUCT(nodes_created++);
434 assert( is_not_dead(n0), "can not use dead node");
435 assert( is_not_dead(n1), "can not use dead node");
436 assert( is_not_dead(n2), "can not use dead node");
437 assert( is_not_dead(n3), "can not use dead node");
438 assert( is_not_dead(n4), "can not use dead node");
439 assert( is_not_dead(n5), "can not use dead node");
440 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
441 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
442 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
443 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
444 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this);
445 _in[5] = n5; if (n5 != NULL) n5->add_out((Node *)this);
446 }
447
448 //------------------------------Node-------------------------------------------
449 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3,
450 Node *n4, Node *n5, Node *n6)
451 : _idx(Init(7))
452 #ifdef ASSERT
453 , _parse_idx(_idx)
454 #endif
455 {
456 debug_only( verify_construction() );
457 NOT_PRODUCT(nodes_created++);
458 assert( is_not_dead(n0), "can not use dead node");
459 assert( is_not_dead(n1), "can not use dead node");
460 assert( is_not_dead(n2), "can not use dead node");
461 assert( is_not_dead(n3), "can not use dead node");
462 assert( is_not_dead(n4), "can not use dead node");
463 assert( is_not_dead(n5), "can not use dead node");
464 assert( is_not_dead(n6), "can not use dead node");
465 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
466 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
467 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
468 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
469 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this);
470 _in[5] = n5; if (n5 != NULL) n5->add_out((Node *)this);
471 _in[6] = n6; if (n6 != NULL) n6->add_out((Node *)this);
472 }
473
474 #ifdef __clang__
475 #pragma clang diagnostic pop
476 #endif
477
478
479 //------------------------------clone------------------------------------------
480 // Clone a Node.
481 Node *Node::clone() const {
482 Compile* C = Compile::current();
483 uint s = size_of(); // Size of inherited Node
484 Node *n = (Node*)C->node_arena()->Amalloc_D(size_of() + _max*sizeof(Node*));
485 Copy::conjoint_words_to_lower((HeapWord*)this, (HeapWord*)n, s);
486 // Set the new input pointer array
487 n->_in = (Node**)(((char*)n)+s);
488 // Cannot share the old output pointer array, so kill it
489 n->_out = NO_OUT_ARRAY;
490 // And reset the counters to 0
491 n->_outcnt = 0;
492 n->_outmax = 0;
493 // Unlock this guy, since he is not in any hash table.
494 debug_only(n->_hash_lock = 0);
495 // Walk the old node's input list to duplicate its edges
496 uint i;
497 for( i = 0; i < len(); i++ ) {
498 Node *x = in(i);
499 n->_in[i] = x;
500 if (x != NULL) x->add_out(n);
501 }
502 if (is_macro())
503 C->add_macro_node(n);
504 if (is_expensive())
505 C->add_expensive_node(n);
506 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
507 bs->register_potential_barrier_node(n);
508 // If the cloned node is a range check dependent CastII, add it to the list.
509 CastIINode* cast = n->isa_CastII();
510 if (cast != NULL && cast->has_range_check()) {
511 C->add_range_check_cast(cast);
512 }
513 if (n->Opcode() == Op_Opaque4) {
514 C->add_opaque4_node(n);
515 }
516
517 n->set_idx(C->next_unique()); // Get new unique index as well
518 debug_only( n->verify_construction() );
519 NOT_PRODUCT(nodes_created++);
520 // Do not patch over the debug_idx of a clone, because it makes it
521 // impossible to break on the clone's moment of creation.
522 //debug_only( n->set_debug_idx( debug_idx() ) );
523
524 C->copy_node_notes_to(n, (Node*) this);
525
526 // MachNode clone
527 uint nopnds;
528 if (this->is_Mach() && (nopnds = this->as_Mach()->num_opnds()) > 0) {
529 MachNode *mach = n->as_Mach();
530 MachNode *mthis = this->as_Mach();
531 // Get address of _opnd_array.
532 // It should be the same offset since it is the clone of this node.
533 MachOper **from = mthis->_opnds;
534 MachOper **to = (MachOper **)((size_t)(&mach->_opnds) +
535 pointer_delta((const void*)from,
536 (const void*)(&mthis->_opnds), 1));
537 mach->_opnds = to;
538 for ( uint i = 0; i < nopnds; ++i ) {
539 to[i] = from[i]->clone();
540 }
541 }
542 // cloning CallNode may need to clone JVMState
543 if (n->is_Call()) {
544 n->as_Call()->clone_jvms(C);
545 }
546 if (n->is_SafePoint()) {
547 n->as_SafePoint()->clone_replaced_nodes();
548 }
549 if (n->is_Load()) {
550 n->as_Load()->copy_barrier_info(this);
551 }
552 return n; // Return the clone
553 }
554
555 //---------------------------setup_is_top--------------------------------------
556 // Call this when changing the top node, to reassert the invariants
557 // required by Node::is_top. See Compile::set_cached_top_node.
558 void Node::setup_is_top() {
559 if (this == (Node*)Compile::current()->top()) {
560 // This node has just become top. Kill its out array.
561 _outcnt = _outmax = 0;
562 _out = NULL; // marker value for top
563 assert(is_top(), "must be top");
564 } else {
565 if (_out == NULL) _out = NO_OUT_ARRAY;
566 assert(!is_top(), "must not be top");
567 }
568 }
569
570 //------------------------------~Node------------------------------------------
571 // Fancy destructor; eagerly attempt to reclaim Node numberings and storage
572 void Node::destruct() {
573 // Eagerly reclaim unique Node numberings
574 Compile* compile = Compile::current();
575 if ((uint)_idx+1 == compile->unique()) {
576 compile->set_unique(compile->unique()-1);
577 }
578 // Clear debug info:
579 Node_Notes* nn = compile->node_notes_at(_idx);
580 if (nn != NULL) nn->clear();
581 // Walk the input array, freeing the corresponding output edges
582 _cnt = _max; // forget req/prec distinction
583 uint i;
584 for( i = 0; i < _max; i++ ) {
585 set_req(i, NULL);
586 //assert(def->out(def->outcnt()-1) == (Node *)this,"bad def-use hacking in reclaim");
587 }
588 assert(outcnt() == 0, "deleting a node must not leave a dangling use");
589 // See if the input array was allocated just prior to the object
590 int edge_size = _max*sizeof(void*);
591 int out_edge_size = _outmax*sizeof(void*);
592 char *edge_end = ((char*)_in) + edge_size;
593 char *out_array = (char*)(_out == NO_OUT_ARRAY? NULL: _out);
594 int node_size = size_of();
595
596 // Free the output edge array
597 if (out_edge_size > 0) {
598 compile->node_arena()->Afree(out_array, out_edge_size);
599 }
600
601 // Free the input edge array and the node itself
602 if( edge_end == (char*)this ) {
603 // It was; free the input array and object all in one hit
604 #ifndef ASSERT
605 compile->node_arena()->Afree(_in,edge_size+node_size);
606 #endif
607 } else {
608 // Free just the input array
609 compile->node_arena()->Afree(_in,edge_size);
610
611 // Free just the object
612 #ifndef ASSERT
613 compile->node_arena()->Afree(this,node_size);
614 #endif
615 }
616 if (is_macro()) {
617 compile->remove_macro_node(this);
618 }
619 if (is_expensive()) {
620 compile->remove_expensive_node(this);
621 }
622 CastIINode* cast = isa_CastII();
623 if (cast != NULL && cast->has_range_check()) {
624 compile->remove_range_check_cast(cast);
625 }
626 if (Opcode() == Op_Opaque4) {
627 compile->remove_opaque4_node(this);
628 }
629
630 if (is_SafePoint()) {
631 as_SafePoint()->delete_replaced_nodes();
632 }
633 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
634 bs->unregister_potential_barrier_node(this);
635 #ifdef ASSERT
636 // We will not actually delete the storage, but we'll make the node unusable.
637 *(address*)this = badAddress; // smash the C++ vtbl, probably
638 _in = _out = (Node**) badAddress;
639 _max = _cnt = _outmax = _outcnt = 0;
640 compile->remove_modified_node(this);
641 #endif
642 }
643
644 //------------------------------grow-------------------------------------------
645 // Grow the input array, making space for more edges
646 void Node::grow( uint len ) {
647 Arena* arena = Compile::current()->node_arena();
648 uint new_max = _max;
649 if( new_max == 0 ) {
650 _max = 4;
651 _in = (Node**)arena->Amalloc(4*sizeof(Node*));
652 Node** to = _in;
653 to[0] = NULL;
654 to[1] = NULL;
655 to[2] = NULL;
656 to[3] = NULL;
657 return;
658 }
659 while( new_max <= len ) new_max <<= 1; // Find next power-of-2
660 // Trimming to limit allows a uint8 to handle up to 255 edges.
661 // Previously I was using only powers-of-2 which peaked at 128 edges.
662 //if( new_max >= limit ) new_max = limit-1;
663 _in = (Node**)arena->Arealloc(_in, _max*sizeof(Node*), new_max*sizeof(Node*));
664 Copy::zero_to_bytes(&_in[_max], (new_max-_max)*sizeof(Node*)); // NULL all new space
665 _max = new_max; // Record new max length
666 // This assertion makes sure that Node::_max is wide enough to
667 // represent the numerical value of new_max.
668 assert(_max == new_max && _max > len, "int width of _max is too small");
669 }
670
671 //-----------------------------out_grow----------------------------------------
672 // Grow the input array, making space for more edges
673 void Node::out_grow( uint len ) {
674 assert(!is_top(), "cannot grow a top node's out array");
675 Arena* arena = Compile::current()->node_arena();
676 uint new_max = _outmax;
677 if( new_max == 0 ) {
678 _outmax = 4;
679 _out = (Node **)arena->Amalloc(4*sizeof(Node*));
680 return;
681 }
682 while( new_max <= len ) new_max <<= 1; // Find next power-of-2
683 // Trimming to limit allows a uint8 to handle up to 255 edges.
684 // Previously I was using only powers-of-2 which peaked at 128 edges.
685 //if( new_max >= limit ) new_max = limit-1;
686 assert(_out != NULL && _out != NO_OUT_ARRAY, "out must have sensible value");
687 _out = (Node**)arena->Arealloc(_out,_outmax*sizeof(Node*),new_max*sizeof(Node*));
688 //Copy::zero_to_bytes(&_out[_outmax], (new_max-_outmax)*sizeof(Node*)); // NULL all new space
689 _outmax = new_max; // Record new max length
690 // This assertion makes sure that Node::_max is wide enough to
691 // represent the numerical value of new_max.
692 assert(_outmax == new_max && _outmax > len, "int width of _outmax is too small");
693 }
694
695 #ifdef ASSERT
696 //------------------------------is_dead----------------------------------------
697 bool Node::is_dead() const {
698 // Mach and pinch point nodes may look like dead.
699 if( is_top() || is_Mach() || (Opcode() == Op_Node && _outcnt > 0) )
700 return false;
701 for( uint i = 0; i < _max; i++ )
702 if( _in[i] != NULL )
703 return false;
704 dump();
705 return true;
706 }
707 #endif
708
709
710 //------------------------------is_unreachable---------------------------------
711 bool Node::is_unreachable(PhaseIterGVN &igvn) const {
712 assert(!is_Mach(), "doesn't work with MachNodes");
713 return outcnt() == 0 || igvn.type(this) == Type::TOP || (in(0) != NULL && in(0)->is_top());
714 }
715
716 //------------------------------add_req----------------------------------------
717 // Add a new required input at the end
718 void Node::add_req( Node *n ) {
719 assert( is_not_dead(n), "can not use dead node");
720
721 // Look to see if I can move precedence down one without reallocating
722 if( (_cnt >= _max) || (in(_max-1) != NULL) )
723 grow( _max+1 );
724
725 // Find a precedence edge to move
726 if( in(_cnt) != NULL ) { // Next precedence edge is busy?
727 uint i;
728 for( i=_cnt; i<_max; i++ )
729 if( in(i) == NULL ) // Find the NULL at end of prec edge list
730 break; // There must be one, since we grew the array
731 _in[i] = in(_cnt); // Move prec over, making space for req edge
732 }
733 _in[_cnt++] = n; // Stuff over old prec edge
734 if (n != NULL) n->add_out((Node *)this);
735 }
736
737 //---------------------------add_req_batch-------------------------------------
738 // Add a new required input at the end
739 void Node::add_req_batch( Node *n, uint m ) {
740 assert( is_not_dead(n), "can not use dead node");
741 // check various edge cases
742 if ((int)m <= 1) {
743 assert((int)m >= 0, "oob");
744 if (m != 0) add_req(n);
745 return;
746 }
747
748 // Look to see if I can move precedence down one without reallocating
749 if( (_cnt+m) > _max || _in[_max-m] )
750 grow( _max+m );
751
752 // Find a precedence edge to move
753 if( _in[_cnt] != NULL ) { // Next precedence edge is busy?
754 uint i;
755 for( i=_cnt; i<_max; i++ )
756 if( _in[i] == NULL ) // Find the NULL at end of prec edge list
757 break; // There must be one, since we grew the array
758 // Slide all the precs over by m positions (assume #prec << m).
759 Copy::conjoint_words_to_higher((HeapWord*)&_in[_cnt], (HeapWord*)&_in[_cnt+m], ((i-_cnt)*sizeof(Node*)));
760 }
761
762 // Stuff over the old prec edges
763 for(uint i=0; i<m; i++ ) {
764 _in[_cnt++] = n;
765 }
766
767 // Insert multiple out edges on the node.
768 if (n != NULL && !n->is_top()) {
769 for(uint i=0; i<m; i++ ) {
770 n->add_out((Node *)this);
771 }
772 }
773 }
774
775 //------------------------------del_req----------------------------------------
776 // Delete the required edge and compact the edge array
777 void Node::del_req( uint idx ) {
778 assert( idx < _cnt, "oob");
779 assert( !VerifyHashTableKeys || _hash_lock == 0,
780 "remove node from hash table before modifying it");
781 // First remove corresponding def-use edge
782 Node *n = in(idx);
783 if (n != NULL) n->del_out((Node *)this);
784 _in[idx] = in(--_cnt); // Compact the array
785 // Avoid spec violation: Gap in prec edges.
786 close_prec_gap_at(_cnt);
787 Compile::current()->record_modified_node(this);
788 }
789
790 //------------------------------del_req_ordered--------------------------------
791 // Delete the required edge and compact the edge array with preserved order
792 void Node::del_req_ordered( uint idx ) {
793 assert( idx < _cnt, "oob");
794 assert( !VerifyHashTableKeys || _hash_lock == 0,
795 "remove node from hash table before modifying it");
796 // First remove corresponding def-use edge
797 Node *n = in(idx);
798 if (n != NULL) n->del_out((Node *)this);
799 if (idx < --_cnt) { // Not last edge ?
800 Copy::conjoint_words_to_lower((HeapWord*)&_in[idx+1], (HeapWord*)&_in[idx], ((_cnt-idx)*sizeof(Node*)));
801 }
802 // Avoid spec violation: Gap in prec edges.
803 close_prec_gap_at(_cnt);
804 Compile::current()->record_modified_node(this);
805 }
806
807 //------------------------------ins_req----------------------------------------
808 // Insert a new required input at the end
809 void Node::ins_req( uint idx, Node *n ) {
810 assert( is_not_dead(n), "can not use dead node");
811 add_req(NULL); // Make space
812 assert( idx < _max, "Must have allocated enough space");
813 // Slide over
814 if(_cnt-idx-1 > 0) {
815 Copy::conjoint_words_to_higher((HeapWord*)&_in[idx], (HeapWord*)&_in[idx+1], ((_cnt-idx-1)*sizeof(Node*)));
816 }
817 _in[idx] = n; // Stuff over old required edge
818 if (n != NULL) n->add_out((Node *)this); // Add reciprocal def-use edge
819 }
820
821 //-----------------------------find_edge---------------------------------------
822 int Node::find_edge(Node* n) {
823 for (uint i = 0; i < len(); i++) {
824 if (_in[i] == n) return i;
825 }
826 return -1;
827 }
828
829 //----------------------------replace_edge-------------------------------------
830 int Node::replace_edge(Node* old, Node* neww) {
831 if (old == neww) return 0; // nothing to do
832 uint nrep = 0;
833 for (uint i = 0; i < len(); i++) {
834 if (in(i) == old) {
835 if (i < req()) {
836 set_req(i, neww);
837 } else {
838 assert(find_prec_edge(neww) == -1, "spec violation: duplicated prec edge (node %d -> %d)", _idx, neww->_idx);
839 set_prec(i, neww);
840 }
841 nrep++;
842 }
843 }
844 return nrep;
845 }
846
847 /**
848 * Replace input edges in the range pointing to 'old' node.
849 */
850 int Node::replace_edges_in_range(Node* old, Node* neww, int start, int end) {
851 if (old == neww) return 0; // nothing to do
852 uint nrep = 0;
853 for (int i = start; i < end; i++) {
854 if (in(i) == old) {
855 set_req(i, neww);
856 nrep++;
857 }
858 }
859 return nrep;
860 }
861
862 //-------------------------disconnect_inputs-----------------------------------
863 // NULL out all inputs to eliminate incoming Def-Use edges.
864 // Return the number of edges between 'n' and 'this'
865 int Node::disconnect_inputs(Node *n, Compile* C) {
866 int edges_to_n = 0;
867
868 uint cnt = req();
869 for( uint i = 0; i < cnt; ++i ) {
870 if( in(i) == 0 ) continue;
871 if( in(i) == n ) ++edges_to_n;
872 set_req(i, NULL);
873 }
874 // Remove precedence edges if any exist
875 // Note: Safepoints may have precedence edges, even during parsing
876 if( (req() != len()) && (in(req()) != NULL) ) {
877 uint max = len();
878 for( uint i = 0; i < max; ++i ) {
879 if( in(i) == 0 ) continue;
880 if( in(i) == n ) ++edges_to_n;
881 set_prec(i, NULL);
882 }
883 }
884
885 // Node::destruct requires all out edges be deleted first
886 // debug_only(destruct();) // no reuse benefit expected
887 if (edges_to_n == 0) {
888 C->record_dead_node(_idx);
889 }
890 return edges_to_n;
891 }
892
893 //-----------------------------uncast---------------------------------------
894 // %%% Temporary, until we sort out CheckCastPP vs. CastPP.
895 // Strip away casting. (It is depth-limited.)
896 // Optionally, keep casts with dependencies.
897 Node* Node::uncast(bool keep_deps) const {
898 // Should be inline:
899 //return is_ConstraintCast() ? uncast_helper(this) : (Node*) this;
900 if (is_ConstraintCast()) {
901 return uncast_helper(this, keep_deps);
902 } else {
903 return (Node*) this;
904 }
905 }
906
907 // Find out of current node that matches opcode.
908 Node* Node::find_out_with(int opcode) {
909 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
910 Node* use = fast_out(i);
911 if (use->Opcode() == opcode) {
912 return use;
913 }
914 }
915 return NULL;
916 }
917
918 // Return true if the current node has an out that matches opcode.
919 bool Node::has_out_with(int opcode) {
920 return (find_out_with(opcode) != NULL);
921 }
922
923 // Return true if the current node has an out that matches any of the opcodes.
924 bool Node::has_out_with(int opcode1, int opcode2, int opcode3, int opcode4) {
925 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
926 int opcode = fast_out(i)->Opcode();
927 if (opcode == opcode1 || opcode == opcode2 || opcode == opcode3 || opcode == opcode4) {
928 return true;
929 }
930 }
931 return false;
932 }
933
934
935 //---------------------------uncast_helper-------------------------------------
936 Node* Node::uncast_helper(const Node* p, bool keep_deps) {
937 #ifdef ASSERT
938 uint depth_count = 0;
939 const Node* orig_p = p;
940 #endif
941
942 while (true) {
943 #ifdef ASSERT
944 if (depth_count >= K) {
945 orig_p->dump(4);
946 if (p != orig_p)
947 p->dump(1);
948 }
949 assert(depth_count++ < K, "infinite loop in Node::uncast_helper");
950 #endif
951 if (p == NULL || p->req() != 2) {
952 break;
953 } else if (p->is_ConstraintCast()) {
954 if (keep_deps && p->as_ConstraintCast()->carry_dependency()) {
955 break; // stop at casts with dependencies
956 }
957 p = p->in(1);
958 } else {
959 break;
960 }
961 }
962 return (Node*) p;
963 }
964
965 //------------------------------add_prec---------------------------------------
966 // Add a new precedence input. Precedence inputs are unordered, with
967 // duplicates removed and NULLs packed down at the end.
968 void Node::add_prec( Node *n ) {
969 assert( is_not_dead(n), "can not use dead node");
970
971 // Check for NULL at end
972 if( _cnt >= _max || in(_max-1) )
973 grow( _max+1 );
974
975 // Find a precedence edge to move
976 uint i = _cnt;
977 while( in(i) != NULL ) {
978 if (in(i) == n) return; // Avoid spec violation: duplicated prec edge.
979 i++;
980 }
981 _in[i] = n; // Stuff prec edge over NULL
982 if ( n != NULL) n->add_out((Node *)this); // Add mirror edge
983
984 #ifdef ASSERT
985 while ((++i)<_max) { assert(_in[i] == NULL, "spec violation: Gap in prec edges (node %d)", _idx); }
986 #endif
987 }
988
989 //------------------------------rm_prec----------------------------------------
990 // Remove a precedence input. Precedence inputs are unordered, with
991 // duplicates removed and NULLs packed down at the end.
992 void Node::rm_prec( uint j ) {
993 assert(j < _max, "oob: i=%d, _max=%d", j, _max);
994 assert(j >= _cnt, "not a precedence edge");
995 if (_in[j] == NULL) return; // Avoid spec violation: Gap in prec edges.
996 _in[j]->del_out((Node *)this);
997 close_prec_gap_at(j);
998 }
999
1000 //------------------------------size_of----------------------------------------
1001 uint Node::size_of() const { return sizeof(*this); }
1002
1003 //------------------------------ideal_reg--------------------------------------
1004 uint Node::ideal_reg() const { return 0; }
1005
1006 //------------------------------jvms-------------------------------------------
1007 JVMState* Node::jvms() const { return NULL; }
1008
1009 #ifdef ASSERT
1010 //------------------------------jvms-------------------------------------------
1011 bool Node::verify_jvms(const JVMState* using_jvms) const {
1012 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
1013 if (jvms == using_jvms) return true;
1014 }
1015 return false;
1016 }
1017
1018 //------------------------------init_NodeProperty------------------------------
1019 void Node::init_NodeProperty() {
1020 assert(_max_classes <= max_jushort, "too many NodeProperty classes");
1021 assert(_max_flags <= max_jushort, "too many NodeProperty flags");
1022 }
1023 #endif
1024
1025 //------------------------------format-----------------------------------------
1026 // Print as assembly
1027 void Node::format( PhaseRegAlloc *, outputStream *st ) const {}
1028 //------------------------------emit-------------------------------------------
1029 // Emit bytes starting at parameter 'ptr'.
1030 void Node::emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const {}
1031 //------------------------------size-------------------------------------------
1032 // Size of instruction in bytes
1033 uint Node::size(PhaseRegAlloc *ra_) const { return 0; }
1034
1035 //------------------------------CFG Construction-------------------------------
1036 // Nodes that end basic blocks, e.g. IfTrue/IfFalse, JumpProjNode, Root,
1037 // Goto and Return.
1038 const Node *Node::is_block_proj() const { return 0; }
1039
1040 // Minimum guaranteed type
1041 const Type *Node::bottom_type() const { return Type::BOTTOM; }
1042
1043
1044 //------------------------------raise_bottom_type------------------------------
1045 // Get the worst-case Type output for this Node.
1046 void Node::raise_bottom_type(const Type* new_type) {
1047 if (is_Type()) {
1048 TypeNode *n = this->as_Type();
1049 if (VerifyAliases) {
1050 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1051 }
1052 n->set_type(new_type);
1053 } else if (is_Load()) {
1054 LoadNode *n = this->as_Load();
1055 if (VerifyAliases) {
1056 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1057 }
1058 n->set_type(new_type);
1059 }
1060 }
1061
1062 //------------------------------Identity---------------------------------------
1063 // Return a node that the given node is equivalent to.
1064 Node* Node::Identity(PhaseGVN* phase) {
1065 return this; // Default to no identities
1066 }
1067
1068 //------------------------------Value------------------------------------------
1069 // Compute a new Type for a node using the Type of the inputs.
1070 const Type* Node::Value(PhaseGVN* phase) const {
1071 return bottom_type(); // Default to worst-case Type
1072 }
1073
1074 //------------------------------Ideal------------------------------------------
1075 //
1076 // 'Idealize' the graph rooted at this Node.
1077 //
1078 // In order to be efficient and flexible there are some subtle invariants
1079 // these Ideal calls need to hold. Running with '+VerifyIterativeGVN' checks
1080 // these invariants, although its too slow to have on by default. If you are
1081 // hacking an Ideal call, be sure to test with +VerifyIterativeGVN!
1082 //
1083 // The Ideal call almost arbitrarily reshape the graph rooted at the 'this'
1084 // pointer. If ANY change is made, it must return the root of the reshaped
1085 // graph - even if the root is the same Node. Example: swapping the inputs
1086 // to an AddINode gives the same answer and same root, but you still have to
1087 // return the 'this' pointer instead of NULL.
1088 //
1089 // You cannot return an OLD Node, except for the 'this' pointer. Use the
1090 // Identity call to return an old Node; basically if Identity can find
1091 // another Node have the Ideal call make no change and return NULL.
1092 // Example: AddINode::Ideal must check for add of zero; in this case it
1093 // returns NULL instead of doing any graph reshaping.
1094 //
1095 // You cannot modify any old Nodes except for the 'this' pointer. Due to
1096 // sharing there may be other users of the old Nodes relying on their current
1097 // semantics. Modifying them will break the other users.
1098 // Example: when reshape "(X+3)+4" into "X+7" you must leave the Node for
1099 // "X+3" unchanged in case it is shared.
1100 //
1101 // If you modify the 'this' pointer's inputs, you should use
1102 // 'set_req'. If you are making a new Node (either as the new root or
1103 // some new internal piece) you may use 'init_req' to set the initial
1104 // value. You can make a new Node with either 'new' or 'clone'. In
1105 // either case, def-use info is correctly maintained.
1106 //
1107 // Example: reshape "(X+3)+4" into "X+7":
1108 // set_req(1, in(1)->in(1));
1109 // set_req(2, phase->intcon(7));
1110 // return this;
1111 // Example: reshape "X*4" into "X<<2"
1112 // return new LShiftINode(in(1), phase->intcon(2));
1113 //
1114 // You must call 'phase->transform(X)' on any new Nodes X you make, except
1115 // for the returned root node. Example: reshape "X*31" with "(X<<5)-X".
1116 // Node *shift=phase->transform(new LShiftINode(in(1),phase->intcon(5)));
1117 // return new AddINode(shift, in(1));
1118 //
1119 // When making a Node for a constant use 'phase->makecon' or 'phase->intcon'.
1120 // These forms are faster than 'phase->transform(new ConNode())' and Do
1121 // The Right Thing with def-use info.
1122 //
1123 // You cannot bury the 'this' Node inside of a graph reshape. If the reshaped
1124 // graph uses the 'this' Node it must be the root. If you want a Node with
1125 // the same Opcode as the 'this' pointer use 'clone'.
1126 //
1127 Node *Node::Ideal(PhaseGVN *phase, bool can_reshape) {
1128 return NULL; // Default to being Ideal already
1129 }
1130
1131 // Some nodes have specific Ideal subgraph transformations only if they are
1132 // unique users of specific nodes. Such nodes should be put on IGVN worklist
1133 // for the transformations to happen.
1134 bool Node::has_special_unique_user() const {
1135 assert(outcnt() == 1, "match only for unique out");
1136 Node* n = unique_out();
1137 int op = Opcode();
1138 if (this->is_Store()) {
1139 // Condition for back-to-back stores folding.
1140 return n->Opcode() == op && n->in(MemNode::Memory) == this;
1141 } else if (this->is_Load() || this->is_DecodeN() || this->is_Phi()) {
1142 // Condition for removing an unused LoadNode or DecodeNNode from the MemBarAcquire precedence input
1143 return n->Opcode() == Op_MemBarAcquire;
1144 } else if (op == Op_AddL) {
1145 // Condition for convL2I(addL(x,y)) ==> addI(convL2I(x),convL2I(y))
1146 return n->Opcode() == Op_ConvL2I && n->in(1) == this;
1147 } else if (op == Op_SubI || op == Op_SubL) {
1148 // Condition for subI(x,subI(y,z)) ==> subI(addI(x,z),y)
1149 return n->Opcode() == op && n->in(2) == this;
1150 } else if (is_If() && (n->is_IfFalse() || n->is_IfTrue())) {
1151 // See IfProjNode::Identity()
1152 return true;
1153 } else {
1154 return BarrierSet::barrier_set()->barrier_set_c2()->has_special_unique_user(this);
1155 }
1156 };
1157
1158 //--------------------------find_exact_control---------------------------------
1159 // Skip Proj and CatchProj nodes chains. Check for Null and Top.
1160 Node* Node::find_exact_control(Node* ctrl) {
1161 if (ctrl == NULL && this->is_Region())
1162 ctrl = this->as_Region()->is_copy();
1163
1164 if (ctrl != NULL && ctrl->is_CatchProj()) {
1165 if (ctrl->as_CatchProj()->_con == CatchProjNode::fall_through_index)
1166 ctrl = ctrl->in(0);
1167 if (ctrl != NULL && !ctrl->is_top())
1168 ctrl = ctrl->in(0);
1169 }
1170
1171 if (ctrl != NULL && ctrl->is_Proj())
1172 ctrl = ctrl->in(0);
1173
1174 return ctrl;
1175 }
1176
1177 //--------------------------dominates------------------------------------------
1178 // Helper function for MemNode::all_controls_dominate().
1179 // Check if 'this' control node dominates or equal to 'sub' control node.
1180 // We already know that if any path back to Root or Start reaches 'this',
1181 // then all paths so, so this is a simple search for one example,
1182 // not an exhaustive search for a counterexample.
1183 bool Node::dominates(Node* sub, Node_List &nlist) {
1184 assert(this->is_CFG(), "expecting control");
1185 assert(sub != NULL && sub->is_CFG(), "expecting control");
1186
1187 // detect dead cycle without regions
1188 int iterations_without_region_limit = DominatorSearchLimit;
1189
1190 Node* orig_sub = sub;
1191 Node* dom = this;
1192 bool met_dom = false;
1193 nlist.clear();
1194
1195 // Walk 'sub' backward up the chain to 'dom', watching for regions.
1196 // After seeing 'dom', continue up to Root or Start.
1197 // If we hit a region (backward split point), it may be a loop head.
1198 // Keep going through one of the region's inputs. If we reach the
1199 // same region again, go through a different input. Eventually we
1200 // will either exit through the loop head, or give up.
1201 // (If we get confused, break out and return a conservative 'false'.)
1202 while (sub != NULL) {
1203 if (sub->is_top()) break; // Conservative answer for dead code.
1204 if (sub == dom) {
1205 if (nlist.size() == 0) {
1206 // No Region nodes except loops were visited before and the EntryControl
1207 // path was taken for loops: it did not walk in a cycle.
1208 return true;
1209 } else if (met_dom) {
1210 break; // already met before: walk in a cycle
1211 } else {
1212 // Region nodes were visited. Continue walk up to Start or Root
1213 // to make sure that it did not walk in a cycle.
1214 met_dom = true; // first time meet
1215 iterations_without_region_limit = DominatorSearchLimit; // Reset
1216 }
1217 }
1218 if (sub->is_Start() || sub->is_Root()) {
1219 // Success if we met 'dom' along a path to Start or Root.
1220 // We assume there are no alternative paths that avoid 'dom'.
1221 // (This assumption is up to the caller to ensure!)
1222 return met_dom;
1223 }
1224 Node* up = sub->in(0);
1225 // Normalize simple pass-through regions and projections:
1226 up = sub->find_exact_control(up);
1227 // If sub == up, we found a self-loop. Try to push past it.
1228 if (sub == up && sub->is_Loop()) {
1229 // Take loop entry path on the way up to 'dom'.
1230 up = sub->in(1); // in(LoopNode::EntryControl);
1231 } else if (sub == up && sub->is_Region() && sub->req() == 2) {
1232 // Take in(1) path on the way up to 'dom' for regions with only one input
1233 up = sub->in(1);
1234 } else if (sub == up && sub->is_Region() && sub->req() == 3) {
1235 // Try both paths for Regions with 2 input paths (it may be a loop head).
1236 // It could give conservative 'false' answer without information
1237 // which region's input is the entry path.
1238 iterations_without_region_limit = DominatorSearchLimit; // Reset
1239
1240 bool region_was_visited_before = false;
1241 // Was this Region node visited before?
1242 // If so, we have reached it because we accidentally took a
1243 // loop-back edge from 'sub' back into the body of the loop,
1244 // and worked our way up again to the loop header 'sub'.
1245 // So, take the first unexplored path on the way up to 'dom'.
1246 for (int j = nlist.size() - 1; j >= 0; j--) {
1247 intptr_t ni = (intptr_t)nlist.at(j);
1248 Node* visited = (Node*)(ni & ~1);
1249 bool visited_twice_already = ((ni & 1) != 0);
1250 if (visited == sub) {
1251 if (visited_twice_already) {
1252 // Visited 2 paths, but still stuck in loop body. Give up.
1253 return false;
1254 }
1255 // The Region node was visited before only once.
1256 // (We will repush with the low bit set, below.)
1257 nlist.remove(j);
1258 // We will find a new edge and re-insert.
1259 region_was_visited_before = true;
1260 break;
1261 }
1262 }
1263
1264 // Find an incoming edge which has not been seen yet; walk through it.
1265 assert(up == sub, "");
1266 uint skip = region_was_visited_before ? 1 : 0;
1267 for (uint i = 1; i < sub->req(); i++) {
1268 Node* in = sub->in(i);
1269 if (in != NULL && !in->is_top() && in != sub) {
1270 if (skip == 0) {
1271 up = in;
1272 break;
1273 }
1274 --skip; // skip this nontrivial input
1275 }
1276 }
1277
1278 // Set 0 bit to indicate that both paths were taken.
1279 nlist.push((Node*)((intptr_t)sub + (region_was_visited_before ? 1 : 0)));
1280 }
1281
1282 if (up == sub) {
1283 break; // some kind of tight cycle
1284 }
1285 if (up == orig_sub && met_dom) {
1286 // returned back after visiting 'dom'
1287 break; // some kind of cycle
1288 }
1289 if (--iterations_without_region_limit < 0) {
1290 break; // dead cycle
1291 }
1292 sub = up;
1293 }
1294
1295 // Did not meet Root or Start node in pred. chain.
1296 // Conservative answer for dead code.
1297 return false;
1298 }
1299
1300 //------------------------------remove_dead_region-----------------------------
1301 // This control node is dead. Follow the subgraph below it making everything
1302 // using it dead as well. This will happen normally via the usual IterGVN
1303 // worklist but this call is more efficient. Do not update use-def info
1304 // inside the dead region, just at the borders.
1305 static void kill_dead_code( Node *dead, PhaseIterGVN *igvn ) {
1306 // Con's are a popular node to re-hit in the hash table again.
1307 if( dead->is_Con() ) return;
1308
1309 ResourceMark rm;
1310 Node_List nstack(Thread::current()->resource_area());
1311
1312 Node *top = igvn->C->top();
1313 nstack.push(dead);
1314 bool has_irreducible_loop = igvn->C->has_irreducible_loop();
1315
1316 while (nstack.size() > 0) {
1317 dead = nstack.pop();
1318 if (dead->Opcode() == Op_SafePoint) {
1319 dead->as_SafePoint()->disconnect_from_root(igvn);
1320 }
1321 if (dead->outcnt() > 0) {
1322 // Keep dead node on stack until all uses are processed.
1323 nstack.push(dead);
1324 // For all Users of the Dead... ;-)
1325 for (DUIterator_Last kmin, k = dead->last_outs(kmin); k >= kmin; ) {
1326 Node* use = dead->last_out(k);
1327 igvn->hash_delete(use); // Yank from hash table prior to mod
1328 if (use->in(0) == dead) { // Found another dead node
1329 assert (!use->is_Con(), "Control for Con node should be Root node.");
1330 use->set_req(0, top); // Cut dead edge to prevent processing
1331 nstack.push(use); // the dead node again.
1332 } else if (!has_irreducible_loop && // Backedge could be alive in irreducible loop
1333 use->is_Loop() && !use->is_Root() && // Don't kill Root (RootNode extends LoopNode)
1334 use->in(LoopNode::EntryControl) == dead) { // Dead loop if its entry is dead
1335 use->set_req(LoopNode::EntryControl, top); // Cut dead edge to prevent processing
1336 use->set_req(0, top); // Cut self edge
1337 nstack.push(use);
1338 } else { // Else found a not-dead user
1339 // Dead if all inputs are top or null
1340 bool dead_use = !use->is_Root(); // Keep empty graph alive
1341 for (uint j = 1; j < use->req(); j++) {
1342 Node* in = use->in(j);
1343 if (in == dead) { // Turn all dead inputs into TOP
1344 use->set_req(j, top);
1345 } else if (in != NULL && !in->is_top()) {
1346 dead_use = false;
1347 }
1348 }
1349 if (dead_use) {
1350 if (use->is_Region()) {
1351 use->set_req(0, top); // Cut self edge
1352 }
1353 nstack.push(use);
1354 } else {
1355 igvn->_worklist.push(use);
1356 }
1357 }
1358 // Refresh the iterator, since any number of kills might have happened.
1359 k = dead->last_outs(kmin);
1360 }
1361 } else { // (dead->outcnt() == 0)
1362 // Done with outputs.
1363 igvn->hash_delete(dead);
1364 igvn->_worklist.remove(dead);
1365 igvn->C->remove_modified_node(dead);
1366 igvn->set_type(dead, Type::TOP);
1367 if (dead->is_macro()) {
1368 igvn->C->remove_macro_node(dead);
1369 }
1370 if (dead->is_expensive()) {
1371 igvn->C->remove_expensive_node(dead);
1372 }
1373 CastIINode* cast = dead->isa_CastII();
1374 if (cast != NULL && cast->has_range_check()) {
1375 igvn->C->remove_range_check_cast(cast);
1376 }
1377 if (dead->Opcode() == Op_Opaque4) {
1378 igvn->C->remove_opaque4_node(dead);
1379 }
1380 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1381 bs->unregister_potential_barrier_node(dead);
1382 igvn->C->record_dead_node(dead->_idx);
1383 // Kill all inputs to the dead guy
1384 for (uint i=0; i < dead->req(); i++) {
1385 Node *n = dead->in(i); // Get input to dead guy
1386 if (n != NULL && !n->is_top()) { // Input is valid?
1387 dead->set_req(i, top); // Smash input away
1388 if (n->outcnt() == 0) { // Input also goes dead?
1389 if (!n->is_Con())
1390 nstack.push(n); // Clear it out as well
1391 } else if (n->outcnt() == 1 &&
1392 n->has_special_unique_user()) {
1393 igvn->add_users_to_worklist( n );
1394 } else if (n->outcnt() <= 2 && n->is_Store()) {
1395 // Push store's uses on worklist to enable folding optimization for
1396 // store/store and store/load to the same address.
1397 // The restriction (outcnt() <= 2) is the same as in set_req_X()
1398 // and remove_globally_dead_node().
1399 igvn->add_users_to_worklist( n );
1400 } else {
1401 BarrierSet::barrier_set()->barrier_set_c2()->enqueue_useful_gc_barrier(igvn, n);
1402 }
1403 }
1404 }
1405 } // (dead->outcnt() == 0)
1406 } // while (nstack.size() > 0) for outputs
1407 return;
1408 }
1409
1410 //------------------------------remove_dead_region-----------------------------
1411 bool Node::remove_dead_region(PhaseGVN *phase, bool can_reshape) {
1412 Node *n = in(0);
1413 if( !n ) return false;
1414 // Lost control into this guy? I.e., it became unreachable?
1415 // Aggressively kill all unreachable code.
1416 if (can_reshape && n->is_top()) {
1417 kill_dead_code(this, phase->is_IterGVN());
1418 return false; // Node is dead.
1419 }
1420
1421 if( n->is_Region() && n->as_Region()->is_copy() ) {
1422 Node *m = n->nonnull_req();
1423 set_req(0, m);
1424 return true;
1425 }
1426 return false;
1427 }
1428
1429 //------------------------------hash-------------------------------------------
1430 // Hash function over Nodes.
1431 uint Node::hash() const {
1432 uint sum = 0;
1433 for( uint i=0; i<_cnt; i++ ) // Add in all inputs
1434 sum = (sum<<1)-(uintptr_t)in(i); // Ignore embedded NULLs
1435 return (sum>>2) + _cnt + Opcode();
1436 }
1437
1438 //------------------------------cmp--------------------------------------------
1439 // Compare special parts of simple Nodes
1440 bool Node::cmp( const Node &n ) const {
1441 return true; // Must be same
1442 }
1443
1444 //------------------------------rematerialize-----------------------------------
1445 // Should we clone rather than spill this instruction?
1446 bool Node::rematerialize() const {
1447 if ( is_Mach() )
1448 return this->as_Mach()->rematerialize();
1449 else
1450 return (_flags & Flag_rematerialize) != 0;
1451 }
1452
1453 //------------------------------needs_anti_dependence_check---------------------
1454 // Nodes which use memory without consuming it, hence need antidependences.
1455 bool Node::needs_anti_dependence_check() const {
1456 if (req() < 2 || (_flags & Flag_needs_anti_dependence_check) == 0) {
1457 return false;
1458 }
1459 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1460 if (!bs->needs_anti_dependence_check(this)) {
1461 return false;
1462 }
1463 return in(1)->bottom_type()->has_memory();
1464 }
1465
1466 // Get an integer constant from a ConNode (or CastIINode).
1467 // Return a default value if there is no apparent constant here.
1468 const TypeInt* Node::find_int_type() const {
1469 if (this->is_Type()) {
1470 return this->as_Type()->type()->isa_int();
1471 } else if (this->is_Con()) {
1472 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1473 return this->bottom_type()->isa_int();
1474 }
1475 return NULL;
1476 }
1477
1478 // Get a pointer constant from a ConstNode.
1479 // Returns the constant if it is a pointer ConstNode
1480 intptr_t Node::get_ptr() const {
1481 assert( Opcode() == Op_ConP, "" );
1482 return ((ConPNode*)this)->type()->is_ptr()->get_con();
1483 }
1484
1485 // Get a narrow oop constant from a ConNNode.
1486 intptr_t Node::get_narrowcon() const {
1487 assert( Opcode() == Op_ConN, "" );
1488 return ((ConNNode*)this)->type()->is_narrowoop()->get_con();
1489 }
1490
1491 // Get a long constant from a ConNode.
1492 // Return a default value if there is no apparent constant here.
1493 const TypeLong* Node::find_long_type() const {
1494 if (this->is_Type()) {
1495 return this->as_Type()->type()->isa_long();
1496 } else if (this->is_Con()) {
1497 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1498 return this->bottom_type()->isa_long();
1499 }
1500 return NULL;
1501 }
1502
1503
1504 /**
1505 * Return a ptr type for nodes which should have it.
1506 */
1507 const TypePtr* Node::get_ptr_type() const {
1508 const TypePtr* tp = this->bottom_type()->make_ptr();
1509 #ifdef ASSERT
1510 if (tp == NULL) {
1511 this->dump(1);
1512 assert((tp != NULL), "unexpected node type");
1513 }
1514 #endif
1515 return tp;
1516 }
1517
1518 // Get a double constant from a ConstNode.
1519 // Returns the constant if it is a double ConstNode
1520 jdouble Node::getd() const {
1521 assert( Opcode() == Op_ConD, "" );
1522 return ((ConDNode*)this)->type()->is_double_constant()->getd();
1523 }
1524
1525 // Get a float constant from a ConstNode.
1526 // Returns the constant if it is a float ConstNode
1527 jfloat Node::getf() const {
1528 assert( Opcode() == Op_ConF, "" );
1529 return ((ConFNode*)this)->type()->is_float_constant()->getf();
1530 }
1531
1532 #ifndef PRODUCT
1533
1534 //------------------------------find------------------------------------------
1535 // Find a neighbor of this Node with the given _idx
1536 // If idx is negative, find its absolute value, following both _in and _out.
1537 static void find_recur(Compile* C, Node* &result, Node *n, int idx, bool only_ctrl,
1538 VectorSet* old_space, VectorSet* new_space ) {
1539 int node_idx = (idx >= 0) ? idx : -idx;
1540 if (NotANode(n)) return; // Gracefully handle NULL, -1, 0xabababab, etc.
1541 // Contained in new_space or old_space? Check old_arena first since it's mostly empty.
1542 VectorSet *v = C->old_arena()->contains(n) ? old_space : new_space;
1543 if( v->test(n->_idx) ) return;
1544 if( (int)n->_idx == node_idx
1545 debug_only(|| n->debug_idx() == node_idx) ) {
1546 if (result != NULL)
1547 tty->print("find: " INTPTR_FORMAT " and " INTPTR_FORMAT " both have idx==%d\n",
1548 (uintptr_t)result, (uintptr_t)n, node_idx);
1549 result = n;
1550 }
1551 v->set(n->_idx);
1552 for( uint i=0; i<n->len(); i++ ) {
1553 if( only_ctrl && !(n->is_Region()) && (n->Opcode() != Op_Root) && (i != TypeFunc::Control) ) continue;
1554 find_recur(C, result, n->in(i), idx, only_ctrl, old_space, new_space );
1555 }
1556 // Search along forward edges also:
1557 if (idx < 0 && !only_ctrl) {
1558 for( uint j=0; j<n->outcnt(); j++ ) {
1559 find_recur(C, result, n->raw_out(j), idx, only_ctrl, old_space, new_space );
1560 }
1561 }
1562 #ifdef ASSERT
1563 // Search along debug_orig edges last, checking for cycles
1564 Node* orig = n->debug_orig();
1565 if (orig != NULL) {
1566 do {
1567 if (NotANode(orig)) break;
1568 find_recur(C, result, orig, idx, only_ctrl, old_space, new_space );
1569 orig = orig->debug_orig();
1570 } while (orig != NULL && orig != n->debug_orig());
1571 }
1572 #endif //ASSERT
1573 }
1574
1575 // call this from debugger:
1576 Node* find_node(Node* n, int idx) {
1577 return n->find(idx);
1578 }
1579
1580 //------------------------------find-------------------------------------------
1581 Node* Node::find(int idx) const {
1582 ResourceArea *area = Thread::current()->resource_area();
1583 VectorSet old_space(area), new_space(area);
1584 Node* result = NULL;
1585 find_recur(Compile::current(), result, (Node*) this, idx, false, &old_space, &new_space );
1586 return result;
1587 }
1588
1589 //------------------------------find_ctrl--------------------------------------
1590 // Find an ancestor to this node in the control history with given _idx
1591 Node* Node::find_ctrl(int idx) const {
1592 ResourceArea *area = Thread::current()->resource_area();
1593 VectorSet old_space(area), new_space(area);
1594 Node* result = NULL;
1595 find_recur(Compile::current(), result, (Node*) this, idx, true, &old_space, &new_space );
1596 return result;
1597 }
1598 #endif
1599
1600
1601
1602 #ifndef PRODUCT
1603
1604 // -----------------------------Name-------------------------------------------
1605 extern const char *NodeClassNames[];
1606 const char *Node::Name() const { return NodeClassNames[Opcode()]; }
1607
1608 static bool is_disconnected(const Node* n) {
1609 for (uint i = 0; i < n->req(); i++) {
1610 if (n->in(i) != NULL) return false;
1611 }
1612 return true;
1613 }
1614
1615 #ifdef ASSERT
1616 static void dump_orig(Node* orig, outputStream *st) {
1617 Compile* C = Compile::current();
1618 if (NotANode(orig)) orig = NULL;
1619 if (orig != NULL && !C->node_arena()->contains(orig)) orig = NULL;
1620 if (orig == NULL) return;
1621 st->print(" !orig=");
1622 Node* fast = orig->debug_orig(); // tortoise & hare algorithm to detect loops
1623 if (NotANode(fast)) fast = NULL;
1624 while (orig != NULL) {
1625 bool discon = is_disconnected(orig); // if discon, print [123] else 123
1626 if (discon) st->print("[");
1627 if (!Compile::current()->node_arena()->contains(orig))
1628 st->print("o");
1629 st->print("%d", orig->_idx);
1630 if (discon) st->print("]");
1631 orig = orig->debug_orig();
1632 if (NotANode(orig)) orig = NULL;
1633 if (orig != NULL && !C->node_arena()->contains(orig)) orig = NULL;
1634 if (orig != NULL) st->print(",");
1635 if (fast != NULL) {
1636 // Step fast twice for each single step of orig:
1637 fast = fast->debug_orig();
1638 if (NotANode(fast)) fast = NULL;
1639 if (fast != NULL && fast != orig) {
1640 fast = fast->debug_orig();
1641 if (NotANode(fast)) fast = NULL;
1642 }
1643 if (fast == orig) {
1644 st->print("...");
1645 break;
1646 }
1647 }
1648 }
1649 }
1650
1651 void Node::set_debug_orig(Node* orig) {
1652 _debug_orig = orig;
1653 if (BreakAtNode == 0) return;
1654 if (NotANode(orig)) orig = NULL;
1655 int trip = 10;
1656 while (orig != NULL) {
1657 if (orig->debug_idx() == BreakAtNode || (int)orig->_idx == BreakAtNode) {
1658 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=%d orig._idx=%d orig._debug_idx=%d",
1659 this->_idx, this->debug_idx(), orig->_idx, orig->debug_idx());
1660 BREAKPOINT;
1661 }
1662 orig = orig->debug_orig();
1663 if (NotANode(orig)) orig = NULL;
1664 if (trip-- <= 0) break;
1665 }
1666 }
1667 #endif //ASSERT
1668
1669 //------------------------------dump------------------------------------------
1670 // Dump a Node
1671 void Node::dump(const char* suffix, bool mark, outputStream *st) const {
1672 Compile* C = Compile::current();
1673 bool is_new = C->node_arena()->contains(this);
1674 C->_in_dump_cnt++;
1675 st->print("%c%d%s\t%s\t=== ", is_new ? ' ' : 'o', _idx, mark ? " >" : "", Name());
1676
1677 // Dump the required and precedence inputs
1678 dump_req(st);
1679 dump_prec(st);
1680 // Dump the outputs
1681 dump_out(st);
1682
1683 if (is_disconnected(this)) {
1684 #ifdef ASSERT
1685 st->print(" [%d]",debug_idx());
1686 dump_orig(debug_orig(), st);
1687 #endif
1688 st->cr();
1689 C->_in_dump_cnt--;
1690 return; // don't process dead nodes
1691 }
1692
1693 if (C->clone_map().value(_idx) != 0) {
1694 C->clone_map().dump(_idx);
1695 }
1696 // Dump node-specific info
1697 dump_spec(st);
1698 #ifdef ASSERT
1699 // Dump the non-reset _debug_idx
1700 if (Verbose && WizardMode) {
1701 st->print(" [%d]",debug_idx());
1702 }
1703 #endif
1704
1705 const Type *t = bottom_type();
1706
1707 if (t != NULL && (t->isa_instptr() || t->isa_klassptr())) {
1708 const TypeInstPtr *toop = t->isa_instptr();
1709 const TypeKlassPtr *tkls = t->isa_klassptr();
1710 ciKlass* klass = toop ? toop->klass() : (tkls ? tkls->klass() : NULL );
1711 if (klass && klass->is_loaded() && klass->is_interface()) {
1712 st->print(" Interface:");
1713 } else if (toop) {
1714 st->print(" Oop:");
1715 } else if (tkls) {
1716 st->print(" Klass:");
1717 }
1718 t->dump_on(st);
1719 } else if (t == Type::MEMORY) {
1720 st->print(" Memory:");
1721 MemNode::dump_adr_type(this, adr_type(), st);
1722 } else if (Verbose || WizardMode) {
1723 st->print(" Type:");
1724 if (t) {
1725 t->dump_on(st);
1726 } else {
1727 st->print("no type");
1728 }
1729 } else if (t->isa_vect() && this->is_MachSpillCopy()) {
1730 // Dump MachSpillcopy vector type.
1731 t->dump_on(st);
1732 }
1733 if (is_new) {
1734 debug_only(dump_orig(debug_orig(), st));
1735 Node_Notes* nn = C->node_notes_at(_idx);
1736 if (nn != NULL && !nn->is_clear()) {
1737 if (nn->jvms() != NULL) {
1738 st->print(" !jvms:");
1739 nn->jvms()->dump_spec(st);
1740 }
1741 }
1742 }
1743 if (suffix) st->print("%s", suffix);
1744 C->_in_dump_cnt--;
1745 }
1746
1747 //------------------------------dump_req--------------------------------------
1748 void Node::dump_req(outputStream *st) const {
1749 // Dump the required input edges
1750 for (uint i = 0; i < req(); i++) { // For all required inputs
1751 Node* d = in(i);
1752 if (d == NULL) {
1753 st->print("_ ");
1754 } else if (NotANode(d)) {
1755 st->print("NotANode "); // uninitialized, sentinel, garbage, etc.
1756 } else {
1757 st->print("%c%d ", Compile::current()->node_arena()->contains(d) ? ' ' : 'o', d->_idx);
1758 }
1759 }
1760 }
1761
1762
1763 //------------------------------dump_prec-------------------------------------
1764 void Node::dump_prec(outputStream *st) const {
1765 // Dump the precedence edges
1766 int any_prec = 0;
1767 for (uint i = req(); i < len(); i++) { // For all precedence inputs
1768 Node* p = in(i);
1769 if (p != NULL) {
1770 if (!any_prec++) st->print(" |");
1771 if (NotANode(p)) { st->print("NotANode "); continue; }
1772 st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx);
1773 }
1774 }
1775 }
1776
1777 //------------------------------dump_out--------------------------------------
1778 void Node::dump_out(outputStream *st) const {
1779 // Delimit the output edges
1780 st->print(" [[");
1781 // Dump the output edges
1782 for (uint i = 0; i < _outcnt; i++) { // For all outputs
1783 Node* u = _out[i];
1784 if (u == NULL) {
1785 st->print("_ ");
1786 } else if (NotANode(u)) {
1787 st->print("NotANode ");
1788 } else {
1789 st->print("%c%d ", Compile::current()->node_arena()->contains(u) ? ' ' : 'o', u->_idx);
1790 }
1791 }
1792 st->print("]] ");
1793 }
1794
1795 //----------------------------collect_nodes_i----------------------------------
1796 // Collects nodes from an Ideal graph, starting from a given start node and
1797 // moving in a given direction until a certain depth (distance from the start
1798 // node) is reached. Duplicates are ignored.
1799 // Arguments:
1800 // nstack: the nodes are collected into this array.
1801 // start: the node at which to start collecting.
1802 // direction: if this is a positive number, collect input nodes; if it is
1803 // a negative number, collect output nodes.
1804 // depth: collect nodes up to this distance from the start node.
1805 // include_start: whether to include the start node in the result collection.
1806 // only_ctrl: whether to regard control edges only during traversal.
1807 // only_data: whether to regard data edges only during traversal.
1808 static void collect_nodes_i(GrowableArray<Node*> *nstack, const Node* start, int direction, uint depth, bool include_start, bool only_ctrl, bool only_data) {
1809 Node* s = (Node*) start; // remove const
1810 nstack->append(s);
1811 int begin = 0;
1812 int end = 0;
1813 for(uint i = 0; i < depth; i++) {
1814 end = nstack->length();
1815 for(int j = begin; j < end; j++) {
1816 Node* tp = nstack->at(j);
1817 uint limit = direction > 0 ? tp->len() : tp->outcnt();
1818 for(uint k = 0; k < limit; k++) {
1819 Node* n = direction > 0 ? tp->in(k) : tp->raw_out(k);
1820
1821 if (NotANode(n)) continue;
1822 // do not recurse through top or the root (would reach unrelated stuff)
1823 if (n->is_Root() || n->is_top()) continue;
1824 if (only_ctrl && !n->is_CFG()) continue;
1825 if (only_data && n->is_CFG()) continue;
1826
1827 bool on_stack = nstack->contains(n);
1828 if (!on_stack) {
1829 nstack->append(n);
1830 }
1831 }
1832 }
1833 begin = end;
1834 }
1835 if (!include_start) {
1836 nstack->remove(s);
1837 }
1838 }
1839
1840 //------------------------------dump_nodes-------------------------------------
1841 static void dump_nodes(const Node* start, int d, bool only_ctrl) {
1842 if (NotANode(start)) return;
1843
1844 GrowableArray <Node *> nstack(Compile::current()->live_nodes());
1845 collect_nodes_i(&nstack, start, d, (uint) ABS(d), true, only_ctrl, false);
1846
1847 int end = nstack.length();
1848 if (d > 0) {
1849 for(int j = end-1; j >= 0; j--) {
1850 nstack.at(j)->dump();
1851 }
1852 } else {
1853 for(int j = 0; j < end; j++) {
1854 nstack.at(j)->dump();
1855 }
1856 }
1857 }
1858
1859 //------------------------------dump-------------------------------------------
1860 void Node::dump(int d) const {
1861 dump_nodes(this, d, false);
1862 }
1863
1864 //------------------------------dump_ctrl--------------------------------------
1865 // Dump a Node's control history to depth
1866 void Node::dump_ctrl(int d) const {
1867 dump_nodes(this, d, true);
1868 }
1869
1870 //-----------------------------dump_compact------------------------------------
1871 void Node::dump_comp() const {
1872 this->dump_comp("\n");
1873 }
1874
1875 //-----------------------------dump_compact------------------------------------
1876 // Dump a Node in compact representation, i.e., just print its name and index.
1877 // Nodes can specify additional specifics to print in compact representation by
1878 // implementing dump_compact_spec.
1879 void Node::dump_comp(const char* suffix, outputStream *st) const {
1880 Compile* C = Compile::current();
1881 C->_in_dump_cnt++;
1882 st->print("%s(%d)", Name(), _idx);
1883 this->dump_compact_spec(st);
1884 if (suffix) {
1885 st->print("%s", suffix);
1886 }
1887 C->_in_dump_cnt--;
1888 }
1889
1890 //----------------------------dump_related-------------------------------------
1891 // Dump a Node's related nodes - the notion of "related" depends on the Node at
1892 // hand and is determined by the implementation of the virtual method rel.
1893 void Node::dump_related() const {
1894 Compile* C = Compile::current();
1895 GrowableArray <Node *> in_rel(C->unique());
1896 GrowableArray <Node *> out_rel(C->unique());
1897 this->related(&in_rel, &out_rel, false);
1898 for (int i = in_rel.length() - 1; i >= 0; i--) {
1899 in_rel.at(i)->dump();
1900 }
1901 this->dump("\n", true);
1902 for (int i = 0; i < out_rel.length(); i++) {
1903 out_rel.at(i)->dump();
1904 }
1905 }
1906
1907 //----------------------------dump_related-------------------------------------
1908 // Dump a Node's related nodes up to a given depth (distance from the start
1909 // node).
1910 // Arguments:
1911 // d_in: depth for input nodes.
1912 // d_out: depth for output nodes (note: this also is a positive number).
1913 void Node::dump_related(uint d_in, uint d_out) const {
1914 Compile* C = Compile::current();
1915 GrowableArray <Node *> in_rel(C->unique());
1916 GrowableArray <Node *> out_rel(C->unique());
1917
1918 // call collect_nodes_i directly
1919 collect_nodes_i(&in_rel, this, 1, d_in, false, false, false);
1920 collect_nodes_i(&out_rel, this, -1, d_out, false, false, false);
1921
1922 for (int i = in_rel.length() - 1; i >= 0; i--) {
1923 in_rel.at(i)->dump();
1924 }
1925 this->dump("\n", true);
1926 for (int i = 0; i < out_rel.length(); i++) {
1927 out_rel.at(i)->dump();
1928 }
1929 }
1930
1931 //------------------------dump_related_compact---------------------------------
1932 // Dump a Node's related nodes in compact representation. The notion of
1933 // "related" depends on the Node at hand and is determined by the implementation
1934 // of the virtual method rel.
1935 void Node::dump_related_compact() const {
1936 Compile* C = Compile::current();
1937 GrowableArray <Node *> in_rel(C->unique());
1938 GrowableArray <Node *> out_rel(C->unique());
1939 this->related(&in_rel, &out_rel, true);
1940 int n_in = in_rel.length();
1941 int n_out = out_rel.length();
1942
1943 this->dump_comp(n_in == 0 ? "\n" : " ");
1944 for (int i = 0; i < n_in; i++) {
1945 in_rel.at(i)->dump_comp(i == n_in - 1 ? "\n" : " ");
1946 }
1947 for (int i = 0; i < n_out; i++) {
1948 out_rel.at(i)->dump_comp(i == n_out - 1 ? "\n" : " ");
1949 }
1950 }
1951
1952 //------------------------------related----------------------------------------
1953 // Collect a Node's related nodes. The default behaviour just collects the
1954 // inputs and outputs at depth 1, including both control and data flow edges,
1955 // regardless of whether the presentation is compact or not. For data nodes,
1956 // the default is to collect all data inputs (till level 1 if compact), and
1957 // outputs till level 1.
1958 void Node::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
1959 if (this->is_CFG()) {
1960 collect_nodes_i(in_rel, this, 1, 1, false, false, false);
1961 collect_nodes_i(out_rel, this, -1, 1, false, false, false);
1962 } else {
1963 if (compact) {
1964 this->collect_nodes(in_rel, 1, false, true);
1965 } else {
1966 this->collect_nodes_in_all_data(in_rel, false);
1967 }
1968 this->collect_nodes(out_rel, -1, false, false);
1969 }
1970 }
1971
1972 //---------------------------collect_nodes-------------------------------------
1973 // An entry point to the low-level node collection facility, to start from a
1974 // given node in the graph. The start node is by default not included in the
1975 // result.
1976 // Arguments:
1977 // ns: collect the nodes into this data structure.
1978 // d: the depth (distance from start node) to which nodes should be
1979 // collected. A value >0 indicates input nodes, a value <0, output
1980 // nodes.
1981 // ctrl: include only control nodes.
1982 // data: include only data nodes.
1983 void Node::collect_nodes(GrowableArray<Node*> *ns, int d, bool ctrl, bool data) const {
1984 if (ctrl && data) {
1985 // ignore nonsensical combination
1986 return;
1987 }
1988 collect_nodes_i(ns, this, d, (uint) ABS(d), false, ctrl, data);
1989 }
1990
1991 //--------------------------collect_nodes_in-----------------------------------
1992 static void collect_nodes_in(Node* start, GrowableArray<Node*> *ns, bool primary_is_data, bool collect_secondary) {
1993 // The maximum depth is determined using a BFS that visits all primary (data
1994 // or control) inputs and increments the depth at each level.
1995 uint d_in = 0;
1996 GrowableArray<Node*> nodes(Compile::current()->unique());
1997 nodes.push(start);
1998 int nodes_at_current_level = 1;
1999 int n_idx = 0;
2000 while (nodes_at_current_level > 0) {
2001 // Add all primary inputs reachable from the current level to the list, and
2002 // increase the depth if there were any.
2003 int nodes_at_next_level = 0;
2004 bool nodes_added = false;
2005 while (nodes_at_current_level > 0) {
2006 nodes_at_current_level--;
2007 Node* current = nodes.at(n_idx++);
2008 for (uint i = 0; i < current->len(); i++) {
2009 Node* n = current->in(i);
2010 if (NotANode(n)) {
2011 continue;
2012 }
2013 if ((primary_is_data && n->is_CFG()) || (!primary_is_data && !n->is_CFG())) {
2014 continue;
2015 }
2016 if (!nodes.contains(n)) {
2017 nodes.push(n);
2018 nodes_added = true;
2019 nodes_at_next_level++;
2020 }
2021 }
2022 }
2023 if (nodes_added) {
2024 d_in++;
2025 }
2026 nodes_at_current_level = nodes_at_next_level;
2027 }
2028 start->collect_nodes(ns, d_in, !primary_is_data, primary_is_data);
2029 if (collect_secondary) {
2030 // Now, iterate over the secondary nodes in ns and add the respective
2031 // boundary reachable from them.
2032 GrowableArray<Node*> sns(Compile::current()->unique());
2033 for (GrowableArrayIterator<Node*> it = ns->begin(); it != ns->end(); ++it) {
2034 Node* n = *it;
2035 n->collect_nodes(&sns, 1, primary_is_data, !primary_is_data);
2036 for (GrowableArrayIterator<Node*> d = sns.begin(); d != sns.end(); ++d) {
2037 ns->append_if_missing(*d);
2038 }
2039 sns.clear();
2040 }
2041 }
2042 }
2043
2044 //---------------------collect_nodes_in_all_data-------------------------------
2045 // Collect the entire data input graph. Include the control boundary if
2046 // requested.
2047 // Arguments:
2048 // ns: collect the nodes into this data structure.
2049 // ctrl: if true, include the control boundary.
2050 void Node::collect_nodes_in_all_data(GrowableArray<Node*> *ns, bool ctrl) const {
2051 collect_nodes_in((Node*) this, ns, true, ctrl);
2052 }
2053
2054 //--------------------------collect_nodes_in_all_ctrl--------------------------
2055 // Collect the entire control input graph. Include the data boundary if
2056 // requested.
2057 // ns: collect the nodes into this data structure.
2058 // data: if true, include the control boundary.
2059 void Node::collect_nodes_in_all_ctrl(GrowableArray<Node*> *ns, bool data) const {
2060 collect_nodes_in((Node*) this, ns, false, data);
2061 }
2062
2063 //------------------collect_nodes_out_all_ctrl_boundary------------------------
2064 // Collect the entire output graph until hitting control node boundaries, and
2065 // include those.
2066 void Node::collect_nodes_out_all_ctrl_boundary(GrowableArray<Node*> *ns) const {
2067 // Perform a BFS and stop at control nodes.
2068 GrowableArray<Node*> nodes(Compile::current()->unique());
2069 nodes.push((Node*) this);
2070 while (nodes.length() > 0) {
2071 Node* current = nodes.pop();
2072 if (NotANode(current)) {
2073 continue;
2074 }
2075 ns->append_if_missing(current);
2076 if (!current->is_CFG()) {
2077 for (DUIterator i = current->outs(); current->has_out(i); i++) {
2078 nodes.push(current->out(i));
2079 }
2080 }
2081 }
2082 ns->remove((Node*) this);
2083 }
2084
2085 // VERIFICATION CODE
2086 // For each input edge to a node (ie - for each Use-Def edge), verify that
2087 // there is a corresponding Def-Use edge.
2088 //------------------------------verify_edges-----------------------------------
2089 void Node::verify_edges(Unique_Node_List &visited) {
2090 uint i, j, idx;
2091 int cnt;
2092 Node *n;
2093
2094 // Recursive termination test
2095 if (visited.member(this)) return;
2096 visited.push(this);
2097
2098 // Walk over all input edges, checking for correspondence
2099 for( i = 0; i < len(); i++ ) {
2100 n = in(i);
2101 if (n != NULL && !n->is_top()) {
2102 // Count instances of (Node *)this
2103 cnt = 0;
2104 for (idx = 0; idx < n->_outcnt; idx++ ) {
2105 if (n->_out[idx] == (Node *)this) cnt++;
2106 }
2107 assert( cnt > 0,"Failed to find Def-Use edge." );
2108 // Check for duplicate edges
2109 // walk the input array downcounting the input edges to n
2110 for( j = 0; j < len(); j++ ) {
2111 if( in(j) == n ) cnt--;
2112 }
2113 assert( cnt == 0,"Mismatched edge count.");
2114 } else if (n == NULL) {
2115 assert(i >= req() || i == 0 || is_Region() || is_Phi(), "only regions or phis have null data edges");
2116 } else {
2117 assert(n->is_top(), "sanity");
2118 // Nothing to check.
2119 }
2120 }
2121 // Recursive walk over all input edges
2122 for( i = 0; i < len(); i++ ) {
2123 n = in(i);
2124 if( n != NULL )
2125 in(i)->verify_edges(visited);
2126 }
2127 }
2128
2129 //------------------------------verify_recur-----------------------------------
2130 static const Node *unique_top = NULL;
2131
2132 void Node::verify_recur(const Node *n, int verify_depth,
2133 VectorSet &old_space, VectorSet &new_space) {
2134 if ( verify_depth == 0 ) return;
2135 if (verify_depth > 0) --verify_depth;
2136
2137 Compile* C = Compile::current();
2138
2139 // Contained in new_space or old_space?
2140 VectorSet *v = C->node_arena()->contains(n) ? &new_space : &old_space;
2141 // Check for visited in the proper space. Numberings are not unique
2142 // across spaces so we need a separate VectorSet for each space.
2143 if( v->test_set(n->_idx) ) return;
2144
2145 if (n->is_Con() && n->bottom_type() == Type::TOP) {
2146 if (C->cached_top_node() == NULL)
2147 C->set_cached_top_node((Node*)n);
2148 assert(C->cached_top_node() == n, "TOP node must be unique");
2149 }
2150
2151 for( uint i = 0; i < n->len(); i++ ) {
2152 Node *x = n->in(i);
2153 if (!x || x->is_top()) continue;
2154
2155 // Verify my input has a def-use edge to me
2156 if (true /*VerifyDefUse*/) {
2157 // Count use-def edges from n to x
2158 int cnt = 0;
2159 for( uint j = 0; j < n->len(); j++ )
2160 if( n->in(j) == x )
2161 cnt++;
2162 // Count def-use edges from x to n
2163 uint max = x->_outcnt;
2164 for( uint k = 0; k < max; k++ )
2165 if (x->_out[k] == n)
2166 cnt--;
2167 assert( cnt == 0, "mismatched def-use edge counts" );
2168 }
2169
2170 verify_recur(x, verify_depth, old_space, new_space);
2171 }
2172
2173 }
2174
2175 //------------------------------verify-----------------------------------------
2176 // Check Def-Use info for my subgraph
2177 void Node::verify() const {
2178 Compile* C = Compile::current();
2179 Node* old_top = C->cached_top_node();
2180 ResourceMark rm;
2181 ResourceArea *area = Thread::current()->resource_area();
2182 VectorSet old_space(area), new_space(area);
2183 verify_recur(this, -1, old_space, new_space);
2184 C->set_cached_top_node(old_top);
2185 }
2186 #endif
2187
2188
2189 //------------------------------walk-------------------------------------------
2190 // Graph walk, with both pre-order and post-order functions
2191 void Node::walk(NFunc pre, NFunc post, void *env) {
2192 VectorSet visited(Thread::current()->resource_area()); // Setup for local walk
2193 walk_(pre, post, env, visited);
2194 }
2195
2196 void Node::walk_(NFunc pre, NFunc post, void *env, VectorSet &visited) {
2197 if( visited.test_set(_idx) ) return;
2198 pre(*this,env); // Call the pre-order walk function
2199 for( uint i=0; i<_max; i++ )
2200 if( in(i) ) // Input exists and is not walked?
2201 in(i)->walk_(pre,post,env,visited); // Walk it with pre & post functions
2202 post(*this,env); // Call the post-order walk function
2203 }
2204
2205 void Node::nop(Node &, void*) {}
2206
2207 //------------------------------Registers--------------------------------------
2208 // Do we Match on this edge index or not? Generally false for Control
2209 // and true for everything else. Weird for calls & returns.
2210 uint Node::match_edge(uint idx) const {
2211 return idx; // True for other than index 0 (control)
2212 }
2213
2214 static RegMask _not_used_at_all;
2215 // Register classes are defined for specific machines
2216 const RegMask &Node::out_RegMask() const {
2217 ShouldNotCallThis();
2218 return _not_used_at_all;
2219 }
2220
2221 const RegMask &Node::in_RegMask(uint) const {
2222 ShouldNotCallThis();
2223 return _not_used_at_all;
2224 }
2225
2226 //=============================================================================
2227 //-----------------------------------------------------------------------------
2228 void Node_Array::reset( Arena *new_arena ) {
2229 _a->Afree(_nodes,_max*sizeof(Node*));
2230 _max = 0;
2231 _nodes = NULL;
2232 _a = new_arena;
2233 }
2234
2235 //------------------------------clear------------------------------------------
2236 // Clear all entries in _nodes to NULL but keep storage
2237 void Node_Array::clear() {
2238 Copy::zero_to_bytes( _nodes, _max*sizeof(Node*) );
2239 }
2240
2241 //-----------------------------------------------------------------------------
2242 void Node_Array::grow( uint i ) {
2243 if( !_max ) {
2244 _max = 1;
2245 _nodes = (Node**)_a->Amalloc( _max * sizeof(Node*) );
2246 _nodes[0] = NULL;
2247 }
2248 uint old = _max;
2249 while( i >= _max ) _max <<= 1; // Double to fit
2250 _nodes = (Node**)_a->Arealloc( _nodes, old*sizeof(Node*),_max*sizeof(Node*));
2251 Copy::zero_to_bytes( &_nodes[old], (_max-old)*sizeof(Node*) );
2252 }
2253
2254 //-----------------------------------------------------------------------------
2255 void Node_Array::insert( uint i, Node *n ) {
2256 if( _nodes[_max-1] ) grow(_max); // Get more space if full
2257 Copy::conjoint_words_to_higher((HeapWord*)&_nodes[i], (HeapWord*)&_nodes[i+1], ((_max-i-1)*sizeof(Node*)));
2258 _nodes[i] = n;
2259 }
2260
2261 //-----------------------------------------------------------------------------
2262 void Node_Array::remove( uint i ) {
2263 Copy::conjoint_words_to_lower((HeapWord*)&_nodes[i+1], (HeapWord*)&_nodes[i], ((_max-i-1)*sizeof(Node*)));
2264 _nodes[_max-1] = NULL;
2265 }
2266
2267 //-----------------------------------------------------------------------------
2268 void Node_Array::sort( C_sort_func_t func) {
2269 qsort( _nodes, _max, sizeof( Node* ), func );
2270 }
2271
2272 //-----------------------------------------------------------------------------
2273 void Node_Array::dump() const {
2274 #ifndef PRODUCT
2275 for( uint i = 0; i < _max; i++ ) {
2276 Node *nn = _nodes[i];
2277 if( nn != NULL ) {
2278 tty->print("%5d--> ",i); nn->dump();
2279 }
2280 }
2281 #endif
2282 }
2283
2284 //--------------------------is_iteratively_computed------------------------------
2285 // Operation appears to be iteratively computed (such as an induction variable)
2286 // It is possible for this operation to return false for a loop-varying
2287 // value, if it appears (by local graph inspection) to be computed by a simple conditional.
2288 bool Node::is_iteratively_computed() {
2289 if (ideal_reg()) { // does operation have a result register?
2290 for (uint i = 1; i < req(); i++) {
2291 Node* n = in(i);
2292 if (n != NULL && n->is_Phi()) {
2293 for (uint j = 1; j < n->req(); j++) {
2294 if (n->in(j) == this) {
2295 return true;
2296 }
2297 }
2298 }
2299 }
2300 }
2301 return false;
2302 }
2303
2304 //--------------------------find_similar------------------------------
2305 // Return a node with opcode "opc" and same inputs as "this" if one can
2306 // be found; Otherwise return NULL;
2307 Node* Node::find_similar(int opc) {
2308 if (req() >= 2) {
2309 Node* def = in(1);
2310 if (def && def->outcnt() >= 2) {
2311 for (DUIterator_Fast dmax, i = def->fast_outs(dmax); i < dmax; i++) {
2312 Node* use = def->fast_out(i);
2313 if (use != this &&
2314 use->Opcode() == opc &&
2315 use->req() == req()) {
2316 uint j;
2317 for (j = 0; j < use->req(); j++) {
2318 if (use->in(j) != in(j)) {
2319 break;
2320 }
2321 }
2322 if (j == use->req()) {
2323 return use;
2324 }
2325 }
2326 }
2327 }
2328 }
2329 return NULL;
2330 }
2331
2332
2333 //--------------------------unique_ctrl_out------------------------------
2334 // Return the unique control out if only one. Null if none or more than one.
2335 Node* Node::unique_ctrl_out() const {
2336 Node* found = NULL;
2337 for (uint i = 0; i < outcnt(); i++) {
2338 Node* use = raw_out(i);
2339 if (use->is_CFG() && use != this) {
2340 if (found != NULL) return NULL;
2341 found = use;
2342 }
2343 }
2344 return found;
2345 }
2346
2347 void Node::ensure_control_or_add_prec(Node* c) {
2348 if (in(0) == NULL) {
2349 set_req(0, c);
2350 } else if (in(0) != c) {
2351 add_prec(c);
2352 }
2353 }
2354
2355 //=============================================================================
2356 //------------------------------yank-------------------------------------------
2357 // Find and remove
2358 void Node_List::yank( Node *n ) {
2359 uint i;
2360 for( i = 0; i < _cnt; i++ )
2361 if( _nodes[i] == n )
2362 break;
2363
2364 if( i < _cnt )
2365 _nodes[i] = _nodes[--_cnt];
2366 }
2367
2368 //------------------------------dump-------------------------------------------
2369 void Node_List::dump() const {
2370 #ifndef PRODUCT
2371 for( uint i = 0; i < _cnt; i++ )
2372 if( _nodes[i] ) {
2373 tty->print("%5d--> ",i);
2374 _nodes[i]->dump();
2375 }
2376 #endif
2377 }
2378
2379 void Node_List::dump_simple() const {
2380 #ifndef PRODUCT
2381 for( uint i = 0; i < _cnt; i++ )
2382 if( _nodes[i] ) {
2383 tty->print(" %d", _nodes[i]->_idx);
2384 } else {
2385 tty->print(" NULL");
2386 }
2387 #endif
2388 }
2389
2390 //=============================================================================
2391 //------------------------------remove-----------------------------------------
2392 void Unique_Node_List::remove( Node *n ) {
2393 if( _in_worklist[n->_idx] ) {
2394 for( uint i = 0; i < size(); i++ )
2395 if( _nodes[i] == n ) {
2396 map(i,Node_List::pop());
2397 _in_worklist >>= n->_idx;
2398 return;
2399 }
2400 ShouldNotReachHere();
2401 }
2402 }
2403
2404 //-----------------------remove_useless_nodes----------------------------------
2405 // Remove useless nodes from worklist
2406 void Unique_Node_List::remove_useless_nodes(VectorSet &useful) {
2407
2408 for( uint i = 0; i < size(); ++i ) {
2409 Node *n = at(i);
2410 assert( n != NULL, "Did not expect null entries in worklist");
2411 if( ! useful.test(n->_idx) ) {
2412 _in_worklist >>= n->_idx;
2413 map(i,Node_List::pop());
2414 // Node *replacement = Node_List::pop();
2415 // if( i != size() ) { // Check if removing last entry
2416 // _nodes[i] = replacement;
2417 // }
2418 --i; // Visit popped node
2419 // If it was last entry, loop terminates since size() was also reduced
2420 }
2421 }
2422 }
2423
2424 //=============================================================================
2425 void Node_Stack::grow() {
2426 size_t old_top = pointer_delta(_inode_top,_inodes,sizeof(INode)); // save _top
2427 size_t old_max = pointer_delta(_inode_max,_inodes,sizeof(INode));
2428 size_t max = old_max << 1; // max * 2
2429 _inodes = REALLOC_ARENA_ARRAY(_a, INode, _inodes, old_max, max);
2430 _inode_max = _inodes + max;
2431 _inode_top = _inodes + old_top; // restore _top
2432 }
2433
2434 // Node_Stack is used to map nodes.
2435 Node* Node_Stack::find(uint idx) const {
2436 uint sz = size();
2437 for (uint i=0; i < sz; i++) {
2438 if (idx == index_at(i) )
2439 return node_at(i);
2440 }
2441 return NULL;
2442 }
2443
2444 //=============================================================================
2445 uint TypeNode::size_of() const { return sizeof(*this); }
2446 #ifndef PRODUCT
2447 void TypeNode::dump_spec(outputStream *st) const {
2448 if( !Verbose && !WizardMode ) {
2449 // standard dump does this in Verbose and WizardMode
2450 st->print(" #"); _type->dump_on(st);
2451 }
2452 }
2453
2454 void TypeNode::dump_compact_spec(outputStream *st) const {
2455 st->print("#");
2456 _type->dump_on(st);
2457 }
2458 #endif
2459 uint TypeNode::hash() const {
2460 return Node::hash() + _type->hash();
2461 }
2462 bool TypeNode::cmp( const Node &n ) const
2463 { return !Type::cmp( _type, ((TypeNode&)n)._type ); }
2464 const Type *TypeNode::bottom_type() const { return _type; }
2465 const Type* TypeNode::Value(PhaseGVN* phase) const { return _type; }
2466
2467 //------------------------------ideal_reg--------------------------------------
2468 uint TypeNode::ideal_reg() const {
2469 return _type->ideal_reg();
2470 }