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 "libadt/vectset.hpp"
27 #include "memory/allocation.inline.hpp"
28 #include "opto/castnode.hpp"
29 #include "opto/cfgnode.hpp"
30 #include "opto/connode.hpp"
31 #include "opto/loopnode.hpp"
32 #include "opto/machnode.hpp"
33 #include "opto/matcher.hpp"
34 #include "opto/node.hpp"
35 #include "opto/opcodes.hpp"
36 #include "opto/regmask.hpp"
37 #include "opto/type.hpp"
38 #include "utilities/copy.hpp"
39
40 class RegMask;
41 // #include "phase.hpp"
42 class PhaseTransform;
43 class PhaseGVN;
44
45 // Arena we are currently building Nodes in
46 const uint Node::NotAMachineReg = 0xffff0000;
47
48 #ifndef PRODUCT
49 extern int nodes_created;
50 #endif
51 #ifdef __clang__
52 #pragma clang diagnostic push
53 #pragma GCC diagnostic ignored "-Wuninitialized"
54 #endif
55
56 #ifdef ASSERT
57
58 //-------------------------- construct_node------------------------------------
59 // Set a breakpoint here to identify where a particular node index is built.
60 void Node::verify_construction() {
61 _debug_orig = NULL;
62 int old_debug_idx = Compile::debug_idx();
63 int new_debug_idx = old_debug_idx+1;
64 if (new_debug_idx > 0) {
65 // Arrange that the lowest five decimal digits of _debug_idx
66 // will repeat those of _idx. In case this is somehow pathological,
67 // we continue to assign negative numbers (!) consecutively.
68 const int mod = 100000;
69 int bump = (int)(_idx - new_debug_idx) % mod;
70 if (bump < 0) bump += mod;
71 assert(bump >= 0 && bump < mod, "");
72 new_debug_idx += bump;
73 }
74 Compile::set_debug_idx(new_debug_idx);
75 set_debug_idx( new_debug_idx );
76 assert(Compile::current()->unique() < (INT_MAX - 1), "Node limit exceeded INT_MAX");
77 assert(Compile::current()->live_nodes() < Compile::current()->max_node_limit(), "Live Node limit exceeded limit");
78 if (BreakAtNode != 0 && (_debug_idx == BreakAtNode || (int)_idx == BreakAtNode)) {
79 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=%d", _idx, _debug_idx);
80 BREAKPOINT;
81 }
82 #if OPTO_DU_ITERATOR_ASSERT
83 _last_del = NULL;
84 _del_tick = 0;
85 #endif
86 _hash_lock = 0;
87 }
88
89
90 // #ifdef ASSERT ...
91
92 #if OPTO_DU_ITERATOR_ASSERT
93 void DUIterator_Common::sample(const Node* node) {
94 _vdui = VerifyDUIterators;
95 _node = node;
96 _outcnt = node->_outcnt;
97 _del_tick = node->_del_tick;
98 _last = NULL;
99 }
100
101 void DUIterator_Common::verify(const Node* node, bool at_end_ok) {
102 assert(_node == node, "consistent iterator source");
103 assert(_del_tick == node->_del_tick, "no unexpected deletions allowed");
104 }
105
106 void DUIterator_Common::verify_resync() {
107 // Ensure that the loop body has just deleted the last guy produced.
108 const Node* node = _node;
109 // Ensure that at least one copy of the last-seen edge was deleted.
110 // Note: It is OK to delete multiple copies of the last-seen edge.
111 // Unfortunately, we have no way to verify that all the deletions delete
112 // that same edge. On this point we must use the Honor System.
113 assert(node->_del_tick >= _del_tick+1, "must have deleted an edge");
114 assert(node->_last_del == _last, "must have deleted the edge just produced");
115 // We liked this deletion, so accept the resulting outcnt and tick.
116 _outcnt = node->_outcnt;
117 _del_tick = node->_del_tick;
118 }
119
120 void DUIterator_Common::reset(const DUIterator_Common& that) {
121 if (this == &that) return; // ignore assignment to self
122 if (!_vdui) {
123 // We need to initialize everything, overwriting garbage values.
124 _last = that._last;
125 _vdui = that._vdui;
126 }
127 // Note: It is legal (though odd) for an iterator over some node x
128 // to be reassigned to iterate over another node y. Some doubly-nested
129 // progress loops depend on being able to do this.
130 const Node* node = that._node;
131 // Re-initialize everything, except _last.
132 _node = node;
133 _outcnt = node->_outcnt;
134 _del_tick = node->_del_tick;
135 }
136
137 void DUIterator::sample(const Node* node) {
138 DUIterator_Common::sample(node); // Initialize the assertion data.
139 _refresh_tick = 0; // No refreshes have happened, as yet.
140 }
141
142 void DUIterator::verify(const Node* node, bool at_end_ok) {
143 DUIterator_Common::verify(node, at_end_ok);
144 assert(_idx < node->_outcnt + (uint)at_end_ok, "idx in range");
145 }
146
147 void DUIterator::verify_increment() {
148 if (_refresh_tick & 1) {
149 // We have refreshed the index during this loop.
150 // Fix up _idx to meet asserts.
151 if (_idx > _outcnt) _idx = _outcnt;
152 }
153 verify(_node, true);
154 }
155
156 void DUIterator::verify_resync() {
157 // Note: We do not assert on _outcnt, because insertions are OK here.
158 DUIterator_Common::verify_resync();
159 // Make sure we are still in sync, possibly with no more out-edges:
160 verify(_node, true);
161 }
162
163 void DUIterator::reset(const DUIterator& that) {
164 if (this == &that) return; // self assignment is always a no-op
165 assert(that._refresh_tick == 0, "assign only the result of Node::outs()");
166 assert(that._idx == 0, "assign only the result of Node::outs()");
167 assert(_idx == that._idx, "already assigned _idx");
168 if (!_vdui) {
169 // We need to initialize everything, overwriting garbage values.
170 sample(that._node);
171 } else {
172 DUIterator_Common::reset(that);
173 if (_refresh_tick & 1) {
174 _refresh_tick++; // Clear the "was refreshed" flag.
175 }
176 assert(_refresh_tick < 2*100000, "DU iteration must converge quickly");
177 }
178 }
179
180 void DUIterator::refresh() {
181 DUIterator_Common::sample(_node); // Re-fetch assertion data.
182 _refresh_tick |= 1; // Set the "was refreshed" flag.
183 }
184
185 void DUIterator::verify_finish() {
186 // If the loop has killed the node, do not require it to re-run.
187 if (_node->_outcnt == 0) _refresh_tick &= ~1;
188 // If this assert triggers, it means that a loop used refresh_out_pos
189 // to re-synch an iteration index, but the loop did not correctly
190 // re-run itself, using a "while (progress)" construct.
191 // This iterator enforces the rule that you must keep trying the loop
192 // until it "runs clean" without any need for refreshing.
193 assert(!(_refresh_tick & 1), "the loop must run once with no refreshing");
194 }
195
196
197 void DUIterator_Fast::verify(const Node* node, bool at_end_ok) {
198 DUIterator_Common::verify(node, at_end_ok);
199 Node** out = node->_out;
200 uint cnt = node->_outcnt;
201 assert(cnt == _outcnt, "no insertions allowed");
202 assert(_outp >= out && _outp <= out + cnt - !at_end_ok, "outp in range");
203 // This last check is carefully designed to work for NO_OUT_ARRAY.
204 }
205
206 void DUIterator_Fast::verify_limit() {
207 const Node* node = _node;
208 verify(node, true);
209 assert(_outp == node->_out + node->_outcnt, "limit still correct");
210 }
211
212 void DUIterator_Fast::verify_resync() {
213 const Node* node = _node;
214 if (_outp == node->_out + _outcnt) {
215 // Note that the limit imax, not the pointer i, gets updated with the
216 // exact count of deletions. (For the pointer it's always "--i".)
217 assert(node->_outcnt+node->_del_tick == _outcnt+_del_tick, "no insertions allowed with deletion(s)");
218 // This is a limit pointer, with a name like "imax".
219 // Fudge the _last field so that the common assert will be happy.
220 _last = (Node*) node->_last_del;
221 DUIterator_Common::verify_resync();
222 } else {
223 assert(node->_outcnt < _outcnt, "no insertions allowed with deletion(s)");
224 // A normal internal pointer.
225 DUIterator_Common::verify_resync();
226 // Make sure we are still in sync, possibly with no more out-edges:
227 verify(node, true);
228 }
229 }
230
231 void DUIterator_Fast::verify_relimit(uint n) {
232 const Node* node = _node;
233 assert((int)n > 0, "use imax -= n only with a positive count");
234 // This must be a limit pointer, with a name like "imax".
235 assert(_outp == node->_out + node->_outcnt, "apply -= only to a limit (imax)");
236 // The reported number of deletions must match what the node saw.
237 assert(node->_del_tick == _del_tick + n, "must have deleted n edges");
238 // Fudge the _last field so that the common assert will be happy.
239 _last = (Node*) node->_last_del;
240 DUIterator_Common::verify_resync();
241 }
242
243 void DUIterator_Fast::reset(const DUIterator_Fast& that) {
244 assert(_outp == that._outp, "already assigned _outp");
245 DUIterator_Common::reset(that);
246 }
247
248 void DUIterator_Last::verify(const Node* node, bool at_end_ok) {
249 // at_end_ok means the _outp is allowed to underflow by 1
250 _outp += at_end_ok;
251 DUIterator_Fast::verify(node, at_end_ok); // check _del_tick, etc.
252 _outp -= at_end_ok;
253 assert(_outp == (node->_out + node->_outcnt) - 1, "pointer must point to end of nodes");
254 }
255
256 void DUIterator_Last::verify_limit() {
257 // Do not require the limit address to be resynched.
258 //verify(node, true);
259 assert(_outp == _node->_out, "limit still correct");
260 }
261
262 void DUIterator_Last::verify_step(uint num_edges) {
263 assert((int)num_edges > 0, "need non-zero edge count for loop progress");
264 _outcnt -= num_edges;
265 _del_tick += num_edges;
266 // Make sure we are still in sync, possibly with no more out-edges:
267 const Node* node = _node;
268 verify(node, true);
269 assert(node->_last_del == _last, "must have deleted the edge just produced");
270 }
271
272 #endif //OPTO_DU_ITERATOR_ASSERT
273
274
275 #endif //ASSERT
276
277
278 // This constant used to initialize _out may be any non-null value.
279 // The value NULL is reserved for the top node only.
280 #define NO_OUT_ARRAY ((Node**)-1)
281
282 // Out-of-line code from node constructors.
283 // Executed only when extra debug info. is being passed around.
284 static void init_node_notes(Compile* C, int idx, Node_Notes* nn) {
285 C->set_node_notes_at(idx, nn);
286 }
287
288 // Shared initialization code.
289 inline int Node::Init(int req) {
290 Compile* C = Compile::current();
291 int idx = C->next_unique();
292
293 // Allocate memory for the necessary number of edges.
294 if (req > 0) {
295 // Allocate space for _in array to have double alignment.
296 _in = (Node **) ((char *) (C->node_arena()->Amalloc_D(req * sizeof(void*))));
297 #ifdef ASSERT
298 _in[req-1] = this; // magic cookie for assertion check
299 #endif
300 }
301 // If there are default notes floating around, capture them:
302 Node_Notes* nn = C->default_node_notes();
303 if (nn != NULL) init_node_notes(C, idx, nn);
304
305 // Note: At this point, C is dead,
306 // and we begin to initialize the new Node.
307
308 _cnt = _max = req;
309 _outcnt = _outmax = 0;
310 _class_id = Class_Node;
311 _flags = 0;
312 _out = NO_OUT_ARRAY;
313 return idx;
314 }
315
316 //------------------------------Node-------------------------------------------
317 // Create a Node, with a given number of required edges.
318 Node::Node(uint req)
319 : _idx(Init(req))
320 #ifdef ASSERT
321 , _parse_idx(_idx)
322 #endif
323 {
324 assert( req < Compile::current()->max_node_limit() - NodeLimitFudgeFactor, "Input limit exceeded" );
325 debug_only( verify_construction() );
326 NOT_PRODUCT(nodes_created++);
327 if (req == 0) {
328 assert( _in == (Node**)this, "Must not pass arg count to 'new'" );
329 _in = NULL;
330 } else {
331 assert( _in[req-1] == this, "Must pass arg count to 'new'" );
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 we allocated space for input array already
349 assert( _in[0] == this, "Must pass arg count to 'new'" );
350 assert( is_not_dead(n0), "can not use dead node");
351 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
352 }
353
354 //------------------------------Node-------------------------------------------
355 Node::Node(Node *n0, Node *n1)
356 : _idx(Init(2))
357 #ifdef ASSERT
358 , _parse_idx(_idx)
359 #endif
360 {
361 debug_only( verify_construction() );
362 NOT_PRODUCT(nodes_created++);
363 // Assert we allocated space for input array already
364 assert( _in[1] == this, "Must pass arg count to 'new'" );
365 assert( is_not_dead(n0), "can not use dead node");
366 assert( is_not_dead(n1), "can not use dead node");
367 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
368 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
369 }
370
371 //------------------------------Node-------------------------------------------
372 Node::Node(Node *n0, Node *n1, Node *n2)
373 : _idx(Init(3))
374 #ifdef ASSERT
375 , _parse_idx(_idx)
376 #endif
377 {
378 debug_only( verify_construction() );
379 NOT_PRODUCT(nodes_created++);
380 // Assert we allocated space for input array already
381 assert( _in[2] == this, "Must pass arg count to 'new'" );
382 assert( is_not_dead(n0), "can not use dead node");
383 assert( is_not_dead(n1), "can not use dead node");
384 assert( is_not_dead(n2), "can not use dead node");
385 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
386 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
387 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
388 }
389
390 //------------------------------Node-------------------------------------------
391 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3)
392 : _idx(Init(4))
393 #ifdef ASSERT
394 , _parse_idx(_idx)
395 #endif
396 {
397 debug_only( verify_construction() );
398 NOT_PRODUCT(nodes_created++);
399 // Assert we allocated space for input array already
400 assert( _in[3] == this, "Must pass arg count to 'new'" );
401 assert( is_not_dead(n0), "can not use dead node");
402 assert( is_not_dead(n1), "can not use dead node");
403 assert( is_not_dead(n2), "can not use dead node");
404 assert( is_not_dead(n3), "can not use dead node");
405 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
406 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
407 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
408 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
409 }
410
411 //------------------------------Node-------------------------------------------
412 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3, Node *n4)
413 : _idx(Init(5))
414 #ifdef ASSERT
415 , _parse_idx(_idx)
416 #endif
417 {
418 debug_only( verify_construction() );
419 NOT_PRODUCT(nodes_created++);
420 // Assert we allocated space for input array already
421 assert( _in[4] == this, "Must pass arg count to 'new'" );
422 assert( is_not_dead(n0), "can not use dead node");
423 assert( is_not_dead(n1), "can not use dead node");
424 assert( is_not_dead(n2), "can not use dead node");
425 assert( is_not_dead(n3), "can not use dead node");
426 assert( is_not_dead(n4), "can not use dead node");
427 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
428 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
429 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
430 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
431 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this);
432 }
433
434 //------------------------------Node-------------------------------------------
435 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3,
436 Node *n4, Node *n5)
437 : _idx(Init(6))
438 #ifdef ASSERT
439 , _parse_idx(_idx)
440 #endif
441 {
442 debug_only( verify_construction() );
443 NOT_PRODUCT(nodes_created++);
444 // Assert we allocated space for input array already
445 assert( _in[5] == this, "Must pass arg count to 'new'" );
446 assert( is_not_dead(n0), "can not use dead node");
447 assert( is_not_dead(n1), "can not use dead node");
448 assert( is_not_dead(n2), "can not use dead node");
449 assert( is_not_dead(n3), "can not use dead node");
450 assert( is_not_dead(n4), "can not use dead node");
451 assert( is_not_dead(n5), "can not use dead node");
452 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
453 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
454 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
455 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
456 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this);
457 _in[5] = n5; if (n5 != NULL) n5->add_out((Node *)this);
458 }
459
460 //------------------------------Node-------------------------------------------
461 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3,
462 Node *n4, Node *n5, Node *n6)
463 : _idx(Init(7))
464 #ifdef ASSERT
465 , _parse_idx(_idx)
466 #endif
467 {
468 debug_only( verify_construction() );
469 NOT_PRODUCT(nodes_created++);
470 // Assert we allocated space for input array already
471 assert( _in[6] == this, "Must pass arg count to 'new'" );
472 assert( is_not_dead(n0), "can not use dead node");
473 assert( is_not_dead(n1), "can not use dead node");
474 assert( is_not_dead(n2), "can not use dead node");
475 assert( is_not_dead(n3), "can not use dead node");
476 assert( is_not_dead(n4), "can not use dead node");
477 assert( is_not_dead(n5), "can not use dead node");
478 assert( is_not_dead(n6), "can not use dead node");
479 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this);
480 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this);
481 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this);
482 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this);
483 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this);
484 _in[5] = n5; if (n5 != NULL) n5->add_out((Node *)this);
485 _in[6] = n6; if (n6 != NULL) n6->add_out((Node *)this);
486 }
487
488 #ifdef __clang__
489 #pragma clang diagnostic pop
490 #endif
491
492
493 //------------------------------clone------------------------------------------
494 // Clone a Node.
495 Node *Node::clone() const {
496 Compile* C = Compile::current();
497 uint s = size_of(); // Size of inherited Node
498 Node *n = (Node*)C->node_arena()->Amalloc_D(size_of() + _max*sizeof(Node*));
499 Copy::conjoint_words_to_lower((HeapWord*)this, (HeapWord*)n, s);
500 // Set the new input pointer array
501 n->_in = (Node**)(((char*)n)+s);
502 // Cannot share the old output pointer array, so kill it
503 n->_out = NO_OUT_ARRAY;
504 // And reset the counters to 0
505 n->_outcnt = 0;
506 n->_outmax = 0;
507 // Unlock this guy, since he is not in any hash table.
508 debug_only(n->_hash_lock = 0);
509 // Walk the old node's input list to duplicate its edges
510 uint i;
511 for( i = 0; i < len(); i++ ) {
512 Node *x = in(i);
513 n->_in[i] = x;
514 if (x != NULL) x->add_out(n);
515 }
516 if (is_macro())
517 C->add_macro_node(n);
518 if (is_expensive())
519 C->add_expensive_node(n);
520 #ifdef _LP64
521 // If the cloned node is a range check dependent CastII, add it to the list.
522 CastIINode* cast = n->isa_CastII();
523 if (cast != NULL && cast->has_range_check()) {
524 C->add_range_check_cast(cast);
525 }
526 #endif
527
528 n->set_idx(C->next_unique()); // Get new unique index as well
529 debug_only( n->verify_construction() );
530 NOT_PRODUCT(nodes_created++);
531 // Do not patch over the debug_idx of a clone, because it makes it
532 // impossible to break on the clone's moment of creation.
533 //debug_only( n->set_debug_idx( debug_idx() ) );
534
535 C->copy_node_notes_to(n, (Node*) this);
536
537 // MachNode clone
538 uint nopnds;
539 if (this->is_Mach() && (nopnds = this->as_Mach()->num_opnds()) > 0) {
540 MachNode *mach = n->as_Mach();
541 MachNode *mthis = this->as_Mach();
542 // Get address of _opnd_array.
543 // It should be the same offset since it is the clone of this node.
544 MachOper **from = mthis->_opnds;
545 MachOper **to = (MachOper **)((size_t)(&mach->_opnds) +
546 pointer_delta((const void*)from,
547 (const void*)(&mthis->_opnds), 1));
548 mach->_opnds = to;
549 for ( uint i = 0; i < nopnds; ++i ) {
550 to[i] = from[i]->clone();
551 }
552 }
553 // cloning CallNode may need to clone JVMState
554 if (n->is_Call()) {
555 n->as_Call()->clone_jvms(C);
556 }
557 if (n->is_SafePoint()) {
558 n->as_SafePoint()->clone_replaced_nodes();
559 }
560 return n; // Return the clone
561 }
562
563 //---------------------------setup_is_top--------------------------------------
564 // Call this when changing the top node, to reassert the invariants
565 // required by Node::is_top. See Compile::set_cached_top_node.
566 void Node::setup_is_top() {
567 if (this == (Node*)Compile::current()->top()) {
568 // This node has just become top. Kill its out array.
569 _outcnt = _outmax = 0;
570 _out = NULL; // marker value for top
571 assert(is_top(), "must be top");
572 } else {
573 if (_out == NULL) _out = NO_OUT_ARRAY;
574 assert(!is_top(), "must not be top");
575 }
576 }
577
578
579 //------------------------------~Node------------------------------------------
580 // Fancy destructor; eagerly attempt to reclaim Node numberings and storage
581 extern int reclaim_idx ;
582 extern int reclaim_in ;
583 extern int reclaim_node;
584 void Node::destruct() {
585 // Eagerly reclaim unique Node numberings
586 Compile* compile = Compile::current();
587 if ((uint)_idx+1 == compile->unique()) {
588 compile->set_unique(compile->unique()-1);
589 #ifdef ASSERT
590 reclaim_idx++;
591 #endif
592 }
593 // Clear debug info:
594 Node_Notes* nn = compile->node_notes_at(_idx);
595 if (nn != NULL) nn->clear();
596 // Walk the input array, freeing the corresponding output edges
597 _cnt = _max; // forget req/prec distinction
598 uint i;
599 for( i = 0; i < _max; i++ ) {
600 set_req(i, NULL);
601 //assert(def->out(def->outcnt()-1) == (Node *)this,"bad def-use hacking in reclaim");
602 }
603 assert(outcnt() == 0, "deleting a node must not leave a dangling use");
604 // See if the input array was allocated just prior to the object
605 int edge_size = _max*sizeof(void*);
606 int out_edge_size = _outmax*sizeof(void*);
607 char *edge_end = ((char*)_in) + edge_size;
608 char *out_array = (char*)(_out == NO_OUT_ARRAY? NULL: _out);
609 char *out_edge_end = out_array + out_edge_size;
610 int node_size = size_of();
611
612 // Free the output edge array
613 if (out_edge_size > 0) {
614 #ifdef ASSERT
615 if( out_edge_end == compile->node_arena()->hwm() )
616 reclaim_in += out_edge_size; // count reclaimed out edges with in edges
617 #endif
618 compile->node_arena()->Afree(out_array, out_edge_size);
619 }
620
621 // Free the input edge array and the node itself
622 if( edge_end == (char*)this ) {
623 #ifdef ASSERT
624 if( edge_end+node_size == compile->node_arena()->hwm() ) {
625 reclaim_in += edge_size;
626 reclaim_node+= node_size;
627 }
628 #else
629 // It was; free the input array and object all in one hit
630 compile->node_arena()->Afree(_in,edge_size+node_size);
631 #endif
632 } else {
633
634 // Free just the input array
635 #ifdef ASSERT
636 if( edge_end == compile->node_arena()->hwm() )
637 reclaim_in += edge_size;
638 #endif
639 compile->node_arena()->Afree(_in,edge_size);
640
641 // Free just the object
642 #ifdef ASSERT
643 if( ((char*)this) + node_size == compile->node_arena()->hwm() )
644 reclaim_node+= node_size;
645 #else
646 compile->node_arena()->Afree(this,node_size);
647 #endif
648 }
649 if (is_macro()) {
650 compile->remove_macro_node(this);
651 }
652 if (is_expensive()) {
653 compile->remove_expensive_node(this);
654 }
655 #ifdef _LP64
656 CastIINode* cast = isa_CastII();
657 if (cast != NULL && cast->has_range_check()) {
658 compile->remove_range_check_cast(cast);
659 }
660 #endif
661
662 if (is_SafePoint()) {
663 as_SafePoint()->delete_replaced_nodes();
664 }
665 #ifdef ASSERT
666 // We will not actually delete the storage, but we'll make the node unusable.
667 *(address*)this = badAddress; // smash the C++ vtbl, probably
668 _in = _out = (Node**) badAddress;
669 _max = _cnt = _outmax = _outcnt = 0;
670 compile->remove_modified_node(this);
671 #endif
672 }
673
674 //------------------------------grow-------------------------------------------
675 // Grow the input array, making space for more edges
676 void Node::grow( uint len ) {
677 Arena* arena = Compile::current()->node_arena();
678 uint new_max = _max;
679 if( new_max == 0 ) {
680 _max = 4;
681 _in = (Node**)arena->Amalloc(4*sizeof(Node*));
682 Node** to = _in;
683 to[0] = NULL;
684 to[1] = NULL;
685 to[2] = NULL;
686 to[3] = NULL;
687 return;
688 }
689 while( new_max <= len ) new_max <<= 1; // Find next power-of-2
690 // Trimming to limit allows a uint8 to handle up to 255 edges.
691 // Previously I was using only powers-of-2 which peaked at 128 edges.
692 //if( new_max >= limit ) new_max = limit-1;
693 _in = (Node**)arena->Arealloc(_in, _max*sizeof(Node*), new_max*sizeof(Node*));
694 Copy::zero_to_bytes(&_in[_max], (new_max-_max)*sizeof(Node*)); // NULL all new space
695 _max = new_max; // Record new max length
696 // This assertion makes sure that Node::_max is wide enough to
697 // represent the numerical value of new_max.
698 assert(_max == new_max && _max > len, "int width of _max is too small");
699 }
700
701 //-----------------------------out_grow----------------------------------------
702 // Grow the input array, making space for more edges
703 void Node::out_grow( uint len ) {
704 assert(!is_top(), "cannot grow a top node's out array");
705 Arena* arena = Compile::current()->node_arena();
706 uint new_max = _outmax;
707 if( new_max == 0 ) {
708 _outmax = 4;
709 _out = (Node **)arena->Amalloc(4*sizeof(Node*));
710 return;
711 }
712 while( new_max <= len ) new_max <<= 1; // Find next power-of-2
713 // Trimming to limit allows a uint8 to handle up to 255 edges.
714 // Previously I was using only powers-of-2 which peaked at 128 edges.
715 //if( new_max >= limit ) new_max = limit-1;
716 assert(_out != NULL && _out != NO_OUT_ARRAY, "out must have sensible value");
717 _out = (Node**)arena->Arealloc(_out,_outmax*sizeof(Node*),new_max*sizeof(Node*));
718 //Copy::zero_to_bytes(&_out[_outmax], (new_max-_outmax)*sizeof(Node*)); // NULL all new space
719 _outmax = new_max; // Record new max length
720 // This assertion makes sure that Node::_max is wide enough to
721 // represent the numerical value of new_max.
722 assert(_outmax == new_max && _outmax > len, "int width of _outmax is too small");
723 }
724
725 #ifdef ASSERT
726 //------------------------------is_dead----------------------------------------
727 bool Node::is_dead() const {
728 // Mach and pinch point nodes may look like dead.
729 if( is_top() || is_Mach() || (Opcode() == Op_Node && _outcnt > 0) )
730 return false;
731 for( uint i = 0; i < _max; i++ )
732 if( _in[i] != NULL )
733 return false;
734 dump();
735 return true;
736 }
737 #endif
738
739
740 //------------------------------is_unreachable---------------------------------
741 bool Node::is_unreachable(PhaseIterGVN &igvn) const {
742 assert(!is_Mach(), "doesn't work with MachNodes");
743 return outcnt() == 0 || igvn.type(this) == Type::TOP || in(0)->is_top();
744 }
745
746 //------------------------------add_req----------------------------------------
747 // Add a new required input at the end
748 void Node::add_req( Node *n ) {
749 assert( is_not_dead(n), "can not use dead node");
750
751 // Look to see if I can move precedence down one without reallocating
752 if( (_cnt >= _max) || (in(_max-1) != NULL) )
753 grow( _max+1 );
754
755 // Find a precedence edge to move
756 if( in(_cnt) != NULL ) { // Next precedence edge is busy?
757 uint i;
758 for( i=_cnt; i<_max; i++ )
759 if( in(i) == NULL ) // Find the NULL at end of prec edge list
760 break; // There must be one, since we grew the array
761 _in[i] = in(_cnt); // Move prec over, making space for req edge
762 }
763 _in[_cnt++] = n; // Stuff over old prec edge
764 if (n != NULL) n->add_out((Node *)this);
765 }
766
767 //---------------------------add_req_batch-------------------------------------
768 // Add a new required input at the end
769 void Node::add_req_batch( Node *n, uint m ) {
770 assert( is_not_dead(n), "can not use dead node");
771 // check various edge cases
772 if ((int)m <= 1) {
773 assert((int)m >= 0, "oob");
774 if (m != 0) add_req(n);
775 return;
776 }
777
778 // Look to see if I can move precedence down one without reallocating
779 if( (_cnt+m) > _max || _in[_max-m] )
780 grow( _max+m );
781
782 // Find a precedence edge to move
783 if( _in[_cnt] != NULL ) { // Next precedence edge is busy?
784 uint i;
785 for( i=_cnt; i<_max; i++ )
786 if( _in[i] == NULL ) // Find the NULL at end of prec edge list
787 break; // There must be one, since we grew the array
788 // Slide all the precs over by m positions (assume #prec << m).
789 Copy::conjoint_words_to_higher((HeapWord*)&_in[_cnt], (HeapWord*)&_in[_cnt+m], ((i-_cnt)*sizeof(Node*)));
790 }
791
792 // Stuff over the old prec edges
793 for(uint i=0; i<m; i++ ) {
794 _in[_cnt++] = n;
795 }
796
797 // Insert multiple out edges on the node.
798 if (n != NULL && !n->is_top()) {
799 for(uint i=0; i<m; i++ ) {
800 n->add_out((Node *)this);
801 }
802 }
803 }
804
805 //------------------------------del_req----------------------------------------
806 // Delete the required edge and compact the edge array
807 void Node::del_req( uint idx ) {
808 assert( idx < _cnt, "oob");
809 assert( !VerifyHashTableKeys || _hash_lock == 0,
810 "remove node from hash table before modifying it");
811 // First remove corresponding def-use edge
812 Node *n = in(idx);
813 if (n != NULL) n->del_out((Node *)this);
814 _in[idx] = in(--_cnt); // Compact the array
815 // Avoid spec violation: Gap in prec edges.
816 close_prec_gap_at(_cnt);
817 Compile::current()->record_modified_node(this);
818 }
819
820 //------------------------------del_req_ordered--------------------------------
821 // Delete the required edge and compact the edge array with preserved order
822 void Node::del_req_ordered( uint idx ) {
823 assert( idx < _cnt, "oob");
824 assert( !VerifyHashTableKeys || _hash_lock == 0,
825 "remove node from hash table before modifying it");
826 // First remove corresponding def-use edge
827 Node *n = in(idx);
828 if (n != NULL) n->del_out((Node *)this);
829 if (idx < --_cnt) { // Not last edge ?
830 Copy::conjoint_words_to_lower((HeapWord*)&_in[idx+1], (HeapWord*)&_in[idx], ((_cnt-idx)*sizeof(Node*)));
831 }
832 // Avoid spec violation: Gap in prec edges.
833 close_prec_gap_at(_cnt);
834 Compile::current()->record_modified_node(this);
835 }
836
837 //------------------------------ins_req----------------------------------------
838 // Insert a new required input at the end
839 void Node::ins_req( uint idx, Node *n ) {
840 assert( is_not_dead(n), "can not use dead node");
841 add_req(NULL); // Make space
842 assert( idx < _max, "Must have allocated enough space");
843 // Slide over
844 if(_cnt-idx-1 > 0) {
845 Copy::conjoint_words_to_higher((HeapWord*)&_in[idx], (HeapWord*)&_in[idx+1], ((_cnt-idx-1)*sizeof(Node*)));
846 }
847 _in[idx] = n; // Stuff over old required edge
848 if (n != NULL) n->add_out((Node *)this); // Add reciprocal def-use edge
849 }
850
851 //-----------------------------find_edge---------------------------------------
852 int Node::find_edge(Node* n) {
853 for (uint i = 0; i < len(); i++) {
854 if (_in[i] == n) return i;
855 }
856 return -1;
857 }
858
859 //----------------------------replace_edge-------------------------------------
860 int Node::replace_edge(Node* old, Node* neww) {
861 if (old == neww) return 0; // nothing to do
862 uint nrep = 0;
863 for (uint i = 0; i < len(); i++) {
864 if (in(i) == old) {
865 if (i < req()) {
866 set_req(i, neww);
867 } else {
868 assert(find_prec_edge(neww) == -1, "spec violation: duplicated prec edge (node %d -> %d)", _idx, neww->_idx);
869 set_prec(i, neww);
870 }
871 nrep++;
872 }
873 }
874 return nrep;
875 }
876
877 /**
878 * Replace input edges in the range pointing to 'old' node.
879 */
880 int Node::replace_edges_in_range(Node* old, Node* neww, int start, int end) {
881 if (old == neww) return 0; // nothing to do
882 uint nrep = 0;
883 for (int i = start; i < end; i++) {
884 if (in(i) == old) {
885 set_req(i, neww);
886 nrep++;
887 }
888 }
889 return nrep;
890 }
891
892 //-------------------------disconnect_inputs-----------------------------------
893 // NULL out all inputs to eliminate incoming Def-Use edges.
894 // Return the number of edges between 'n' and 'this'
895 int Node::disconnect_inputs(Node *n, Compile* C) {
896 int edges_to_n = 0;
897
898 uint cnt = req();
899 for( uint i = 0; i < cnt; ++i ) {
900 if( in(i) == 0 ) continue;
901 if( in(i) == n ) ++edges_to_n;
902 set_req(i, NULL);
903 }
904 // Remove precedence edges if any exist
905 // Note: Safepoints may have precedence edges, even during parsing
906 if( (req() != len()) && (in(req()) != NULL) ) {
907 uint max = len();
908 for( uint i = 0; i < max; ++i ) {
909 if( in(i) == 0 ) continue;
910 if( in(i) == n ) ++edges_to_n;
911 set_prec(i, NULL);
912 }
913 }
914
915 // Node::destruct requires all out edges be deleted first
916 // debug_only(destruct();) // no reuse benefit expected
917 if (edges_to_n == 0) {
918 C->record_dead_node(_idx);
919 }
920 return edges_to_n;
921 }
922
923 //-----------------------------uncast---------------------------------------
924 // %%% Temporary, until we sort out CheckCastPP vs. CastPP.
925 // Strip away casting. (It is depth-limited.)
926 Node* Node::uncast() const {
927 // Should be inline:
928 //return is_ConstraintCast() ? uncast_helper(this) : (Node*) this;
929 if (is_ConstraintCast())
930 return uncast_helper(this);
931 else
932 return (Node*) this;
933 }
934
935 // Find out of current node that matches opcode.
936 Node* Node::find_out_with(int opcode) {
937 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
938 Node* use = fast_out(i);
939 if (use->Opcode() == opcode) {
940 return use;
941 }
942 }
943 return NULL;
944 }
945
946 // Return true if the current node has an out that matches opcode.
947 bool Node::has_out_with(int opcode) {
948 return (find_out_with(opcode) != NULL);
949 }
950
951 // Return true if the current node has an out that matches any of the opcodes.
952 bool Node::has_out_with(int opcode1, int opcode2, int opcode3, int opcode4) {
953 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
954 int opcode = fast_out(i)->Opcode();
955 if (opcode == opcode1 || opcode == opcode2 || opcode == opcode3 || opcode == opcode4) {
956 return true;
957 }
958 }
959 return false;
960 }
961
962
963 //---------------------------uncast_helper-------------------------------------
964 Node* Node::uncast_helper(const Node* p) {
965 #ifdef ASSERT
966 uint depth_count = 0;
967 const Node* orig_p = p;
968 #endif
969
970 while (true) {
971 #ifdef ASSERT
972 if (depth_count >= K) {
973 orig_p->dump(4);
974 if (p != orig_p)
975 p->dump(1);
976 }
977 assert(depth_count++ < K, "infinite loop in Node::uncast_helper");
978 #endif
979 if (p == NULL || p->req() != 2) {
980 break;
981 } else if (p->is_ConstraintCast()) {
982 p = p->in(1);
983 } else {
984 break;
985 }
986 }
987 return (Node*) p;
988 }
989
990 //------------------------------add_prec---------------------------------------
991 // Add a new precedence input. Precedence inputs are unordered, with
992 // duplicates removed and NULLs packed down at the end.
993 void Node::add_prec( Node *n ) {
994 assert( is_not_dead(n), "can not use dead node");
995
996 // Check for NULL at end
997 if( _cnt >= _max || in(_max-1) )
998 grow( _max+1 );
999
1000 // Find a precedence edge to move
1001 uint i = _cnt;
1002 while( in(i) != NULL ) {
1003 if (in(i) == n) return; // Avoid spec violation: duplicated prec edge.
1004 i++;
1005 }
1006 _in[i] = n; // Stuff prec edge over NULL
1007 if ( n != NULL) n->add_out((Node *)this); // Add mirror edge
1008
1009 #ifdef ASSERT
1010 while ((++i)<_max) { assert(_in[i] == NULL, "spec violation: Gap in prec edges (node %d)", _idx); }
1011 #endif
1012 }
1013
1014 //------------------------------rm_prec----------------------------------------
1015 // Remove a precedence input. Precedence inputs are unordered, with
1016 // duplicates removed and NULLs packed down at the end.
1017 void Node::rm_prec( uint j ) {
1018 assert(j < _max, "oob: i=%d, _max=%d", j, _max);
1019 assert(j >= _cnt, "not a precedence edge");
1020 if (_in[j] == NULL) return; // Avoid spec violation: Gap in prec edges.
1021 _in[j]->del_out((Node *)this);
1022 close_prec_gap_at(j);
1023 }
1024
1025 //------------------------------size_of----------------------------------------
1026 uint Node::size_of() const { return sizeof(*this); }
1027
1028 //------------------------------ideal_reg--------------------------------------
1029 uint Node::ideal_reg() const { return 0; }
1030
1031 //------------------------------jvms-------------------------------------------
1032 JVMState* Node::jvms() const { return NULL; }
1033
1034 #ifdef ASSERT
1035 //------------------------------jvms-------------------------------------------
1036 bool Node::verify_jvms(const JVMState* using_jvms) const {
1037 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
1038 if (jvms == using_jvms) return true;
1039 }
1040 return false;
1041 }
1042
1043 //------------------------------init_NodeProperty------------------------------
1044 void Node::init_NodeProperty() {
1045 assert(_max_classes <= max_jushort, "too many NodeProperty classes");
1046 assert(_max_flags <= max_jushort, "too many NodeProperty flags");
1047 }
1048 #endif
1049
1050 //------------------------------format-----------------------------------------
1051 // Print as assembly
1052 void Node::format( PhaseRegAlloc *, outputStream *st ) const {}
1053 //------------------------------emit-------------------------------------------
1054 // Emit bytes starting at parameter 'ptr'.
1055 void Node::emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const {}
1056 //------------------------------size-------------------------------------------
1057 // Size of instruction in bytes
1058 uint Node::size(PhaseRegAlloc *ra_) const { return 0; }
1059
1060 //------------------------------CFG Construction-------------------------------
1061 // Nodes that end basic blocks, e.g. IfTrue/IfFalse, JumpProjNode, Root,
1062 // Goto and Return.
1063 const Node *Node::is_block_proj() const { return 0; }
1064
1065 // Minimum guaranteed type
1066 const Type *Node::bottom_type() const { return Type::BOTTOM; }
1067
1068
1069 //------------------------------raise_bottom_type------------------------------
1070 // Get the worst-case Type output for this Node.
1071 void Node::raise_bottom_type(const Type* new_type) {
1072 if (is_Type()) {
1073 TypeNode *n = this->as_Type();
1074 if (VerifyAliases) {
1075 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1076 }
1077 n->set_type(new_type);
1078 } else if (is_Load()) {
1079 LoadNode *n = this->as_Load();
1080 if (VerifyAliases) {
1081 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type");
1082 }
1083 n->set_type(new_type);
1084 }
1085 }
1086
1087 //------------------------------Identity---------------------------------------
1088 // Return a node that the given node is equivalent to.
1089 Node* Node::Identity(PhaseGVN* phase) {
1090 return this; // Default to no identities
1091 }
1092
1093 //------------------------------Value------------------------------------------
1094 // Compute a new Type for a node using the Type of the inputs.
1095 const Type* Node::Value(PhaseGVN* phase) const {
1096 return bottom_type(); // Default to worst-case Type
1097 }
1098
1099 //------------------------------Ideal------------------------------------------
1100 //
1101 // 'Idealize' the graph rooted at this Node.
1102 //
1103 // In order to be efficient and flexible there are some subtle invariants
1104 // these Ideal calls need to hold. Running with '+VerifyIterativeGVN' checks
1105 // these invariants, although its too slow to have on by default. If you are
1106 // hacking an Ideal call, be sure to test with +VerifyIterativeGVN!
1107 //
1108 // The Ideal call almost arbitrarily reshape the graph rooted at the 'this'
1109 // pointer. If ANY change is made, it must return the root of the reshaped
1110 // graph - even if the root is the same Node. Example: swapping the inputs
1111 // to an AddINode gives the same answer and same root, but you still have to
1112 // return the 'this' pointer instead of NULL.
1113 //
1114 // You cannot return an OLD Node, except for the 'this' pointer. Use the
1115 // Identity call to return an old Node; basically if Identity can find
1116 // another Node have the Ideal call make no change and return NULL.
1117 // Example: AddINode::Ideal must check for add of zero; in this case it
1118 // returns NULL instead of doing any graph reshaping.
1119 //
1120 // You cannot modify any old Nodes except for the 'this' pointer. Due to
1121 // sharing there may be other users of the old Nodes relying on their current
1122 // semantics. Modifying them will break the other users.
1123 // Example: when reshape "(X+3)+4" into "X+7" you must leave the Node for
1124 // "X+3" unchanged in case it is shared.
1125 //
1126 // If you modify the 'this' pointer's inputs, you should use
1127 // 'set_req'. If you are making a new Node (either as the new root or
1128 // some new internal piece) you may use 'init_req' to set the initial
1129 // value. You can make a new Node with either 'new' or 'clone'. In
1130 // either case, def-use info is correctly maintained.
1131 //
1132 // Example: reshape "(X+3)+4" into "X+7":
1133 // set_req(1, in(1)->in(1));
1134 // set_req(2, phase->intcon(7));
1135 // return this;
1136 // Example: reshape "X*4" into "X<<2"
1137 // return new LShiftINode(in(1), phase->intcon(2));
1138 //
1139 // You must call 'phase->transform(X)' on any new Nodes X you make, except
1140 // for the returned root node. Example: reshape "X*31" with "(X<<5)-X".
1141 // Node *shift=phase->transform(new LShiftINode(in(1),phase->intcon(5)));
1142 // return new AddINode(shift, in(1));
1143 //
1144 // When making a Node for a constant use 'phase->makecon' or 'phase->intcon'.
1145 // These forms are faster than 'phase->transform(new ConNode())' and Do
1146 // The Right Thing with def-use info.
1147 //
1148 // You cannot bury the 'this' Node inside of a graph reshape. If the reshaped
1149 // graph uses the 'this' Node it must be the root. If you want a Node with
1150 // the same Opcode as the 'this' pointer use 'clone'.
1151 //
1152 Node *Node::Ideal(PhaseGVN *phase, bool can_reshape) {
1153 return NULL; // Default to being Ideal already
1154 }
1155
1156 // Some nodes have specific Ideal subgraph transformations only if they are
1157 // unique users of specific nodes. Such nodes should be put on IGVN worklist
1158 // for the transformations to happen.
1159 bool Node::has_special_unique_user() const {
1160 assert(outcnt() == 1, "match only for unique out");
1161 Node* n = unique_out();
1162 int op = Opcode();
1163 if (this->is_Store()) {
1164 // Condition for back-to-back stores folding.
1165 return n->Opcode() == op && n->in(MemNode::Memory) == this;
1166 } else if (this->is_Load()) {
1167 // Condition for removing an unused LoadNode from the MemBarAcquire precedence input
1168 return n->Opcode() == Op_MemBarAcquire;
1169 } else if (op == Op_AddL) {
1170 // Condition for convL2I(addL(x,y)) ==> addI(convL2I(x),convL2I(y))
1171 return n->Opcode() == Op_ConvL2I && n->in(1) == this;
1172 } else if (op == Op_SubI || op == Op_SubL) {
1173 // Condition for subI(x,subI(y,z)) ==> subI(addI(x,z),y)
1174 return n->Opcode() == op && n->in(2) == this;
1175 } else if (is_If() && (n->is_IfFalse() || n->is_IfTrue())) {
1176 // See IfProjNode::Identity()
1177 return true;
1178 }
1179 return false;
1180 };
1181
1182 //--------------------------find_exact_control---------------------------------
1183 // Skip Proj and CatchProj nodes chains. Check for Null and Top.
1184 Node* Node::find_exact_control(Node* ctrl) {
1185 if (ctrl == NULL && this->is_Region())
1186 ctrl = this->as_Region()->is_copy();
1187
1188 if (ctrl != NULL && ctrl->is_CatchProj()) {
1189 if (ctrl->as_CatchProj()->_con == CatchProjNode::fall_through_index)
1190 ctrl = ctrl->in(0);
1191 if (ctrl != NULL && !ctrl->is_top())
1192 ctrl = ctrl->in(0);
1193 }
1194
1195 if (ctrl != NULL && ctrl->is_Proj())
1196 ctrl = ctrl->in(0);
1197
1198 return ctrl;
1199 }
1200
1201 //--------------------------dominates------------------------------------------
1202 // Helper function for MemNode::all_controls_dominate().
1203 // Check if 'this' control node dominates or equal to 'sub' control node.
1204 // We already know that if any path back to Root or Start reaches 'this',
1205 // then all paths so, so this is a simple search for one example,
1206 // not an exhaustive search for a counterexample.
1207 bool Node::dominates(Node* sub, Node_List &nlist) {
1208 assert(this->is_CFG(), "expecting control");
1209 assert(sub != NULL && sub->is_CFG(), "expecting control");
1210
1211 // detect dead cycle without regions
1212 int iterations_without_region_limit = DominatorSearchLimit;
1213
1214 Node* orig_sub = sub;
1215 Node* dom = this;
1216 bool met_dom = false;
1217 nlist.clear();
1218
1219 // Walk 'sub' backward up the chain to 'dom', watching for regions.
1220 // After seeing 'dom', continue up to Root or Start.
1221 // If we hit a region (backward split point), it may be a loop head.
1222 // Keep going through one of the region's inputs. If we reach the
1223 // same region again, go through a different input. Eventually we
1224 // will either exit through the loop head, or give up.
1225 // (If we get confused, break out and return a conservative 'false'.)
1226 while (sub != NULL) {
1227 if (sub->is_top()) break; // Conservative answer for dead code.
1228 if (sub == dom) {
1229 if (nlist.size() == 0) {
1230 // No Region nodes except loops were visited before and the EntryControl
1231 // path was taken for loops: it did not walk in a cycle.
1232 return true;
1233 } else if (met_dom) {
1234 break; // already met before: walk in a cycle
1235 } else {
1236 // Region nodes were visited. Continue walk up to Start or Root
1237 // to make sure that it did not walk in a cycle.
1238 met_dom = true; // first time meet
1239 iterations_without_region_limit = DominatorSearchLimit; // Reset
1240 }
1241 }
1242 if (sub->is_Start() || sub->is_Root()) {
1243 // Success if we met 'dom' along a path to Start or Root.
1244 // We assume there are no alternative paths that avoid 'dom'.
1245 // (This assumption is up to the caller to ensure!)
1246 return met_dom;
1247 }
1248 Node* up = sub->in(0);
1249 // Normalize simple pass-through regions and projections:
1250 up = sub->find_exact_control(up);
1251 // If sub == up, we found a self-loop. Try to push past it.
1252 if (sub == up && sub->is_Loop()) {
1253 // Take loop entry path on the way up to 'dom'.
1254 up = sub->in(1); // in(LoopNode::EntryControl);
1255 } else if (sub == up && sub->is_Region() && sub->req() != 3) {
1256 // Always take in(1) path on the way up to 'dom' for clone regions
1257 // (with only one input) or regions which merge > 2 paths
1258 // (usually used to merge fast/slow paths).
1259 up = sub->in(1);
1260 } else if (sub == up && sub->is_Region()) {
1261 // Try both paths for Regions with 2 input paths (it may be a loop head).
1262 // It could give conservative 'false' answer without information
1263 // which region's input is the entry path.
1264 iterations_without_region_limit = DominatorSearchLimit; // Reset
1265
1266 bool region_was_visited_before = false;
1267 // Was this Region node visited before?
1268 // If so, we have reached it because we accidentally took a
1269 // loop-back edge from 'sub' back into the body of the loop,
1270 // and worked our way up again to the loop header 'sub'.
1271 // So, take the first unexplored path on the way up to 'dom'.
1272 for (int j = nlist.size() - 1; j >= 0; j--) {
1273 intptr_t ni = (intptr_t)nlist.at(j);
1274 Node* visited = (Node*)(ni & ~1);
1275 bool visited_twice_already = ((ni & 1) != 0);
1276 if (visited == sub) {
1277 if (visited_twice_already) {
1278 // Visited 2 paths, but still stuck in loop body. Give up.
1279 return false;
1280 }
1281 // The Region node was visited before only once.
1282 // (We will repush with the low bit set, below.)
1283 nlist.remove(j);
1284 // We will find a new edge and re-insert.
1285 region_was_visited_before = true;
1286 break;
1287 }
1288 }
1289
1290 // Find an incoming edge which has not been seen yet; walk through it.
1291 assert(up == sub, "");
1292 uint skip = region_was_visited_before ? 1 : 0;
1293 for (uint i = 1; i < sub->req(); i++) {
1294 Node* in = sub->in(i);
1295 if (in != NULL && !in->is_top() && in != sub) {
1296 if (skip == 0) {
1297 up = in;
1298 break;
1299 }
1300 --skip; // skip this nontrivial input
1301 }
1302 }
1303
1304 // Set 0 bit to indicate that both paths were taken.
1305 nlist.push((Node*)((intptr_t)sub + (region_was_visited_before ? 1 : 0)));
1306 }
1307
1308 if (up == sub) {
1309 break; // some kind of tight cycle
1310 }
1311 if (up == orig_sub && met_dom) {
1312 // returned back after visiting 'dom'
1313 break; // some kind of cycle
1314 }
1315 if (--iterations_without_region_limit < 0) {
1316 break; // dead cycle
1317 }
1318 sub = up;
1319 }
1320
1321 // Did not meet Root or Start node in pred. chain.
1322 // Conservative answer for dead code.
1323 return false;
1324 }
1325
1326 //------------------------------remove_dead_region-----------------------------
1327 // This control node is dead. Follow the subgraph below it making everything
1328 // using it dead as well. This will happen normally via the usual IterGVN
1329 // worklist but this call is more efficient. Do not update use-def info
1330 // inside the dead region, just at the borders.
1331 static void kill_dead_code( Node *dead, PhaseIterGVN *igvn ) {
1332 // Con's are a popular node to re-hit in the hash table again.
1333 if( dead->is_Con() ) return;
1334
1335 // Can't put ResourceMark here since igvn->_worklist uses the same arena
1336 // for verify pass with +VerifyOpto and we add/remove elements in it here.
1337 Node_List nstack(Thread::current()->resource_area());
1338
1339 Node *top = igvn->C->top();
1340 nstack.push(dead);
1341 bool has_irreducible_loop = igvn->C->has_irreducible_loop();
1342
1343 while (nstack.size() > 0) {
1344 dead = nstack.pop();
1345 if (dead->outcnt() > 0) {
1346 // Keep dead node on stack until all uses are processed.
1347 nstack.push(dead);
1348 // For all Users of the Dead... ;-)
1349 for (DUIterator_Last kmin, k = dead->last_outs(kmin); k >= kmin; ) {
1350 Node* use = dead->last_out(k);
1351 igvn->hash_delete(use); // Yank from hash table prior to mod
1352 if (use->in(0) == dead) { // Found another dead node
1353 assert (!use->is_Con(), "Control for Con node should be Root node.");
1354 use->set_req(0, top); // Cut dead edge to prevent processing
1355 nstack.push(use); // the dead node again.
1356 } else if (!has_irreducible_loop && // Backedge could be alive in irreducible loop
1357 use->is_Loop() && !use->is_Root() && // Don't kill Root (RootNode extends LoopNode)
1358 use->in(LoopNode::EntryControl) == dead) { // Dead loop if its entry is dead
1359 use->set_req(LoopNode::EntryControl, top); // Cut dead edge to prevent processing
1360 use->set_req(0, top); // Cut self edge
1361 nstack.push(use);
1362 } else { // Else found a not-dead user
1363 // Dead if all inputs are top or null
1364 bool dead_use = !use->is_Root(); // Keep empty graph alive
1365 for (uint j = 1; j < use->req(); j++) {
1366 Node* in = use->in(j);
1367 if (in == dead) { // Turn all dead inputs into TOP
1368 use->set_req(j, top);
1369 } else if (in != NULL && !in->is_top()) {
1370 dead_use = false;
1371 }
1372 }
1373 if (dead_use) {
1374 if (use->is_Region()) {
1375 use->set_req(0, top); // Cut self edge
1376 }
1377 nstack.push(use);
1378 } else {
1379 igvn->_worklist.push(use);
1380 }
1381 }
1382 // Refresh the iterator, since any number of kills might have happened.
1383 k = dead->last_outs(kmin);
1384 }
1385 } else { // (dead->outcnt() == 0)
1386 // Done with outputs.
1387 igvn->hash_delete(dead);
1388 igvn->_worklist.remove(dead);
1389 igvn->C->remove_modified_node(dead);
1390 igvn->set_type(dead, Type::TOP);
1391 if (dead->is_macro()) {
1392 igvn->C->remove_macro_node(dead);
1393 }
1394 if (dead->is_expensive()) {
1395 igvn->C->remove_expensive_node(dead);
1396 }
1397 #ifdef _LP64
1398 CastIINode* cast = dead->isa_CastII();
1399 if (cast != NULL && cast->has_range_check()) {
1400 igvn->C->remove_range_check_cast(cast);
1401 }
1402 #endif
1403 igvn->C->record_dead_node(dead->_idx);
1404 // Kill all inputs to the dead guy
1405 for (uint i=0; i < dead->req(); i++) {
1406 Node *n = dead->in(i); // Get input to dead guy
1407 if (n != NULL && !n->is_top()) { // Input is valid?
1408 dead->set_req(i, top); // Smash input away
1409 if (n->outcnt() == 0) { // Input also goes dead?
1410 if (!n->is_Con())
1411 nstack.push(n); // Clear it out as well
1412 } else if (n->outcnt() == 1 &&
1413 n->has_special_unique_user()) {
1414 igvn->add_users_to_worklist( n );
1415 } else if (n->outcnt() <= 2 && n->is_Store()) {
1416 // Push store's uses on worklist to enable folding optimization for
1417 // store/store and store/load to the same address.
1418 // The restriction (outcnt() <= 2) is the same as in set_req_X()
1419 // and remove_globally_dead_node().
1420 igvn->add_users_to_worklist( n );
1421 }
1422 }
1423 }
1424 } // (dead->outcnt() == 0)
1425 } // while (nstack.size() > 0) for outputs
1426 return;
1427 }
1428
1429 //------------------------------remove_dead_region-----------------------------
1430 bool Node::remove_dead_region(PhaseGVN *phase, bool can_reshape) {
1431 Node *n = in(0);
1432 if( !n ) return false;
1433 // Lost control into this guy? I.e., it became unreachable?
1434 // Aggressively kill all unreachable code.
1435 if (can_reshape && n->is_top()) {
1436 kill_dead_code(this, phase->is_IterGVN());
1437 return false; // Node is dead.
1438 }
1439
1440 if( n->is_Region() && n->as_Region()->is_copy() ) {
1441 Node *m = n->nonnull_req();
1442 set_req(0, m);
1443 return true;
1444 }
1445 return false;
1446 }
1447
1448 //------------------------------hash-------------------------------------------
1449 // Hash function over Nodes.
1450 uint Node::hash() const {
1451 uint sum = 0;
1452 for( uint i=0; i<_cnt; i++ ) // Add in all inputs
1453 sum = (sum<<1)-(uintptr_t)in(i); // Ignore embedded NULLs
1454 return (sum>>2) + _cnt + Opcode();
1455 }
1456
1457 //------------------------------cmp--------------------------------------------
1458 // Compare special parts of simple Nodes
1459 uint Node::cmp( const Node &n ) const {
1460 return 1; // Must be same
1461 }
1462
1463 //------------------------------rematerialize-----------------------------------
1464 // Should we clone rather than spill this instruction?
1465 bool Node::rematerialize() const {
1466 if ( is_Mach() )
1467 return this->as_Mach()->rematerialize();
1468 else
1469 return (_flags & Flag_rematerialize) != 0;
1470 }
1471
1472 //------------------------------needs_anti_dependence_check---------------------
1473 // Nodes which use memory without consuming it, hence need antidependences.
1474 bool Node::needs_anti_dependence_check() const {
1475 if( req() < 2 || (_flags & Flag_needs_anti_dependence_check) == 0 )
1476 return false;
1477 else
1478 return in(1)->bottom_type()->has_memory();
1479 }
1480
1481
1482 // Get an integer constant from a ConNode (or CastIINode).
1483 // Return a default value if there is no apparent constant here.
1484 const TypeInt* Node::find_int_type() const {
1485 if (this->is_Type()) {
1486 return this->as_Type()->type()->isa_int();
1487 } else if (this->is_Con()) {
1488 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1489 return this->bottom_type()->isa_int();
1490 }
1491 return NULL;
1492 }
1493
1494 // Get a pointer constant from a ConstNode.
1495 // Returns the constant if it is a pointer ConstNode
1496 intptr_t Node::get_ptr() const {
1497 assert( Opcode() == Op_ConP, "" );
1498 return ((ConPNode*)this)->type()->is_ptr()->get_con();
1499 }
1500
1501 // Get a narrow oop constant from a ConNNode.
1502 intptr_t Node::get_narrowcon() const {
1503 assert( Opcode() == Op_ConN, "" );
1504 return ((ConNNode*)this)->type()->is_narrowoop()->get_con();
1505 }
1506
1507 // Get a long constant from a ConNode.
1508 // Return a default value if there is no apparent constant here.
1509 const TypeLong* Node::find_long_type() const {
1510 if (this->is_Type()) {
1511 return this->as_Type()->type()->isa_long();
1512 } else if (this->is_Con()) {
1513 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode");
1514 return this->bottom_type()->isa_long();
1515 }
1516 return NULL;
1517 }
1518
1519
1520 /**
1521 * Return a ptr type for nodes which should have it.
1522 */
1523 const TypePtr* Node::get_ptr_type() const {
1524 const TypePtr* tp = this->bottom_type()->make_ptr();
1525 #ifdef ASSERT
1526 if (tp == NULL) {
1527 this->dump(1);
1528 assert((tp != NULL), "unexpected node type");
1529 }
1530 #endif
1531 return tp;
1532 }
1533
1534 // Get a double constant from a ConstNode.
1535 // Returns the constant if it is a double ConstNode
1536 jdouble Node::getd() const {
1537 assert( Opcode() == Op_ConD, "" );
1538 return ((ConDNode*)this)->type()->is_double_constant()->getd();
1539 }
1540
1541 // Get a float constant from a ConstNode.
1542 // Returns the constant if it is a float ConstNode
1543 jfloat Node::getf() const {
1544 assert( Opcode() == Op_ConF, "" );
1545 return ((ConFNode*)this)->type()->is_float_constant()->getf();
1546 }
1547
1548 #ifndef PRODUCT
1549
1550 //------------------------------find------------------------------------------
1551 // Find a neighbor of this Node with the given _idx
1552 // If idx is negative, find its absolute value, following both _in and _out.
1553 static void find_recur(Compile* C, Node* &result, Node *n, int idx, bool only_ctrl,
1554 VectorSet* old_space, VectorSet* new_space ) {
1555 int node_idx = (idx >= 0) ? idx : -idx;
1556 if (NotANode(n)) return; // Gracefully handle NULL, -1, 0xabababab, etc.
1557 // Contained in new_space or old_space? Check old_arena first since it's mostly empty.
1558 VectorSet *v = C->old_arena()->contains(n) ? old_space : new_space;
1559 if( v->test(n->_idx) ) return;
1560 if( (int)n->_idx == node_idx
1561 debug_only(|| n->debug_idx() == node_idx) ) {
1562 if (result != NULL)
1563 tty->print("find: " INTPTR_FORMAT " and " INTPTR_FORMAT " both have idx==%d\n",
1564 (uintptr_t)result, (uintptr_t)n, node_idx);
1565 result = n;
1566 }
1567 v->set(n->_idx);
1568 for( uint i=0; i<n->len(); i++ ) {
1569 if( only_ctrl && !(n->is_Region()) && (n->Opcode() != Op_Root) && (i != TypeFunc::Control) ) continue;
1570 find_recur(C, result, n->in(i), idx, only_ctrl, old_space, new_space );
1571 }
1572 // Search along forward edges also:
1573 if (idx < 0 && !only_ctrl) {
1574 for( uint j=0; j<n->outcnt(); j++ ) {
1575 find_recur(C, result, n->raw_out(j), idx, only_ctrl, old_space, new_space );
1576 }
1577 }
1578 #ifdef ASSERT
1579 // Search along debug_orig edges last, checking for cycles
1580 Node* orig = n->debug_orig();
1581 if (orig != NULL) {
1582 do {
1583 if (NotANode(orig)) break;
1584 find_recur(C, result, orig, idx, only_ctrl, old_space, new_space );
1585 orig = orig->debug_orig();
1586 } while (orig != NULL && orig != n->debug_orig());
1587 }
1588 #endif //ASSERT
1589 }
1590
1591 // call this from debugger:
1592 Node* find_node(Node* n, int idx) {
1593 return n->find(idx);
1594 }
1595
1596 //------------------------------find-------------------------------------------
1597 Node* Node::find(int idx) const {
1598 ResourceArea *area = Thread::current()->resource_area();
1599 VectorSet old_space(area), new_space(area);
1600 Node* result = NULL;
1601 find_recur(Compile::current(), result, (Node*) this, idx, false, &old_space, &new_space );
1602 return result;
1603 }
1604
1605 //------------------------------find_ctrl--------------------------------------
1606 // Find an ancestor to this node in the control history with given _idx
1607 Node* Node::find_ctrl(int idx) const {
1608 ResourceArea *area = Thread::current()->resource_area();
1609 VectorSet old_space(area), new_space(area);
1610 Node* result = NULL;
1611 find_recur(Compile::current(), result, (Node*) this, idx, true, &old_space, &new_space );
1612 return result;
1613 }
1614 #endif
1615
1616
1617
1618 #ifndef PRODUCT
1619
1620 // -----------------------------Name-------------------------------------------
1621 extern const char *NodeClassNames[];
1622 const char *Node::Name() const { return NodeClassNames[Opcode()]; }
1623
1624 static bool is_disconnected(const Node* n) {
1625 for (uint i = 0; i < n->req(); i++) {
1626 if (n->in(i) != NULL) return false;
1627 }
1628 return true;
1629 }
1630
1631 #ifdef ASSERT
1632 static void dump_orig(Node* orig, outputStream *st) {
1633 Compile* C = Compile::current();
1634 if (NotANode(orig)) orig = NULL;
1635 if (orig != NULL && !C->node_arena()->contains(orig)) orig = NULL;
1636 if (orig == NULL) return;
1637 st->print(" !orig=");
1638 Node* fast = orig->debug_orig(); // tortoise & hare algorithm to detect loops
1639 if (NotANode(fast)) fast = NULL;
1640 while (orig != NULL) {
1641 bool discon = is_disconnected(orig); // if discon, print [123] else 123
1642 if (discon) st->print("[");
1643 if (!Compile::current()->node_arena()->contains(orig))
1644 st->print("o");
1645 st->print("%d", orig->_idx);
1646 if (discon) st->print("]");
1647 orig = orig->debug_orig();
1648 if (NotANode(orig)) orig = NULL;
1649 if (orig != NULL && !C->node_arena()->contains(orig)) orig = NULL;
1650 if (orig != NULL) st->print(",");
1651 if (fast != NULL) {
1652 // Step fast twice for each single step of orig:
1653 fast = fast->debug_orig();
1654 if (NotANode(fast)) fast = NULL;
1655 if (fast != NULL && fast != orig) {
1656 fast = fast->debug_orig();
1657 if (NotANode(fast)) fast = NULL;
1658 }
1659 if (fast == orig) {
1660 st->print("...");
1661 break;
1662 }
1663 }
1664 }
1665 }
1666
1667 void Node::set_debug_orig(Node* orig) {
1668 _debug_orig = orig;
1669 if (BreakAtNode == 0) return;
1670 if (NotANode(orig)) orig = NULL;
1671 int trip = 10;
1672 while (orig != NULL) {
1673 if (orig->debug_idx() == BreakAtNode || (int)orig->_idx == BreakAtNode) {
1674 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=%d orig._idx=%d orig._debug_idx=%d",
1675 this->_idx, this->debug_idx(), orig->_idx, orig->debug_idx());
1676 BREAKPOINT;
1677 }
1678 orig = orig->debug_orig();
1679 if (NotANode(orig)) orig = NULL;
1680 if (trip-- <= 0) break;
1681 }
1682 }
1683 #endif //ASSERT
1684
1685 //------------------------------dump------------------------------------------
1686 // Dump a Node
1687 void Node::dump(const char* suffix, bool mark, outputStream *st) const {
1688 Compile* C = Compile::current();
1689 bool is_new = C->node_arena()->contains(this);
1690 C->_in_dump_cnt++;
1691 st->print("%c%d%s\t%s\t=== ", is_new ? ' ' : 'o', _idx, mark ? " >" : "", Name());
1692
1693 // Dump the required and precedence inputs
1694 dump_req(st);
1695 dump_prec(st);
1696 // Dump the outputs
1697 dump_out(st);
1698
1699 if (is_disconnected(this)) {
1700 #ifdef ASSERT
1701 st->print(" [%d]",debug_idx());
1702 dump_orig(debug_orig(), st);
1703 #endif
1704 st->cr();
1705 C->_in_dump_cnt--;
1706 return; // don't process dead nodes
1707 }
1708
1709 if (C->clone_map().value(_idx) != 0) {
1710 C->clone_map().dump(_idx);
1711 }
1712 // Dump node-specific info
1713 dump_spec(st);
1714 #ifdef ASSERT
1715 // Dump the non-reset _debug_idx
1716 if (Verbose && WizardMode) {
1717 st->print(" [%d]",debug_idx());
1718 }
1719 #endif
1720
1721 const Type *t = bottom_type();
1722
1723 if (t != NULL && (t->isa_instptr() || t->isa_klassptr())) {
1724 const TypeInstPtr *toop = t->isa_instptr();
1725 const TypeKlassPtr *tkls = t->isa_klassptr();
1726 ciKlass* klass = toop ? toop->klass() : (tkls ? tkls->klass() : NULL );
1727 if (klass && klass->is_loaded() && klass->is_interface()) {
1728 st->print(" Interface:");
1729 } else if (toop) {
1730 st->print(" Oop:");
1731 } else if (tkls) {
1732 st->print(" Klass:");
1733 }
1734 t->dump_on(st);
1735 } else if (t == Type::MEMORY) {
1736 st->print(" Memory:");
1737 MemNode::dump_adr_type(this, adr_type(), st);
1738 } else if (Verbose || WizardMode) {
1739 st->print(" Type:");
1740 if (t) {
1741 t->dump_on(st);
1742 } else {
1743 st->print("no type");
1744 }
1745 } else if (t->isa_vect() && this->is_MachSpillCopy()) {
1746 // Dump MachSpillcopy vector type.
1747 t->dump_on(st);
1748 }
1749 if (is_new) {
1750 debug_only(dump_orig(debug_orig(), st));
1751 Node_Notes* nn = C->node_notes_at(_idx);
1752 if (nn != NULL && !nn->is_clear()) {
1753 if (nn->jvms() != NULL) {
1754 st->print(" !jvms:");
1755 nn->jvms()->dump_spec(st);
1756 }
1757 }
1758 }
1759 if (suffix) st->print("%s", suffix);
1760 C->_in_dump_cnt--;
1761 }
1762
1763 //------------------------------dump_req--------------------------------------
1764 void Node::dump_req(outputStream *st) const {
1765 // Dump the required input edges
1766 for (uint i = 0; i < req(); i++) { // For all required inputs
1767 Node* d = in(i);
1768 if (d == NULL) {
1769 st->print("_ ");
1770 } else if (NotANode(d)) {
1771 st->print("NotANode "); // uninitialized, sentinel, garbage, etc.
1772 } else {
1773 st->print("%c%d ", Compile::current()->node_arena()->contains(d) ? ' ' : 'o', d->_idx);
1774 }
1775 }
1776 }
1777
1778
1779 //------------------------------dump_prec-------------------------------------
1780 void Node::dump_prec(outputStream *st) const {
1781 // Dump the precedence edges
1782 int any_prec = 0;
1783 for (uint i = req(); i < len(); i++) { // For all precedence inputs
1784 Node* p = in(i);
1785 if (p != NULL) {
1786 if (!any_prec++) st->print(" |");
1787 if (NotANode(p)) { st->print("NotANode "); continue; }
1788 st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx);
1789 }
1790 }
1791 }
1792
1793 //------------------------------dump_out--------------------------------------
1794 void Node::dump_out(outputStream *st) const {
1795 // Delimit the output edges
1796 st->print(" [[");
1797 // Dump the output edges
1798 for (uint i = 0; i < _outcnt; i++) { // For all outputs
1799 Node* u = _out[i];
1800 if (u == NULL) {
1801 st->print("_ ");
1802 } else if (NotANode(u)) {
1803 st->print("NotANode ");
1804 } else {
1805 st->print("%c%d ", Compile::current()->node_arena()->contains(u) ? ' ' : 'o', u->_idx);
1806 }
1807 }
1808 st->print("]] ");
1809 }
1810
1811 //----------------------------collect_nodes_i----------------------------------
1812 // Collects nodes from an Ideal graph, starting from a given start node and
1813 // moving in a given direction until a certain depth (distance from the start
1814 // node) is reached. Duplicates are ignored.
1815 // Arguments:
1816 // nstack: the nodes are collected into this array.
1817 // start: the node at which to start collecting.
1818 // direction: if this is a positive number, collect input nodes; if it is
1819 // a negative number, collect output nodes.
1820 // depth: collect nodes up to this distance from the start node.
1821 // include_start: whether to include the start node in the result collection.
1822 // only_ctrl: whether to regard control edges only during traversal.
1823 // only_data: whether to regard data edges only during traversal.
1824 static void collect_nodes_i(GrowableArray<Node*> *nstack, const Node* start, int direction, uint depth, bool include_start, bool only_ctrl, bool only_data) {
1825 Node* s = (Node*) start; // remove const
1826 nstack->append(s);
1827 int begin = 0;
1828 int end = 0;
1829 for(uint i = 0; i < depth; i++) {
1830 end = nstack->length();
1831 for(int j = begin; j < end; j++) {
1832 Node* tp = nstack->at(j);
1833 uint limit = direction > 0 ? tp->len() : tp->outcnt();
1834 for(uint k = 0; k < limit; k++) {
1835 Node* n = direction > 0 ? tp->in(k) : tp->raw_out(k);
1836
1837 if (NotANode(n)) continue;
1838 // do not recurse through top or the root (would reach unrelated stuff)
1839 if (n->is_Root() || n->is_top()) continue;
1840 if (only_ctrl && !n->is_CFG()) continue;
1841 if (only_data && n->is_CFG()) continue;
1842
1843 bool on_stack = nstack->contains(n);
1844 if (!on_stack) {
1845 nstack->append(n);
1846 }
1847 }
1848 }
1849 begin = end;
1850 }
1851 if (!include_start) {
1852 nstack->remove(s);
1853 }
1854 }
1855
1856 //------------------------------dump_nodes-------------------------------------
1857 static void dump_nodes(const Node* start, int d, bool only_ctrl) {
1858 if (NotANode(start)) return;
1859
1860 GrowableArray <Node *> nstack(Compile::current()->live_nodes());
1861 collect_nodes_i(&nstack, start, d, (uint) ABS(d), true, only_ctrl, false);
1862
1863 int end = nstack.length();
1864 if (d > 0) {
1865 for(int j = end-1; j >= 0; j--) {
1866 nstack.at(j)->dump();
1867 }
1868 } else {
1869 for(int j = 0; j < end; j++) {
1870 nstack.at(j)->dump();
1871 }
1872 }
1873 }
1874
1875 //------------------------------dump-------------------------------------------
1876 void Node::dump(int d) const {
1877 dump_nodes(this, d, false);
1878 }
1879
1880 //------------------------------dump_ctrl--------------------------------------
1881 // Dump a Node's control history to depth
1882 void Node::dump_ctrl(int d) const {
1883 dump_nodes(this, d, true);
1884 }
1885
1886 //-----------------------------dump_compact------------------------------------
1887 void Node::dump_comp() const {
1888 this->dump_comp("\n");
1889 }
1890
1891 //-----------------------------dump_compact------------------------------------
1892 // Dump a Node in compact representation, i.e., just print its name and index.
1893 // Nodes can specify additional specifics to print in compact representation by
1894 // implementing dump_compact_spec.
1895 void Node::dump_comp(const char* suffix, outputStream *st) const {
1896 Compile* C = Compile::current();
1897 C->_in_dump_cnt++;
1898 st->print("%s(%d)", Name(), _idx);
1899 this->dump_compact_spec(st);
1900 if (suffix) {
1901 st->print("%s", suffix);
1902 }
1903 C->_in_dump_cnt--;
1904 }
1905
1906 //----------------------------dump_related-------------------------------------
1907 // Dump a Node's related nodes - the notion of "related" depends on the Node at
1908 // hand and is determined by the implementation of the virtual method rel.
1909 void Node::dump_related() const {
1910 Compile* C = Compile::current();
1911 GrowableArray <Node *> in_rel(C->unique());
1912 GrowableArray <Node *> out_rel(C->unique());
1913 this->related(&in_rel, &out_rel, false);
1914 for (int i = in_rel.length() - 1; i >= 0; i--) {
1915 in_rel.at(i)->dump();
1916 }
1917 this->dump("\n", true);
1918 for (int i = 0; i < out_rel.length(); i++) {
1919 out_rel.at(i)->dump();
1920 }
1921 }
1922
1923 //----------------------------dump_related-------------------------------------
1924 // Dump a Node's related nodes up to a given depth (distance from the start
1925 // node).
1926 // Arguments:
1927 // d_in: depth for input nodes.
1928 // d_out: depth for output nodes (note: this also is a positive number).
1929 void Node::dump_related(uint d_in, uint d_out) const {
1930 Compile* C = Compile::current();
1931 GrowableArray <Node *> in_rel(C->unique());
1932 GrowableArray <Node *> out_rel(C->unique());
1933
1934 // call collect_nodes_i directly
1935 collect_nodes_i(&in_rel, this, 1, d_in, false, false, false);
1936 collect_nodes_i(&out_rel, this, -1, d_out, false, false, false);
1937
1938 for (int i = in_rel.length() - 1; i >= 0; i--) {
1939 in_rel.at(i)->dump();
1940 }
1941 this->dump("\n", true);
1942 for (int i = 0; i < out_rel.length(); i++) {
1943 out_rel.at(i)->dump();
1944 }
1945 }
1946
1947 //------------------------dump_related_compact---------------------------------
1948 // Dump a Node's related nodes in compact representation. The notion of
1949 // "related" depends on the Node at hand and is determined by the implementation
1950 // of the virtual method rel.
1951 void Node::dump_related_compact() const {
1952 Compile* C = Compile::current();
1953 GrowableArray <Node *> in_rel(C->unique());
1954 GrowableArray <Node *> out_rel(C->unique());
1955 this->related(&in_rel, &out_rel, true);
1956 int n_in = in_rel.length();
1957 int n_out = out_rel.length();
1958
1959 this->dump_comp(n_in == 0 ? "\n" : " ");
1960 for (int i = 0; i < n_in; i++) {
1961 in_rel.at(i)->dump_comp(i == n_in - 1 ? "\n" : " ");
1962 }
1963 for (int i = 0; i < n_out; i++) {
1964 out_rel.at(i)->dump_comp(i == n_out - 1 ? "\n" : " ");
1965 }
1966 }
1967
1968 //------------------------------related----------------------------------------
1969 // Collect a Node's related nodes. The default behaviour just collects the
1970 // inputs and outputs at depth 1, including both control and data flow edges,
1971 // regardless of whether the presentation is compact or not. For data nodes,
1972 // the default is to collect all data inputs (till level 1 if compact), and
1973 // outputs till level 1.
1974 void Node::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
1975 if (this->is_CFG()) {
1976 collect_nodes_i(in_rel, this, 1, 1, false, false, false);
1977 collect_nodes_i(out_rel, this, -1, 1, false, false, false);
1978 } else {
1979 if (compact) {
1980 this->collect_nodes(in_rel, 1, false, true);
1981 } else {
1982 this->collect_nodes_in_all_data(in_rel, false);
1983 }
1984 this->collect_nodes(out_rel, -1, false, false);
1985 }
1986 }
1987
1988 //---------------------------collect_nodes-------------------------------------
1989 // An entry point to the low-level node collection facility, to start from a
1990 // given node in the graph. The start node is by default not included in the
1991 // result.
1992 // Arguments:
1993 // ns: collect the nodes into this data structure.
1994 // d: the depth (distance from start node) to which nodes should be
1995 // collected. A value >0 indicates input nodes, a value <0, output
1996 // nodes.
1997 // ctrl: include only control nodes.
1998 // data: include only data nodes.
1999 void Node::collect_nodes(GrowableArray<Node*> *ns, int d, bool ctrl, bool data) const {
2000 if (ctrl && data) {
2001 // ignore nonsensical combination
2002 return;
2003 }
2004 collect_nodes_i(ns, this, d, (uint) ABS(d), false, ctrl, data);
2005 }
2006
2007 //--------------------------collect_nodes_in-----------------------------------
2008 static void collect_nodes_in(Node* start, GrowableArray<Node*> *ns, bool primary_is_data, bool collect_secondary) {
2009 // The maximum depth is determined using a BFS that visits all primary (data
2010 // or control) inputs and increments the depth at each level.
2011 uint d_in = 0;
2012 GrowableArray<Node*> nodes(Compile::current()->unique());
2013 nodes.push(start);
2014 int nodes_at_current_level = 1;
2015 int n_idx = 0;
2016 while (nodes_at_current_level > 0) {
2017 // Add all primary inputs reachable from the current level to the list, and
2018 // increase the depth if there were any.
2019 int nodes_at_next_level = 0;
2020 bool nodes_added = false;
2021 while (nodes_at_current_level > 0) {
2022 nodes_at_current_level--;
2023 Node* current = nodes.at(n_idx++);
2024 for (uint i = 0; i < current->len(); i++) {
2025 Node* n = current->in(i);
2026 if (NotANode(n)) {
2027 continue;
2028 }
2029 if ((primary_is_data && n->is_CFG()) || (!primary_is_data && !n->is_CFG())) {
2030 continue;
2031 }
2032 if (!nodes.contains(n)) {
2033 nodes.push(n);
2034 nodes_added = true;
2035 nodes_at_next_level++;
2036 }
2037 }
2038 }
2039 if (nodes_added) {
2040 d_in++;
2041 }
2042 nodes_at_current_level = nodes_at_next_level;
2043 }
2044 start->collect_nodes(ns, d_in, !primary_is_data, primary_is_data);
2045 if (collect_secondary) {
2046 // Now, iterate over the secondary nodes in ns and add the respective
2047 // boundary reachable from them.
2048 GrowableArray<Node*> sns(Compile::current()->unique());
2049 for (GrowableArrayIterator<Node*> it = ns->begin(); it != ns->end(); ++it) {
2050 Node* n = *it;
2051 n->collect_nodes(&sns, 1, primary_is_data, !primary_is_data);
2052 for (GrowableArrayIterator<Node*> d = sns.begin(); d != sns.end(); ++d) {
2053 ns->append_if_missing(*d);
2054 }
2055 sns.clear();
2056 }
2057 }
2058 }
2059
2060 //---------------------collect_nodes_in_all_data-------------------------------
2061 // Collect the entire data input graph. Include the control boundary if
2062 // requested.
2063 // Arguments:
2064 // ns: collect the nodes into this data structure.
2065 // ctrl: if true, include the control boundary.
2066 void Node::collect_nodes_in_all_data(GrowableArray<Node*> *ns, bool ctrl) const {
2067 collect_nodes_in((Node*) this, ns, true, ctrl);
2068 }
2069
2070 //--------------------------collect_nodes_in_all_ctrl--------------------------
2071 // Collect the entire control input graph. Include the data boundary if
2072 // requested.
2073 // ns: collect the nodes into this data structure.
2074 // data: if true, include the control boundary.
2075 void Node::collect_nodes_in_all_ctrl(GrowableArray<Node*> *ns, bool data) const {
2076 collect_nodes_in((Node*) this, ns, false, data);
2077 }
2078
2079 //------------------collect_nodes_out_all_ctrl_boundary------------------------
2080 // Collect the entire output graph until hitting control node boundaries, and
2081 // include those.
2082 void Node::collect_nodes_out_all_ctrl_boundary(GrowableArray<Node*> *ns) const {
2083 // Perform a BFS and stop at control nodes.
2084 GrowableArray<Node*> nodes(Compile::current()->unique());
2085 nodes.push((Node*) this);
2086 while (nodes.length() > 0) {
2087 Node* current = nodes.pop();
2088 if (NotANode(current)) {
2089 continue;
2090 }
2091 ns->append_if_missing(current);
2092 if (!current->is_CFG()) {
2093 for (DUIterator i = current->outs(); current->has_out(i); i++) {
2094 nodes.push(current->out(i));
2095 }
2096 }
2097 }
2098 ns->remove((Node*) this);
2099 }
2100
2101 // VERIFICATION CODE
2102 // For each input edge to a node (ie - for each Use-Def edge), verify that
2103 // there is a corresponding Def-Use edge.
2104 //------------------------------verify_edges-----------------------------------
2105 void Node::verify_edges(Unique_Node_List &visited) {
2106 uint i, j, idx;
2107 int cnt;
2108 Node *n;
2109
2110 // Recursive termination test
2111 if (visited.member(this)) return;
2112 visited.push(this);
2113
2114 // Walk over all input edges, checking for correspondence
2115 for( i = 0; i < len(); i++ ) {
2116 n = in(i);
2117 if (n != NULL && !n->is_top()) {
2118 // Count instances of (Node *)this
2119 cnt = 0;
2120 for (idx = 0; idx < n->_outcnt; idx++ ) {
2121 if (n->_out[idx] == (Node *)this) cnt++;
2122 }
2123 assert( cnt > 0,"Failed to find Def-Use edge." );
2124 // Check for duplicate edges
2125 // walk the input array downcounting the input edges to n
2126 for( j = 0; j < len(); j++ ) {
2127 if( in(j) == n ) cnt--;
2128 }
2129 assert( cnt == 0,"Mismatched edge count.");
2130 } else if (n == NULL) {
2131 assert(i >= req() || i == 0 || is_Region() || is_Phi(), "only regions or phis have null data edges");
2132 } else {
2133 assert(n->is_top(), "sanity");
2134 // Nothing to check.
2135 }
2136 }
2137 // Recursive walk over all input edges
2138 for( i = 0; i < len(); i++ ) {
2139 n = in(i);
2140 if( n != NULL )
2141 in(i)->verify_edges(visited);
2142 }
2143 }
2144
2145 //------------------------------verify_recur-----------------------------------
2146 static const Node *unique_top = NULL;
2147
2148 void Node::verify_recur(const Node *n, int verify_depth,
2149 VectorSet &old_space, VectorSet &new_space) {
2150 if ( verify_depth == 0 ) return;
2151 if (verify_depth > 0) --verify_depth;
2152
2153 Compile* C = Compile::current();
2154
2155 // Contained in new_space or old_space?
2156 VectorSet *v = C->node_arena()->contains(n) ? &new_space : &old_space;
2157 // Check for visited in the proper space. Numberings are not unique
2158 // across spaces so we need a separate VectorSet for each space.
2159 if( v->test_set(n->_idx) ) return;
2160
2161 if (n->is_Con() && n->bottom_type() == Type::TOP) {
2162 if (C->cached_top_node() == NULL)
2163 C->set_cached_top_node((Node*)n);
2164 assert(C->cached_top_node() == n, "TOP node must be unique");
2165 }
2166
2167 for( uint i = 0; i < n->len(); i++ ) {
2168 Node *x = n->in(i);
2169 if (!x || x->is_top()) continue;
2170
2171 // Verify my input has a def-use edge to me
2172 if (true /*VerifyDefUse*/) {
2173 // Count use-def edges from n to x
2174 int cnt = 0;
2175 for( uint j = 0; j < n->len(); j++ )
2176 if( n->in(j) == x )
2177 cnt++;
2178 // Count def-use edges from x to n
2179 uint max = x->_outcnt;
2180 for( uint k = 0; k < max; k++ )
2181 if (x->_out[k] == n)
2182 cnt--;
2183 assert( cnt == 0, "mismatched def-use edge counts" );
2184 }
2185
2186 verify_recur(x, verify_depth, old_space, new_space);
2187 }
2188
2189 }
2190
2191 //------------------------------verify-----------------------------------------
2192 // Check Def-Use info for my subgraph
2193 void Node::verify() const {
2194 Compile* C = Compile::current();
2195 Node* old_top = C->cached_top_node();
2196 ResourceMark rm;
2197 ResourceArea *area = Thread::current()->resource_area();
2198 VectorSet old_space(area), new_space(area);
2199 verify_recur(this, -1, old_space, new_space);
2200 C->set_cached_top_node(old_top);
2201 }
2202 #endif
2203
2204
2205 //------------------------------walk-------------------------------------------
2206 // Graph walk, with both pre-order and post-order functions
2207 void Node::walk(NFunc pre, NFunc post, void *env) {
2208 VectorSet visited(Thread::current()->resource_area()); // Setup for local walk
2209 walk_(pre, post, env, visited);
2210 }
2211
2212 void Node::walk_(NFunc pre, NFunc post, void *env, VectorSet &visited) {
2213 if( visited.test_set(_idx) ) return;
2214 pre(*this,env); // Call the pre-order walk function
2215 for( uint i=0; i<_max; i++ )
2216 if( in(i) ) // Input exists and is not walked?
2217 in(i)->walk_(pre,post,env,visited); // Walk it with pre & post functions
2218 post(*this,env); // Call the post-order walk function
2219 }
2220
2221 void Node::nop(Node &, void*) {}
2222
2223 //------------------------------Registers--------------------------------------
2224 // Do we Match on this edge index or not? Generally false for Control
2225 // and true for everything else. Weird for calls & returns.
2226 uint Node::match_edge(uint idx) const {
2227 return idx; // True for other than index 0 (control)
2228 }
2229
2230 static RegMask _not_used_at_all;
2231 // Register classes are defined for specific machines
2232 const RegMask &Node::out_RegMask() const {
2233 ShouldNotCallThis();
2234 return _not_used_at_all;
2235 }
2236
2237 const RegMask &Node::in_RegMask(uint) const {
2238 ShouldNotCallThis();
2239 return _not_used_at_all;
2240 }
2241
2242 //=============================================================================
2243 //-----------------------------------------------------------------------------
2244 void Node_Array::reset( Arena *new_arena ) {
2245 _a->Afree(_nodes,_max*sizeof(Node*));
2246 _max = 0;
2247 _nodes = NULL;
2248 _a = new_arena;
2249 }
2250
2251 //------------------------------clear------------------------------------------
2252 // Clear all entries in _nodes to NULL but keep storage
2253 void Node_Array::clear() {
2254 Copy::zero_to_bytes( _nodes, _max*sizeof(Node*) );
2255 }
2256
2257 //-----------------------------------------------------------------------------
2258 void Node_Array::grow( uint i ) {
2259 if( !_max ) {
2260 _max = 1;
2261 _nodes = (Node**)_a->Amalloc( _max * sizeof(Node*) );
2262 _nodes[0] = NULL;
2263 }
2264 uint old = _max;
2265 while( i >= _max ) _max <<= 1; // Double to fit
2266 _nodes = (Node**)_a->Arealloc( _nodes, old*sizeof(Node*),_max*sizeof(Node*));
2267 Copy::zero_to_bytes( &_nodes[old], (_max-old)*sizeof(Node*) );
2268 }
2269
2270 //-----------------------------------------------------------------------------
2271 void Node_Array::insert( uint i, Node *n ) {
2272 if( _nodes[_max-1] ) grow(_max); // Get more space if full
2273 Copy::conjoint_words_to_higher((HeapWord*)&_nodes[i], (HeapWord*)&_nodes[i+1], ((_max-i-1)*sizeof(Node*)));
2274 _nodes[i] = n;
2275 }
2276
2277 //-----------------------------------------------------------------------------
2278 void Node_Array::remove( uint i ) {
2279 Copy::conjoint_words_to_lower((HeapWord*)&_nodes[i+1], (HeapWord*)&_nodes[i], ((_max-i-1)*sizeof(Node*)));
2280 _nodes[_max-1] = NULL;
2281 }
2282
2283 //-----------------------------------------------------------------------------
2284 void Node_Array::sort( C_sort_func_t func) {
2285 qsort( _nodes, _max, sizeof( Node* ), func );
2286 }
2287
2288 //-----------------------------------------------------------------------------
2289 void Node_Array::dump() const {
2290 #ifndef PRODUCT
2291 for( uint i = 0; i < _max; i++ ) {
2292 Node *nn = _nodes[i];
2293 if( nn != NULL ) {
2294 tty->print("%5d--> ",i); nn->dump();
2295 }
2296 }
2297 #endif
2298 }
2299
2300 //--------------------------is_iteratively_computed------------------------------
2301 // Operation appears to be iteratively computed (such as an induction variable)
2302 // It is possible for this operation to return false for a loop-varying
2303 // value, if it appears (by local graph inspection) to be computed by a simple conditional.
2304 bool Node::is_iteratively_computed() {
2305 if (ideal_reg()) { // does operation have a result register?
2306 for (uint i = 1; i < req(); i++) {
2307 Node* n = in(i);
2308 if (n != NULL && n->is_Phi()) {
2309 for (uint j = 1; j < n->req(); j++) {
2310 if (n->in(j) == this) {
2311 return true;
2312 }
2313 }
2314 }
2315 }
2316 }
2317 return false;
2318 }
2319
2320 //--------------------------find_similar------------------------------
2321 // Return a node with opcode "opc" and same inputs as "this" if one can
2322 // be found; Otherwise return NULL;
2323 Node* Node::find_similar(int opc) {
2324 if (req() >= 2) {
2325 Node* def = in(1);
2326 if (def && def->outcnt() >= 2) {
2327 for (DUIterator_Fast dmax, i = def->fast_outs(dmax); i < dmax; i++) {
2328 Node* use = def->fast_out(i);
2329 if (use->Opcode() == opc &&
2330 use->req() == req()) {
2331 uint j;
2332 for (j = 0; j < use->req(); j++) {
2333 if (use->in(j) != in(j)) {
2334 break;
2335 }
2336 }
2337 if (j == use->req()) {
2338 return use;
2339 }
2340 }
2341 }
2342 }
2343 }
2344 return NULL;
2345 }
2346
2347
2348 //--------------------------unique_ctrl_out------------------------------
2349 // Return the unique control out if only one. Null if none or more than one.
2350 Node* Node::unique_ctrl_out() const {
2351 Node* found = NULL;
2352 for (uint i = 0; i < outcnt(); i++) {
2353 Node* use = raw_out(i);
2354 if (use->is_CFG() && use != this) {
2355 if (found != NULL) return NULL;
2356 found = use;
2357 }
2358 }
2359 return found;
2360 }
2361
2362 void Node::ensure_control_or_add_prec(Node* c) {
2363 if (in(0) == NULL) {
2364 set_req(0, c);
2365 } else if (in(0) != c) {
2366 add_prec(c);
2367 }
2368 }
2369
2370 //=============================================================================
2371 //------------------------------yank-------------------------------------------
2372 // Find and remove
2373 void Node_List::yank( Node *n ) {
2374 uint i;
2375 for( i = 0; i < _cnt; i++ )
2376 if( _nodes[i] == n )
2377 break;
2378
2379 if( i < _cnt )
2380 _nodes[i] = _nodes[--_cnt];
2381 }
2382
2383 //------------------------------dump-------------------------------------------
2384 void Node_List::dump() const {
2385 #ifndef PRODUCT
2386 for( uint i = 0; i < _cnt; i++ )
2387 if( _nodes[i] ) {
2388 tty->print("%5d--> ",i);
2389 _nodes[i]->dump();
2390 }
2391 #endif
2392 }
2393
2394 void Node_List::dump_simple() const {
2395 #ifndef PRODUCT
2396 for( uint i = 0; i < _cnt; i++ )
2397 if( _nodes[i] ) {
2398 tty->print(" %d", _nodes[i]->_idx);
2399 } else {
2400 tty->print(" NULL");
2401 }
2402 #endif
2403 }
2404
2405 //=============================================================================
2406 //------------------------------remove-----------------------------------------
2407 void Unique_Node_List::remove( Node *n ) {
2408 if( _in_worklist[n->_idx] ) {
2409 for( uint i = 0; i < size(); i++ )
2410 if( _nodes[i] == n ) {
2411 map(i,Node_List::pop());
2412 _in_worklist >>= n->_idx;
2413 return;
2414 }
2415 ShouldNotReachHere();
2416 }
2417 }
2418
2419 //-----------------------remove_useless_nodes----------------------------------
2420 // Remove useless nodes from worklist
2421 void Unique_Node_List::remove_useless_nodes(VectorSet &useful) {
2422
2423 for( uint i = 0; i < size(); ++i ) {
2424 Node *n = at(i);
2425 assert( n != NULL, "Did not expect null entries in worklist");
2426 if( ! useful.test(n->_idx) ) {
2427 _in_worklist >>= n->_idx;
2428 map(i,Node_List::pop());
2429 // Node *replacement = Node_List::pop();
2430 // if( i != size() ) { // Check if removing last entry
2431 // _nodes[i] = replacement;
2432 // }
2433 --i; // Visit popped node
2434 // If it was last entry, loop terminates since size() was also reduced
2435 }
2436 }
2437 }
2438
2439 //=============================================================================
2440 void Node_Stack::grow() {
2441 size_t old_top = pointer_delta(_inode_top,_inodes,sizeof(INode)); // save _top
2442 size_t old_max = pointer_delta(_inode_max,_inodes,sizeof(INode));
2443 size_t max = old_max << 1; // max * 2
2444 _inodes = REALLOC_ARENA_ARRAY(_a, INode, _inodes, old_max, max);
2445 _inode_max = _inodes + max;
2446 _inode_top = _inodes + old_top; // restore _top
2447 }
2448
2449 // Node_Stack is used to map nodes.
2450 Node* Node_Stack::find(uint idx) const {
2451 uint sz = size();
2452 for (uint i=0; i < sz; i++) {
2453 if (idx == index_at(i) )
2454 return node_at(i);
2455 }
2456 return NULL;
2457 }
2458
2459 //=============================================================================
2460 uint TypeNode::size_of() const { return sizeof(*this); }
2461 #ifndef PRODUCT
2462 void TypeNode::dump_spec(outputStream *st) const {
2463 if( !Verbose && !WizardMode ) {
2464 // standard dump does this in Verbose and WizardMode
2465 st->print(" #"); _type->dump_on(st);
2466 }
2467 }
2468
2469 void TypeNode::dump_compact_spec(outputStream *st) const {
2470 st->print("#");
2471 _type->dump_on(st);
2472 }
2473 #endif
2474 uint TypeNode::hash() const {
2475 return Node::hash() + _type->hash();
2476 }
2477 uint TypeNode::cmp( const Node &n ) const
2478 { return !Type::cmp( _type, ((TypeNode&)n)._type ); }
2479 const Type *TypeNode::bottom_type() const { return _type; }
2480 const Type* TypeNode::Value(PhaseGVN* phase) const { return _type; }
2481
2482 //------------------------------ideal_reg--------------------------------------
2483 uint TypeNode::ideal_reg() const {
2484 return _type->ideal_reg();
2485 }