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src/share/vm/opto/phaseX.cpp@535618ab1c04
src/share/vm/opto/phaseX.cpp
Wed, 27 Jan 2016 09:02:51 +0100
- author
- thartmann
- date
- Wed, 27 Jan 2016 09:02:51 +0100
- changeset 8285
- 535618ab1c04
- parent 8193
- 70649f10b88c
- child 8504
- a96cf90239c6
- permissions
- -rw-r--r--
6675699: need comprehensive fix for unconstrained ConvI2L with narrowed type
Summary: Emit CastII to make narrow ConvI2L dependent on the corresponding range check.
Reviewed-by: kvn, roland
1 /*
2 * Copyright (c) 1997, 2014, 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 */
25 #include "precompiled.hpp"
26 #include "memory/allocation.inline.hpp"
27 #include "opto/block.hpp"
28 #include "opto/callnode.hpp"
29 #include "opto/cfgnode.hpp"
30 #include "opto/connode.hpp"
31 #include "opto/idealGraphPrinter.hpp"
32 #include "opto/loopnode.hpp"
33 #include "opto/machnode.hpp"
34 #include "opto/opcodes.hpp"
35 #include "opto/phaseX.hpp"
36 #include "opto/regalloc.hpp"
37 #include "opto/rootnode.hpp"
39 //=============================================================================
40 #define NODE_HASH_MINIMUM_SIZE 255
41 //------------------------------NodeHash---------------------------------------
42 NodeHash::NodeHash(uint est_max_size) :
43 _max( round_up(est_max_size < NODE_HASH_MINIMUM_SIZE ? NODE_HASH_MINIMUM_SIZE : est_max_size) ),
44 _a(Thread::current()->resource_area()),
45 _table( NEW_ARENA_ARRAY( _a , Node* , _max ) ), // (Node**)_a->Amalloc(_max * sizeof(Node*)) ),
46 _inserts(0), _insert_limit( insert_limit() ),
47 _look_probes(0), _lookup_hits(0), _lookup_misses(0),
48 _total_insert_probes(0), _total_inserts(0),
49 _insert_probes(0), _grows(0) {
50 // _sentinel must be in the current node space
51 _sentinel = new (Compile::current()) ProjNode(NULL, TypeFunc::Control);
52 memset(_table,0,sizeof(Node*)*_max);
53 }
55 //------------------------------NodeHash---------------------------------------
56 NodeHash::NodeHash(Arena *arena, uint est_max_size) :
57 _max( round_up(est_max_size < NODE_HASH_MINIMUM_SIZE ? NODE_HASH_MINIMUM_SIZE : est_max_size) ),
58 _a(arena),
59 _table( NEW_ARENA_ARRAY( _a , Node* , _max ) ),
60 _inserts(0), _insert_limit( insert_limit() ),
61 _look_probes(0), _lookup_hits(0), _lookup_misses(0),
62 _delete_probes(0), _delete_hits(0), _delete_misses(0),
63 _total_insert_probes(0), _total_inserts(0),
64 _insert_probes(0), _grows(0) {
65 // _sentinel must be in the current node space
66 _sentinel = new (Compile::current()) ProjNode(NULL, TypeFunc::Control);
67 memset(_table,0,sizeof(Node*)*_max);
68 }
70 //------------------------------NodeHash---------------------------------------
71 NodeHash::NodeHash(NodeHash *nh) {
72 debug_only(_table = (Node**)badAddress); // interact correctly w/ operator=
73 // just copy in all the fields
74 *this = *nh;
75 // nh->_sentinel must be in the current node space
76 }
78 void NodeHash::replace_with(NodeHash *nh) {
79 debug_only(_table = (Node**)badAddress); // interact correctly w/ operator=
80 // just copy in all the fields
81 *this = *nh;
82 // nh->_sentinel must be in the current node space
83 }
85 //------------------------------hash_find--------------------------------------
86 // Find in hash table
87 Node *NodeHash::hash_find( const Node *n ) {
88 // ((Node*)n)->set_hash( n->hash() );
89 uint hash = n->hash();
90 if (hash == Node::NO_HASH) {
91 debug_only( _lookup_misses++ );
92 return NULL;
93 }
94 uint key = hash & (_max-1);
95 uint stride = key | 0x01;
96 debug_only( _look_probes++ );
97 Node *k = _table[key]; // Get hashed value
98 if( !k ) { // ?Miss?
99 debug_only( _lookup_misses++ );
100 return NULL; // Miss!
101 }
103 int op = n->Opcode();
104 uint req = n->req();
105 while( 1 ) { // While probing hash table
106 if( k->req() == req && // Same count of inputs
107 k->Opcode() == op ) { // Same Opcode
108 for( uint i=0; i<req; i++ )
109 if( n->in(i)!=k->in(i)) // Different inputs?
110 goto collision; // "goto" is a speed hack...
111 if( n->cmp(*k) ) { // Check for any special bits
112 debug_only( _lookup_hits++ );
113 return k; // Hit!
114 }
115 }
116 collision:
117 debug_only( _look_probes++ );
118 key = (key + stride/*7*/) & (_max-1); // Stride through table with relative prime
119 k = _table[key]; // Get hashed value
120 if( !k ) { // ?Miss?
121 debug_only( _lookup_misses++ );
122 return NULL; // Miss!
123 }
124 }
125 ShouldNotReachHere();
126 return NULL;
127 }
129 //------------------------------hash_find_insert-------------------------------
130 // Find in hash table, insert if not already present
131 // Used to preserve unique entries in hash table
132 Node *NodeHash::hash_find_insert( Node *n ) {
133 // n->set_hash( );
134 uint hash = n->hash();
135 if (hash == Node::NO_HASH) {
136 debug_only( _lookup_misses++ );
137 return NULL;
138 }
139 uint key = hash & (_max-1);
140 uint stride = key | 0x01; // stride must be relatively prime to table siz
141 uint first_sentinel = 0; // replace a sentinel if seen.
142 debug_only( _look_probes++ );
143 Node *k = _table[key]; // Get hashed value
144 if( !k ) { // ?Miss?
145 debug_only( _lookup_misses++ );
146 _table[key] = n; // Insert into table!
147 debug_only(n->enter_hash_lock()); // Lock down the node while in the table.
148 check_grow(); // Grow table if insert hit limit
149 return NULL; // Miss!
150 }
151 else if( k == _sentinel ) {
152 first_sentinel = key; // Can insert here
153 }
155 int op = n->Opcode();
156 uint req = n->req();
157 while( 1 ) { // While probing hash table
158 if( k->req() == req && // Same count of inputs
159 k->Opcode() == op ) { // Same Opcode
160 for( uint i=0; i<req; i++ )
161 if( n->in(i)!=k->in(i)) // Different inputs?
162 goto collision; // "goto" is a speed hack...
163 if( n->cmp(*k) ) { // Check for any special bits
164 debug_only( _lookup_hits++ );
165 return k; // Hit!
166 }
167 }
168 collision:
169 debug_only( _look_probes++ );
170 key = (key + stride) & (_max-1); // Stride through table w/ relative prime
171 k = _table[key]; // Get hashed value
172 if( !k ) { // ?Miss?
173 debug_only( _lookup_misses++ );
174 key = (first_sentinel == 0) ? key : first_sentinel; // ?saw sentinel?
175 _table[key] = n; // Insert into table!
176 debug_only(n->enter_hash_lock()); // Lock down the node while in the table.
177 check_grow(); // Grow table if insert hit limit
178 return NULL; // Miss!
179 }
180 else if( first_sentinel == 0 && k == _sentinel ) {
181 first_sentinel = key; // Can insert here
182 }
184 }
185 ShouldNotReachHere();
186 return NULL;
187 }
189 //------------------------------hash_insert------------------------------------
190 // Insert into hash table
191 void NodeHash::hash_insert( Node *n ) {
192 // // "conflict" comments -- print nodes that conflict
193 // bool conflict = false;
194 // n->set_hash();
195 uint hash = n->hash();
196 if (hash == Node::NO_HASH) {
197 return;
198 }
199 check_grow();
200 uint key = hash & (_max-1);
201 uint stride = key | 0x01;
203 while( 1 ) { // While probing hash table
204 debug_only( _insert_probes++ );
205 Node *k = _table[key]; // Get hashed value
206 if( !k || (k == _sentinel) ) break; // Found a slot
207 assert( k != n, "already inserted" );
208 // if( PrintCompilation && PrintOptoStatistics && Verbose ) { tty->print(" conflict: "); k->dump(); conflict = true; }
209 key = (key + stride) & (_max-1); // Stride through table w/ relative prime
210 }
211 _table[key] = n; // Insert into table!
212 debug_only(n->enter_hash_lock()); // Lock down the node while in the table.
213 // if( conflict ) { n->dump(); }
214 }
216 //------------------------------hash_delete------------------------------------
217 // Replace in hash table with sentinel
218 bool NodeHash::hash_delete( const Node *n ) {
219 Node *k;
220 uint hash = n->hash();
221 if (hash == Node::NO_HASH) {
222 debug_only( _delete_misses++ );
223 return false;
224 }
225 uint key = hash & (_max-1);
226 uint stride = key | 0x01;
227 debug_only( uint counter = 0; );
228 for( ; /* (k != NULL) && (k != _sentinel) */; ) {
229 debug_only( counter++ );
230 debug_only( _delete_probes++ );
231 k = _table[key]; // Get hashed value
232 if( !k ) { // Miss?
233 debug_only( _delete_misses++ );
234 #ifdef ASSERT
235 if( VerifyOpto ) {
236 for( uint i=0; i < _max; i++ )
237 assert( _table[i] != n, "changed edges with rehashing" );
238 }
239 #endif
240 return false; // Miss! Not in chain
241 }
242 else if( n == k ) {
243 debug_only( _delete_hits++ );
244 _table[key] = _sentinel; // Hit! Label as deleted entry
245 debug_only(((Node*)n)->exit_hash_lock()); // Unlock the node upon removal from table.
246 return true;
247 }
248 else {
249 // collision: move through table with prime offset
250 key = (key + stride/*7*/) & (_max-1);
251 assert( counter <= _insert_limit, "Cycle in hash-table");
252 }
253 }
254 ShouldNotReachHere();
255 return false;
256 }
258 //------------------------------round_up---------------------------------------
259 // Round up to nearest power of 2
260 uint NodeHash::round_up( uint x ) {
261 x += (x>>2); // Add 25% slop
262 if( x <16 ) return 16; // Small stuff
263 uint i=16;
264 while( i < x ) i <<= 1; // Double to fit
265 return i; // Return hash table size
266 }
268 //------------------------------grow-------------------------------------------
269 // Grow _table to next power of 2 and insert old entries
270 void NodeHash::grow() {
271 // Record old state
272 uint old_max = _max;
273 Node **old_table = _table;
274 // Construct new table with twice the space
275 _grows++;
276 _total_inserts += _inserts;
277 _total_insert_probes += _insert_probes;
278 _inserts = 0;
279 _insert_probes = 0;
280 _max = _max << 1;
281 _table = NEW_ARENA_ARRAY( _a , Node* , _max ); // (Node**)_a->Amalloc( _max * sizeof(Node*) );
282 memset(_table,0,sizeof(Node*)*_max);
283 _insert_limit = insert_limit();
284 // Insert old entries into the new table
285 for( uint i = 0; i < old_max; i++ ) {
286 Node *m = *old_table++;
287 if( !m || m == _sentinel ) continue;
288 debug_only(m->exit_hash_lock()); // Unlock the node upon removal from old table.
289 hash_insert(m);
290 }
291 }
293 //------------------------------clear------------------------------------------
294 // Clear all entries in _table to NULL but keep storage
295 void NodeHash::clear() {
296 #ifdef ASSERT
297 // Unlock all nodes upon removal from table.
298 for (uint i = 0; i < _max; i++) {
299 Node* n = _table[i];
300 if (!n || n == _sentinel) continue;
301 n->exit_hash_lock();
302 }
303 #endif
305 memset( _table, 0, _max * sizeof(Node*) );
306 }
308 //-----------------------remove_useless_nodes----------------------------------
309 // Remove useless nodes from value table,
310 // implementation does not depend on hash function
311 void NodeHash::remove_useless_nodes(VectorSet &useful) {
313 // Dead nodes in the hash table inherited from GVN should not replace
314 // existing nodes, remove dead nodes.
315 uint max = size();
316 Node *sentinel_node = sentinel();
317 for( uint i = 0; i < max; ++i ) {
318 Node *n = at(i);
319 if(n != NULL && n != sentinel_node && !useful.test(n->_idx)) {
320 debug_only(n->exit_hash_lock()); // Unlock the node when removed
321 _table[i] = sentinel_node; // Replace with placeholder
322 }
323 }
324 }
327 void NodeHash::check_no_speculative_types() {
328 #ifdef ASSERT
329 uint max = size();
330 Node *sentinel_node = sentinel();
331 for (uint i = 0; i < max; ++i) {
332 Node *n = at(i);
333 if(n != NULL && n != sentinel_node && n->is_Type()) {
334 TypeNode* tn = n->as_Type();
335 const Type* t = tn->type();
336 const Type* t_no_spec = t->remove_speculative();
337 assert(t == t_no_spec, "dead node in hash table or missed node during speculative cleanup");
338 }
339 }
340 #endif
341 }
343 #ifndef PRODUCT
344 //------------------------------dump-------------------------------------------
345 // Dump statistics for the hash table
346 void NodeHash::dump() {
347 _total_inserts += _inserts;
348 _total_insert_probes += _insert_probes;
349 if (PrintCompilation && PrintOptoStatistics && Verbose && (_inserts > 0)) {
350 if (WizardMode) {
351 for (uint i=0; i<_max; i++) {
352 if (_table[i])
353 tty->print("%d/%d/%d ",i,_table[i]->hash()&(_max-1),_table[i]->_idx);
354 }
355 }
356 tty->print("\nGVN Hash stats: %d grows to %d max_size\n", _grows, _max);
357 tty->print(" %d/%d (%8.1f%% full)\n", _inserts, _max, (double)_inserts/_max*100.0);
358 tty->print(" %dp/(%dh+%dm) (%8.2f probes/lookup)\n", _look_probes, _lookup_hits, _lookup_misses, (double)_look_probes/(_lookup_hits+_lookup_misses));
359 tty->print(" %dp/%di (%8.2f probes/insert)\n", _total_insert_probes, _total_inserts, (double)_total_insert_probes/_total_inserts);
360 // sentinels increase lookup cost, but not insert cost
361 assert((_lookup_misses+_lookup_hits)*4+100 >= _look_probes, "bad hash function");
362 assert( _inserts+(_inserts>>3) < _max, "table too full" );
363 assert( _inserts*3+100 >= _insert_probes, "bad hash function" );
364 }
365 }
367 Node *NodeHash::find_index(uint idx) { // For debugging
368 // Find an entry by its index value
369 for( uint i = 0; i < _max; i++ ) {
370 Node *m = _table[i];
371 if( !m || m == _sentinel ) continue;
372 if( m->_idx == (uint)idx ) return m;
373 }
374 return NULL;
375 }
376 #endif
378 #ifdef ASSERT
379 NodeHash::~NodeHash() {
380 // Unlock all nodes upon destruction of table.
381 if (_table != (Node**)badAddress) clear();
382 }
384 void NodeHash::operator=(const NodeHash& nh) {
385 // Unlock all nodes upon replacement of table.
386 if (&nh == this) return;
387 if (_table != (Node**)badAddress) clear();
388 memcpy(this, &nh, sizeof(*this));
389 // Do not increment hash_lock counts again.
390 // Instead, be sure we never again use the source table.
391 ((NodeHash*)&nh)->_table = (Node**)badAddress;
392 }
395 #endif
398 //=============================================================================
399 //------------------------------PhaseRemoveUseless-----------------------------
400 // 1) Use a breadthfirst walk to collect useful nodes reachable from root.
401 PhaseRemoveUseless::PhaseRemoveUseless(PhaseGVN *gvn, Unique_Node_List *worklist, PhaseNumber phase_num) : Phase(phase_num),
402 _useful(Thread::current()->resource_area()) {
404 // Implementation requires 'UseLoopSafepoints == true' and an edge from root
405 // to each SafePointNode at a backward branch. Inserted in add_safepoint().
406 if( !UseLoopSafepoints || !OptoRemoveUseless ) return;
408 // Identify nodes that are reachable from below, useful.
409 C->identify_useful_nodes(_useful);
410 // Update dead node list
411 C->update_dead_node_list(_useful);
413 // Remove all useless nodes from PhaseValues' recorded types
414 // Must be done before disconnecting nodes to preserve hash-table-invariant
415 gvn->remove_useless_nodes(_useful.member_set());
417 // Remove all useless nodes from future worklist
418 worklist->remove_useless_nodes(_useful.member_set());
420 // Disconnect 'useless' nodes that are adjacent to useful nodes
421 C->remove_useless_nodes(_useful);
423 // Remove edges from "root" to each SafePoint at a backward branch.
424 // They were inserted during parsing (see add_safepoint()) to make infinite
425 // loops without calls or exceptions visible to root, i.e., useful.
426 Node *root = C->root();
427 if( root != NULL ) {
428 for( uint i = root->req(); i < root->len(); ++i ) {
429 Node *n = root->in(i);
430 if( n != NULL && n->is_SafePoint() ) {
431 root->rm_prec(i);
432 --i;
433 }
434 }
435 }
436 }
438 //=============================================================================
439 //------------------------------PhaseRenumberLive------------------------------
440 // First, remove useless nodes (equivalent to identifying live nodes).
441 // Then, renumber live nodes.
442 //
443 // The set of live nodes is returned by PhaseRemoveUseless in the _useful structure.
444 // If the number of live nodes is 'x' (where 'x' == _useful.size()), then the
445 // PhaseRenumberLive updates the node ID of each node (the _idx field) with a unique
446 // value in the range [0, x).
447 //
448 // At the end of the PhaseRenumberLive phase, the compiler's count of unique nodes is
449 // updated to 'x' and the list of dead nodes is reset (as there are no dead nodes).
450 //
451 // The PhaseRenumberLive phase updates two data structures with the new node IDs.
452 // (1) The worklist is used by the PhaseIterGVN phase to identify nodes that must be
453 // processed. A new worklist (with the updated node IDs) is returned in 'new_worklist'.
454 // (2) Type information (the field PhaseGVN::_types) maps type information to each
455 // node ID. The mapping is updated to use the new node IDs as well. Updated type
456 // information is returned in PhaseGVN::_types.
457 //
458 // The PhaseRenumberLive phase does not preserve the order of elements in the worklist.
459 //
460 // Other data structures used by the compiler are not updated. The hash table for value
461 // numbering (the field PhaseGVN::_table) is not updated because computing the hash
462 // values is not based on node IDs. The field PhaseGVN::_nodes is not updated either
463 // because it is empty wherever PhaseRenumberLive is used.
464 PhaseRenumberLive::PhaseRenumberLive(PhaseGVN* gvn,
465 Unique_Node_List* worklist, Unique_Node_List* new_worklist,
466 PhaseNumber phase_num) :
467 PhaseRemoveUseless(gvn, worklist, Remove_Useless_And_Renumber_Live) {
469 assert(RenumberLiveNodes, "RenumberLiveNodes must be set to true for node renumbering to take place");
470 assert(C->live_nodes() == _useful.size(), "the number of live nodes must match the number of useful nodes");
471 assert(gvn->nodes_size() == 0, "GVN must not contain any nodes at this point");
473 uint old_unique_count = C->unique();
474 uint live_node_count = C->live_nodes();
475 uint worklist_size = worklist->size();
477 // Storage for the updated type information.
478 Type_Array new_type_array(C->comp_arena());
480 // Iterate over the set of live nodes.
481 uint current_idx = 0; // The current new node ID. Incremented after every assignment.
482 for (uint i = 0; i < _useful.size(); i++) {
483 Node* n = _useful.at(i);
484 const Type* type = gvn->type_or_null(n);
485 new_type_array.map(current_idx, type);
487 bool in_worklist = false;
488 if (worklist->member(n)) {
489 in_worklist = true;
490 }
492 n->set_idx(current_idx); // Update node ID.
494 if (in_worklist) {
495 new_worklist->push(n);
496 }
498 current_idx++;
499 }
501 assert(worklist_size == new_worklist->size(), "the new worklist must have the same size as the original worklist");
502 assert(live_node_count == current_idx, "all live nodes must be processed");
504 // Replace the compiler's type information with the updated type information.
505 gvn->replace_types(new_type_array);
507 // Update the unique node count of the compilation to the number of currently live nodes.
508 C->set_unique(live_node_count);
510 // Set the dead node count to 0 and reset dead node list.
511 C->reset_dead_node_list();
512 }
515 //=============================================================================
516 //------------------------------PhaseTransform---------------------------------
517 PhaseTransform::PhaseTransform( PhaseNumber pnum ) : Phase(pnum),
518 _arena(Thread::current()->resource_area()),
519 _nodes(_arena),
520 _types(_arena)
521 {
522 init_con_caches();
523 #ifndef PRODUCT
524 clear_progress();
525 clear_transforms();
526 set_allow_progress(true);
527 #endif
528 // Force allocation for currently existing nodes
529 _types.map(C->unique(), NULL);
530 }
532 //------------------------------PhaseTransform---------------------------------
533 PhaseTransform::PhaseTransform( Arena *arena, PhaseNumber pnum ) : Phase(pnum),
534 _arena(arena),
535 _nodes(arena),
536 _types(arena)
537 {
538 init_con_caches();
539 #ifndef PRODUCT
540 clear_progress();
541 clear_transforms();
542 set_allow_progress(true);
543 #endif
544 // Force allocation for currently existing nodes
545 _types.map(C->unique(), NULL);
546 }
548 //------------------------------PhaseTransform---------------------------------
549 // Initialize with previously generated type information
550 PhaseTransform::PhaseTransform( PhaseTransform *pt, PhaseNumber pnum ) : Phase(pnum),
551 _arena(pt->_arena),
552 _nodes(pt->_nodes),
553 _types(pt->_types)
554 {
555 init_con_caches();
556 #ifndef PRODUCT
557 clear_progress();
558 clear_transforms();
559 set_allow_progress(true);
560 #endif
561 }
563 void PhaseTransform::init_con_caches() {
564 memset(_icons,0,sizeof(_icons));
565 memset(_lcons,0,sizeof(_lcons));
566 memset(_zcons,0,sizeof(_zcons));
567 }
570 //--------------------------------find_int_type--------------------------------
571 const TypeInt* PhaseTransform::find_int_type(Node* n) {
572 if (n == NULL) return NULL;
573 // Call type_or_null(n) to determine node's type since we might be in
574 // parse phase and call n->Value() may return wrong type.
575 // (For example, a phi node at the beginning of loop parsing is not ready.)
576 const Type* t = type_or_null(n);
577 if (t == NULL) return NULL;
578 return t->isa_int();
579 }
582 //-------------------------------find_long_type--------------------------------
583 const TypeLong* PhaseTransform::find_long_type(Node* n) {
584 if (n == NULL) return NULL;
585 // (See comment above on type_or_null.)
586 const Type* t = type_or_null(n);
587 if (t == NULL) return NULL;
588 return t->isa_long();
589 }
592 #ifndef PRODUCT
593 void PhaseTransform::dump_old2new_map() const {
594 _nodes.dump();
595 }
597 void PhaseTransform::dump_new( uint nidx ) const {
598 for( uint i=0; i<_nodes.Size(); i++ )
599 if( _nodes[i] && _nodes[i]->_idx == nidx ) {
600 _nodes[i]->dump();
601 tty->cr();
602 tty->print_cr("Old index= %d",i);
603 return;
604 }
605 tty->print_cr("Node %d not found in the new indices", nidx);
606 }
608 //------------------------------dump_types-------------------------------------
609 void PhaseTransform::dump_types( ) const {
610 _types.dump();
611 }
613 //------------------------------dump_nodes_and_types---------------------------
614 void PhaseTransform::dump_nodes_and_types(const Node *root, uint depth, bool only_ctrl) {
615 VectorSet visited(Thread::current()->resource_area());
616 dump_nodes_and_types_recur( root, depth, only_ctrl, visited );
617 }
619 //------------------------------dump_nodes_and_types_recur---------------------
620 void PhaseTransform::dump_nodes_and_types_recur( const Node *n, uint depth, bool only_ctrl, VectorSet &visited) {
621 if( !n ) return;
622 if( depth == 0 ) return;
623 if( visited.test_set(n->_idx) ) return;
624 for( uint i=0; i<n->len(); i++ ) {
625 if( only_ctrl && !(n->is_Region()) && i != TypeFunc::Control ) continue;
626 dump_nodes_and_types_recur( n->in(i), depth-1, only_ctrl, visited );
627 }
628 n->dump();
629 if (type_or_null(n) != NULL) {
630 tty->print(" "); type(n)->dump(); tty->cr();
631 }
632 }
634 #endif
637 //=============================================================================
638 //------------------------------PhaseValues------------------------------------
639 // Set minimum table size to "255"
640 PhaseValues::PhaseValues( Arena *arena, uint est_max_size ) : PhaseTransform(arena, GVN), _table(arena, est_max_size) {
641 NOT_PRODUCT( clear_new_values(); )
642 }
644 //------------------------------PhaseValues------------------------------------
645 // Set minimum table size to "255"
646 PhaseValues::PhaseValues( PhaseValues *ptv ) : PhaseTransform( ptv, GVN ),
647 _table(&ptv->_table) {
648 NOT_PRODUCT( clear_new_values(); )
649 }
651 //------------------------------PhaseValues------------------------------------
652 // Used by +VerifyOpto. Clear out hash table but copy _types array.
653 PhaseValues::PhaseValues( PhaseValues *ptv, const char *dummy ) : PhaseTransform( ptv, GVN ),
654 _table(ptv->arena(),ptv->_table.size()) {
655 NOT_PRODUCT( clear_new_values(); )
656 }
658 //------------------------------~PhaseValues-----------------------------------
659 #ifndef PRODUCT
660 PhaseValues::~PhaseValues() {
661 _table.dump();
663 // Statistics for value progress and efficiency
664 if( PrintCompilation && Verbose && WizardMode ) {
665 tty->print("\n%sValues: %d nodes ---> %d/%d (%d)",
666 is_IterGVN() ? "Iter" : " ", C->unique(), made_progress(), made_transforms(), made_new_values());
667 if( made_transforms() != 0 ) {
668 tty->print_cr(" ratio %f", made_progress()/(float)made_transforms() );
669 } else {
670 tty->cr();
671 }
672 }
673 }
674 #endif
676 //------------------------------makecon----------------------------------------
677 ConNode* PhaseTransform::makecon(const Type *t) {
678 assert(t->singleton(), "must be a constant");
679 assert(!t->empty() || t == Type::TOP, "must not be vacuous range");
680 switch (t->base()) { // fast paths
681 case Type::Half:
682 case Type::Top: return (ConNode*) C->top();
683 case Type::Int: return intcon( t->is_int()->get_con() );
684 case Type::Long: return longcon( t->is_long()->get_con() );
685 }
686 if (t->is_zero_type())
687 return zerocon(t->basic_type());
688 return uncached_makecon(t);
689 }
691 //--------------------------uncached_makecon-----------------------------------
692 // Make an idealized constant - one of ConINode, ConPNode, etc.
693 ConNode* PhaseValues::uncached_makecon(const Type *t) {
694 assert(t->singleton(), "must be a constant");
695 ConNode* x = ConNode::make(C, t);
696 ConNode* k = (ConNode*)hash_find_insert(x); // Value numbering
697 if (k == NULL) {
698 set_type(x, t); // Missed, provide type mapping
699 GrowableArray<Node_Notes*>* nna = C->node_note_array();
700 if (nna != NULL) {
701 Node_Notes* loc = C->locate_node_notes(nna, x->_idx, true);
702 loc->clear(); // do not put debug info on constants
703 }
704 } else {
705 x->destruct(); // Hit, destroy duplicate constant
706 x = k; // use existing constant
707 }
708 return x;
709 }
711 //------------------------------intcon-----------------------------------------
712 // Fast integer constant. Same as "transform(new ConINode(TypeInt::make(i)))"
713 ConINode* PhaseTransform::intcon(int i) {
714 // Small integer? Check cache! Check that cached node is not dead
715 if (i >= _icon_min && i <= _icon_max) {
716 ConINode* icon = _icons[i-_icon_min];
717 if (icon != NULL && icon->in(TypeFunc::Control) != NULL)
718 return icon;
719 }
720 ConINode* icon = (ConINode*) uncached_makecon(TypeInt::make(i));
721 assert(icon->is_Con(), "");
722 if (i >= _icon_min && i <= _icon_max)
723 _icons[i-_icon_min] = icon; // Cache small integers
724 return icon;
725 }
727 //------------------------------longcon----------------------------------------
728 // Fast long constant.
729 ConLNode* PhaseTransform::longcon(jlong l) {
730 // Small integer? Check cache! Check that cached node is not dead
731 if (l >= _lcon_min && l <= _lcon_max) {
732 ConLNode* lcon = _lcons[l-_lcon_min];
733 if (lcon != NULL && lcon->in(TypeFunc::Control) != NULL)
734 return lcon;
735 }
736 ConLNode* lcon = (ConLNode*) uncached_makecon(TypeLong::make(l));
737 assert(lcon->is_Con(), "");
738 if (l >= _lcon_min && l <= _lcon_max)
739 _lcons[l-_lcon_min] = lcon; // Cache small integers
740 return lcon;
741 }
743 //------------------------------zerocon-----------------------------------------
744 // Fast zero or null constant. Same as "transform(ConNode::make(Type::get_zero_type(bt)))"
745 ConNode* PhaseTransform::zerocon(BasicType bt) {
746 assert((uint)bt <= _zcon_max, "domain check");
747 ConNode* zcon = _zcons[bt];
748 if (zcon != NULL && zcon->in(TypeFunc::Control) != NULL)
749 return zcon;
750 zcon = (ConNode*) uncached_makecon(Type::get_zero_type(bt));
751 _zcons[bt] = zcon;
752 return zcon;
753 }
757 //=============================================================================
758 //------------------------------transform--------------------------------------
759 // Return a node which computes the same function as this node, but in a
760 // faster or cheaper fashion.
761 Node *PhaseGVN::transform( Node *n ) {
762 return transform_no_reclaim(n);
763 }
765 //------------------------------transform--------------------------------------
766 // Return a node which computes the same function as this node, but
767 // in a faster or cheaper fashion.
768 Node *PhaseGVN::transform_no_reclaim( Node *n ) {
769 NOT_PRODUCT( set_transforms(); )
771 // Apply the Ideal call in a loop until it no longer applies
772 Node *k = n;
773 NOT_PRODUCT( uint loop_count = 0; )
774 while( 1 ) {
775 Node *i = k->Ideal(this, /*can_reshape=*/false);
776 if( !i ) break;
777 assert( i->_idx >= k->_idx, "Idealize should return new nodes, use Identity to return old nodes" );
778 k = i;
779 assert(loop_count++ < K, "infinite loop in PhaseGVN::transform");
780 }
781 NOT_PRODUCT( if( loop_count != 0 ) { set_progress(); } )
784 // If brand new node, make space in type array.
785 ensure_type_or_null(k);
787 // Since I just called 'Value' to compute the set of run-time values
788 // for this Node, and 'Value' is non-local (and therefore expensive) I'll
789 // cache Value. Later requests for the local phase->type of this Node can
790 // use the cached Value instead of suffering with 'bottom_type'.
791 const Type *t = k->Value(this); // Get runtime Value set
792 assert(t != NULL, "value sanity");
793 if (type_or_null(k) != t) {
794 #ifndef PRODUCT
795 // Do not count initial visit to node as a transformation
796 if (type_or_null(k) == NULL) {
797 inc_new_values();
798 set_progress();
799 }
800 #endif
801 set_type(k, t);
802 // If k is a TypeNode, capture any more-precise type permanently into Node
803 k->raise_bottom_type(t);
804 }
806 if( t->singleton() && !k->is_Con() ) {
807 NOT_PRODUCT( set_progress(); )
808 return makecon(t); // Turn into a constant
809 }
811 // Now check for Identities
812 Node *i = k->Identity(this); // Look for a nearby replacement
813 if( i != k ) { // Found? Return replacement!
814 NOT_PRODUCT( set_progress(); )
815 return i;
816 }
818 // Global Value Numbering
819 i = hash_find_insert(k); // Insert if new
820 if( i && (i != k) ) {
821 // Return the pre-existing node
822 NOT_PRODUCT( set_progress(); )
823 return i;
824 }
826 // Return Idealized original
827 return k;
828 }
830 #ifdef ASSERT
831 //------------------------------dead_loop_check--------------------------------
832 // Check for a simple dead loop when a data node references itself directly
833 // or through an other data node excluding cons and phis.
834 void PhaseGVN::dead_loop_check( Node *n ) {
835 // Phi may reference itself in a loop
836 if (n != NULL && !n->is_dead_loop_safe() && !n->is_CFG()) {
837 // Do 2 levels check and only data inputs.
838 bool no_dead_loop = true;
839 uint cnt = n->req();
840 for (uint i = 1; i < cnt && no_dead_loop; i++) {
841 Node *in = n->in(i);
842 if (in == n) {
843 no_dead_loop = false;
844 } else if (in != NULL && !in->is_dead_loop_safe()) {
845 uint icnt = in->req();
846 for (uint j = 1; j < icnt && no_dead_loop; j++) {
847 if (in->in(j) == n || in->in(j) == in)
848 no_dead_loop = false;
849 }
850 }
851 }
852 if (!no_dead_loop) n->dump(3);
853 assert(no_dead_loop, "dead loop detected");
854 }
855 }
856 #endif
858 //=============================================================================
859 //------------------------------PhaseIterGVN-----------------------------------
860 // Initialize hash table to fresh and clean for +VerifyOpto
861 PhaseIterGVN::PhaseIterGVN( PhaseIterGVN *igvn, const char *dummy ) : PhaseGVN(igvn,dummy), _worklist( ),
862 _stack(C->live_nodes() >> 1),
863 _delay_transform(false) {
864 }
866 //------------------------------PhaseIterGVN-----------------------------------
867 // Initialize with previous PhaseIterGVN info; used by PhaseCCP
868 PhaseIterGVN::PhaseIterGVN( PhaseIterGVN *igvn ) : PhaseGVN(igvn),
869 _worklist( igvn->_worklist ),
870 _stack( igvn->_stack ),
871 _delay_transform(igvn->_delay_transform)
872 {
873 }
875 //------------------------------PhaseIterGVN-----------------------------------
876 // Initialize with previous PhaseGVN info from Parser
877 PhaseIterGVN::PhaseIterGVN( PhaseGVN *gvn ) : PhaseGVN(gvn),
878 _worklist(*C->for_igvn()),
879 // TODO: Before incremental inlining it was allocated only once and it was fine. Now that
880 // the constructor is used in incremental inlining, this consumes too much memory:
881 // _stack(C->live_nodes() >> 1),
882 // So, as a band-aid, we replace this by:
883 _stack(C->comp_arena(), 32),
884 _delay_transform(false)
885 {
886 uint max;
888 // Dead nodes in the hash table inherited from GVN were not treated as
889 // roots during def-use info creation; hence they represent an invisible
890 // use. Clear them out.
891 max = _table.size();
892 for( uint i = 0; i < max; ++i ) {
893 Node *n = _table.at(i);
894 if(n != NULL && n != _table.sentinel() && n->outcnt() == 0) {
895 if( n->is_top() ) continue;
896 assert( false, "Parse::remove_useless_nodes missed this node");
897 hash_delete(n);
898 }
899 }
901 // Any Phis or Regions on the worklist probably had uses that could not
902 // make more progress because the uses were made while the Phis and Regions
903 // were in half-built states. Put all uses of Phis and Regions on worklist.
904 max = _worklist.size();
905 for( uint j = 0; j < max; j++ ) {
906 Node *n = _worklist.at(j);
907 uint uop = n->Opcode();
908 if( uop == Op_Phi || uop == Op_Region ||
909 n->is_Type() ||
910 n->is_Mem() )
911 add_users_to_worklist(n);
912 }
913 }
916 #ifndef PRODUCT
917 void PhaseIterGVN::verify_step(Node* n) {
918 _verify_window[_verify_counter % _verify_window_size] = n;
919 ++_verify_counter;
920 ResourceMark rm;
921 ResourceArea *area = Thread::current()->resource_area();
922 VectorSet old_space(area), new_space(area);
923 if (C->unique() < 1000 ||
924 0 == _verify_counter % (C->unique() < 10000 ? 10 : 100)) {
925 ++_verify_full_passes;
926 Node::verify_recur(C->root(), -1, old_space, new_space);
927 }
928 const int verify_depth = 4;
929 for ( int i = 0; i < _verify_window_size; i++ ) {
930 Node* n = _verify_window[i];
931 if ( n == NULL ) continue;
932 if( n->in(0) == NodeSentinel ) { // xform_idom
933 _verify_window[i] = n->in(1);
934 --i; continue;
935 }
936 // Typical fanout is 1-2, so this call visits about 6 nodes.
937 Node::verify_recur(n, verify_depth, old_space, new_space);
938 }
939 }
940 #endif
943 //------------------------------init_worklist----------------------------------
944 // Initialize worklist for each node.
945 void PhaseIterGVN::init_worklist( Node *n ) {
946 if( _worklist.member(n) ) return;
947 _worklist.push(n);
948 uint cnt = n->req();
949 for( uint i =0 ; i < cnt; i++ ) {
950 Node *m = n->in(i);
951 if( m ) init_worklist(m);
952 }
953 }
955 //------------------------------optimize---------------------------------------
956 void PhaseIterGVN::optimize() {
957 debug_only(uint num_processed = 0;);
958 #ifndef PRODUCT
959 {
960 _verify_counter = 0;
961 _verify_full_passes = 0;
962 for ( int i = 0; i < _verify_window_size; i++ ) {
963 _verify_window[i] = NULL;
964 }
965 }
966 #endif
968 #ifdef ASSERT
969 Node* prev = NULL;
970 uint rep_cnt = 0;
971 #endif
972 uint loop_count = 0;
974 // Pull from worklist; transform node;
975 // If node has changed: update edge info and put uses on worklist.
976 while( _worklist.size() ) {
977 if (C->check_node_count(NodeLimitFudgeFactor * 2,
978 "out of nodes optimizing method")) {
979 return;
980 }
981 Node *n = _worklist.pop();
982 if (++loop_count >= K * C->live_nodes()) {
983 debug_only(n->dump(4);)
984 assert(false, "infinite loop in PhaseIterGVN::optimize");
985 C->record_method_not_compilable("infinite loop in PhaseIterGVN::optimize");
986 return;
987 }
988 #ifdef ASSERT
989 if (n == prev) {
990 if (++rep_cnt > 3) {
991 n->dump(4);
992 assert(false, "loop in Ideal transformation");
993 }
994 } else {
995 rep_cnt = 0;
996 }
997 prev = n;
998 #endif
999 if (TraceIterativeGVN && Verbose) {
1000 tty->print(" Pop ");
1001 NOT_PRODUCT( n->dump(); )
1002 debug_only(if( (num_processed++ % 100) == 0 ) _worklist.print_set();)
1003 }
1005 if (n->outcnt() != 0) {
1007 #ifndef PRODUCT
1008 uint wlsize = _worklist.size();
1009 const Type* oldtype = type_or_null(n);
1010 #endif //PRODUCT
1012 Node *nn = transform_old(n);
1014 #ifndef PRODUCT
1015 if (TraceIterativeGVN) {
1016 const Type* newtype = type_or_null(n);
1017 if (nn != n) {
1018 // print old node
1019 tty->print("< ");
1020 if (oldtype != newtype && oldtype != NULL) {
1021 oldtype->dump();
1022 }
1023 do { tty->print("\t"); } while (tty->position() < 16);
1024 tty->print("<");
1025 n->dump();
1026 }
1027 if (oldtype != newtype || nn != n) {
1028 // print new node and/or new type
1029 if (oldtype == NULL) {
1030 tty->print("* ");
1031 } else if (nn != n) {
1032 tty->print("> ");
1033 } else {
1034 tty->print("= ");
1035 }
1036 if (newtype == NULL) {
1037 tty->print("null");
1038 } else {
1039 newtype->dump();
1040 }
1041 do { tty->print("\t"); } while (tty->position() < 16);
1042 nn->dump();
1043 }
1044 if (Verbose && wlsize < _worklist.size()) {
1045 tty->print(" Push {");
1046 while (wlsize != _worklist.size()) {
1047 Node* pushed = _worklist.at(wlsize++);
1048 tty->print(" %d", pushed->_idx);
1049 }
1050 tty->print_cr(" }");
1051 }
1052 }
1053 if( VerifyIterativeGVN && nn != n ) {
1054 verify_step((Node*) NULL); // ignore n, it might be subsumed
1055 }
1056 #endif
1057 } else if (!n->is_top()) {
1058 remove_dead_node(n);
1059 }
1060 }
1062 #ifndef PRODUCT
1063 C->verify_graph_edges();
1064 if( VerifyOpto && allow_progress() ) {
1065 // Must turn off allow_progress to enable assert and break recursion
1066 C->root()->verify();
1067 { // Check if any progress was missed using IterGVN
1068 // Def-Use info enables transformations not attempted in wash-pass
1069 // e.g. Region/Phi cleanup, ...
1070 // Null-check elision -- may not have reached fixpoint
1071 // do not propagate to dominated nodes
1072 ResourceMark rm;
1073 PhaseIterGVN igvn2(this,"Verify"); // Fresh and clean!
1074 // Fill worklist completely
1075 igvn2.init_worklist(C->root());
1077 igvn2.set_allow_progress(false);
1078 igvn2.optimize();
1079 igvn2.set_allow_progress(true);
1080 }
1081 }
1082 if ( VerifyIterativeGVN && PrintOpto ) {
1083 if ( _verify_counter == _verify_full_passes )
1084 tty->print_cr("VerifyIterativeGVN: %d transforms and verify passes",
1085 (int) _verify_full_passes);
1086 else
1087 tty->print_cr("VerifyIterativeGVN: %d transforms, %d full verify passes",
1088 (int) _verify_counter, (int) _verify_full_passes);
1089 }
1090 #endif
1091 }
1094 //------------------register_new_node_with_optimizer---------------------------
1095 // Register a new node with the optimizer. Update the types array, the def-use
1096 // info. Put on worklist.
1097 Node* PhaseIterGVN::register_new_node_with_optimizer(Node* n, Node* orig) {
1098 set_type_bottom(n);
1099 _worklist.push(n);
1100 if (orig != NULL) C->copy_node_notes_to(n, orig);
1101 return n;
1102 }
1104 //------------------------------transform--------------------------------------
1105 // Non-recursive: idealize Node 'n' with respect to its inputs and its value
1106 Node *PhaseIterGVN::transform( Node *n ) {
1107 if (_delay_transform) {
1108 // Register the node but don't optimize for now
1109 register_new_node_with_optimizer(n);
1110 return n;
1111 }
1113 // If brand new node, make space in type array, and give it a type.
1114 ensure_type_or_null(n);
1115 if (type_or_null(n) == NULL) {
1116 set_type_bottom(n);
1117 }
1119 return transform_old(n);
1120 }
1122 //------------------------------transform_old----------------------------------
1123 Node *PhaseIterGVN::transform_old( Node *n ) {
1124 #ifndef PRODUCT
1125 debug_only(uint loop_count = 0;);
1126 set_transforms();
1127 #endif
1128 // Remove 'n' from hash table in case it gets modified
1129 _table.hash_delete(n);
1130 if( VerifyIterativeGVN ) {
1131 assert( !_table.find_index(n->_idx), "found duplicate entry in table");
1132 }
1134 // Apply the Ideal call in a loop until it no longer applies
1135 Node *k = n;
1136 DEBUG_ONLY(dead_loop_check(k);)
1137 DEBUG_ONLY(bool is_new = (k->outcnt() == 0);)
1138 Node *i = k->Ideal(this, /*can_reshape=*/true);
1139 assert(i != k || is_new || i->outcnt() > 0, "don't return dead nodes");
1140 #ifndef PRODUCT
1141 if( VerifyIterativeGVN )
1142 verify_step(k);
1143 if( i && VerifyOpto ) {
1144 if( !allow_progress() ) {
1145 if (i->is_Add() && i->outcnt() == 1) {
1146 // Switched input to left side because this is the only use
1147 } else if( i->is_If() && (i->in(0) == NULL) ) {
1148 // This IF is dead because it is dominated by an equivalent IF When
1149 // dominating if changed, info is not propagated sparsely to 'this'
1150 // Propagating this info further will spuriously identify other
1151 // progress.
1152 return i;
1153 } else
1154 set_progress();
1155 } else
1156 set_progress();
1157 }
1158 #endif
1160 while( i ) {
1161 #ifndef PRODUCT
1162 debug_only( if( loop_count >= K ) i->dump(4); )
1163 assert(loop_count < K, "infinite loop in PhaseIterGVN::transform");
1164 debug_only( loop_count++; )
1165 #endif
1166 assert((i->_idx >= k->_idx) || i->is_top(), "Idealize should return new nodes, use Identity to return old nodes");
1167 // Made a change; put users of original Node on worklist
1168 add_users_to_worklist( k );
1169 // Replacing root of transform tree?
1170 if( k != i ) {
1171 // Make users of old Node now use new.
1172 subsume_node( k, i );
1173 k = i;
1174 }
1175 DEBUG_ONLY(dead_loop_check(k);)
1176 // Try idealizing again
1177 DEBUG_ONLY(is_new = (k->outcnt() == 0);)
1178 i = k->Ideal(this, /*can_reshape=*/true);
1179 assert(i != k || is_new || i->outcnt() > 0, "don't return dead nodes");
1180 #ifndef PRODUCT
1181 if( VerifyIterativeGVN )
1182 verify_step(k);
1183 if( i && VerifyOpto ) set_progress();
1184 #endif
1185 }
1187 // If brand new node, make space in type array.
1188 ensure_type_or_null(k);
1190 // See what kind of values 'k' takes on at runtime
1191 const Type *t = k->Value(this);
1192 assert(t != NULL, "value sanity");
1194 // Since I just called 'Value' to compute the set of run-time values
1195 // for this Node, and 'Value' is non-local (and therefore expensive) I'll
1196 // cache Value. Later requests for the local phase->type of this Node can
1197 // use the cached Value instead of suffering with 'bottom_type'.
1198 if (t != type_or_null(k)) {
1199 NOT_PRODUCT( set_progress(); )
1200 NOT_PRODUCT( inc_new_values();)
1201 set_type(k, t);
1202 // If k is a TypeNode, capture any more-precise type permanently into Node
1203 k->raise_bottom_type(t);
1204 // Move users of node to worklist
1205 add_users_to_worklist( k );
1206 }
1208 // If 'k' computes a constant, replace it with a constant
1209 if( t->singleton() && !k->is_Con() ) {
1210 NOT_PRODUCT( set_progress(); )
1211 Node *con = makecon(t); // Make a constant
1212 add_users_to_worklist( k );
1213 subsume_node( k, con ); // Everybody using k now uses con
1214 return con;
1215 }
1217 // Now check for Identities
1218 i = k->Identity(this); // Look for a nearby replacement
1219 if( i != k ) { // Found? Return replacement!
1220 NOT_PRODUCT( set_progress(); )
1221 add_users_to_worklist( k );
1222 subsume_node( k, i ); // Everybody using k now uses i
1223 return i;
1224 }
1226 // Global Value Numbering
1227 i = hash_find_insert(k); // Check for pre-existing node
1228 if( i && (i != k) ) {
1229 // Return the pre-existing node if it isn't dead
1230 NOT_PRODUCT( set_progress(); )
1231 add_users_to_worklist( k );
1232 subsume_node( k, i ); // Everybody using k now uses i
1233 return i;
1234 }
1236 // Return Idealized original
1237 return k;
1238 }
1240 //---------------------------------saturate------------------------------------
1241 const Type* PhaseIterGVN::saturate(const Type* new_type, const Type* old_type,
1242 const Type* limit_type) const {
1243 return new_type->narrow(old_type);
1244 }
1246 //------------------------------remove_globally_dead_node----------------------
1247 // Kill a globally dead Node. All uses are also globally dead and are
1248 // aggressively trimmed.
1249 void PhaseIterGVN::remove_globally_dead_node( Node *dead ) {
1250 enum DeleteProgress {
1251 PROCESS_INPUTS,
1252 PROCESS_OUTPUTS
1253 };
1254 assert(_stack.is_empty(), "not empty");
1255 _stack.push(dead, PROCESS_INPUTS);
1257 while (_stack.is_nonempty()) {
1258 dead = _stack.node();
1259 uint progress_state = _stack.index();
1260 assert(dead != C->root(), "killing root, eh?");
1261 assert(!dead->is_top(), "add check for top when pushing");
1262 NOT_PRODUCT( set_progress(); )
1263 if (progress_state == PROCESS_INPUTS) {
1264 // After following inputs, continue to outputs
1265 _stack.set_index(PROCESS_OUTPUTS);
1266 if (!dead->is_Con()) { // Don't kill cons but uses
1267 bool recurse = false;
1268 // Remove from hash table
1269 _table.hash_delete( dead );
1270 // Smash all inputs to 'dead', isolating him completely
1271 for (uint i = 0; i < dead->req(); i++) {
1272 Node *in = dead->in(i);
1273 if (in != NULL && in != C->top()) { // Points to something?
1274 int nrep = dead->replace_edge(in, NULL); // Kill edges
1275 assert((nrep > 0), "sanity");
1276 if (in->outcnt() == 0) { // Made input go dead?
1277 _stack.push(in, PROCESS_INPUTS); // Recursively remove
1278 recurse = true;
1279 } else if (in->outcnt() == 1 &&
1280 in->has_special_unique_user()) {
1281 _worklist.push(in->unique_out());
1282 } else if (in->outcnt() <= 2 && dead->is_Phi()) {
1283 if (in->Opcode() == Op_Region) {
1284 _worklist.push(in);
1285 } else if (in->is_Store()) {
1286 DUIterator_Fast imax, i = in->fast_outs(imax);
1287 _worklist.push(in->fast_out(i));
1288 i++;
1289 if (in->outcnt() == 2) {
1290 _worklist.push(in->fast_out(i));
1291 i++;
1292 }
1293 assert(!(i < imax), "sanity");
1294 }
1295 }
1296 if (ReduceFieldZeroing && dead->is_Load() && i == MemNode::Memory &&
1297 in->is_Proj() && in->in(0) != NULL && in->in(0)->is_Initialize()) {
1298 // A Load that directly follows an InitializeNode is
1299 // going away. The Stores that follow are candidates
1300 // again to be captured by the InitializeNode.
1301 for (DUIterator_Fast jmax, j = in->fast_outs(jmax); j < jmax; j++) {
1302 Node *n = in->fast_out(j);
1303 if (n->is_Store()) {
1304 _worklist.push(n);
1305 }
1306 }
1307 }
1308 } // if (in != NULL && in != C->top())
1309 } // for (uint i = 0; i < dead->req(); i++)
1310 if (recurse) {
1311 continue;
1312 }
1313 } // if (!dead->is_Con())
1314 } // if (progress_state == PROCESS_INPUTS)
1316 // Aggressively kill globally dead uses
1317 // (Rather than pushing all the outs at once, we push one at a time,
1318 // plus the parent to resume later, because of the indefinite number
1319 // of edge deletions per loop trip.)
1320 if (dead->outcnt() > 0) {
1321 // Recursively remove output edges
1322 _stack.push(dead->raw_out(0), PROCESS_INPUTS);
1323 } else {
1324 // Finished disconnecting all input and output edges.
1325 _stack.pop();
1326 // Remove dead node from iterative worklist
1327 _worklist.remove(dead);
1328 // Constant node that has no out-edges and has only one in-edge from
1329 // root is usually dead. However, sometimes reshaping walk makes
1330 // it reachable by adding use edges. So, we will NOT count Con nodes
1331 // as dead to be conservative about the dead node count at any
1332 // given time.
1333 if (!dead->is_Con()) {
1334 C->record_dead_node(dead->_idx);
1335 }
1336 if (dead->is_macro()) {
1337 C->remove_macro_node(dead);
1338 }
1339 if (dead->is_expensive()) {
1340 C->remove_expensive_node(dead);
1341 }
1342 CastIINode* cast = dead->isa_CastII();
1343 if (cast != NULL && cast->has_range_check()) {
1344 C->remove_range_check_cast(cast);
1345 }
1346 }
1347 } // while (_stack.is_nonempty())
1348 }
1350 //------------------------------subsume_node-----------------------------------
1351 // Remove users from node 'old' and add them to node 'nn'.
1352 void PhaseIterGVN::subsume_node( Node *old, Node *nn ) {
1353 assert( old != hash_find(old), "should already been removed" );
1354 assert( old != C->top(), "cannot subsume top node");
1355 // Copy debug or profile information to the new version:
1356 C->copy_node_notes_to(nn, old);
1357 // Move users of node 'old' to node 'nn'
1358 for (DUIterator_Last imin, i = old->last_outs(imin); i >= imin; ) {
1359 Node* use = old->last_out(i); // for each use...
1360 // use might need re-hashing (but it won't if it's a new node)
1361 bool is_in_table = _table.hash_delete( use );
1362 // Update use-def info as well
1363 // We remove all occurrences of old within use->in,
1364 // so as to avoid rehashing any node more than once.
1365 // The hash table probe swamps any outer loop overhead.
1366 uint num_edges = 0;
1367 for (uint jmax = use->len(), j = 0; j < jmax; j++) {
1368 if (use->in(j) == old) {
1369 use->set_req(j, nn);
1370 ++num_edges;
1371 }
1372 }
1373 // Insert into GVN hash table if unique
1374 // If a duplicate, 'use' will be cleaned up when pulled off worklist
1375 if( is_in_table ) {
1376 hash_find_insert(use);
1377 }
1378 i -= num_edges; // we deleted 1 or more copies of this edge
1379 }
1381 // Smash all inputs to 'old', isolating him completely
1382 Node *temp = new (C) Node(1);
1383 temp->init_req(0,nn); // Add a use to nn to prevent him from dying
1384 remove_dead_node( old );
1385 temp->del_req(0); // Yank bogus edge
1386 #ifndef PRODUCT
1387 if( VerifyIterativeGVN ) {
1388 for ( int i = 0; i < _verify_window_size; i++ ) {
1389 if ( _verify_window[i] == old )
1390 _verify_window[i] = nn;
1391 }
1392 }
1393 #endif
1394 _worklist.remove(temp); // this can be necessary
1395 temp->destruct(); // reuse the _idx of this little guy
1396 }
1398 //------------------------------add_users_to_worklist--------------------------
1399 void PhaseIterGVN::add_users_to_worklist0( Node *n ) {
1400 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1401 _worklist.push(n->fast_out(i)); // Push on worklist
1402 }
1403 }
1405 void PhaseIterGVN::add_users_to_worklist( Node *n ) {
1406 add_users_to_worklist0(n);
1408 // Move users of node to worklist
1409 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1410 Node* use = n->fast_out(i); // Get use
1412 if( use->is_Multi() || // Multi-definer? Push projs on worklist
1413 use->is_Store() ) // Enable store/load same address
1414 add_users_to_worklist0(use);
1416 // If we changed the receiver type to a call, we need to revisit
1417 // the Catch following the call. It's looking for a non-NULL
1418 // receiver to know when to enable the regular fall-through path
1419 // in addition to the NullPtrException path.
1420 if (use->is_CallDynamicJava() && n == use->in(TypeFunc::Parms)) {
1421 Node* p = use->as_CallDynamicJava()->proj_out(TypeFunc::Control);
1422 if (p != NULL) {
1423 add_users_to_worklist0(p);
1424 }
1425 }
1427 uint use_op = use->Opcode();
1428 if(use->is_Cmp()) { // Enable CMP/BOOL optimization
1429 add_users_to_worklist(use); // Put Bool on worklist
1430 if (use->outcnt() > 0) {
1431 Node* bol = use->raw_out(0);
1432 if (bol->outcnt() > 0) {
1433 Node* iff = bol->raw_out(0);
1434 if (use_op == Op_CmpI &&
1435 iff->is_CountedLoopEnd()) {
1436 CountedLoopEndNode* cle = iff->as_CountedLoopEnd();
1437 if (cle->limit() == n && cle->phi() != NULL) {
1438 // If an opaque node feeds into the limit condition of a
1439 // CountedLoop, we need to process the Phi node for the
1440 // induction variable when the opaque node is removed:
1441 // the range of values taken by the Phi is now known and
1442 // so its type is also known.
1443 _worklist.push(cle->phi());
1444 }
1445 } else if (iff->outcnt() == 2) {
1446 // Look for the 'is_x2logic' pattern: "x ? : 0 : 1" and put the
1447 // phi merging either 0 or 1 onto the worklist
1448 Node* ifproj0 = iff->raw_out(0);
1449 Node* ifproj1 = iff->raw_out(1);
1450 if (ifproj0->outcnt() > 0 && ifproj1->outcnt() > 0) {
1451 Node* region0 = ifproj0->raw_out(0);
1452 Node* region1 = ifproj1->raw_out(0);
1453 if( region0 == region1 )
1454 add_users_to_worklist0(region0);
1455 }
1456 }
1457 }
1458 }
1459 if (use_op == Op_CmpI) {
1460 Node* in1 = use->in(1);
1461 for (uint i = 0; i < in1->outcnt(); i++) {
1462 if (in1->raw_out(i)->Opcode() == Op_CastII) {
1463 Node* castii = in1->raw_out(i);
1464 if (castii->in(0) != NULL && castii->in(0)->in(0) != NULL && castii->in(0)->in(0)->is_If()) {
1465 Node* ifnode = castii->in(0)->in(0);
1466 if (ifnode->in(1) != NULL && ifnode->in(1)->is_Bool() && ifnode->in(1)->in(1) == use) {
1467 // Reprocess a CastII node that may depend on an
1468 // opaque node value when the opaque node is
1469 // removed. In case it carries a dependency we can do
1470 // a better job of computing its type.
1471 _worklist.push(castii);
1472 }
1473 }
1474 }
1475 }
1476 }
1477 }
1479 // If changed Cast input, check Phi users for simple cycles
1480 if( use->is_ConstraintCast() || use->is_CheckCastPP() ) {
1481 for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
1482 Node* u = use->fast_out(i2);
1483 if (u->is_Phi())
1484 _worklist.push(u);
1485 }
1486 }
1487 // If changed LShift inputs, check RShift users for useless sign-ext
1488 if( use_op == Op_LShiftI ) {
1489 for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
1490 Node* u = use->fast_out(i2);
1491 if (u->Opcode() == Op_RShiftI)
1492 _worklist.push(u);
1493 }
1494 }
1495 // If changed AddI/SubI inputs, check CmpU for range check optimization.
1496 if (use_op == Op_AddI || use_op == Op_SubI) {
1497 for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
1498 Node* u = use->fast_out(i2);
1499 if (u->is_Cmp() && (u->Opcode() == Op_CmpU)) {
1500 _worklist.push(u);
1501 }
1502 }
1503 }
1504 // If changed AddP inputs, check Stores for loop invariant
1505 if( use_op == Op_AddP ) {
1506 for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
1507 Node* u = use->fast_out(i2);
1508 if (u->is_Mem())
1509 _worklist.push(u);
1510 }
1511 }
1512 // If changed initialization activity, check dependent Stores
1513 if (use_op == Op_Allocate || use_op == Op_AllocateArray) {
1514 InitializeNode* init = use->as_Allocate()->initialization();
1515 if (init != NULL) {
1516 Node* imem = init->proj_out(TypeFunc::Memory);
1517 if (imem != NULL) add_users_to_worklist0(imem);
1518 }
1519 }
1520 if (use_op == Op_Initialize) {
1521 Node* imem = use->as_Initialize()->proj_out(TypeFunc::Memory);
1522 if (imem != NULL) add_users_to_worklist0(imem);
1523 }
1524 }
1525 }
1527 /**
1528 * Remove the speculative part of all types that we know of
1529 */
1530 void PhaseIterGVN::remove_speculative_types() {
1531 assert(UseTypeSpeculation, "speculation is off");
1532 for (uint i = 0; i < _types.Size(); i++) {
1533 const Type* t = _types.fast_lookup(i);
1534 if (t != NULL) {
1535 _types.map(i, t->remove_speculative());
1536 }
1537 }
1538 _table.check_no_speculative_types();
1539 }
1541 //=============================================================================
1542 #ifndef PRODUCT
1543 uint PhaseCCP::_total_invokes = 0;
1544 uint PhaseCCP::_total_constants = 0;
1545 #endif
1546 //------------------------------PhaseCCP---------------------------------------
1547 // Conditional Constant Propagation, ala Wegman & Zadeck
1548 PhaseCCP::PhaseCCP( PhaseIterGVN *igvn ) : PhaseIterGVN(igvn) {
1549 NOT_PRODUCT( clear_constants(); )
1550 assert( _worklist.size() == 0, "" );
1551 // Clear out _nodes from IterGVN. Must be clear to transform call.
1552 _nodes.clear(); // Clear out from IterGVN
1553 analyze();
1554 }
1556 #ifndef PRODUCT
1557 //------------------------------~PhaseCCP--------------------------------------
1558 PhaseCCP::~PhaseCCP() {
1559 inc_invokes();
1560 _total_constants += count_constants();
1561 }
1562 #endif
1565 #ifdef ASSERT
1566 static bool ccp_type_widens(const Type* t, const Type* t0) {
1567 assert(t->meet(t0) == t, "Not monotonic");
1568 switch (t->base() == t0->base() ? t->base() : Type::Top) {
1569 case Type::Int:
1570 assert(t0->isa_int()->_widen <= t->isa_int()->_widen, "widen increases");
1571 break;
1572 case Type::Long:
1573 assert(t0->isa_long()->_widen <= t->isa_long()->_widen, "widen increases");
1574 break;
1575 }
1576 return true;
1577 }
1578 #endif //ASSERT
1580 //------------------------------analyze----------------------------------------
1581 void PhaseCCP::analyze() {
1582 // Initialize all types to TOP, optimistic analysis
1583 for (int i = C->unique() - 1; i >= 0; i--) {
1584 _types.map(i,Type::TOP);
1585 }
1587 // Push root onto worklist
1588 Unique_Node_List worklist;
1589 worklist.push(C->root());
1591 // Pull from worklist; compute new value; push changes out.
1592 // This loop is the meat of CCP.
1593 while( worklist.size() ) {
1594 Node *n = worklist.pop();
1595 const Type *t = n->Value(this);
1596 if (t != type(n)) {
1597 assert(ccp_type_widens(t, type(n)), "ccp type must widen");
1598 #ifndef PRODUCT
1599 if( TracePhaseCCP ) {
1600 t->dump();
1601 do { tty->print("\t"); } while (tty->position() < 16);
1602 n->dump();
1603 }
1604 #endif
1605 set_type(n, t);
1606 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1607 Node* m = n->fast_out(i); // Get user
1608 if (m->is_Region()) { // New path to Region? Must recheck Phis too
1609 for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
1610 Node* p = m->fast_out(i2); // Propagate changes to uses
1611 if (p->bottom_type() != type(p)) { // If not already bottomed out
1612 worklist.push(p); // Propagate change to user
1613 }
1614 }
1615 }
1616 // If we changed the receiver type to a call, we need to revisit
1617 // the Catch following the call. It's looking for a non-NULL
1618 // receiver to know when to enable the regular fall-through path
1619 // in addition to the NullPtrException path
1620 if (m->is_Call()) {
1621 for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
1622 Node* p = m->fast_out(i2); // Propagate changes to uses
1623 if (p->is_Proj() && p->as_Proj()->_con == TypeFunc::Control && p->outcnt() == 1) {
1624 worklist.push(p->unique_out());
1625 }
1626 }
1627 }
1628 if (m->bottom_type() != type(m)) { // If not already bottomed out
1629 worklist.push(m); // Propagate change to user
1630 }
1632 // CmpU nodes can get their type information from two nodes up in the
1633 // graph (instead of from the nodes immediately above). Make sure they
1634 // are added to the worklist if nodes they depend on are updated, since
1635 // they could be missed and get wrong types otherwise.
1636 uint m_op = m->Opcode();
1637 if (m_op == Op_AddI || m_op == Op_SubI) {
1638 for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
1639 Node* p = m->fast_out(i2); // Propagate changes to uses
1640 if (p->Opcode() == Op_CmpU) {
1641 // Got a CmpU which might need the new type information from node n.
1642 if(p->bottom_type() != type(p)) { // If not already bottomed out
1643 worklist.push(p); // Propagate change to user
1644 }
1645 }
1646 }
1647 }
1648 }
1649 }
1650 }
1651 }
1653 //------------------------------do_transform-----------------------------------
1654 // Top level driver for the recursive transformer
1655 void PhaseCCP::do_transform() {
1656 // Correct leaves of new-space Nodes; they point to old-space.
1657 C->set_root( transform(C->root())->as_Root() );
1658 assert( C->top(), "missing TOP node" );
1659 assert( C->root(), "missing root" );
1660 }
1662 //------------------------------transform--------------------------------------
1663 // Given a Node in old-space, clone him into new-space.
1664 // Convert any of his old-space children into new-space children.
1665 Node *PhaseCCP::transform( Node *n ) {
1666 Node *new_node = _nodes[n->_idx]; // Check for transformed node
1667 if( new_node != NULL )
1668 return new_node; // Been there, done that, return old answer
1669 new_node = transform_once(n); // Check for constant
1670 _nodes.map( n->_idx, new_node ); // Flag as having been cloned
1672 // Allocate stack of size _nodes.Size()/2 to avoid frequent realloc
1673 GrowableArray <Node *> trstack(C->live_nodes() >> 1);
1675 trstack.push(new_node); // Process children of cloned node
1676 while ( trstack.is_nonempty() ) {
1677 Node *clone = trstack.pop();
1678 uint cnt = clone->req();
1679 for( uint i = 0; i < cnt; i++ ) { // For all inputs do
1680 Node *input = clone->in(i);
1681 if( input != NULL ) { // Ignore NULLs
1682 Node *new_input = _nodes[input->_idx]; // Check for cloned input node
1683 if( new_input == NULL ) {
1684 new_input = transform_once(input); // Check for constant
1685 _nodes.map( input->_idx, new_input );// Flag as having been cloned
1686 trstack.push(new_input);
1687 }
1688 assert( new_input == clone->in(i), "insanity check");
1689 }
1690 }
1691 }
1692 return new_node;
1693 }
1696 //------------------------------transform_once---------------------------------
1697 // For PhaseCCP, transformation is IDENTITY unless Node computed a constant.
1698 Node *PhaseCCP::transform_once( Node *n ) {
1699 const Type *t = type(n);
1700 // Constant? Use constant Node instead
1701 if( t->singleton() ) {
1702 Node *nn = n; // Default is to return the original constant
1703 if( t == Type::TOP ) {
1704 // cache my top node on the Compile instance
1705 if( C->cached_top_node() == NULL || C->cached_top_node()->in(0) == NULL ) {
1706 C->set_cached_top_node( ConNode::make(C, Type::TOP) );
1707 set_type(C->top(), Type::TOP);
1708 }
1709 nn = C->top();
1710 }
1711 if( !n->is_Con() ) {
1712 if( t != Type::TOP ) {
1713 nn = makecon(t); // ConNode::make(t);
1714 NOT_PRODUCT( inc_constants(); )
1715 } else if( n->is_Region() ) { // Unreachable region
1716 // Note: nn == C->top()
1717 n->set_req(0, NULL); // Cut selfreference
1718 // Eagerly remove dead phis to avoid phis copies creation.
1719 for (DUIterator i = n->outs(); n->has_out(i); i++) {
1720 Node* m = n->out(i);
1721 if( m->is_Phi() ) {
1722 assert(type(m) == Type::TOP, "Unreachable region should not have live phis.");
1723 replace_node(m, nn);
1724 --i; // deleted this phi; rescan starting with next position
1725 }
1726 }
1727 }
1728 replace_node(n,nn); // Update DefUse edges for new constant
1729 }
1730 return nn;
1731 }
1733 // If x is a TypeNode, capture any more-precise type permanently into Node
1734 if (t != n->bottom_type()) {
1735 hash_delete(n); // changing bottom type may force a rehash
1736 n->raise_bottom_type(t);
1737 _worklist.push(n); // n re-enters the hash table via the worklist
1738 }
1740 // Idealize graph using DU info. Must clone() into new-space.
1741 // DU info is generally used to show profitability, progress or safety
1742 // (but generally not needed for correctness).
1743 Node *nn = n->Ideal_DU_postCCP(this);
1745 // TEMPORARY fix to ensure that 2nd GVN pass eliminates NULL checks
1746 switch( n->Opcode() ) {
1747 case Op_FastLock: // Revisit FastLocks for lock coarsening
1748 case Op_If:
1749 case Op_CountedLoopEnd:
1750 case Op_Region:
1751 case Op_Loop:
1752 case Op_CountedLoop:
1753 case Op_Conv2B:
1754 case Op_Opaque1:
1755 case Op_Opaque2:
1756 _worklist.push(n);
1757 break;
1758 default:
1759 break;
1760 }
1761 if( nn ) {
1762 _worklist.push(n);
1763 // Put users of 'n' onto worklist for second igvn transform
1764 add_users_to_worklist(n);
1765 return nn;
1766 }
1768 return n;
1769 }
1771 //---------------------------------saturate------------------------------------
1772 const Type* PhaseCCP::saturate(const Type* new_type, const Type* old_type,
1773 const Type* limit_type) const {
1774 const Type* wide_type = new_type->widen(old_type, limit_type);
1775 if (wide_type != new_type) { // did we widen?
1776 // If so, we may have widened beyond the limit type. Clip it back down.
1777 new_type = wide_type->filter(limit_type);
1778 }
1779 return new_type;
1780 }
1782 //------------------------------print_statistics-------------------------------
1783 #ifndef PRODUCT
1784 void PhaseCCP::print_statistics() {
1785 tty->print_cr("CCP: %d constants found: %d", _total_invokes, _total_constants);
1786 }
1787 #endif
1790 //=============================================================================
1791 #ifndef PRODUCT
1792 uint PhasePeephole::_total_peepholes = 0;
1793 #endif
1794 //------------------------------PhasePeephole----------------------------------
1795 // Conditional Constant Propagation, ala Wegman & Zadeck
1796 PhasePeephole::PhasePeephole( PhaseRegAlloc *regalloc, PhaseCFG &cfg )
1797 : PhaseTransform(Peephole), _regalloc(regalloc), _cfg(cfg) {
1798 NOT_PRODUCT( clear_peepholes(); )
1799 }
1801 #ifndef PRODUCT
1802 //------------------------------~PhasePeephole---------------------------------
1803 PhasePeephole::~PhasePeephole() {
1804 _total_peepholes += count_peepholes();
1805 }
1806 #endif
1808 //------------------------------transform--------------------------------------
1809 Node *PhasePeephole::transform( Node *n ) {
1810 ShouldNotCallThis();
1811 return NULL;
1812 }
1814 //------------------------------do_transform-----------------------------------
1815 void PhasePeephole::do_transform() {
1816 bool method_name_not_printed = true;
1818 // Examine each basic block
1819 for (uint block_number = 1; block_number < _cfg.number_of_blocks(); ++block_number) {
1820 Block* block = _cfg.get_block(block_number);
1821 bool block_not_printed = true;
1823 // and each instruction within a block
1824 uint end_index = block->number_of_nodes();
1825 // block->end_idx() not valid after PhaseRegAlloc
1826 for( uint instruction_index = 1; instruction_index < end_index; ++instruction_index ) {
1827 Node *n = block->get_node(instruction_index);
1828 if( n->is_Mach() ) {
1829 MachNode *m = n->as_Mach();
1830 int deleted_count = 0;
1831 // check for peephole opportunities
1832 MachNode *m2 = m->peephole( block, instruction_index, _regalloc, deleted_count, C );
1833 if( m2 != NULL ) {
1834 #ifndef PRODUCT
1835 if( PrintOptoPeephole ) {
1836 // Print method, first time only
1837 if( C->method() && method_name_not_printed ) {
1838 C->method()->print_short_name(); tty->cr();
1839 method_name_not_printed = false;
1840 }
1841 // Print this block
1842 if( Verbose && block_not_printed) {
1843 tty->print_cr("in block");
1844 block->dump();
1845 block_not_printed = false;
1846 }
1847 // Print instructions being deleted
1848 for( int i = (deleted_count - 1); i >= 0; --i ) {
1849 block->get_node(instruction_index-i)->as_Mach()->format(_regalloc); tty->cr();
1850 }
1851 tty->print_cr("replaced with");
1852 // Print new instruction
1853 m2->format(_regalloc);
1854 tty->print("\n\n");
1855 }
1856 #endif
1857 // Remove old nodes from basic block and update instruction_index
1858 // (old nodes still exist and may have edges pointing to them
1859 // as register allocation info is stored in the allocator using
1860 // the node index to live range mappings.)
1861 uint safe_instruction_index = (instruction_index - deleted_count);
1862 for( ; (instruction_index > safe_instruction_index); --instruction_index ) {
1863 block->remove_node( instruction_index );
1864 }
1865 // install new node after safe_instruction_index
1866 block->insert_node(m2, safe_instruction_index + 1);
1867 end_index = block->number_of_nodes() - 1; // Recompute new block size
1868 NOT_PRODUCT( inc_peepholes(); )
1869 }
1870 }
1871 }
1872 }
1873 }
1875 //------------------------------print_statistics-------------------------------
1876 #ifndef PRODUCT
1877 void PhasePeephole::print_statistics() {
1878 tty->print_cr("Peephole: peephole rules applied: %d", _total_peepholes);
1879 }
1880 #endif
1883 //=============================================================================
1884 //------------------------------set_req_X--------------------------------------
1885 void Node::set_req_X( uint i, Node *n, PhaseIterGVN *igvn ) {
1886 assert( is_not_dead(n), "can not use dead node");
1887 assert( igvn->hash_find(this) != this, "Need to remove from hash before changing edges" );
1888 Node *old = in(i);
1889 set_req(i, n);
1891 // old goes dead?
1892 if( old ) {
1893 switch (old->outcnt()) {
1894 case 0:
1895 // Put into the worklist to kill later. We do not kill it now because the
1896 // recursive kill will delete the current node (this) if dead-loop exists
1897 if (!old->is_top())
1898 igvn->_worklist.push( old );
1899 break;
1900 case 1:
1901 if( old->is_Store() || old->has_special_unique_user() )
1902 igvn->add_users_to_worklist( old );
1903 break;
1904 case 2:
1905 if( old->is_Store() )
1906 igvn->add_users_to_worklist( old );
1907 if( old->Opcode() == Op_Region )
1908 igvn->_worklist.push(old);
1909 break;
1910 case 3:
1911 if( old->Opcode() == Op_Region ) {
1912 igvn->_worklist.push(old);
1913 igvn->add_users_to_worklist( old );
1914 }
1915 break;
1916 default:
1917 break;
1918 }
1919 }
1921 }
1923 //-------------------------------replace_by-----------------------------------
1924 // Using def-use info, replace one node for another. Follow the def-use info
1925 // to all users of the OLD node. Then make all uses point to the NEW node.
1926 void Node::replace_by(Node *new_node) {
1927 assert(!is_top(), "top node has no DU info");
1928 for (DUIterator_Last imin, i = last_outs(imin); i >= imin; ) {
1929 Node* use = last_out(i);
1930 uint uses_found = 0;
1931 for (uint j = 0; j < use->len(); j++) {
1932 if (use->in(j) == this) {
1933 if (j < use->req())
1934 use->set_req(j, new_node);
1935 else use->set_prec(j, new_node);
1936 uses_found++;
1937 }
1938 }
1939 i -= uses_found; // we deleted 1 or more copies of this edge
1940 }
1941 }
1943 //=============================================================================
1944 //-----------------------------------------------------------------------------
1945 void Type_Array::grow( uint i ) {
1946 if( !_max ) {
1947 _max = 1;
1948 _types = (const Type**)_a->Amalloc( _max * sizeof(Type*) );
1949 _types[0] = NULL;
1950 }
1951 uint old = _max;
1952 while( i >= _max ) _max <<= 1; // Double to fit
1953 _types = (const Type**)_a->Arealloc( _types, old*sizeof(Type*),_max*sizeof(Type*));
1954 memset( &_types[old], 0, (_max-old)*sizeof(Type*) );
1955 }
1957 //------------------------------dump-------------------------------------------
1958 #ifndef PRODUCT
1959 void Type_Array::dump() const {
1960 uint max = Size();
1961 for( uint i = 0; i < max; i++ ) {
1962 if( _types[i] != NULL ) {
1963 tty->print(" %d\t== ", i); _types[i]->dump(); tty->cr();
1964 }
1965 }
1966 }
1967 #endif
