1 /* 2 * Copyright (c) 1997, 2013, 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 #ifndef SHARE_VM_OPTO_PHASEX_HPP 26 #define SHARE_VM_OPTO_PHASEX_HPP 27 28 #include "libadt/dict.hpp" 29 #include "libadt/vectset.hpp" 30 #include "memory/resourceArea.hpp" 31 #include "opto/memnode.hpp" 32 #include "opto/node.hpp" 33 #include "opto/phase.hpp" 34 #include "opto/type.hpp" 35 36 class Compile; 37 class ConINode; 38 class ConLNode; 39 class Node; 40 class Type; 41 class PhaseTransform; 42 class PhaseGVN; 43 class PhaseIterGVN; 44 class PhaseCCP; 45 class PhasePeephole; 46 class PhaseRegAlloc; 47 48 49 //----------------------------------------------------------------------------- 50 // Expandable closed hash-table of nodes, initialized to NULL. 51 // Note that the constructor just zeros things 52 // Storage is reclaimed when the Arena's lifetime is over. 53 class NodeHash : public StackObj { 54 protected: 55 Arena *_a; // Arena to allocate in 56 uint _max; // Size of table (power of 2) 57 uint _inserts; // For grow and debug, count of hash_inserts 58 uint _insert_limit; // 'grow' when _inserts reaches _insert_limit 59 Node **_table; // Hash table of Node pointers 60 Node *_sentinel; // Replaces deleted entries in hash table 61 62 public: 63 NodeHash(uint est_max_size); 64 NodeHash(Arena *arena, uint est_max_size); 65 NodeHash(NodeHash *use_this_state); 66 #ifdef ASSERT 67 ~NodeHash(); // Unlock all nodes upon destruction of table. 68 void operator=(const NodeHash&); // Unlock all nodes upon replacement of table. 69 #endif 70 Node *hash_find(const Node*);// Find an equivalent version in hash table 71 Node *hash_find_insert(Node*);// If not in table insert else return found node 72 void hash_insert(Node*); // Insert into hash table 73 bool hash_delete(const Node*);// Replace with _sentinel in hash table 74 void check_grow() { 75 _inserts++; 76 if( _inserts == _insert_limit ) { grow(); } 77 assert( _inserts <= _insert_limit, "hash table overflow"); 78 assert( _inserts < _max, "hash table overflow" ); 79 } 80 static uint round_up(uint); // Round up to nearest power of 2 81 void grow(); // Grow _table to next power of 2 and rehash 82 // Return 75% of _max, rounded up. 83 uint insert_limit() const { return _max - (_max>>2); } 84 85 void clear(); // Set all entries to NULL, keep storage. 86 // Size of hash table 87 uint size() const { return _max; } 88 // Return Node* at index in table 89 Node *at(uint table_index) { 90 assert(table_index < _max, "Must be within table"); 91 return _table[table_index]; 92 } 93 94 void remove_useless_nodes(VectorSet &useful); // replace with sentinel 95 void replace_with(NodeHash* nh); 96 void check_no_speculative_types(); // Check no speculative part for type nodes in table 97 98 Node *sentinel() { return _sentinel; } 99 100 #ifndef PRODUCT 101 Node *find_index(uint idx); // For debugging 102 void dump(); // For debugging, dump statistics 103 uint _grows; // For debugging, count of table grow()s 104 uint _look_probes; // For debugging, count of hash probes 105 uint _lookup_hits; // For debugging, count of hash_finds 106 uint _lookup_misses; // For debugging, count of hash_finds 107 uint _insert_probes; // For debugging, count of hash probes 108 uint _delete_probes; // For debugging, count of hash probes for deletes 109 uint _delete_hits; // For debugging, count of hash probes for deletes 110 uint _delete_misses; // For debugging, count of hash probes for deletes 111 uint _total_inserts; // For debugging, total inserts into hash table 112 uint _total_insert_probes; // For debugging, total probes while inserting 113 #endif 114 }; 115 116 117 //----------------------------------------------------------------------------- 118 // Map dense integer indices to Types. Uses classic doubling-array trick. 119 // Abstractly provides an infinite array of Type*'s, initialized to NULL. 120 // Note that the constructor just zeros things, and since I use Arena 121 // allocation I do not need a destructor to reclaim storage. 122 // Despite the general name, this class is customized for use by PhaseTransform. 123 class Type_Array : public StackObj { 124 Arena *_a; // Arena to allocate in 125 uint _max; 126 const Type **_types; 127 void grow( uint i ); // Grow array node to fit 128 const Type *operator[] ( uint i ) const // Lookup, or NULL for not mapped 129 { return (i<_max) ? _types[i] : (Type*)NULL; } 130 friend class PhaseTransform; 131 public: 132 Type_Array(Arena *a) : _a(a), _max(0), _types(0) {} 133 Type_Array(Type_Array *ta) : _a(ta->_a), _max(ta->_max), _types(ta->_types) { } 134 const Type *fast_lookup(uint i) const{assert(i<_max,"oob");return _types[i];} 135 // Extend the mapping: index i maps to Type *n. 136 void map( uint i, const Type *n ) { if( i>=_max ) grow(i); _types[i] = n; } 137 uint Size() const { return _max; } 138 #ifndef PRODUCT 139 void dump() const; 140 #endif 141 }; 142 143 144 //------------------------------PhaseRemoveUseless----------------------------- 145 // Remove useless nodes from GVN hash-table, worklist, and graph 146 class PhaseRemoveUseless : public Phase { 147 protected: 148 Unique_Node_List _useful; // Nodes reachable from root 149 // list is allocated from current resource area 150 public: 151 PhaseRemoveUseless( PhaseGVN *gvn, Unique_Node_List *worklist ); 152 153 Unique_Node_List *get_useful() { return &_useful; } 154 }; 155 156 157 //------------------------------PhaseTransform--------------------------------- 158 // Phases that analyze, then transform. Constructing the Phase object does any 159 // global or slow analysis. The results are cached later for a fast 160 // transformation pass. When the Phase object is deleted the cached analysis 161 // results are deleted. 162 class PhaseTransform : public Phase { 163 protected: 164 Arena* _arena; 165 Node_Array _nodes; // Map old node indices to new nodes. 166 Type_Array _types; // Map old node indices to Types. 167 168 // ConNode caches: 169 enum { _icon_min = -1 * HeapWordSize, 170 _icon_max = 16 * HeapWordSize, 171 _lcon_min = _icon_min, 172 _lcon_max = _icon_max, 173 _zcon_max = (uint)T_CONFLICT 174 }; 175 ConINode* _icons[_icon_max - _icon_min + 1]; // cached jint constant nodes 176 ConLNode* _lcons[_lcon_max - _lcon_min + 1]; // cached jlong constant nodes 177 ConNode* _zcons[_zcon_max + 1]; // cached is_zero_type nodes 178 void init_con_caches(); 179 180 // Support both int and long caches because either might be an intptr_t, 181 // so they show up frequently in address computations. 182 183 public: 184 PhaseTransform( PhaseNumber pnum ); 185 PhaseTransform( Arena *arena, PhaseNumber pnum ); 186 PhaseTransform( PhaseTransform *phase, PhaseNumber pnum ); 187 188 Arena* arena() { return _arena; } 189 Type_Array& types() { return _types; } 190 // _nodes is used in varying ways by subclasses, which define local accessors 191 192 public: 193 // Get a previously recorded type for the node n. 194 // This type must already have been recorded. 195 // If you want the type of a very new (untransformed) node, 196 // you must use type_or_null, and test the result for NULL. 197 const Type* type(const Node* n) const { 198 assert(n != NULL, "must not be null"); 199 const Type* t = _types.fast_lookup(n->_idx); 200 assert(t != NULL, "must set before get"); 201 return t; 202 } 203 // Get a previously recorded type for the node n, 204 // or else return NULL if there is none. 205 const Type* type_or_null(const Node* n) const { 206 return _types.fast_lookup(n->_idx); 207 } 208 // Record a type for a node. 209 void set_type(const Node* n, const Type *t) { 210 assert(t != NULL, "type must not be null"); 211 _types.map(n->_idx, t); 212 } 213 // Record an initial type for a node, the node's bottom type. 214 void set_type_bottom(const Node* n) { 215 // Use this for initialization when bottom_type() (or better) is not handy. 216 // Usually the initialization shoudl be to n->Value(this) instead, 217 // or a hand-optimized value like Type::MEMORY or Type::CONTROL. 218 assert(_types[n->_idx] == NULL, "must set the initial type just once"); 219 _types.map(n->_idx, n->bottom_type()); 220 } 221 // Make sure the types array is big enough to record a size for the node n. 222 // (In product builds, we never want to do range checks on the types array!) 223 void ensure_type_or_null(const Node* n) { 224 if (n->_idx >= _types.Size()) 225 _types.map(n->_idx, NULL); // Grow the types array as needed. 226 } 227 228 // Utility functions: 229 const TypeInt* find_int_type( Node* n); 230 const TypeLong* find_long_type(Node* n); 231 jint find_int_con( Node* n, jint value_if_unknown) { 232 const TypeInt* t = find_int_type(n); 233 return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown; 234 } 235 jlong find_long_con(Node* n, jlong value_if_unknown) { 236 const TypeLong* t = find_long_type(n); 237 return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown; 238 } 239 240 // Make an idealized constant, i.e., one of ConINode, ConPNode, ConFNode, etc. 241 // Same as transform(ConNode::make(t)). 242 ConNode* makecon(const Type* t); 243 virtual ConNode* uncached_makecon(const Type* t) // override in PhaseValues 244 { ShouldNotCallThis(); return NULL; } 245 246 // Fast int or long constant. Same as TypeInt::make(i) or TypeLong::make(l). 247 ConINode* intcon(jint i); 248 ConLNode* longcon(jlong l); 249 250 // Fast zero or null constant. Same as makecon(Type::get_zero_type(bt)). 251 ConNode* zerocon(BasicType bt); 252 253 // Return a node which computes the same function as this node, but 254 // in a faster or cheaper fashion. 255 virtual Node *transform( Node *n ) = 0; 256 257 // Return whether two Nodes are equivalent. 258 // Must not be recursive, since the recursive version is built from this. 259 // For pessimistic optimizations this is simply pointer equivalence. 260 bool eqv(const Node* n1, const Node* n2) const { return n1 == n2; } 261 262 // For pessimistic passes, the return type must monotonically narrow. 263 // For optimistic passes, the return type must monotonically widen. 264 // It is possible to get into a "death march" in either type of pass, 265 // where the types are continually moving but it will take 2**31 or 266 // more steps to converge. This doesn't happen on most normal loops. 267 // 268 // Here is an example of a deadly loop for an optimistic pass, along 269 // with a partial trace of inferred types: 270 // x = phi(0,x'); L: x' = x+1; if (x' >= 0) goto L; 271 // 0 1 join([0..max], 1) 272 // [0..1] [1..2] join([0..max], [1..2]) 273 // [0..2] [1..3] join([0..max], [1..3]) 274 // ... ... ... 275 // [0..max] [min]u[1..max] join([0..max], [min..max]) 276 // [0..max] ==> fixpoint 277 // We would have proven, the hard way, that the iteration space is all 278 // non-negative ints, with the loop terminating due to 32-bit overflow. 279 // 280 // Here is the corresponding example for a pessimistic pass: 281 // x = phi(0,x'); L: x' = x-1; if (x' >= 0) goto L; 282 // int int join([0..max], int) 283 // [0..max] [-1..max-1] join([0..max], [-1..max-1]) 284 // [0..max-1] [-1..max-2] join([0..max], [-1..max-2]) 285 // ... ... ... 286 // [0..1] [-1..0] join([0..max], [-1..0]) 287 // 0 -1 join([0..max], -1) 288 // 0 == fixpoint 289 // We would have proven, the hard way, that the iteration space is {0}. 290 // (Usually, other optimizations will make the "if (x >= 0)" fold up 291 // before we get into trouble. But not always.) 292 // 293 // It's a pleasant thing to observe that the pessimistic pass 294 // will make short work of the optimistic pass's deadly loop, 295 // and vice versa. That is a good example of the complementary 296 // purposes of the CCP (optimistic) vs. GVN (pessimistic) phases. 297 // 298 // In any case, only widen or narrow a few times before going to the 299 // correct flavor of top or bottom. 300 // 301 // This call only needs to be made once as the data flows around any 302 // given cycle. We do it at Phis, and nowhere else. 303 // The types presented are the new type of a phi (computed by PhiNode::Value) 304 // and the previously computed type, last time the phi was visited. 305 // 306 // The third argument is upper limit for the saturated value, 307 // if the phase wishes to widen the new_type. 308 // If the phase is narrowing, the old type provides a lower limit. 309 // Caller guarantees that old_type and new_type are no higher than limit_type. 310 virtual const Type* saturate(const Type* new_type, const Type* old_type, 311 const Type* limit_type) const 312 { ShouldNotCallThis(); return NULL; } 313 314 // Delayed node rehash if this is an IGVN phase 315 virtual void igvn_rehash_node_delayed(Node* n) {} 316 317 #ifndef PRODUCT 318 void dump_old2new_map() const; 319 void dump_new( uint new_lidx ) const; 320 void dump_types() const; 321 void dump_nodes_and_types(const Node *root, uint depth, bool only_ctrl = true); 322 void dump_nodes_and_types_recur( const Node *n, uint depth, bool only_ctrl, VectorSet &visited); 323 324 uint _count_progress; // For profiling, count transforms that make progress 325 void set_progress() { ++_count_progress; assert( allow_progress(),"No progress allowed during verification"); } 326 void clear_progress() { _count_progress = 0; } 327 uint made_progress() const { return _count_progress; } 328 329 uint _count_transforms; // For profiling, count transforms performed 330 void set_transforms() { ++_count_transforms; } 331 void clear_transforms() { _count_transforms = 0; } 332 uint made_transforms() const{ return _count_transforms; } 333 334 bool _allow_progress; // progress not allowed during verification pass 335 void set_allow_progress(bool allow) { _allow_progress = allow; } 336 bool allow_progress() { return _allow_progress; } 337 #endif 338 }; 339 340 //------------------------------PhaseValues------------------------------------ 341 // Phase infrastructure to support values 342 class PhaseValues : public PhaseTransform { 343 protected: 344 NodeHash _table; // Hash table for value-numbering 345 346 public: 347 PhaseValues( Arena *arena, uint est_max_size ); 348 PhaseValues( PhaseValues *pt ); 349 PhaseValues( PhaseValues *ptv, const char *dummy ); 350 NOT_PRODUCT( ~PhaseValues(); ) 351 virtual PhaseIterGVN *is_IterGVN() { return 0; } 352 353 // Some Ideal and other transforms delete --> modify --> insert values 354 bool hash_delete(Node *n) { return _table.hash_delete(n); } 355 void hash_insert(Node *n) { _table.hash_insert(n); } 356 Node *hash_find_insert(Node *n){ return _table.hash_find_insert(n); } 357 Node *hash_find(const Node *n) { return _table.hash_find(n); } 358 359 // Used after parsing to eliminate values that are no longer in program 360 void remove_useless_nodes(VectorSet &useful) { 361 _table.remove_useless_nodes(useful); 362 // this may invalidate cached cons so reset the cache 363 init_con_caches(); 364 } 365 366 virtual ConNode* uncached_makecon(const Type* t); // override from PhaseTransform 367 368 virtual const Type* saturate(const Type* new_type, const Type* old_type, 369 const Type* limit_type) const 370 { return new_type; } 371 372 #ifndef PRODUCT 373 uint _count_new_values; // For profiling, count new values produced 374 void inc_new_values() { ++_count_new_values; } 375 void clear_new_values() { _count_new_values = 0; } 376 uint made_new_values() const { return _count_new_values; } 377 #endif 378 }; 379 380 381 //------------------------------PhaseGVN--------------------------------------- 382 // Phase for performing local, pessimistic GVN-style optimizations. 383 class PhaseGVN : public PhaseValues { 384 public: 385 PhaseGVN( Arena *arena, uint est_max_size ) : PhaseValues( arena, est_max_size ) {} 386 PhaseGVN( PhaseGVN *gvn ) : PhaseValues( gvn ) {} 387 PhaseGVN( PhaseGVN *gvn, const char *dummy ) : PhaseValues( gvn, dummy ) {} 388 389 // Return a node which computes the same function as this node, but 390 // in a faster or cheaper fashion. 391 Node *transform( Node *n ); 392 Node *transform_no_reclaim( Node *n ); 393 virtual void record_for_igvn(Node *n) { 394 C->record_for_igvn(n); 395 } 396 397 void replace_with(PhaseGVN* gvn) { 398 _table.replace_with(&gvn->_table); 399 _types = gvn->_types; 400 } 401 402 // Check for a simple dead loop when a data node references itself. 403 DEBUG_ONLY(void dead_loop_check(Node *n);) 404 }; 405 406 //------------------------------PhaseIterGVN----------------------------------- 407 // Phase for iteratively performing local, pessimistic GVN-style optimizations. 408 // and ideal transformations on the graph. 409 class PhaseIterGVN : public PhaseGVN { 410 private: 411 bool _delay_transform; // When true simply register the node when calling transform 412 // instead of actually optimizing it 413 414 // Idealize old Node 'n' with respect to its inputs and its value 415 virtual Node *transform_old( Node *a_node ); 416 417 // Subsume users of node 'old' into node 'nn' 418 void subsume_node( Node *old, Node *nn ); 419 420 Node_Stack _stack; // Stack used to avoid recursion 421 422 protected: 423 424 // Warm up hash table, type table and initial worklist 425 void init_worklist( Node *a_root ); 426 427 virtual const Type* saturate(const Type* new_type, const Type* old_type, 428 const Type* limit_type) const; 429 // Usually returns new_type. Returns old_type if new_type is only a slight 430 // improvement, such that it would take many (>>10) steps to reach 2**32. 431 432 public: 433 PhaseIterGVN( PhaseIterGVN *igvn ); // Used by CCP constructor 434 PhaseIterGVN( PhaseGVN *gvn ); // Used after Parser 435 PhaseIterGVN( PhaseIterGVN *igvn, const char *dummy ); // Used after +VerifyOpto 436 437 // Idealize new Node 'n' with respect to its inputs and its value 438 virtual Node *transform( Node *a_node ); 439 virtual void record_for_igvn(Node *n) { } 440 441 virtual PhaseIterGVN *is_IterGVN() { return this; } 442 443 Unique_Node_List _worklist; // Iterative worklist 444 445 // Given def-use info and an initial worklist, apply Node::Ideal, 446 // Node::Value, Node::Identity, hash-based value numbering, Node::Ideal_DU 447 // and dominator info to a fixed point. 448 void optimize(); 449 450 #ifndef PRODUCT 451 void trace_PhaseIterGVN(Node* n, Node* nn, const Type* old_type); 452 void init_verifyPhaseIterGVN(); 453 void verify_PhaseIterGVN(); 454 #endif 455 456 #ifdef ASSERT 457 void dump_infinite_loop_info(Node* n); 458 void trace_PhaseIterGVN_verbose(Node* n, int num_processed); 459 #endif 460 461 // Register a new node with the iter GVN pass without transforming it. 462 // Used when we need to restructure a Region/Phi area and all the Regions 463 // and Phis need to complete this one big transform before any other 464 // transforms can be triggered on the region. 465 // Optional 'orig' is an earlier version of this node. 466 // It is significant only for debugging and profiling. 467 Node* register_new_node_with_optimizer(Node* n, Node* orig = NULL); 468 469 // Kill a globally dead Node. All uses are also globally dead and are 470 // aggressively trimmed. 471 void remove_globally_dead_node( Node *dead ); 472 473 // Kill all inputs to a dead node, recursively making more dead nodes. 474 // The Node must be dead locally, i.e., have no uses. 475 void remove_dead_node( Node *dead ) { 476 assert(dead->outcnt() == 0 && !dead->is_top(), "node must be dead"); 477 remove_globally_dead_node(dead); 478 } 479 480 // Add users of 'n' to worklist 481 void add_users_to_worklist0( Node *n ); 482 void add_users_to_worklist ( Node *n ); 483 484 // Replace old node with new one. 485 void replace_node( Node *old, Node *nn ) { 486 add_users_to_worklist(old); 487 hash_delete(old); // Yank from hash before hacking edges 488 subsume_node(old, nn); 489 } 490 491 // Delayed node rehash: remove a node from the hash table and rehash it during 492 // next optimizing pass 493 void rehash_node_delayed(Node* n) { 494 hash_delete(n); 495 _worklist.push(n); 496 } 497 498 void igvn_rehash_node_delayed(Node* n) { 499 rehash_node_delayed(n); 500 } 501 502 // Replace ith edge of "n" with "in" 503 void replace_input_of(Node* n, int i, Node* in) { 504 rehash_node_delayed(n); 505 n->set_req(i, in); 506 } 507 508 // Delete ith edge of "n" 509 void delete_input_of(Node* n, int i) { 510 rehash_node_delayed(n); 511 n->del_req(i); 512 } 513 514 bool delay_transform() const { return _delay_transform; } 515 516 void set_delay_transform(bool delay) { 517 _delay_transform = delay; 518 } 519 520 // Clone loop predicates. Defined in loopTransform.cpp. 521 Node* clone_loop_predicates(Node* old_entry, Node* new_entry, bool clone_limit_check); 522 // Create a new if below new_entry for the predicate to be cloned 523 ProjNode* create_new_if_for_predicate(ProjNode* cont_proj, Node* new_entry, 524 Deoptimization::DeoptReason reason); 525 526 void remove_speculative_types(); 527 void check_no_speculative_types() { 528 _table.check_no_speculative_types(); 529 } 530 531 #ifndef PRODUCT 532 protected: 533 // Sub-quadratic implementation of VerifyIterativeGVN. 534 julong _verify_counter; 535 julong _verify_full_passes; 536 enum { _verify_window_size = 30 }; 537 Node* _verify_window[_verify_window_size]; 538 void verify_step(Node* n); 539 #endif 540 }; 541 542 //------------------------------PhaseCCP--------------------------------------- 543 // Phase for performing global Conditional Constant Propagation. 544 // Should be replaced with combined CCP & GVN someday. 545 class PhaseCCP : public PhaseIterGVN { 546 // Non-recursive. Use analysis to transform single Node. 547 virtual Node *transform_once( Node *n ); 548 549 public: 550 PhaseCCP( PhaseIterGVN *igvn ); // Compute conditional constants 551 NOT_PRODUCT( ~PhaseCCP(); ) 552 553 // Worklist algorithm identifies constants 554 void analyze(); 555 // Recursive traversal of program. Used analysis to modify program. 556 virtual Node *transform( Node *n ); 557 // Do any transformation after analysis 558 void do_transform(); 559 560 virtual const Type* saturate(const Type* new_type, const Type* old_type, 561 const Type* limit_type) const; 562 // Returns new_type->widen(old_type), which increments the widen bits until 563 // giving up with TypeInt::INT or TypeLong::LONG. 564 // Result is clipped to limit_type if necessary. 565 566 #ifndef PRODUCT 567 static uint _total_invokes; // For profiling, count invocations 568 void inc_invokes() { ++PhaseCCP::_total_invokes; } 569 570 static uint _total_constants; // For profiling, count constants found 571 uint _count_constants; 572 void clear_constants() { _count_constants = 0; } 573 void inc_constants() { ++_count_constants; } 574 uint count_constants() const { return _count_constants; } 575 576 static void print_statistics(); 577 #endif 578 }; 579 580 581 //------------------------------PhasePeephole---------------------------------- 582 // Phase for performing peephole optimizations on register allocated basic blocks. 583 class PhasePeephole : public PhaseTransform { 584 PhaseRegAlloc *_regalloc; 585 PhaseCFG &_cfg; 586 // Recursive traversal of program. Pure function is unused in this phase 587 virtual Node *transform( Node *n ); 588 589 public: 590 PhasePeephole( PhaseRegAlloc *regalloc, PhaseCFG &cfg ); 591 NOT_PRODUCT( ~PhasePeephole(); ) 592 593 // Do any transformation after analysis 594 void do_transform(); 595 596 #ifndef PRODUCT 597 static uint _total_peepholes; // For profiling, count peephole rules applied 598 uint _count_peepholes; 599 void clear_peepholes() { _count_peepholes = 0; } 600 void inc_peepholes() { ++_count_peepholes; } 601 uint count_peepholes() const { return _count_peepholes; } 602 603 static void print_statistics(); 604 #endif 605 }; 606 607 #endif // SHARE_VM_OPTO_PHASEX_HPP