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 virtual PhaseIterGVN *is_IterGVN() { return 0; } 194 195 // Get a previously recorded type for the node n. 196 // This type must already have been recorded. 197 // If you want the type of a very new (untransformed) node, 198 // you must use type_or_null, and test the result for NULL. 199 const Type* type(const Node* n) const { 200 assert(n != NULL, "must not be null"); 201 const Type* t = _types.fast_lookup(n->_idx); 202 assert(t != NULL, "must set before get"); 203 return t; 204 } 205 // Get a previously recorded type for the node n, 206 // or else return NULL if there is none. 207 const Type* type_or_null(const Node* n) const { 208 return _types.fast_lookup(n->_idx); 209 } 210 // Record a type for a node. 211 void set_type(const Node* n, const Type *t) { 212 assert(t != NULL, "type must not be null"); 213 _types.map(n->_idx, t); 214 } 215 // Record an initial type for a node, the node's bottom type. 216 void set_type_bottom(const Node* n) { 217 // Use this for initialization when bottom_type() (or better) is not handy. 218 // Usually the initialization shoudl be to n->Value(this) instead, 219 // or a hand-optimized value like Type::MEMORY or Type::CONTROL. 220 assert(_types[n->_idx] == NULL, "must set the initial type just once"); 221 _types.map(n->_idx, n->bottom_type()); 222 } 223 // Make sure the types array is big enough to record a size for the node n. 224 // (In product builds, we never want to do range checks on the types array!) 225 void ensure_type_or_null(const Node* n) { 226 if (n->_idx >= _types.Size()) 227 _types.map(n->_idx, NULL); // Grow the types array as needed. 228 } 229 230 // Utility functions: 231 const TypeInt* find_int_type( Node* n); 232 const TypeLong* find_long_type(Node* n); 233 jint find_int_con( Node* n, jint value_if_unknown) { 234 const TypeInt* t = find_int_type(n); 235 return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown; 236 } 237 jlong find_long_con(Node* n, jlong value_if_unknown) { 238 const TypeLong* t = find_long_type(n); 239 return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown; 240 } 241 242 // Make an idealized constant, i.e., one of ConINode, ConPNode, ConFNode, etc. 243 // Same as transform(ConNode::make(t)). 244 ConNode* makecon(const Type* t); 245 virtual ConNode* uncached_makecon(const Type* t) // override in PhaseValues 246 { ShouldNotCallThis(); return NULL; } 247 248 // Fast int or long constant. Same as TypeInt::make(i) or TypeLong::make(l). 249 ConINode* intcon(jint i); 250 ConLNode* longcon(jlong l); 251 252 // Fast zero or null constant. Same as makecon(Type::get_zero_type(bt)). 253 ConNode* zerocon(BasicType bt); 254 255 // Return a node which computes the same function as this node, but 256 // in a faster or cheaper fashion. 257 virtual Node *transform( Node *n ) = 0; 258 259 // Return whether two Nodes are equivalent. 260 // Must not be recursive, since the recursive version is built from this. 261 // For pessimistic optimizations this is simply pointer equivalence. 262 bool eqv(const Node* n1, const Node* n2) const; 263 264 // For pessimistic passes, the return type must monotonically narrow. 265 // For optimistic passes, the return type must monotonically widen. 266 // It is possible to get into a "death march" in either type of pass, 267 // where the types are continually moving but it will take 2**31 or 268 // more steps to converge. This doesn't happen on most normal loops. 269 // 270 // Here is an example of a deadly loop for an optimistic pass, along 271 // with a partial trace of inferred types: 272 // x = phi(0,x'); L: x' = x+1; if (x' >= 0) goto L; 273 // 0 1 join([0..max], 1) 274 // [0..1] [1..2] join([0..max], [1..2]) 275 // [0..2] [1..3] join([0..max], [1..3]) 276 // ... ... ... 277 // [0..max] [min]u[1..max] join([0..max], [min..max]) 278 // [0..max] ==> fixpoint 279 // We would have proven, the hard way, that the iteration space is all 280 // non-negative ints, with the loop terminating due to 32-bit overflow. 281 // 282 // Here is the corresponding example for a pessimistic pass: 283 // x = phi(0,x'); L: x' = x-1; if (x' >= 0) goto L; 284 // int int join([0..max], int) 285 // [0..max] [-1..max-1] join([0..max], [-1..max-1]) 286 // [0..max-1] [-1..max-2] join([0..max], [-1..max-2]) 287 // ... ... ... 288 // [0..1] [-1..0] join([0..max], [-1..0]) 289 // 0 -1 join([0..max], -1) 290 // 0 == fixpoint 291 // We would have proven, the hard way, that the iteration space is {0}. 292 // (Usually, other optimizations will make the "if (x >= 0)" fold up 293 // before we get into trouble. But not always.) 294 // 295 // It's a pleasant thing to observe that the pessimistic pass 296 // will make short work of the optimistic pass's deadly loop, 297 // and vice versa. That is a good example of the complementary 298 // purposes of the CCP (optimistic) vs. GVN (pessimistic) phases. 299 // 300 // In any case, only widen or narrow a few times before going to the 301 // correct flavor of top or bottom. 302 // 303 // This call only needs to be made once as the data flows around any 304 // given cycle. We do it at Phis, and nowhere else. 305 // The types presented are the new type of a phi (computed by PhiNode::Value) 306 // and the previously computed type, last time the phi was visited. 307 // 308 // The third argument is upper limit for the saturated value, 309 // if the phase wishes to widen the new_type. 310 // If the phase is narrowing, the old type provides a lower limit. 311 // Caller guarantees that old_type and new_type are no higher than limit_type. 312 virtual const Type* saturate(const Type* new_type, const Type* old_type, 313 const Type* limit_type) const 314 { ShouldNotCallThis(); return NULL; } 315 316 // Delayed node rehash if this is an IGVN phase 317 virtual void igvn_rehash_node_delayed(Node* n) {} 318 319 #ifndef PRODUCT 320 void dump_old2new_map() const; 321 void dump_new( uint new_lidx ) const; 322 void dump_types() const; 323 void dump_nodes_and_types(const Node *root, uint depth, bool only_ctrl = true); 324 void dump_nodes_and_types_recur( const Node *n, uint depth, bool only_ctrl, VectorSet &visited); 325 326 uint _count_progress; // For profiling, count transforms that make progress 327 void set_progress() { ++_count_progress; assert( allow_progress(),"No progress allowed during verification"); } 328 void clear_progress() { _count_progress = 0; } 329 uint made_progress() const { return _count_progress; } 330 331 uint _count_transforms; // For profiling, count transforms performed 332 void set_transforms() { ++_count_transforms; } 333 void clear_transforms() { _count_transforms = 0; } 334 uint made_transforms() const{ return _count_transforms; } 335 336 bool _allow_progress; // progress not allowed during verification pass 337 void set_allow_progress(bool allow) { _allow_progress = allow; } 338 bool allow_progress() { return _allow_progress; } 339 #endif 340 }; 341 342 //------------------------------PhaseValues------------------------------------ 343 // Phase infrastructure to support values 344 class PhaseValues : public PhaseTransform { 345 protected: 346 NodeHash _table; // Hash table for value-numbering 347 348 public: 349 PhaseValues( Arena *arena, uint est_max_size ); 350 PhaseValues( PhaseValues *pt ); 351 PhaseValues( PhaseValues *ptv, const char *dummy ); 352 NOT_PRODUCT( ~PhaseValues(); ) 353 virtual PhaseIterGVN *is_IterGVN() { return 0; } 354 355 // Some Ideal and other transforms delete --> modify --> insert values 356 bool hash_delete(Node *n) { return _table.hash_delete(n); } 357 void hash_insert(Node *n) { _table.hash_insert(n); } 358 Node *hash_find_insert(Node *n){ return _table.hash_find_insert(n); } 359 Node *hash_find(const Node *n) { return _table.hash_find(n); } 360 361 // Used after parsing to eliminate values that are no longer in program 362 void remove_useless_nodes(VectorSet &useful) { 363 _table.remove_useless_nodes(useful); 364 // this may invalidate cached cons so reset the cache 365 init_con_caches(); 366 } 367 368 virtual ConNode* uncached_makecon(const Type* t); // override from PhaseTransform 369 370 virtual const Type* saturate(const Type* new_type, const Type* old_type, 371 const Type* limit_type) const 372 { return new_type; } 373 374 #ifndef PRODUCT 375 uint _count_new_values; // For profiling, count new values produced 376 void inc_new_values() { ++_count_new_values; } 377 void clear_new_values() { _count_new_values = 0; } 378 uint made_new_values() const { return _count_new_values; } 379 #endif 380 }; 381 382 383 //------------------------------PhaseGVN--------------------------------------- 384 // Phase for performing local, pessimistic GVN-style optimizations. 385 class PhaseGVN : public PhaseValues { 386 public: 387 PhaseGVN( Arena *arena, uint est_max_size ) : PhaseValues( arena, est_max_size ) {} 388 PhaseGVN( PhaseGVN *gvn ) : PhaseValues( gvn ) {} 389 PhaseGVN( PhaseGVN *gvn, const char *dummy ) : PhaseValues( gvn, dummy ) {} 390 391 // Return a node which computes the same function as this node, but 392 // in a faster or cheaper fashion. 393 Node *transform( Node *n ); 394 Node *transform_no_reclaim( Node *n ); 395 virtual void record_for_igvn(Node *n) { 396 C->record_for_igvn(n); 397 } 398 399 void replace_with(PhaseGVN* gvn) { 400 _table.replace_with(&gvn->_table); 401 _types = gvn->_types; 402 } 403 404 // Check for a simple dead loop when a data node references itself. 405 DEBUG_ONLY(void dead_loop_check(Node *n);) 406 }; 407 408 //------------------------------PhaseIterGVN----------------------------------- 409 // Phase for iteratively performing local, pessimistic GVN-style optimizations. 410 // and ideal transformations on the graph. 411 class PhaseIterGVN : public PhaseGVN { 412 private: 413 bool _delay_transform; // When true simply register the node when calling transform 414 // instead of actually optimizing it 415 416 // Idealize old Node 'n' with respect to its inputs and its value 417 virtual Node *transform_old( Node *a_node ); 418 419 // Subsume users of node 'old' into node 'nn' 420 void subsume_node( Node *old, Node *nn ); 421 422 Node_Stack _stack; // Stack used to avoid recursion 423 424 protected: 425 426 // Warm up hash table, type table and initial worklist 427 void init_worklist( Node *a_root ); 428 429 virtual const Type* saturate(const Type* new_type, const Type* old_type, 430 const Type* limit_type) const; 431 // Usually returns new_type. Returns old_type if new_type is only a slight 432 // improvement, such that it would take many (>>10) steps to reach 2**32. 433 434 public: 435 PhaseIterGVN( PhaseIterGVN *igvn ); // Used by CCP constructor 436 PhaseIterGVN( PhaseGVN *gvn ); // Used after Parser 437 PhaseIterGVN( PhaseIterGVN *igvn, const char *dummy ); // Used after +VerifyOpto 438 439 // Idealize new Node 'n' with respect to its inputs and its value 440 virtual Node *transform( Node *a_node ); 441 virtual void record_for_igvn(Node *n) { } 442 443 virtual PhaseIterGVN *is_IterGVN() { return this; } 444 445 Unique_Node_List _worklist; // Iterative worklist 446 447 // Given def-use info and an initial worklist, apply Node::Ideal, 448 // Node::Value, Node::Identity, hash-based value numbering, Node::Ideal_DU 449 // and dominator info to a fixed point. 450 void optimize(); 451 452 #ifndef PRODUCT 453 void trace_PhaseIterGVN(Node* n, Node* nn, const Type* old_type); 454 void init_verifyPhaseIterGVN(); 455 void verify_PhaseIterGVN(); 456 #endif 457 458 #ifdef ASSERT 459 void dump_infinite_loop_info(Node* n); 460 void trace_PhaseIterGVN_verbose(Node* n, int num_processed); 461 #endif 462 463 // Register a new node with the iter GVN pass without transforming it. 464 // Used when we need to restructure a Region/Phi area and all the Regions 465 // and Phis need to complete this one big transform before any other 466 // transforms can be triggered on the region. 467 // Optional 'orig' is an earlier version of this node. 468 // It is significant only for debugging and profiling. 469 Node* register_new_node_with_optimizer(Node* n, Node* orig = NULL); 470 471 // Kill a globally dead Node. All uses are also globally dead and are 472 // aggressively trimmed. 473 void remove_globally_dead_node( Node *dead ); 474 475 // Kill all inputs to a dead node, recursively making more dead nodes. 476 // The Node must be dead locally, i.e., have no uses. 477 void remove_dead_node( Node *dead ) { 478 assert(dead->outcnt() == 0 && !dead->is_top(), "node must be dead"); 479 remove_globally_dead_node(dead); 480 } 481 482 // Add users of 'n' to worklist 483 void add_users_to_worklist0( Node *n ); 484 void add_users_to_worklist ( Node *n ); 485 486 // Replace old node with new one. 487 void replace_node( Node *old, Node *nn ) { 488 add_users_to_worklist(old); 489 hash_delete(old); // Yank from hash before hacking edges 490 subsume_node(old, nn); 491 } 492 493 // Delayed node rehash: remove a node from the hash table and rehash it during 494 // next optimizing pass 495 void rehash_node_delayed(Node* n) { 496 hash_delete(n); 497 _worklist.push(n); 498 } 499 500 void igvn_rehash_node_delayed(Node* n) { 501 rehash_node_delayed(n); 502 } 503 504 // Replace ith edge of "n" with "in" 505 void replace_input_of(Node* n, int i, Node* in) { 506 rehash_node_delayed(n); 507 n->set_req(i, in); 508 } 509 510 // Delete ith edge of "n" 511 void delete_input_of(Node* n, int i) { 512 rehash_node_delayed(n); 513 n->del_req(i); 514 } 515 516 bool delay_transform() const { return _delay_transform; } 517 518 void set_delay_transform(bool delay) { 519 _delay_transform = delay; 520 } 521 522 // Clone loop predicates. Defined in loopTransform.cpp. 523 Node* clone_loop_predicates(Node* old_entry, Node* new_entry, bool clone_limit_check); 524 // Create a new if below new_entry for the predicate to be cloned 525 ProjNode* create_new_if_for_predicate(ProjNode* cont_proj, Node* new_entry, 526 Deoptimization::DeoptReason reason); 527 528 void remove_speculative_types(); 529 void check_no_speculative_types() { 530 _table.check_no_speculative_types(); 531 } 532 533 #ifndef PRODUCT 534 protected: 535 // Sub-quadratic implementation of VerifyIterativeGVN. 536 julong _verify_counter; 537 julong _verify_full_passes; 538 enum { _verify_window_size = 30 }; 539 Node* _verify_window[_verify_window_size]; 540 void verify_step(Node* n); 541 #endif 542 }; 543 544 //------------------------------PhaseCCP--------------------------------------- 545 // Phase for performing global Conditional Constant Propagation. 546 // Should be replaced with combined CCP & GVN someday. 547 class PhaseCCP : public PhaseIterGVN { 548 // Non-recursive. Use analysis to transform single Node. 549 virtual Node *transform_once( Node *n ); 550 551 public: 552 PhaseCCP( PhaseIterGVN *igvn ); // Compute conditional constants 553 NOT_PRODUCT( ~PhaseCCP(); ) 554 555 // Worklist algorithm identifies constants 556 void analyze(); 557 // Recursive traversal of program. Used analysis to modify program. 558 virtual Node *transform( Node *n ); 559 // Do any transformation after analysis 560 void do_transform(); 561 562 virtual const Type* saturate(const Type* new_type, const Type* old_type, 563 const Type* limit_type) const; 564 // Returns new_type->widen(old_type), which increments the widen bits until 565 // giving up with TypeInt::INT or TypeLong::LONG. 566 // Result is clipped to limit_type if necessary. 567 568 #ifndef PRODUCT 569 static uint _total_invokes; // For profiling, count invocations 570 void inc_invokes() { ++PhaseCCP::_total_invokes; } 571 572 static uint _total_constants; // For profiling, count constants found 573 uint _count_constants; 574 void clear_constants() { _count_constants = 0; } 575 void inc_constants() { ++_count_constants; } 576 uint count_constants() const { return _count_constants; } 577 578 static void print_statistics(); 579 #endif 580 }; 581 582 583 //------------------------------PhasePeephole---------------------------------- 584 // Phase for performing peephole optimizations on register allocated basic blocks. 585 class PhasePeephole : public PhaseTransform { 586 PhaseRegAlloc *_regalloc; 587 PhaseCFG &_cfg; 588 // Recursive traversal of program. Pure function is unused in this phase 589 virtual Node *transform( Node *n ); 590 591 public: 592 PhasePeephole( PhaseRegAlloc *regalloc, PhaseCFG &cfg ); 593 NOT_PRODUCT( ~PhasePeephole(); ) 594 595 // Do any transformation after analysis 596 void do_transform(); 597 598 #ifndef PRODUCT 599 static uint _total_peepholes; // For profiling, count peephole rules applied 600 uint _count_peepholes; 601 void clear_peepholes() { _count_peepholes = 0; } 602 void inc_peepholes() { ++_count_peepholes; } 603 uint count_peepholes() const { return _count_peepholes; } 604 605 static void print_statistics(); 606 #endif 607 }; 608 609 #endif // SHARE_VM_OPTO_PHASEX_HPP