1 /* 2 * Copyright (c) 1997, 2023, 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_OPTO_PHASEX_HPP 26 #define SHARE_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 #include "utilities/globalDefinitions.hpp" 36 37 class BarrierSetC2; 38 class Compile; 39 class ConINode; 40 class ConLNode; 41 class Node; 42 class Type; 43 class PhaseTransform; 44 class PhaseGVN; 45 class PhaseIterGVN; 46 class PhaseCCP; 47 class PhasePeephole; 48 class PhaseRegAlloc; 49 50 51 //----------------------------------------------------------------------------- 52 // Expandable closed hash-table of nodes, initialized to null. 53 // Note that the constructor just zeros things 54 // Storage is reclaimed when the Arena's lifetime is over. 55 class NodeHash : public AnyObj { 56 protected: 57 Arena *_a; // Arena to allocate in 58 uint _max; // Size of table (power of 2) 59 uint _inserts; // For grow and debug, count of hash_inserts 60 uint _insert_limit; // 'grow' when _inserts reaches _insert_limit 61 Node **_table; // Hash table of Node pointers 62 Node *_sentinel; // Replaces deleted entries in hash table 63 64 public: 65 NodeHash(Arena *arena, uint est_max_size); 66 #ifdef ASSERT 67 ~NodeHash(); // Unlock all nodes upon destruction of table. 68 #endif 69 Node *hash_find(const Node*);// Find an equivalent version in hash table 70 Node *hash_find_insert(Node*);// If not in table insert else return found node 71 void hash_insert(Node*); // Insert into hash table 72 bool hash_delete(const Node*);// Replace with _sentinel in hash table 73 void check_grow() { 74 _inserts++; 75 if( _inserts == _insert_limit ) { grow(); } 76 assert( _inserts <= _insert_limit, "hash table overflow"); 77 assert( _inserts < _max, "hash table overflow" ); 78 } 79 static uint round_up(uint); // Round up to nearest power of 2 80 void grow(); // Grow _table to next power of 2 and rehash 81 // Return 75% of _max, rounded up. 82 uint insert_limit() const { return _max - (_max>>2); } 83 84 void clear(); // Set all entries to null, keep storage. 85 // Size of hash table 86 uint size() const { return _max; } 87 // Return Node* at index in table 88 Node *at(uint table_index) { 89 assert(table_index < _max, "Must be within table"); 90 return _table[table_index]; 91 } 92 93 void remove_useless_nodes(VectorSet& useful); // replace with sentinel 94 void check_no_speculative_types(); // Check no speculative part for type nodes in table 95 96 Node *sentinel() { return _sentinel; } 97 98 #ifndef PRODUCT 99 Node *find_index(uint idx); // For debugging 100 void dump(); // For debugging, dump statistics 101 uint _grows; // For debugging, count of table grow()s 102 uint _look_probes; // For debugging, count of hash probes 103 uint _lookup_hits; // For debugging, count of hash_finds 104 uint _lookup_misses; // For debugging, count of hash_finds 105 uint _insert_probes; // For debugging, count of hash probes 106 uint _delete_probes; // For debugging, count of hash probes for deletes 107 uint _delete_hits; // For debugging, count of hash probes for deletes 108 uint _delete_misses; // For debugging, count of hash probes for deletes 109 uint _total_inserts; // For debugging, total inserts into hash table 110 uint _total_insert_probes; // For debugging, total probes while inserting 111 #endif 112 NONCOPYABLE(NodeHash); 113 }; 114 115 116 //----------------------------------------------------------------------------- 117 // Map dense integer indices to Types. Uses classic doubling-array trick. 118 // Abstractly provides an infinite array of Type*'s, initialized to null. 119 // Note that the constructor just zeros things, and since I use Arena 120 // allocation I do not need a destructor to reclaim storage. 121 // Despite the general name, this class is customized for use by PhaseValues. 122 class Type_Array : public AnyObj { 123 Arena *_a; // Arena to allocate in 124 uint _max; 125 const Type **_types; 126 void grow( uint i ); // Grow array node to fit 127 public: 128 Type_Array(Arena *a) : _a(a), _max(0), _types(0) {} 129 const Type *operator[] ( uint i ) const // Lookup, or null for not mapped 130 { return (i<_max) ? _types[i] : (Type*)nullptr; } 131 const Type *fast_lookup(uint i) const{assert(i<_max,"oob");return _types[i];} 132 // Extend the mapping: index i maps to Type *n. 133 void map( uint i, const Type *n ) { if( i>=_max ) grow(i); _types[i] = n; } 134 uint Size() const { return _max; } 135 #ifndef PRODUCT 136 void dump() const; 137 #endif 138 void swap(Type_Array &other) { 139 if (this != &other) { 140 assert(_a == other._a, "swapping for differing arenas is probably a bad idea"); 141 ::swap(_max, other._max); 142 ::swap(_types, other._types); 143 } 144 } 145 NONCOPYABLE(Type_Array); 146 }; 147 148 149 //------------------------------PhaseRemoveUseless----------------------------- 150 // Remove useless nodes from GVN hash-table, worklist, and graph 151 class PhaseRemoveUseless : public Phase { 152 protected: 153 Unique_Node_List _useful; // Nodes reachable from root 154 // list is allocated from current resource area 155 public: 156 PhaseRemoveUseless(PhaseGVN* gvn, Unique_Node_List& worklist, PhaseNumber phase_num = Remove_Useless); 157 158 Unique_Node_List *get_useful() { return &_useful; } 159 }; 160 161 //------------------------------PhaseRenumber---------------------------------- 162 // Phase that first performs a PhaseRemoveUseless, then it renumbers compiler 163 // structures accordingly. 164 class PhaseRenumberLive : public PhaseRemoveUseless { 165 protected: 166 Type_Array _new_type_array; // Storage for the updated type information. 167 GrowableArray<int> _old2new_map; 168 Node_List _delayed; 169 bool _is_pass_finished; 170 uint _live_node_count; 171 172 int update_embedded_ids(Node* n); 173 int new_index(int old_idx); 174 175 public: 176 PhaseRenumberLive(PhaseGVN* gvn, 177 Unique_Node_List& worklist, 178 PhaseNumber phase_num = Remove_Useless_And_Renumber_Live); 179 }; 180 181 182 //------------------------------PhaseTransform--------------------------------- 183 // Phases that analyze, then transform. Constructing the Phase object does any 184 // global or slow analysis. The results are cached later for a fast 185 // transformation pass. When the Phase object is deleted the cached analysis 186 // results are deleted. 187 class PhaseTransform : public Phase { 188 public: 189 PhaseTransform(PhaseNumber pnum) : Phase(pnum) { 190 #ifndef PRODUCT 191 clear_progress(); 192 clear_transforms(); 193 set_allow_progress(true); 194 #endif 195 } 196 197 // Return a node which computes the same function as this node, but 198 // in a faster or cheaper fashion. 199 virtual Node *transform( Node *n ) = 0; 200 201 // true if CFG node d dominates CFG node n 202 virtual bool is_dominator(Node *d, Node *n) { fatal("unimplemented for this pass"); return false; }; 203 204 #ifndef PRODUCT 205 uint _count_progress; // For profiling, count transforms that make progress 206 void set_progress() { ++_count_progress; assert( allow_progress(),"No progress allowed during verification"); } 207 void clear_progress() { _count_progress = 0; } 208 uint made_progress() const { return _count_progress; } 209 210 uint _count_transforms; // For profiling, count transforms performed 211 void set_transforms() { ++_count_transforms; } 212 void clear_transforms() { _count_transforms = 0; } 213 uint made_transforms() const{ return _count_transforms; } 214 215 bool _allow_progress; // progress not allowed during verification pass 216 void set_allow_progress(bool allow) { _allow_progress = allow; } 217 bool allow_progress() { return _allow_progress; } 218 #endif 219 }; 220 221 // Phase infrastructure required for Node::Value computations. 222 // 1) Type array, and accessor methods. 223 // 2) Constants cache, which requires access to the types. 224 // 3) NodeHash table, to find identical nodes (and remove/update the hash of a node on modification). 225 class PhaseValues : public PhaseTransform { 226 protected: 227 bool _iterGVN; 228 229 // Hash table for value-numbering. Reference to "C->node_hash()", 230 NodeHash &_table; 231 232 // Type array mapping node idx to Type*. Reference to "C->types()". 233 Type_Array &_types; 234 235 // ConNode caches: 236 // Support both int and long caches because either might be an intptr_t, 237 // so they show up frequently in address computations. 238 enum { _icon_min = -1 * HeapWordSize, 239 _icon_max = 16 * HeapWordSize, 240 _lcon_min = _icon_min, 241 _lcon_max = _icon_max, 242 _zcon_max = (uint)T_CONFLICT 243 }; 244 ConINode* _icons[_icon_max - _icon_min + 1]; // cached jint constant nodes 245 ConLNode* _lcons[_lcon_max - _lcon_min + 1]; // cached jlong constant nodes 246 ConNode* _zcons[_zcon_max + 1]; // cached is_zero_type nodes 247 void init_con_caches(); 248 249 public: 250 PhaseValues() : PhaseTransform(GVN), _iterGVN(false), 251 _table(*C->node_hash()), _types(*C->types()) 252 { 253 NOT_PRODUCT( clear_new_values(); ) 254 // Force allocation for currently existing nodes 255 _types.map(C->unique(), nullptr); 256 init_con_caches(); 257 } 258 NOT_PRODUCT(~PhaseValues();) 259 PhaseIterGVN* is_IterGVN() { return (_iterGVN) ? (PhaseIterGVN*)this : nullptr; } 260 261 // Some Ideal and other transforms delete --> modify --> insert values 262 bool hash_delete(Node* n) { return _table.hash_delete(n); } 263 void hash_insert(Node* n) { _table.hash_insert(n); } 264 Node* hash_find_insert(Node* n){ return _table.hash_find_insert(n); } 265 Node* hash_find(const Node* n) { return _table.hash_find(n); } 266 267 // Used after parsing to eliminate values that are no longer in program 268 void remove_useless_nodes(VectorSet &useful) { 269 _table.remove_useless_nodes(useful); 270 // this may invalidate cached cons so reset the cache 271 init_con_caches(); 272 } 273 274 Type_Array& types() { 275 return _types; 276 } 277 278 // Get a previously recorded type for the node n. 279 // This type must already have been recorded. 280 // If you want the type of a very new (untransformed) node, 281 // you must use type_or_null, and test the result for null. 282 const Type* type(const Node* n) const { 283 assert(n != nullptr, "must not be null"); 284 const Type* t = _types.fast_lookup(n->_idx); 285 assert(t != nullptr, "must set before get"); 286 return t; 287 } 288 // Get a previously recorded type for the node n, 289 // or else return null if there is none. 290 const Type* type_or_null(const Node* n) const { 291 return _types.fast_lookup(n->_idx); 292 } 293 // Record a type for a node. 294 void set_type(const Node* n, const Type *t) { 295 assert(t != nullptr, "type must not be null"); 296 _types.map(n->_idx, t); 297 } 298 void clear_type(const Node* n) { 299 if (n->_idx < _types.Size()) { 300 _types.map(n->_idx, nullptr); 301 } 302 } 303 // Record an initial type for a node, the node's bottom type. 304 void set_type_bottom(const Node* n) { 305 // Use this for initialization when bottom_type() (or better) is not handy. 306 // Usually the initialization should be to n->Value(this) instead, 307 // or a hand-optimized value like Type::MEMORY or Type::CONTROL. 308 assert(_types[n->_idx] == nullptr, "must set the initial type just once"); 309 _types.map(n->_idx, n->bottom_type()); 310 } 311 // Make sure the types array is big enough to record a size for the node n. 312 // (In product builds, we never want to do range checks on the types array!) 313 void ensure_type_or_null(const Node* n) { 314 if (n->_idx >= _types.Size()) 315 _types.map(n->_idx, nullptr); // Grow the types array as needed. 316 } 317 318 // Utility functions: 319 const TypeInt* find_int_type( Node* n); 320 const TypeLong* find_long_type(Node* n); 321 jint find_int_con( Node* n, jint value_if_unknown) { 322 const TypeInt* t = find_int_type(n); 323 return (t != nullptr && t->is_con()) ? t->get_con() : value_if_unknown; 324 } 325 jlong find_long_con(Node* n, jlong value_if_unknown) { 326 const TypeLong* t = find_long_type(n); 327 return (t != nullptr && t->is_con()) ? t->get_con() : value_if_unknown; 328 } 329 330 // Make an idealized constant, i.e., one of ConINode, ConPNode, ConFNode, etc. 331 // Same as transform(ConNode::make(t)). 332 ConNode* makecon(const Type* t); 333 ConNode* uncached_makecon(const Type* t); 334 335 // Fast int or long constant. Same as TypeInt::make(i) or TypeLong::make(l). 336 ConINode* intcon(jint i); 337 ConLNode* longcon(jlong l); 338 ConNode* integercon(jlong l, BasicType bt); 339 340 // Fast zero or null constant. Same as makecon(Type::get_zero_type(bt)). 341 ConNode* zerocon(BasicType bt); 342 343 // For pessimistic passes, the return type must monotonically narrow. 344 // For optimistic passes, the return type must monotonically widen. 345 // It is possible to get into a "death march" in either type of pass, 346 // where the types are continually moving but it will take 2**31 or 347 // more steps to converge. This doesn't happen on most normal loops. 348 // 349 // Here is an example of a deadly loop for an optimistic pass, along 350 // with a partial trace of inferred types: 351 // x = phi(0,x'); L: x' = x+1; if (x' >= 0) goto L; 352 // 0 1 join([0..max], 1) 353 // [0..1] [1..2] join([0..max], [1..2]) 354 // [0..2] [1..3] join([0..max], [1..3]) 355 // ... ... ... 356 // [0..max] [min]u[1..max] join([0..max], [min..max]) 357 // [0..max] ==> fixpoint 358 // We would have proven, the hard way, that the iteration space is all 359 // non-negative ints, with the loop terminating due to 32-bit overflow. 360 // 361 // Here is the corresponding example for a pessimistic pass: 362 // x = phi(0,x'); L: x' = x-1; if (x' >= 0) goto L; 363 // int int join([0..max], int) 364 // [0..max] [-1..max-1] join([0..max], [-1..max-1]) 365 // [0..max-1] [-1..max-2] join([0..max], [-1..max-2]) 366 // ... ... ... 367 // [0..1] [-1..0] join([0..max], [-1..0]) 368 // 0 -1 join([0..max], -1) 369 // 0 == fixpoint 370 // We would have proven, the hard way, that the iteration space is {0}. 371 // (Usually, other optimizations will make the "if (x >= 0)" fold up 372 // before we get into trouble. But not always.) 373 // 374 // It's a pleasant thing to observe that the pessimistic pass 375 // will make short work of the optimistic pass's deadly loop, 376 // and vice versa. That is a good example of the complementary 377 // purposes of the CCP (optimistic) vs. GVN (pessimistic) phases. 378 // 379 // In any case, only widen or narrow a few times before going to the 380 // correct flavor of top or bottom. 381 // 382 // This call only needs to be made once as the data flows around any 383 // given cycle. We do it at Phis, and nowhere else. 384 // The types presented are the new type of a phi (computed by PhiNode::Value) 385 // and the previously computed type, last time the phi was visited. 386 // 387 // The third argument is upper limit for the saturated value, 388 // if the phase wishes to widen the new_type. 389 // If the phase is narrowing, the old type provides a lower limit. 390 // Caller guarantees that old_type and new_type are no higher than limit_type. 391 virtual const Type* saturate(const Type* new_type, 392 const Type* old_type, 393 const Type* limit_type) const { 394 return new_type; 395 } 396 virtual const Type* saturate_and_maybe_push_to_igvn_worklist(const TypeNode* n, const Type* new_type) { 397 return saturate(new_type, type_or_null(n), n->type()); 398 } 399 400 #ifndef PRODUCT 401 uint _count_new_values; // For profiling, count new values produced 402 void inc_new_values() { ++_count_new_values; } 403 void clear_new_values() { _count_new_values = 0; } 404 uint made_new_values() const { return _count_new_values; } 405 #endif 406 }; 407 408 409 //------------------------------PhaseGVN--------------------------------------- 410 // Phase for performing local, pessimistic GVN-style optimizations. 411 class PhaseGVN : public PhaseValues { 412 protected: 413 bool is_dominator_helper(Node *d, Node *n, bool linear_only); 414 415 public: 416 // Return a node which computes the same function as this node, but 417 // in a faster or cheaper fashion. 418 Node* transform(Node* n); 419 420 virtual void record_for_igvn(Node *n) { 421 C->record_for_igvn(n); 422 } 423 424 bool is_dominator(Node *d, Node *n) { return is_dominator_helper(d, n, true); } 425 426 // Helper to call Node::Ideal() and BarrierSetC2::ideal_node(). 427 Node* apply_ideal(Node* i, bool can_reshape); 428 429 #ifdef ASSERT 430 void dump_infinite_loop_info(Node* n, const char* where); 431 // Check for a simple dead loop when a data node references itself. 432 void dead_loop_check(Node *n); 433 #endif 434 }; 435 436 //------------------------------PhaseIterGVN----------------------------------- 437 // Phase for iteratively performing local, pessimistic GVN-style optimizations. 438 // and ideal transformations on the graph. 439 class PhaseIterGVN : public PhaseGVN { 440 private: 441 bool _delay_transform; // When true simply register the node when calling transform 442 // instead of actually optimizing it 443 444 // Idealize old Node 'n' with respect to its inputs and its value 445 virtual Node *transform_old( Node *a_node ); 446 447 // Subsume users of node 'old' into node 'nn' 448 void subsume_node( Node *old, Node *nn ); 449 450 protected: 451 // Shuffle worklist, for stress testing 452 void shuffle_worklist(); 453 454 virtual const Type* saturate(const Type* new_type, const Type* old_type, 455 const Type* limit_type) const; 456 // Usually returns new_type. Returns old_type if new_type is only a slight 457 // improvement, such that it would take many (>>10) steps to reach 2**32. 458 459 public: 460 461 PhaseIterGVN(PhaseIterGVN* igvn); // Used by CCP constructor 462 PhaseIterGVN(PhaseGVN* gvn); // Used after Parser 463 464 // Reset IGVN from GVN: call deconstructor, and placement new. 465 // Achieves the same as the following (but without move constructors): 466 // igvn = PhaseIterGVN(gvn); 467 void reset_from_gvn(PhaseGVN* gvn) { 468 if (this != gvn) { 469 this->~PhaseIterGVN(); 470 ::new (static_cast<void*>(this)) PhaseIterGVN(gvn); 471 } 472 } 473 474 // Reset IGVN with another: call deconstructor, and placement new. 475 // Achieves the same as the following (but without move constructors): 476 // igvn = PhaseIterGVN(other); 477 void reset_from_igvn(PhaseIterGVN* other) { 478 if (this != other) { 479 this->~PhaseIterGVN(); 480 ::new (static_cast<void*>(this)) PhaseIterGVN(other); 481 } 482 } 483 484 // Idealize new Node 'n' with respect to its inputs and its value 485 virtual Node *transform( Node *a_node ); 486 virtual void record_for_igvn(Node *n) { _worklist.push(n); } 487 488 // Iterative worklist. Reference to "C->igvn_worklist()". 489 Unique_Node_List &_worklist; 490 491 // Given def-use info and an initial worklist, apply Node::Ideal, 492 // Node::Value, Node::Identity, hash-based value numbering, Node::Ideal_DU 493 // and dominator info to a fixed point. 494 void optimize(); 495 #ifdef ASSERT 496 void verify_optimize(); 497 bool verify_node_value(Node* n); 498 #endif 499 500 #ifndef PRODUCT 501 void trace_PhaseIterGVN(Node* n, Node* nn, const Type* old_type); 502 void init_verifyPhaseIterGVN(); 503 void verify_PhaseIterGVN(); 504 #endif 505 506 #ifdef ASSERT 507 void dump_infinite_loop_info(Node* n, const char* where); 508 void trace_PhaseIterGVN_verbose(Node* n, int num_processed); 509 #endif 510 511 // Register a new node with the iter GVN pass without transforming it. 512 // Used when we need to restructure a Region/Phi area and all the Regions 513 // and Phis need to complete this one big transform before any other 514 // transforms can be triggered on the region. 515 // Optional 'orig' is an earlier version of this node. 516 // It is significant only for debugging and profiling. 517 Node* register_new_node_with_optimizer(Node* n, Node* orig = nullptr); 518 519 // Kill a globally dead Node. All uses are also globally dead and are 520 // aggressively trimmed. 521 void remove_globally_dead_node( Node *dead ); 522 523 // Kill all inputs to a dead node, recursively making more dead nodes. 524 // The Node must be dead locally, i.e., have no uses. 525 void remove_dead_node( Node *dead ) { 526 assert(dead->outcnt() == 0 && !dead->is_top(), "node must be dead"); 527 remove_globally_dead_node(dead); 528 } 529 530 // Add users of 'n' to worklist 531 static void add_users_to_worklist0(Node* n, Unique_Node_List& worklist); 532 static void add_users_of_use_to_worklist(Node* n, Node* use, Unique_Node_List& worklist); 533 void add_users_to_worklist(Node* n); 534 535 // Replace old node with new one. 536 void replace_node( Node *old, Node *nn ) { 537 add_users_to_worklist(old); 538 hash_delete(old); // Yank from hash before hacking edges 539 subsume_node(old, nn); 540 } 541 542 void replace_in_uses(Node* n, Node* m); 543 544 // Delayed node rehash: remove a node from the hash table and rehash it during 545 // next optimizing pass 546 void rehash_node_delayed(Node* n) { 547 hash_delete(n); 548 _worklist.push(n); 549 } 550 551 // Replace ith edge of "n" with "in" 552 void replace_input_of(Node* n, uint i, Node* in) { 553 rehash_node_delayed(n); 554 n->set_req_X(i, in, this); 555 } 556 557 // Add "in" as input (req) of "n" 558 void add_input_to(Node* n, Node* in) { 559 rehash_node_delayed(n); 560 n->add_req(in); 561 } 562 563 // Delete ith edge of "n" 564 void delete_input_of(Node* n, uint i) { 565 rehash_node_delayed(n); 566 n->del_req(i); 567 } 568 569 // Delete precedence edge i of "n" 570 void delete_precedence_of(Node* n, uint i) { 571 rehash_node_delayed(n); 572 n->rm_prec(i); 573 } 574 575 bool delay_transform() const { return _delay_transform; } 576 577 void set_delay_transform(bool delay) { 578 _delay_transform = delay; 579 } 580 581 void remove_speculative_types(); 582 void check_no_speculative_types() { 583 _table.check_no_speculative_types(); 584 } 585 586 bool is_dominator(Node *d, Node *n) { return is_dominator_helper(d, n, false); } 587 bool no_dependent_zero_check(Node* n) const; 588 589 #ifndef PRODUCT 590 static bool is_verify_def_use() { 591 // '-XX:VerifyIterativeGVN=1' 592 return (VerifyIterativeGVN % 10) == 1; 593 } 594 static bool is_verify_Value() { 595 // '-XX:VerifyIterativeGVN=10' 596 return ((VerifyIterativeGVN % 100) / 10) == 1; 597 } 598 protected: 599 // Sub-quadratic implementation of '-XX:VerifyIterativeGVN=1' (Use-Def verification). 600 julong _verify_counter; 601 julong _verify_full_passes; 602 enum { _verify_window_size = 30 }; 603 Node* _verify_window[_verify_window_size]; 604 void verify_step(Node* n); 605 #endif 606 }; 607 608 //------------------------------PhaseCCP--------------------------------------- 609 // Phase for performing global Conditional Constant Propagation. 610 // Should be replaced with combined CCP & GVN someday. 611 class PhaseCCP : public PhaseIterGVN { 612 Unique_Node_List _root_and_safepoints; 613 // Non-recursive. Use analysis to transform single Node. 614 virtual Node* transform_once(Node* n); 615 616 Node* fetch_next_node(Unique_Node_List& worklist); 617 static void dump_type_and_node(const Node* n, const Type* t) PRODUCT_RETURN; 618 619 void push_child_nodes_to_worklist(Unique_Node_List& worklist, Node* n) const; 620 void push_if_not_bottom_type(Unique_Node_List& worklist, Node* n) const; 621 void push_more_uses(Unique_Node_List& worklist, Node* parent, const Node* use) const; 622 void push_phis(Unique_Node_List& worklist, const Node* use) const; 623 static void push_catch(Unique_Node_List& worklist, const Node* use); 624 void push_cmpu(Unique_Node_List& worklist, const Node* use) const; 625 static void push_counted_loop_phi(Unique_Node_List& worklist, Node* parent, const Node* use); 626 static void push_cast(Unique_Node_List& worklist, const Node* use); 627 void push_loadp(Unique_Node_List& worklist, const Node* use) const; 628 static void push_load_barrier(Unique_Node_List& worklist, const BarrierSetC2* barrier_set, const Node* use); 629 void push_and(Unique_Node_List& worklist, const Node* parent, const Node* use) const; 630 void push_cast_ii(Unique_Node_List& worklist, const Node* parent, const Node* use) const; 631 void push_opaque_zero_trip_guard(Unique_Node_List& worklist, const Node* use) const; 632 633 public: 634 PhaseCCP( PhaseIterGVN *igvn ); // Compute conditional constants 635 NOT_PRODUCT( ~PhaseCCP(); ) 636 637 // Worklist algorithm identifies constants 638 void analyze(); 639 #ifdef ASSERT 640 void verify_type(Node* n, const Type* tnew, const Type* told); 641 // For every node n on verify list, check if type(n) == n->Value() 642 void verify_analyze(Unique_Node_List& worklist_verify); 643 #endif 644 // Recursive traversal of program. Used analysis to modify program. 645 virtual Node *transform( Node *n ); 646 // Do any transformation after analysis 647 void do_transform(); 648 649 virtual const Type* saturate(const Type* new_type, const Type* old_type, 650 const Type* limit_type) const; 651 // Returns new_type->widen(old_type), which increments the widen bits until 652 // giving up with TypeInt::INT or TypeLong::LONG. 653 // Result is clipped to limit_type if necessary. 654 virtual const Type* saturate_and_maybe_push_to_igvn_worklist(const TypeNode* n, const Type* new_type) { 655 const Type* t = saturate(new_type, type_or_null(n), n->type()); 656 if (t != new_type) { 657 // Type was widened in CCP, but IGVN may be able to make it narrower. 658 _worklist.push((Node*)n); 659 } 660 return t; 661 } 662 663 #ifndef PRODUCT 664 static uint _total_invokes; // For profiling, count invocations 665 void inc_invokes() { ++PhaseCCP::_total_invokes; } 666 667 static uint _total_constants; // For profiling, count constants found 668 uint _count_constants; 669 void clear_constants() { _count_constants = 0; } 670 void inc_constants() { ++_count_constants; } 671 uint count_constants() const { return _count_constants; } 672 673 static void print_statistics(); 674 #endif 675 }; 676 677 678 //------------------------------PhasePeephole---------------------------------- 679 // Phase for performing peephole optimizations on register allocated basic blocks. 680 class PhasePeephole : public PhaseTransform { 681 PhaseRegAlloc *_regalloc; 682 PhaseCFG &_cfg; 683 // Recursive traversal of program. Pure function is unused in this phase 684 virtual Node *transform( Node *n ); 685 686 public: 687 PhasePeephole( PhaseRegAlloc *regalloc, PhaseCFG &cfg ); 688 NOT_PRODUCT( ~PhasePeephole(); ) 689 690 // Do any transformation after analysis 691 void do_transform(); 692 693 #ifndef PRODUCT 694 static uint _total_peepholes; // For profiling, count peephole rules applied 695 uint _count_peepholes; 696 void clear_peepholes() { _count_peepholes = 0; } 697 void inc_peepholes() { ++_count_peepholes; } 698 uint count_peepholes() const { return _count_peepholes; } 699 700 static void print_statistics(); 701 #endif 702 }; 703 704 #endif // SHARE_OPTO_PHASEX_HPP