phaseX.cpp revision 6412:53a41e7cbe05
1169689Skan/* 2169689Skan * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved. 3169689Skan * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4169689Skan * 5169689Skan * This code is free software; you can redistribute it and/or modify it 6169689Skan * under the terms of the GNU General Public License version 2 only, as 7169689Skan * published by the Free Software Foundation. 8169689Skan * 9169689Skan * This code is distributed in the hope that it will be useful, but WITHOUT 10169689Skan * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11169689Skan * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12169689Skan * version 2 for more details (a copy is included in the LICENSE file that 13169689Skan * accompanied this code). 14169689Skan * 15169689Skan * You should have received a copy of the GNU General Public License version 16169689Skan * 2 along with this work; if not, write to the Free Software Foundation, 17169689Skan * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18169689Skan * 19169689Skan * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20169689Skan * or visit www.oracle.com if you need additional information or have any 21169689Skan * questions. 22169689Skan * 23169689Skan */ 24169689Skan 25169689Skan#include "precompiled.hpp" 26169689Skan#include "memory/allocation.inline.hpp" 27169689Skan#include "opto/block.hpp" 28169689Skan#include "opto/callnode.hpp" 29169689Skan#include "opto/cfgnode.hpp" 30169689Skan#include "opto/idealGraphPrinter.hpp" 31169689Skan#include "opto/loopnode.hpp" 32169689Skan#include "opto/machnode.hpp" 33169689Skan#include "opto/opcodes.hpp" 34169689Skan#include "opto/phaseX.hpp" 35169689Skan#include "opto/regalloc.hpp" 36169689Skan#include "opto/rootnode.hpp" 37169689Skan 38169689Skan//============================================================================= 39169689Skan#define NODE_HASH_MINIMUM_SIZE 255 40169689Skan//------------------------------NodeHash--------------------------------------- 41169689SkanNodeHash::NodeHash(uint est_max_size) : 42169689Skan _max( round_up(est_max_size < NODE_HASH_MINIMUM_SIZE ? NODE_HASH_MINIMUM_SIZE : est_max_size) ), 43169689Skan _a(Thread::current()->resource_area()), 44169689Skan _table( NEW_ARENA_ARRAY( _a , Node* , _max ) ), // (Node**)_a->Amalloc(_max * sizeof(Node*)) ), 45169689Skan _inserts(0), _insert_limit( insert_limit() ), 46169689Skan _look_probes(0), _lookup_hits(0), _lookup_misses(0), 47169689Skan _total_insert_probes(0), _total_inserts(0), 48169689Skan _insert_probes(0), _grows(0) { 49169689Skan // _sentinel must be in the current node space 50169689Skan _sentinel = new (Compile::current()) ProjNode(NULL, TypeFunc::Control); 51169689Skan memset(_table,0,sizeof(Node*)*_max); 52169689Skan} 53169689Skan 54169689Skan//------------------------------NodeHash--------------------------------------- 55169689SkanNodeHash::NodeHash(Arena *arena, uint est_max_size) : 56169689Skan _max( round_up(est_max_size < NODE_HASH_MINIMUM_SIZE ? NODE_HASH_MINIMUM_SIZE : est_max_size) ), 57169689Skan _a(arena), 58169689Skan _table( NEW_ARENA_ARRAY( _a , Node* , _max ) ), 59169689Skan _inserts(0), _insert_limit( insert_limit() ), 60169689Skan _look_probes(0), _lookup_hits(0), _lookup_misses(0), 61169689Skan _delete_probes(0), _delete_hits(0), _delete_misses(0), 62169689Skan _total_insert_probes(0), _total_inserts(0), 63169689Skan _insert_probes(0), _grows(0) { 64169689Skan // _sentinel must be in the current node space 65169689Skan _sentinel = new (Compile::current()) ProjNode(NULL, TypeFunc::Control); 66169689Skan memset(_table,0,sizeof(Node*)*_max); 67169689Skan} 68169689Skan 69169689Skan//------------------------------NodeHash--------------------------------------- 70169689SkanNodeHash::NodeHash(NodeHash *nh) { 71169689Skan debug_only(_table = (Node**)badAddress); // interact correctly w/ operator= 72169689Skan // just copy in all the fields 73169689Skan *this = *nh; 74169689Skan // nh->_sentinel must be in the current node space 75169689Skan} 76169689Skan 77169689Skanvoid NodeHash::replace_with(NodeHash *nh) { 78169689Skan debug_only(_table = (Node**)badAddress); // interact correctly w/ operator= 79169689Skan // just copy in all the fields 80169689Skan *this = *nh; 81169689Skan // nh->_sentinel must be in the current node space 82169689Skan} 83169689Skan 84169689Skan//------------------------------hash_find-------------------------------------- 85169689Skan// Find in hash table 86169689SkanNode *NodeHash::hash_find( const Node *n ) { 87169689Skan // ((Node*)n)->set_hash( n->hash() ); 88169689Skan uint hash = n->hash(); 89169689Skan if (hash == Node::NO_HASH) { 90169689Skan debug_only( _lookup_misses++ ); 91169689Skan return NULL; 92169689Skan } 93169689Skan uint key = hash & (_max-1); 94169689Skan uint stride = key | 0x01; 95169689Skan debug_only( _look_probes++ ); 96169689Skan Node *k = _table[key]; // Get hashed value 97169689Skan if( !k ) { // ?Miss? 98169689Skan debug_only( _lookup_misses++ ); 99169689Skan return NULL; // Miss! 100169689Skan } 101169689Skan 102169689Skan int op = n->Opcode(); 103169689Skan uint req = n->req(); 104169689Skan while( 1 ) { // While probing hash table 105169689Skan if( k->req() == req && // Same count of inputs 106169689Skan k->Opcode() == op ) { // Same Opcode 107169689Skan for( uint i=0; i<req; i++ ) 108169689Skan if( n->in(i)!=k->in(i)) // Different inputs? 109169689Skan goto collision; // "goto" is a speed hack... 110169689Skan if( n->cmp(*k) ) { // Check for any special bits 111169689Skan debug_only( _lookup_hits++ ); 112169689Skan return k; // Hit! 113169689Skan } 114169689Skan } 115169689Skan collision: 116169689Skan debug_only( _look_probes++ ); 117169689Skan key = (key + stride/*7*/) & (_max-1); // Stride through table with relative prime 118169689Skan k = _table[key]; // Get hashed value 119169689Skan if( !k ) { // ?Miss? 120169689Skan debug_only( _lookup_misses++ ); 121169689Skan return NULL; // Miss! 122169689Skan } 123169689Skan } 124169689Skan ShouldNotReachHere(); 125169689Skan return NULL; 126169689Skan} 127169689Skan 128169689Skan//------------------------------hash_find_insert------------------------------- 129169689Skan// Find in hash table, insert if not already present 130169689Skan// Used to preserve unique entries in hash table 131169689SkanNode *NodeHash::hash_find_insert( Node *n ) { 132169689Skan // n->set_hash( ); 133169689Skan uint hash = n->hash(); 134169689Skan if (hash == Node::NO_HASH) { 135169689Skan debug_only( _lookup_misses++ ); 136169689Skan return NULL; 137169689Skan } 138169689Skan uint key = hash & (_max-1); 139169689Skan uint stride = key | 0x01; // stride must be relatively prime to table siz 140169689Skan uint first_sentinel = 0; // replace a sentinel if seen. 141169689Skan debug_only( _look_probes++ ); 142169689Skan Node *k = _table[key]; // Get hashed value 143169689Skan if( !k ) { // ?Miss? 144169689Skan debug_only( _lookup_misses++ ); 145169689Skan _table[key] = n; // Insert into table! 146169689Skan debug_only(n->enter_hash_lock()); // Lock down the node while in the table. 147169689Skan check_grow(); // Grow table if insert hit limit 148169689Skan return NULL; // Miss! 149169689Skan } 150169689Skan else if( k == _sentinel ) { 151169689Skan first_sentinel = key; // Can insert here 152169689Skan } 153169689Skan 154169689Skan int op = n->Opcode(); 155169689Skan uint req = n->req(); 156169689Skan while( 1 ) { // While probing hash table 157169689Skan if( k->req() == req && // Same count of inputs 158169689Skan k->Opcode() == op ) { // Same Opcode 159169689Skan for( uint i=0; i<req; i++ ) 160169689Skan if( n->in(i)!=k->in(i)) // Different inputs? 161169689Skan goto collision; // "goto" is a speed hack... 162169689Skan if( n->cmp(*k) ) { // Check for any special bits 163169689Skan debug_only( _lookup_hits++ ); 164169689Skan return k; // Hit! 165169689Skan } 166169689Skan } 167169689Skan collision: 168169689Skan debug_only( _look_probes++ ); 169169689Skan key = (key + stride) & (_max-1); // Stride through table w/ relative prime 170169689Skan k = _table[key]; // Get hashed value 171169689Skan if( !k ) { // ?Miss? 172169689Skan debug_only( _lookup_misses++ ); 173169689Skan key = (first_sentinel == 0) ? key : first_sentinel; // ?saw sentinel? 174169689Skan _table[key] = n; // Insert into table! 175169689Skan debug_only(n->enter_hash_lock()); // Lock down the node while in the table. 176169689Skan check_grow(); // Grow table if insert hit limit 177169689Skan return NULL; // Miss! 178169689Skan } 179169689Skan else if( first_sentinel == 0 && k == _sentinel ) { 180169689Skan first_sentinel = key; // Can insert here 181169689Skan } 182169689Skan 183169689Skan } 184169689Skan ShouldNotReachHere(); 185169689Skan return NULL; 186169689Skan} 187169689Skan 188169689Skan//------------------------------hash_insert------------------------------------ 189169689Skan// Insert into hash table 190169689Skanvoid NodeHash::hash_insert( Node *n ) { 191169689Skan // // "conflict" comments -- print nodes that conflict 192169689Skan // bool conflict = false; 193169689Skan // n->set_hash(); 194169689Skan uint hash = n->hash(); 195169689Skan if (hash == Node::NO_HASH) { 196169689Skan return; 197169689Skan } 198169689Skan check_grow(); 199169689Skan uint key = hash & (_max-1); 200169689Skan uint stride = key | 0x01; 201169689Skan 202169689Skan while( 1 ) { // While probing hash table 203169689Skan debug_only( _insert_probes++ ); 204169689Skan Node *k = _table[key]; // Get hashed value 205169689Skan if( !k || (k == _sentinel) ) break; // Found a slot 206169689Skan assert( k != n, "already inserted" ); 207169689Skan // if( PrintCompilation && PrintOptoStatistics && Verbose ) { tty->print(" conflict: "); k->dump(); conflict = true; } 208169689Skan key = (key + stride) & (_max-1); // Stride through table w/ relative prime 209169689Skan } 210169689Skan _table[key] = n; // Insert into table! 211169689Skan debug_only(n->enter_hash_lock()); // Lock down the node while in the table. 212169689Skan // if( conflict ) { n->dump(); } 213169689Skan} 214169689Skan 215169689Skan//------------------------------hash_delete------------------------------------ 216169689Skan// Replace in hash table with sentinel 217169689Skanbool NodeHash::hash_delete( const Node *n ) { 218169689Skan Node *k; 219169689Skan uint hash = n->hash(); 220169689Skan if (hash == Node::NO_HASH) { 221169689Skan debug_only( _delete_misses++ ); 222169689Skan return false; 223169689Skan } 224169689Skan uint key = hash & (_max-1); 225169689Skan uint stride = key | 0x01; 226169689Skan debug_only( uint counter = 0; ); 227169689Skan for( ; /* (k != NULL) && (k != _sentinel) */; ) { 228169689Skan debug_only( counter++ ); 229169689Skan debug_only( _delete_probes++ ); 230169689Skan k = _table[key]; // Get hashed value 231169689Skan if( !k ) { // Miss? 232169689Skan debug_only( _delete_misses++ ); 233169689Skan#ifdef ASSERT 234169689Skan if( VerifyOpto ) { 235169689Skan for( uint i=0; i < _max; i++ ) 236169689Skan assert( _table[i] != n, "changed edges with rehashing" ); 237169689Skan } 238169689Skan#endif 239169689Skan return false; // Miss! Not in chain 240169689Skan } 241169689Skan else if( n == k ) { 242169689Skan debug_only( _delete_hits++ ); 243169689Skan _table[key] = _sentinel; // Hit! Label as deleted entry 244169689Skan debug_only(((Node*)n)->exit_hash_lock()); // Unlock the node upon removal from table. 245169689Skan return true; 246169689Skan } 247169689Skan else { 248169689Skan // collision: move through table with prime offset 249169689Skan key = (key + stride/*7*/) & (_max-1); 250169689Skan assert( counter <= _insert_limit, "Cycle in hash-table"); 251169689Skan } 252169689Skan } 253169689Skan ShouldNotReachHere(); 254169689Skan return false; 255169689Skan} 256169689Skan 257169689Skan//------------------------------round_up--------------------------------------- 258169689Skan// Round up to nearest power of 2 259169689Skanuint NodeHash::round_up( uint x ) { 260169689Skan x += (x>>2); // Add 25% slop 261169689Skan if( x <16 ) return 16; // Small stuff 262169689Skan uint i=16; 263169689Skan while( i < x ) i <<= 1; // Double to fit 264169689Skan return i; // Return hash table size 265169689Skan} 266169689Skan 267169689Skan//------------------------------grow------------------------------------------- 268169689Skan// Grow _table to next power of 2 and insert old entries 269169689Skanvoid NodeHash::grow() { 270169689Skan // Record old state 271169689Skan uint old_max = _max; 272169689Skan Node **old_table = _table; 273169689Skan // Construct new table with twice the space 274169689Skan _grows++; 275169689Skan _total_inserts += _inserts; 276169689Skan _total_insert_probes += _insert_probes; 277169689Skan _inserts = 0; 278169689Skan _insert_probes = 0; 279169689Skan _max = _max << 1; 280169689Skan _table = NEW_ARENA_ARRAY( _a , Node* , _max ); // (Node**)_a->Amalloc( _max * sizeof(Node*) ); 281169689Skan memset(_table,0,sizeof(Node*)*_max); 282169689Skan _insert_limit = insert_limit(); 283169689Skan // Insert old entries into the new table 284169689Skan for( uint i = 0; i < old_max; i++ ) { 285169689Skan Node *m = *old_table++; 286169689Skan if( !m || m == _sentinel ) continue; 287169689Skan debug_only(m->exit_hash_lock()); // Unlock the node upon removal from old table. 288169689Skan hash_insert(m); 289169689Skan } 290169689Skan} 291169689Skan 292169689Skan//------------------------------clear------------------------------------------ 293169689Skan// Clear all entries in _table to NULL but keep storage 294169689Skanvoid NodeHash::clear() { 295169689Skan#ifdef ASSERT 296169689Skan // Unlock all nodes upon removal from table. 297169689Skan for (uint i = 0; i < _max; i++) { 298169689Skan Node* n = _table[i]; 299169689Skan if (!n || n == _sentinel) continue; 300169689Skan n->exit_hash_lock(); 301169689Skan } 302169689Skan#endif 303169689Skan 304169689Skan memset( _table, 0, _max * sizeof(Node*) ); 305169689Skan} 306169689Skan 307169689Skan//-----------------------remove_useless_nodes---------------------------------- 308169689Skan// Remove useless nodes from value table, 309169689Skan// implementation does not depend on hash function 310169689Skanvoid NodeHash::remove_useless_nodes(VectorSet &useful) { 311169689Skan 312169689Skan // Dead nodes in the hash table inherited from GVN should not replace 313169689Skan // existing nodes, remove dead nodes. 314169689Skan uint max = size(); 315169689Skan Node *sentinel_node = sentinel(); 316169689Skan for( uint i = 0; i < max; ++i ) { 317169689Skan Node *n = at(i); 318169689Skan if(n != NULL && n != sentinel_node && !useful.test(n->_idx)) { 319169689Skan debug_only(n->exit_hash_lock()); // Unlock the node when removed 320169689Skan _table[i] = sentinel_node; // Replace with placeholder 321169689Skan } 322169689Skan } 323169689Skan} 324169689Skan 325169689Skan 326169689Skanvoid NodeHash::check_no_speculative_types() { 327169689Skan#ifdef ASSERT 328169689Skan uint max = size(); 329169689Skan Node *sentinel_node = sentinel(); 330169689Skan for (uint i = 0; i < max; ++i) { 331169689Skan Node *n = at(i); 332169689Skan if(n != NULL && n != sentinel_node && n->is_Type() && n->outcnt() > 0) { 333169689Skan TypeNode* tn = n->as_Type(); 334169689Skan const Type* t = tn->type(); 335169689Skan const Type* t_no_spec = t->remove_speculative(); 336169689Skan assert(t == t_no_spec, "dead node in hash table or missed node during speculative cleanup"); 337169689Skan } 338169689Skan } 339169689Skan#endif 340169689Skan} 341169689Skan 342169689Skan#ifndef PRODUCT 343169689Skan//------------------------------dump------------------------------------------- 344169689Skan// Dump statistics for the hash table 345169689Skanvoid NodeHash::dump() { 346169689Skan _total_inserts += _inserts; 347169689Skan _total_insert_probes += _insert_probes; 348169689Skan if (PrintCompilation && PrintOptoStatistics && Verbose && (_inserts > 0)) { 349169689Skan if (WizardMode) { 350169689Skan for (uint i=0; i<_max; i++) { 351169689Skan if (_table[i]) 352169689Skan tty->print("%d/%d/%d ",i,_table[i]->hash()&(_max-1),_table[i]->_idx); 353169689Skan } 354169689Skan } 355169689Skan tty->print("\nGVN Hash stats: %d grows to %d max_size\n", _grows, _max); 356169689Skan tty->print(" %d/%d (%8.1f%% full)\n", _inserts, _max, (double)_inserts/_max*100.0); 357169689Skan tty->print(" %dp/(%dh+%dm) (%8.2f probes/lookup)\n", _look_probes, _lookup_hits, _lookup_misses, (double)_look_probes/(_lookup_hits+_lookup_misses)); 358169689Skan tty->print(" %dp/%di (%8.2f probes/insert)\n", _total_insert_probes, _total_inserts, (double)_total_insert_probes/_total_inserts); 359169689Skan // sentinels increase lookup cost, but not insert cost 360169689Skan assert((_lookup_misses+_lookup_hits)*4+100 >= _look_probes, "bad hash function"); 361169689Skan assert( _inserts+(_inserts>>3) < _max, "table too full" ); 362169689Skan assert( _inserts*3+100 >= _insert_probes, "bad hash function" ); 363169689Skan } 364169689Skan} 365169689Skan 366169689SkanNode *NodeHash::find_index(uint idx) { // For debugging 367169689Skan // Find an entry by its index value 368169689Skan for( uint i = 0; i < _max; i++ ) { 369169689Skan Node *m = _table[i]; 370169689Skan if( !m || m == _sentinel ) continue; 371169689Skan if( m->_idx == (uint)idx ) return m; 372169689Skan } 373169689Skan return NULL; 374169689Skan} 375169689Skan#endif 376169689Skan 377169689Skan#ifdef ASSERT 378169689SkanNodeHash::~NodeHash() { 379169689Skan // Unlock all nodes upon destruction of table. 380169689Skan if (_table != (Node**)badAddress) clear(); 381169689Skan} 382169689Skan 383169689Skanvoid NodeHash::operator=(const NodeHash& nh) { 384169689Skan // Unlock all nodes upon replacement of table. 385169689Skan if (&nh == this) return; 386169689Skan if (_table != (Node**)badAddress) clear(); 387169689Skan memcpy(this, &nh, sizeof(*this)); 388169689Skan // Do not increment hash_lock counts again. 389169689Skan // Instead, be sure we never again use the source table. 390169689Skan ((NodeHash*)&nh)->_table = (Node**)badAddress; 391169689Skan} 392169689Skan 393169689Skan 394169689Skan#endif 395169689Skan 396169689Skan 397169689Skan//============================================================================= 398169689Skan//------------------------------PhaseRemoveUseless----------------------------- 399169689Skan// 1) Use a breadthfirst walk to collect useful nodes reachable from root. 400169689SkanPhaseRemoveUseless::PhaseRemoveUseless( PhaseGVN *gvn, Unique_Node_List *worklist ) : Phase(Remove_Useless), 401169689Skan _useful(Thread::current()->resource_area()) { 402169689Skan 403169689Skan // Implementation requires 'UseLoopSafepoints == true' and an edge from root 404169689Skan // to each SafePointNode at a backward branch. Inserted in add_safepoint(). 405169689Skan if( !UseLoopSafepoints || !OptoRemoveUseless ) return; 406169689Skan 407169689Skan // Identify nodes that are reachable from below, useful. 408169689Skan C->identify_useful_nodes(_useful); 409169689Skan // Update dead node list 410169689Skan C->update_dead_node_list(_useful); 411169689Skan 412169689Skan // Remove all useless nodes from PhaseValues' recorded types 413169689Skan // Must be done before disconnecting nodes to preserve hash-table-invariant 414169689Skan gvn->remove_useless_nodes(_useful.member_set()); 415169689Skan 416169689Skan // Remove all useless nodes from future worklist 417169689Skan worklist->remove_useless_nodes(_useful.member_set()); 418169689Skan 419169689Skan // Disconnect 'useless' nodes that are adjacent to useful nodes 420169689Skan C->remove_useless_nodes(_useful); 421169689Skan 422169689Skan // Remove edges from "root" to each SafePoint at a backward branch. 423169689Skan // They were inserted during parsing (see add_safepoint()) to make infinite 424169689Skan // loops without calls or exceptions visible to root, i.e., useful. 425169689Skan Node *root = C->root(); 426169689Skan if( root != NULL ) { 427169689Skan for( uint i = root->req(); i < root->len(); ++i ) { 428169689Skan Node *n = root->in(i); 429169689Skan if( n != NULL && n->is_SafePoint() ) { 430169689Skan root->rm_prec(i); 431169689Skan --i; 432169689Skan } 433169689Skan } 434169689Skan } 435169689Skan} 436169689Skan 437169689Skan 438169689Skan//============================================================================= 439169689Skan//------------------------------PhaseTransform--------------------------------- 440169689SkanPhaseTransform::PhaseTransform( PhaseNumber pnum ) : Phase(pnum), 441169689Skan _arena(Thread::current()->resource_area()), 442169689Skan _nodes(_arena), 443169689Skan _types(_arena) 444169689Skan{ 445169689Skan init_con_caches(); 446169689Skan#ifndef PRODUCT 447169689Skan clear_progress(); 448169689Skan clear_transforms(); 449169689Skan set_allow_progress(true); 450169689Skan#endif 451169689Skan // Force allocation for currently existing nodes 452169689Skan _types.map(C->unique(), NULL); 453169689Skan} 454169689Skan 455169689Skan//------------------------------PhaseTransform--------------------------------- 456169689SkanPhaseTransform::PhaseTransform( Arena *arena, PhaseNumber pnum ) : Phase(pnum), 457169689Skan _arena(arena), 458169689Skan _nodes(arena), 459169689Skan _types(arena) 460169689Skan{ 461169689Skan init_con_caches(); 462169689Skan#ifndef PRODUCT 463169689Skan clear_progress(); 464169689Skan clear_transforms(); 465169689Skan set_allow_progress(true); 466169689Skan#endif 467169689Skan // Force allocation for currently existing nodes 468169689Skan _types.map(C->unique(), NULL); 469169689Skan} 470169689Skan 471169689Skan//------------------------------PhaseTransform--------------------------------- 472169689Skan// Initialize with previously generated type information 473169689SkanPhaseTransform::PhaseTransform( PhaseTransform *pt, PhaseNumber pnum ) : Phase(pnum), 474169689Skan _arena(pt->_arena), 475169689Skan _nodes(pt->_nodes), 476169689Skan _types(pt->_types) 477169689Skan{ 478169689Skan init_con_caches(); 479169689Skan#ifndef PRODUCT 480169689Skan clear_progress(); 481169689Skan clear_transforms(); 482169689Skan set_allow_progress(true); 483169689Skan#endif 484169689Skan} 485169689Skan 486169689Skanvoid PhaseTransform::init_con_caches() { 487169689Skan memset(_icons,0,sizeof(_icons)); 488169689Skan memset(_lcons,0,sizeof(_lcons)); 489169689Skan memset(_zcons,0,sizeof(_zcons)); 490169689Skan} 491169689Skan 492169689Skan 493169689Skan//--------------------------------find_int_type-------------------------------- 494169689Skanconst TypeInt* PhaseTransform::find_int_type(Node* n) { 495169689Skan if (n == NULL) return NULL; 496169689Skan // Call type_or_null(n) to determine node's type since we might be in 497169689Skan // parse phase and call n->Value() may return wrong type. 498169689Skan // (For example, a phi node at the beginning of loop parsing is not ready.) 499169689Skan const Type* t = type_or_null(n); 500169689Skan if (t == NULL) return NULL; 501169689Skan return t->isa_int(); 502169689Skan} 503169689Skan 504169689Skan 505169689Skan//-------------------------------find_long_type-------------------------------- 506169689Skanconst TypeLong* PhaseTransform::find_long_type(Node* n) { 507169689Skan if (n == NULL) return NULL; 508169689Skan // (See comment above on type_or_null.) 509169689Skan const Type* t = type_or_null(n); 510169689Skan if (t == NULL) return NULL; 511169689Skan return t->isa_long(); 512169689Skan} 513169689Skan 514169689Skan 515169689Skan#ifndef PRODUCT 516169689Skanvoid PhaseTransform::dump_old2new_map() const { 517169689Skan _nodes.dump(); 518169689Skan} 519169689Skan 520169689Skanvoid PhaseTransform::dump_new( uint nidx ) const { 521169689Skan for( uint i=0; i<_nodes.Size(); i++ ) 522169689Skan if( _nodes[i] && _nodes[i]->_idx == nidx ) { 523169689Skan _nodes[i]->dump(); 524169689Skan tty->cr(); 525169689Skan tty->print_cr("Old index= %d",i); 526169689Skan return; 527169689Skan } 528169689Skan tty->print_cr("Node %d not found in the new indices", nidx); 529169689Skan} 530169689Skan 531169689Skan//------------------------------dump_types------------------------------------- 532169689Skanvoid PhaseTransform::dump_types( ) const { 533169689Skan _types.dump(); 534169689Skan} 535169689Skan 536169689Skan//------------------------------dump_nodes_and_types--------------------------- 537169689Skanvoid PhaseTransform::dump_nodes_and_types(const Node *root, uint depth, bool only_ctrl) { 538169689Skan VectorSet visited(Thread::current()->resource_area()); 539169689Skan dump_nodes_and_types_recur( root, depth, only_ctrl, visited ); 540169689Skan} 541169689Skan 542169689Skan//------------------------------dump_nodes_and_types_recur--------------------- 543169689Skanvoid PhaseTransform::dump_nodes_and_types_recur( const Node *n, uint depth, bool only_ctrl, VectorSet &visited) { 544169689Skan if( !n ) return; 545169689Skan if( depth == 0 ) return; 546169689Skan if( visited.test_set(n->_idx) ) return; 547169689Skan for( uint i=0; i<n->len(); i++ ) { 548169689Skan if( only_ctrl && !(n->is_Region()) && i != TypeFunc::Control ) continue; 549169689Skan dump_nodes_and_types_recur( n->in(i), depth-1, only_ctrl, visited ); 550169689Skan } 551169689Skan n->dump(); 552169689Skan if (type_or_null(n) != NULL) { 553169689Skan tty->print(" "); type(n)->dump(); tty->cr(); 554169689Skan } 555169689Skan} 556169689Skan 557169689Skan#endif 558169689Skan 559169689Skan 560169689Skan//============================================================================= 561169689Skan//------------------------------PhaseValues------------------------------------ 562169689Skan// Set minimum table size to "255" 563169689SkanPhaseValues::PhaseValues( Arena *arena, uint est_max_size ) : PhaseTransform(arena, GVN), _table(arena, est_max_size) { 564169689Skan NOT_PRODUCT( clear_new_values(); ) 565169689Skan} 566169689Skan 567169689Skan//------------------------------PhaseValues------------------------------------ 568169689Skan// Set minimum table size to "255" 569169689SkanPhaseValues::PhaseValues( PhaseValues *ptv ) : PhaseTransform( ptv, GVN ), 570169689Skan _table(&ptv->_table) { 571169689Skan NOT_PRODUCT( clear_new_values(); ) 572169689Skan} 573169689Skan 574169689Skan//------------------------------PhaseValues------------------------------------ 575169689Skan// Used by +VerifyOpto. Clear out hash table but copy _types array. 576169689SkanPhaseValues::PhaseValues( PhaseValues *ptv, const char *dummy ) : PhaseTransform( ptv, GVN ), 577169689Skan _table(ptv->arena(),ptv->_table.size()) { 578169689Skan NOT_PRODUCT( clear_new_values(); ) 579169689Skan} 580169689Skan 581169689Skan//------------------------------~PhaseValues----------------------------------- 582169689Skan#ifndef PRODUCT 583169689SkanPhaseValues::~PhaseValues() { 584169689Skan _table.dump(); 585169689Skan 586169689Skan // Statistics for value progress and efficiency 587169689Skan if( PrintCompilation && Verbose && WizardMode ) { 588169689Skan tty->print("\n%sValues: %d nodes ---> %d/%d (%d)", 589169689Skan is_IterGVN() ? "Iter" : " ", C->unique(), made_progress(), made_transforms(), made_new_values()); 590169689Skan if( made_transforms() != 0 ) { 591169689Skan tty->print_cr(" ratio %f", made_progress()/(float)made_transforms() ); 592169689Skan } else { 593169689Skan tty->cr(); 594169689Skan } 595169689Skan } 596169689Skan} 597169689Skan#endif 598169689Skan 599169689Skan//------------------------------makecon---------------------------------------- 600169689SkanConNode* PhaseTransform::makecon(const Type *t) { 601169689Skan assert(t->singleton(), "must be a constant"); 602169689Skan assert(!t->empty() || t == Type::TOP, "must not be vacuous range"); 603169689Skan switch (t->base()) { // fast paths 604169689Skan case Type::Half: 605169689Skan case Type::Top: return (ConNode*) C->top(); 606169689Skan case Type::Int: return intcon( t->is_int()->get_con() ); 607169689Skan case Type::Long: return longcon( t->is_long()->get_con() ); 608169689Skan } 609169689Skan if (t->is_zero_type()) 610169689Skan return zerocon(t->basic_type()); 611169689Skan return uncached_makecon(t); 612169689Skan} 613169689Skan 614169689Skan//--------------------------uncached_makecon----------------------------------- 615169689Skan// Make an idealized constant - one of ConINode, ConPNode, etc. 616169689SkanConNode* PhaseValues::uncached_makecon(const Type *t) { 617169689Skan assert(t->singleton(), "must be a constant"); 618169689Skan ConNode* x = ConNode::make(C, t); 619169689Skan ConNode* k = (ConNode*)hash_find_insert(x); // Value numbering 620169689Skan if (k == NULL) { 621169689Skan set_type(x, t); // Missed, provide type mapping 622169689Skan GrowableArray<Node_Notes*>* nna = C->node_note_array(); 623169689Skan if (nna != NULL) { 624169689Skan Node_Notes* loc = C->locate_node_notes(nna, x->_idx, true); 625169689Skan loc->clear(); // do not put debug info on constants 626169689Skan } 627169689Skan } else { 628169689Skan x->destruct(); // Hit, destroy duplicate constant 629169689Skan x = k; // use existing constant 630169689Skan } 631169689Skan return x; 632169689Skan} 633169689Skan 634169689Skan//------------------------------intcon----------------------------------------- 635169689Skan// Fast integer constant. Same as "transform(new ConINode(TypeInt::make(i)))" 636169689SkanConINode* PhaseTransform::intcon(int i) { 637169689Skan // Small integer? Check cache! Check that cached node is not dead 638169689Skan if (i >= _icon_min && i <= _icon_max) { 639169689Skan ConINode* icon = _icons[i-_icon_min]; 640169689Skan if (icon != NULL && icon->in(TypeFunc::Control) != NULL) 641169689Skan return icon; 642169689Skan } 643169689Skan ConINode* icon = (ConINode*) uncached_makecon(TypeInt::make(i)); 644169689Skan assert(icon->is_Con(), ""); 645169689Skan if (i >= _icon_min && i <= _icon_max) 646169689Skan _icons[i-_icon_min] = icon; // Cache small integers 647169689Skan return icon; 648169689Skan} 649169689Skan 650169689Skan//------------------------------longcon---------------------------------------- 651169689Skan// Fast long constant. 652169689SkanConLNode* PhaseTransform::longcon(jlong l) { 653169689Skan // Small integer? Check cache! Check that cached node is not dead 654169689Skan if (l >= _lcon_min && l <= _lcon_max) { 655169689Skan ConLNode* lcon = _lcons[l-_lcon_min]; 656169689Skan if (lcon != NULL && lcon->in(TypeFunc::Control) != NULL) 657169689Skan return lcon; 658169689Skan } 659169689Skan ConLNode* lcon = (ConLNode*) uncached_makecon(TypeLong::make(l)); 660169689Skan assert(lcon->is_Con(), ""); 661169689Skan if (l >= _lcon_min && l <= _lcon_max) 662169689Skan _lcons[l-_lcon_min] = lcon; // Cache small integers 663169689Skan return lcon; 664169689Skan} 665169689Skan 666169689Skan//------------------------------zerocon----------------------------------------- 667169689Skan// Fast zero or null constant. Same as "transform(ConNode::make(Type::get_zero_type(bt)))" 668169689SkanConNode* PhaseTransform::zerocon(BasicType bt) { 669169689Skan assert((uint)bt <= _zcon_max, "domain check"); 670169689Skan ConNode* zcon = _zcons[bt]; 671169689Skan if (zcon != NULL && zcon->in(TypeFunc::Control) != NULL) 672169689Skan return zcon; 673169689Skan zcon = (ConNode*) uncached_makecon(Type::get_zero_type(bt)); 674169689Skan _zcons[bt] = zcon; 675169689Skan return zcon; 676169689Skan} 677169689Skan 678169689Skan 679169689Skan 680169689Skan//============================================================================= 681169689Skan//------------------------------transform-------------------------------------- 682169689Skan// Return a node which computes the same function as this node, but in a 683169689Skan// faster or cheaper fashion. 684169689SkanNode *PhaseGVN::transform( Node *n ) { 685169689Skan return transform_no_reclaim(n); 686169689Skan} 687169689Skan 688169689Skan//------------------------------transform-------------------------------------- 689169689Skan// Return a node which computes the same function as this node, but 690169689Skan// in a faster or cheaper fashion. 691169689SkanNode *PhaseGVN::transform_no_reclaim( Node *n ) { 692169689Skan NOT_PRODUCT( set_transforms(); ) 693169689Skan 694169689Skan // Apply the Ideal call in a loop until it no longer applies 695169689Skan Node *k = n; 696169689Skan NOT_PRODUCT( uint loop_count = 0; ) 697169689Skan while( 1 ) { 698169689Skan Node *i = k->Ideal(this, /*can_reshape=*/false); 699169689Skan if( !i ) break; 700169689Skan assert( i->_idx >= k->_idx, "Idealize should return new nodes, use Identity to return old nodes" ); 701169689Skan k = i; 702169689Skan assert(loop_count++ < K, "infinite loop in PhaseGVN::transform"); 703169689Skan } 704169689Skan NOT_PRODUCT( if( loop_count != 0 ) { set_progress(); } ) 705169689Skan 706169689Skan 707169689Skan // If brand new node, make space in type array. 708169689Skan ensure_type_or_null(k); 709169689Skan 710169689Skan // Since I just called 'Value' to compute the set of run-time values 711169689Skan // for this Node, and 'Value' is non-local (and therefore expensive) I'll 712169689Skan // cache Value. Later requests for the local phase->type of this Node can 713169689Skan // use the cached Value instead of suffering with 'bottom_type'. 714169689Skan const Type *t = k->Value(this); // Get runtime Value set 715169689Skan assert(t != NULL, "value sanity"); 716169689Skan if (type_or_null(k) != t) { 717169689Skan#ifndef PRODUCT 718169689Skan // Do not count initial visit to node as a transformation 719169689Skan if (type_or_null(k) == NULL) { 720169689Skan inc_new_values(); 721169689Skan set_progress(); 722169689Skan } 723169689Skan#endif 724169689Skan set_type(k, t); 725169689Skan // If k is a TypeNode, capture any more-precise type permanently into Node 726169689Skan k->raise_bottom_type(t); 727169689Skan } 728169689Skan 729169689Skan if( t->singleton() && !k->is_Con() ) { 730169689Skan NOT_PRODUCT( set_progress(); ) 731169689Skan return makecon(t); // Turn into a constant 732169689Skan } 733169689Skan 734169689Skan // Now check for Identities 735169689Skan Node *i = k->Identity(this); // Look for a nearby replacement 736169689Skan if( i != k ) { // Found? Return replacement! 737169689Skan NOT_PRODUCT( set_progress(); ) 738169689Skan return i; 739169689Skan } 740169689Skan 741169689Skan // Global Value Numbering 742169689Skan i = hash_find_insert(k); // Insert if new 743169689Skan if( i && (i != k) ) { 744169689Skan // Return the pre-existing node 745169689Skan NOT_PRODUCT( set_progress(); ) 746169689Skan return i; 747169689Skan } 748169689Skan 749169689Skan // Return Idealized original 750169689Skan return k; 751169689Skan} 752169689Skan 753169689Skan#ifdef ASSERT 754169689Skan//------------------------------dead_loop_check-------------------------------- 755169689Skan// Check for a simple dead loop when a data node references itself directly 756169689Skan// or through an other data node excluding cons and phis. 757169689Skanvoid PhaseGVN::dead_loop_check( Node *n ) { 758169689Skan // Phi may reference itself in a loop 759169689Skan if (n != NULL && !n->is_dead_loop_safe() && !n->is_CFG()) { 760169689Skan // Do 2 levels check and only data inputs. 761169689Skan bool no_dead_loop = true; 762169689Skan uint cnt = n->req(); 763169689Skan for (uint i = 1; i < cnt && no_dead_loop; i++) { 764169689Skan Node *in = n->in(i); 765169689Skan if (in == n) { 766169689Skan no_dead_loop = false; 767169689Skan } else if (in != NULL && !in->is_dead_loop_safe()) { 768169689Skan uint icnt = in->req(); 769169689Skan for (uint j = 1; j < icnt && no_dead_loop; j++) { 770169689Skan if (in->in(j) == n || in->in(j) == in) 771169689Skan no_dead_loop = false; 772169689Skan } 773169689Skan } 774169689Skan } 775169689Skan if (!no_dead_loop) n->dump(3); 776169689Skan assert(no_dead_loop, "dead loop detected"); 777169689Skan } 778169689Skan} 779169689Skan#endif 780169689Skan 781169689Skan//============================================================================= 782169689Skan//------------------------------PhaseIterGVN----------------------------------- 783169689Skan// Initialize hash table to fresh and clean for +VerifyOpto 784169689SkanPhaseIterGVN::PhaseIterGVN( PhaseIterGVN *igvn, const char *dummy ) : PhaseGVN(igvn,dummy), _worklist( ), 785169689Skan _stack(C->unique() >> 1), 786169689Skan _delay_transform(false) { 787169689Skan} 788169689Skan 789169689Skan//------------------------------PhaseIterGVN----------------------------------- 790169689Skan// Initialize with previous PhaseIterGVN info; used by PhaseCCP 791169689SkanPhaseIterGVN::PhaseIterGVN( PhaseIterGVN *igvn ) : PhaseGVN(igvn), 792169689Skan _worklist( igvn->_worklist ), 793169689Skan _stack( igvn->_stack ), 794169689Skan _delay_transform(igvn->_delay_transform) 795169689Skan{ 796169689Skan} 797169689Skan 798169689Skan//------------------------------PhaseIterGVN----------------------------------- 799169689Skan// Initialize with previous PhaseGVN info from Parser 800169689SkanPhaseIterGVN::PhaseIterGVN( PhaseGVN *gvn ) : PhaseGVN(gvn), 801169689Skan _worklist(*C->for_igvn()), 802169689Skan _stack(C->unique() >> 1), 803169689Skan _delay_transform(false) 804169689Skan{ 805169689Skan uint max; 806169689Skan 807169689Skan // Dead nodes in the hash table inherited from GVN were not treated as 808169689Skan // roots during def-use info creation; hence they represent an invisible 809169689Skan // use. Clear them out. 810169689Skan max = _table.size(); 811169689Skan for( uint i = 0; i < max; ++i ) { 812169689Skan Node *n = _table.at(i); 813169689Skan if(n != NULL && n != _table.sentinel() && n->outcnt() == 0) { 814169689Skan if( n->is_top() ) continue; 815169689Skan assert( false, "Parse::remove_useless_nodes missed this node"); 816169689Skan hash_delete(n); 817169689Skan } 818169689Skan } 819169689Skan 820169689Skan // Any Phis or Regions on the worklist probably had uses that could not 821169689Skan // make more progress because the uses were made while the Phis and Regions 822169689Skan // were in half-built states. Put all uses of Phis and Regions on worklist. 823169689Skan max = _worklist.size(); 824169689Skan for( uint j = 0; j < max; j++ ) { 825169689Skan Node *n = _worklist.at(j); 826169689Skan uint uop = n->Opcode(); 827169689Skan if( uop == Op_Phi || uop == Op_Region || 828169689Skan n->is_Type() || 829169689Skan n->is_Mem() ) 830169689Skan add_users_to_worklist(n); 831169689Skan } 832169689Skan} 833169689Skan 834169689Skan/** 835169689Skan * Initialize worklist for each node. 836169689Skan */ 837169689Skanvoid PhaseIterGVN::init_worklist(Node* first) { 838169689Skan Unique_Node_List to_process; 839169689Skan to_process.push(first); 840169689Skan 841169689Skan while (to_process.size() > 0) { 842169689Skan Node* n = to_process.pop(); 843169689Skan if (!_worklist.member(n)) { 844169689Skan _worklist.push(n); 845169689Skan 846169689Skan uint cnt = n->req(); 847169689Skan for(uint i = 0; i < cnt; i++) { 848169689Skan Node* m = n->in(i); 849169689Skan if (m != NULL) { 850169689Skan to_process.push(m); 851169689Skan } 852169689Skan } 853169689Skan } 854169689Skan } 855169689Skan} 856169689Skan 857169689Skan#ifndef PRODUCT 858169689Skanvoid PhaseIterGVN::verify_step(Node* n) { 859169689Skan if (VerifyIterativeGVN) { 860169689Skan _verify_window[_verify_counter % _verify_window_size] = n; 861169689Skan ++_verify_counter; 862169689Skan ResourceMark rm; 863169689Skan ResourceArea* area = Thread::current()->resource_area(); 864169689Skan VectorSet old_space(area), new_space(area); 865169689Skan if (C->unique() < 1000 || 866169689Skan 0 == _verify_counter % (C->unique() < 10000 ? 10 : 100)) { 867169689Skan ++_verify_full_passes; 868169689Skan Node::verify_recur(C->root(), -1, old_space, new_space); 869169689Skan } 870169689Skan const int verify_depth = 4; 871169689Skan for ( int i = 0; i < _verify_window_size; i++ ) { 872169689Skan Node* n = _verify_window[i]; 873169689Skan if ( n == NULL ) continue; 874169689Skan if( n->in(0) == NodeSentinel ) { // xform_idom 875169689Skan _verify_window[i] = n->in(1); 876169689Skan --i; continue; 877169689Skan } 878169689Skan // Typical fanout is 1-2, so this call visits about 6 nodes. 879169689Skan Node::verify_recur(n, verify_depth, old_space, new_space); 880169689Skan } 881169689Skan } 882169689Skan} 883169689Skan 884169689Skanvoid PhaseIterGVN::trace_PhaseIterGVN(Node* n, Node* nn, const Type* oldtype) { 885169689Skan if (TraceIterativeGVN) { 886169689Skan uint wlsize = _worklist.size(); 887169689Skan const Type* newtype = type_or_null(n); 888169689Skan if (nn != n) { 889169689Skan // print old node 890169689Skan tty->print("< "); 891169689Skan if (oldtype != newtype && oldtype != NULL) { 892169689Skan oldtype->dump(); 893169689Skan } 894169689Skan do { tty->print("\t"); } while (tty->position() < 16); 895169689Skan tty->print("<"); 896169689Skan n->dump(); 897169689Skan } 898169689Skan if (oldtype != newtype || nn != n) { 899169689Skan // print new node and/or new type 900169689Skan if (oldtype == NULL) { 901169689Skan tty->print("* "); 902169689Skan } else if (nn != n) { 903169689Skan tty->print("> "); 904169689Skan } else { 905169689Skan tty->print("= "); 906169689Skan } 907169689Skan if (newtype == NULL) { 908169689Skan tty->print("null"); 909169689Skan } else { 910169689Skan newtype->dump(); 911169689Skan } 912169689Skan do { tty->print("\t"); } while (tty->position() < 16); 913169689Skan nn->dump(); 914169689Skan } 915169689Skan if (Verbose && wlsize < _worklist.size()) { 916169689Skan tty->print(" Push {"); 917169689Skan while (wlsize != _worklist.size()) { 918169689Skan Node* pushed = _worklist.at(wlsize++); 919169689Skan tty->print(" %d", pushed->_idx); 920169689Skan } 921169689Skan tty->print_cr(" }"); 922169689Skan } 923169689Skan if (nn != n) { 924169689Skan // ignore n, it might be subsumed 925169689Skan verify_step((Node*) NULL); 926169689Skan } 927169689Skan } 928169689Skan} 929169689Skan 930169689Skanvoid PhaseIterGVN::init_verifyPhaseIterGVN() { 931169689Skan _verify_counter = 0; 932169689Skan _verify_full_passes = 0; 933169689Skan for (int i = 0; i < _verify_window_size; i++) { 934169689Skan _verify_window[i] = NULL; 935169689Skan } 936169689Skan} 937169689Skan 938169689Skanvoid PhaseIterGVN::verify_PhaseIterGVN() { 939169689Skan C->verify_graph_edges(); 940169689Skan if( VerifyOpto && allow_progress() ) { 941169689Skan // Must turn off allow_progress to enable assert and break recursion 942169689Skan C->root()->verify(); 943169689Skan { // Check if any progress was missed using IterGVN 944169689Skan // Def-Use info enables transformations not attempted in wash-pass 945169689Skan // e.g. Region/Phi cleanup, ... 946169689Skan // Null-check elision -- may not have reached fixpoint 947169689Skan // do not propagate to dominated nodes 948169689Skan ResourceMark rm; 949169689Skan PhaseIterGVN igvn2(this,"Verify"); // Fresh and clean! 950169689Skan // Fill worklist completely 951169689Skan igvn2.init_worklist(C->root()); 952169689Skan 953169689Skan igvn2.set_allow_progress(false); 954169689Skan igvn2.optimize(); 955169689Skan igvn2.set_allow_progress(true); 956169689Skan } 957169689Skan } 958169689Skan if (VerifyIterativeGVN && PrintOpto) { 959169689Skan if (_verify_counter == _verify_full_passes) { 960169689Skan tty->print_cr("VerifyIterativeGVN: %d transforms and verify passes", 961169689Skan (int) _verify_full_passes); 962169689Skan } else { 963169689Skan tty->print_cr("VerifyIterativeGVN: %d transforms, %d full verify passes", 964169689Skan (int) _verify_counter, (int) _verify_full_passes); 965169689Skan } 966169689Skan } 967169689Skan} 968169689Skan#endif /* PRODUCT */ 969169689Skan 970169689Skan#ifdef ASSERT 971169689Skan/** 972169689Skan * Dumps information that can help to debug the problem. A debug 973169689Skan * build fails with an assert. 974169689Skan */ 975169689Skanvoid PhaseIterGVN::dump_infinite_loop_info(Node* n) { 976169689Skan n->dump(4); 977169689Skan _worklist.dump(); 978169689Skan assert(false, "infinite loop in PhaseIterGVN::optimize"); 979169689Skan} 980169689Skan 981169689Skan/** 982169689Skan * Prints out information about IGVN if the 'verbose' option is used. 983169689Skan */ 984169689Skanvoid PhaseIterGVN::trace_PhaseIterGVN_verbose(Node* n, int num_processed) { 985169689Skan if (TraceIterativeGVN && Verbose) { 986169689Skan tty->print(" Pop "); 987169689Skan n->dump(); 988169689Skan if ((num_processed % 100) == 0) { 989169689Skan _worklist.print_set(); 990169689Skan } 991169689Skan } 992169689Skan} 993169689Skan#endif /* ASSERT */ 994169689Skan 995169689Skanvoid PhaseIterGVN::optimize() { 996169689Skan DEBUG_ONLY(uint num_processed = 0;) 997169689Skan NOT_PRODUCT(init_verifyPhaseIterGVN();) 998169689Skan 999169689Skan uint loop_count = 0; 1000169689Skan // Pull from worklist and transform the node. If the node has changed, 1001169689Skan // update edge info and put uses on worklist. 1002169689Skan while(_worklist.size()) { 1003169689Skan if (C->check_node_count(NodeLimitFudgeFactor * 2, "Out of nodes")) { 1004169689Skan return; 1005169689Skan } 1006169689Skan Node* n = _worklist.pop(); 1007169689Skan if (++loop_count >= K * C->live_nodes()) { 1008169689Skan DEBUG_ONLY(dump_infinite_loop_info(n);) 1009169689Skan C->record_method_not_compilable("infinite loop in PhaseIterGVN::optimize"); 1010169689Skan return; 1011169689Skan } 1012169689Skan DEBUG_ONLY(trace_PhaseIterGVN_verbose(n, num_processed++);) 1013169689Skan if (n->outcnt() != 0) { 1014169689Skan NOT_PRODUCT(const Type* oldtype = type_or_null(n)); 1015169689Skan // Do the transformation 1016169689Skan Node* nn = transform_old(n); 1017169689Skan NOT_PRODUCT(trace_PhaseIterGVN(n, nn, oldtype);) 1018169689Skan } else if (!n->is_top()) { 1019169689Skan remove_dead_node(n); 1020169689Skan } 1021169689Skan } 1022169689Skan NOT_PRODUCT(verify_PhaseIterGVN();) 1023169689Skan} 1024169689Skan 1025169689Skan 1026169689Skan/** 1027169689Skan * Register a new node with the optimizer. Update the types array, the def-use 1028169689Skan * info. Put on worklist. 1029169689Skan */ 1030169689SkanNode* PhaseIterGVN::register_new_node_with_optimizer(Node* n, Node* orig) { 1031169689Skan set_type_bottom(n); 1032169689Skan _worklist.push(n); 1033169689Skan if (orig != NULL) C->copy_node_notes_to(n, orig); 1034169689Skan return n; 1035169689Skan} 1036169689Skan 1037169689Skan//------------------------------transform-------------------------------------- 1038169689Skan// Non-recursive: idealize Node 'n' with respect to its inputs and its value 1039169689SkanNode *PhaseIterGVN::transform( Node *n ) { 1040169689Skan if (_delay_transform) { 1041169689Skan // Register the node but don't optimize for now 1042169689Skan register_new_node_with_optimizer(n); 1043169689Skan return n; 1044169689Skan } 1045169689Skan 1046169689Skan // If brand new node, make space in type array, and give it a type. 1047169689Skan ensure_type_or_null(n); 1048169689Skan if (type_or_null(n) == NULL) { 1049169689Skan set_type_bottom(n); 1050169689Skan } 1051169689Skan 1052169689Skan return transform_old(n); 1053169689Skan} 1054169689Skan 1055169689SkanNode *PhaseIterGVN::transform_old(Node* n) { 1056169689Skan DEBUG_ONLY(uint loop_count = 0;); 1057169689Skan NOT_PRODUCT(set_transforms()); 1058169689Skan 1059169689Skan // Remove 'n' from hash table in case it gets modified 1060169689Skan _table.hash_delete(n); 1061169689Skan if (VerifyIterativeGVN) { 1062169689Skan assert(!_table.find_index(n->_idx), "found duplicate entry in table"); 1063169689Skan } 1064169689Skan 1065169689Skan // Apply the Ideal call in a loop until it no longer applies 1066169689Skan Node* k = n; 1067169689Skan DEBUG_ONLY(dead_loop_check(k);) 1068169689Skan DEBUG_ONLY(bool is_new = (k->outcnt() == 0);) 1069169689Skan Node* i = k->Ideal(this, /*can_reshape=*/true); 1070169689Skan assert(i != k || is_new || i->outcnt() > 0, "don't return dead nodes"); 1071169689Skan#ifndef PRODUCT 1072169689Skan verify_step(k); 1073169689Skan if (i && VerifyOpto ) { 1074169689Skan if (!allow_progress()) { 1075169689Skan if (i->is_Add() && (i->outcnt() == 1)) { 1076169689Skan // Switched input to left side because this is the only use 1077169689Skan } else if (i->is_If() && (i->in(0) == NULL)) { 1078169689Skan // This IF is dead because it is dominated by an equivalent IF When 1079169689Skan // dominating if changed, info is not propagated sparsely to 'this' 1080169689Skan // Propagating this info further will spuriously identify other 1081169689Skan // progress. 1082169689Skan return i; 1083169689Skan } else 1084169689Skan set_progress(); 1085169689Skan } else { 1086169689Skan set_progress(); 1087169689Skan } 1088169689Skan } 1089169689Skan#endif 1090169689Skan 1091169689Skan while (i != NULL) { 1092169689Skan#ifndef PRODUCT 1093169689Skan if (loop_count >= K) { 1094169689Skan dump_infinite_loop_info(i); 1095169689Skan } 1096169689Skan loop_count++; 1097169689Skan#endif 1098169689Skan assert((i->_idx >= k->_idx) || i->is_top(), "Idealize should return new nodes, use Identity to return old nodes"); 1099169689Skan // Made a change; put users of original Node on worklist 1100169689Skan add_users_to_worklist(k); 1101169689Skan // Replacing root of transform tree? 1102169689Skan if (k != i) { 1103169689Skan // Make users of old Node now use new. 1104169689Skan subsume_node(k, i); 1105169689Skan k = i; 1106169689Skan } 1107169689Skan DEBUG_ONLY(dead_loop_check(k);) 1108169689Skan // Try idealizing again 1109169689Skan DEBUG_ONLY(is_new = (k->outcnt() == 0);) 1110169689Skan i = k->Ideal(this, /*can_reshape=*/true); 1111169689Skan assert(i != k || is_new || (i->outcnt() > 0), "don't return dead nodes"); 1112169689Skan#ifndef PRODUCT 1113169689Skan verify_step(k); 1114169689Skan if (i && VerifyOpto) { 1115169689Skan set_progress(); 1116169689Skan } 1117169689Skan#endif 1118169689Skan } 1119169689Skan 1120169689Skan // If brand new node, make space in type array. 1121169689Skan ensure_type_or_null(k); 1122169689Skan 1123169689Skan // See what kind of values 'k' takes on at runtime 1124169689Skan const Type* t = k->Value(this); 1125169689Skan assert(t != NULL, "value sanity"); 1126169689Skan 1127169689Skan // Since I just called 'Value' to compute the set of run-time values 1128169689Skan // for this Node, and 'Value' is non-local (and therefore expensive) I'll 1129169689Skan // cache Value. Later requests for the local phase->type of this Node can 1130169689Skan // use the cached Value instead of suffering with 'bottom_type'. 1131169689Skan if (type_or_null(k) != t) { 1132169689Skan#ifndef PRODUCT 1133169689Skan inc_new_values(); 1134169689Skan set_progress(); 1135169689Skan#endif 1136169689Skan set_type(k, t); 1137169689Skan // If k is a TypeNode, capture any more-precise type permanently into Node 1138169689Skan k->raise_bottom_type(t); 1139169689Skan // Move users of node to worklist 1140169689Skan add_users_to_worklist(k); 1141169689Skan } 1142169689Skan // If 'k' computes a constant, replace it with a constant 1143169689Skan if (t->singleton() && !k->is_Con()) { 1144169689Skan NOT_PRODUCT(set_progress();) 1145169689Skan Node* con = makecon(t); // Make a constant 1146169689Skan add_users_to_worklist(k); 1147169689Skan subsume_node(k, con); // Everybody using k now uses con 1148169689Skan return con; 1149169689Skan } 1150169689Skan 1151169689Skan // Now check for Identities 1152169689Skan i = k->Identity(this); // Look for a nearby replacement 1153169689Skan if (i != k) { // Found? Return replacement! 1154169689Skan NOT_PRODUCT(set_progress();) 1155169689Skan add_users_to_worklist(k); 1156169689Skan subsume_node(k, i); // Everybody using k now uses i 1157169689Skan return i; 1158169689Skan } 1159169689Skan 1160169689Skan // Global Value Numbering 1161169689Skan i = hash_find_insert(k); // Check for pre-existing node 1162169689Skan if (i && (i != k)) { 1163169689Skan // Return the pre-existing node if it isn't dead 1164169689Skan NOT_PRODUCT(set_progress();) 1165169689Skan add_users_to_worklist(k); 1166169689Skan subsume_node(k, i); // Everybody using k now uses i 1167169689Skan return i; 1168169689Skan } 1169169689Skan 1170169689Skan // Return Idealized original 1171169689Skan return k; 1172169689Skan} 1173169689Skan 1174169689Skan//---------------------------------saturate------------------------------------ 1175169689Skanconst Type* PhaseIterGVN::saturate(const Type* new_type, const Type* old_type, 1176169689Skan const Type* limit_type) const { 1177169689Skan return new_type->narrow(old_type); 1178169689Skan} 1179169689Skan 1180169689Skan//------------------------------remove_globally_dead_node---------------------- 1181169689Skan// Kill a globally dead Node. All uses are also globally dead and are 1182169689Skan// aggressively trimmed. 1183169689Skanvoid PhaseIterGVN::remove_globally_dead_node( Node *dead ) { 1184169689Skan enum DeleteProgress { 1185169689Skan PROCESS_INPUTS, 1186169689Skan PROCESS_OUTPUTS 1187169689Skan }; 1188169689Skan assert(_stack.is_empty(), "not empty"); 1189169689Skan _stack.push(dead, PROCESS_INPUTS); 1190169689Skan 1191169689Skan while (_stack.is_nonempty()) { 1192169689Skan dead = _stack.node(); 1193169689Skan uint progress_state = _stack.index(); 1194169689Skan assert(dead != C->root(), "killing root, eh?"); 1195169689Skan assert(!dead->is_top(), "add check for top when pushing"); 1196169689Skan NOT_PRODUCT( set_progress(); ) 1197169689Skan if (progress_state == PROCESS_INPUTS) { 1198169689Skan // After following inputs, continue to outputs 1199169689Skan _stack.set_index(PROCESS_OUTPUTS); 1200169689Skan if (!dead->is_Con()) { // Don't kill cons but uses 1201169689Skan bool recurse = false; 1202169689Skan // Remove from hash table 1203169689Skan _table.hash_delete( dead ); 1204169689Skan // Smash all inputs to 'dead', isolating him completely 1205169689Skan for (uint i = 0; i < dead->req(); i++) { 1206169689Skan Node *in = dead->in(i); 1207169689Skan if (in != NULL && in != C->top()) { // Points to something? 1208169689Skan int nrep = dead->replace_edge(in, NULL); // Kill edges 1209169689Skan assert((nrep > 0), "sanity"); 1210169689Skan if (in->outcnt() == 0) { // Made input go dead? 1211169689Skan _stack.push(in, PROCESS_INPUTS); // Recursively remove 1212169689Skan recurse = true; 1213169689Skan } else if (in->outcnt() == 1 && 1214169689Skan in->has_special_unique_user()) { 1215169689Skan _worklist.push(in->unique_out()); 1216169689Skan } else if (in->outcnt() <= 2 && dead->is_Phi()) { 1217169689Skan if (in->Opcode() == Op_Region) { 1218169689Skan _worklist.push(in); 1219169689Skan } else if (in->is_Store()) { 1220169689Skan DUIterator_Fast imax, i = in->fast_outs(imax); 1221169689Skan _worklist.push(in->fast_out(i)); 1222169689Skan i++; 1223169689Skan if (in->outcnt() == 2) { 1224169689Skan _worklist.push(in->fast_out(i)); 1225169689Skan i++; 1226169689Skan } 1227169689Skan assert(!(i < imax), "sanity"); 1228169689Skan } 1229169689Skan } 1230169689Skan if (ReduceFieldZeroing && dead->is_Load() && i == MemNode::Memory && 1231169689Skan in->is_Proj() && in->in(0) != NULL && in->in(0)->is_Initialize()) { 1232169689Skan // A Load that directly follows an InitializeNode is 1233169689Skan // going away. The Stores that follow are candidates 1234169689Skan // again to be captured by the InitializeNode. 1235169689Skan for (DUIterator_Fast jmax, j = in->fast_outs(jmax); j < jmax; j++) { 1236169689Skan Node *n = in->fast_out(j); 1237169689Skan if (n->is_Store()) { 1238169689Skan _worklist.push(n); 1239169689Skan } 1240169689Skan } 1241169689Skan } 1242169689Skan } // if (in != NULL && in != C->top()) 1243169689Skan } // for (uint i = 0; i < dead->req(); i++) 1244169689Skan if (recurse) { 1245169689Skan continue; 1246169689Skan } 1247169689Skan } // if (!dead->is_Con()) 1248169689Skan } // if (progress_state == PROCESS_INPUTS) 1249169689Skan 1250169689Skan // Aggressively kill globally dead uses 1251169689Skan // (Rather than pushing all the outs at once, we push one at a time, 1252169689Skan // plus the parent to resume later, because of the indefinite number 1253169689Skan // of edge deletions per loop trip.) 1254169689Skan if (dead->outcnt() > 0) { 1255169689Skan // Recursively remove output edges 1256169689Skan _stack.push(dead->raw_out(0), PROCESS_INPUTS); 1257169689Skan } else { 1258169689Skan // Finished disconnecting all input and output edges. 1259169689Skan _stack.pop(); 1260169689Skan // Remove dead node from iterative worklist 1261169689Skan _worklist.remove(dead); 1262169689Skan // Constant node that has no out-edges and has only one in-edge from 1263169689Skan // root is usually dead. However, sometimes reshaping walk makes 1264169689Skan // it reachable by adding use edges. So, we will NOT count Con nodes 1265169689Skan // as dead to be conservative about the dead node count at any 1266169689Skan // given time. 1267169689Skan if (!dead->is_Con()) { 1268169689Skan C->record_dead_node(dead->_idx); 1269169689Skan } 1270169689Skan if (dead->is_macro()) { 1271169689Skan C->remove_macro_node(dead); 1272169689Skan } 1273169689Skan if (dead->is_expensive()) { 1274169689Skan C->remove_expensive_node(dead); 1275169689Skan } 1276169689Skan } 1277169689Skan } // while (_stack.is_nonempty()) 1278169689Skan} 1279169689Skan 1280169689Skan//------------------------------subsume_node----------------------------------- 1281169689Skan// Remove users from node 'old' and add them to node 'nn'. 1282169689Skanvoid PhaseIterGVN::subsume_node( Node *old, Node *nn ) { 1283169689Skan assert( old != hash_find(old), "should already been removed" ); 1284169689Skan assert( old != C->top(), "cannot subsume top node"); 1285169689Skan // Copy debug or profile information to the new version: 1286169689Skan C->copy_node_notes_to(nn, old); 1287169689Skan // Move users of node 'old' to node 'nn' 1288169689Skan for (DUIterator_Last imin, i = old->last_outs(imin); i >= imin; ) { 1289169689Skan Node* use = old->last_out(i); // for each use... 1290169689Skan // use might need re-hashing (but it won't if it's a new node) 1291169689Skan bool is_in_table = _table.hash_delete( use ); 1292169689Skan // Update use-def info as well 1293169689Skan // We remove all occurrences of old within use->in, 1294169689Skan // so as to avoid rehashing any node more than once. 1295169689Skan // The hash table probe swamps any outer loop overhead. 1296169689Skan uint num_edges = 0; 1297169689Skan for (uint jmax = use->len(), j = 0; j < jmax; j++) { 1298169689Skan if (use->in(j) == old) { 1299169689Skan use->set_req(j, nn); 1300169689Skan ++num_edges; 1301169689Skan } 1302169689Skan } 1303169689Skan // Insert into GVN hash table if unique 1304169689Skan // If a duplicate, 'use' will be cleaned up when pulled off worklist 1305169689Skan if( is_in_table ) { 1306169689Skan hash_find_insert(use); 1307169689Skan } 1308169689Skan i -= num_edges; // we deleted 1 or more copies of this edge 1309169689Skan } 1310169689Skan 1311169689Skan // Smash all inputs to 'old', isolating him completely 1312169689Skan Node *temp = new (C) Node(1); 1313169689Skan temp->init_req(0,nn); // Add a use to nn to prevent him from dying 1314169689Skan remove_dead_node( old ); 1315169689Skan temp->del_req(0); // Yank bogus edge 1316169689Skan#ifndef PRODUCT 1317169689Skan if( VerifyIterativeGVN ) { 1318169689Skan for ( int i = 0; i < _verify_window_size; i++ ) { 1319169689Skan if ( _verify_window[i] == old ) 1320169689Skan _verify_window[i] = nn; 1321169689Skan } 1322169689Skan } 1323169689Skan#endif 1324169689Skan _worklist.remove(temp); // this can be necessary 1325169689Skan temp->destruct(); // reuse the _idx of this little guy 1326169689Skan} 1327169689Skan 1328169689Skan//------------------------------add_users_to_worklist-------------------------- 1329169689Skanvoid PhaseIterGVN::add_users_to_worklist0( Node *n ) { 1330169689Skan for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1331169689Skan _worklist.push(n->fast_out(i)); // Push on worklist 1332169689Skan } 1333169689Skan} 1334169689Skan 1335169689Skanvoid PhaseIterGVN::add_users_to_worklist( Node *n ) { 1336169689Skan add_users_to_worklist0(n); 1337169689Skan 1338169689Skan // Move users of node to worklist 1339169689Skan for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1340169689Skan Node* use = n->fast_out(i); // Get use 1341169689Skan 1342169689Skan if( use->is_Multi() || // Multi-definer? Push projs on worklist 1343169689Skan use->is_Store() ) // Enable store/load same address 1344169689Skan add_users_to_worklist0(use); 1345169689Skan 1346169689Skan // If we changed the receiver type to a call, we need to revisit 1347169689Skan // the Catch following the call. It's looking for a non-NULL 1348169689Skan // receiver to know when to enable the regular fall-through path 1349169689Skan // in addition to the NullPtrException path. 1350169689Skan if (use->is_CallDynamicJava() && n == use->in(TypeFunc::Parms)) { 1351169689Skan Node* p = use->as_CallDynamicJava()->proj_out(TypeFunc::Control); 1352169689Skan if (p != NULL) { 1353169689Skan add_users_to_worklist0(p); 1354169689Skan } 1355169689Skan } 1356169689Skan 1357169689Skan if( use->is_Cmp() ) { // Enable CMP/BOOL optimization 1358169689Skan add_users_to_worklist(use); // Put Bool on worklist 1359169689Skan // Look for the 'is_x2logic' pattern: "x ? : 0 : 1" and put the 1360169689Skan // phi merging either 0 or 1 onto the worklist 1361169689Skan if (use->outcnt() > 0) { 1362169689Skan Node* bol = use->raw_out(0); 1363169689Skan if (bol->outcnt() > 0) { 1364169689Skan Node* iff = bol->raw_out(0); 1365169689Skan if (iff->outcnt() == 2) { 1366169689Skan Node* ifproj0 = iff->raw_out(0); 1367169689Skan Node* ifproj1 = iff->raw_out(1); 1368169689Skan if (ifproj0->outcnt() > 0 && ifproj1->outcnt() > 0) { 1369169689Skan Node* region0 = ifproj0->raw_out(0); 1370169689Skan Node* region1 = ifproj1->raw_out(0); 1371169689Skan if( region0 == region1 ) 1372169689Skan add_users_to_worklist0(region0); 1373169689Skan } 1374169689Skan } 1375169689Skan } 1376169689Skan } 1377169689Skan } 1378169689Skan 1379169689Skan uint use_op = use->Opcode(); 1380169689Skan // If changed Cast input, check Phi users for simple cycles 1381169689Skan if( use->is_ConstraintCast() || use->is_CheckCastPP() ) { 1382169689Skan for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) { 1383169689Skan Node* u = use->fast_out(i2); 1384169689Skan if (u->is_Phi()) 1385169689Skan _worklist.push(u); 1386169689Skan } 1387169689Skan } 1388169689Skan // If changed LShift inputs, check RShift users for useless sign-ext 1389169689Skan if( use_op == Op_LShiftI ) { 1390169689Skan for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) { 1391169689Skan Node* u = use->fast_out(i2); 1392169689Skan if (u->Opcode() == Op_RShiftI) 1393169689Skan _worklist.push(u); 1394169689Skan } 1395169689Skan } 1396169689Skan // If changed AddP inputs, check Stores for loop invariant 1397169689Skan if( use_op == Op_AddP ) { 1398169689Skan for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) { 1399169689Skan Node* u = use->fast_out(i2); 1400169689Skan if (u->is_Mem()) 1401169689Skan _worklist.push(u); 1402169689Skan } 1403169689Skan } 1404169689Skan // If changed initialization activity, check dependent Stores 1405169689Skan if (use_op == Op_Allocate || use_op == Op_AllocateArray) { 1406169689Skan InitializeNode* init = use->as_Allocate()->initialization(); 1407169689Skan if (init != NULL) { 1408169689Skan Node* imem = init->proj_out(TypeFunc::Memory); 1409169689Skan if (imem != NULL) add_users_to_worklist0(imem); 1410169689Skan } 1411169689Skan } 1412169689Skan if (use_op == Op_Initialize) { 1413169689Skan Node* imem = use->as_Initialize()->proj_out(TypeFunc::Memory); 1414169689Skan if (imem != NULL) add_users_to_worklist0(imem); 1415169689Skan } 1416169689Skan } 1417169689Skan} 1418169689Skan 1419169689Skan/** 1420169689Skan * Remove the speculative part of all types that we know of 1421169689Skan */ 1422169689Skanvoid PhaseIterGVN::remove_speculative_types() { 1423169689Skan assert(UseTypeSpeculation, "speculation is off"); 1424169689Skan for (uint i = 0; i < _types.Size(); i++) { 1425169689Skan const Type* t = _types.fast_lookup(i); 1426169689Skan if (t != NULL) { 1427169689Skan _types.map(i, t->remove_speculative()); 1428169689Skan } 1429169689Skan } 1430169689Skan _table.check_no_speculative_types(); 1431169689Skan} 1432169689Skan 1433169689Skan//============================================================================= 1434169689Skan#ifndef PRODUCT 1435169689Skanuint PhaseCCP::_total_invokes = 0; 1436169689Skanuint PhaseCCP::_total_constants = 0; 1437169689Skan#endif 1438169689Skan//------------------------------PhaseCCP--------------------------------------- 1439169689Skan// Conditional Constant Propagation, ala Wegman & Zadeck 1440169689SkanPhaseCCP::PhaseCCP( PhaseIterGVN *igvn ) : PhaseIterGVN(igvn) { 1441169689Skan NOT_PRODUCT( clear_constants(); ) 1442169689Skan assert( _worklist.size() == 0, "" ); 1443169689Skan // Clear out _nodes from IterGVN. Must be clear to transform call. 1444169689Skan _nodes.clear(); // Clear out from IterGVN 1445169689Skan analyze(); 1446169689Skan} 1447169689Skan 1448169689Skan#ifndef PRODUCT 1449169689Skan//------------------------------~PhaseCCP-------------------------------------- 1450169689SkanPhaseCCP::~PhaseCCP() { 1451169689Skan inc_invokes(); 1452169689Skan _total_constants += count_constants(); 1453169689Skan} 1454169689Skan#endif 1455169689Skan 1456169689Skan 1457169689Skan#ifdef ASSERT 1458169689Skanstatic bool ccp_type_widens(const Type* t, const Type* t0) { 1459169689Skan assert(t->meet(t0) == t, "Not monotonic"); 1460169689Skan switch (t->base() == t0->base() ? t->base() : Type::Top) { 1461169689Skan case Type::Int: 1462169689Skan assert(t0->isa_int()->_widen <= t->isa_int()->_widen, "widen increases"); 1463169689Skan break; 1464169689Skan case Type::Long: 1465169689Skan assert(t0->isa_long()->_widen <= t->isa_long()->_widen, "widen increases"); 1466169689Skan break; 1467169689Skan } 1468169689Skan return true; 1469169689Skan} 1470169689Skan#endif //ASSERT 1471169689Skan 1472169689Skan//------------------------------analyze---------------------------------------- 1473169689Skanvoid PhaseCCP::analyze() { 1474169689Skan // Initialize all types to TOP, optimistic analysis 1475169689Skan for (int i = C->unique() - 1; i >= 0; i--) { 1476169689Skan _types.map(i,Type::TOP); 1477169689Skan } 1478169689Skan 1479169689Skan // Push root onto worklist 1480169689Skan Unique_Node_List worklist; 1481169689Skan worklist.push(C->root()); 1482169689Skan 1483169689Skan // Pull from worklist; compute new value; push changes out. 1484169689Skan // This loop is the meat of CCP. 1485169689Skan while( worklist.size() ) { 1486169689Skan Node *n = worklist.pop(); 1487169689Skan const Type *t = n->Value(this); 1488169689Skan if (t != type(n)) { 1489169689Skan assert(ccp_type_widens(t, type(n)), "ccp type must widen"); 1490169689Skan#ifndef PRODUCT 1491169689Skan if( TracePhaseCCP ) { 1492169689Skan t->dump(); 1493169689Skan do { tty->print("\t"); } while (tty->position() < 16); 1494169689Skan n->dump(); 1495169689Skan } 1496169689Skan#endif 1497169689Skan set_type(n, t); 1498169689Skan for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { 1499169689Skan Node* m = n->fast_out(i); // Get user 1500169689Skan if( m->is_Region() ) { // New path to Region? Must recheck Phis too 1501169689Skan for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) { 1502169689Skan Node* p = m->fast_out(i2); // Propagate changes to uses 1503169689Skan if( p->bottom_type() != type(p) ) // If not already bottomed out 1504169689Skan worklist.push(p); // Propagate change to user 1505169689Skan } 1506169689Skan } 1507169689Skan // If we changed the receiver type to a call, we need to revisit 1508169689Skan // the Catch following the call. It's looking for a non-NULL 1509169689Skan // receiver to know when to enable the regular fall-through path 1510169689Skan // in addition to the NullPtrException path 1511169689Skan if (m->is_Call()) { 1512169689Skan for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) { 1513169689Skan Node* p = m->fast_out(i2); // Propagate changes to uses 1514169689Skan if (p->is_Proj() && p->as_Proj()->_con == TypeFunc::Control && p->outcnt() == 1) 1515169689Skan worklist.push(p->unique_out()); 1516169689Skan } 1517169689Skan } 1518169689Skan if( m->bottom_type() != type(m) ) // If not already bottomed out 1519169689Skan worklist.push(m); // Propagate change to user 1520169689Skan } 1521169689Skan } 1522169689Skan } 1523169689Skan} 1524169689Skan 1525169689Skan//------------------------------do_transform----------------------------------- 1526169689Skan// Top level driver for the recursive transformer 1527169689Skanvoid PhaseCCP::do_transform() { 1528169689Skan // Correct leaves of new-space Nodes; they point to old-space. 1529169689Skan C->set_root( transform(C->root())->as_Root() ); 1530169689Skan assert( C->top(), "missing TOP node" ); 1531169689Skan assert( C->root(), "missing root" ); 1532169689Skan 1533169689Skan // Eagerly remove castPP nodes here. CastPP nodes might not be 1534169689Skan // removed in the subsequent IGVN phase if a node that changes 1535169689Skan // in(1) of a castPP is processed prior to the castPP node. 1536169689Skan for (uint i = 0; i < _worklist.size(); i++) { 1537169689Skan Node* n = _worklist.at(i); 1538169689Skan 1539169689Skan if (n->is_ConstraintCast()) { 1540169689Skan Node* nn = n->Identity(this); 1541169689Skan if (nn != n) { 1542169689Skan replace_node(n, nn); 1543169689Skan --i; 1544169689Skan } 1545169689Skan } 1546169689Skan } 1547169689Skan} 1548169689Skan 1549169689Skan//------------------------------transform-------------------------------------- 1550169689Skan// Given a Node in old-space, clone him into new-space. 1551169689Skan// Convert any of his old-space children into new-space children. 1552169689SkanNode *PhaseCCP::transform( Node *n ) { 1553169689Skan Node *new_node = _nodes[n->_idx]; // Check for transformed node 1554169689Skan if( new_node != NULL ) 1555169689Skan return new_node; // Been there, done that, return old answer 1556169689Skan new_node = transform_once(n); // Check for constant 1557169689Skan _nodes.map( n->_idx, new_node ); // Flag as having been cloned 1558169689Skan 1559169689Skan // Allocate stack of size _nodes.Size()/2 to avoid frequent realloc 1560169689Skan GrowableArray <Node *> trstack(C->unique() >> 1); 1561169689Skan 1562169689Skan trstack.push(new_node); // Process children of cloned node 1563169689Skan while ( trstack.is_nonempty() ) { 1564169689Skan Node *clone = trstack.pop(); 1565169689Skan uint cnt = clone->req(); 1566169689Skan for( uint i = 0; i < cnt; i++ ) { // For all inputs do 1567169689Skan Node *input = clone->in(i); 1568169689Skan if( input != NULL ) { // Ignore NULLs 1569169689Skan Node *new_input = _nodes[input->_idx]; // Check for cloned input node 1570169689Skan if( new_input == NULL ) { 1571169689Skan new_input = transform_once(input); // Check for constant 1572169689Skan _nodes.map( input->_idx, new_input );// Flag as having been cloned 1573169689Skan trstack.push(new_input); 1574169689Skan } 1575169689Skan assert( new_input == clone->in(i), "insanity check"); 1576169689Skan } 1577169689Skan } 1578169689Skan } 1579169689Skan return new_node; 1580169689Skan} 1581169689Skan 1582169689Skan 1583169689Skan//------------------------------transform_once--------------------------------- 1584169689Skan// For PhaseCCP, transformation is IDENTITY unless Node computed a constant. 1585169689SkanNode *PhaseCCP::transform_once( Node *n ) { 1586169689Skan const Type *t = type(n); 1587169689Skan // Constant? Use constant Node instead 1588169689Skan if( t->singleton() ) { 1589169689Skan Node *nn = n; // Default is to return the original constant 1590169689Skan if( t == Type::TOP ) { 1591169689Skan // cache my top node on the Compile instance 1592169689Skan if( C->cached_top_node() == NULL || C->cached_top_node()->in(0) == NULL ) { 1593169689Skan C->set_cached_top_node( ConNode::make(C, Type::TOP) ); 1594169689Skan set_type(C->top(), Type::TOP); 1595169689Skan } 1596169689Skan nn = C->top(); 1597169689Skan } 1598169689Skan if( !n->is_Con() ) { 1599169689Skan if( t != Type::TOP ) { 1600169689Skan nn = makecon(t); // ConNode::make(t); 1601169689Skan NOT_PRODUCT( inc_constants(); ) 1602169689Skan } else if( n->is_Region() ) { // Unreachable region 1603169689Skan // Note: nn == C->top() 1604169689Skan n->set_req(0, NULL); // Cut selfreference 1605169689Skan // Eagerly remove dead phis to avoid phis copies creation. 1606169689Skan for (DUIterator i = n->outs(); n->has_out(i); i++) { 1607169689Skan Node* m = n->out(i); 1608169689Skan if( m->is_Phi() ) { 1609169689Skan assert(type(m) == Type::TOP, "Unreachable region should not have live phis."); 1610169689Skan replace_node(m, nn); 1611169689Skan --i; // deleted this phi; rescan starting with next position 1612169689Skan } 1613169689Skan } 1614169689Skan } 1615169689Skan replace_node(n,nn); // Update DefUse edges for new constant 1616169689Skan } 1617169689Skan return nn; 1618169689Skan } 1619169689Skan 1620169689Skan // If x is a TypeNode, capture any more-precise type permanently into Node 1621169689Skan if (t != n->bottom_type()) { 1622169689Skan hash_delete(n); // changing bottom type may force a rehash 1623169689Skan n->raise_bottom_type(t); 1624169689Skan _worklist.push(n); // n re-enters the hash table via the worklist 1625169689Skan } 1626169689Skan 1627169689Skan // Idealize graph using DU info. Must clone() into new-space. 1628169689Skan // DU info is generally used to show profitability, progress or safety 1629169689Skan // (but generally not needed for correctness). 1630169689Skan Node *nn = n->Ideal_DU_postCCP(this); 1631169689Skan 1632169689Skan // TEMPORARY fix to ensure that 2nd GVN pass eliminates NULL checks 1633169689Skan switch( n->Opcode() ) { 1634169689Skan case Op_FastLock: // Revisit FastLocks for lock coarsening 1635169689Skan case Op_If: 1636169689Skan case Op_CountedLoopEnd: 1637169689Skan case Op_Region: 1638169689Skan case Op_Loop: 1639169689Skan case Op_CountedLoop: 1640169689Skan case Op_Conv2B: 1641169689Skan case Op_Opaque1: 1642169689Skan case Op_Opaque2: 1643169689Skan _worklist.push(n); 1644169689Skan break; 1645169689Skan default: 1646169689Skan break; 1647169689Skan } 1648169689Skan if( nn ) { 1649169689Skan _worklist.push(n); 1650169689Skan // Put users of 'n' onto worklist for second igvn transform 1651169689Skan add_users_to_worklist(n); 1652169689Skan return nn; 1653169689Skan } 1654169689Skan 1655169689Skan return n; 1656169689Skan} 1657169689Skan 1658169689Skan//---------------------------------saturate------------------------------------ 1659169689Skanconst Type* PhaseCCP::saturate(const Type* new_type, const Type* old_type, 1660169689Skan const Type* limit_type) const { 1661169689Skan const Type* wide_type = new_type->widen(old_type, limit_type); 1662169689Skan if (wide_type != new_type) { // did we widen? 1663169689Skan // If so, we may have widened beyond the limit type. Clip it back down. 1664169689Skan new_type = wide_type->filter(limit_type); 1665169689Skan } 1666169689Skan return new_type; 1667169689Skan} 1668169689Skan 1669169689Skan//------------------------------print_statistics------------------------------- 1670169689Skan#ifndef PRODUCT 1671169689Skanvoid PhaseCCP::print_statistics() { 1672169689Skan tty->print_cr("CCP: %d constants found: %d", _total_invokes, _total_constants); 1673169689Skan} 1674169689Skan#endif 1675169689Skan 1676169689Skan 1677169689Skan//============================================================================= 1678169689Skan#ifndef PRODUCT 1679169689Skanuint PhasePeephole::_total_peepholes = 0; 1680169689Skan#endif 1681169689Skan//------------------------------PhasePeephole---------------------------------- 1682169689Skan// Conditional Constant Propagation, ala Wegman & Zadeck 1683169689SkanPhasePeephole::PhasePeephole( PhaseRegAlloc *regalloc, PhaseCFG &cfg ) 1684169689Skan : PhaseTransform(Peephole), _regalloc(regalloc), _cfg(cfg) { 1685169689Skan NOT_PRODUCT( clear_peepholes(); ) 1686169689Skan} 1687169689Skan 1688169689Skan#ifndef PRODUCT 1689169689Skan//------------------------------~PhasePeephole--------------------------------- 1690169689SkanPhasePeephole::~PhasePeephole() { 1691169689Skan _total_peepholes += count_peepholes(); 1692169689Skan} 1693169689Skan#endif 1694169689Skan 1695169689Skan//------------------------------transform-------------------------------------- 1696169689SkanNode *PhasePeephole::transform( Node *n ) { 1697169689Skan ShouldNotCallThis(); 1698169689Skan return NULL; 1699169689Skan} 1700169689Skan 1701169689Skan//------------------------------do_transform----------------------------------- 1702169689Skanvoid PhasePeephole::do_transform() { 1703169689Skan bool method_name_not_printed = true; 1704169689Skan 1705169689Skan // Examine each basic block 1706169689Skan for (uint block_number = 1; block_number < _cfg.number_of_blocks(); ++block_number) { 1707169689Skan Block* block = _cfg.get_block(block_number); 1708169689Skan bool block_not_printed = true; 1709169689Skan 1710169689Skan // and each instruction within a block 1711169689Skan uint end_index = block->number_of_nodes(); 1712169689Skan // block->end_idx() not valid after PhaseRegAlloc 1713169689Skan for( uint instruction_index = 1; instruction_index < end_index; ++instruction_index ) { 1714169689Skan Node *n = block->get_node(instruction_index); 1715169689Skan if( n->is_Mach() ) { 1716169689Skan MachNode *m = n->as_Mach(); 1717169689Skan int deleted_count = 0; 1718169689Skan // check for peephole opportunities 1719169689Skan MachNode *m2 = m->peephole( block, instruction_index, _regalloc, deleted_count, C ); 1720169689Skan if( m2 != NULL ) { 1721169689Skan#ifndef PRODUCT 1722169689Skan if( PrintOptoPeephole ) { 1723169689Skan // Print method, first time only 1724169689Skan if( C->method() && method_name_not_printed ) { 1725169689Skan C->method()->print_short_name(); tty->cr(); 1726169689Skan method_name_not_printed = false; 1727169689Skan } 1728169689Skan // Print this block 1729169689Skan if( Verbose && block_not_printed) { 1730169689Skan tty->print_cr("in block"); 1731169689Skan block->dump(); 1732169689Skan block_not_printed = false; 1733169689Skan } 1734169689Skan // Print instructions being deleted 1735169689Skan for( int i = (deleted_count - 1); i >= 0; --i ) { 1736169689Skan block->get_node(instruction_index-i)->as_Mach()->format(_regalloc); tty->cr(); 1737169689Skan } 1738169689Skan tty->print_cr("replaced with"); 1739169689Skan // Print new instruction 1740169689Skan m2->format(_regalloc); 1741169689Skan tty->print("\n\n"); 1742169689Skan } 1743169689Skan#endif 1744169689Skan // Remove old nodes from basic block and update instruction_index 1745169689Skan // (old nodes still exist and may have edges pointing to them 1746169689Skan // as register allocation info is stored in the allocator using 1747169689Skan // the node index to live range mappings.) 1748169689Skan uint safe_instruction_index = (instruction_index - deleted_count); 1749169689Skan for( ; (instruction_index > safe_instruction_index); --instruction_index ) { 1750169689Skan block->remove_node( instruction_index ); 1751169689Skan } 1752169689Skan // install new node after safe_instruction_index 1753169689Skan block->insert_node(m2, safe_instruction_index + 1); 1754169689Skan end_index = block->number_of_nodes() - 1; // Recompute new block size 1755169689Skan NOT_PRODUCT( inc_peepholes(); ) 1756169689Skan } 1757169689Skan } 1758169689Skan } 1759169689Skan } 1760169689Skan} 1761169689Skan 1762169689Skan//------------------------------print_statistics------------------------------- 1763169689Skan#ifndef PRODUCT 1764169689Skanvoid PhasePeephole::print_statistics() { 1765169689Skan tty->print_cr("Peephole: peephole rules applied: %d", _total_peepholes); 1766169689Skan} 1767169689Skan#endif 1768169689Skan 1769169689Skan 1770169689Skan//============================================================================= 1771169689Skan//------------------------------set_req_X-------------------------------------- 1772169689Skanvoid Node::set_req_X( uint i, Node *n, PhaseIterGVN *igvn ) { 1773169689Skan assert( is_not_dead(n), "can not use dead node"); 1774169689Skan assert( igvn->hash_find(this) != this, "Need to remove from hash before changing edges" ); 1775169689Skan Node *old = in(i); 1776169689Skan set_req(i, n); 1777169689Skan 1778169689Skan // old goes dead? 1779169689Skan if( old ) { 1780169689Skan switch (old->outcnt()) { 1781169689Skan case 0: 1782169689Skan // Put into the worklist to kill later. We do not kill it now because the 1783169689Skan // recursive kill will delete the current node (this) if dead-loop exists 1784169689Skan if (!old->is_top()) 1785169689Skan igvn->_worklist.push( old ); 1786169689Skan break; 1787169689Skan case 1: 1788169689Skan if( old->is_Store() || old->has_special_unique_user() ) 1789169689Skan igvn->add_users_to_worklist( old ); 1790169689Skan break; 1791169689Skan case 2: 1792169689Skan if( old->is_Store() ) 1793169689Skan igvn->add_users_to_worklist( old ); 1794169689Skan if( old->Opcode() == Op_Region ) 1795169689Skan igvn->_worklist.push(old); 1796169689Skan break; 1797169689Skan case 3: 1798169689Skan if( old->Opcode() == Op_Region ) { 1799169689Skan igvn->_worklist.push(old); 1800169689Skan igvn->add_users_to_worklist( old ); 1801169689Skan } 1802169689Skan break; 1803169689Skan default: 1804169689Skan break; 1805169689Skan } 1806169689Skan } 1807169689Skan 1808169689Skan} 1809169689Skan 1810169689Skan//-------------------------------replace_by----------------------------------- 1811169689Skan// Using def-use info, replace one node for another. Follow the def-use info 1812169689Skan// to all users of the OLD node. Then make all uses point to the NEW node. 1813169689Skanvoid Node::replace_by(Node *new_node) { 1814169689Skan assert(!is_top(), "top node has no DU info"); 1815169689Skan for (DUIterator_Last imin, i = last_outs(imin); i >= imin; ) { 1816169689Skan Node* use = last_out(i); 1817169689Skan uint uses_found = 0; 1818169689Skan for (uint j = 0; j < use->len(); j++) { 1819169689Skan if (use->in(j) == this) { 1820169689Skan if (j < use->req()) 1821169689Skan use->set_req(j, new_node); 1822169689Skan else use->set_prec(j, new_node); 1823169689Skan uses_found++; 1824169689Skan } 1825169689Skan } 1826169689Skan i -= uses_found; // we deleted 1 or more copies of this edge 1827169689Skan } 1828169689Skan} 1829169689Skan 1830169689Skan//============================================================================= 1831169689Skan//----------------------------------------------------------------------------- 1832169689Skanvoid Type_Array::grow( uint i ) { 1833169689Skan if( !_max ) { 1834169689Skan _max = 1; 1835169689Skan _types = (const Type**)_a->Amalloc( _max * sizeof(Type*) ); 1836169689Skan _types[0] = NULL; 1837169689Skan } 1838169689Skan uint old = _max; 1839169689Skan while( i >= _max ) _max <<= 1; // Double to fit 1840169689Skan _types = (const Type**)_a->Arealloc( _types, old*sizeof(Type*),_max*sizeof(Type*)); 1841169689Skan memset( &_types[old], 0, (_max-old)*sizeof(Type*) ); 1842169689Skan} 1843169689Skan 1844169689Skan//------------------------------dump------------------------------------------- 1845169689Skan#ifndef PRODUCT 1846169689Skanvoid Type_Array::dump() const { 1847169689Skan uint max = Size(); 1848169689Skan for( uint i = 0; i < max; i++ ) { 1849169689Skan if( _types[i] != NULL ) { 1850169689Skan tty->print(" %d\t== ", i); _types[i]->dump(); tty->cr(); 1851169689Skan } 1852169689Skan } 1853169689Skan} 1854169689Skan#endif 1855169689Skan