src/share/vm/opto/phaseX.cpp

Mon, 24 Sep 2018 17:18:38 -0400

author
gromero
date
Mon, 24 Sep 2018 17:18:38 -0400
changeset 9496
bcccbecdde63
parent 9013
18366fa39fe0
child 9041
95a08233f46c
child 9952
19056c781208
permissions
-rw-r--r--

8131048: ppc implement CRC32 intrinsic
Reviewed-by: goetz

duke@435 1 /*
shshahma@8893 2 * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
duke@435 22 *
duke@435 23 */
duke@435 24
stefank@2314 25 #include "precompiled.hpp"
stefank@2314 26 #include "memory/allocation.inline.hpp"
stefank@2314 27 #include "opto/block.hpp"
stefank@2314 28 #include "opto/callnode.hpp"
stefank@2314 29 #include "opto/cfgnode.hpp"
stefank@2314 30 #include "opto/connode.hpp"
stefank@2314 31 #include "opto/idealGraphPrinter.hpp"
stefank@2314 32 #include "opto/loopnode.hpp"
stefank@2314 33 #include "opto/machnode.hpp"
stefank@2314 34 #include "opto/opcodes.hpp"
stefank@2314 35 #include "opto/phaseX.hpp"
stefank@2314 36 #include "opto/regalloc.hpp"
stefank@2314 37 #include "opto/rootnode.hpp"
duke@435 38
duke@435 39 //=============================================================================
duke@435 40 #define NODE_HASH_MINIMUM_SIZE 255
duke@435 41 //------------------------------NodeHash---------------------------------------
duke@435 42 NodeHash::NodeHash(uint est_max_size) :
duke@435 43 _max( round_up(est_max_size < NODE_HASH_MINIMUM_SIZE ? NODE_HASH_MINIMUM_SIZE : est_max_size) ),
duke@435 44 _a(Thread::current()->resource_area()),
duke@435 45 _table( NEW_ARENA_ARRAY( _a , Node* , _max ) ), // (Node**)_a->Amalloc(_max * sizeof(Node*)) ),
duke@435 46 _inserts(0), _insert_limit( insert_limit() ),
duke@435 47 _look_probes(0), _lookup_hits(0), _lookup_misses(0),
duke@435 48 _total_insert_probes(0), _total_inserts(0),
duke@435 49 _insert_probes(0), _grows(0) {
duke@435 50 // _sentinel must be in the current node space
kvn@4115 51 _sentinel = new (Compile::current()) ProjNode(NULL, TypeFunc::Control);
duke@435 52 memset(_table,0,sizeof(Node*)*_max);
duke@435 53 }
duke@435 54
duke@435 55 //------------------------------NodeHash---------------------------------------
duke@435 56 NodeHash::NodeHash(Arena *arena, uint est_max_size) :
duke@435 57 _max( round_up(est_max_size < NODE_HASH_MINIMUM_SIZE ? NODE_HASH_MINIMUM_SIZE : est_max_size) ),
duke@435 58 _a(arena),
duke@435 59 _table( NEW_ARENA_ARRAY( _a , Node* , _max ) ),
duke@435 60 _inserts(0), _insert_limit( insert_limit() ),
duke@435 61 _look_probes(0), _lookup_hits(0), _lookup_misses(0),
duke@435 62 _delete_probes(0), _delete_hits(0), _delete_misses(0),
duke@435 63 _total_insert_probes(0), _total_inserts(0),
duke@435 64 _insert_probes(0), _grows(0) {
duke@435 65 // _sentinel must be in the current node space
kvn@4115 66 _sentinel = new (Compile::current()) ProjNode(NULL, TypeFunc::Control);
duke@435 67 memset(_table,0,sizeof(Node*)*_max);
duke@435 68 }
duke@435 69
duke@435 70 //------------------------------NodeHash---------------------------------------
duke@435 71 NodeHash::NodeHash(NodeHash *nh) {
duke@435 72 debug_only(_table = (Node**)badAddress); // interact correctly w/ operator=
duke@435 73 // just copy in all the fields
duke@435 74 *this = *nh;
duke@435 75 // nh->_sentinel must be in the current node space
duke@435 76 }
duke@435 77
roland@4409 78 void NodeHash::replace_with(NodeHash *nh) {
roland@4409 79 debug_only(_table = (Node**)badAddress); // interact correctly w/ operator=
roland@4409 80 // just copy in all the fields
roland@4409 81 *this = *nh;
roland@4409 82 // nh->_sentinel must be in the current node space
roland@4409 83 }
roland@4409 84
duke@435 85 //------------------------------hash_find--------------------------------------
duke@435 86 // Find in hash table
duke@435 87 Node *NodeHash::hash_find( const Node *n ) {
duke@435 88 // ((Node*)n)->set_hash( n->hash() );
duke@435 89 uint hash = n->hash();
duke@435 90 if (hash == Node::NO_HASH) {
duke@435 91 debug_only( _lookup_misses++ );
duke@435 92 return NULL;
duke@435 93 }
duke@435 94 uint key = hash & (_max-1);
duke@435 95 uint stride = key | 0x01;
duke@435 96 debug_only( _look_probes++ );
duke@435 97 Node *k = _table[key]; // Get hashed value
duke@435 98 if( !k ) { // ?Miss?
duke@435 99 debug_only( _lookup_misses++ );
duke@435 100 return NULL; // Miss!
duke@435 101 }
duke@435 102
duke@435 103 int op = n->Opcode();
duke@435 104 uint req = n->req();
duke@435 105 while( 1 ) { // While probing hash table
duke@435 106 if( k->req() == req && // Same count of inputs
duke@435 107 k->Opcode() == op ) { // Same Opcode
duke@435 108 for( uint i=0; i<req; i++ )
duke@435 109 if( n->in(i)!=k->in(i)) // Different inputs?
duke@435 110 goto collision; // "goto" is a speed hack...
duke@435 111 if( n->cmp(*k) ) { // Check for any special bits
duke@435 112 debug_only( _lookup_hits++ );
duke@435 113 return k; // Hit!
duke@435 114 }
duke@435 115 }
duke@435 116 collision:
duke@435 117 debug_only( _look_probes++ );
duke@435 118 key = (key + stride/*7*/) & (_max-1); // Stride through table with relative prime
duke@435 119 k = _table[key]; // Get hashed value
duke@435 120 if( !k ) { // ?Miss?
duke@435 121 debug_only( _lookup_misses++ );
duke@435 122 return NULL; // Miss!
duke@435 123 }
duke@435 124 }
duke@435 125 ShouldNotReachHere();
duke@435 126 return NULL;
duke@435 127 }
duke@435 128
duke@435 129 //------------------------------hash_find_insert-------------------------------
duke@435 130 // Find in hash table, insert if not already present
duke@435 131 // Used to preserve unique entries in hash table
duke@435 132 Node *NodeHash::hash_find_insert( Node *n ) {
duke@435 133 // n->set_hash( );
duke@435 134 uint hash = n->hash();
duke@435 135 if (hash == Node::NO_HASH) {
duke@435 136 debug_only( _lookup_misses++ );
duke@435 137 return NULL;
duke@435 138 }
duke@435 139 uint key = hash & (_max-1);
duke@435 140 uint stride = key | 0x01; // stride must be relatively prime to table siz
duke@435 141 uint first_sentinel = 0; // replace a sentinel if seen.
duke@435 142 debug_only( _look_probes++ );
duke@435 143 Node *k = _table[key]; // Get hashed value
duke@435 144 if( !k ) { // ?Miss?
duke@435 145 debug_only( _lookup_misses++ );
duke@435 146 _table[key] = n; // Insert into table!
duke@435 147 debug_only(n->enter_hash_lock()); // Lock down the node while in the table.
duke@435 148 check_grow(); // Grow table if insert hit limit
duke@435 149 return NULL; // Miss!
duke@435 150 }
duke@435 151 else if( k == _sentinel ) {
duke@435 152 first_sentinel = key; // Can insert here
duke@435 153 }
duke@435 154
duke@435 155 int op = n->Opcode();
duke@435 156 uint req = n->req();
duke@435 157 while( 1 ) { // While probing hash table
duke@435 158 if( k->req() == req && // Same count of inputs
duke@435 159 k->Opcode() == op ) { // Same Opcode
duke@435 160 for( uint i=0; i<req; i++ )
duke@435 161 if( n->in(i)!=k->in(i)) // Different inputs?
duke@435 162 goto collision; // "goto" is a speed hack...
duke@435 163 if( n->cmp(*k) ) { // Check for any special bits
duke@435 164 debug_only( _lookup_hits++ );
duke@435 165 return k; // Hit!
duke@435 166 }
duke@435 167 }
duke@435 168 collision:
duke@435 169 debug_only( _look_probes++ );
duke@435 170 key = (key + stride) & (_max-1); // Stride through table w/ relative prime
duke@435 171 k = _table[key]; // Get hashed value
duke@435 172 if( !k ) { // ?Miss?
duke@435 173 debug_only( _lookup_misses++ );
duke@435 174 key = (first_sentinel == 0) ? key : first_sentinel; // ?saw sentinel?
duke@435 175 _table[key] = n; // Insert into table!
duke@435 176 debug_only(n->enter_hash_lock()); // Lock down the node while in the table.
duke@435 177 check_grow(); // Grow table if insert hit limit
duke@435 178 return NULL; // Miss!
duke@435 179 }
duke@435 180 else if( first_sentinel == 0 && k == _sentinel ) {
duke@435 181 first_sentinel = key; // Can insert here
duke@435 182 }
duke@435 183
duke@435 184 }
duke@435 185 ShouldNotReachHere();
duke@435 186 return NULL;
duke@435 187 }
duke@435 188
duke@435 189 //------------------------------hash_insert------------------------------------
duke@435 190 // Insert into hash table
duke@435 191 void NodeHash::hash_insert( Node *n ) {
duke@435 192 // // "conflict" comments -- print nodes that conflict
duke@435 193 // bool conflict = false;
duke@435 194 // n->set_hash();
duke@435 195 uint hash = n->hash();
duke@435 196 if (hash == Node::NO_HASH) {
duke@435 197 return;
duke@435 198 }
duke@435 199 check_grow();
duke@435 200 uint key = hash & (_max-1);
duke@435 201 uint stride = key | 0x01;
duke@435 202
duke@435 203 while( 1 ) { // While probing hash table
duke@435 204 debug_only( _insert_probes++ );
duke@435 205 Node *k = _table[key]; // Get hashed value
duke@435 206 if( !k || (k == _sentinel) ) break; // Found a slot
duke@435 207 assert( k != n, "already inserted" );
duke@435 208 // if( PrintCompilation && PrintOptoStatistics && Verbose ) { tty->print(" conflict: "); k->dump(); conflict = true; }
duke@435 209 key = (key + stride) & (_max-1); // Stride through table w/ relative prime
duke@435 210 }
duke@435 211 _table[key] = n; // Insert into table!
duke@435 212 debug_only(n->enter_hash_lock()); // Lock down the node while in the table.
duke@435 213 // if( conflict ) { n->dump(); }
duke@435 214 }
duke@435 215
duke@435 216 //------------------------------hash_delete------------------------------------
twisti@1040 217 // Replace in hash table with sentinel
duke@435 218 bool NodeHash::hash_delete( const Node *n ) {
duke@435 219 Node *k;
duke@435 220 uint hash = n->hash();
duke@435 221 if (hash == Node::NO_HASH) {
duke@435 222 debug_only( _delete_misses++ );
duke@435 223 return false;
duke@435 224 }
duke@435 225 uint key = hash & (_max-1);
duke@435 226 uint stride = key | 0x01;
duke@435 227 debug_only( uint counter = 0; );
twisti@1040 228 for( ; /* (k != NULL) && (k != _sentinel) */; ) {
duke@435 229 debug_only( counter++ );
duke@435 230 debug_only( _delete_probes++ );
duke@435 231 k = _table[key]; // Get hashed value
duke@435 232 if( !k ) { // Miss?
duke@435 233 debug_only( _delete_misses++ );
duke@435 234 #ifdef ASSERT
duke@435 235 if( VerifyOpto ) {
duke@435 236 for( uint i=0; i < _max; i++ )
duke@435 237 assert( _table[i] != n, "changed edges with rehashing" );
duke@435 238 }
duke@435 239 #endif
duke@435 240 return false; // Miss! Not in chain
duke@435 241 }
duke@435 242 else if( n == k ) {
duke@435 243 debug_only( _delete_hits++ );
duke@435 244 _table[key] = _sentinel; // Hit! Label as deleted entry
duke@435 245 debug_only(((Node*)n)->exit_hash_lock()); // Unlock the node upon removal from table.
duke@435 246 return true;
duke@435 247 }
duke@435 248 else {
duke@435 249 // collision: move through table with prime offset
duke@435 250 key = (key + stride/*7*/) & (_max-1);
duke@435 251 assert( counter <= _insert_limit, "Cycle in hash-table");
duke@435 252 }
duke@435 253 }
duke@435 254 ShouldNotReachHere();
duke@435 255 return false;
duke@435 256 }
duke@435 257
duke@435 258 //------------------------------round_up---------------------------------------
duke@435 259 // Round up to nearest power of 2
duke@435 260 uint NodeHash::round_up( uint x ) {
duke@435 261 x += (x>>2); // Add 25% slop
duke@435 262 if( x <16 ) return 16; // Small stuff
duke@435 263 uint i=16;
duke@435 264 while( i < x ) i <<= 1; // Double to fit
duke@435 265 return i; // Return hash table size
duke@435 266 }
duke@435 267
duke@435 268 //------------------------------grow-------------------------------------------
duke@435 269 // Grow _table to next power of 2 and insert old entries
duke@435 270 void NodeHash::grow() {
duke@435 271 // Record old state
duke@435 272 uint old_max = _max;
duke@435 273 Node **old_table = _table;
duke@435 274 // Construct new table with twice the space
duke@435 275 _grows++;
duke@435 276 _total_inserts += _inserts;
duke@435 277 _total_insert_probes += _insert_probes;
duke@435 278 _inserts = 0;
duke@435 279 _insert_probes = 0;
duke@435 280 _max = _max << 1;
duke@435 281 _table = NEW_ARENA_ARRAY( _a , Node* , _max ); // (Node**)_a->Amalloc( _max * sizeof(Node*) );
duke@435 282 memset(_table,0,sizeof(Node*)*_max);
duke@435 283 _insert_limit = insert_limit();
duke@435 284 // Insert old entries into the new table
duke@435 285 for( uint i = 0; i < old_max; i++ ) {
duke@435 286 Node *m = *old_table++;
duke@435 287 if( !m || m == _sentinel ) continue;
duke@435 288 debug_only(m->exit_hash_lock()); // Unlock the node upon removal from old table.
duke@435 289 hash_insert(m);
duke@435 290 }
duke@435 291 }
duke@435 292
duke@435 293 //------------------------------clear------------------------------------------
duke@435 294 // Clear all entries in _table to NULL but keep storage
duke@435 295 void NodeHash::clear() {
duke@435 296 #ifdef ASSERT
duke@435 297 // Unlock all nodes upon removal from table.
duke@435 298 for (uint i = 0; i < _max; i++) {
duke@435 299 Node* n = _table[i];
duke@435 300 if (!n || n == _sentinel) continue;
duke@435 301 n->exit_hash_lock();
duke@435 302 }
duke@435 303 #endif
duke@435 304
duke@435 305 memset( _table, 0, _max * sizeof(Node*) );
duke@435 306 }
duke@435 307
duke@435 308 //-----------------------remove_useless_nodes----------------------------------
duke@435 309 // Remove useless nodes from value table,
duke@435 310 // implementation does not depend on hash function
duke@435 311 void NodeHash::remove_useless_nodes(VectorSet &useful) {
duke@435 312
duke@435 313 // Dead nodes in the hash table inherited from GVN should not replace
duke@435 314 // existing nodes, remove dead nodes.
duke@435 315 uint max = size();
duke@435 316 Node *sentinel_node = sentinel();
duke@435 317 for( uint i = 0; i < max; ++i ) {
duke@435 318 Node *n = at(i);
duke@435 319 if(n != NULL && n != sentinel_node && !useful.test(n->_idx)) {
duke@435 320 debug_only(n->exit_hash_lock()); // Unlock the node when removed
duke@435 321 _table[i] = sentinel_node; // Replace with placeholder
duke@435 322 }
duke@435 323 }
duke@435 324 }
duke@435 325
roland@6313 326
roland@6313 327 void NodeHash::check_no_speculative_types() {
roland@6313 328 #ifdef ASSERT
roland@6313 329 uint max = size();
roland@6313 330 Node *sentinel_node = sentinel();
roland@6313 331 for (uint i = 0; i < max; ++i) {
roland@6313 332 Node *n = at(i);
roland@6313 333 if(n != NULL && n != sentinel_node && n->is_Type()) {
roland@6313 334 TypeNode* tn = n->as_Type();
roland@6313 335 const Type* t = tn->type();
roland@6313 336 const Type* t_no_spec = t->remove_speculative();
roland@6313 337 assert(t == t_no_spec, "dead node in hash table or missed node during speculative cleanup");
roland@6313 338 }
roland@6313 339 }
roland@6313 340 #endif
roland@6313 341 }
roland@6313 342
duke@435 343 #ifndef PRODUCT
duke@435 344 //------------------------------dump-------------------------------------------
duke@435 345 // Dump statistics for the hash table
duke@435 346 void NodeHash::dump() {
duke@435 347 _total_inserts += _inserts;
duke@435 348 _total_insert_probes += _insert_probes;
kvn@3260 349 if (PrintCompilation && PrintOptoStatistics && Verbose && (_inserts > 0)) {
kvn@3260 350 if (WizardMode) {
kvn@3260 351 for (uint i=0; i<_max; i++) {
kvn@3260 352 if (_table[i])
kvn@3260 353 tty->print("%d/%d/%d ",i,_table[i]->hash()&(_max-1),_table[i]->_idx);
kvn@3260 354 }
duke@435 355 }
duke@435 356 tty->print("\nGVN Hash stats: %d grows to %d max_size\n", _grows, _max);
duke@435 357 tty->print(" %d/%d (%8.1f%% full)\n", _inserts, _max, (double)_inserts/_max*100.0);
duke@435 358 tty->print(" %dp/(%dh+%dm) (%8.2f probes/lookup)\n", _look_probes, _lookup_hits, _lookup_misses, (double)_look_probes/(_lookup_hits+_lookup_misses));
duke@435 359 tty->print(" %dp/%di (%8.2f probes/insert)\n", _total_insert_probes, _total_inserts, (double)_total_insert_probes/_total_inserts);
duke@435 360 // sentinels increase lookup cost, but not insert cost
duke@435 361 assert((_lookup_misses+_lookup_hits)*4+100 >= _look_probes, "bad hash function");
duke@435 362 assert( _inserts+(_inserts>>3) < _max, "table too full" );
duke@435 363 assert( _inserts*3+100 >= _insert_probes, "bad hash function" );
duke@435 364 }
duke@435 365 }
duke@435 366
duke@435 367 Node *NodeHash::find_index(uint idx) { // For debugging
duke@435 368 // Find an entry by its index value
duke@435 369 for( uint i = 0; i < _max; i++ ) {
duke@435 370 Node *m = _table[i];
duke@435 371 if( !m || m == _sentinel ) continue;
duke@435 372 if( m->_idx == (uint)idx ) return m;
duke@435 373 }
duke@435 374 return NULL;
duke@435 375 }
duke@435 376 #endif
duke@435 377
duke@435 378 #ifdef ASSERT
duke@435 379 NodeHash::~NodeHash() {
duke@435 380 // Unlock all nodes upon destruction of table.
duke@435 381 if (_table != (Node**)badAddress) clear();
duke@435 382 }
duke@435 383
duke@435 384 void NodeHash::operator=(const NodeHash& nh) {
duke@435 385 // Unlock all nodes upon replacement of table.
duke@435 386 if (&nh == this) return;
duke@435 387 if (_table != (Node**)badAddress) clear();
duke@435 388 memcpy(this, &nh, sizeof(*this));
duke@435 389 // Do not increment hash_lock counts again.
duke@435 390 // Instead, be sure we never again use the source table.
duke@435 391 ((NodeHash*)&nh)->_table = (Node**)badAddress;
duke@435 392 }
duke@435 393
duke@435 394
duke@435 395 #endif
duke@435 396
duke@435 397
duke@435 398 //=============================================================================
duke@435 399 //------------------------------PhaseRemoveUseless-----------------------------
duke@435 400 // 1) Use a breadthfirst walk to collect useful nodes reachable from root.
zmajo@8193 401 PhaseRemoveUseless::PhaseRemoveUseless(PhaseGVN *gvn, Unique_Node_List *worklist, PhaseNumber phase_num) : Phase(phase_num),
duke@435 402 _useful(Thread::current()->resource_area()) {
duke@435 403
duke@435 404 // Implementation requires 'UseLoopSafepoints == true' and an edge from root
duke@435 405 // to each SafePointNode at a backward branch. Inserted in add_safepoint().
duke@435 406 if( !UseLoopSafepoints || !OptoRemoveUseless ) return;
duke@435 407
duke@435 408 // Identify nodes that are reachable from below, useful.
duke@435 409 C->identify_useful_nodes(_useful);
bharadwaj@4315 410 // Update dead node list
bharadwaj@4315 411 C->update_dead_node_list(_useful);
duke@435 412
duke@435 413 // Remove all useless nodes from PhaseValues' recorded types
duke@435 414 // Must be done before disconnecting nodes to preserve hash-table-invariant
duke@435 415 gvn->remove_useless_nodes(_useful.member_set());
duke@435 416
duke@435 417 // Remove all useless nodes from future worklist
duke@435 418 worklist->remove_useless_nodes(_useful.member_set());
duke@435 419
duke@435 420 // Disconnect 'useless' nodes that are adjacent to useful nodes
duke@435 421 C->remove_useless_nodes(_useful);
duke@435 422
duke@435 423 // Remove edges from "root" to each SafePoint at a backward branch.
duke@435 424 // They were inserted during parsing (see add_safepoint()) to make infinite
duke@435 425 // loops without calls or exceptions visible to root, i.e., useful.
duke@435 426 Node *root = C->root();
duke@435 427 if( root != NULL ) {
duke@435 428 for( uint i = root->req(); i < root->len(); ++i ) {
duke@435 429 Node *n = root->in(i);
duke@435 430 if( n != NULL && n->is_SafePoint() ) {
duke@435 431 root->rm_prec(i);
duke@435 432 --i;
duke@435 433 }
duke@435 434 }
duke@435 435 }
duke@435 436 }
duke@435 437
zmajo@8193 438 //=============================================================================
zmajo@8193 439 //------------------------------PhaseRenumberLive------------------------------
zmajo@8193 440 // First, remove useless nodes (equivalent to identifying live nodes).
zmajo@8193 441 // Then, renumber live nodes.
zmajo@8193 442 //
zmajo@8193 443 // The set of live nodes is returned by PhaseRemoveUseless in the _useful structure.
zmajo@8193 444 // If the number of live nodes is 'x' (where 'x' == _useful.size()), then the
zmajo@8193 445 // PhaseRenumberLive updates the node ID of each node (the _idx field) with a unique
zmajo@8193 446 // value in the range [0, x).
zmajo@8193 447 //
zmajo@8193 448 // At the end of the PhaseRenumberLive phase, the compiler's count of unique nodes is
zmajo@8193 449 // updated to 'x' and the list of dead nodes is reset (as there are no dead nodes).
zmajo@8193 450 //
zmajo@8193 451 // The PhaseRenumberLive phase updates two data structures with the new node IDs.
zmajo@8193 452 // (1) The worklist is used by the PhaseIterGVN phase to identify nodes that must be
zmajo@8193 453 // processed. A new worklist (with the updated node IDs) is returned in 'new_worklist'.
zmajo@8193 454 // (2) Type information (the field PhaseGVN::_types) maps type information to each
zmajo@8193 455 // node ID. The mapping is updated to use the new node IDs as well. Updated type
zmajo@8193 456 // information is returned in PhaseGVN::_types.
zmajo@8193 457 //
zmajo@8193 458 // The PhaseRenumberLive phase does not preserve the order of elements in the worklist.
zmajo@8193 459 //
zmajo@8193 460 // Other data structures used by the compiler are not updated. The hash table for value
zmajo@8193 461 // numbering (the field PhaseGVN::_table) is not updated because computing the hash
zmajo@8193 462 // values is not based on node IDs. The field PhaseGVN::_nodes is not updated either
zmajo@8193 463 // because it is empty wherever PhaseRenumberLive is used.
zmajo@8193 464 PhaseRenumberLive::PhaseRenumberLive(PhaseGVN* gvn,
zmajo@8193 465 Unique_Node_List* worklist, Unique_Node_List* new_worklist,
zmajo@8193 466 PhaseNumber phase_num) :
zmajo@8193 467 PhaseRemoveUseless(gvn, worklist, Remove_Useless_And_Renumber_Live) {
zmajo@8193 468
zmajo@8193 469 assert(RenumberLiveNodes, "RenumberLiveNodes must be set to true for node renumbering to take place");
zmajo@8193 470 assert(C->live_nodes() == _useful.size(), "the number of live nodes must match the number of useful nodes");
zmajo@8193 471 assert(gvn->nodes_size() == 0, "GVN must not contain any nodes at this point");
zmajo@8193 472
zmajo@8193 473 uint old_unique_count = C->unique();
zmajo@8193 474 uint live_node_count = C->live_nodes();
zmajo@8193 475 uint worklist_size = worklist->size();
zmajo@8193 476
zmajo@8193 477 // Storage for the updated type information.
zmajo@8193 478 Type_Array new_type_array(C->comp_arena());
zmajo@8193 479
zmajo@8193 480 // Iterate over the set of live nodes.
zmajo@8193 481 uint current_idx = 0; // The current new node ID. Incremented after every assignment.
zmajo@8193 482 for (uint i = 0; i < _useful.size(); i++) {
zmajo@8193 483 Node* n = _useful.at(i);
poonam@8945 484 // Sanity check that fails if we ever decide to execute this phase after EA
poonam@8945 485 assert(!n->is_Phi() || n->as_Phi()->inst_mem_id() == -1, "should not be linked to data Phi");
zmajo@8193 486 const Type* type = gvn->type_or_null(n);
zmajo@8193 487 new_type_array.map(current_idx, type);
zmajo@8193 488
zmajo@8193 489 bool in_worklist = false;
zmajo@8193 490 if (worklist->member(n)) {
zmajo@8193 491 in_worklist = true;
zmajo@8193 492 }
zmajo@8193 493
zmajo@8193 494 n->set_idx(current_idx); // Update node ID.
zmajo@8193 495
zmajo@8193 496 if (in_worklist) {
zmajo@8193 497 new_worklist->push(n);
zmajo@8193 498 }
zmajo@8193 499
zmajo@8193 500 current_idx++;
zmajo@8193 501 }
zmajo@8193 502
zmajo@8193 503 assert(worklist_size == new_worklist->size(), "the new worklist must have the same size as the original worklist");
zmajo@8193 504 assert(live_node_count == current_idx, "all live nodes must be processed");
zmajo@8193 505
zmajo@8193 506 // Replace the compiler's type information with the updated type information.
zmajo@8193 507 gvn->replace_types(new_type_array);
zmajo@8193 508
zmajo@8193 509 // Update the unique node count of the compilation to the number of currently live nodes.
zmajo@8193 510 C->set_unique(live_node_count);
zmajo@8193 511
zmajo@8193 512 // Set the dead node count to 0 and reset dead node list.
zmajo@8193 513 C->reset_dead_node_list();
zmajo@8193 514 }
zmajo@8193 515
duke@435 516
duke@435 517 //=============================================================================
duke@435 518 //------------------------------PhaseTransform---------------------------------
duke@435 519 PhaseTransform::PhaseTransform( PhaseNumber pnum ) : Phase(pnum),
duke@435 520 _arena(Thread::current()->resource_area()),
duke@435 521 _nodes(_arena),
duke@435 522 _types(_arena)
duke@435 523 {
duke@435 524 init_con_caches();
duke@435 525 #ifndef PRODUCT
duke@435 526 clear_progress();
duke@435 527 clear_transforms();
duke@435 528 set_allow_progress(true);
duke@435 529 #endif
duke@435 530 // Force allocation for currently existing nodes
duke@435 531 _types.map(C->unique(), NULL);
duke@435 532 }
duke@435 533
duke@435 534 //------------------------------PhaseTransform---------------------------------
duke@435 535 PhaseTransform::PhaseTransform( Arena *arena, PhaseNumber pnum ) : Phase(pnum),
duke@435 536 _arena(arena),
duke@435 537 _nodes(arena),
duke@435 538 _types(arena)
duke@435 539 {
duke@435 540 init_con_caches();
duke@435 541 #ifndef PRODUCT
duke@435 542 clear_progress();
duke@435 543 clear_transforms();
duke@435 544 set_allow_progress(true);
duke@435 545 #endif
duke@435 546 // Force allocation for currently existing nodes
duke@435 547 _types.map(C->unique(), NULL);
duke@435 548 }
duke@435 549
duke@435 550 //------------------------------PhaseTransform---------------------------------
duke@435 551 // Initialize with previously generated type information
duke@435 552 PhaseTransform::PhaseTransform( PhaseTransform *pt, PhaseNumber pnum ) : Phase(pnum),
duke@435 553 _arena(pt->_arena),
duke@435 554 _nodes(pt->_nodes),
duke@435 555 _types(pt->_types)
duke@435 556 {
duke@435 557 init_con_caches();
duke@435 558 #ifndef PRODUCT
duke@435 559 clear_progress();
duke@435 560 clear_transforms();
duke@435 561 set_allow_progress(true);
duke@435 562 #endif
duke@435 563 }
duke@435 564
duke@435 565 void PhaseTransform::init_con_caches() {
duke@435 566 memset(_icons,0,sizeof(_icons));
duke@435 567 memset(_lcons,0,sizeof(_lcons));
duke@435 568 memset(_zcons,0,sizeof(_zcons));
duke@435 569 }
duke@435 570
duke@435 571
duke@435 572 //--------------------------------find_int_type--------------------------------
duke@435 573 const TypeInt* PhaseTransform::find_int_type(Node* n) {
duke@435 574 if (n == NULL) return NULL;
duke@435 575 // Call type_or_null(n) to determine node's type since we might be in
duke@435 576 // parse phase and call n->Value() may return wrong type.
duke@435 577 // (For example, a phi node at the beginning of loop parsing is not ready.)
duke@435 578 const Type* t = type_or_null(n);
duke@435 579 if (t == NULL) return NULL;
duke@435 580 return t->isa_int();
duke@435 581 }
duke@435 582
duke@435 583
duke@435 584 //-------------------------------find_long_type--------------------------------
duke@435 585 const TypeLong* PhaseTransform::find_long_type(Node* n) {
duke@435 586 if (n == NULL) return NULL;
duke@435 587 // (See comment above on type_or_null.)
duke@435 588 const Type* t = type_or_null(n);
duke@435 589 if (t == NULL) return NULL;
duke@435 590 return t->isa_long();
duke@435 591 }
duke@435 592
duke@435 593
duke@435 594 #ifndef PRODUCT
duke@435 595 void PhaseTransform::dump_old2new_map() const {
duke@435 596 _nodes.dump();
duke@435 597 }
duke@435 598
duke@435 599 void PhaseTransform::dump_new( uint nidx ) const {
duke@435 600 for( uint i=0; i<_nodes.Size(); i++ )
duke@435 601 if( _nodes[i] && _nodes[i]->_idx == nidx ) {
duke@435 602 _nodes[i]->dump();
duke@435 603 tty->cr();
duke@435 604 tty->print_cr("Old index= %d",i);
duke@435 605 return;
duke@435 606 }
duke@435 607 tty->print_cr("Node %d not found in the new indices", nidx);
duke@435 608 }
duke@435 609
duke@435 610 //------------------------------dump_types-------------------------------------
duke@435 611 void PhaseTransform::dump_types( ) const {
duke@435 612 _types.dump();
duke@435 613 }
duke@435 614
duke@435 615 //------------------------------dump_nodes_and_types---------------------------
duke@435 616 void PhaseTransform::dump_nodes_and_types(const Node *root, uint depth, bool only_ctrl) {
duke@435 617 VectorSet visited(Thread::current()->resource_area());
duke@435 618 dump_nodes_and_types_recur( root, depth, only_ctrl, visited );
duke@435 619 }
duke@435 620
duke@435 621 //------------------------------dump_nodes_and_types_recur---------------------
duke@435 622 void PhaseTransform::dump_nodes_and_types_recur( const Node *n, uint depth, bool only_ctrl, VectorSet &visited) {
duke@435 623 if( !n ) return;
duke@435 624 if( depth == 0 ) return;
duke@435 625 if( visited.test_set(n->_idx) ) return;
duke@435 626 for( uint i=0; i<n->len(); i++ ) {
duke@435 627 if( only_ctrl && !(n->is_Region()) && i != TypeFunc::Control ) continue;
duke@435 628 dump_nodes_and_types_recur( n->in(i), depth-1, only_ctrl, visited );
duke@435 629 }
duke@435 630 n->dump();
duke@435 631 if (type_or_null(n) != NULL) {
duke@435 632 tty->print(" "); type(n)->dump(); tty->cr();
duke@435 633 }
duke@435 634 }
duke@435 635
duke@435 636 #endif
duke@435 637
duke@435 638
duke@435 639 //=============================================================================
duke@435 640 //------------------------------PhaseValues------------------------------------
duke@435 641 // Set minimum table size to "255"
duke@435 642 PhaseValues::PhaseValues( Arena *arena, uint est_max_size ) : PhaseTransform(arena, GVN), _table(arena, est_max_size) {
duke@435 643 NOT_PRODUCT( clear_new_values(); )
duke@435 644 }
duke@435 645
duke@435 646 //------------------------------PhaseValues------------------------------------
duke@435 647 // Set minimum table size to "255"
duke@435 648 PhaseValues::PhaseValues( PhaseValues *ptv ) : PhaseTransform( ptv, GVN ),
duke@435 649 _table(&ptv->_table) {
duke@435 650 NOT_PRODUCT( clear_new_values(); )
duke@435 651 }
duke@435 652
duke@435 653 //------------------------------PhaseValues------------------------------------
duke@435 654 // Used by +VerifyOpto. Clear out hash table but copy _types array.
duke@435 655 PhaseValues::PhaseValues( PhaseValues *ptv, const char *dummy ) : PhaseTransform( ptv, GVN ),
duke@435 656 _table(ptv->arena(),ptv->_table.size()) {
duke@435 657 NOT_PRODUCT( clear_new_values(); )
duke@435 658 }
duke@435 659
duke@435 660 //------------------------------~PhaseValues-----------------------------------
duke@435 661 #ifndef PRODUCT
duke@435 662 PhaseValues::~PhaseValues() {
duke@435 663 _table.dump();
duke@435 664
duke@435 665 // Statistics for value progress and efficiency
duke@435 666 if( PrintCompilation && Verbose && WizardMode ) {
duke@435 667 tty->print("\n%sValues: %d nodes ---> %d/%d (%d)",
duke@435 668 is_IterGVN() ? "Iter" : " ", C->unique(), made_progress(), made_transforms(), made_new_values());
duke@435 669 if( made_transforms() != 0 ) {
duke@435 670 tty->print_cr(" ratio %f", made_progress()/(float)made_transforms() );
duke@435 671 } else {
duke@435 672 tty->cr();
duke@435 673 }
duke@435 674 }
duke@435 675 }
duke@435 676 #endif
duke@435 677
duke@435 678 //------------------------------makecon----------------------------------------
duke@435 679 ConNode* PhaseTransform::makecon(const Type *t) {
duke@435 680 assert(t->singleton(), "must be a constant");
duke@435 681 assert(!t->empty() || t == Type::TOP, "must not be vacuous range");
duke@435 682 switch (t->base()) { // fast paths
duke@435 683 case Type::Half:
duke@435 684 case Type::Top: return (ConNode*) C->top();
duke@435 685 case Type::Int: return intcon( t->is_int()->get_con() );
duke@435 686 case Type::Long: return longcon( t->is_long()->get_con() );
duke@435 687 }
duke@435 688 if (t->is_zero_type())
duke@435 689 return zerocon(t->basic_type());
duke@435 690 return uncached_makecon(t);
duke@435 691 }
duke@435 692
duke@435 693 //--------------------------uncached_makecon-----------------------------------
duke@435 694 // Make an idealized constant - one of ConINode, ConPNode, etc.
duke@435 695 ConNode* PhaseValues::uncached_makecon(const Type *t) {
duke@435 696 assert(t->singleton(), "must be a constant");
duke@435 697 ConNode* x = ConNode::make(C, t);
duke@435 698 ConNode* k = (ConNode*)hash_find_insert(x); // Value numbering
duke@435 699 if (k == NULL) {
duke@435 700 set_type(x, t); // Missed, provide type mapping
duke@435 701 GrowableArray<Node_Notes*>* nna = C->node_note_array();
duke@435 702 if (nna != NULL) {
duke@435 703 Node_Notes* loc = C->locate_node_notes(nna, x->_idx, true);
duke@435 704 loc->clear(); // do not put debug info on constants
duke@435 705 }
duke@435 706 } else {
duke@435 707 x->destruct(); // Hit, destroy duplicate constant
duke@435 708 x = k; // use existing constant
duke@435 709 }
duke@435 710 return x;
duke@435 711 }
duke@435 712
duke@435 713 //------------------------------intcon-----------------------------------------
duke@435 714 // Fast integer constant. Same as "transform(new ConINode(TypeInt::make(i)))"
duke@435 715 ConINode* PhaseTransform::intcon(int i) {
duke@435 716 // Small integer? Check cache! Check that cached node is not dead
duke@435 717 if (i >= _icon_min && i <= _icon_max) {
duke@435 718 ConINode* icon = _icons[i-_icon_min];
duke@435 719 if (icon != NULL && icon->in(TypeFunc::Control) != NULL)
duke@435 720 return icon;
duke@435 721 }
duke@435 722 ConINode* icon = (ConINode*) uncached_makecon(TypeInt::make(i));
duke@435 723 assert(icon->is_Con(), "");
duke@435 724 if (i >= _icon_min && i <= _icon_max)
duke@435 725 _icons[i-_icon_min] = icon; // Cache small integers
duke@435 726 return icon;
duke@435 727 }
duke@435 728
duke@435 729 //------------------------------longcon----------------------------------------
duke@435 730 // Fast long constant.
duke@435 731 ConLNode* PhaseTransform::longcon(jlong l) {
duke@435 732 // Small integer? Check cache! Check that cached node is not dead
duke@435 733 if (l >= _lcon_min && l <= _lcon_max) {
duke@435 734 ConLNode* lcon = _lcons[l-_lcon_min];
duke@435 735 if (lcon != NULL && lcon->in(TypeFunc::Control) != NULL)
duke@435 736 return lcon;
duke@435 737 }
duke@435 738 ConLNode* lcon = (ConLNode*) uncached_makecon(TypeLong::make(l));
duke@435 739 assert(lcon->is_Con(), "");
duke@435 740 if (l >= _lcon_min && l <= _lcon_max)
duke@435 741 _lcons[l-_lcon_min] = lcon; // Cache small integers
duke@435 742 return lcon;
duke@435 743 }
duke@435 744
duke@435 745 //------------------------------zerocon-----------------------------------------
duke@435 746 // Fast zero or null constant. Same as "transform(ConNode::make(Type::get_zero_type(bt)))"
duke@435 747 ConNode* PhaseTransform::zerocon(BasicType bt) {
duke@435 748 assert((uint)bt <= _zcon_max, "domain check");
duke@435 749 ConNode* zcon = _zcons[bt];
duke@435 750 if (zcon != NULL && zcon->in(TypeFunc::Control) != NULL)
duke@435 751 return zcon;
duke@435 752 zcon = (ConNode*) uncached_makecon(Type::get_zero_type(bt));
duke@435 753 _zcons[bt] = zcon;
duke@435 754 return zcon;
duke@435 755 }
duke@435 756
duke@435 757
duke@435 758
duke@435 759 //=============================================================================
duke@435 760 //------------------------------transform--------------------------------------
duke@435 761 // Return a node which computes the same function as this node, but in a
kvn@476 762 // faster or cheaper fashion.
duke@435 763 Node *PhaseGVN::transform( Node *n ) {
kvn@476 764 return transform_no_reclaim(n);
duke@435 765 }
duke@435 766
duke@435 767 //------------------------------transform--------------------------------------
duke@435 768 // Return a node which computes the same function as this node, but
duke@435 769 // in a faster or cheaper fashion.
duke@435 770 Node *PhaseGVN::transform_no_reclaim( Node *n ) {
duke@435 771 NOT_PRODUCT( set_transforms(); )
duke@435 772
duke@435 773 // Apply the Ideal call in a loop until it no longer applies
duke@435 774 Node *k = n;
duke@435 775 NOT_PRODUCT( uint loop_count = 0; )
duke@435 776 while( 1 ) {
duke@435 777 Node *i = k->Ideal(this, /*can_reshape=*/false);
duke@435 778 if( !i ) break;
duke@435 779 assert( i->_idx >= k->_idx, "Idealize should return new nodes, use Identity to return old nodes" );
duke@435 780 k = i;
duke@435 781 assert(loop_count++ < K, "infinite loop in PhaseGVN::transform");
duke@435 782 }
duke@435 783 NOT_PRODUCT( if( loop_count != 0 ) { set_progress(); } )
duke@435 784
duke@435 785
duke@435 786 // If brand new node, make space in type array.
duke@435 787 ensure_type_or_null(k);
duke@435 788
duke@435 789 // Since I just called 'Value' to compute the set of run-time values
duke@435 790 // for this Node, and 'Value' is non-local (and therefore expensive) I'll
duke@435 791 // cache Value. Later requests for the local phase->type of this Node can
duke@435 792 // use the cached Value instead of suffering with 'bottom_type'.
duke@435 793 const Type *t = k->Value(this); // Get runtime Value set
duke@435 794 assert(t != NULL, "value sanity");
duke@435 795 if (type_or_null(k) != t) {
duke@435 796 #ifndef PRODUCT
duke@435 797 // Do not count initial visit to node as a transformation
duke@435 798 if (type_or_null(k) == NULL) {
duke@435 799 inc_new_values();
duke@435 800 set_progress();
duke@435 801 }
duke@435 802 #endif
duke@435 803 set_type(k, t);
duke@435 804 // If k is a TypeNode, capture any more-precise type permanently into Node
duke@435 805 k->raise_bottom_type(t);
duke@435 806 }
duke@435 807
duke@435 808 if( t->singleton() && !k->is_Con() ) {
duke@435 809 NOT_PRODUCT( set_progress(); )
duke@435 810 return makecon(t); // Turn into a constant
duke@435 811 }
duke@435 812
duke@435 813 // Now check for Identities
duke@435 814 Node *i = k->Identity(this); // Look for a nearby replacement
duke@435 815 if( i != k ) { // Found? Return replacement!
duke@435 816 NOT_PRODUCT( set_progress(); )
duke@435 817 return i;
duke@435 818 }
duke@435 819
duke@435 820 // Global Value Numbering
duke@435 821 i = hash_find_insert(k); // Insert if new
duke@435 822 if( i && (i != k) ) {
duke@435 823 // Return the pre-existing node
duke@435 824 NOT_PRODUCT( set_progress(); )
duke@435 825 return i;
duke@435 826 }
duke@435 827
duke@435 828 // Return Idealized original
duke@435 829 return k;
duke@435 830 }
duke@435 831
duke@435 832 #ifdef ASSERT
duke@435 833 //------------------------------dead_loop_check--------------------------------
twisti@1040 834 // Check for a simple dead loop when a data node references itself directly
duke@435 835 // or through an other data node excluding cons and phis.
duke@435 836 void PhaseGVN::dead_loop_check( Node *n ) {
duke@435 837 // Phi may reference itself in a loop
duke@435 838 if (n != NULL && !n->is_dead_loop_safe() && !n->is_CFG()) {
duke@435 839 // Do 2 levels check and only data inputs.
duke@435 840 bool no_dead_loop = true;
duke@435 841 uint cnt = n->req();
duke@435 842 for (uint i = 1; i < cnt && no_dead_loop; i++) {
duke@435 843 Node *in = n->in(i);
duke@435 844 if (in == n) {
duke@435 845 no_dead_loop = false;
duke@435 846 } else if (in != NULL && !in->is_dead_loop_safe()) {
duke@435 847 uint icnt = in->req();
duke@435 848 for (uint j = 1; j < icnt && no_dead_loop; j++) {
duke@435 849 if (in->in(j) == n || in->in(j) == in)
duke@435 850 no_dead_loop = false;
duke@435 851 }
duke@435 852 }
duke@435 853 }
duke@435 854 if (!no_dead_loop) n->dump(3);
duke@435 855 assert(no_dead_loop, "dead loop detected");
duke@435 856 }
duke@435 857 }
duke@435 858 #endif
duke@435 859
duke@435 860 //=============================================================================
duke@435 861 //------------------------------PhaseIterGVN-----------------------------------
duke@435 862 // Initialize hash table to fresh and clean for +VerifyOpto
coleenp@548 863 PhaseIterGVN::PhaseIterGVN( PhaseIterGVN *igvn, const char *dummy ) : PhaseGVN(igvn,dummy), _worklist( ),
zmajo@8068 864 _stack(C->live_nodes() >> 1),
coleenp@548 865 _delay_transform(false) {
duke@435 866 }
duke@435 867
duke@435 868 //------------------------------PhaseIterGVN-----------------------------------
duke@435 869 // Initialize with previous PhaseIterGVN info; used by PhaseCCP
duke@435 870 PhaseIterGVN::PhaseIterGVN( PhaseIterGVN *igvn ) : PhaseGVN(igvn),
coleenp@548 871 _worklist( igvn->_worklist ),
dlong@3947 872 _stack( igvn->_stack ),
coleenp@548 873 _delay_transform(igvn->_delay_transform)
duke@435 874 {
duke@435 875 }
duke@435 876
duke@435 877 //------------------------------PhaseIterGVN-----------------------------------
duke@435 878 // Initialize with previous PhaseGVN info from Parser
duke@435 879 PhaseIterGVN::PhaseIterGVN( PhaseGVN *gvn ) : PhaseGVN(gvn),
coleenp@548 880 _worklist(*C->for_igvn()),
zmajo@8068 881 // TODO: Before incremental inlining it was allocated only once and it was fine. Now that
zmajo@8068 882 // the constructor is used in incremental inlining, this consumes too much memory:
zmajo@8068 883 // _stack(C->live_nodes() >> 1),
zmajo@8068 884 // So, as a band-aid, we replace this by:
zmajo@8068 885 _stack(C->comp_arena(), 32),
coleenp@548 886 _delay_transform(false)
duke@435 887 {
duke@435 888 uint max;
duke@435 889
duke@435 890 // Dead nodes in the hash table inherited from GVN were not treated as
duke@435 891 // roots during def-use info creation; hence they represent an invisible
duke@435 892 // use. Clear them out.
duke@435 893 max = _table.size();
duke@435 894 for( uint i = 0; i < max; ++i ) {
duke@435 895 Node *n = _table.at(i);
duke@435 896 if(n != NULL && n != _table.sentinel() && n->outcnt() == 0) {
duke@435 897 if( n->is_top() ) continue;
duke@435 898 assert( false, "Parse::remove_useless_nodes missed this node");
duke@435 899 hash_delete(n);
duke@435 900 }
duke@435 901 }
duke@435 902
duke@435 903 // Any Phis or Regions on the worklist probably had uses that could not
duke@435 904 // make more progress because the uses were made while the Phis and Regions
duke@435 905 // were in half-built states. Put all uses of Phis and Regions on worklist.
duke@435 906 max = _worklist.size();
duke@435 907 for( uint j = 0; j < max; j++ ) {
duke@435 908 Node *n = _worklist.at(j);
duke@435 909 uint uop = n->Opcode();
duke@435 910 if( uop == Op_Phi || uop == Op_Region ||
duke@435 911 n->is_Type() ||
duke@435 912 n->is_Mem() )
duke@435 913 add_users_to_worklist(n);
duke@435 914 }
duke@435 915 }
duke@435 916
duke@435 917
duke@435 918 #ifndef PRODUCT
duke@435 919 void PhaseIterGVN::verify_step(Node* n) {
duke@435 920 _verify_window[_verify_counter % _verify_window_size] = n;
duke@435 921 ++_verify_counter;
duke@435 922 ResourceMark rm;
duke@435 923 ResourceArea *area = Thread::current()->resource_area();
duke@435 924 VectorSet old_space(area), new_space(area);
duke@435 925 if (C->unique() < 1000 ||
duke@435 926 0 == _verify_counter % (C->unique() < 10000 ? 10 : 100)) {
duke@435 927 ++_verify_full_passes;
duke@435 928 Node::verify_recur(C->root(), -1, old_space, new_space);
duke@435 929 }
duke@435 930 const int verify_depth = 4;
duke@435 931 for ( int i = 0; i < _verify_window_size; i++ ) {
duke@435 932 Node* n = _verify_window[i];
duke@435 933 if ( n == NULL ) continue;
duke@435 934 if( n->in(0) == NodeSentinel ) { // xform_idom
duke@435 935 _verify_window[i] = n->in(1);
duke@435 936 --i; continue;
duke@435 937 }
duke@435 938 // Typical fanout is 1-2, so this call visits about 6 nodes.
duke@435 939 Node::verify_recur(n, verify_depth, old_space, new_space);
duke@435 940 }
duke@435 941 }
duke@435 942 #endif
duke@435 943
duke@435 944
duke@435 945 //------------------------------init_worklist----------------------------------
duke@435 946 // Initialize worklist for each node.
duke@435 947 void PhaseIterGVN::init_worklist( Node *n ) {
duke@435 948 if( _worklist.member(n) ) return;
duke@435 949 _worklist.push(n);
duke@435 950 uint cnt = n->req();
duke@435 951 for( uint i =0 ; i < cnt; i++ ) {
duke@435 952 Node *m = n->in(i);
duke@435 953 if( m ) init_worklist(m);
duke@435 954 }
duke@435 955 }
duke@435 956
duke@435 957 //------------------------------optimize---------------------------------------
duke@435 958 void PhaseIterGVN::optimize() {
duke@435 959 debug_only(uint num_processed = 0;);
duke@435 960 #ifndef PRODUCT
duke@435 961 {
duke@435 962 _verify_counter = 0;
duke@435 963 _verify_full_passes = 0;
duke@435 964 for ( int i = 0; i < _verify_window_size; i++ ) {
duke@435 965 _verify_window[i] = NULL;
duke@435 966 }
duke@435 967 }
duke@435 968 #endif
duke@435 969
kvn@2181 970 #ifdef ASSERT
kvn@2181 971 Node* prev = NULL;
kvn@2181 972 uint rep_cnt = 0;
kvn@2181 973 #endif
kvn@2181 974 uint loop_count = 0;
kvn@2181 975
duke@435 976 // Pull from worklist; transform node;
duke@435 977 // If node has changed: update edge info and put uses on worklist.
duke@435 978 while( _worklist.size() ) {
kvn@3154 979 if (C->check_node_count(NodeLimitFudgeFactor * 2,
kvn@3154 980 "out of nodes optimizing method")) {
kvn@3154 981 return;
kvn@3154 982 }
duke@435 983 Node *n = _worklist.pop();
kvn@5110 984 if (++loop_count >= K * C->live_nodes()) {
kvn@2181 985 debug_only(n->dump(4);)
kvn@2181 986 assert(false, "infinite loop in PhaseIterGVN::optimize");
kvn@2181 987 C->record_method_not_compilable("infinite loop in PhaseIterGVN::optimize");
kvn@2181 988 return;
kvn@2181 989 }
kvn@2181 990 #ifdef ASSERT
kvn@2181 991 if (n == prev) {
kvn@2181 992 if (++rep_cnt > 3) {
kvn@2181 993 n->dump(4);
kvn@2181 994 assert(false, "loop in Ideal transformation");
kvn@2181 995 }
kvn@2181 996 } else {
kvn@2181 997 rep_cnt = 0;
kvn@2181 998 }
kvn@2181 999 prev = n;
kvn@2181 1000 #endif
duke@435 1001 if (TraceIterativeGVN && Verbose) {
duke@435 1002 tty->print(" Pop ");
duke@435 1003 NOT_PRODUCT( n->dump(); )
duke@435 1004 debug_only(if( (num_processed++ % 100) == 0 ) _worklist.print_set();)
duke@435 1005 }
duke@435 1006
duke@435 1007 if (n->outcnt() != 0) {
duke@435 1008
duke@435 1009 #ifndef PRODUCT
duke@435 1010 uint wlsize = _worklist.size();
duke@435 1011 const Type* oldtype = type_or_null(n);
duke@435 1012 #endif //PRODUCT
duke@435 1013
duke@435 1014 Node *nn = transform_old(n);
duke@435 1015
duke@435 1016 #ifndef PRODUCT
duke@435 1017 if (TraceIterativeGVN) {
duke@435 1018 const Type* newtype = type_or_null(n);
duke@435 1019 if (nn != n) {
duke@435 1020 // print old node
duke@435 1021 tty->print("< ");
duke@435 1022 if (oldtype != newtype && oldtype != NULL) {
duke@435 1023 oldtype->dump();
duke@435 1024 }
duke@435 1025 do { tty->print("\t"); } while (tty->position() < 16);
duke@435 1026 tty->print("<");
duke@435 1027 n->dump();
duke@435 1028 }
duke@435 1029 if (oldtype != newtype || nn != n) {
duke@435 1030 // print new node and/or new type
duke@435 1031 if (oldtype == NULL) {
duke@435 1032 tty->print("* ");
duke@435 1033 } else if (nn != n) {
duke@435 1034 tty->print("> ");
duke@435 1035 } else {
duke@435 1036 tty->print("= ");
duke@435 1037 }
duke@435 1038 if (newtype == NULL) {
duke@435 1039 tty->print("null");
duke@435 1040 } else {
duke@435 1041 newtype->dump();
duke@435 1042 }
duke@435 1043 do { tty->print("\t"); } while (tty->position() < 16);
duke@435 1044 nn->dump();
duke@435 1045 }
duke@435 1046 if (Verbose && wlsize < _worklist.size()) {
duke@435 1047 tty->print(" Push {");
duke@435 1048 while (wlsize != _worklist.size()) {
duke@435 1049 Node* pushed = _worklist.at(wlsize++);
duke@435 1050 tty->print(" %d", pushed->_idx);
duke@435 1051 }
duke@435 1052 tty->print_cr(" }");
duke@435 1053 }
duke@435 1054 }
duke@435 1055 if( VerifyIterativeGVN && nn != n ) {
duke@435 1056 verify_step((Node*) NULL); // ignore n, it might be subsumed
duke@435 1057 }
duke@435 1058 #endif
duke@435 1059 } else if (!n->is_top()) {
duke@435 1060 remove_dead_node(n);
duke@435 1061 }
duke@435 1062 }
duke@435 1063
duke@435 1064 #ifndef PRODUCT
duke@435 1065 C->verify_graph_edges();
duke@435 1066 if( VerifyOpto && allow_progress() ) {
duke@435 1067 // Must turn off allow_progress to enable assert and break recursion
duke@435 1068 C->root()->verify();
duke@435 1069 { // Check if any progress was missed using IterGVN
duke@435 1070 // Def-Use info enables transformations not attempted in wash-pass
duke@435 1071 // e.g. Region/Phi cleanup, ...
duke@435 1072 // Null-check elision -- may not have reached fixpoint
duke@435 1073 // do not propagate to dominated nodes
duke@435 1074 ResourceMark rm;
duke@435 1075 PhaseIterGVN igvn2(this,"Verify"); // Fresh and clean!
duke@435 1076 // Fill worklist completely
duke@435 1077 igvn2.init_worklist(C->root());
duke@435 1078
duke@435 1079 igvn2.set_allow_progress(false);
duke@435 1080 igvn2.optimize();
duke@435 1081 igvn2.set_allow_progress(true);
duke@435 1082 }
duke@435 1083 }
duke@435 1084 if ( VerifyIterativeGVN && PrintOpto ) {
duke@435 1085 if ( _verify_counter == _verify_full_passes )
duke@435 1086 tty->print_cr("VerifyIterativeGVN: %d transforms and verify passes",
drchase@6680 1087 (int) _verify_full_passes);
duke@435 1088 else
duke@435 1089 tty->print_cr("VerifyIterativeGVN: %d transforms, %d full verify passes",
drchase@6680 1090 (int) _verify_counter, (int) _verify_full_passes);
duke@435 1091 }
duke@435 1092 #endif
duke@435 1093 }
duke@435 1094
duke@435 1095
duke@435 1096 //------------------register_new_node_with_optimizer---------------------------
duke@435 1097 // Register a new node with the optimizer. Update the types array, the def-use
duke@435 1098 // info. Put on worklist.
duke@435 1099 Node* PhaseIterGVN::register_new_node_with_optimizer(Node* n, Node* orig) {
duke@435 1100 set_type_bottom(n);
duke@435 1101 _worklist.push(n);
duke@435 1102 if (orig != NULL) C->copy_node_notes_to(n, orig);
duke@435 1103 return n;
duke@435 1104 }
duke@435 1105
duke@435 1106 //------------------------------transform--------------------------------------
duke@435 1107 // Non-recursive: idealize Node 'n' with respect to its inputs and its value
duke@435 1108 Node *PhaseIterGVN::transform( Node *n ) {
coleenp@548 1109 if (_delay_transform) {
coleenp@548 1110 // Register the node but don't optimize for now
coleenp@548 1111 register_new_node_with_optimizer(n);
coleenp@548 1112 return n;
coleenp@548 1113 }
coleenp@548 1114
duke@435 1115 // If brand new node, make space in type array, and give it a type.
duke@435 1116 ensure_type_or_null(n);
duke@435 1117 if (type_or_null(n) == NULL) {
duke@435 1118 set_type_bottom(n);
duke@435 1119 }
duke@435 1120
duke@435 1121 return transform_old(n);
duke@435 1122 }
duke@435 1123
duke@435 1124 //------------------------------transform_old----------------------------------
duke@435 1125 Node *PhaseIterGVN::transform_old( Node *n ) {
duke@435 1126 #ifndef PRODUCT
duke@435 1127 debug_only(uint loop_count = 0;);
duke@435 1128 set_transforms();
duke@435 1129 #endif
duke@435 1130 // Remove 'n' from hash table in case it gets modified
duke@435 1131 _table.hash_delete(n);
duke@435 1132 if( VerifyIterativeGVN ) {
duke@435 1133 assert( !_table.find_index(n->_idx), "found duplicate entry in table");
duke@435 1134 }
duke@435 1135
duke@435 1136 // Apply the Ideal call in a loop until it no longer applies
duke@435 1137 Node *k = n;
duke@435 1138 DEBUG_ONLY(dead_loop_check(k);)
kvn@740 1139 DEBUG_ONLY(bool is_new = (k->outcnt() == 0);)
duke@435 1140 Node *i = k->Ideal(this, /*can_reshape=*/true);
kvn@740 1141 assert(i != k || is_new || i->outcnt() > 0, "don't return dead nodes");
duke@435 1142 #ifndef PRODUCT
duke@435 1143 if( VerifyIterativeGVN )
duke@435 1144 verify_step(k);
duke@435 1145 if( i && VerifyOpto ) {
duke@435 1146 if( !allow_progress() ) {
duke@435 1147 if (i->is_Add() && i->outcnt() == 1) {
duke@435 1148 // Switched input to left side because this is the only use
duke@435 1149 } else if( i->is_If() && (i->in(0) == NULL) ) {
duke@435 1150 // This IF is dead because it is dominated by an equivalent IF When
duke@435 1151 // dominating if changed, info is not propagated sparsely to 'this'
duke@435 1152 // Propagating this info further will spuriously identify other
duke@435 1153 // progress.
duke@435 1154 return i;
duke@435 1155 } else
duke@435 1156 set_progress();
duke@435 1157 } else
duke@435 1158 set_progress();
duke@435 1159 }
duke@435 1160 #endif
duke@435 1161
duke@435 1162 while( i ) {
duke@435 1163 #ifndef PRODUCT
duke@435 1164 debug_only( if( loop_count >= K ) i->dump(4); )
duke@435 1165 assert(loop_count < K, "infinite loop in PhaseIterGVN::transform");
duke@435 1166 debug_only( loop_count++; )
duke@435 1167 #endif
duke@435 1168 assert((i->_idx >= k->_idx) || i->is_top(), "Idealize should return new nodes, use Identity to return old nodes");
duke@435 1169 // Made a change; put users of original Node on worklist
duke@435 1170 add_users_to_worklist( k );
duke@435 1171 // Replacing root of transform tree?
duke@435 1172 if( k != i ) {
duke@435 1173 // Make users of old Node now use new.
duke@435 1174 subsume_node( k, i );
duke@435 1175 k = i;
duke@435 1176 }
duke@435 1177 DEBUG_ONLY(dead_loop_check(k);)
duke@435 1178 // Try idealizing again
kvn@740 1179 DEBUG_ONLY(is_new = (k->outcnt() == 0);)
duke@435 1180 i = k->Ideal(this, /*can_reshape=*/true);
kvn@740 1181 assert(i != k || is_new || i->outcnt() > 0, "don't return dead nodes");
duke@435 1182 #ifndef PRODUCT
duke@435 1183 if( VerifyIterativeGVN )
duke@435 1184 verify_step(k);
duke@435 1185 if( i && VerifyOpto ) set_progress();
duke@435 1186 #endif
duke@435 1187 }
duke@435 1188
duke@435 1189 // If brand new node, make space in type array.
duke@435 1190 ensure_type_or_null(k);
duke@435 1191
duke@435 1192 // See what kind of values 'k' takes on at runtime
duke@435 1193 const Type *t = k->Value(this);
duke@435 1194 assert(t != NULL, "value sanity");
duke@435 1195
duke@435 1196 // Since I just called 'Value' to compute the set of run-time values
duke@435 1197 // for this Node, and 'Value' is non-local (and therefore expensive) I'll
duke@435 1198 // cache Value. Later requests for the local phase->type of this Node can
duke@435 1199 // use the cached Value instead of suffering with 'bottom_type'.
duke@435 1200 if (t != type_or_null(k)) {
duke@435 1201 NOT_PRODUCT( set_progress(); )
duke@435 1202 NOT_PRODUCT( inc_new_values();)
duke@435 1203 set_type(k, t);
duke@435 1204 // If k is a TypeNode, capture any more-precise type permanently into Node
duke@435 1205 k->raise_bottom_type(t);
duke@435 1206 // Move users of node to worklist
duke@435 1207 add_users_to_worklist( k );
duke@435 1208 }
duke@435 1209
duke@435 1210 // If 'k' computes a constant, replace it with a constant
duke@435 1211 if( t->singleton() && !k->is_Con() ) {
duke@435 1212 NOT_PRODUCT( set_progress(); )
duke@435 1213 Node *con = makecon(t); // Make a constant
duke@435 1214 add_users_to_worklist( k );
duke@435 1215 subsume_node( k, con ); // Everybody using k now uses con
duke@435 1216 return con;
duke@435 1217 }
duke@435 1218
duke@435 1219 // Now check for Identities
duke@435 1220 i = k->Identity(this); // Look for a nearby replacement
duke@435 1221 if( i != k ) { // Found? Return replacement!
duke@435 1222 NOT_PRODUCT( set_progress(); )
duke@435 1223 add_users_to_worklist( k );
duke@435 1224 subsume_node( k, i ); // Everybody using k now uses i
duke@435 1225 return i;
duke@435 1226 }
duke@435 1227
duke@435 1228 // Global Value Numbering
duke@435 1229 i = hash_find_insert(k); // Check for pre-existing node
duke@435 1230 if( i && (i != k) ) {
duke@435 1231 // Return the pre-existing node if it isn't dead
duke@435 1232 NOT_PRODUCT( set_progress(); )
duke@435 1233 add_users_to_worklist( k );
duke@435 1234 subsume_node( k, i ); // Everybody using k now uses i
duke@435 1235 return i;
duke@435 1236 }
duke@435 1237
duke@435 1238 // Return Idealized original
duke@435 1239 return k;
duke@435 1240 }
duke@435 1241
duke@435 1242 //---------------------------------saturate------------------------------------
duke@435 1243 const Type* PhaseIterGVN::saturate(const Type* new_type, const Type* old_type,
duke@435 1244 const Type* limit_type) const {
duke@435 1245 return new_type->narrow(old_type);
duke@435 1246 }
duke@435 1247
duke@435 1248 //------------------------------remove_globally_dead_node----------------------
duke@435 1249 // Kill a globally dead Node. All uses are also globally dead and are
duke@435 1250 // aggressively trimmed.
duke@435 1251 void PhaseIterGVN::remove_globally_dead_node( Node *dead ) {
dlong@3947 1252 enum DeleteProgress {
dlong@3947 1253 PROCESS_INPUTS,
dlong@3947 1254 PROCESS_OUTPUTS
dlong@3947 1255 };
dlong@3947 1256 assert(_stack.is_empty(), "not empty");
dlong@3947 1257 _stack.push(dead, PROCESS_INPUTS);
dlong@3947 1258
dlong@3947 1259 while (_stack.is_nonempty()) {
dlong@3947 1260 dead = _stack.node();
dlong@3947 1261 uint progress_state = _stack.index();
dlong@3947 1262 assert(dead != C->root(), "killing root, eh?");
dlong@3947 1263 assert(!dead->is_top(), "add check for top when pushing");
dlong@3947 1264 NOT_PRODUCT( set_progress(); )
dlong@3947 1265 if (progress_state == PROCESS_INPUTS) {
dlong@3947 1266 // After following inputs, continue to outputs
dlong@3947 1267 _stack.set_index(PROCESS_OUTPUTS);
dlong@3947 1268 if (!dead->is_Con()) { // Don't kill cons but uses
dlong@3947 1269 bool recurse = false;
dlong@3947 1270 // Remove from hash table
dlong@3947 1271 _table.hash_delete( dead );
dlong@3947 1272 // Smash all inputs to 'dead', isolating him completely
kvn@4868 1273 for (uint i = 0; i < dead->req(); i++) {
dlong@3947 1274 Node *in = dead->in(i);
kvn@4868 1275 if (in != NULL && in != C->top()) { // Points to something?
kvn@4868 1276 int nrep = dead->replace_edge(in, NULL); // Kill edges
kvn@4868 1277 assert((nrep > 0), "sanity");
kvn@4868 1278 if (in->outcnt() == 0) { // Made input go dead?
dlong@3947 1279 _stack.push(in, PROCESS_INPUTS); // Recursively remove
dlong@3947 1280 recurse = true;
dlong@3947 1281 } else if (in->outcnt() == 1 &&
dlong@3947 1282 in->has_special_unique_user()) {
dlong@3947 1283 _worklist.push(in->unique_out());
dlong@3947 1284 } else if (in->outcnt() <= 2 && dead->is_Phi()) {
kvn@4868 1285 if (in->Opcode() == Op_Region) {
dlong@3947 1286 _worklist.push(in);
kvn@4868 1287 } else if (in->is_Store()) {
dlong@3947 1288 DUIterator_Fast imax, i = in->fast_outs(imax);
dlong@3947 1289 _worklist.push(in->fast_out(i));
dlong@3947 1290 i++;
kvn@4868 1291 if (in->outcnt() == 2) {
dlong@3947 1292 _worklist.push(in->fast_out(i));
dlong@3947 1293 i++;
dlong@3947 1294 }
dlong@3947 1295 assert(!(i < imax), "sanity");
dlong@3947 1296 }
duke@435 1297 }
roland@4657 1298 if (ReduceFieldZeroing && dead->is_Load() && i == MemNode::Memory &&
roland@4657 1299 in->is_Proj() && in->in(0) != NULL && in->in(0)->is_Initialize()) {
roland@4657 1300 // A Load that directly follows an InitializeNode is
roland@4657 1301 // going away. The Stores that follow are candidates
roland@4657 1302 // again to be captured by the InitializeNode.
roland@4657 1303 for (DUIterator_Fast jmax, j = in->fast_outs(jmax); j < jmax; j++) {
roland@4657 1304 Node *n = in->fast_out(j);
roland@4657 1305 if (n->is_Store()) {
roland@4657 1306 _worklist.push(n);
roland@4657 1307 }
roland@4657 1308 }
roland@4657 1309 }
kvn@4868 1310 } // if (in != NULL && in != C->top())
kvn@4868 1311 } // for (uint i = 0; i < dead->req(); i++)
dlong@3947 1312 if (recurse) {
dlong@3947 1313 continue;
dlong@3947 1314 }
kvn@4868 1315 } // if (!dead->is_Con())
kvn@4868 1316 } // if (progress_state == PROCESS_INPUTS)
duke@435 1317
dlong@3947 1318 // Aggressively kill globally dead uses
dlong@3947 1319 // (Rather than pushing all the outs at once, we push one at a time,
dlong@3947 1320 // plus the parent to resume later, because of the indefinite number
dlong@3947 1321 // of edge deletions per loop trip.)
dlong@3947 1322 if (dead->outcnt() > 0) {
kvn@4868 1323 // Recursively remove output edges
dlong@3947 1324 _stack.push(dead->raw_out(0), PROCESS_INPUTS);
dlong@3947 1325 } else {
kvn@4868 1326 // Finished disconnecting all input and output edges.
dlong@3947 1327 _stack.pop();
kvn@4868 1328 // Remove dead node from iterative worklist
kvn@4868 1329 _worklist.remove(dead);
kvn@4868 1330 // Constant node that has no out-edges and has only one in-edge from
kvn@4868 1331 // root is usually dead. However, sometimes reshaping walk makes
kvn@4868 1332 // it reachable by adding use edges. So, we will NOT count Con nodes
kvn@4868 1333 // as dead to be conservative about the dead node count at any
kvn@4868 1334 // given time.
kvn@4868 1335 if (!dead->is_Con()) {
kvn@4868 1336 C->record_dead_node(dead->_idx);
kvn@4868 1337 }
kvn@4868 1338 if (dead->is_macro()) {
kvn@4868 1339 C->remove_macro_node(dead);
kvn@4868 1340 }
kvn@4868 1341 if (dead->is_expensive()) {
kvn@4868 1342 C->remove_expensive_node(dead);
kvn@4868 1343 }
thartmann@8476 1344 CastIINode* cast = dead->isa_CastII();
thartmann@8476 1345 if (cast != NULL && cast->has_range_check()) {
thartmann@8476 1346 C->remove_range_check_cast(cast);
thartmann@8476 1347 }
duke@435 1348 }
kvn@4868 1349 } // while (_stack.is_nonempty())
duke@435 1350 }
duke@435 1351
duke@435 1352 //------------------------------subsume_node-----------------------------------
duke@435 1353 // Remove users from node 'old' and add them to node 'nn'.
duke@435 1354 void PhaseIterGVN::subsume_node( Node *old, Node *nn ) {
duke@435 1355 assert( old != hash_find(old), "should already been removed" );
duke@435 1356 assert( old != C->top(), "cannot subsume top node");
duke@435 1357 // Copy debug or profile information to the new version:
duke@435 1358 C->copy_node_notes_to(nn, old);
duke@435 1359 // Move users of node 'old' to node 'nn'
duke@435 1360 for (DUIterator_Last imin, i = old->last_outs(imin); i >= imin; ) {
duke@435 1361 Node* use = old->last_out(i); // for each use...
duke@435 1362 // use might need re-hashing (but it won't if it's a new node)
duke@435 1363 bool is_in_table = _table.hash_delete( use );
duke@435 1364 // Update use-def info as well
duke@435 1365 // We remove all occurrences of old within use->in,
duke@435 1366 // so as to avoid rehashing any node more than once.
duke@435 1367 // The hash table probe swamps any outer loop overhead.
duke@435 1368 uint num_edges = 0;
duke@435 1369 for (uint jmax = use->len(), j = 0; j < jmax; j++) {
duke@435 1370 if (use->in(j) == old) {
duke@435 1371 use->set_req(j, nn);
duke@435 1372 ++num_edges;
duke@435 1373 }
duke@435 1374 }
duke@435 1375 // Insert into GVN hash table if unique
duke@435 1376 // If a duplicate, 'use' will be cleaned up when pulled off worklist
duke@435 1377 if( is_in_table ) {
duke@435 1378 hash_find_insert(use);
duke@435 1379 }
duke@435 1380 i -= num_edges; // we deleted 1 or more copies of this edge
duke@435 1381 }
duke@435 1382
poonam@8945 1383 // Search for instance field data PhiNodes in the same region pointing to the old
poonam@8945 1384 // memory PhiNode and update their instance memory ids to point to the new node.
poonam@8945 1385 if (old->is_Phi() && old->as_Phi()->type()->has_memory() && old->in(0) != NULL) {
poonam@8945 1386 Node* region = old->in(0);
poonam@8945 1387 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
poonam@8945 1388 PhiNode* phi = region->fast_out(i)->isa_Phi();
poonam@8945 1389 if (phi != NULL && phi->inst_mem_id() == (int)old->_idx) {
poonam@8945 1390 phi->set_inst_mem_id((int)nn->_idx);
poonam@8945 1391 }
poonam@8945 1392 }
poonam@8945 1393 }
poonam@8945 1394
duke@435 1395 // Smash all inputs to 'old', isolating him completely
kvn@4115 1396 Node *temp = new (C) Node(1);
duke@435 1397 temp->init_req(0,nn); // Add a use to nn to prevent him from dying
duke@435 1398 remove_dead_node( old );
duke@435 1399 temp->del_req(0); // Yank bogus edge
duke@435 1400 #ifndef PRODUCT
duke@435 1401 if( VerifyIterativeGVN ) {
duke@435 1402 for ( int i = 0; i < _verify_window_size; i++ ) {
duke@435 1403 if ( _verify_window[i] == old )
duke@435 1404 _verify_window[i] = nn;
duke@435 1405 }
duke@435 1406 }
duke@435 1407 #endif
duke@435 1408 _worklist.remove(temp); // this can be necessary
duke@435 1409 temp->destruct(); // reuse the _idx of this little guy
duke@435 1410 }
duke@435 1411
duke@435 1412 //------------------------------add_users_to_worklist--------------------------
duke@435 1413 void PhaseIterGVN::add_users_to_worklist0( Node *n ) {
duke@435 1414 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
duke@435 1415 _worklist.push(n->fast_out(i)); // Push on worklist
duke@435 1416 }
duke@435 1417 }
duke@435 1418
shshahma@8893 1419 // Return counted loop Phi if as a counted loop exit condition, cmp
shshahma@8893 1420 // compares the the induction variable with n
shshahma@8893 1421 static PhiNode* countedloop_phi_from_cmp(CmpINode* cmp, Node* n) {
shshahma@8893 1422 for (DUIterator_Fast imax, i = cmp->fast_outs(imax); i < imax; i++) {
shshahma@8893 1423 Node* bol = cmp->fast_out(i);
shshahma@8893 1424 for (DUIterator_Fast i2max, i2 = bol->fast_outs(i2max); i2 < i2max; i2++) {
shshahma@8893 1425 Node* iff = bol->fast_out(i2);
shshahma@8893 1426 if (iff->is_CountedLoopEnd()) {
shshahma@8893 1427 CountedLoopEndNode* cle = iff->as_CountedLoopEnd();
shshahma@8893 1428 if (cle->limit() == n) {
shshahma@8893 1429 PhiNode* phi = cle->phi();
shshahma@8893 1430 if (phi != NULL) {
shshahma@8893 1431 return phi;
shshahma@8893 1432 }
shshahma@8893 1433 }
shshahma@8893 1434 }
shshahma@8893 1435 }
shshahma@8893 1436 }
shshahma@8893 1437 return NULL;
shshahma@8893 1438 }
shshahma@8893 1439
duke@435 1440 void PhaseIterGVN::add_users_to_worklist( Node *n ) {
duke@435 1441 add_users_to_worklist0(n);
duke@435 1442
duke@435 1443 // Move users of node to worklist
duke@435 1444 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
duke@435 1445 Node* use = n->fast_out(i); // Get use
duke@435 1446
duke@435 1447 if( use->is_Multi() || // Multi-definer? Push projs on worklist
duke@435 1448 use->is_Store() ) // Enable store/load same address
duke@435 1449 add_users_to_worklist0(use);
duke@435 1450
duke@435 1451 // If we changed the receiver type to a call, we need to revisit
duke@435 1452 // the Catch following the call. It's looking for a non-NULL
duke@435 1453 // receiver to know when to enable the regular fall-through path
duke@435 1454 // in addition to the NullPtrException path.
duke@435 1455 if (use->is_CallDynamicJava() && n == use->in(TypeFunc::Parms)) {
duke@435 1456 Node* p = use->as_CallDynamicJava()->proj_out(TypeFunc::Control);
duke@435 1457 if (p != NULL) {
duke@435 1458 add_users_to_worklist0(p);
duke@435 1459 }
duke@435 1460 }
duke@435 1461
roland@7394 1462 uint use_op = use->Opcode();
roland@7394 1463 if(use->is_Cmp()) { // Enable CMP/BOOL optimization
duke@435 1464 add_users_to_worklist(use); // Put Bool on worklist
duke@435 1465 if (use->outcnt() > 0) {
duke@435 1466 Node* bol = use->raw_out(0);
duke@435 1467 if (bol->outcnt() > 0) {
duke@435 1468 Node* iff = bol->raw_out(0);
shshahma@8893 1469 if (iff->outcnt() == 2) {
roland@7394 1470 // Look for the 'is_x2logic' pattern: "x ? : 0 : 1" and put the
roland@7394 1471 // phi merging either 0 or 1 onto the worklist
duke@435 1472 Node* ifproj0 = iff->raw_out(0);
duke@435 1473 Node* ifproj1 = iff->raw_out(1);
duke@435 1474 if (ifproj0->outcnt() > 0 && ifproj1->outcnt() > 0) {
duke@435 1475 Node* region0 = ifproj0->raw_out(0);
duke@435 1476 Node* region1 = ifproj1->raw_out(0);
duke@435 1477 if( region0 == region1 )
duke@435 1478 add_users_to_worklist0(region0);
duke@435 1479 }
duke@435 1480 }
duke@435 1481 }
duke@435 1482 }
roland@7394 1483 if (use_op == Op_CmpI) {
shshahma@8893 1484 Node* phi = countedloop_phi_from_cmp((CmpINode*)use, n);
shshahma@8893 1485 if (phi != NULL) {
shshahma@8893 1486 // If an opaque node feeds into the limit condition of a
shshahma@8893 1487 // CountedLoop, we need to process the Phi node for the
shshahma@8893 1488 // induction variable when the opaque node is removed:
shshahma@8893 1489 // the range of values taken by the Phi is now known and
shshahma@8893 1490 // so its type is also known.
shshahma@8893 1491 _worklist.push(phi);
shshahma@8893 1492 }
roland@7394 1493 Node* in1 = use->in(1);
roland@7394 1494 for (uint i = 0; i < in1->outcnt(); i++) {
roland@7394 1495 if (in1->raw_out(i)->Opcode() == Op_CastII) {
roland@7394 1496 Node* castii = in1->raw_out(i);
roland@7394 1497 if (castii->in(0) != NULL && castii->in(0)->in(0) != NULL && castii->in(0)->in(0)->is_If()) {
roland@7394 1498 Node* ifnode = castii->in(0)->in(0);
roland@7395 1499 if (ifnode->in(1) != NULL && ifnode->in(1)->is_Bool() && ifnode->in(1)->in(1) == use) {
roland@7394 1500 // Reprocess a CastII node that may depend on an
roland@7394 1501 // opaque node value when the opaque node is
roland@7394 1502 // removed. In case it carries a dependency we can do
roland@7394 1503 // a better job of computing its type.
roland@7394 1504 _worklist.push(castii);
roland@7394 1505 }
roland@7394 1506 }
roland@7394 1507 }
roland@7394 1508 }
roland@7394 1509 }
duke@435 1510 }
duke@435 1511
duke@435 1512 // If changed Cast input, check Phi users for simple cycles
kvn@500 1513 if( use->is_ConstraintCast() || use->is_CheckCastPP() ) {
duke@435 1514 for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
duke@435 1515 Node* u = use->fast_out(i2);
duke@435 1516 if (u->is_Phi())
duke@435 1517 _worklist.push(u);
duke@435 1518 }
duke@435 1519 }
duke@435 1520 // If changed LShift inputs, check RShift users for useless sign-ext
duke@435 1521 if( use_op == Op_LShiftI ) {
duke@435 1522 for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
duke@435 1523 Node* u = use->fast_out(i2);
duke@435 1524 if (u->Opcode() == Op_RShiftI)
duke@435 1525 _worklist.push(u);
duke@435 1526 }
duke@435 1527 }
kvn@6679 1528 // If changed AddI/SubI inputs, check CmpU for range check optimization.
kvn@6679 1529 if (use_op == Op_AddI || use_op == Op_SubI) {
kvn@6679 1530 for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
kvn@6679 1531 Node* u = use->fast_out(i2);
kvn@6679 1532 if (u->is_Cmp() && (u->Opcode() == Op_CmpU)) {
kvn@6679 1533 _worklist.push(u);
kvn@6679 1534 }
kvn@6679 1535 }
kvn@6679 1536 }
duke@435 1537 // If changed AddP inputs, check Stores for loop invariant
duke@435 1538 if( use_op == Op_AddP ) {
duke@435 1539 for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
duke@435 1540 Node* u = use->fast_out(i2);
duke@435 1541 if (u->is_Mem())
duke@435 1542 _worklist.push(u);
duke@435 1543 }
duke@435 1544 }
duke@435 1545 // If changed initialization activity, check dependent Stores
duke@435 1546 if (use_op == Op_Allocate || use_op == Op_AllocateArray) {
duke@435 1547 InitializeNode* init = use->as_Allocate()->initialization();
duke@435 1548 if (init != NULL) {
duke@435 1549 Node* imem = init->proj_out(TypeFunc::Memory);
duke@435 1550 if (imem != NULL) add_users_to_worklist0(imem);
duke@435 1551 }
duke@435 1552 }
duke@435 1553 if (use_op == Op_Initialize) {
duke@435 1554 Node* imem = use->as_Initialize()->proj_out(TypeFunc::Memory);
duke@435 1555 if (imem != NULL) add_users_to_worklist0(imem);
duke@435 1556 }
duke@435 1557 }
duke@435 1558 }
duke@435 1559
roland@5991 1560 /**
roland@5991 1561 * Remove the speculative part of all types that we know of
roland@5991 1562 */
roland@5991 1563 void PhaseIterGVN::remove_speculative_types() {
roland@5991 1564 assert(UseTypeSpeculation, "speculation is off");
roland@5991 1565 for (uint i = 0; i < _types.Size(); i++) {
roland@5991 1566 const Type* t = _types.fast_lookup(i);
roland@6313 1567 if (t != NULL) {
roland@6313 1568 _types.map(i, t->remove_speculative());
roland@5991 1569 }
roland@5991 1570 }
roland@6313 1571 _table.check_no_speculative_types();
roland@5991 1572 }
roland@5991 1573
duke@435 1574 //=============================================================================
duke@435 1575 #ifndef PRODUCT
duke@435 1576 uint PhaseCCP::_total_invokes = 0;
duke@435 1577 uint PhaseCCP::_total_constants = 0;
duke@435 1578 #endif
duke@435 1579 //------------------------------PhaseCCP---------------------------------------
duke@435 1580 // Conditional Constant Propagation, ala Wegman & Zadeck
duke@435 1581 PhaseCCP::PhaseCCP( PhaseIterGVN *igvn ) : PhaseIterGVN(igvn) {
duke@435 1582 NOT_PRODUCT( clear_constants(); )
duke@435 1583 assert( _worklist.size() == 0, "" );
duke@435 1584 // Clear out _nodes from IterGVN. Must be clear to transform call.
duke@435 1585 _nodes.clear(); // Clear out from IterGVN
duke@435 1586 analyze();
duke@435 1587 }
duke@435 1588
duke@435 1589 #ifndef PRODUCT
duke@435 1590 //------------------------------~PhaseCCP--------------------------------------
duke@435 1591 PhaseCCP::~PhaseCCP() {
duke@435 1592 inc_invokes();
duke@435 1593 _total_constants += count_constants();
duke@435 1594 }
duke@435 1595 #endif
duke@435 1596
duke@435 1597
duke@435 1598 #ifdef ASSERT
duke@435 1599 static bool ccp_type_widens(const Type* t, const Type* t0) {
duke@435 1600 assert(t->meet(t0) == t, "Not monotonic");
duke@435 1601 switch (t->base() == t0->base() ? t->base() : Type::Top) {
duke@435 1602 case Type::Int:
duke@435 1603 assert(t0->isa_int()->_widen <= t->isa_int()->_widen, "widen increases");
duke@435 1604 break;
duke@435 1605 case Type::Long:
duke@435 1606 assert(t0->isa_long()->_widen <= t->isa_long()->_widen, "widen increases");
duke@435 1607 break;
duke@435 1608 }
duke@435 1609 return true;
duke@435 1610 }
duke@435 1611 #endif //ASSERT
duke@435 1612
duke@435 1613 //------------------------------analyze----------------------------------------
duke@435 1614 void PhaseCCP::analyze() {
duke@435 1615 // Initialize all types to TOP, optimistic analysis
duke@435 1616 for (int i = C->unique() - 1; i >= 0; i--) {
duke@435 1617 _types.map(i,Type::TOP);
duke@435 1618 }
duke@435 1619
duke@435 1620 // Push root onto worklist
duke@435 1621 Unique_Node_List worklist;
duke@435 1622 worklist.push(C->root());
duke@435 1623
duke@435 1624 // Pull from worklist; compute new value; push changes out.
duke@435 1625 // This loop is the meat of CCP.
duke@435 1626 while( worklist.size() ) {
duke@435 1627 Node *n = worklist.pop();
duke@435 1628 const Type *t = n->Value(this);
duke@435 1629 if (t != type(n)) {
duke@435 1630 assert(ccp_type_widens(t, type(n)), "ccp type must widen");
duke@435 1631 #ifndef PRODUCT
duke@435 1632 if( TracePhaseCCP ) {
duke@435 1633 t->dump();
duke@435 1634 do { tty->print("\t"); } while (tty->position() < 16);
duke@435 1635 n->dump();
duke@435 1636 }
duke@435 1637 #endif
duke@435 1638 set_type(n, t);
duke@435 1639 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
duke@435 1640 Node* m = n->fast_out(i); // Get user
aeriksso@7847 1641 if (m->is_Region()) { // New path to Region? Must recheck Phis too
duke@435 1642 for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
duke@435 1643 Node* p = m->fast_out(i2); // Propagate changes to uses
aeriksso@7847 1644 if (p->bottom_type() != type(p)) { // If not already bottomed out
duke@435 1645 worklist.push(p); // Propagate change to user
aeriksso@7847 1646 }
duke@435 1647 }
duke@435 1648 }
twisti@1040 1649 // If we changed the receiver type to a call, we need to revisit
duke@435 1650 // the Catch following the call. It's looking for a non-NULL
duke@435 1651 // receiver to know when to enable the regular fall-through path
duke@435 1652 // in addition to the NullPtrException path
duke@435 1653 if (m->is_Call()) {
duke@435 1654 for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
duke@435 1655 Node* p = m->fast_out(i2); // Propagate changes to uses
aeriksso@7847 1656 if (p->is_Proj() && p->as_Proj()->_con == TypeFunc::Control && p->outcnt() == 1) {
duke@435 1657 worklist.push(p->unique_out());
aeriksso@7847 1658 }
duke@435 1659 }
duke@435 1660 }
aeriksso@7847 1661 if (m->bottom_type() != type(m)) { // If not already bottomed out
duke@435 1662 worklist.push(m); // Propagate change to user
aeriksso@7847 1663 }
aeriksso@7847 1664
aeriksso@7847 1665 // CmpU nodes can get their type information from two nodes up in the
aeriksso@7847 1666 // graph (instead of from the nodes immediately above). Make sure they
aeriksso@7847 1667 // are added to the worklist if nodes they depend on are updated, since
aeriksso@7847 1668 // they could be missed and get wrong types otherwise.
aeriksso@7847 1669 uint m_op = m->Opcode();
aeriksso@7847 1670 if (m_op == Op_AddI || m_op == Op_SubI) {
aeriksso@7847 1671 for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
aeriksso@7847 1672 Node* p = m->fast_out(i2); // Propagate changes to uses
aeriksso@7847 1673 if (p->Opcode() == Op_CmpU) {
aeriksso@7847 1674 // Got a CmpU which might need the new type information from node n.
aeriksso@7847 1675 if(p->bottom_type() != type(p)) { // If not already bottomed out
aeriksso@7847 1676 worklist.push(p); // Propagate change to user
aeriksso@7847 1677 }
aeriksso@7847 1678 }
aeriksso@7847 1679 }
aeriksso@7847 1680 }
shshahma@8893 1681 // If n is used in a counted loop exit condition then the type
shshahma@8893 1682 // of the counted loop's Phi depends on the type of n. See
shshahma@8893 1683 // PhiNode::Value().
shshahma@8893 1684 if (m_op == Op_CmpI) {
shshahma@8893 1685 PhiNode* phi = countedloop_phi_from_cmp((CmpINode*)m, n);
shshahma@8893 1686 if (phi != NULL) {
shshahma@8893 1687 worklist.push(phi);
shshahma@8893 1688 }
shshahma@8893 1689 }
duke@435 1690 }
duke@435 1691 }
duke@435 1692 }
duke@435 1693 }
duke@435 1694
duke@435 1695 //------------------------------do_transform-----------------------------------
duke@435 1696 // Top level driver for the recursive transformer
duke@435 1697 void PhaseCCP::do_transform() {
duke@435 1698 // Correct leaves of new-space Nodes; they point to old-space.
duke@435 1699 C->set_root( transform(C->root())->as_Root() );
duke@435 1700 assert( C->top(), "missing TOP node" );
duke@435 1701 assert( C->root(), "missing root" );
duke@435 1702 }
duke@435 1703
duke@435 1704 //------------------------------transform--------------------------------------
duke@435 1705 // Given a Node in old-space, clone him into new-space.
duke@435 1706 // Convert any of his old-space children into new-space children.
duke@435 1707 Node *PhaseCCP::transform( Node *n ) {
duke@435 1708 Node *new_node = _nodes[n->_idx]; // Check for transformed node
duke@435 1709 if( new_node != NULL )
duke@435 1710 return new_node; // Been there, done that, return old answer
duke@435 1711 new_node = transform_once(n); // Check for constant
duke@435 1712 _nodes.map( n->_idx, new_node ); // Flag as having been cloned
duke@435 1713
duke@435 1714 // Allocate stack of size _nodes.Size()/2 to avoid frequent realloc
zmajo@8068 1715 GrowableArray <Node *> trstack(C->live_nodes() >> 1);
duke@435 1716
duke@435 1717 trstack.push(new_node); // Process children of cloned node
duke@435 1718 while ( trstack.is_nonempty() ) {
duke@435 1719 Node *clone = trstack.pop();
duke@435 1720 uint cnt = clone->req();
duke@435 1721 for( uint i = 0; i < cnt; i++ ) { // For all inputs do
duke@435 1722 Node *input = clone->in(i);
duke@435 1723 if( input != NULL ) { // Ignore NULLs
duke@435 1724 Node *new_input = _nodes[input->_idx]; // Check for cloned input node
duke@435 1725 if( new_input == NULL ) {
duke@435 1726 new_input = transform_once(input); // Check for constant
duke@435 1727 _nodes.map( input->_idx, new_input );// Flag as having been cloned
duke@435 1728 trstack.push(new_input);
duke@435 1729 }
duke@435 1730 assert( new_input == clone->in(i), "insanity check");
duke@435 1731 }
duke@435 1732 }
duke@435 1733 }
duke@435 1734 return new_node;
duke@435 1735 }
duke@435 1736
duke@435 1737
duke@435 1738 //------------------------------transform_once---------------------------------
duke@435 1739 // For PhaseCCP, transformation is IDENTITY unless Node computed a constant.
duke@435 1740 Node *PhaseCCP::transform_once( Node *n ) {
duke@435 1741 const Type *t = type(n);
duke@435 1742 // Constant? Use constant Node instead
duke@435 1743 if( t->singleton() ) {
duke@435 1744 Node *nn = n; // Default is to return the original constant
duke@435 1745 if( t == Type::TOP ) {
duke@435 1746 // cache my top node on the Compile instance
duke@435 1747 if( C->cached_top_node() == NULL || C->cached_top_node()->in(0) == NULL ) {
duke@435 1748 C->set_cached_top_node( ConNode::make(C, Type::TOP) );
duke@435 1749 set_type(C->top(), Type::TOP);
duke@435 1750 }
duke@435 1751 nn = C->top();
duke@435 1752 }
duke@435 1753 if( !n->is_Con() ) {
duke@435 1754 if( t != Type::TOP ) {
duke@435 1755 nn = makecon(t); // ConNode::make(t);
duke@435 1756 NOT_PRODUCT( inc_constants(); )
duke@435 1757 } else if( n->is_Region() ) { // Unreachable region
duke@435 1758 // Note: nn == C->top()
duke@435 1759 n->set_req(0, NULL); // Cut selfreference
duke@435 1760 // Eagerly remove dead phis to avoid phis copies creation.
duke@435 1761 for (DUIterator i = n->outs(); n->has_out(i); i++) {
duke@435 1762 Node* m = n->out(i);
duke@435 1763 if( m->is_Phi() ) {
duke@435 1764 assert(type(m) == Type::TOP, "Unreachable region should not have live phis.");
kvn@1976 1765 replace_node(m, nn);
duke@435 1766 --i; // deleted this phi; rescan starting with next position
duke@435 1767 }
duke@435 1768 }
duke@435 1769 }
kvn@1976 1770 replace_node(n,nn); // Update DefUse edges for new constant
duke@435 1771 }
duke@435 1772 return nn;
duke@435 1773 }
duke@435 1774
duke@435 1775 // If x is a TypeNode, capture any more-precise type permanently into Node
duke@435 1776 if (t != n->bottom_type()) {
duke@435 1777 hash_delete(n); // changing bottom type may force a rehash
duke@435 1778 n->raise_bottom_type(t);
duke@435 1779 _worklist.push(n); // n re-enters the hash table via the worklist
duke@435 1780 }
duke@435 1781
duke@435 1782 // Idealize graph using DU info. Must clone() into new-space.
duke@435 1783 // DU info is generally used to show profitability, progress or safety
duke@435 1784 // (but generally not needed for correctness).
duke@435 1785 Node *nn = n->Ideal_DU_postCCP(this);
duke@435 1786
duke@435 1787 // TEMPORARY fix to ensure that 2nd GVN pass eliminates NULL checks
duke@435 1788 switch( n->Opcode() ) {
duke@435 1789 case Op_FastLock: // Revisit FastLocks for lock coarsening
duke@435 1790 case Op_If:
duke@435 1791 case Op_CountedLoopEnd:
duke@435 1792 case Op_Region:
duke@435 1793 case Op_Loop:
duke@435 1794 case Op_CountedLoop:
duke@435 1795 case Op_Conv2B:
duke@435 1796 case Op_Opaque1:
duke@435 1797 case Op_Opaque2:
duke@435 1798 _worklist.push(n);
duke@435 1799 break;
duke@435 1800 default:
duke@435 1801 break;
duke@435 1802 }
duke@435 1803 if( nn ) {
duke@435 1804 _worklist.push(n);
duke@435 1805 // Put users of 'n' onto worklist for second igvn transform
duke@435 1806 add_users_to_worklist(n);
duke@435 1807 return nn;
duke@435 1808 }
duke@435 1809
duke@435 1810 return n;
duke@435 1811 }
duke@435 1812
duke@435 1813 //---------------------------------saturate------------------------------------
duke@435 1814 const Type* PhaseCCP::saturate(const Type* new_type, const Type* old_type,
duke@435 1815 const Type* limit_type) const {
never@1444 1816 const Type* wide_type = new_type->widen(old_type, limit_type);
duke@435 1817 if (wide_type != new_type) { // did we widen?
duke@435 1818 // If so, we may have widened beyond the limit type. Clip it back down.
duke@435 1819 new_type = wide_type->filter(limit_type);
duke@435 1820 }
duke@435 1821 return new_type;
duke@435 1822 }
duke@435 1823
duke@435 1824 //------------------------------print_statistics-------------------------------
duke@435 1825 #ifndef PRODUCT
duke@435 1826 void PhaseCCP::print_statistics() {
duke@435 1827 tty->print_cr("CCP: %d constants found: %d", _total_invokes, _total_constants);
duke@435 1828 }
duke@435 1829 #endif
duke@435 1830
duke@435 1831
duke@435 1832 //=============================================================================
duke@435 1833 #ifndef PRODUCT
duke@435 1834 uint PhasePeephole::_total_peepholes = 0;
duke@435 1835 #endif
duke@435 1836 //------------------------------PhasePeephole----------------------------------
duke@435 1837 // Conditional Constant Propagation, ala Wegman & Zadeck
duke@435 1838 PhasePeephole::PhasePeephole( PhaseRegAlloc *regalloc, PhaseCFG &cfg )
duke@435 1839 : PhaseTransform(Peephole), _regalloc(regalloc), _cfg(cfg) {
duke@435 1840 NOT_PRODUCT( clear_peepholes(); )
duke@435 1841 }
duke@435 1842
duke@435 1843 #ifndef PRODUCT
duke@435 1844 //------------------------------~PhasePeephole---------------------------------
duke@435 1845 PhasePeephole::~PhasePeephole() {
duke@435 1846 _total_peepholes += count_peepholes();
duke@435 1847 }
duke@435 1848 #endif
duke@435 1849
duke@435 1850 //------------------------------transform--------------------------------------
duke@435 1851 Node *PhasePeephole::transform( Node *n ) {
duke@435 1852 ShouldNotCallThis();
duke@435 1853 return NULL;
duke@435 1854 }
duke@435 1855
duke@435 1856 //------------------------------do_transform-----------------------------------
duke@435 1857 void PhasePeephole::do_transform() {
duke@435 1858 bool method_name_not_printed = true;
duke@435 1859
duke@435 1860 // Examine each basic block
adlertz@5539 1861 for (uint block_number = 1; block_number < _cfg.number_of_blocks(); ++block_number) {
adlertz@5539 1862 Block* block = _cfg.get_block(block_number);
duke@435 1863 bool block_not_printed = true;
duke@435 1864
duke@435 1865 // and each instruction within a block
adlertz@5635 1866 uint end_index = block->number_of_nodes();
duke@435 1867 // block->end_idx() not valid after PhaseRegAlloc
duke@435 1868 for( uint instruction_index = 1; instruction_index < end_index; ++instruction_index ) {
adlertz@5635 1869 Node *n = block->get_node(instruction_index);
duke@435 1870 if( n->is_Mach() ) {
duke@435 1871 MachNode *m = n->as_Mach();
duke@435 1872 int deleted_count = 0;
duke@435 1873 // check for peephole opportunities
duke@435 1874 MachNode *m2 = m->peephole( block, instruction_index, _regalloc, deleted_count, C );
duke@435 1875 if( m2 != NULL ) {
duke@435 1876 #ifndef PRODUCT
duke@435 1877 if( PrintOptoPeephole ) {
duke@435 1878 // Print method, first time only
duke@435 1879 if( C->method() && method_name_not_printed ) {
duke@435 1880 C->method()->print_short_name(); tty->cr();
duke@435 1881 method_name_not_printed = false;
duke@435 1882 }
duke@435 1883 // Print this block
duke@435 1884 if( Verbose && block_not_printed) {
duke@435 1885 tty->print_cr("in block");
duke@435 1886 block->dump();
duke@435 1887 block_not_printed = false;
duke@435 1888 }
duke@435 1889 // Print instructions being deleted
duke@435 1890 for( int i = (deleted_count - 1); i >= 0; --i ) {
adlertz@5635 1891 block->get_node(instruction_index-i)->as_Mach()->format(_regalloc); tty->cr();
duke@435 1892 }
duke@435 1893 tty->print_cr("replaced with");
duke@435 1894 // Print new instruction
duke@435 1895 m2->format(_regalloc);
duke@435 1896 tty->print("\n\n");
duke@435 1897 }
duke@435 1898 #endif
duke@435 1899 // Remove old nodes from basic block and update instruction_index
duke@435 1900 // (old nodes still exist and may have edges pointing to them
duke@435 1901 // as register allocation info is stored in the allocator using
duke@435 1902 // the node index to live range mappings.)
duke@435 1903 uint safe_instruction_index = (instruction_index - deleted_count);
duke@435 1904 for( ; (instruction_index > safe_instruction_index); --instruction_index ) {
adlertz@5635 1905 block->remove_node( instruction_index );
duke@435 1906 }
duke@435 1907 // install new node after safe_instruction_index
adlertz@5635 1908 block->insert_node(m2, safe_instruction_index + 1);
adlertz@5635 1909 end_index = block->number_of_nodes() - 1; // Recompute new block size
duke@435 1910 NOT_PRODUCT( inc_peepholes(); )
duke@435 1911 }
duke@435 1912 }
duke@435 1913 }
duke@435 1914 }
duke@435 1915 }
duke@435 1916
duke@435 1917 //------------------------------print_statistics-------------------------------
duke@435 1918 #ifndef PRODUCT
duke@435 1919 void PhasePeephole::print_statistics() {
duke@435 1920 tty->print_cr("Peephole: peephole rules applied: %d", _total_peepholes);
duke@435 1921 }
duke@435 1922 #endif
duke@435 1923
duke@435 1924
duke@435 1925 //=============================================================================
duke@435 1926 //------------------------------set_req_X--------------------------------------
duke@435 1927 void Node::set_req_X( uint i, Node *n, PhaseIterGVN *igvn ) {
duke@435 1928 assert( is_not_dead(n), "can not use dead node");
duke@435 1929 assert( igvn->hash_find(this) != this, "Need to remove from hash before changing edges" );
duke@435 1930 Node *old = in(i);
duke@435 1931 set_req(i, n);
duke@435 1932
duke@435 1933 // old goes dead?
duke@435 1934 if( old ) {
duke@435 1935 switch (old->outcnt()) {
cfang@1362 1936 case 0:
cfang@1362 1937 // Put into the worklist to kill later. We do not kill it now because the
cfang@1362 1938 // recursive kill will delete the current node (this) if dead-loop exists
duke@435 1939 if (!old->is_top())
cfang@1362 1940 igvn->_worklist.push( old );
duke@435 1941 break;
duke@435 1942 case 1:
duke@435 1943 if( old->is_Store() || old->has_special_unique_user() )
duke@435 1944 igvn->add_users_to_worklist( old );
duke@435 1945 break;
duke@435 1946 case 2:
duke@435 1947 if( old->is_Store() )
duke@435 1948 igvn->add_users_to_worklist( old );
duke@435 1949 if( old->Opcode() == Op_Region )
duke@435 1950 igvn->_worklist.push(old);
duke@435 1951 break;
duke@435 1952 case 3:
duke@435 1953 if( old->Opcode() == Op_Region ) {
duke@435 1954 igvn->_worklist.push(old);
duke@435 1955 igvn->add_users_to_worklist( old );
duke@435 1956 }
duke@435 1957 break;
duke@435 1958 default:
duke@435 1959 break;
duke@435 1960 }
duke@435 1961 }
duke@435 1962
duke@435 1963 }
duke@435 1964
duke@435 1965 //-------------------------------replace_by-----------------------------------
duke@435 1966 // Using def-use info, replace one node for another. Follow the def-use info
duke@435 1967 // to all users of the OLD node. Then make all uses point to the NEW node.
duke@435 1968 void Node::replace_by(Node *new_node) {
duke@435 1969 assert(!is_top(), "top node has no DU info");
duke@435 1970 for (DUIterator_Last imin, i = last_outs(imin); i >= imin; ) {
duke@435 1971 Node* use = last_out(i);
duke@435 1972 uint uses_found = 0;
duke@435 1973 for (uint j = 0; j < use->len(); j++) {
duke@435 1974 if (use->in(j) == this) {
duke@435 1975 if (j < use->req())
duke@435 1976 use->set_req(j, new_node);
duke@435 1977 else use->set_prec(j, new_node);
duke@435 1978 uses_found++;
duke@435 1979 }
duke@435 1980 }
duke@435 1981 i -= uses_found; // we deleted 1 or more copies of this edge
duke@435 1982 }
duke@435 1983 }
duke@435 1984
duke@435 1985 //=============================================================================
duke@435 1986 //-----------------------------------------------------------------------------
duke@435 1987 void Type_Array::grow( uint i ) {
duke@435 1988 if( !_max ) {
duke@435 1989 _max = 1;
duke@435 1990 _types = (const Type**)_a->Amalloc( _max * sizeof(Type*) );
duke@435 1991 _types[0] = NULL;
duke@435 1992 }
duke@435 1993 uint old = _max;
duke@435 1994 while( i >= _max ) _max <<= 1; // Double to fit
duke@435 1995 _types = (const Type**)_a->Arealloc( _types, old*sizeof(Type*),_max*sizeof(Type*));
duke@435 1996 memset( &_types[old], 0, (_max-old)*sizeof(Type*) );
duke@435 1997 }
duke@435 1998
duke@435 1999 //------------------------------dump-------------------------------------------
duke@435 2000 #ifndef PRODUCT
duke@435 2001 void Type_Array::dump() const {
duke@435 2002 uint max = Size();
duke@435 2003 for( uint i = 0; i < max; i++ ) {
duke@435 2004 if( _types[i] != NULL ) {
duke@435 2005 tty->print(" %d\t== ", i); _types[i]->dump(); tty->cr();
duke@435 2006 }
duke@435 2007 }
duke@435 2008 }
duke@435 2009 #endif

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