1 /* 2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "libadt/vectset.hpp" 27 #include "memory/allocation.inline.hpp" 28 #include "opto/cfgnode.hpp" 29 #include "opto/connode.hpp" 30 #include "opto/loopnode.hpp" 31 #include "opto/machnode.hpp" 32 #include "opto/matcher.hpp" 33 #include "opto/node.hpp" 34 #include "opto/opcodes.hpp" 35 #include "opto/regmask.hpp" 36 #include "opto/type.hpp" 37 #include "utilities/copy.hpp" 38 39 class RegMask; 40 // #include "phase.hpp" 41 class PhaseTransform; 42 class PhaseGVN; 43 44 // Arena we are currently building Nodes in 45 const uint Node::NotAMachineReg = 0xffff0000; 46 47 #ifndef PRODUCT 48 extern int nodes_created; 49 #endif 50 51 #ifdef ASSERT 52 53 //-------------------------- construct_node------------------------------------ 54 // Set a breakpoint here to identify where a particular node index is built. 55 void Node::verify_construction() { 56 _debug_orig = NULL; 57 int old_debug_idx = Compile::debug_idx(); 58 int new_debug_idx = old_debug_idx+1; 59 if (new_debug_idx > 0) { 60 // Arrange that the lowest five decimal digits of _debug_idx 61 // will repeat those of _idx. In case this is somehow pathological, 62 // we continue to assign negative numbers (!) consecutively. 63 const int mod = 100000; 64 int bump = (int)(_idx - new_debug_idx) % mod; 65 if (bump < 0) bump += mod; 66 assert(bump >= 0 && bump < mod, ""); 67 new_debug_idx += bump; 68 } 69 Compile::set_debug_idx(new_debug_idx); 70 set_debug_idx( new_debug_idx ); 71 assert(Compile::current()->unique() < (INT_MAX - 1), "Node limit exceeded INT_MAX"); 72 assert(Compile::current()->live_nodes() < (uint)MaxNodeLimit, "Live Node limit exceeded limit"); 73 if (BreakAtNode != 0 && (_debug_idx == BreakAtNode || (int)_idx == BreakAtNode)) { 74 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=%d", _idx, _debug_idx); 75 BREAKPOINT; 76 } 77 #if OPTO_DU_ITERATOR_ASSERT 78 _last_del = NULL; 79 _del_tick = 0; 80 #endif 81 _hash_lock = 0; 82 } 83 84 85 // #ifdef ASSERT ... 86 87 #if OPTO_DU_ITERATOR_ASSERT 88 void DUIterator_Common::sample(const Node* node) { 89 _vdui = VerifyDUIterators; 90 _node = node; 91 _outcnt = node->_outcnt; 92 _del_tick = node->_del_tick; 93 _last = NULL; 94 } 95 96 void DUIterator_Common::verify(const Node* node, bool at_end_ok) { 97 assert(_node == node, "consistent iterator source"); 98 assert(_del_tick == node->_del_tick, "no unexpected deletions allowed"); 99 } 100 101 void DUIterator_Common::verify_resync() { 102 // Ensure that the loop body has just deleted the last guy produced. 103 const Node* node = _node; 104 // Ensure that at least one copy of the last-seen edge was deleted. 105 // Note: It is OK to delete multiple copies of the last-seen edge. 106 // Unfortunately, we have no way to verify that all the deletions delete 107 // that same edge. On this point we must use the Honor System. 108 assert(node->_del_tick >= _del_tick+1, "must have deleted an edge"); 109 assert(node->_last_del == _last, "must have deleted the edge just produced"); 110 // We liked this deletion, so accept the resulting outcnt and tick. 111 _outcnt = node->_outcnt; 112 _del_tick = node->_del_tick; 113 } 114 115 void DUIterator_Common::reset(const DUIterator_Common& that) { 116 if (this == &that) return; // ignore assignment to self 117 if (!_vdui) { 118 // We need to initialize everything, overwriting garbage values. 119 _last = that._last; 120 _vdui = that._vdui; 121 } 122 // Note: It is legal (though odd) for an iterator over some node x 123 // to be reassigned to iterate over another node y. Some doubly-nested 124 // progress loops depend on being able to do this. 125 const Node* node = that._node; 126 // Re-initialize everything, except _last. 127 _node = node; 128 _outcnt = node->_outcnt; 129 _del_tick = node->_del_tick; 130 } 131 132 void DUIterator::sample(const Node* node) { 133 DUIterator_Common::sample(node); // Initialize the assertion data. 134 _refresh_tick = 0; // No refreshes have happened, as yet. 135 } 136 137 void DUIterator::verify(const Node* node, bool at_end_ok) { 138 DUIterator_Common::verify(node, at_end_ok); 139 assert(_idx < node->_outcnt + (uint)at_end_ok, "idx in range"); 140 } 141 142 void DUIterator::verify_increment() { 143 if (_refresh_tick & 1) { 144 // We have refreshed the index during this loop. 145 // Fix up _idx to meet asserts. 146 if (_idx > _outcnt) _idx = _outcnt; 147 } 148 verify(_node, true); 149 } 150 151 void DUIterator::verify_resync() { 152 // Note: We do not assert on _outcnt, because insertions are OK here. 153 DUIterator_Common::verify_resync(); 154 // Make sure we are still in sync, possibly with no more out-edges: 155 verify(_node, true); 156 } 157 158 void DUIterator::reset(const DUIterator& that) { 159 if (this == &that) return; // self assignment is always a no-op 160 assert(that._refresh_tick == 0, "assign only the result of Node::outs()"); 161 assert(that._idx == 0, "assign only the result of Node::outs()"); 162 assert(_idx == that._idx, "already assigned _idx"); 163 if (!_vdui) { 164 // We need to initialize everything, overwriting garbage values. 165 sample(that._node); 166 } else { 167 DUIterator_Common::reset(that); 168 if (_refresh_tick & 1) { 169 _refresh_tick++; // Clear the "was refreshed" flag. 170 } 171 assert(_refresh_tick < 2*100000, "DU iteration must converge quickly"); 172 } 173 } 174 175 void DUIterator::refresh() { 176 DUIterator_Common::sample(_node); // Re-fetch assertion data. 177 _refresh_tick |= 1; // Set the "was refreshed" flag. 178 } 179 180 void DUIterator::verify_finish() { 181 // If the loop has killed the node, do not require it to re-run. 182 if (_node->_outcnt == 0) _refresh_tick &= ~1; 183 // If this assert triggers, it means that a loop used refresh_out_pos 184 // to re-synch an iteration index, but the loop did not correctly 185 // re-run itself, using a "while (progress)" construct. 186 // This iterator enforces the rule that you must keep trying the loop 187 // until it "runs clean" without any need for refreshing. 188 assert(!(_refresh_tick & 1), "the loop must run once with no refreshing"); 189 } 190 191 192 void DUIterator_Fast::verify(const Node* node, bool at_end_ok) { 193 DUIterator_Common::verify(node, at_end_ok); 194 Node** out = node->_out; 195 uint cnt = node->_outcnt; 196 assert(cnt == _outcnt, "no insertions allowed"); 197 assert(_outp >= out && _outp <= out + cnt - !at_end_ok, "outp in range"); 198 // This last check is carefully designed to work for NO_OUT_ARRAY. 199 } 200 201 void DUIterator_Fast::verify_limit() { 202 const Node* node = _node; 203 verify(node, true); 204 assert(_outp == node->_out + node->_outcnt, "limit still correct"); 205 } 206 207 void DUIterator_Fast::verify_resync() { 208 const Node* node = _node; 209 if (_outp == node->_out + _outcnt) { 210 // Note that the limit imax, not the pointer i, gets updated with the 211 // exact count of deletions. (For the pointer it's always "--i".) 212 assert(node->_outcnt+node->_del_tick == _outcnt+_del_tick, "no insertions allowed with deletion(s)"); 213 // This is a limit pointer, with a name like "imax". 214 // Fudge the _last field so that the common assert will be happy. 215 _last = (Node*) node->_last_del; 216 DUIterator_Common::verify_resync(); 217 } else { 218 assert(node->_outcnt < _outcnt, "no insertions allowed with deletion(s)"); 219 // A normal internal pointer. 220 DUIterator_Common::verify_resync(); 221 // Make sure we are still in sync, possibly with no more out-edges: 222 verify(node, true); 223 } 224 } 225 226 void DUIterator_Fast::verify_relimit(uint n) { 227 const Node* node = _node; 228 assert((int)n > 0, "use imax -= n only with a positive count"); 229 // This must be a limit pointer, with a name like "imax". 230 assert(_outp == node->_out + node->_outcnt, "apply -= only to a limit (imax)"); 231 // The reported number of deletions must match what the node saw. 232 assert(node->_del_tick == _del_tick + n, "must have deleted n edges"); 233 // Fudge the _last field so that the common assert will be happy. 234 _last = (Node*) node->_last_del; 235 DUIterator_Common::verify_resync(); 236 } 237 238 void DUIterator_Fast::reset(const DUIterator_Fast& that) { 239 assert(_outp == that._outp, "already assigned _outp"); 240 DUIterator_Common::reset(that); 241 } 242 243 void DUIterator_Last::verify(const Node* node, bool at_end_ok) { 244 // at_end_ok means the _outp is allowed to underflow by 1 245 _outp += at_end_ok; 246 DUIterator_Fast::verify(node, at_end_ok); // check _del_tick, etc. 247 _outp -= at_end_ok; 248 assert(_outp == (node->_out + node->_outcnt) - 1, "pointer must point to end of nodes"); 249 } 250 251 void DUIterator_Last::verify_limit() { 252 // Do not require the limit address to be resynched. 253 //verify(node, true); 254 assert(_outp == _node->_out, "limit still correct"); 255 } 256 257 void DUIterator_Last::verify_step(uint num_edges) { 258 assert((int)num_edges > 0, "need non-zero edge count for loop progress"); 259 _outcnt -= num_edges; 260 _del_tick += num_edges; 261 // Make sure we are still in sync, possibly with no more out-edges: 262 const Node* node = _node; 263 verify(node, true); 264 assert(node->_last_del == _last, "must have deleted the edge just produced"); 265 } 266 267 #endif //OPTO_DU_ITERATOR_ASSERT 268 269 270 #endif //ASSERT 271 272 273 // This constant used to initialize _out may be any non-null value. 274 // The value NULL is reserved for the top node only. 275 #define NO_OUT_ARRAY ((Node**)-1) 276 277 // This funny expression handshakes with Node::operator new 278 // to pull Compile::current out of the new node's _out field, 279 // and then calls a subroutine which manages most field 280 // initializations. The only one which is tricky is the 281 // _idx field, which is const, and so must be initialized 282 // by a return value, not an assignment. 283 // 284 // (Aren't you thankful that Java finals don't require so many tricks?) 285 #define IDX_INIT(req) this->Init((req), (Compile*) this->_out) 286 #ifdef _MSC_VER // the IDX_INIT hack falls foul of warning C4355 287 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list 288 #endif 289 290 // Out-of-line code from node constructors. 291 // Executed only when extra debug info. is being passed around. 292 static void init_node_notes(Compile* C, int idx, Node_Notes* nn) { 293 C->set_node_notes_at(idx, nn); 294 } 295 296 // Shared initialization code. 297 inline int Node::Init(int req, Compile* C) { 298 assert(Compile::current() == C, "must use operator new(Compile*)"); 299 int idx = C->next_unique(); 300 301 // Allocate memory for the necessary number of edges. 302 if (req > 0) { 303 // Allocate space for _in array to have double alignment. 304 _in = (Node **) ((char *) (C->node_arena()->Amalloc_D(req * sizeof(void*)))); 305 #ifdef ASSERT 306 _in[req-1] = this; // magic cookie for assertion check 307 #endif 308 } 309 // If there are default notes floating around, capture them: 310 Node_Notes* nn = C->default_node_notes(); 311 if (nn != NULL) init_node_notes(C, idx, nn); 312 313 // Note: At this point, C is dead, 314 // and we begin to initialize the new Node. 315 316 _cnt = _max = req; 317 _outcnt = _outmax = 0; 318 _class_id = Class_Node; 319 _flags = 0; 320 _out = NO_OUT_ARRAY; 321 return idx; 322 } 323 324 //------------------------------Node------------------------------------------- 325 // Create a Node, with a given number of required edges. 326 Node::Node(uint req) 327 : _idx(IDX_INIT(req)) 328 { 329 assert( req < (uint)(MaxNodeLimit - NodeLimitFudgeFactor), "Input limit exceeded" ); 330 debug_only( verify_construction() ); 331 NOT_PRODUCT(nodes_created++); 332 if (req == 0) { 333 assert( _in == (Node**)this, "Must not pass arg count to 'new'" ); 334 _in = NULL; 335 } else { 336 assert( _in[req-1] == this, "Must pass arg count to 'new'" ); 337 Node** to = _in; 338 for(uint i = 0; i < req; i++) { 339 to[i] = NULL; 340 } 341 } 342 } 343 344 //------------------------------Node------------------------------------------- 345 Node::Node(Node *n0) 346 : _idx(IDX_INIT(1)) 347 { 348 debug_only( verify_construction() ); 349 NOT_PRODUCT(nodes_created++); 350 // Assert we allocated space for input array already 351 assert( _in[0] == this, "Must pass arg count to 'new'" ); 352 assert( is_not_dead(n0), "can not use dead node"); 353 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); 354 } 355 356 //------------------------------Node------------------------------------------- 357 Node::Node(Node *n0, Node *n1) 358 : _idx(IDX_INIT(2)) 359 { 360 debug_only( verify_construction() ); 361 NOT_PRODUCT(nodes_created++); 362 // Assert we allocated space for input array already 363 assert( _in[1] == this, "Must pass arg count to 'new'" ); 364 assert( is_not_dead(n0), "can not use dead node"); 365 assert( is_not_dead(n1), "can not use dead node"); 366 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); 367 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); 368 } 369 370 //------------------------------Node------------------------------------------- 371 Node::Node(Node *n0, Node *n1, Node *n2) 372 : _idx(IDX_INIT(3)) 373 { 374 debug_only( verify_construction() ); 375 NOT_PRODUCT(nodes_created++); 376 // Assert we allocated space for input array already 377 assert( _in[2] == this, "Must pass arg count to 'new'" ); 378 assert( is_not_dead(n0), "can not use dead node"); 379 assert( is_not_dead(n1), "can not use dead node"); 380 assert( is_not_dead(n2), "can not use dead node"); 381 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); 382 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); 383 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this); 384 } 385 386 //------------------------------Node------------------------------------------- 387 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3) 388 : _idx(IDX_INIT(4)) 389 { 390 debug_only( verify_construction() ); 391 NOT_PRODUCT(nodes_created++); 392 // Assert we allocated space for input array already 393 assert( _in[3] == this, "Must pass arg count to 'new'" ); 394 assert( is_not_dead(n0), "can not use dead node"); 395 assert( is_not_dead(n1), "can not use dead node"); 396 assert( is_not_dead(n2), "can not use dead node"); 397 assert( is_not_dead(n3), "can not use dead node"); 398 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); 399 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); 400 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this); 401 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this); 402 } 403 404 //------------------------------Node------------------------------------------- 405 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3, Node *n4) 406 : _idx(IDX_INIT(5)) 407 { 408 debug_only( verify_construction() ); 409 NOT_PRODUCT(nodes_created++); 410 // Assert we allocated space for input array already 411 assert( _in[4] == this, "Must pass arg count to 'new'" ); 412 assert( is_not_dead(n0), "can not use dead node"); 413 assert( is_not_dead(n1), "can not use dead node"); 414 assert( is_not_dead(n2), "can not use dead node"); 415 assert( is_not_dead(n3), "can not use dead node"); 416 assert( is_not_dead(n4), "can not use dead node"); 417 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); 418 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); 419 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this); 420 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this); 421 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this); 422 } 423 424 //------------------------------Node------------------------------------------- 425 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3, 426 Node *n4, Node *n5) 427 : _idx(IDX_INIT(6)) 428 { 429 debug_only( verify_construction() ); 430 NOT_PRODUCT(nodes_created++); 431 // Assert we allocated space for input array already 432 assert( _in[5] == this, "Must pass arg count to 'new'" ); 433 assert( is_not_dead(n0), "can not use dead node"); 434 assert( is_not_dead(n1), "can not use dead node"); 435 assert( is_not_dead(n2), "can not use dead node"); 436 assert( is_not_dead(n3), "can not use dead node"); 437 assert( is_not_dead(n4), "can not use dead node"); 438 assert( is_not_dead(n5), "can not use dead node"); 439 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); 440 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); 441 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this); 442 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this); 443 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this); 444 _in[5] = n5; if (n5 != NULL) n5->add_out((Node *)this); 445 } 446 447 //------------------------------Node------------------------------------------- 448 Node::Node(Node *n0, Node *n1, Node *n2, Node *n3, 449 Node *n4, Node *n5, Node *n6) 450 : _idx(IDX_INIT(7)) 451 { 452 debug_only( verify_construction() ); 453 NOT_PRODUCT(nodes_created++); 454 // Assert we allocated space for input array already 455 assert( _in[6] == this, "Must pass arg count to 'new'" ); 456 assert( is_not_dead(n0), "can not use dead node"); 457 assert( is_not_dead(n1), "can not use dead node"); 458 assert( is_not_dead(n2), "can not use dead node"); 459 assert( is_not_dead(n3), "can not use dead node"); 460 assert( is_not_dead(n4), "can not use dead node"); 461 assert( is_not_dead(n5), "can not use dead node"); 462 assert( is_not_dead(n6), "can not use dead node"); 463 _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); 464 _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); 465 _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this); 466 _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this); 467 _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this); 468 _in[5] = n5; if (n5 != NULL) n5->add_out((Node *)this); 469 _in[6] = n6; if (n6 != NULL) n6->add_out((Node *)this); 470 } 471 472 473 //------------------------------clone------------------------------------------ 474 // Clone a Node. 475 Node *Node::clone() const { 476 Compile* C = Compile::current(); 477 uint s = size_of(); // Size of inherited Node 478 Node *n = (Node*)C->node_arena()->Amalloc_D(size_of() + _max*sizeof(Node*)); 479 Copy::conjoint_words_to_lower((HeapWord*)this, (HeapWord*)n, s); 480 // Set the new input pointer array 481 n->_in = (Node**)(((char*)n)+s); 482 // Cannot share the old output pointer array, so kill it 483 n->_out = NO_OUT_ARRAY; 484 // And reset the counters to 0 485 n->_outcnt = 0; 486 n->_outmax = 0; 487 // Unlock this guy, since he is not in any hash table. 488 debug_only(n->_hash_lock = 0); 489 // Walk the old node's input list to duplicate its edges 490 uint i; 491 for( i = 0; i < len(); i++ ) { 492 Node *x = in(i); 493 n->_in[i] = x; 494 if (x != NULL) x->add_out(n); 495 } 496 if (is_macro()) 497 C->add_macro_node(n); 498 if (is_expensive()) 499 C->add_expensive_node(n); 500 501 n->set_idx(C->next_unique()); // Get new unique index as well 502 debug_only( n->verify_construction() ); 503 NOT_PRODUCT(nodes_created++); 504 // Do not patch over the debug_idx of a clone, because it makes it 505 // impossible to break on the clone's moment of creation. 506 //debug_only( n->set_debug_idx( debug_idx() ) ); 507 508 C->copy_node_notes_to(n, (Node*) this); 509 510 // MachNode clone 511 uint nopnds; 512 if (this->is_Mach() && (nopnds = this->as_Mach()->num_opnds()) > 0) { 513 MachNode *mach = n->as_Mach(); 514 MachNode *mthis = this->as_Mach(); 515 // Get address of _opnd_array. 516 // It should be the same offset since it is the clone of this node. 517 MachOper **from = mthis->_opnds; 518 MachOper **to = (MachOper **)((size_t)(&mach->_opnds) + 519 pointer_delta((const void*)from, 520 (const void*)(&mthis->_opnds), 1)); 521 mach->_opnds = to; 522 for ( uint i = 0; i < nopnds; ++i ) { 523 to[i] = from[i]->clone(C); 524 } 525 } 526 // cloning CallNode may need to clone JVMState 527 if (n->is_Call()) { 528 n->as_Call()->clone_jvms(C); 529 } 530 if (n->is_SafePoint()) { 531 n->as_SafePoint()->clone_replaced_nodes(); 532 } 533 return n; // Return the clone 534 } 535 536 //---------------------------setup_is_top-------------------------------------- 537 // Call this when changing the top node, to reassert the invariants 538 // required by Node::is_top. See Compile::set_cached_top_node. 539 void Node::setup_is_top() { 540 if (this == (Node*)Compile::current()->top()) { 541 // This node has just become top. Kill its out array. 542 _outcnt = _outmax = 0; 543 _out = NULL; // marker value for top 544 assert(is_top(), "must be top"); 545 } else { 546 if (_out == NULL) _out = NO_OUT_ARRAY; 547 assert(!is_top(), "must not be top"); 548 } 549 } 550 551 552 //------------------------------~Node------------------------------------------ 553 // Fancy destructor; eagerly attempt to reclaim Node numberings and storage 554 extern int reclaim_idx ; 555 extern int reclaim_in ; 556 extern int reclaim_node; 557 void Node::destruct() { 558 // Eagerly reclaim unique Node numberings 559 Compile* compile = Compile::current(); 560 if ((uint)_idx+1 == compile->unique()) { 561 compile->set_unique(compile->unique()-1); 562 #ifdef ASSERT 563 reclaim_idx++; 564 #endif 565 } 566 // Clear debug info: 567 Node_Notes* nn = compile->node_notes_at(_idx); 568 if (nn != NULL) nn->clear(); 569 // Walk the input array, freeing the corresponding output edges 570 _cnt = _max; // forget req/prec distinction 571 uint i; 572 for( i = 0; i < _max; i++ ) { 573 set_req(i, NULL); 574 //assert(def->out(def->outcnt()-1) == (Node *)this,"bad def-use hacking in reclaim"); 575 } 576 assert(outcnt() == 0, "deleting a node must not leave a dangling use"); 577 // See if the input array was allocated just prior to the object 578 int edge_size = _max*sizeof(void*); 579 int out_edge_size = _outmax*sizeof(void*); 580 char *edge_end = ((char*)_in) + edge_size; 581 char *out_array = (char*)(_out == NO_OUT_ARRAY? NULL: _out); 582 char *out_edge_end = out_array + out_edge_size; 583 int node_size = size_of(); 584 585 // Free the output edge array 586 if (out_edge_size > 0) { 587 #ifdef ASSERT 588 if( out_edge_end == compile->node_arena()->hwm() ) 589 reclaim_in += out_edge_size; // count reclaimed out edges with in edges 590 #endif 591 compile->node_arena()->Afree(out_array, out_edge_size); 592 } 593 594 // Free the input edge array and the node itself 595 if( edge_end == (char*)this ) { 596 #ifdef ASSERT 597 if( edge_end+node_size == compile->node_arena()->hwm() ) { 598 reclaim_in += edge_size; 599 reclaim_node+= node_size; 600 } 601 #else 602 // It was; free the input array and object all in one hit 603 compile->node_arena()->Afree(_in,edge_size+node_size); 604 #endif 605 } else { 606 607 // Free just the input array 608 #ifdef ASSERT 609 if( edge_end == compile->node_arena()->hwm() ) 610 reclaim_in += edge_size; 611 #endif 612 compile->node_arena()->Afree(_in,edge_size); 613 614 // Free just the object 615 #ifdef ASSERT 616 if( ((char*)this) + node_size == compile->node_arena()->hwm() ) 617 reclaim_node+= node_size; 618 #else 619 compile->node_arena()->Afree(this,node_size); 620 #endif 621 } 622 if (is_macro()) { 623 compile->remove_macro_node(this); 624 } 625 if (is_expensive()) { 626 compile->remove_expensive_node(this); 627 } 628 if (is_SafePoint()) { 629 as_SafePoint()->delete_replaced_nodes(); 630 } 631 #ifdef ASSERT 632 // We will not actually delete the storage, but we'll make the node unusable. 633 *(address*)this = badAddress; // smash the C++ vtbl, probably 634 _in = _out = (Node**) badAddress; 635 _max = _cnt = _outmax = _outcnt = 0; 636 #endif 637 } 638 639 //------------------------------grow------------------------------------------- 640 // Grow the input array, making space for more edges 641 void Node::grow( uint len ) { 642 Arena* arena = Compile::current()->node_arena(); 643 uint new_max = _max; 644 if( new_max == 0 ) { 645 _max = 4; 646 _in = (Node**)arena->Amalloc(4*sizeof(Node*)); 647 Node** to = _in; 648 to[0] = NULL; 649 to[1] = NULL; 650 to[2] = NULL; 651 to[3] = NULL; 652 return; 653 } 654 while( new_max <= len ) new_max <<= 1; // Find next power-of-2 655 // Trimming to limit allows a uint8 to handle up to 255 edges. 656 // Previously I was using only powers-of-2 which peaked at 128 edges. 657 //if( new_max >= limit ) new_max = limit-1; 658 _in = (Node**)arena->Arealloc(_in, _max*sizeof(Node*), new_max*sizeof(Node*)); 659 Copy::zero_to_bytes(&_in[_max], (new_max-_max)*sizeof(Node*)); // NULL all new space 660 _max = new_max; // Record new max length 661 // This assertion makes sure that Node::_max is wide enough to 662 // represent the numerical value of new_max. 663 assert(_max == new_max && _max > len, "int width of _max is too small"); 664 } 665 666 //-----------------------------out_grow---------------------------------------- 667 // Grow the input array, making space for more edges 668 void Node::out_grow( uint len ) { 669 assert(!is_top(), "cannot grow a top node's out array"); 670 Arena* arena = Compile::current()->node_arena(); 671 uint new_max = _outmax; 672 if( new_max == 0 ) { 673 _outmax = 4; 674 _out = (Node **)arena->Amalloc(4*sizeof(Node*)); 675 return; 676 } 677 while( new_max <= len ) new_max <<= 1; // Find next power-of-2 678 // Trimming to limit allows a uint8 to handle up to 255 edges. 679 // Previously I was using only powers-of-2 which peaked at 128 edges. 680 //if( new_max >= limit ) new_max = limit-1; 681 assert(_out != NULL && _out != NO_OUT_ARRAY, "out must have sensible value"); 682 _out = (Node**)arena->Arealloc(_out,_outmax*sizeof(Node*),new_max*sizeof(Node*)); 683 //Copy::zero_to_bytes(&_out[_outmax], (new_max-_outmax)*sizeof(Node*)); // NULL all new space 684 _outmax = new_max; // Record new max length 685 // This assertion makes sure that Node::_max is wide enough to 686 // represent the numerical value of new_max. 687 assert(_outmax == new_max && _outmax > len, "int width of _outmax is too small"); 688 } 689 690 #ifdef ASSERT 691 //------------------------------is_dead---------------------------------------- 692 bool Node::is_dead() const { 693 // Mach and pinch point nodes may look like dead. 694 if( is_top() || is_Mach() || (Opcode() == Op_Node && _outcnt > 0) ) 695 return false; 696 for( uint i = 0; i < _max; i++ ) 697 if( _in[i] != NULL ) 698 return false; 699 dump(); 700 return true; 701 } 702 #endif 703 704 705 //------------------------------is_unreachable--------------------------------- 706 bool Node::is_unreachable(PhaseIterGVN &igvn) const { 707 assert(!is_Mach(), "doesn't work with MachNodes"); 708 return outcnt() == 0 || igvn.type(this) == Type::TOP || in(0)->is_top(); 709 } 710 711 //------------------------------add_req---------------------------------------- 712 // Add a new required input at the end 713 void Node::add_req( Node *n ) { 714 assert( is_not_dead(n), "can not use dead node"); 715 716 // Look to see if I can move precedence down one without reallocating 717 if( (_cnt >= _max) || (in(_max-1) != NULL) ) 718 grow( _max+1 ); 719 720 // Find a precedence edge to move 721 if( in(_cnt) != NULL ) { // Next precedence edge is busy? 722 uint i; 723 for( i=_cnt; i<_max; i++ ) 724 if( in(i) == NULL ) // Find the NULL at end of prec edge list 725 break; // There must be one, since we grew the array 726 _in[i] = in(_cnt); // Move prec over, making space for req edge 727 } 728 _in[_cnt++] = n; // Stuff over old prec edge 729 if (n != NULL) n->add_out((Node *)this); 730 } 731 732 //---------------------------add_req_batch------------------------------------- 733 // Add a new required input at the end 734 void Node::add_req_batch( Node *n, uint m ) { 735 assert( is_not_dead(n), "can not use dead node"); 736 // check various edge cases 737 if ((int)m <= 1) { 738 assert((int)m >= 0, "oob"); 739 if (m != 0) add_req(n); 740 return; 741 } 742 743 // Look to see if I can move precedence down one without reallocating 744 if( (_cnt+m) > _max || _in[_max-m] ) 745 grow( _max+m ); 746 747 // Find a precedence edge to move 748 if( _in[_cnt] != NULL ) { // Next precedence edge is busy? 749 uint i; 750 for( i=_cnt; i<_max; i++ ) 751 if( _in[i] == NULL ) // Find the NULL at end of prec edge list 752 break; // There must be one, since we grew the array 753 // Slide all the precs over by m positions (assume #prec << m). 754 Copy::conjoint_words_to_higher((HeapWord*)&_in[_cnt], (HeapWord*)&_in[_cnt+m], ((i-_cnt)*sizeof(Node*))); 755 } 756 757 // Stuff over the old prec edges 758 for(uint i=0; i<m; i++ ) { 759 _in[_cnt++] = n; 760 } 761 762 // Insert multiple out edges on the node. 763 if (n != NULL && !n->is_top()) { 764 for(uint i=0; i<m; i++ ) { 765 n->add_out((Node *)this); 766 } 767 } 768 } 769 770 //------------------------------del_req---------------------------------------- 771 // Delete the required edge and compact the edge array 772 void Node::del_req( uint idx ) { 773 assert( idx < _cnt, "oob"); 774 assert( !VerifyHashTableKeys || _hash_lock == 0, 775 "remove node from hash table before modifying it"); 776 // First remove corresponding def-use edge 777 Node *n = in(idx); 778 if (n != NULL) n->del_out((Node *)this); 779 _in[idx] = in(--_cnt); // Compact the array 780 _in[_cnt] = NULL; // NULL out emptied slot 781 } 782 783 //------------------------------del_req_ordered-------------------------------- 784 // Delete the required edge and compact the edge array with preserved order 785 void Node::del_req_ordered( uint idx ) { 786 assert( idx < _cnt, "oob"); 787 assert( !VerifyHashTableKeys || _hash_lock == 0, 788 "remove node from hash table before modifying it"); 789 // First remove corresponding def-use edge 790 Node *n = in(idx); 791 if (n != NULL) n->del_out((Node *)this); 792 if (idx < _cnt - 1) { // Not last edge ? 793 Copy::conjoint_words_to_lower((HeapWord*)&_in[idx+1], (HeapWord*)&_in[idx], ((_cnt-idx-1)*sizeof(Node*))); 794 } 795 _in[--_cnt] = NULL; // NULL out emptied slot 796 } 797 798 //------------------------------ins_req---------------------------------------- 799 // Insert a new required input at the end 800 void Node::ins_req( uint idx, Node *n ) { 801 assert( is_not_dead(n), "can not use dead node"); 802 add_req(NULL); // Make space 803 assert( idx < _max, "Must have allocated enough space"); 804 // Slide over 805 if(_cnt-idx-1 > 0) { 806 Copy::conjoint_words_to_higher((HeapWord*)&_in[idx], (HeapWord*)&_in[idx+1], ((_cnt-idx-1)*sizeof(Node*))); 807 } 808 _in[idx] = n; // Stuff over old required edge 809 if (n != NULL) n->add_out((Node *)this); // Add reciprocal def-use edge 810 } 811 812 //-----------------------------find_edge--------------------------------------- 813 int Node::find_edge(Node* n) { 814 for (uint i = 0; i < len(); i++) { 815 if (_in[i] == n) return i; 816 } 817 return -1; 818 } 819 820 //----------------------------replace_edge------------------------------------- 821 int Node::replace_edge(Node* old, Node* neww) { 822 if (old == neww) return 0; // nothing to do 823 uint nrep = 0; 824 for (uint i = 0; i < len(); i++) { 825 if (in(i) == old) { 826 if (i < req()) 827 set_req(i, neww); 828 else 829 set_prec(i, neww); 830 nrep++; 831 } 832 } 833 return nrep; 834 } 835 836 /** 837 * Replace input edges in the range pointing to 'old' node. 838 */ 839 int Node::replace_edges_in_range(Node* old, Node* neww, int start, int end) { 840 if (old == neww) return 0; // nothing to do 841 uint nrep = 0; 842 for (int i = start; i < end; i++) { 843 if (in(i) == old) { 844 set_req(i, neww); 845 nrep++; 846 } 847 } 848 return nrep; 849 } 850 851 //-------------------------disconnect_inputs----------------------------------- 852 // NULL out all inputs to eliminate incoming Def-Use edges. 853 // Return the number of edges between 'n' and 'this' 854 int Node::disconnect_inputs(Node *n, Compile* C) { 855 int edges_to_n = 0; 856 857 uint cnt = req(); 858 for( uint i = 0; i < cnt; ++i ) { 859 if( in(i) == 0 ) continue; 860 if( in(i) == n ) ++edges_to_n; 861 set_req(i, NULL); 862 } 863 // Remove precedence edges if any exist 864 // Note: Safepoints may have precedence edges, even during parsing 865 if( (req() != len()) && (in(req()) != NULL) ) { 866 uint max = len(); 867 for( uint i = 0; i < max; ++i ) { 868 if( in(i) == 0 ) continue; 869 if( in(i) == n ) ++edges_to_n; 870 set_prec(i, NULL); 871 } 872 } 873 874 // Node::destruct requires all out edges be deleted first 875 // debug_only(destruct();) // no reuse benefit expected 876 if (edges_to_n == 0) { 877 C->record_dead_node(_idx); 878 } 879 return edges_to_n; 880 } 881 882 //-----------------------------uncast--------------------------------------- 883 // %%% Temporary, until we sort out CheckCastPP vs. CastPP. 884 // Strip away casting. (It is depth-limited.) 885 Node* Node::uncast() const { 886 // Should be inline: 887 //return is_ConstraintCast() ? uncast_helper(this) : (Node*) this; 888 if (is_ConstraintCast() || is_CheckCastPP()) 889 return uncast_helper(this); 890 else 891 return (Node*) this; 892 } 893 894 //---------------------------uncast_helper------------------------------------- 895 Node* Node::uncast_helper(const Node* p) { 896 #ifdef ASSERT 897 uint depth_count = 0; 898 const Node* orig_p = p; 899 #endif 900 901 while (true) { 902 #ifdef ASSERT 903 if (depth_count >= K) { 904 orig_p->dump(4); 905 if (p != orig_p) 906 p->dump(1); 907 } 908 assert(depth_count++ < K, "infinite loop in Node::uncast_helper"); 909 #endif 910 if (p == NULL || p->req() != 2) { 911 break; 912 } else if (p->is_ConstraintCast()) { 913 p = p->in(1); 914 } else if (p->is_CheckCastPP()) { 915 p = p->in(1); 916 } else { 917 break; 918 } 919 } 920 return (Node*) p; 921 } 922 923 //------------------------------add_prec--------------------------------------- 924 // Add a new precedence input. Precedence inputs are unordered, with 925 // duplicates removed and NULLs packed down at the end. 926 void Node::add_prec( Node *n ) { 927 assert( is_not_dead(n), "can not use dead node"); 928 929 // Check for NULL at end 930 if( _cnt >= _max || in(_max-1) ) 931 grow( _max+1 ); 932 933 // Find a precedence edge to move 934 uint i = _cnt; 935 while( in(i) != NULL ) i++; 936 _in[i] = n; // Stuff prec edge over NULL 937 if ( n != NULL) n->add_out((Node *)this); // Add mirror edge 938 } 939 940 //------------------------------rm_prec---------------------------------------- 941 // Remove a precedence input. Precedence inputs are unordered, with 942 // duplicates removed and NULLs packed down at the end. 943 void Node::rm_prec( uint j ) { 944 945 // Find end of precedence list to pack NULLs 946 uint i; 947 for( i=j; i<_max; i++ ) 948 if( !_in[i] ) // Find the NULL at end of prec edge list 949 break; 950 if (_in[j] != NULL) _in[j]->del_out((Node *)this); 951 _in[j] = _in[--i]; // Move last element over removed guy 952 _in[i] = NULL; // NULL out last element 953 } 954 955 //------------------------------size_of---------------------------------------- 956 uint Node::size_of() const { return sizeof(*this); } 957 958 //------------------------------ideal_reg-------------------------------------- 959 uint Node::ideal_reg() const { return 0; } 960 961 //------------------------------jvms------------------------------------------- 962 JVMState* Node::jvms() const { return NULL; } 963 964 #ifdef ASSERT 965 //------------------------------jvms------------------------------------------- 966 bool Node::verify_jvms(const JVMState* using_jvms) const { 967 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) { 968 if (jvms == using_jvms) return true; 969 } 970 return false; 971 } 972 973 //------------------------------init_NodeProperty------------------------------ 974 void Node::init_NodeProperty() { 975 assert(_max_classes <= max_jushort, "too many NodeProperty classes"); 976 assert(_max_flags <= max_jushort, "too many NodeProperty flags"); 977 } 978 #endif 979 980 //------------------------------format----------------------------------------- 981 // Print as assembly 982 void Node::format( PhaseRegAlloc *, outputStream *st ) const {} 983 //------------------------------emit------------------------------------------- 984 // Emit bytes starting at parameter 'ptr'. 985 void Node::emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const {} 986 //------------------------------size------------------------------------------- 987 // Size of instruction in bytes 988 uint Node::size(PhaseRegAlloc *ra_) const { return 0; } 989 990 //------------------------------CFG Construction------------------------------- 991 // Nodes that end basic blocks, e.g. IfTrue/IfFalse, JumpProjNode, Root, 992 // Goto and Return. 993 const Node *Node::is_block_proj() const { return 0; } 994 995 // Minimum guaranteed type 996 const Type *Node::bottom_type() const { return Type::BOTTOM; } 997 998 999 //------------------------------raise_bottom_type------------------------------ 1000 // Get the worst-case Type output for this Node. 1001 void Node::raise_bottom_type(const Type* new_type) { 1002 if (is_Type()) { 1003 TypeNode *n = this->as_Type(); 1004 if (VerifyAliases) { 1005 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type"); 1006 } 1007 n->set_type(new_type); 1008 } else if (is_Load()) { 1009 LoadNode *n = this->as_Load(); 1010 if (VerifyAliases) { 1011 assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type"); 1012 } 1013 n->set_type(new_type); 1014 } 1015 } 1016 1017 //------------------------------Identity--------------------------------------- 1018 // Return a node that the given node is equivalent to. 1019 Node *Node::Identity( PhaseTransform * ) { 1020 return this; // Default to no identities 1021 } 1022 1023 //------------------------------Value------------------------------------------ 1024 // Compute a new Type for a node using the Type of the inputs. 1025 const Type *Node::Value( PhaseTransform * ) const { 1026 return bottom_type(); // Default to worst-case Type 1027 } 1028 1029 //------------------------------Ideal------------------------------------------ 1030 // 1031 // 'Idealize' the graph rooted at this Node. 1032 // 1033 // In order to be efficient and flexible there are some subtle invariants 1034 // these Ideal calls need to hold. Running with '+VerifyIterativeGVN' checks 1035 // these invariants, although its too slow to have on by default. If you are 1036 // hacking an Ideal call, be sure to test with +VerifyIterativeGVN! 1037 // 1038 // The Ideal call almost arbitrarily reshape the graph rooted at the 'this' 1039 // pointer. If ANY change is made, it must return the root of the reshaped 1040 // graph - even if the root is the same Node. Example: swapping the inputs 1041 // to an AddINode gives the same answer and same root, but you still have to 1042 // return the 'this' pointer instead of NULL. 1043 // 1044 // You cannot return an OLD Node, except for the 'this' pointer. Use the 1045 // Identity call to return an old Node; basically if Identity can find 1046 // another Node have the Ideal call make no change and return NULL. 1047 // Example: AddINode::Ideal must check for add of zero; in this case it 1048 // returns NULL instead of doing any graph reshaping. 1049 // 1050 // You cannot modify any old Nodes except for the 'this' pointer. Due to 1051 // sharing there may be other users of the old Nodes relying on their current 1052 // semantics. Modifying them will break the other users. 1053 // Example: when reshape "(X+3)+4" into "X+7" you must leave the Node for 1054 // "X+3" unchanged in case it is shared. 1055 // 1056 // If you modify the 'this' pointer's inputs, you should use 1057 // 'set_req'. If you are making a new Node (either as the new root or 1058 // some new internal piece) you may use 'init_req' to set the initial 1059 // value. You can make a new Node with either 'new' or 'clone'. In 1060 // either case, def-use info is correctly maintained. 1061 // 1062 // Example: reshape "(X+3)+4" into "X+7": 1063 // set_req(1, in(1)->in(1)); 1064 // set_req(2, phase->intcon(7)); 1065 // return this; 1066 // Example: reshape "X*4" into "X<<2" 1067 // return new (C) LShiftINode(in(1), phase->intcon(2)); 1068 // 1069 // You must call 'phase->transform(X)' on any new Nodes X you make, except 1070 // for the returned root node. Example: reshape "X*31" with "(X<<5)-X". 1071 // Node *shift=phase->transform(new(C)LShiftINode(in(1),phase->intcon(5))); 1072 // return new (C) AddINode(shift, in(1)); 1073 // 1074 // When making a Node for a constant use 'phase->makecon' or 'phase->intcon'. 1075 // These forms are faster than 'phase->transform(new (C) ConNode())' and Do 1076 // The Right Thing with def-use info. 1077 // 1078 // You cannot bury the 'this' Node inside of a graph reshape. If the reshaped 1079 // graph uses the 'this' Node it must be the root. If you want a Node with 1080 // the same Opcode as the 'this' pointer use 'clone'. 1081 // 1082 Node *Node::Ideal(PhaseGVN *phase, bool can_reshape) { 1083 return NULL; // Default to being Ideal already 1084 } 1085 1086 // Some nodes have specific Ideal subgraph transformations only if they are 1087 // unique users of specific nodes. Such nodes should be put on IGVN worklist 1088 // for the transformations to happen. 1089 bool Node::has_special_unique_user() const { 1090 assert(outcnt() == 1, "match only for unique out"); 1091 Node* n = unique_out(); 1092 int op = Opcode(); 1093 if( this->is_Store() ) { 1094 // Condition for back-to-back stores folding. 1095 return n->Opcode() == op && n->in(MemNode::Memory) == this; 1096 } else if (this->is_Load()) { 1097 // Condition for removing an unused LoadNode from the MemBarAcquire precedence input 1098 return n->Opcode() == Op_MemBarAcquire; 1099 } else if( op == Op_AddL ) { 1100 // Condition for convL2I(addL(x,y)) ==> addI(convL2I(x),convL2I(y)) 1101 return n->Opcode() == Op_ConvL2I && n->in(1) == this; 1102 } else if( op == Op_SubI || op == Op_SubL ) { 1103 // Condition for subI(x,subI(y,z)) ==> subI(addI(x,z),y) 1104 return n->Opcode() == op && n->in(2) == this; 1105 } 1106 return false; 1107 }; 1108 1109 //--------------------------find_exact_control--------------------------------- 1110 // Skip Proj and CatchProj nodes chains. Check for Null and Top. 1111 Node* Node::find_exact_control(Node* ctrl) { 1112 if (ctrl == NULL && this->is_Region()) 1113 ctrl = this->as_Region()->is_copy(); 1114 1115 if (ctrl != NULL && ctrl->is_CatchProj()) { 1116 if (ctrl->as_CatchProj()->_con == CatchProjNode::fall_through_index) 1117 ctrl = ctrl->in(0); 1118 if (ctrl != NULL && !ctrl->is_top()) 1119 ctrl = ctrl->in(0); 1120 } 1121 1122 if (ctrl != NULL && ctrl->is_Proj()) 1123 ctrl = ctrl->in(0); 1124 1125 return ctrl; 1126 } 1127 1128 //--------------------------dominates------------------------------------------ 1129 // Helper function for MemNode::all_controls_dominate(). 1130 // Check if 'this' control node dominates or equal to 'sub' control node. 1131 // We already know that if any path back to Root or Start reaches 'this', 1132 // then all paths so, so this is a simple search for one example, 1133 // not an exhaustive search for a counterexample. 1134 bool Node::dominates(Node* sub, Node_List &nlist) { 1135 assert(this->is_CFG(), "expecting control"); 1136 assert(sub != NULL && sub->is_CFG(), "expecting control"); 1137 1138 // detect dead cycle without regions 1139 int iterations_without_region_limit = DominatorSearchLimit; 1140 1141 Node* orig_sub = sub; 1142 Node* dom = this; 1143 bool met_dom = false; 1144 nlist.clear(); 1145 1146 // Walk 'sub' backward up the chain to 'dom', watching for regions. 1147 // After seeing 'dom', continue up to Root or Start. 1148 // If we hit a region (backward split point), it may be a loop head. 1149 // Keep going through one of the region's inputs. If we reach the 1150 // same region again, go through a different input. Eventually we 1151 // will either exit through the loop head, or give up. 1152 // (If we get confused, break out and return a conservative 'false'.) 1153 while (sub != NULL) { 1154 if (sub->is_top()) break; // Conservative answer for dead code. 1155 if (sub == dom) { 1156 if (nlist.size() == 0) { 1157 // No Region nodes except loops were visited before and the EntryControl 1158 // path was taken for loops: it did not walk in a cycle. 1159 return true; 1160 } else if (met_dom) { 1161 break; // already met before: walk in a cycle 1162 } else { 1163 // Region nodes were visited. Continue walk up to Start or Root 1164 // to make sure that it did not walk in a cycle. 1165 met_dom = true; // first time meet 1166 iterations_without_region_limit = DominatorSearchLimit; // Reset 1167 } 1168 } 1169 if (sub->is_Start() || sub->is_Root()) { 1170 // Success if we met 'dom' along a path to Start or Root. 1171 // We assume there are no alternative paths that avoid 'dom'. 1172 // (This assumption is up to the caller to ensure!) 1173 return met_dom; 1174 } 1175 Node* up = sub->in(0); 1176 // Normalize simple pass-through regions and projections: 1177 up = sub->find_exact_control(up); 1178 // If sub == up, we found a self-loop. Try to push past it. 1179 if (sub == up && sub->is_Loop()) { 1180 // Take loop entry path on the way up to 'dom'. 1181 up = sub->in(1); // in(LoopNode::EntryControl); 1182 } else if (sub == up && sub->is_Region() && sub->req() != 3) { 1183 // Always take in(1) path on the way up to 'dom' for clone regions 1184 // (with only one input) or regions which merge > 2 paths 1185 // (usually used to merge fast/slow paths). 1186 up = sub->in(1); 1187 } else if (sub == up && sub->is_Region()) { 1188 // Try both paths for Regions with 2 input paths (it may be a loop head). 1189 // It could give conservative 'false' answer without information 1190 // which region's input is the entry path. 1191 iterations_without_region_limit = DominatorSearchLimit; // Reset 1192 1193 bool region_was_visited_before = false; 1194 // Was this Region node visited before? 1195 // If so, we have reached it because we accidentally took a 1196 // loop-back edge from 'sub' back into the body of the loop, 1197 // and worked our way up again to the loop header 'sub'. 1198 // So, take the first unexplored path on the way up to 'dom'. 1199 for (int j = nlist.size() - 1; j >= 0; j--) { 1200 intptr_t ni = (intptr_t)nlist.at(j); 1201 Node* visited = (Node*)(ni & ~1); 1202 bool visited_twice_already = ((ni & 1) != 0); 1203 if (visited == sub) { 1204 if (visited_twice_already) { 1205 // Visited 2 paths, but still stuck in loop body. Give up. 1206 return false; 1207 } 1208 // The Region node was visited before only once. 1209 // (We will repush with the low bit set, below.) 1210 nlist.remove(j); 1211 // We will find a new edge and re-insert. 1212 region_was_visited_before = true; 1213 break; 1214 } 1215 } 1216 1217 // Find an incoming edge which has not been seen yet; walk through it. 1218 assert(up == sub, ""); 1219 uint skip = region_was_visited_before ? 1 : 0; 1220 for (uint i = 1; i < sub->req(); i++) { 1221 Node* in = sub->in(i); 1222 if (in != NULL && !in->is_top() && in != sub) { 1223 if (skip == 0) { 1224 up = in; 1225 break; 1226 } 1227 --skip; // skip this nontrivial input 1228 } 1229 } 1230 1231 // Set 0 bit to indicate that both paths were taken. 1232 nlist.push((Node*)((intptr_t)sub + (region_was_visited_before ? 1 : 0))); 1233 } 1234 1235 if (up == sub) { 1236 break; // some kind of tight cycle 1237 } 1238 if (up == orig_sub && met_dom) { 1239 // returned back after visiting 'dom' 1240 break; // some kind of cycle 1241 } 1242 if (--iterations_without_region_limit < 0) { 1243 break; // dead cycle 1244 } 1245 sub = up; 1246 } 1247 1248 // Did not meet Root or Start node in pred. chain. 1249 // Conservative answer for dead code. 1250 return false; 1251 } 1252 1253 //------------------------------remove_dead_region----------------------------- 1254 // This control node is dead. Follow the subgraph below it making everything 1255 // using it dead as well. This will happen normally via the usual IterGVN 1256 // worklist but this call is more efficient. Do not update use-def info 1257 // inside the dead region, just at the borders. 1258 static void kill_dead_code( Node *dead, PhaseIterGVN *igvn ) { 1259 // Con's are a popular node to re-hit in the hash table again. 1260 if( dead->is_Con() ) return; 1261 1262 // Can't put ResourceMark here since igvn->_worklist uses the same arena 1263 // for verify pass with +VerifyOpto and we add/remove elements in it here. 1264 Node_List nstack(Thread::current()->resource_area()); 1265 1266 Node *top = igvn->C->top(); 1267 nstack.push(dead); 1268 bool has_irreducible_loop = igvn->C->has_irreducible_loop(); 1269 1270 while (nstack.size() > 0) { 1271 dead = nstack.pop(); 1272 if (dead->outcnt() > 0) { 1273 // Keep dead node on stack until all uses are processed. 1274 nstack.push(dead); 1275 // For all Users of the Dead... ;-) 1276 for (DUIterator_Last kmin, k = dead->last_outs(kmin); k >= kmin; ) { 1277 Node* use = dead->last_out(k); 1278 igvn->hash_delete(use); // Yank from hash table prior to mod 1279 if (use->in(0) == dead) { // Found another dead node 1280 assert (!use->is_Con(), "Control for Con node should be Root node."); 1281 use->set_req(0, top); // Cut dead edge to prevent processing 1282 nstack.push(use); // the dead node again. 1283 } else if (!has_irreducible_loop && // Backedge could be alive in irreducible loop 1284 use->is_Loop() && !use->is_Root() && // Don't kill Root (RootNode extends LoopNode) 1285 use->in(LoopNode::EntryControl) == dead) { // Dead loop if its entry is dead 1286 use->set_req(LoopNode::EntryControl, top); // Cut dead edge to prevent processing 1287 use->set_req(0, top); // Cut self edge 1288 nstack.push(use); 1289 } else { // Else found a not-dead user 1290 // Dead if all inputs are top or null 1291 bool dead_use = !use->is_Root(); // Keep empty graph alive 1292 for (uint j = 1; j < use->req(); j++) { 1293 Node* in = use->in(j); 1294 if (in == dead) { // Turn all dead inputs into TOP 1295 use->set_req(j, top); 1296 } else if (in != NULL && !in->is_top()) { 1297 dead_use = false; 1298 } 1299 } 1300 if (dead_use) { 1301 if (use->is_Region()) { 1302 use->set_req(0, top); // Cut self edge 1303 } 1304 nstack.push(use); 1305 } else { 1306 igvn->_worklist.push(use); 1307 } 1308 } 1309 // Refresh the iterator, since any number of kills might have happened. 1310 k = dead->last_outs(kmin); 1311 } 1312 } else { // (dead->outcnt() == 0) 1313 // Done with outputs. 1314 igvn->hash_delete(dead); 1315 igvn->_worklist.remove(dead); 1316 igvn->set_type(dead, Type::TOP); 1317 if (dead->is_macro()) { 1318 igvn->C->remove_macro_node(dead); 1319 } 1320 if (dead->is_expensive()) { 1321 igvn->C->remove_expensive_node(dead); 1322 } 1323 igvn->C->record_dead_node(dead->_idx); 1324 // Kill all inputs to the dead guy 1325 for (uint i=0; i < dead->req(); i++) { 1326 Node *n = dead->in(i); // Get input to dead guy 1327 if (n != NULL && !n->is_top()) { // Input is valid? 1328 dead->set_req(i, top); // Smash input away 1329 if (n->outcnt() == 0) { // Input also goes dead? 1330 if (!n->is_Con()) 1331 nstack.push(n); // Clear it out as well 1332 } else if (n->outcnt() == 1 && 1333 n->has_special_unique_user()) { 1334 igvn->add_users_to_worklist( n ); 1335 } else if (n->outcnt() <= 2 && n->is_Store()) { 1336 // Push store's uses on worklist to enable folding optimization for 1337 // store/store and store/load to the same address. 1338 // The restriction (outcnt() <= 2) is the same as in set_req_X() 1339 // and remove_globally_dead_node(). 1340 igvn->add_users_to_worklist( n ); 1341 } 1342 } 1343 } 1344 } // (dead->outcnt() == 0) 1345 } // while (nstack.size() > 0) for outputs 1346 return; 1347 } 1348 1349 //------------------------------remove_dead_region----------------------------- 1350 bool Node::remove_dead_region(PhaseGVN *phase, bool can_reshape) { 1351 Node *n = in(0); 1352 if( !n ) return false; 1353 // Lost control into this guy? I.e., it became unreachable? 1354 // Aggressively kill all unreachable code. 1355 if (can_reshape && n->is_top()) { 1356 kill_dead_code(this, phase->is_IterGVN()); 1357 return false; // Node is dead. 1358 } 1359 1360 if( n->is_Region() && n->as_Region()->is_copy() ) { 1361 Node *m = n->nonnull_req(); 1362 set_req(0, m); 1363 return true; 1364 } 1365 return false; 1366 } 1367 1368 //------------------------------Ideal_DU_postCCP------------------------------- 1369 // Idealize graph, using DU info. Must clone result into new-space 1370 Node *Node::Ideal_DU_postCCP( PhaseCCP * ) { 1371 return NULL; // Default to no change 1372 } 1373 1374 //------------------------------hash------------------------------------------- 1375 // Hash function over Nodes. 1376 uint Node::hash() const { 1377 uint sum = 0; 1378 for( uint i=0; i<_cnt; i++ ) // Add in all inputs 1379 sum = (sum<<1)-(uintptr_t)in(i); // Ignore embedded NULLs 1380 return (sum>>2) + _cnt + Opcode(); 1381 } 1382 1383 //------------------------------cmp-------------------------------------------- 1384 // Compare special parts of simple Nodes 1385 uint Node::cmp( const Node &n ) const { 1386 return 1; // Must be same 1387 } 1388 1389 //------------------------------rematerialize----------------------------------- 1390 // Should we clone rather than spill this instruction? 1391 bool Node::rematerialize() const { 1392 if ( is_Mach() ) 1393 return this->as_Mach()->rematerialize(); 1394 else 1395 return (_flags & Flag_rematerialize) != 0; 1396 } 1397 1398 //------------------------------needs_anti_dependence_check--------------------- 1399 // Nodes which use memory without consuming it, hence need antidependences. 1400 bool Node::needs_anti_dependence_check() const { 1401 if( req() < 2 || (_flags & Flag_needs_anti_dependence_check) == 0 ) 1402 return false; 1403 else 1404 return in(1)->bottom_type()->has_memory(); 1405 } 1406 1407 1408 // Get an integer constant from a ConNode (or CastIINode). 1409 // Return a default value if there is no apparent constant here. 1410 const TypeInt* Node::find_int_type() const { 1411 if (this->is_Type()) { 1412 return this->as_Type()->type()->isa_int(); 1413 } else if (this->is_Con()) { 1414 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode"); 1415 return this->bottom_type()->isa_int(); 1416 } 1417 return NULL; 1418 } 1419 1420 // Get a pointer constant from a ConstNode. 1421 // Returns the constant if it is a pointer ConstNode 1422 intptr_t Node::get_ptr() const { 1423 assert( Opcode() == Op_ConP, "" ); 1424 return ((ConPNode*)this)->type()->is_ptr()->get_con(); 1425 } 1426 1427 // Get a narrow oop constant from a ConNNode. 1428 intptr_t Node::get_narrowcon() const { 1429 assert( Opcode() == Op_ConN, "" ); 1430 return ((ConNNode*)this)->type()->is_narrowoop()->get_con(); 1431 } 1432 1433 // Get a long constant from a ConNode. 1434 // Return a default value if there is no apparent constant here. 1435 const TypeLong* Node::find_long_type() const { 1436 if (this->is_Type()) { 1437 return this->as_Type()->type()->isa_long(); 1438 } else if (this->is_Con()) { 1439 assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode"); 1440 return this->bottom_type()->isa_long(); 1441 } 1442 return NULL; 1443 } 1444 1445 1446 /** 1447 * Return a ptr type for nodes which should have it. 1448 */ 1449 const TypePtr* Node::get_ptr_type() const { 1450 const TypePtr* tp = this->bottom_type()->make_ptr(); 1451 #ifdef ASSERT 1452 if (tp == NULL) { 1453 this->dump(1); 1454 assert((tp != NULL), "unexpected node type"); 1455 } 1456 #endif 1457 return tp; 1458 } 1459 1460 // Get a double constant from a ConstNode. 1461 // Returns the constant if it is a double ConstNode 1462 jdouble Node::getd() const { 1463 assert( Opcode() == Op_ConD, "" ); 1464 return ((ConDNode*)this)->type()->is_double_constant()->getd(); 1465 } 1466 1467 // Get a float constant from a ConstNode. 1468 // Returns the constant if it is a float ConstNode 1469 jfloat Node::getf() const { 1470 assert( Opcode() == Op_ConF, "" ); 1471 return ((ConFNode*)this)->type()->is_float_constant()->getf(); 1472 } 1473 1474 #ifndef PRODUCT 1475 1476 //----------------------------NotANode---------------------------------------- 1477 // Used in debugging code to avoid walking across dead or uninitialized edges. 1478 static inline bool NotANode(const Node* n) { 1479 if (n == NULL) return true; 1480 if (((intptr_t)n & 1) != 0) return true; // uninitialized, etc. 1481 if (*(address*)n == badAddress) return true; // kill by Node::destruct 1482 return false; 1483 } 1484 1485 1486 //------------------------------find------------------------------------------ 1487 // Find a neighbor of this Node with the given _idx 1488 // If idx is negative, find its absolute value, following both _in and _out. 1489 static void find_recur(Compile* C, Node* &result, Node *n, int idx, bool only_ctrl, 1490 VectorSet* old_space, VectorSet* new_space ) { 1491 int node_idx = (idx >= 0) ? idx : -idx; 1492 if (NotANode(n)) return; // Gracefully handle NULL, -1, 0xabababab, etc. 1493 // Contained in new_space or old_space? Check old_arena first since it's mostly empty. 1494 VectorSet *v = C->old_arena()->contains(n) ? old_space : new_space; 1495 if( v->test(n->_idx) ) return; 1496 if( (int)n->_idx == node_idx 1497 debug_only(|| n->debug_idx() == node_idx) ) { 1498 if (result != NULL) 1499 tty->print("find: " INTPTR_FORMAT " and " INTPTR_FORMAT " both have idx==%d\n", 1500 (uintptr_t)result, (uintptr_t)n, node_idx); 1501 result = n; 1502 } 1503 v->set(n->_idx); 1504 for( uint i=0; i<n->len(); i++ ) { 1505 if( only_ctrl && !(n->is_Region()) && (n->Opcode() != Op_Root) && (i != TypeFunc::Control) ) continue; 1506 find_recur(C, result, n->in(i), idx, only_ctrl, old_space, new_space ); 1507 } 1508 // Search along forward edges also: 1509 if (idx < 0 && !only_ctrl) { 1510 for( uint j=0; j<n->outcnt(); j++ ) { 1511 find_recur(C, result, n->raw_out(j), idx, only_ctrl, old_space, new_space ); 1512 } 1513 } 1514 #ifdef ASSERT 1515 // Search along debug_orig edges last, checking for cycles 1516 Node* orig = n->debug_orig(); 1517 if (orig != NULL) { 1518 do { 1519 if (NotANode(orig)) break; 1520 find_recur(C, result, orig, idx, only_ctrl, old_space, new_space ); 1521 orig = orig->debug_orig(); 1522 } while (orig != NULL && orig != n->debug_orig()); 1523 } 1524 #endif //ASSERT 1525 } 1526 1527 // call this from debugger: 1528 Node* find_node(Node* n, int idx) { 1529 return n->find(idx); 1530 } 1531 1532 //------------------------------find------------------------------------------- 1533 Node* Node::find(int idx) const { 1534 ResourceArea *area = Thread::current()->resource_area(); 1535 VectorSet old_space(area), new_space(area); 1536 Node* result = NULL; 1537 find_recur(Compile::current(), result, (Node*) this, idx, false, &old_space, &new_space ); 1538 return result; 1539 } 1540 1541 //------------------------------find_ctrl-------------------------------------- 1542 // Find an ancestor to this node in the control history with given _idx 1543 Node* Node::find_ctrl(int idx) const { 1544 ResourceArea *area = Thread::current()->resource_area(); 1545 VectorSet old_space(area), new_space(area); 1546 Node* result = NULL; 1547 find_recur(Compile::current(), result, (Node*) this, idx, true, &old_space, &new_space ); 1548 return result; 1549 } 1550 #endif 1551 1552 1553 1554 #ifndef PRODUCT 1555 1556 // -----------------------------Name------------------------------------------- 1557 extern const char *NodeClassNames[]; 1558 const char *Node::Name() const { return NodeClassNames[Opcode()]; } 1559 1560 static bool is_disconnected(const Node* n) { 1561 for (uint i = 0; i < n->req(); i++) { 1562 if (n->in(i) != NULL) return false; 1563 } 1564 return true; 1565 } 1566 1567 #ifdef ASSERT 1568 static void dump_orig(Node* orig, outputStream *st) { 1569 Compile* C = Compile::current(); 1570 if (NotANode(orig)) orig = NULL; 1571 if (orig != NULL && !C->node_arena()->contains(orig)) orig = NULL; 1572 if (orig == NULL) return; 1573 st->print(" !orig="); 1574 Node* fast = orig->debug_orig(); // tortoise & hare algorithm to detect loops 1575 if (NotANode(fast)) fast = NULL; 1576 while (orig != NULL) { 1577 bool discon = is_disconnected(orig); // if discon, print [123] else 123 1578 if (discon) st->print("["); 1579 if (!Compile::current()->node_arena()->contains(orig)) 1580 st->print("o"); 1581 st->print("%d", orig->_idx); 1582 if (discon) st->print("]"); 1583 orig = orig->debug_orig(); 1584 if (NotANode(orig)) orig = NULL; 1585 if (orig != NULL && !C->node_arena()->contains(orig)) orig = NULL; 1586 if (orig != NULL) st->print(","); 1587 if (fast != NULL) { 1588 // Step fast twice for each single step of orig: 1589 fast = fast->debug_orig(); 1590 if (NotANode(fast)) fast = NULL; 1591 if (fast != NULL && fast != orig) { 1592 fast = fast->debug_orig(); 1593 if (NotANode(fast)) fast = NULL; 1594 } 1595 if (fast == orig) { 1596 st->print("..."); 1597 break; 1598 } 1599 } 1600 } 1601 } 1602 1603 void Node::set_debug_orig(Node* orig) { 1604 _debug_orig = orig; 1605 if (BreakAtNode == 0) return; 1606 if (NotANode(orig)) orig = NULL; 1607 int trip = 10; 1608 while (orig != NULL) { 1609 if (orig->debug_idx() == BreakAtNode || (int)orig->_idx == BreakAtNode) { 1610 tty->print_cr("BreakAtNode: _idx=%d _debug_idx=%d orig._idx=%d orig._debug_idx=%d", 1611 this->_idx, this->debug_idx(), orig->_idx, orig->debug_idx()); 1612 BREAKPOINT; 1613 } 1614 orig = orig->debug_orig(); 1615 if (NotANode(orig)) orig = NULL; 1616 if (trip-- <= 0) break; 1617 } 1618 } 1619 #endif //ASSERT 1620 1621 //------------------------------dump------------------------------------------ 1622 // Dump a Node 1623 void Node::dump(const char* suffix, outputStream *st) const { 1624 Compile* C = Compile::current(); 1625 bool is_new = C->node_arena()->contains(this); 1626 C->_in_dump_cnt++; 1627 st->print("%c%d\t%s\t=== ", is_new ? ' ' : 'o', _idx, Name()); 1628 1629 // Dump the required and precedence inputs 1630 dump_req(st); 1631 dump_prec(st); 1632 // Dump the outputs 1633 dump_out(st); 1634 1635 if (is_disconnected(this)) { 1636 #ifdef ASSERT 1637 st->print(" [%d]",debug_idx()); 1638 dump_orig(debug_orig(), st); 1639 #endif 1640 st->cr(); 1641 C->_in_dump_cnt--; 1642 return; // don't process dead nodes 1643 } 1644 1645 // Dump node-specific info 1646 dump_spec(st); 1647 #ifdef ASSERT 1648 // Dump the non-reset _debug_idx 1649 if (Verbose && WizardMode) { 1650 st->print(" [%d]",debug_idx()); 1651 } 1652 #endif 1653 1654 const Type *t = bottom_type(); 1655 1656 if (t != NULL && (t->isa_instptr() || t->isa_klassptr())) { 1657 const TypeInstPtr *toop = t->isa_instptr(); 1658 const TypeKlassPtr *tkls = t->isa_klassptr(); 1659 ciKlass* klass = toop ? toop->klass() : (tkls ? tkls->klass() : NULL ); 1660 if (klass && klass->is_loaded() && klass->is_interface()) { 1661 st->print(" Interface:"); 1662 } else if (toop) { 1663 st->print(" Oop:"); 1664 } else if (tkls) { 1665 st->print(" Klass:"); 1666 } 1667 t->dump_on(st); 1668 } else if (t == Type::MEMORY) { 1669 st->print(" Memory:"); 1670 MemNode::dump_adr_type(this, adr_type(), st); 1671 } else if (Verbose || WizardMode) { 1672 st->print(" Type:"); 1673 if (t) { 1674 t->dump_on(st); 1675 } else { 1676 st->print("no type"); 1677 } 1678 } else if (t->isa_vect() && this->is_MachSpillCopy()) { 1679 // Dump MachSpillcopy vector type. 1680 t->dump_on(st); 1681 } 1682 if (is_new) { 1683 debug_only(dump_orig(debug_orig(), st)); 1684 Node_Notes* nn = C->node_notes_at(_idx); 1685 if (nn != NULL && !nn->is_clear()) { 1686 if (nn->jvms() != NULL) { 1687 st->print(" !jvms:"); 1688 nn->jvms()->dump_spec(st); 1689 } 1690 } 1691 } 1692 if (suffix) st->print("%s", suffix); 1693 C->_in_dump_cnt--; 1694 } 1695 1696 //------------------------------dump_req-------------------------------------- 1697 void Node::dump_req(outputStream *st) const { 1698 // Dump the required input edges 1699 for (uint i = 0; i < req(); i++) { // For all required inputs 1700 Node* d = in(i); 1701 if (d == NULL) { 1702 st->print("_ "); 1703 } else if (NotANode(d)) { 1704 st->print("NotANode "); // uninitialized, sentinel, garbage, etc. 1705 } else { 1706 st->print("%c%d ", Compile::current()->node_arena()->contains(d) ? ' ' : 'o', d->_idx); 1707 } 1708 } 1709 } 1710 1711 1712 //------------------------------dump_prec------------------------------------- 1713 void Node::dump_prec(outputStream *st) const { 1714 // Dump the precedence edges 1715 int any_prec = 0; 1716 for (uint i = req(); i < len(); i++) { // For all precedence inputs 1717 Node* p = in(i); 1718 if (p != NULL) { 1719 if (!any_prec++) st->print(" |"); 1720 if (NotANode(p)) { st->print("NotANode "); continue; } 1721 st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx); 1722 } 1723 } 1724 } 1725 1726 //------------------------------dump_out-------------------------------------- 1727 void Node::dump_out(outputStream *st) const { 1728 // Delimit the output edges 1729 st->print(" [["); 1730 // Dump the output edges 1731 for (uint i = 0; i < _outcnt; i++) { // For all outputs 1732 Node* u = _out[i]; 1733 if (u == NULL) { 1734 st->print("_ "); 1735 } else if (NotANode(u)) { 1736 st->print("NotANode "); 1737 } else { 1738 st->print("%c%d ", Compile::current()->node_arena()->contains(u) ? ' ' : 'o', u->_idx); 1739 } 1740 } 1741 st->print("]] "); 1742 } 1743 1744 //------------------------------dump_nodes------------------------------------- 1745 static void dump_nodes(const Node* start, int d, bool only_ctrl) { 1746 Node* s = (Node*)start; // remove const 1747 if (NotANode(s)) return; 1748 1749 uint depth = (uint)ABS(d); 1750 int direction = d; 1751 Compile* C = Compile::current(); 1752 GrowableArray <Node *> nstack(C->unique()); 1753 1754 nstack.append(s); 1755 int begin = 0; 1756 int end = 0; 1757 for(uint i = 0; i < depth; i++) { 1758 end = nstack.length(); 1759 for(int j = begin; j < end; j++) { 1760 Node* tp = nstack.at(j); 1761 uint limit = direction > 0 ? tp->len() : tp->outcnt(); 1762 for(uint k = 0; k < limit; k++) { 1763 Node* n = direction > 0 ? tp->in(k) : tp->raw_out(k); 1764 1765 if (NotANode(n)) continue; 1766 // do not recurse through top or the root (would reach unrelated stuff) 1767 if (n->is_Root() || n->is_top()) continue; 1768 if (only_ctrl && !n->is_CFG()) continue; 1769 1770 bool on_stack = nstack.contains(n); 1771 if (!on_stack) { 1772 nstack.append(n); 1773 } 1774 } 1775 } 1776 begin = end; 1777 } 1778 end = nstack.length(); 1779 if (direction > 0) { 1780 for(int j = end-1; j >= 0; j--) { 1781 nstack.at(j)->dump(); 1782 } 1783 } else { 1784 for(int j = 0; j < end; j++) { 1785 nstack.at(j)->dump(); 1786 } 1787 } 1788 } 1789 1790 //------------------------------dump------------------------------------------- 1791 void Node::dump(int d) const { 1792 dump_nodes(this, d, false); 1793 } 1794 1795 //------------------------------dump_ctrl-------------------------------------- 1796 // Dump a Node's control history to depth 1797 void Node::dump_ctrl(int d) const { 1798 dump_nodes(this, d, true); 1799 } 1800 1801 // VERIFICATION CODE 1802 // For each input edge to a node (ie - for each Use-Def edge), verify that 1803 // there is a corresponding Def-Use edge. 1804 //------------------------------verify_edges----------------------------------- 1805 void Node::verify_edges(Unique_Node_List &visited) { 1806 uint i, j, idx; 1807 int cnt; 1808 Node *n; 1809 1810 // Recursive termination test 1811 if (visited.member(this)) return; 1812 visited.push(this); 1813 1814 // Walk over all input edges, checking for correspondence 1815 for( i = 0; i < len(); i++ ) { 1816 n = in(i); 1817 if (n != NULL && !n->is_top()) { 1818 // Count instances of (Node *)this 1819 cnt = 0; 1820 for (idx = 0; idx < n->_outcnt; idx++ ) { 1821 if (n->_out[idx] == (Node *)this) cnt++; 1822 } 1823 assert( cnt > 0,"Failed to find Def-Use edge." ); 1824 // Check for duplicate edges 1825 // walk the input array downcounting the input edges to n 1826 for( j = 0; j < len(); j++ ) { 1827 if( in(j) == n ) cnt--; 1828 } 1829 assert( cnt == 0,"Mismatched edge count."); 1830 } else if (n == NULL) { 1831 assert(i >= req() || i == 0 || is_Region() || is_Phi(), "only regions or phis have null data edges"); 1832 } else { 1833 assert(n->is_top(), "sanity"); 1834 // Nothing to check. 1835 } 1836 } 1837 // Recursive walk over all input edges 1838 for( i = 0; i < len(); i++ ) { 1839 n = in(i); 1840 if( n != NULL ) 1841 in(i)->verify_edges(visited); 1842 } 1843 } 1844 1845 //------------------------------verify_recur----------------------------------- 1846 static const Node *unique_top = NULL; 1847 1848 void Node::verify_recur(const Node *n, int verify_depth, 1849 VectorSet &old_space, VectorSet &new_space) { 1850 if ( verify_depth == 0 ) return; 1851 if (verify_depth > 0) --verify_depth; 1852 1853 Compile* C = Compile::current(); 1854 1855 // Contained in new_space or old_space? 1856 VectorSet *v = C->node_arena()->contains(n) ? &new_space : &old_space; 1857 // Check for visited in the proper space. Numberings are not unique 1858 // across spaces so we need a separate VectorSet for each space. 1859 if( v->test_set(n->_idx) ) return; 1860 1861 if (n->is_Con() && n->bottom_type() == Type::TOP) { 1862 if (C->cached_top_node() == NULL) 1863 C->set_cached_top_node((Node*)n); 1864 assert(C->cached_top_node() == n, "TOP node must be unique"); 1865 } 1866 1867 for( uint i = 0; i < n->len(); i++ ) { 1868 Node *x = n->in(i); 1869 if (!x || x->is_top()) continue; 1870 1871 // Verify my input has a def-use edge to me 1872 if (true /*VerifyDefUse*/) { 1873 // Count use-def edges from n to x 1874 int cnt = 0; 1875 for( uint j = 0; j < n->len(); j++ ) 1876 if( n->in(j) == x ) 1877 cnt++; 1878 // Count def-use edges from x to n 1879 uint max = x->_outcnt; 1880 for( uint k = 0; k < max; k++ ) 1881 if (x->_out[k] == n) 1882 cnt--; 1883 assert( cnt == 0, "mismatched def-use edge counts" ); 1884 } 1885 1886 verify_recur(x, verify_depth, old_space, new_space); 1887 } 1888 1889 } 1890 1891 //------------------------------verify----------------------------------------- 1892 // Check Def-Use info for my subgraph 1893 void Node::verify() const { 1894 Compile* C = Compile::current(); 1895 Node* old_top = C->cached_top_node(); 1896 ResourceMark rm; 1897 ResourceArea *area = Thread::current()->resource_area(); 1898 VectorSet old_space(area), new_space(area); 1899 verify_recur(this, -1, old_space, new_space); 1900 C->set_cached_top_node(old_top); 1901 } 1902 #endif 1903 1904 1905 //------------------------------walk------------------------------------------- 1906 // Graph walk, with both pre-order and post-order functions 1907 void Node::walk(NFunc pre, NFunc post, void *env) { 1908 VectorSet visited(Thread::current()->resource_area()); // Setup for local walk 1909 walk_(pre, post, env, visited); 1910 } 1911 1912 void Node::walk_(NFunc pre, NFunc post, void *env, VectorSet &visited) { 1913 if( visited.test_set(_idx) ) return; 1914 pre(*this,env); // Call the pre-order walk function 1915 for( uint i=0; i<_max; i++ ) 1916 if( in(i) ) // Input exists and is not walked? 1917 in(i)->walk_(pre,post,env,visited); // Walk it with pre & post functions 1918 post(*this,env); // Call the post-order walk function 1919 } 1920 1921 void Node::nop(Node &, void*) {} 1922 1923 //------------------------------Registers-------------------------------------- 1924 // Do we Match on this edge index or not? Generally false for Control 1925 // and true for everything else. Weird for calls & returns. 1926 uint Node::match_edge(uint idx) const { 1927 return idx; // True for other than index 0 (control) 1928 } 1929 1930 static RegMask _not_used_at_all; 1931 // Register classes are defined for specific machines 1932 const RegMask &Node::out_RegMask() const { 1933 ShouldNotCallThis(); 1934 return _not_used_at_all; 1935 } 1936 1937 const RegMask &Node::in_RegMask(uint) const { 1938 ShouldNotCallThis(); 1939 return _not_used_at_all; 1940 } 1941 1942 //============================================================================= 1943 //----------------------------------------------------------------------------- 1944 void Node_Array::reset( Arena *new_arena ) { 1945 _a->Afree(_nodes,_max*sizeof(Node*)); 1946 _max = 0; 1947 _nodes = NULL; 1948 _a = new_arena; 1949 } 1950 1951 //------------------------------clear------------------------------------------ 1952 // Clear all entries in _nodes to NULL but keep storage 1953 void Node_Array::clear() { 1954 Copy::zero_to_bytes( _nodes, _max*sizeof(Node*) ); 1955 } 1956 1957 //----------------------------------------------------------------------------- 1958 void Node_Array::grow( uint i ) { 1959 if( !_max ) { 1960 _max = 1; 1961 _nodes = (Node**)_a->Amalloc( _max * sizeof(Node*) ); 1962 _nodes[0] = NULL; 1963 } 1964 uint old = _max; 1965 while( i >= _max ) _max <<= 1; // Double to fit 1966 _nodes = (Node**)_a->Arealloc( _nodes, old*sizeof(Node*),_max*sizeof(Node*)); 1967 Copy::zero_to_bytes( &_nodes[old], (_max-old)*sizeof(Node*) ); 1968 } 1969 1970 //----------------------------------------------------------------------------- 1971 void Node_Array::insert( uint i, Node *n ) { 1972 if( _nodes[_max-1] ) grow(_max); // Get more space if full 1973 Copy::conjoint_words_to_higher((HeapWord*)&_nodes[i], (HeapWord*)&_nodes[i+1], ((_max-i-1)*sizeof(Node*))); 1974 _nodes[i] = n; 1975 } 1976 1977 //----------------------------------------------------------------------------- 1978 void Node_Array::remove( uint i ) { 1979 Copy::conjoint_words_to_lower((HeapWord*)&_nodes[i+1], (HeapWord*)&_nodes[i], ((_max-i-1)*sizeof(Node*))); 1980 _nodes[_max-1] = NULL; 1981 } 1982 1983 //----------------------------------------------------------------------------- 1984 void Node_Array::sort( C_sort_func_t func) { 1985 qsort( _nodes, _max, sizeof( Node* ), func ); 1986 } 1987 1988 //----------------------------------------------------------------------------- 1989 void Node_Array::dump() const { 1990 #ifndef PRODUCT 1991 for( uint i = 0; i < _max; i++ ) { 1992 Node *nn = _nodes[i]; 1993 if( nn != NULL ) { 1994 tty->print("%5d--> ",i); nn->dump(); 1995 } 1996 } 1997 #endif 1998 } 1999 2000 //--------------------------is_iteratively_computed------------------------------ 2001 // Operation appears to be iteratively computed (such as an induction variable) 2002 // It is possible for this operation to return false for a loop-varying 2003 // value, if it appears (by local graph inspection) to be computed by a simple conditional. 2004 bool Node::is_iteratively_computed() { 2005 if (ideal_reg()) { // does operation have a result register? 2006 for (uint i = 1; i < req(); i++) { 2007 Node* n = in(i); 2008 if (n != NULL && n->is_Phi()) { 2009 for (uint j = 1; j < n->req(); j++) { 2010 if (n->in(j) == this) { 2011 return true; 2012 } 2013 } 2014 } 2015 } 2016 } 2017 return false; 2018 } 2019 2020 //--------------------------find_similar------------------------------ 2021 // Return a node with opcode "opc" and same inputs as "this" if one can 2022 // be found; Otherwise return NULL; 2023 Node* Node::find_similar(int opc) { 2024 if (req() >= 2) { 2025 Node* def = in(1); 2026 if (def && def->outcnt() >= 2) { 2027 for (DUIterator_Fast dmax, i = def->fast_outs(dmax); i < dmax; i++) { 2028 Node* use = def->fast_out(i); 2029 if (use->Opcode() == opc && 2030 use->req() == req()) { 2031 uint j; 2032 for (j = 0; j < use->req(); j++) { 2033 if (use->in(j) != in(j)) { 2034 break; 2035 } 2036 } 2037 if (j == use->req()) { 2038 return use; 2039 } 2040 } 2041 } 2042 } 2043 } 2044 return NULL; 2045 } 2046 2047 2048 //--------------------------unique_ctrl_out------------------------------ 2049 // Return the unique control out if only one. Null if none or more than one. 2050 Node* Node::unique_ctrl_out() { 2051 Node* found = NULL; 2052 for (uint i = 0; i < outcnt(); i++) { 2053 Node* use = raw_out(i); 2054 if (use->is_CFG() && use != this) { 2055 if (found != NULL) return NULL; 2056 found = use; 2057 } 2058 } 2059 return found; 2060 } 2061 2062 //============================================================================= 2063 //------------------------------yank------------------------------------------- 2064 // Find and remove 2065 void Node_List::yank( Node *n ) { 2066 uint i; 2067 for( i = 0; i < _cnt; i++ ) 2068 if( _nodes[i] == n ) 2069 break; 2070 2071 if( i < _cnt ) 2072 _nodes[i] = _nodes[--_cnt]; 2073 } 2074 2075 //------------------------------dump------------------------------------------- 2076 void Node_List::dump() const { 2077 #ifndef PRODUCT 2078 for( uint i = 0; i < _cnt; i++ ) 2079 if( _nodes[i] ) { 2080 tty->print("%5d--> ",i); 2081 _nodes[i]->dump(); 2082 } 2083 #endif 2084 } 2085 2086 //============================================================================= 2087 //------------------------------remove----------------------------------------- 2088 void Unique_Node_List::remove( Node *n ) { 2089 if( _in_worklist[n->_idx] ) { 2090 for( uint i = 0; i < size(); i++ ) 2091 if( _nodes[i] == n ) { 2092 map(i,Node_List::pop()); 2093 _in_worklist >>= n->_idx; 2094 return; 2095 } 2096 ShouldNotReachHere(); 2097 } 2098 } 2099 2100 //-----------------------remove_useless_nodes---------------------------------- 2101 // Remove useless nodes from worklist 2102 void Unique_Node_List::remove_useless_nodes(VectorSet &useful) { 2103 2104 for( uint i = 0; i < size(); ++i ) { 2105 Node *n = at(i); 2106 assert( n != NULL, "Did not expect null entries in worklist"); 2107 if( ! useful.test(n->_idx) ) { 2108 _in_worklist >>= n->_idx; 2109 map(i,Node_List::pop()); 2110 // Node *replacement = Node_List::pop(); 2111 // if( i != size() ) { // Check if removing last entry 2112 // _nodes[i] = replacement; 2113 // } 2114 --i; // Visit popped node 2115 // If it was last entry, loop terminates since size() was also reduced 2116 } 2117 } 2118 } 2119 2120 //============================================================================= 2121 void Node_Stack::grow() { 2122 size_t old_top = pointer_delta(_inode_top,_inodes,sizeof(INode)); // save _top 2123 size_t old_max = pointer_delta(_inode_max,_inodes,sizeof(INode)); 2124 size_t max = old_max << 1; // max * 2 2125 _inodes = REALLOC_ARENA_ARRAY(_a, INode, _inodes, old_max, max); 2126 _inode_max = _inodes + max; 2127 _inode_top = _inodes + old_top; // restore _top 2128 } 2129 2130 // Node_Stack is used to map nodes. 2131 Node* Node_Stack::find(uint idx) const { 2132 uint sz = size(); 2133 for (uint i=0; i < sz; i++) { 2134 if (idx == index_at(i) ) 2135 return node_at(i); 2136 } 2137 return NULL; 2138 } 2139 2140 //============================================================================= 2141 uint TypeNode::size_of() const { return sizeof(*this); } 2142 #ifndef PRODUCT 2143 void TypeNode::dump_spec(outputStream *st) const { 2144 if( !Verbose && !WizardMode ) { 2145 // standard dump does this in Verbose and WizardMode 2146 st->print(" #"); _type->dump_on(st); 2147 } 2148 } 2149 #endif 2150 uint TypeNode::hash() const { 2151 return Node::hash() + _type->hash(); 2152 } 2153 uint TypeNode::cmp( const Node &n ) const 2154 { return !Type::cmp( _type, ((TypeNode&)n)._type ); } 2155 const Type *TypeNode::bottom_type() const { return _type; } 2156 const Type *TypeNode::Value( PhaseTransform * ) const { return _type; } 2157 2158 //------------------------------ideal_reg-------------------------------------- 2159 uint TypeNode::ideal_reg() const { 2160 return _type->ideal_reg(); 2161 }