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