1 /*
   2  * Copyright (c) 1997, 2022, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_OPTO_NODE_HPP
  26 #define SHARE_OPTO_NODE_HPP
  27 
  28 #include "libadt/vectset.hpp"
  29 #include "opto/compile.hpp"
  30 #include "opto/type.hpp"
  31 #include "utilities/copy.hpp"
  32 
  33 // Portions of code courtesy of Clifford Click
  34 
  35 // Optimization - Graph Style
  36 
  37 
  38 class AbstractLockNode;
  39 class AddNode;
  40 class AddPNode;
  41 class AliasInfo;
  42 class AllocateArrayNode;
  43 class AllocateNode;
  44 class ArrayCopyNode;
  45 class BaseCountedLoopNode;
  46 class BaseCountedLoopEndNode;
  47 class BlackholeNode;
  48 class Block;
  49 class BoolNode;
  50 class BoxLockNode;
  51 class CMoveNode;
  52 class CallDynamicJavaNode;
  53 class CallJavaNode;
  54 class CallLeafNode;
  55 class CallLeafNoFPNode;
  56 class CallNode;
  57 class CallRuntimeNode;
  58 class CallNativeNode;
  59 class CallStaticJavaNode;
  60 class CastFFNode;
  61 class CastDDNode;
  62 class CastVVNode;
  63 class CastIINode;
  64 class CastLLNode;
  65 class CatchNode;
  66 class CatchProjNode;
  67 class CheckCastPPNode;
  68 class ClearArrayNode;
  69 class CmpNode;
  70 class CodeBuffer;
  71 class ConstraintCastNode;
  72 class ConNode;
  73 class CompareAndSwapNode;
  74 class CompareAndExchangeNode;
  75 class CountedLoopNode;
  76 class CountedLoopEndNode;
  77 class DecodeNarrowPtrNode;
  78 class DecodeNNode;
  79 class DecodeNKlassNode;
  80 class EncodeNarrowPtrNode;
  81 class EncodePNode;
  82 class EncodePKlassNode;
  83 class FastLockNode;
  84 class FastUnlockNode;
  85 class HaltNode;
  86 class IfNode;
  87 class IfProjNode;
  88 class IfFalseNode;
  89 class IfTrueNode;
  90 class InitializeNode;
  91 class JVMState;
  92 class JumpNode;
  93 class JumpProjNode;
  94 class LoadNode;
  95 class LoadStoreNode;
  96 class LoadStoreConditionalNode;
  97 class LockNode;
  98 class LongCountedLoopNode;
  99 class LongCountedLoopEndNode;
 100 class LoopNode;
 101 class LShiftNode;
 102 class MachBranchNode;
 103 class MachCallDynamicJavaNode;
 104 class MachCallJavaNode;
 105 class MachCallLeafNode;
 106 class MachCallNode;
 107 class MachCallNativeNode;
 108 class MachCallRuntimeNode;
 109 class MachCallStaticJavaNode;
 110 class MachConstantBaseNode;
 111 class MachConstantNode;
 112 class MachGotoNode;
 113 class MachIfNode;
 114 class MachJumpNode;
 115 class MachNode;
 116 class MachNullCheckNode;
 117 class MachProjNode;
 118 class MachReturnNode;
 119 class MachSafePointNode;
 120 class MachSpillCopyNode;
 121 class MachTempNode;
 122 class MachMergeNode;
 123 class MachMemBarNode;
 124 class Matcher;
 125 class MemBarNode;
 126 class MemBarStoreStoreNode;
 127 class MemNode;
 128 class MergeMemNode;
 129 class MoveNode;
 130 class MulNode;
 131 class MultiNode;
 132 class MultiBranchNode;
 133 class NeverBranchNode;
 134 class Opaque1Node;
 135 class OuterStripMinedLoopNode;
 136 class OuterStripMinedLoopEndNode;
 137 class Node;
 138 class Node_Array;
 139 class Node_List;
 140 class Node_Stack;
 141 class OopMap;
 142 class ParmNode;
 143 class PCTableNode;
 144 class PhaseCCP;
 145 class PhaseGVN;
 146 class PhaseIterGVN;
 147 class PhaseRegAlloc;
 148 class PhaseTransform;
 149 class PhaseValues;
 150 class PhiNode;
 151 class Pipeline;
 152 class ProjNode;
 153 class RangeCheckNode;
 154 class RegMask;
 155 class RegionNode;
 156 class RootNode;
 157 class SafePointNode;
 158 class SafePointScalarObjectNode;
 159 class StartNode;
 160 class State;
 161 class StoreNode;
 162 class SubNode;
 163 class SubTypeCheckNode;
 164 class Type;
 165 class TypeNode;
 166 class UnlockNode;
 167 class VectorNode;
 168 class LoadVectorNode;
 169 class LoadVectorMaskedNode;
 170 class StoreVectorMaskedNode;
 171 class LoadVectorGatherNode;
 172 class StoreVectorNode;
 173 class StoreVectorScatterNode;
 174 class VectorMaskCmpNode;
 175 class VectorUnboxNode;
 176 class VectorSet;
 177 class VectorReinterpretNode;
 178 class ShiftVNode;



 179 
 180 
 181 #ifndef OPTO_DU_ITERATOR_ASSERT
 182 #ifdef ASSERT
 183 #define OPTO_DU_ITERATOR_ASSERT 1
 184 #else
 185 #define OPTO_DU_ITERATOR_ASSERT 0
 186 #endif
 187 #endif //OPTO_DU_ITERATOR_ASSERT
 188 
 189 #if OPTO_DU_ITERATOR_ASSERT
 190 class DUIterator;
 191 class DUIterator_Fast;
 192 class DUIterator_Last;
 193 #else
 194 typedef uint   DUIterator;
 195 typedef Node** DUIterator_Fast;
 196 typedef Node** DUIterator_Last;
 197 #endif
 198 
 199 // Node Sentinel
 200 #define NodeSentinel (Node*)-1
 201 
 202 // Unknown count frequency
 203 #define COUNT_UNKNOWN (-1.0f)
 204 
 205 //------------------------------Node-------------------------------------------
 206 // Nodes define actions in the program.  They create values, which have types.
 207 // They are both vertices in a directed graph and program primitives.  Nodes
 208 // are labeled; the label is the "opcode", the primitive function in the lambda
 209 // calculus sense that gives meaning to the Node.  Node inputs are ordered (so
 210 // that "a-b" is different from "b-a").  The inputs to a Node are the inputs to
 211 // the Node's function.  These inputs also define a Type equation for the Node.
 212 // Solving these Type equations amounts to doing dataflow analysis.
 213 // Control and data are uniformly represented in the graph.  Finally, Nodes
 214 // have a unique dense integer index which is used to index into side arrays
 215 // whenever I have phase-specific information.
 216 
 217 class Node {
 218   friend class VMStructs;
 219 
 220   // Lots of restrictions on cloning Nodes
 221   NONCOPYABLE(Node);
 222 
 223 public:
 224   friend class Compile;
 225   #if OPTO_DU_ITERATOR_ASSERT
 226   friend class DUIterator_Common;
 227   friend class DUIterator;
 228   friend class DUIterator_Fast;
 229   friend class DUIterator_Last;
 230   #endif
 231 
 232   // Because Nodes come and go, I define an Arena of Node structures to pull
 233   // from.  This should allow fast access to node creation & deletion.  This
 234   // field is a local cache of a value defined in some "program fragment" for
 235   // which these Nodes are just a part of.
 236 
 237   inline void* operator new(size_t x) throw() {
 238     Compile* C = Compile::current();
 239     Node* n = (Node*)C->node_arena()->AmallocWords(x);
 240     return (void*)n;
 241   }
 242 
 243   // Delete is a NOP
 244   void operator delete( void *ptr ) {}
 245   // Fancy destructor; eagerly attempt to reclaim Node numberings and storage
 246   void destruct(PhaseValues* phase);
 247 
 248   // Create a new Node.  Required is the number is of inputs required for
 249   // semantic correctness.
 250   Node( uint required );
 251 
 252   // Create a new Node with given input edges.
 253   // This version requires use of the "edge-count" new.
 254   // E.g.  new (C,3) FooNode( C, NULL, left, right );
 255   Node( Node *n0 );
 256   Node( Node *n0, Node *n1 );
 257   Node( Node *n0, Node *n1, Node *n2 );
 258   Node( Node *n0, Node *n1, Node *n2, Node *n3 );
 259   Node( Node *n0, Node *n1, Node *n2, Node *n3, Node *n4 );
 260   Node( Node *n0, Node *n1, Node *n2, Node *n3, Node *n4, Node *n5 );
 261   Node( Node *n0, Node *n1, Node *n2, Node *n3,
 262             Node *n4, Node *n5, Node *n6 );
 263 
 264   // Clone an inherited Node given only the base Node type.
 265   Node* clone() const;
 266 
 267   // Clone a Node, immediately supplying one or two new edges.
 268   // The first and second arguments, if non-null, replace in(1) and in(2),
 269   // respectively.
 270   Node* clone_with_data_edge(Node* in1, Node* in2 = NULL) const {
 271     Node* nn = clone();
 272     if (in1 != NULL)  nn->set_req(1, in1);
 273     if (in2 != NULL)  nn->set_req(2, in2);
 274     return nn;
 275   }
 276 
 277 private:
 278   // Shared setup for the above constructors.
 279   // Handles all interactions with Compile::current.
 280   // Puts initial values in all Node fields except _idx.
 281   // Returns the initial value for _idx, which cannot
 282   // be initialized by assignment.
 283   inline int Init(int req);
 284 
 285 //----------------- input edge handling
 286 protected:
 287   friend class PhaseCFG;        // Access to address of _in array elements
 288   Node **_in;                   // Array of use-def references to Nodes
 289   Node **_out;                  // Array of def-use references to Nodes
 290 
 291   // Input edges are split into two categories.  Required edges are required
 292   // for semantic correctness; order is important and NULLs are allowed.
 293   // Precedence edges are used to help determine execution order and are
 294   // added, e.g., for scheduling purposes.  They are unordered and not
 295   // duplicated; they have no embedded NULLs.  Edges from 0 to _cnt-1
 296   // are required, from _cnt to _max-1 are precedence edges.
 297   node_idx_t _cnt;              // Total number of required Node inputs.
 298 
 299   node_idx_t _max;              // Actual length of input array.
 300 
 301   // Output edges are an unordered list of def-use edges which exactly
 302   // correspond to required input edges which point from other nodes
 303   // to this one.  Thus the count of the output edges is the number of
 304   // users of this node.
 305   node_idx_t _outcnt;           // Total number of Node outputs.
 306 
 307   node_idx_t _outmax;           // Actual length of output array.
 308 
 309   // Grow the actual input array to the next larger power-of-2 bigger than len.
 310   void grow( uint len );
 311   // Grow the output array to the next larger power-of-2 bigger than len.
 312   void out_grow( uint len );
 313 
 314  public:
 315   // Each Node is assigned a unique small/dense number.  This number is used
 316   // to index into auxiliary arrays of data and bit vectors.
 317   // The field _idx is declared constant to defend against inadvertent assignments,
 318   // since it is used by clients as a naked field. However, the field's value can be
 319   // changed using the set_idx() method.
 320   //
 321   // The PhaseRenumberLive phase renumbers nodes based on liveness information.
 322   // Therefore, it updates the value of the _idx field. The parse-time _idx is
 323   // preserved in _parse_idx.
 324   const node_idx_t _idx;
 325   DEBUG_ONLY(const node_idx_t _parse_idx;)
 326   // IGV node identifier. Two nodes, possibly in different compilation phases,
 327   // have the same IGV identifier if (and only if) they are the very same node
 328   // (same memory address) or one is "derived" from the other (by e.g.
 329   // renumbering or matching). This identifier makes it possible to follow the
 330   // entire lifetime of a node in IGV even if its C2 identifier (_idx) changes.
 331   NOT_PRODUCT(node_idx_t _igv_idx;)
 332 
 333   // Get the (read-only) number of input edges
 334   uint req() const { return _cnt; }
 335   uint len() const { return _max; }
 336   // Get the (read-only) number of output edges
 337   uint outcnt() const { return _outcnt; }
 338 
 339 #if OPTO_DU_ITERATOR_ASSERT
 340   // Iterate over the out-edges of this node.  Deletions are illegal.
 341   inline DUIterator outs() const;
 342   // Use this when the out array might have changed to suppress asserts.
 343   inline DUIterator& refresh_out_pos(DUIterator& i) const;
 344   // Does the node have an out at this position?  (Used for iteration.)
 345   inline bool has_out(DUIterator& i) const;
 346   inline Node*    out(DUIterator& i) const;
 347   // Iterate over the out-edges of this node.  All changes are illegal.
 348   inline DUIterator_Fast fast_outs(DUIterator_Fast& max) const;
 349   inline Node*    fast_out(DUIterator_Fast& i) const;
 350   // Iterate over the out-edges of this node, deleting one at a time.
 351   inline DUIterator_Last last_outs(DUIterator_Last& min) const;
 352   inline Node*    last_out(DUIterator_Last& i) const;
 353   // The inline bodies of all these methods are after the iterator definitions.
 354 #else
 355   // Iterate over the out-edges of this node.  Deletions are illegal.
 356   // This iteration uses integral indexes, to decouple from array reallocations.
 357   DUIterator outs() const  { return 0; }
 358   // Use this when the out array might have changed to suppress asserts.
 359   DUIterator refresh_out_pos(DUIterator i) const { return i; }
 360 
 361   // Reference to the i'th output Node.  Error if out of bounds.
 362   Node*    out(DUIterator i) const { assert(i < _outcnt, "oob"); return _out[i]; }
 363   // Does the node have an out at this position?  (Used for iteration.)
 364   bool has_out(DUIterator i) const { return i < _outcnt; }
 365 
 366   // Iterate over the out-edges of this node.  All changes are illegal.
 367   // This iteration uses a pointer internal to the out array.
 368   DUIterator_Fast fast_outs(DUIterator_Fast& max) const {
 369     Node** out = _out;
 370     // Assign a limit pointer to the reference argument:
 371     max = out + (ptrdiff_t)_outcnt;
 372     // Return the base pointer:
 373     return out;
 374   }
 375   Node*    fast_out(DUIterator_Fast i) const  { return *i; }
 376   // Iterate over the out-edges of this node, deleting one at a time.
 377   // This iteration uses a pointer internal to the out array.
 378   DUIterator_Last last_outs(DUIterator_Last& min) const {
 379     Node** out = _out;
 380     // Assign a limit pointer to the reference argument:
 381     min = out;
 382     // Return the pointer to the start of the iteration:
 383     return out + (ptrdiff_t)_outcnt - 1;
 384   }
 385   Node*    last_out(DUIterator_Last i) const  { return *i; }
 386 #endif
 387 
 388   // Reference to the i'th input Node.  Error if out of bounds.
 389   Node* in(uint i) const { assert(i < _max, "oob: i=%d, _max=%d", i, _max); return _in[i]; }
 390   // Reference to the i'th input Node.  NULL if out of bounds.
 391   Node* lookup(uint i) const { return ((i < _max) ? _in[i] : NULL); }
 392   // Reference to the i'th output Node.  Error if out of bounds.
 393   // Use this accessor sparingly.  We are going trying to use iterators instead.
 394   Node* raw_out(uint i) const { assert(i < _outcnt,"oob"); return _out[i]; }
 395   // Return the unique out edge.
 396   Node* unique_out() const { assert(_outcnt==1,"not unique"); return _out[0]; }
 397   // Delete out edge at position 'i' by moving last out edge to position 'i'
 398   void  raw_del_out(uint i) {
 399     assert(i < _outcnt,"oob");
 400     assert(_outcnt > 0,"oob");
 401     #if OPTO_DU_ITERATOR_ASSERT
 402     // Record that a change happened here.
 403     debug_only(_last_del = _out[i]; ++_del_tick);
 404     #endif
 405     _out[i] = _out[--_outcnt];
 406     // Smash the old edge so it can't be used accidentally.
 407     debug_only(_out[_outcnt] = (Node *)(uintptr_t)0xdeadbeef);
 408   }
 409 
 410 #ifdef ASSERT
 411   bool is_dead() const;
 412 #define is_not_dead(n) ((n) == NULL || !VerifyIterativeGVN || !((n)->is_dead()))
 413   bool is_reachable_from_root() const;
 414 #endif
 415   // Check whether node has become unreachable
 416   bool is_unreachable(PhaseIterGVN &igvn) const;
 417 
 418   // Set a required input edge, also updates corresponding output edge
 419   void add_req( Node *n ); // Append a NEW required input
 420   void add_req( Node *n0, Node *n1 ) {
 421     add_req(n0); add_req(n1); }
 422   void add_req( Node *n0, Node *n1, Node *n2 ) {
 423     add_req(n0); add_req(n1); add_req(n2); }
 424   void add_req_batch( Node* n, uint m ); // Append m NEW required inputs (all n).
 425   void del_req( uint idx ); // Delete required edge & compact
 426   void del_req_ordered( uint idx ); // Delete required edge & compact with preserved order
 427   void ins_req( uint i, Node *n ); // Insert a NEW required input
 428   void set_req( uint i, Node *n ) {
 429     assert( is_not_dead(n), "can not use dead node");
 430     assert( i < _cnt, "oob: i=%d, _cnt=%d", i, _cnt);
 431     assert( !VerifyHashTableKeys || _hash_lock == 0,
 432             "remove node from hash table before modifying it");
 433     Node** p = &_in[i];    // cache this._in, across the del_out call
 434     if (*p != NULL)  (*p)->del_out((Node *)this);
 435     (*p) = n;
 436     if (n != NULL)      n->add_out((Node *)this);
 437     Compile::current()->record_modified_node(this);
 438   }
 439   // Light version of set_req() to init inputs after node creation.
 440   void init_req( uint i, Node *n ) {
 441     assert( i == 0 && this == n ||
 442             is_not_dead(n), "can not use dead node");
 443     assert( i < _cnt, "oob");
 444     assert( !VerifyHashTableKeys || _hash_lock == 0,
 445             "remove node from hash table before modifying it");
 446     assert( _in[i] == NULL, "sanity");
 447     _in[i] = n;
 448     if (n != NULL)      n->add_out((Node *)this);
 449     Compile::current()->record_modified_node(this);
 450   }
 451   // Find first occurrence of n among my edges:
 452   int find_edge(Node* n);
 453   int find_prec_edge(Node* n) {
 454     for (uint i = req(); i < len(); i++) {
 455       if (_in[i] == n) return i;
 456       if (_in[i] == NULL) {
 457         DEBUG_ONLY( while ((++i) < len()) assert(_in[i] == NULL, "Gap in prec edges!"); )
 458         break;
 459       }
 460     }
 461     return -1;
 462   }
 463   int replace_edge(Node* old, Node* neww, PhaseGVN* gvn = NULL);
 464   int replace_edges_in_range(Node* old, Node* neww, int start, int end, PhaseGVN* gvn);
 465   // NULL out all inputs to eliminate incoming Def-Use edges.
 466   void disconnect_inputs(Compile* C);
 467 
 468   // Quickly, return true if and only if I am Compile::current()->top().
 469   bool is_top() const {
 470     assert((this == (Node*) Compile::current()->top()) == (_out == NULL), "");
 471     return (_out == NULL);
 472   }
 473   // Reaffirm invariants for is_top.  (Only from Compile::set_cached_top_node.)
 474   void setup_is_top();
 475 
 476   // Strip away casting.  (It is depth-limited.)
 477   Node* uncast(bool keep_deps = false) const;
 478   // Return whether two Nodes are equivalent, after stripping casting.
 479   bool eqv_uncast(const Node* n, bool keep_deps = false) const {
 480     return (this->uncast(keep_deps) == n->uncast(keep_deps));
 481   }
 482 
 483   // Find out of current node that matches opcode.
 484   Node* find_out_with(int opcode);
 485   // Return true if the current node has an out that matches opcode.
 486   bool has_out_with(int opcode);
 487   // Return true if the current node has an out that matches any of the opcodes.
 488   bool has_out_with(int opcode1, int opcode2, int opcode3, int opcode4);
 489 
 490 private:
 491   static Node* uncast_helper(const Node* n, bool keep_deps);
 492 
 493   // Add an output edge to the end of the list
 494   void add_out( Node *n ) {
 495     if (is_top())  return;
 496     if( _outcnt == _outmax ) out_grow(_outcnt);
 497     _out[_outcnt++] = n;
 498   }
 499   // Delete an output edge
 500   void del_out( Node *n ) {
 501     if (is_top())  return;
 502     Node** outp = &_out[_outcnt];
 503     // Find and remove n
 504     do {
 505       assert(outp > _out, "Missing Def-Use edge");
 506     } while (*--outp != n);
 507     *outp = _out[--_outcnt];
 508     // Smash the old edge so it can't be used accidentally.
 509     debug_only(_out[_outcnt] = (Node *)(uintptr_t)0xdeadbeef);
 510     // Record that a change happened here.
 511     #if OPTO_DU_ITERATOR_ASSERT
 512     debug_only(_last_del = n; ++_del_tick);
 513     #endif
 514   }
 515   // Close gap after removing edge.
 516   void close_prec_gap_at(uint gap) {
 517     assert(_cnt <= gap && gap < _max, "no valid prec edge");
 518     uint i = gap;
 519     Node *last = NULL;
 520     for (; i < _max-1; ++i) {
 521       Node *next = _in[i+1];
 522       if (next == NULL) break;
 523       last = next;
 524     }
 525     _in[gap] = last; // Move last slot to empty one.
 526     _in[i] = NULL;   // NULL out last slot.
 527   }
 528 
 529 public:
 530   // Globally replace this node by a given new node, updating all uses.
 531   void replace_by(Node* new_node);
 532   // Globally replace this node by a given new node, updating all uses
 533   // and cutting input edges of old node.
 534   void subsume_by(Node* new_node, Compile* c) {
 535     replace_by(new_node);
 536     disconnect_inputs(c);
 537   }
 538   void set_req_X(uint i, Node *n, PhaseIterGVN *igvn);
 539   void set_req_X(uint i, Node *n, PhaseGVN *gvn);
 540   // Find the one non-null required input.  RegionNode only
 541   Node *nonnull_req() const;
 542   // Add or remove precedence edges
 543   void add_prec( Node *n );
 544   void rm_prec( uint i );
 545 
 546   // Note: prec(i) will not necessarily point to n if edge already exists.
 547   void set_prec( uint i, Node *n ) {
 548     assert(i < _max, "oob: i=%d, _max=%d", i, _max);
 549     assert(is_not_dead(n), "can not use dead node");
 550     assert(i >= _cnt, "not a precedence edge");
 551     // Avoid spec violation: duplicated prec edge.
 552     if (_in[i] == n) return;
 553     if (n == NULL || find_prec_edge(n) != -1) {
 554       rm_prec(i);
 555       return;
 556     }
 557     if (_in[i] != NULL) _in[i]->del_out((Node *)this);
 558     _in[i] = n;
 559     n->add_out((Node *)this);
 560   }
 561 
 562   // Set this node's index, used by cisc_version to replace current node
 563   void set_idx(uint new_idx) {
 564     const node_idx_t* ref = &_idx;
 565     *(node_idx_t*)ref = new_idx;
 566   }
 567   // Swap input edge order.  (Edge indexes i1 and i2 are usually 1 and 2.)
 568   void swap_edges(uint i1, uint i2) {
 569     debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
 570     // Def-Use info is unchanged
 571     Node* n1 = in(i1);
 572     Node* n2 = in(i2);
 573     _in[i1] = n2;
 574     _in[i2] = n1;
 575     // If this node is in the hash table, make sure it doesn't need a rehash.
 576     assert(check_hash == NO_HASH || check_hash == hash(), "edge swap must preserve hash code");
 577   }
 578 
 579   // Iterators over input Nodes for a Node X are written as:
 580   // for( i = 0; i < X.req(); i++ ) ... X[i] ...
 581   // NOTE: Required edges can contain embedded NULL pointers.
 582 
 583 //----------------- Other Node Properties
 584 
 585   // Generate class IDs for (some) ideal nodes so that it is possible to determine
 586   // the type of a node using a non-virtual method call (the method is_<Node>() below).
 587   //
 588   // A class ID of an ideal node is a set of bits. In a class ID, a single bit determines
 589   // the type of the node the ID represents; another subset of an ID's bits are reserved
 590   // for the superclasses of the node represented by the ID.
 591   //
 592   // By design, if A is a supertype of B, A.is_B() returns true and B.is_A()
 593   // returns false. A.is_A() returns true.
 594   //
 595   // If two classes, A and B, have the same superclass, a different bit of A's class id
 596   // is reserved for A's type than for B's type. That bit is specified by the third
 597   // parameter in the macro DEFINE_CLASS_ID.
 598   //
 599   // By convention, classes with deeper hierarchy are declared first. Moreover,
 600   // classes with the same hierarchy depth are sorted by usage frequency.
 601   //
 602   // The query method masks the bits to cut off bits of subclasses and then compares
 603   // the result with the class id (see the macro DEFINE_CLASS_QUERY below).
 604   //
 605   //  Class_MachCall=30, ClassMask_MachCall=31
 606   // 12               8               4               0
 607   //  0   0   0   0   0   0   0   0   1   1   1   1   0
 608   //                                  |   |   |   |
 609   //                                  |   |   |   Bit_Mach=2
 610   //                                  |   |   Bit_MachReturn=4
 611   //                                  |   Bit_MachSafePoint=8
 612   //                                  Bit_MachCall=16
 613   //
 614   //  Class_CountedLoop=56, ClassMask_CountedLoop=63
 615   // 12               8               4               0
 616   //  0   0   0   0   0   0   0   1   1   1   0   0   0
 617   //                              |   |   |
 618   //                              |   |   Bit_Region=8
 619   //                              |   Bit_Loop=16
 620   //                              Bit_CountedLoop=32
 621 
 622   #define DEFINE_CLASS_ID(cl, supcl, subn) \
 623   Bit_##cl = (Class_##supcl == 0) ? 1 << subn : (Bit_##supcl) << (1 + subn) , \
 624   Class_##cl = Class_##supcl + Bit_##cl , \
 625   ClassMask_##cl = ((Bit_##cl << 1) - 1) ,
 626 
 627   // This enum is used only for C2 ideal and mach nodes with is_<node>() methods
 628   // so that its values fit into 32 bits.
 629   enum NodeClasses {
 630     Bit_Node   = 0x00000000,
 631     Class_Node = 0x00000000,
 632     ClassMask_Node = 0xFFFFFFFF,
 633 
 634     DEFINE_CLASS_ID(Multi, Node, 0)
 635       DEFINE_CLASS_ID(SafePoint, Multi, 0)
 636         DEFINE_CLASS_ID(Call,      SafePoint, 0)
 637           DEFINE_CLASS_ID(CallJava,         Call, 0)
 638             DEFINE_CLASS_ID(CallStaticJava,   CallJava, 0)
 639             DEFINE_CLASS_ID(CallDynamicJava,  CallJava, 1)
 640           DEFINE_CLASS_ID(CallRuntime,      Call, 1)
 641             DEFINE_CLASS_ID(CallLeaf,         CallRuntime, 0)
 642               DEFINE_CLASS_ID(CallLeafNoFP,     CallLeaf, 0)
 643           DEFINE_CLASS_ID(Allocate,         Call, 2)
 644             DEFINE_CLASS_ID(AllocateArray,    Allocate, 0)
 645           DEFINE_CLASS_ID(AbstractLock,     Call, 3)
 646             DEFINE_CLASS_ID(Lock,             AbstractLock, 0)
 647             DEFINE_CLASS_ID(Unlock,           AbstractLock, 1)
 648           DEFINE_CLASS_ID(ArrayCopy,        Call, 4)
 649           DEFINE_CLASS_ID(CallNative,       Call, 5)
 650       DEFINE_CLASS_ID(MultiBranch, Multi, 1)
 651         DEFINE_CLASS_ID(PCTable,     MultiBranch, 0)
 652           DEFINE_CLASS_ID(Catch,       PCTable, 0)
 653           DEFINE_CLASS_ID(Jump,        PCTable, 1)
 654         DEFINE_CLASS_ID(If,          MultiBranch, 1)
 655           DEFINE_CLASS_ID(BaseCountedLoopEnd,     If, 0)
 656             DEFINE_CLASS_ID(CountedLoopEnd,       BaseCountedLoopEnd, 0)
 657             DEFINE_CLASS_ID(LongCountedLoopEnd,   BaseCountedLoopEnd, 1)
 658           DEFINE_CLASS_ID(RangeCheck,             If, 1)
 659           DEFINE_CLASS_ID(OuterStripMinedLoopEnd, If, 2)
 660         DEFINE_CLASS_ID(NeverBranch, MultiBranch, 2)
 661       DEFINE_CLASS_ID(Start,       Multi, 2)
 662       DEFINE_CLASS_ID(MemBar,      Multi, 3)
 663         DEFINE_CLASS_ID(Initialize,       MemBar, 0)
 664         DEFINE_CLASS_ID(MemBarStoreStore, MemBar, 1)
 665 
 666     DEFINE_CLASS_ID(Mach,  Node, 1)
 667       DEFINE_CLASS_ID(MachReturn, Mach, 0)
 668         DEFINE_CLASS_ID(MachSafePoint, MachReturn, 0)
 669           DEFINE_CLASS_ID(MachCall, MachSafePoint, 0)
 670             DEFINE_CLASS_ID(MachCallJava,         MachCall, 0)
 671               DEFINE_CLASS_ID(MachCallStaticJava,   MachCallJava, 0)
 672               DEFINE_CLASS_ID(MachCallDynamicJava,  MachCallJava, 1)
 673             DEFINE_CLASS_ID(MachCallRuntime,      MachCall, 1)
 674               DEFINE_CLASS_ID(MachCallLeaf,         MachCallRuntime, 0)
 675             DEFINE_CLASS_ID(MachCallNative,       MachCall, 2)
 676       DEFINE_CLASS_ID(MachBranch, Mach, 1)
 677         DEFINE_CLASS_ID(MachIf,         MachBranch, 0)
 678         DEFINE_CLASS_ID(MachGoto,       MachBranch, 1)
 679         DEFINE_CLASS_ID(MachNullCheck,  MachBranch, 2)
 680       DEFINE_CLASS_ID(MachSpillCopy,    Mach, 2)
 681       DEFINE_CLASS_ID(MachTemp,         Mach, 3)
 682       DEFINE_CLASS_ID(MachConstantBase, Mach, 4)
 683       DEFINE_CLASS_ID(MachConstant,     Mach, 5)
 684         DEFINE_CLASS_ID(MachJump,       MachConstant, 0)
 685       DEFINE_CLASS_ID(MachMerge,        Mach, 6)
 686       DEFINE_CLASS_ID(MachMemBar,       Mach, 7)
 687 
 688     DEFINE_CLASS_ID(Type,  Node, 2)
 689       DEFINE_CLASS_ID(Phi,   Type, 0)
 690       DEFINE_CLASS_ID(ConstraintCast, Type, 1)
 691         DEFINE_CLASS_ID(CastII, ConstraintCast, 0)
 692         DEFINE_CLASS_ID(CheckCastPP, ConstraintCast, 1)
 693         DEFINE_CLASS_ID(CastLL, ConstraintCast, 2)
 694         DEFINE_CLASS_ID(CastFF, ConstraintCast, 3)
 695         DEFINE_CLASS_ID(CastDD, ConstraintCast, 4)
 696         DEFINE_CLASS_ID(CastVV, ConstraintCast, 5)
 697       DEFINE_CLASS_ID(CMove, Type, 3)
 698       DEFINE_CLASS_ID(SafePointScalarObject, Type, 4)
 699       DEFINE_CLASS_ID(DecodeNarrowPtr, Type, 5)
 700         DEFINE_CLASS_ID(DecodeN, DecodeNarrowPtr, 0)
 701         DEFINE_CLASS_ID(DecodeNKlass, DecodeNarrowPtr, 1)
 702       DEFINE_CLASS_ID(EncodeNarrowPtr, Type, 6)
 703         DEFINE_CLASS_ID(EncodeP, EncodeNarrowPtr, 0)
 704         DEFINE_CLASS_ID(EncodePKlass, EncodeNarrowPtr, 1)
 705       DEFINE_CLASS_ID(Vector, Type, 7)
 706         DEFINE_CLASS_ID(VectorMaskCmp, Vector, 0)
 707         DEFINE_CLASS_ID(VectorUnbox, Vector, 1)
 708         DEFINE_CLASS_ID(VectorReinterpret, Vector, 2)
 709         DEFINE_CLASS_ID(ShiftV, Vector, 3)



 710 
 711     DEFINE_CLASS_ID(Proj,  Node, 3)
 712       DEFINE_CLASS_ID(CatchProj, Proj, 0)
 713       DEFINE_CLASS_ID(JumpProj,  Proj, 1)
 714       DEFINE_CLASS_ID(IfProj,    Proj, 2)
 715         DEFINE_CLASS_ID(IfTrue,    IfProj, 0)
 716         DEFINE_CLASS_ID(IfFalse,   IfProj, 1)
 717       DEFINE_CLASS_ID(Parm,      Proj, 4)
 718       DEFINE_CLASS_ID(MachProj,  Proj, 5)
 719 
 720     DEFINE_CLASS_ID(Mem, Node, 4)
 721       DEFINE_CLASS_ID(Load, Mem, 0)
 722         DEFINE_CLASS_ID(LoadVector,  Load, 0)
 723           DEFINE_CLASS_ID(LoadVectorGather, LoadVector, 0)
 724           DEFINE_CLASS_ID(LoadVectorMasked, LoadVector, 1)
 725       DEFINE_CLASS_ID(Store, Mem, 1)
 726         DEFINE_CLASS_ID(StoreVector, Store, 0)
 727           DEFINE_CLASS_ID(StoreVectorScatter, StoreVector, 0)
 728           DEFINE_CLASS_ID(StoreVectorMasked, StoreVector, 1)
 729       DEFINE_CLASS_ID(LoadStore, Mem, 2)
 730         DEFINE_CLASS_ID(LoadStoreConditional, LoadStore, 0)
 731           DEFINE_CLASS_ID(CompareAndSwap, LoadStoreConditional, 0)
 732         DEFINE_CLASS_ID(CompareAndExchangeNode, LoadStore, 1)
 733 
 734     DEFINE_CLASS_ID(Region, Node, 5)
 735       DEFINE_CLASS_ID(Loop, Region, 0)
 736         DEFINE_CLASS_ID(Root,                Loop, 0)
 737         DEFINE_CLASS_ID(BaseCountedLoop,     Loop, 1)
 738           DEFINE_CLASS_ID(CountedLoop,       BaseCountedLoop, 0)
 739           DEFINE_CLASS_ID(LongCountedLoop,   BaseCountedLoop, 1)
 740         DEFINE_CLASS_ID(OuterStripMinedLoop, Loop, 2)
 741 
 742     DEFINE_CLASS_ID(Sub,   Node, 6)
 743       DEFINE_CLASS_ID(Cmp,   Sub, 0)
 744         DEFINE_CLASS_ID(FastLock,   Cmp, 0)
 745         DEFINE_CLASS_ID(FastUnlock, Cmp, 1)
 746         DEFINE_CLASS_ID(SubTypeCheck,Cmp, 2)
 747 
 748     DEFINE_CLASS_ID(MergeMem, Node, 7)
 749     DEFINE_CLASS_ID(Bool,     Node, 8)
 750     DEFINE_CLASS_ID(AddP,     Node, 9)
 751     DEFINE_CLASS_ID(BoxLock,  Node, 10)
 752     DEFINE_CLASS_ID(Add,      Node, 11)
 753     DEFINE_CLASS_ID(Mul,      Node, 12)
 754     DEFINE_CLASS_ID(ClearArray, Node, 14)
 755     DEFINE_CLASS_ID(Halt,     Node, 15)
 756     DEFINE_CLASS_ID(Opaque1,  Node, 16)
 757     DEFINE_CLASS_ID(Move,     Node, 17)
 758     DEFINE_CLASS_ID(LShift,   Node, 18)
 759 
 760     _max_classes  = ClassMask_Move
 761   };
 762   #undef DEFINE_CLASS_ID
 763 
 764   // Flags are sorted by usage frequency.
 765   enum NodeFlags {
 766     Flag_is_Copy                     = 1 << 0, // should be first bit to avoid shift
 767     Flag_rematerialize               = 1 << 1,
 768     Flag_needs_anti_dependence_check = 1 << 2,
 769     Flag_is_macro                    = 1 << 3,
 770     Flag_is_Con                      = 1 << 4,
 771     Flag_is_cisc_alternate           = 1 << 5,
 772     Flag_is_dead_loop_safe           = 1 << 6,
 773     Flag_may_be_short_branch         = 1 << 7,
 774     Flag_avoid_back_to_back_before   = 1 << 8,
 775     Flag_avoid_back_to_back_after    = 1 << 9,
 776     Flag_has_call                    = 1 << 10,
 777     Flag_is_reduction                = 1 << 11,
 778     Flag_is_scheduled                = 1 << 12,
 779     Flag_is_expensive                = 1 << 13,
 780     Flag_is_predicated_vector        = 1 << 14,
 781     Flag_for_post_loop_opts_igvn     = 1 << 15,
 782     Flag_is_removed_by_peephole      = 1 << 16,
 783     _last_flag                       = Flag_is_removed_by_peephole


 784   };
 785 
 786   class PD;
 787 
 788 private:
 789   juint _class_id;
 790   juint _flags;
 791 
 792   static juint max_flags();
 793 
 794 protected:
 795   // These methods should be called from constructors only.
 796   void init_class_id(juint c) {
 797     _class_id = c; // cast out const
 798   }
 799   void init_flags(uint fl) {
 800     assert(fl <= max_flags(), "invalid node flag");
 801     _flags |= fl;
 802   }
 803   void clear_flag(uint fl) {
 804     assert(fl <= max_flags(), "invalid node flag");
 805     _flags &= ~fl;
 806   }
 807 
 808 public:
 809   const juint class_id() const { return _class_id; }
 810 
 811   const juint flags() const { return _flags; }
 812 
 813   void add_flag(juint fl) { init_flags(fl); }
 814 
 815   void remove_flag(juint fl) { clear_flag(fl); }
 816 
 817   // Return a dense integer opcode number
 818   virtual int Opcode() const;
 819 
 820   // Virtual inherited Node size
 821   virtual uint size_of() const;
 822 
 823   // Other interesting Node properties
 824   #define DEFINE_CLASS_QUERY(type)                           \
 825   bool is_##type() const {                                   \
 826     return ((_class_id & ClassMask_##type) == Class_##type); \
 827   }                                                          \
 828   type##Node *as_##type() const {                            \
 829     assert(is_##type(), "invalid node class: %s", Name()); \
 830     return (type##Node*)this;                                \
 831   }                                                          \
 832   type##Node* isa_##type() const {                           \
 833     return (is_##type()) ? as_##type() : NULL;               \
 834   }
 835 
 836   DEFINE_CLASS_QUERY(AbstractLock)
 837   DEFINE_CLASS_QUERY(Add)
 838   DEFINE_CLASS_QUERY(AddP)
 839   DEFINE_CLASS_QUERY(Allocate)
 840   DEFINE_CLASS_QUERY(AllocateArray)
 841   DEFINE_CLASS_QUERY(ArrayCopy)
 842   DEFINE_CLASS_QUERY(BaseCountedLoop)
 843   DEFINE_CLASS_QUERY(BaseCountedLoopEnd)
 844   DEFINE_CLASS_QUERY(Bool)
 845   DEFINE_CLASS_QUERY(BoxLock)
 846   DEFINE_CLASS_QUERY(Call)
 847   DEFINE_CLASS_QUERY(CallNative)
 848   DEFINE_CLASS_QUERY(CallDynamicJava)
 849   DEFINE_CLASS_QUERY(CallJava)
 850   DEFINE_CLASS_QUERY(CallLeaf)
 851   DEFINE_CLASS_QUERY(CallLeafNoFP)
 852   DEFINE_CLASS_QUERY(CallRuntime)
 853   DEFINE_CLASS_QUERY(CallStaticJava)
 854   DEFINE_CLASS_QUERY(Catch)
 855   DEFINE_CLASS_QUERY(CatchProj)
 856   DEFINE_CLASS_QUERY(CheckCastPP)
 857   DEFINE_CLASS_QUERY(CastII)
 858   DEFINE_CLASS_QUERY(CastLL)
 859   DEFINE_CLASS_QUERY(ConstraintCast)
 860   DEFINE_CLASS_QUERY(ClearArray)
 861   DEFINE_CLASS_QUERY(CMove)
 862   DEFINE_CLASS_QUERY(Cmp)
 863   DEFINE_CLASS_QUERY(CountedLoop)
 864   DEFINE_CLASS_QUERY(CountedLoopEnd)
 865   DEFINE_CLASS_QUERY(DecodeNarrowPtr)
 866   DEFINE_CLASS_QUERY(DecodeN)
 867   DEFINE_CLASS_QUERY(DecodeNKlass)
 868   DEFINE_CLASS_QUERY(EncodeNarrowPtr)
 869   DEFINE_CLASS_QUERY(EncodeP)
 870   DEFINE_CLASS_QUERY(EncodePKlass)
 871   DEFINE_CLASS_QUERY(FastLock)
 872   DEFINE_CLASS_QUERY(FastUnlock)
 873   DEFINE_CLASS_QUERY(Halt)
 874   DEFINE_CLASS_QUERY(If)
 875   DEFINE_CLASS_QUERY(RangeCheck)
 876   DEFINE_CLASS_QUERY(IfProj)
 877   DEFINE_CLASS_QUERY(IfFalse)
 878   DEFINE_CLASS_QUERY(IfTrue)
 879   DEFINE_CLASS_QUERY(Initialize)
 880   DEFINE_CLASS_QUERY(Jump)
 881   DEFINE_CLASS_QUERY(JumpProj)
 882   DEFINE_CLASS_QUERY(LongCountedLoop)
 883   DEFINE_CLASS_QUERY(LongCountedLoopEnd)
 884   DEFINE_CLASS_QUERY(Load)
 885   DEFINE_CLASS_QUERY(LoadStore)
 886   DEFINE_CLASS_QUERY(LoadStoreConditional)
 887   DEFINE_CLASS_QUERY(Lock)
 888   DEFINE_CLASS_QUERY(Loop)
 889   DEFINE_CLASS_QUERY(LShift)
 890   DEFINE_CLASS_QUERY(Mach)
 891   DEFINE_CLASS_QUERY(MachBranch)
 892   DEFINE_CLASS_QUERY(MachCall)
 893   DEFINE_CLASS_QUERY(MachCallNative)
 894   DEFINE_CLASS_QUERY(MachCallDynamicJava)
 895   DEFINE_CLASS_QUERY(MachCallJava)
 896   DEFINE_CLASS_QUERY(MachCallLeaf)
 897   DEFINE_CLASS_QUERY(MachCallRuntime)
 898   DEFINE_CLASS_QUERY(MachCallStaticJava)
 899   DEFINE_CLASS_QUERY(MachConstantBase)
 900   DEFINE_CLASS_QUERY(MachConstant)
 901   DEFINE_CLASS_QUERY(MachGoto)
 902   DEFINE_CLASS_QUERY(MachIf)
 903   DEFINE_CLASS_QUERY(MachJump)
 904   DEFINE_CLASS_QUERY(MachNullCheck)
 905   DEFINE_CLASS_QUERY(MachProj)
 906   DEFINE_CLASS_QUERY(MachReturn)
 907   DEFINE_CLASS_QUERY(MachSafePoint)
 908   DEFINE_CLASS_QUERY(MachSpillCopy)
 909   DEFINE_CLASS_QUERY(MachTemp)
 910   DEFINE_CLASS_QUERY(MachMemBar)
 911   DEFINE_CLASS_QUERY(MachMerge)
 912   DEFINE_CLASS_QUERY(Mem)
 913   DEFINE_CLASS_QUERY(MemBar)
 914   DEFINE_CLASS_QUERY(MemBarStoreStore)
 915   DEFINE_CLASS_QUERY(MergeMem)
 916   DEFINE_CLASS_QUERY(Move)
 917   DEFINE_CLASS_QUERY(Mul)
 918   DEFINE_CLASS_QUERY(Multi)
 919   DEFINE_CLASS_QUERY(MultiBranch)
 920   DEFINE_CLASS_QUERY(Opaque1)
 921   DEFINE_CLASS_QUERY(OuterStripMinedLoop)
 922   DEFINE_CLASS_QUERY(OuterStripMinedLoopEnd)
 923   DEFINE_CLASS_QUERY(Parm)
 924   DEFINE_CLASS_QUERY(PCTable)
 925   DEFINE_CLASS_QUERY(Phi)
 926   DEFINE_CLASS_QUERY(Proj)
 927   DEFINE_CLASS_QUERY(Region)
 928   DEFINE_CLASS_QUERY(Root)
 929   DEFINE_CLASS_QUERY(SafePoint)
 930   DEFINE_CLASS_QUERY(SafePointScalarObject)
 931   DEFINE_CLASS_QUERY(Start)
 932   DEFINE_CLASS_QUERY(Store)
 933   DEFINE_CLASS_QUERY(Sub)
 934   DEFINE_CLASS_QUERY(SubTypeCheck)
 935   DEFINE_CLASS_QUERY(Type)
 936   DEFINE_CLASS_QUERY(Vector)
 937   DEFINE_CLASS_QUERY(VectorMaskCmp)
 938   DEFINE_CLASS_QUERY(VectorUnbox)
 939   DEFINE_CLASS_QUERY(VectorReinterpret);



 940   DEFINE_CLASS_QUERY(LoadVector)
 941   DEFINE_CLASS_QUERY(LoadVectorGather)
 942   DEFINE_CLASS_QUERY(StoreVector)
 943   DEFINE_CLASS_QUERY(StoreVectorScatter)
 944   DEFINE_CLASS_QUERY(ShiftV)
 945   DEFINE_CLASS_QUERY(Unlock)
 946 
 947   #undef DEFINE_CLASS_QUERY
 948 
 949   // duplicate of is_MachSpillCopy()
 950   bool is_SpillCopy () const {
 951     return ((_class_id & ClassMask_MachSpillCopy) == Class_MachSpillCopy);
 952   }
 953 
 954   bool is_Con () const { return (_flags & Flag_is_Con) != 0; }
 955   // The data node which is safe to leave in dead loop during IGVN optimization.
 956   bool is_dead_loop_safe() const;
 957 
 958   // is_Copy() returns copied edge index (0 or 1)
 959   uint is_Copy() const { return (_flags & Flag_is_Copy); }
 960 
 961   virtual bool is_CFG() const { return false; }
 962 
 963   // If this node is control-dependent on a test, can it be
 964   // rerouted to a dominating equivalent test?  This is usually
 965   // true of non-CFG nodes, but can be false for operations which
 966   // depend for their correct sequencing on more than one test.
 967   // (In that case, hoisting to a dominating test may silently
 968   // skip some other important test.)
 969   virtual bool depends_only_on_test() const { assert(!is_CFG(), ""); return true; };
 970 
 971   // When building basic blocks, I need to have a notion of block beginning
 972   // Nodes, next block selector Nodes (block enders), and next block
 973   // projections.  These calls need to work on their machine equivalents.  The
 974   // Ideal beginning Nodes are RootNode, RegionNode and StartNode.
 975   bool is_block_start() const {
 976     if ( is_Region() )
 977       return this == (const Node*)in(0);
 978     else
 979       return is_Start();
 980   }
 981 
 982   // The Ideal control projection Nodes are IfTrue/IfFalse, JumpProjNode, Root,
 983   // Goto and Return.  This call also returns the block ending Node.
 984   virtual const Node *is_block_proj() const;
 985 
 986   // The node is a "macro" node which needs to be expanded before matching
 987   bool is_macro() const { return (_flags & Flag_is_macro) != 0; }
 988   // The node is expensive: the best control is set during loop opts
 989   bool is_expensive() const { return (_flags & Flag_is_expensive) != 0 && in(0) != NULL; }
 990 
 991   // An arithmetic node which accumulates a data in a loop.
 992   // It must have the loop's phi as input and provide a def to the phi.
 993   bool is_reduction() const { return (_flags & Flag_is_reduction) != 0; }
 994 
 995   bool is_predicated_vector() const { return (_flags & Flag_is_predicated_vector) != 0; }
 996 





 997   // Used in lcm to mark nodes that have scheduled
 998   bool is_scheduled() const { return (_flags & Flag_is_scheduled) != 0; }
 999 
1000   bool for_post_loop_opts_igvn() const { return (_flags & Flag_for_post_loop_opts_igvn) != 0; }
1001 
1002 //----------------- Optimization
1003 
1004   // Get the worst-case Type output for this Node.
1005   virtual const class Type *bottom_type() const;
1006 
1007   // If we find a better type for a node, try to record it permanently.
1008   // Return true if this node actually changed.
1009   // Be sure to do the hash_delete game in the "rehash" variant.
1010   void raise_bottom_type(const Type* new_type);
1011 
1012   // Get the address type with which this node uses and/or defs memory,
1013   // or NULL if none.  The address type is conservatively wide.
1014   // Returns non-null for calls, membars, loads, stores, etc.
1015   // Returns TypePtr::BOTTOM if the node touches memory "broadly".
1016   virtual const class TypePtr *adr_type() const { return NULL; }
1017 
1018   // Return an existing node which computes the same function as this node.
1019   // The optimistic combined algorithm requires this to return a Node which
1020   // is a small number of steps away (e.g., one of my inputs).
1021   virtual Node* Identity(PhaseGVN* phase);
1022 
1023   // Return the set of values this Node can take on at runtime.
1024   virtual const Type* Value(PhaseGVN* phase) const;
1025 
1026   // Return a node which is more "ideal" than the current node.
1027   // The invariants on this call are subtle.  If in doubt, read the
1028   // treatise in node.cpp above the default implementation AND TEST WITH
1029   // +VerifyIterativeGVN!
1030   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1031 
1032   // Some nodes have specific Ideal subgraph transformations only if they are
1033   // unique users of specific nodes. Such nodes should be put on IGVN worklist
1034   // for the transformations to happen.
1035   bool has_special_unique_user() const;
1036 
1037   // Skip Proj and CatchProj nodes chains. Check for Null and Top.
1038   Node* find_exact_control(Node* ctrl);
1039 
1040   // Check if 'this' node dominates or equal to 'sub'.
1041   bool dominates(Node* sub, Node_List &nlist);
1042 
1043 protected:
1044   bool remove_dead_region(PhaseGVN *phase, bool can_reshape);
1045 public:
1046 
1047   // See if there is valid pipeline info
1048   static  const Pipeline *pipeline_class();
1049   virtual const Pipeline *pipeline() const;
1050 
1051   // Compute the latency from the def to this instruction of the ith input node
1052   uint latency(uint i);
1053 
1054   // Hash & compare functions, for pessimistic value numbering
1055 
1056   // If the hash function returns the special sentinel value NO_HASH,
1057   // the node is guaranteed never to compare equal to any other node.
1058   // If we accidentally generate a hash with value NO_HASH the node
1059   // won't go into the table and we'll lose a little optimization.
1060   static const uint NO_HASH = 0;
1061   virtual uint hash() const;
1062   virtual bool cmp( const Node &n ) const;
1063 
1064   // Operation appears to be iteratively computed (such as an induction variable)
1065   // It is possible for this operation to return false for a loop-varying
1066   // value, if it appears (by local graph inspection) to be computed by a simple conditional.
1067   bool is_iteratively_computed();
1068 
1069   // Determine if a node is a counted loop induction variable.
1070   // NOTE: The method is defined in "loopnode.cpp".
1071   bool is_cloop_ind_var() const;
1072 
1073   // Return a node with opcode "opc" and same inputs as "this" if one can
1074   // be found; Otherwise return NULL;
1075   Node* find_similar(int opc);
1076 
1077   // Return the unique control out if only one. Null if none or more than one.
1078   Node* unique_ctrl_out_or_null() const;
1079   // Return the unique control out. Asserts if none or more than one control out.
1080   Node* unique_ctrl_out() const;
1081 
1082   // Set control or add control as precedence edge
1083   void ensure_control_or_add_prec(Node* c);
1084 
1085 //----------------- Code Generation
1086 
1087   // Ideal register class for Matching.  Zero means unmatched instruction
1088   // (these are cloned instead of converted to machine nodes).
1089   virtual uint ideal_reg() const;
1090 
1091   static const uint NotAMachineReg;   // must be > max. machine register
1092 
1093   // Do we Match on this edge index or not?  Generally false for Control
1094   // and true for everything else.  Weird for calls & returns.
1095   virtual uint match_edge(uint idx) const;
1096 
1097   // Register class output is returned in
1098   virtual const RegMask &out_RegMask() const;
1099   // Register class input is expected in
1100   virtual const RegMask &in_RegMask(uint) const;
1101   // Should we clone rather than spill this instruction?
1102   bool rematerialize() const;
1103 
1104   // Return JVM State Object if this Node carries debug info, or NULL otherwise
1105   virtual JVMState* jvms() const;
1106 
1107   // Print as assembly
1108   virtual void format( PhaseRegAlloc *, outputStream* st = tty ) const;
1109   // Emit bytes starting at parameter 'ptr'
1110   // Bump 'ptr' by the number of output bytes
1111   virtual void emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const;
1112   // Size of instruction in bytes
1113   virtual uint size(PhaseRegAlloc *ra_) const;
1114 
1115   // Convenience function to extract an integer constant from a node.
1116   // If it is not an integer constant (either Con, CastII, or Mach),
1117   // return value_if_unknown.
1118   jint find_int_con(jint value_if_unknown) const {
1119     const TypeInt* t = find_int_type();
1120     return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown;
1121   }
1122   // Return the constant, knowing it is an integer constant already
1123   jint get_int() const {
1124     const TypeInt* t = find_int_type();
1125     guarantee(t != NULL, "must be con");
1126     return t->get_con();
1127   }
1128   // Here's where the work is done.  Can produce non-constant int types too.
1129   const TypeInt* find_int_type() const;
1130   const TypeInteger* find_integer_type(BasicType bt) const;
1131 
1132   // Same thing for long (and intptr_t, via type.hpp):
1133   jlong get_long() const {
1134     const TypeLong* t = find_long_type();
1135     guarantee(t != NULL, "must be con");
1136     return t->get_con();
1137   }
1138   jlong find_long_con(jint value_if_unknown) const {
1139     const TypeLong* t = find_long_type();
1140     return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown;
1141   }
1142   const TypeLong* find_long_type() const;
1143 
1144   jlong get_integer_as_long(BasicType bt) const {
1145     const TypeInteger* t = find_integer_type(bt);
1146     guarantee(t != NULL && t->is_con(), "must be con");
1147     return t->get_con_as_long(bt);
1148   }
1149   jlong find_integer_as_long(BasicType bt, jlong value_if_unknown) const {
1150     const TypeInteger* t = find_integer_type(bt);
1151     if (t == NULL || !t->is_con())  return value_if_unknown;
1152     return t->get_con_as_long(bt);
1153   }
1154   const TypePtr* get_ptr_type() const;
1155 
1156   // These guys are called by code generated by ADLC:
1157   intptr_t get_ptr() const;
1158   intptr_t get_narrowcon() const;
1159   jdouble getd() const;
1160   jfloat getf() const;
1161 
1162   // Nodes which are pinned into basic blocks
1163   virtual bool pinned() const { return false; }
1164 
1165   // Nodes which use memory without consuming it, hence need antidependences
1166   // More specifically, needs_anti_dependence_check returns true iff the node
1167   // (a) does a load, and (b) does not perform a store (except perhaps to a
1168   // stack slot or some other unaliased location).
1169   bool needs_anti_dependence_check() const;
1170 
1171   // Return which operand this instruction may cisc-spill. In other words,
1172   // return operand position that can convert from reg to memory access
1173   virtual int cisc_operand() const { return AdlcVMDeps::Not_cisc_spillable; }
1174   bool is_cisc_alternate() const { return (_flags & Flag_is_cisc_alternate) != 0; }
1175 
1176   // Whether this is a memory-writing machine node.
1177   bool is_memory_writer() const { return is_Mach() && bottom_type()->has_memory(); }
1178 
1179 //----------------- Printing, etc
1180 #ifndef PRODUCT
1181  private:
1182   int _indent;
1183 
1184  public:
1185   void set_indent(int indent) { _indent = indent; }
1186 
1187  private:
1188   static bool add_to_worklist(Node* n, Node_List* worklist, Arena* old_arena, VectorSet* old_space, VectorSet* new_space);
1189 public:
1190   Node* find(int idx, bool only_ctrl = false); // Search the graph for the given idx.
1191   Node* find_ctrl(int idx); // Search control ancestors for the given idx.
1192   void dump() const { dump("\n"); }  // Print this node.
1193   void dump(const char* suffix, bool mark = false, outputStream *st = tty) const; // Print this node.
1194   void dump(int depth) const;        // Print this node, recursively to depth d
1195   void dump_ctrl(int depth) const;   // Print control nodes, to depth d
1196   void dump_comp() const;            // Print this node in compact representation.
1197   // Print this node in compact representation.
1198   void dump_comp(const char* suffix, outputStream *st = tty) const;
1199   virtual void dump_req(outputStream *st = tty) const;    // Print required-edge info
1200   virtual void dump_prec(outputStream *st = tty) const;   // Print precedence-edge info
1201   virtual void dump_out(outputStream *st = tty) const;    // Print the output edge info
1202   virtual void dump_spec(outputStream *st) const {};      // Print per-node info
1203   // Print compact per-node info
1204   virtual void dump_compact_spec(outputStream *st) const { dump_spec(st); }
1205   void dump_related() const;             // Print related nodes (depends on node at hand).
1206   // Print related nodes up to given depths for input and output nodes.
1207   void dump_related(uint d_in, uint d_out) const;
1208   void dump_related_compact() const;     // Print related nodes in compact representation.
1209   // Collect related nodes.
1210   virtual void related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const;
1211   // Collect nodes starting from this node, explicitly including/excluding control and data links.
1212   void collect_nodes(GrowableArray<Node*> *ns, int d, bool ctrl, bool data) const;
1213 
1214   // Node collectors, to be used in implementations of Node::rel().
1215   // Collect the entire data input graph. Include control inputs if requested.
1216   void collect_nodes_in_all_data(GrowableArray<Node*> *ns, bool ctrl) const;
1217   // Collect the entire control input graph. Include data inputs if requested.
1218   void collect_nodes_in_all_ctrl(GrowableArray<Node*> *ns, bool data) const;
1219   // Collect the entire output graph until hitting and including control nodes.
1220   void collect_nodes_out_all_ctrl_boundary(GrowableArray<Node*> *ns) const;
1221 
1222   void verify_edges(Unique_Node_List &visited); // Verify bi-directional edges
1223   static void verify(int verify_depth, VectorSet& visited, Node_List& worklist);
1224 
1225   // This call defines a class-unique string used to identify class instances
1226   virtual const char *Name() const;
1227 
1228   void dump_format(PhaseRegAlloc *ra) const; // debug access to MachNode::format(...)
1229   // RegMask Print Functions
1230   void dump_in_regmask(int idx) { in_RegMask(idx).dump(); }
1231   void dump_out_regmask() { out_RegMask().dump(); }
1232   static bool in_dump() { return Compile::current()->_in_dump_cnt > 0; }
1233   void fast_dump() const {
1234     tty->print("%4d: %-17s", _idx, Name());
1235     for (uint i = 0; i < len(); i++)
1236       if (in(i))
1237         tty->print(" %4d", in(i)->_idx);
1238       else
1239         tty->print(" NULL");
1240     tty->print("\n");
1241   }
1242 #endif
1243 #ifdef ASSERT
1244   void verify_construction();
1245   bool verify_jvms(const JVMState* jvms) const;
1246 
1247   Node* _debug_orig;                   // Original version of this, if any.
1248   Node*  debug_orig() const            { return _debug_orig; }
1249   void   set_debug_orig(Node* orig);   // _debug_orig = orig
1250   void   dump_orig(outputStream *st, bool print_key = true) const;
1251 
1252   int  _debug_idx;                     // Unique value assigned to every node.
1253   int   debug_idx() const              { return _debug_idx; }
1254   void  set_debug_idx( int debug_idx ) { _debug_idx = debug_idx; }
1255 
1256   int        _hash_lock;               // Barrier to modifications of nodes in the hash table
1257   void  enter_hash_lock() { ++_hash_lock; assert(_hash_lock < 99, "in too many hash tables?"); }
1258   void   exit_hash_lock() { --_hash_lock; assert(_hash_lock >= 0, "mispaired hash locks"); }
1259 
1260   static void init_NodeProperty();
1261 
1262   #if OPTO_DU_ITERATOR_ASSERT
1263   const Node* _last_del;               // The last deleted node.
1264   uint        _del_tick;               // Bumped when a deletion happens..
1265   #endif
1266 #endif
1267 };
1268 
1269 inline bool not_a_node(const Node* n) {
1270   if (n == NULL)                   return true;
1271   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
1272   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
1273   return false;
1274 }
1275 
1276 //-----------------------------------------------------------------------------
1277 // Iterators over DU info, and associated Node functions.
1278 
1279 #if OPTO_DU_ITERATOR_ASSERT
1280 
1281 // Common code for assertion checking on DU iterators.
1282 class DUIterator_Common {
1283 #ifdef ASSERT
1284  protected:
1285   bool         _vdui;               // cached value of VerifyDUIterators
1286   const Node*  _node;               // the node containing the _out array
1287   uint         _outcnt;             // cached node->_outcnt
1288   uint         _del_tick;           // cached node->_del_tick
1289   Node*        _last;               // last value produced by the iterator
1290 
1291   void sample(const Node* node);    // used by c'tor to set up for verifies
1292   void verify(const Node* node, bool at_end_ok = false);
1293   void verify_resync();
1294   void reset(const DUIterator_Common& that);
1295 
1296 // The VDUI_ONLY macro protects code conditionalized on VerifyDUIterators
1297   #define I_VDUI_ONLY(i,x) { if ((i)._vdui) { x; } }
1298 #else
1299   #define I_VDUI_ONLY(i,x) { }
1300 #endif //ASSERT
1301 };
1302 
1303 #define VDUI_ONLY(x)     I_VDUI_ONLY(*this, x)
1304 
1305 // Default DU iterator.  Allows appends onto the out array.
1306 // Allows deletion from the out array only at the current point.
1307 // Usage:
1308 //  for (DUIterator i = x->outs(); x->has_out(i); i++) {
1309 //    Node* y = x->out(i);
1310 //    ...
1311 //  }
1312 // Compiles in product mode to a unsigned integer index, which indexes
1313 // onto a repeatedly reloaded base pointer of x->_out.  The loop predicate
1314 // also reloads x->_outcnt.  If you delete, you must perform "--i" just
1315 // before continuing the loop.  You must delete only the last-produced
1316 // edge.  You must delete only a single copy of the last-produced edge,
1317 // or else you must delete all copies at once (the first time the edge
1318 // is produced by the iterator).
1319 class DUIterator : public DUIterator_Common {
1320   friend class Node;
1321 
1322   // This is the index which provides the product-mode behavior.
1323   // Whatever the product-mode version of the system does to the
1324   // DUI index is done to this index.  All other fields in
1325   // this class are used only for assertion checking.
1326   uint         _idx;
1327 
1328   #ifdef ASSERT
1329   uint         _refresh_tick;    // Records the refresh activity.
1330 
1331   void sample(const Node* node); // Initialize _refresh_tick etc.
1332   void verify(const Node* node, bool at_end_ok = false);
1333   void verify_increment();       // Verify an increment operation.
1334   void verify_resync();          // Verify that we can back up over a deletion.
1335   void verify_finish();          // Verify that the loop terminated properly.
1336   void refresh();                // Resample verification info.
1337   void reset(const DUIterator& that);  // Resample after assignment.
1338   #endif
1339 
1340   DUIterator(const Node* node, int dummy_to_avoid_conversion)
1341     { _idx = 0;                         debug_only(sample(node)); }
1342 
1343  public:
1344   // initialize to garbage; clear _vdui to disable asserts
1345   DUIterator()
1346     { /*initialize to garbage*/         debug_only(_vdui = false); }
1347 
1348   DUIterator(const DUIterator& that)
1349     { _idx = that._idx;                 debug_only(_vdui = false; reset(that)); }
1350 
1351   void operator++(int dummy_to_specify_postfix_op)
1352     { _idx++;                           VDUI_ONLY(verify_increment()); }
1353 
1354   void operator--()
1355     { VDUI_ONLY(verify_resync());       --_idx; }
1356 
1357   ~DUIterator()
1358     { VDUI_ONLY(verify_finish()); }
1359 
1360   void operator=(const DUIterator& that)
1361     { _idx = that._idx;                 debug_only(reset(that)); }
1362 };
1363 
1364 DUIterator Node::outs() const
1365   { return DUIterator(this, 0); }
1366 DUIterator& Node::refresh_out_pos(DUIterator& i) const
1367   { I_VDUI_ONLY(i, i.refresh());        return i; }
1368 bool Node::has_out(DUIterator& i) const
1369   { I_VDUI_ONLY(i, i.verify(this,true));return i._idx < _outcnt; }
1370 Node*    Node::out(DUIterator& i) const
1371   { I_VDUI_ONLY(i, i.verify(this));     return debug_only(i._last=) _out[i._idx]; }
1372 
1373 
1374 // Faster DU iterator.  Disallows insertions into the out array.
1375 // Allows deletion from the out array only at the current point.
1376 // Usage:
1377 //  for (DUIterator_Fast imax, i = x->fast_outs(imax); i < imax; i++) {
1378 //    Node* y = x->fast_out(i);
1379 //    ...
1380 //  }
1381 // Compiles in product mode to raw Node** pointer arithmetic, with
1382 // no reloading of pointers from the original node x.  If you delete,
1383 // you must perform "--i; --imax" just before continuing the loop.
1384 // If you delete multiple copies of the same edge, you must decrement
1385 // imax, but not i, multiple times:  "--i, imax -= num_edges".
1386 class DUIterator_Fast : public DUIterator_Common {
1387   friend class Node;
1388   friend class DUIterator_Last;
1389 
1390   // This is the pointer which provides the product-mode behavior.
1391   // Whatever the product-mode version of the system does to the
1392   // DUI pointer is done to this pointer.  All other fields in
1393   // this class are used only for assertion checking.
1394   Node**       _outp;
1395 
1396   #ifdef ASSERT
1397   void verify(const Node* node, bool at_end_ok = false);
1398   void verify_limit();
1399   void verify_resync();
1400   void verify_relimit(uint n);
1401   void reset(const DUIterator_Fast& that);
1402   #endif
1403 
1404   // Note:  offset must be signed, since -1 is sometimes passed
1405   DUIterator_Fast(const Node* node, ptrdiff_t offset)
1406     { _outp = node->_out + offset;      debug_only(sample(node)); }
1407 
1408  public:
1409   // initialize to garbage; clear _vdui to disable asserts
1410   DUIterator_Fast()
1411     { /*initialize to garbage*/         debug_only(_vdui = false); }
1412 
1413   DUIterator_Fast(const DUIterator_Fast& that)
1414     { _outp = that._outp;               debug_only(_vdui = false; reset(that)); }
1415 
1416   void operator++(int dummy_to_specify_postfix_op)
1417     { _outp++;                          VDUI_ONLY(verify(_node, true)); }
1418 
1419   void operator--()
1420     { VDUI_ONLY(verify_resync());       --_outp; }
1421 
1422   void operator-=(uint n)   // applied to the limit only
1423     { _outp -= n;           VDUI_ONLY(verify_relimit(n));  }
1424 
1425   bool operator<(DUIterator_Fast& limit) {
1426     I_VDUI_ONLY(*this, this->verify(_node, true));
1427     I_VDUI_ONLY(limit, limit.verify_limit());
1428     return _outp < limit._outp;
1429   }
1430 
1431   void operator=(const DUIterator_Fast& that)
1432     { _outp = that._outp;               debug_only(reset(that)); }
1433 };
1434 
1435 DUIterator_Fast Node::fast_outs(DUIterator_Fast& imax) const {
1436   // Assign a limit pointer to the reference argument:
1437   imax = DUIterator_Fast(this, (ptrdiff_t)_outcnt);
1438   // Return the base pointer:
1439   return DUIterator_Fast(this, 0);
1440 }
1441 Node* Node::fast_out(DUIterator_Fast& i) const {
1442   I_VDUI_ONLY(i, i.verify(this));
1443   return debug_only(i._last=) *i._outp;
1444 }
1445 
1446 
1447 // Faster DU iterator.  Requires each successive edge to be removed.
1448 // Does not allow insertion of any edges.
1449 // Usage:
1450 //  for (DUIterator_Last imin, i = x->last_outs(imin); i >= imin; i -= num_edges) {
1451 //    Node* y = x->last_out(i);
1452 //    ...
1453 //  }
1454 // Compiles in product mode to raw Node** pointer arithmetic, with
1455 // no reloading of pointers from the original node x.
1456 class DUIterator_Last : private DUIterator_Fast {
1457   friend class Node;
1458 
1459   #ifdef ASSERT
1460   void verify(const Node* node, bool at_end_ok = false);
1461   void verify_limit();
1462   void verify_step(uint num_edges);
1463   #endif
1464 
1465   // Note:  offset must be signed, since -1 is sometimes passed
1466   DUIterator_Last(const Node* node, ptrdiff_t offset)
1467     : DUIterator_Fast(node, offset) { }
1468 
1469   void operator++(int dummy_to_specify_postfix_op) {} // do not use
1470   void operator<(int)                              {} // do not use
1471 
1472  public:
1473   DUIterator_Last() { }
1474   // initialize to garbage
1475 
1476   DUIterator_Last(const DUIterator_Last& that) = default;
1477 
1478   void operator--()
1479     { _outp--;              VDUI_ONLY(verify_step(1));  }
1480 
1481   void operator-=(uint n)
1482     { _outp -= n;           VDUI_ONLY(verify_step(n));  }
1483 
1484   bool operator>=(DUIterator_Last& limit) {
1485     I_VDUI_ONLY(*this, this->verify(_node, true));
1486     I_VDUI_ONLY(limit, limit.verify_limit());
1487     return _outp >= limit._outp;
1488   }
1489 
1490   DUIterator_Last& operator=(const DUIterator_Last& that) = default;
1491 };
1492 
1493 DUIterator_Last Node::last_outs(DUIterator_Last& imin) const {
1494   // Assign a limit pointer to the reference argument:
1495   imin = DUIterator_Last(this, 0);
1496   // Return the initial pointer:
1497   return DUIterator_Last(this, (ptrdiff_t)_outcnt - 1);
1498 }
1499 Node* Node::last_out(DUIterator_Last& i) const {
1500   I_VDUI_ONLY(i, i.verify(this));
1501   return debug_only(i._last=) *i._outp;
1502 }
1503 
1504 #endif //OPTO_DU_ITERATOR_ASSERT
1505 
1506 #undef I_VDUI_ONLY
1507 #undef VDUI_ONLY
1508 
1509 // An Iterator that truly follows the iterator pattern.  Doesn't
1510 // support deletion but could be made to.
1511 //
1512 //   for (SimpleDUIterator i(n); i.has_next(); i.next()) {
1513 //     Node* m = i.get();
1514 //
1515 class SimpleDUIterator : public StackObj {
1516  private:
1517   Node* node;
1518   DUIterator_Fast i;
1519   DUIterator_Fast imax;
1520  public:
1521   SimpleDUIterator(Node* n): node(n), i(n->fast_outs(imax)) {}
1522   bool has_next() { return i < imax; }
1523   void next() { i++; }
1524   Node* get() { return node->fast_out(i); }
1525 };
1526 
1527 
1528 //-----------------------------------------------------------------------------
1529 // Map dense integer indices to Nodes.  Uses classic doubling-array trick.
1530 // Abstractly provides an infinite array of Node*'s, initialized to NULL.
1531 // Note that the constructor just zeros things, and since I use Arena
1532 // allocation I do not need a destructor to reclaim storage.
1533 class Node_Array : public ResourceObj {
1534   friend class VMStructs;
1535 protected:
1536   Arena* _a;                    // Arena to allocate in
1537   uint   _max;
1538   Node** _nodes;
1539   void   grow( uint i );        // Grow array node to fit
1540 public:
1541   Node_Array(Arena* a, uint max = OptoNodeListSize) : _a(a), _max(max) {
1542     _nodes = NEW_ARENA_ARRAY(a, Node*, max);
1543     clear();
1544   }
1545 
1546   Node_Array(Node_Array* na) : _a(na->_a), _max(na->_max), _nodes(na->_nodes) {}
1547   Node *operator[] ( uint i ) const // Lookup, or NULL for not mapped
1548   { return (i<_max) ? _nodes[i] : (Node*)NULL; }
1549   Node* at(uint i) const { assert(i<_max,"oob"); return _nodes[i]; }
1550   Node** adr() { return _nodes; }
1551   // Extend the mapping: index i maps to Node *n.
1552   void map( uint i, Node *n ) { if( i>=_max ) grow(i); _nodes[i] = n; }
1553   void insert( uint i, Node *n );
1554   void remove( uint i );        // Remove, preserving order
1555   // Clear all entries in _nodes to NULL but keep storage
1556   void clear() {
1557     Copy::zero_to_bytes(_nodes, _max * sizeof(Node*));
1558   }
1559 
1560   uint Size() const { return _max; }
1561   void dump() const;
1562 };
1563 
1564 class Node_List : public Node_Array {
1565   friend class VMStructs;
1566   uint _cnt;
1567 public:
1568   Node_List(uint max = OptoNodeListSize) : Node_Array(Thread::current()->resource_area(), max), _cnt(0) {}
1569   Node_List(Arena *a, uint max = OptoNodeListSize) : Node_Array(a, max), _cnt(0) {}
1570   bool contains(const Node* n) const {
1571     for (uint e = 0; e < size(); e++) {
1572       if (at(e) == n) return true;
1573     }
1574     return false;
1575   }
1576   void insert( uint i, Node *n ) { Node_Array::insert(i,n); _cnt++; }
1577   void remove( uint i ) { Node_Array::remove(i); _cnt--; }
1578   void push( Node *b ) { map(_cnt++,b); }
1579   void yank( Node *n );         // Find and remove
1580   Node *pop() { return _nodes[--_cnt]; }
1581   void clear() { _cnt = 0; Node_Array::clear(); } // retain storage
1582   void copy(const Node_List& from) {
1583     if (from._max > _max) {
1584       grow(from._max);
1585     }
1586     _cnt = from._cnt;
1587     Copy::conjoint_words_to_higher((HeapWord*)&from._nodes[0], (HeapWord*)&_nodes[0], from._max * sizeof(Node*));
1588   }
1589 
1590   uint size() const { return _cnt; }
1591   void dump() const;
1592   void dump_simple() const;
1593 };
1594 
1595 //------------------------------Unique_Node_List-------------------------------
1596 class Unique_Node_List : public Node_List {
1597   friend class VMStructs;
1598   VectorSet _in_worklist;
1599   uint _clock_index;            // Index in list where to pop from next
1600 public:
1601   Unique_Node_List() : Node_List(), _clock_index(0) {}
1602   Unique_Node_List(Arena *a) : Node_List(a), _in_worklist(a), _clock_index(0) {}
1603 
1604   void remove( Node *n );
1605   bool member( Node *n ) { return _in_worklist.test(n->_idx) != 0; }
1606   VectorSet& member_set(){ return _in_worklist; }
1607 
1608   void push(Node* b) {
1609     if( !_in_worklist.test_set(b->_idx) )
1610       Node_List::push(b);
1611   }
1612   Node *pop() {
1613     if( _clock_index >= size() ) _clock_index = 0;
1614     Node *b = at(_clock_index);
1615     map( _clock_index, Node_List::pop());
1616     if (size() != 0) _clock_index++; // Always start from 0
1617     _in_worklist.remove(b->_idx);
1618     return b;
1619   }
1620   Node *remove(uint i) {
1621     Node *b = Node_List::at(i);
1622     _in_worklist.remove(b->_idx);
1623     map(i,Node_List::pop());
1624     return b;
1625   }
1626   void yank(Node *n) {
1627     _in_worklist.remove(n->_idx);
1628     Node_List::yank(n);
1629   }
1630   void  clear() {
1631     _in_worklist.clear();        // Discards storage but grows automatically
1632     Node_List::clear();
1633     _clock_index = 0;
1634   }
1635 
1636   // Used after parsing to remove useless nodes before Iterative GVN
1637   void remove_useless_nodes(VectorSet& useful);
1638 
1639   bool contains(const Node* n) const {
1640     fatal("use faster member() instead");
1641     return false;
1642   }
1643 
1644 #ifndef PRODUCT
1645   void print_set() const { _in_worklist.print(); }
1646 #endif
1647 };
1648 
1649 // Inline definition of Compile::record_for_igvn must be deferred to this point.
1650 inline void Compile::record_for_igvn(Node* n) {
1651   _for_igvn->push(n);
1652 }
1653 
1654 //------------------------------Node_Stack-------------------------------------
1655 class Node_Stack {
1656   friend class VMStructs;
1657 protected:
1658   struct INode {
1659     Node *node; // Processed node
1660     uint  indx; // Index of next node's child
1661   };
1662   INode *_inode_top; // tos, stack grows up
1663   INode *_inode_max; // End of _inodes == _inodes + _max
1664   INode *_inodes;    // Array storage for the stack
1665   Arena *_a;         // Arena to allocate in
1666   void grow();
1667 public:
1668   Node_Stack(int size) {
1669     size_t max = (size > OptoNodeListSize) ? size : OptoNodeListSize;
1670     _a = Thread::current()->resource_area();
1671     _inodes = NEW_ARENA_ARRAY( _a, INode, max );
1672     _inode_max = _inodes + max;
1673     _inode_top = _inodes - 1; // stack is empty
1674   }
1675 
1676   Node_Stack(Arena *a, int size) : _a(a) {
1677     size_t max = (size > OptoNodeListSize) ? size : OptoNodeListSize;
1678     _inodes = NEW_ARENA_ARRAY( _a, INode, max );
1679     _inode_max = _inodes + max;
1680     _inode_top = _inodes - 1; // stack is empty
1681   }
1682 
1683   void pop() {
1684     assert(_inode_top >= _inodes, "node stack underflow");
1685     --_inode_top;
1686   }
1687   void push(Node *n, uint i) {
1688     ++_inode_top;
1689     if (_inode_top >= _inode_max) grow();
1690     INode *top = _inode_top; // optimization
1691     top->node = n;
1692     top->indx = i;
1693   }
1694   Node *node() const {
1695     return _inode_top->node;
1696   }
1697   Node* node_at(uint i) const {
1698     assert(_inodes + i <= _inode_top, "in range");
1699     return _inodes[i].node;
1700   }
1701   uint index() const {
1702     return _inode_top->indx;
1703   }
1704   uint index_at(uint i) const {
1705     assert(_inodes + i <= _inode_top, "in range");
1706     return _inodes[i].indx;
1707   }
1708   void set_node(Node *n) {
1709     _inode_top->node = n;
1710   }
1711   void set_index(uint i) {
1712     _inode_top->indx = i;
1713   }
1714   uint size_max() const { return (uint)pointer_delta(_inode_max, _inodes,  sizeof(INode)); } // Max size
1715   uint size() const { return (uint)pointer_delta((_inode_top+1), _inodes,  sizeof(INode)); } // Current size
1716   bool is_nonempty() const { return (_inode_top >= _inodes); }
1717   bool is_empty() const { return (_inode_top < _inodes); }
1718   void clear() { _inode_top = _inodes - 1; } // retain storage
1719 
1720   // Node_Stack is used to map nodes.
1721   Node* find(uint idx) const;
1722 };
1723 
1724 
1725 //-----------------------------Node_Notes--------------------------------------
1726 // Debugging or profiling annotations loosely and sparsely associated
1727 // with some nodes.  See Compile::node_notes_at for the accessor.
1728 class Node_Notes {
1729   friend class VMStructs;
1730   JVMState* _jvms;
1731 
1732 public:
1733   Node_Notes(JVMState* jvms = NULL) {
1734     _jvms = jvms;
1735   }
1736 
1737   JVMState* jvms()            { return _jvms; }
1738   void  set_jvms(JVMState* x) {        _jvms = x; }
1739 
1740   // True if there is nothing here.
1741   bool is_clear() {
1742     return (_jvms == NULL);
1743   }
1744 
1745   // Make there be nothing here.
1746   void clear() {
1747     _jvms = NULL;
1748   }
1749 
1750   // Make a new, clean node notes.
1751   static Node_Notes* make(Compile* C) {
1752     Node_Notes* nn = NEW_ARENA_ARRAY(C->comp_arena(), Node_Notes, 1);
1753     nn->clear();
1754     return nn;
1755   }
1756 
1757   Node_Notes* clone(Compile* C) {
1758     Node_Notes* nn = NEW_ARENA_ARRAY(C->comp_arena(), Node_Notes, 1);
1759     (*nn) = (*this);
1760     return nn;
1761   }
1762 
1763   // Absorb any information from source.
1764   bool update_from(Node_Notes* source) {
1765     bool changed = false;
1766     if (source != NULL) {
1767       if (source->jvms() != NULL) {
1768         set_jvms(source->jvms());
1769         changed = true;
1770       }
1771     }
1772     return changed;
1773   }
1774 };
1775 
1776 // Inlined accessors for Compile::node_nodes that require the preceding class:
1777 inline Node_Notes*
1778 Compile::locate_node_notes(GrowableArray<Node_Notes*>* arr,
1779                            int idx, bool can_grow) {
1780   assert(idx >= 0, "oob");
1781   int block_idx = (idx >> _log2_node_notes_block_size);
1782   int grow_by = (block_idx - (arr == NULL? 0: arr->length()));
1783   if (grow_by >= 0) {
1784     if (!can_grow) return NULL;
1785     grow_node_notes(arr, grow_by + 1);
1786   }
1787   if (arr == NULL) return NULL;
1788   // (Every element of arr is a sub-array of length _node_notes_block_size.)
1789   return arr->at(block_idx) + (idx & (_node_notes_block_size-1));
1790 }
1791 
1792 inline bool
1793 Compile::set_node_notes_at(int idx, Node_Notes* value) {
1794   if (value == NULL || value->is_clear())
1795     return false;  // nothing to write => write nothing
1796   Node_Notes* loc = locate_node_notes(_node_note_array, idx, true);
1797   assert(loc != NULL, "");
1798   return loc->update_from(value);
1799 }
1800 
1801 
1802 //------------------------------TypeNode---------------------------------------
1803 // Node with a Type constant.
1804 class TypeNode : public Node {
1805 protected:
1806   virtual uint hash() const;    // Check the type
1807   virtual bool cmp( const Node &n ) const;
1808   virtual uint size_of() const; // Size is bigger
1809   const Type* const _type;
1810 public:
1811   void set_type(const Type* t) {
1812     assert(t != NULL, "sanity");
1813     debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
1814     *(const Type**)&_type = t;   // cast away const-ness
1815     // If this node is in the hash table, make sure it doesn't need a rehash.
1816     assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
1817   }
1818   const Type* type() const { assert(_type != NULL, "sanity"); return _type; };
1819   TypeNode( const Type *t, uint required ) : Node(required), _type(t) {
1820     init_class_id(Class_Type);
1821   }
1822   virtual const Type* Value(PhaseGVN* phase) const;
1823   virtual const Type *bottom_type() const;
1824   virtual       uint  ideal_reg() const;
1825 #ifndef PRODUCT
1826   virtual void dump_spec(outputStream *st) const;
1827   virtual void dump_compact_spec(outputStream *st) const;
1828 #endif
1829 };
1830 
1831 #include "opto/opcodes.hpp"
1832 
1833 #define Op_IL(op) \
1834   inline int Op_ ## op(BasicType bt) { \
1835   assert(bt == T_INT || bt == T_LONG, "only for int or longs"); \
1836   if (bt == T_INT) { \
1837     return Op_## op ## I; \
1838   } \
1839   return Op_## op ## L; \
1840 }
1841 
1842 Op_IL(Add)
1843 Op_IL(Sub)
1844 Op_IL(Mul)
1845 Op_IL(URShift)
1846 Op_IL(LShift)
1847 Op_IL(Xor)
1848 Op_IL(Cmp)
1849 
1850 inline int Op_ConIL(BasicType bt) {
1851   assert(bt == T_INT || bt == T_LONG, "only for int or longs");
1852   if (bt == T_INT) {
1853     return Op_ConI;
1854   }
1855   return Op_ConL;
1856 }
1857 
1858 inline int Op_Cmp_unsigned(BasicType bt) {
1859   assert(bt == T_INT || bt == T_LONG, "only for int or longs");
1860   if (bt == T_INT) {
1861     return Op_CmpU;
1862   }
1863   return Op_CmpUL;
1864 }
1865 
1866 inline int Op_Cast(BasicType bt) {
1867   assert(bt == T_INT || bt == T_LONG, "only for int or longs");
1868   if (bt == T_INT) {
1869     return Op_CastII;
1870   }
1871   return Op_CastLL;
1872 }
1873 
1874 #endif // SHARE_OPTO_NODE_HPP
--- EOF ---