1 /*
   2  * Copyright (c) 1997, 2016, 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_VM_OPTO_NODE_HPP
  26 #define SHARE_VM_OPTO_NODE_HPP
  27 
  28 #include "libadt/port.hpp"
  29 #include "libadt/vectset.hpp"
  30 #include "opto/compile.hpp"
  31 #include "opto/type.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 Block;
  45 class BoolNode;
  46 class BoxLockNode;
  47 class CMoveNode;
  48 class CallDynamicJavaNode;
  49 class CallJavaNode;
  50 class CallLeafNode;
  51 class CallNode;
  52 class CallRuntimeNode;
  53 class CallStaticJavaNode;
  54 class CatchNode;
  55 class CatchProjNode;
  56 class CheckCastPPNode;
  57 class CastIINode;
  58 class ClearArrayNode;
  59 class CmpNode;
  60 class CodeBuffer;
  61 class ConstraintCastNode;
  62 class ConNode;
  63 class CountedLoopNode;
  64 class CountedLoopEndNode;
  65 class DecodeNarrowPtrNode;
  66 class DecodeNNode;
  67 class DecodeNKlassNode;
  68 class EncodeNarrowPtrNode;
  69 class EncodePNode;
  70 class EncodePKlassNode;
  71 class FastLockNode;
  72 class FastUnlockNode;
  73 class IfNode;
  74 class IfProjNode;
  75 class IfFalseNode;
  76 class IfTrueNode;
  77 class InitializeNode;
  78 class JVMState;
  79 class JumpNode;
  80 class JumpProjNode;
  81 class LoadNode;
  82 class LoadStoreNode;
  83 class LockNode;
  84 class LoopNode;
  85 class MachBranchNode;
  86 class MachCallDynamicJavaNode;
  87 class MachCallJavaNode;
  88 class MachCallLeafNode;
  89 class MachCallNode;
  90 class MachCallRuntimeNode;
  91 class MachCallStaticJavaNode;
  92 class MachConstantBaseNode;
  93 class MachConstantNode;
  94 class MachGotoNode;
  95 class MachIfNode;
  96 class MachNode;
  97 class MachNullCheckNode;
  98 class MachProjNode;
  99 class MachReturnNode;
 100 class MachSafePointNode;
 101 class MachSpillCopyNode;
 102 class MachTempNode;
 103 class MachMergeNode;
 104 class MachMemBarNode;
 105 class Matcher;
 106 class MemBarNode;
 107 class MemBarStoreStoreNode;
 108 class MemNode;
 109 class MergeMemNode;
 110 class MulNode;
 111 class MultiNode;
 112 class MultiBranchNode;
 113 class NeverBranchNode;
 114 class Node;
 115 class Node_Array;
 116 class Node_List;
 117 class Node_Stack;
 118 class NullCheckNode;
 119 class OopMap;
 120 class ParmNode;
 121 class PCTableNode;
 122 class PhaseCCP;
 123 class PhaseGVN;
 124 class PhaseIterGVN;
 125 class PhaseRegAlloc;
 126 class PhaseTransform;
 127 class PhaseValues;
 128 class PhiNode;
 129 class Pipeline;
 130 class ProjNode;
 131 class RegMask;
 132 class RegionNode;
 133 class RootNode;
 134 class SafePointNode;
 135 class SafePointScalarObjectNode;
 136 class ShenandoahBarrierNode;
 137 class StartNode;
 138 class State;
 139 class StoreNode;
 140 class SubNode;
 141 class Type;
 142 class TypeNode;
 143 class UnlockNode;
 144 class VectorNode;
 145 class LoadVectorNode;
 146 class StoreVectorNode;
 147 class VectorSet;
 148 typedef void (*NFunc)(Node&,void*);
 149 extern "C" {
 150   typedef int (*C_sort_func_t)(const void *, const void *);
 151 }
 152 
 153 // The type of all node counts and indexes.
 154 // It must hold at least 16 bits, but must also be fast to load and store.
 155 // This type, if less than 32 bits, could limit the number of possible nodes.
 156 // (To make this type platform-specific, move to globalDefinitions_xxx.hpp.)
 157 typedef unsigned int node_idx_t;
 158 
 159 
 160 #ifndef OPTO_DU_ITERATOR_ASSERT
 161 #ifdef ASSERT
 162 #define OPTO_DU_ITERATOR_ASSERT 1
 163 #else
 164 #define OPTO_DU_ITERATOR_ASSERT 0
 165 #endif
 166 #endif //OPTO_DU_ITERATOR_ASSERT
 167 
 168 #if OPTO_DU_ITERATOR_ASSERT
 169 class DUIterator;
 170 class DUIterator_Fast;
 171 class DUIterator_Last;
 172 #else
 173 typedef uint   DUIterator;
 174 typedef Node** DUIterator_Fast;
 175 typedef Node** DUIterator_Last;
 176 #endif
 177 
 178 // Node Sentinel
 179 #define NodeSentinel (Node*)-1
 180 
 181 // Unknown count frequency
 182 #define COUNT_UNKNOWN (-1.0f)
 183 
 184 //------------------------------Node-------------------------------------------
 185 // Nodes define actions in the program.  They create values, which have types.
 186 // They are both vertices in a directed graph and program primitives.  Nodes
 187 // are labeled; the label is the "opcode", the primitive function in the lambda
 188 // calculus sense that gives meaning to the Node.  Node inputs are ordered (so
 189 // that "a-b" is different from "b-a").  The inputs to a Node are the inputs to
 190 // the Node's function.  These inputs also define a Type equation for the Node.
 191 // Solving these Type equations amounts to doing dataflow analysis.
 192 // Control and data are uniformly represented in the graph.  Finally, Nodes
 193 // have a unique dense integer index which is used to index into side arrays
 194 // whenever I have phase-specific information.
 195 
 196 class Node {
 197   friend class VMStructs;
 198 
 199   // Lots of restrictions on cloning Nodes
 200   Node(const Node&);            // not defined; linker error to use these
 201   Node &operator=(const Node &rhs);
 202 
 203 public:
 204   friend class Compile;
 205   #if OPTO_DU_ITERATOR_ASSERT
 206   friend class DUIterator_Common;
 207   friend class DUIterator;
 208   friend class DUIterator_Fast;
 209   friend class DUIterator_Last;
 210   #endif
 211 
 212   // Because Nodes come and go, I define an Arena of Node structures to pull
 213   // from.  This should allow fast access to node creation & deletion.  This
 214   // field is a local cache of a value defined in some "program fragment" for
 215   // which these Nodes are just a part of.
 216 
 217   // New Operator that takes a Compile pointer, this will eventually
 218   // be the "new" New operator.
 219   inline void* operator new( size_t x, Compile* C) throw() {
 220     Node* n = (Node*)C->node_arena()->Amalloc_D(x);
 221 #ifdef ASSERT
 222     n->_in = (Node**)n; // magic cookie for assertion check
 223 #endif
 224     n->_out = (Node**)C;
 225     return (void*)n;
 226   }
 227 
 228   // Delete is a NOP
 229   void operator delete( void *ptr ) {}
 230   // Fancy destructor; eagerly attempt to reclaim Node numberings and storage
 231   void destruct();
 232 
 233   // Create a new Node.  Required is the number is of inputs required for
 234   // semantic correctness.
 235   Node( uint required );
 236 
 237   // Create a new Node with given input edges.
 238   // This version requires use of the "edge-count" new.
 239   // E.g.  new (C,3) FooNode( C, NULL, left, right );
 240   Node( Node *n0 );
 241   Node( Node *n0, Node *n1 );
 242   Node( Node *n0, Node *n1, Node *n2 );
 243   Node( Node *n0, Node *n1, Node *n2, Node *n3 );
 244   Node( Node *n0, Node *n1, Node *n2, Node *n3, Node *n4 );
 245   Node( Node *n0, Node *n1, Node *n2, Node *n3, Node *n4, Node *n5 );
 246   Node( Node *n0, Node *n1, Node *n2, Node *n3,
 247             Node *n4, Node *n5, Node *n6 );
 248 
 249   // Clone an inherited Node given only the base Node type.
 250   Node* clone() const;
 251 
 252   // Clone a Node, immediately supplying one or two new edges.
 253   // The first and second arguments, if non-null, replace in(1) and in(2),
 254   // respectively.
 255   Node* clone_with_data_edge(Node* in1, Node* in2 = NULL) const {
 256     Node* nn = clone();
 257     if (in1 != NULL)  nn->set_req(1, in1);
 258     if (in2 != NULL)  nn->set_req(2, in2);
 259     return nn;
 260   }
 261 
 262 private:
 263   // Shared setup for the above constructors.
 264   // Handles all interactions with Compile::current.
 265   // Puts initial values in all Node fields except _idx.
 266   // Returns the initial value for _idx, which cannot
 267   // be initialized by assignment.
 268   inline int Init(int req, Compile* C);
 269 
 270 //----------------- input edge handling
 271 protected:
 272   friend class PhaseCFG;        // Access to address of _in array elements
 273   Node **_in;                   // Array of use-def references to Nodes
 274   Node **_out;                  // Array of def-use references to Nodes
 275 
 276   // Input edges are split into two categories.  Required edges are required
 277   // for semantic correctness; order is important and NULLs are allowed.
 278   // Precedence edges are used to help determine execution order and are
 279   // added, e.g., for scheduling purposes.  They are unordered and not
 280   // duplicated; they have no embedded NULLs.  Edges from 0 to _cnt-1
 281   // are required, from _cnt to _max-1 are precedence edges.
 282   node_idx_t _cnt;              // Total number of required Node inputs.
 283 
 284   node_idx_t _max;              // Actual length of input array.
 285 
 286   // Output edges are an unordered list of def-use edges which exactly
 287   // correspond to required input edges which point from other nodes
 288   // to this one.  Thus the count of the output edges is the number of
 289   // users of this node.
 290   node_idx_t _outcnt;           // Total number of Node outputs.
 291 
 292   node_idx_t _outmax;           // Actual length of output array.
 293 
 294   // Grow the actual input array to the next larger power-of-2 bigger than len.
 295   void grow( uint len );
 296   // Grow the output array to the next larger power-of-2 bigger than len.
 297   void out_grow( uint len );
 298 
 299  public:
 300   // Each Node is assigned a unique small/dense number.  This number is used
 301   // to index into auxiliary arrays of data and bit vectors.
 302   // The field _idx is declared constant to defend against inadvertent assignments,
 303   // since it is used by clients as a naked field. However, the field's value can be
 304   // changed using the set_idx() method.
 305   //
 306   // The PhaseRenumberLive phase renumbers nodes based on liveness information.
 307   // Therefore, it updates the value of the _idx field. The parse-time _idx is
 308   // preserved in _parse_idx.
 309   const node_idx_t _idx;
 310   DEBUG_ONLY(const node_idx_t _parse_idx;)
 311 
 312   // Get the (read-only) number of input edges
 313   uint req() const { return _cnt; }
 314   uint len() const { return _max; }
 315   // Get the (read-only) number of output edges
 316   uint outcnt() const { return _outcnt; }
 317 
 318 #if OPTO_DU_ITERATOR_ASSERT
 319   // Iterate over the out-edges of this node.  Deletions are illegal.
 320   inline DUIterator outs() const;
 321   // Use this when the out array might have changed to suppress asserts.
 322   inline DUIterator& refresh_out_pos(DUIterator& i) const;
 323   // Does the node have an out at this position?  (Used for iteration.)
 324   inline bool has_out(DUIterator& i) const;
 325   inline Node*    out(DUIterator& i) const;
 326   // Iterate over the out-edges of this node.  All changes are illegal.
 327   inline DUIterator_Fast fast_outs(DUIterator_Fast& max) const;
 328   inline Node*    fast_out(DUIterator_Fast& i) const;
 329   // Iterate over the out-edges of this node, deleting one at a time.
 330   inline DUIterator_Last last_outs(DUIterator_Last& min) const;
 331   inline Node*    last_out(DUIterator_Last& i) const;
 332   // The inline bodies of all these methods are after the iterator definitions.
 333 #else
 334   // Iterate over the out-edges of this node.  Deletions are illegal.
 335   // This iteration uses integral indexes, to decouple from array reallocations.
 336   DUIterator outs() const  { return 0; }
 337   // Use this when the out array might have changed to suppress asserts.
 338   DUIterator refresh_out_pos(DUIterator i) const { return i; }
 339 
 340   // Reference to the i'th output Node.  Error if out of bounds.
 341   Node*    out(DUIterator i) const { assert(i < _outcnt, "oob"); return _out[i]; }
 342   // Does the node have an out at this position?  (Used for iteration.)
 343   bool has_out(DUIterator i) const { return i < _outcnt; }
 344 
 345   // Iterate over the out-edges of this node.  All changes are illegal.
 346   // This iteration uses a pointer internal to the out array.
 347   DUIterator_Fast fast_outs(DUIterator_Fast& max) const {
 348     Node** out = _out;
 349     // Assign a limit pointer to the reference argument:
 350     max = out + (ptrdiff_t)_outcnt;
 351     // Return the base pointer:
 352     return out;
 353   }
 354   Node*    fast_out(DUIterator_Fast i) const  { return *i; }
 355   // Iterate over the out-edges of this node, deleting one at a time.
 356   // This iteration uses a pointer internal to the out array.
 357   DUIterator_Last last_outs(DUIterator_Last& min) const {
 358     Node** out = _out;
 359     // Assign a limit pointer to the reference argument:
 360     min = out;
 361     // Return the pointer to the start of the iteration:
 362     return out + (ptrdiff_t)_outcnt - 1;
 363   }
 364   Node*    last_out(DUIterator_Last i) const  { return *i; }
 365 #endif
 366 
 367   // Reference to the i'th input Node.  Error if out of bounds.
 368   Node* in(uint i) const { assert(i < _max, err_msg_res("oob: i=%d, _max=%d", i, _max)); return _in[i]; }
 369   // Reference to the i'th input Node.  NULL if out of bounds.
 370   Node* lookup(uint i) const { return ((i < _max) ? _in[i] : NULL); }
 371   // Reference to the i'th output Node.  Error if out of bounds.
 372   // Use this accessor sparingly.  We are going trying to use iterators instead.
 373   Node* raw_out(uint i) const { assert(i < _outcnt,"oob"); return _out[i]; }
 374   // Return the unique out edge.
 375   Node* unique_out() const { assert(_outcnt==1,"not unique"); return _out[0]; }
 376   // Delete out edge at position 'i' by moving last out edge to position 'i'
 377   void  raw_del_out(uint i) {
 378     assert(i < _outcnt,"oob");
 379     assert(_outcnt > 0,"oob");
 380     #if OPTO_DU_ITERATOR_ASSERT
 381     // Record that a change happened here.
 382     debug_only(_last_del = _out[i]; ++_del_tick);
 383     #endif
 384     _out[i] = _out[--_outcnt];
 385     // Smash the old edge so it can't be used accidentally.
 386     debug_only(_out[_outcnt] = (Node *)(uintptr_t)0xdeadbeef);
 387   }
 388 
 389 #ifdef ASSERT
 390   bool is_dead() const;
 391 #define is_not_dead(n) ((n) == NULL || !VerifyIterativeGVN || !((n)->is_dead()))
 392 #endif
 393   // Check whether node has become unreachable
 394   bool is_unreachable(PhaseIterGVN &igvn) const;
 395 
 396   // Set a required input edge, also updates corresponding output edge
 397   void add_req( Node *n ); // Append a NEW required input
 398   void add_req( Node *n0, Node *n1 ) {
 399     add_req(n0); add_req(n1); }
 400   void add_req( Node *n0, Node *n1, Node *n2 ) {
 401     add_req(n0); add_req(n1); add_req(n2); }
 402   void add_req_batch( Node* n, uint m ); // Append m NEW required inputs (all n).
 403   void del_req( uint idx ); // Delete required edge & compact
 404   void del_req_ordered( uint idx ); // Delete required edge & compact with preserved order
 405   void ins_req( uint i, Node *n ); // Insert a NEW required input
 406   void set_req( uint i, Node *n ) {
 407     assert( is_not_dead(n), "can not use dead node");
 408     assert( i < _cnt, err_msg_res("oob: i=%d, _cnt=%d", i, _cnt));
 409     assert( !VerifyHashTableKeys || _hash_lock == 0,
 410             "remove node from hash table before modifying it");
 411     Node** p = &_in[i];    // cache this._in, across the del_out call
 412     if (*p != NULL)  (*p)->del_out((Node *)this);
 413     (*p) = n;
 414     if (n != NULL)      n->add_out((Node *)this);
 415   }
 416   // Light version of set_req() to init inputs after node creation.
 417   void init_req( uint i, Node *n ) {
 418     assert( i == 0 && this == n ||
 419             is_not_dead(n), "can not use dead node");
 420     assert( i < _cnt, "oob");
 421     assert( !VerifyHashTableKeys || _hash_lock == 0,
 422             "remove node from hash table before modifying it");
 423     assert( _in[i] == NULL, "sanity");
 424     _in[i] = n;
 425     if (n != NULL)      n->add_out((Node *)this);
 426   }
 427   // Find first occurrence of n among my edges:
 428   int find_edge(Node* n);
 429   int find_prec_edge(Node* n) {
 430     for (uint i = req(); i < len(); i++) {
 431       if (_in[i] == n) return i;
 432       if (_in[i] == NULL) {
 433         DEBUG_ONLY( while ((++i) < len()) assert(_in[i] == NULL, "Gap in prec edges!"); )
 434         break;
 435       }
 436     }
 437     return -1;
 438   }
 439   int replace_edge(Node* old, Node* neww);
 440   int replace_edges_in_range(Node* old, Node* neww, int start, int end);
 441   // NULL out all inputs to eliminate incoming Def-Use edges.
 442   // Return the number of edges between 'n' and 'this'
 443   int  disconnect_inputs(Node *n, Compile *c);
 444 
 445   // Quickly, return true if and only if I am Compile::current()->top().
 446   bool is_top() const {
 447     assert((this == (Node*) Compile::current()->top()) == (_out == NULL), "");
 448     return (_out == NULL);
 449   }
 450   // Reaffirm invariants for is_top.  (Only from Compile::set_cached_top_node.)
 451   void setup_is_top();
 452 
 453   // Strip away casting.  (It is depth-limited.)
 454   Node* uncast() const;
 455   // Return whether two Nodes are equivalent, after stripping casting.
 456   bool eqv_uncast(const Node* n) const {
 457     return (this->uncast() == n->uncast());
 458   }
 459   // Return true if the current node has an out that matches opcode.
 460   bool has_out_with(int opcode);
 461 
 462   // Find out of current node that matches opcode.
 463   Node* find_out_with(int opcode);
 464 
 465 private:
 466   static Node* uncast_helper(const Node* n);
 467 
 468   // Add an output edge to the end of the list
 469   void add_out( Node *n ) {
 470     if (is_top())  return;
 471     if( _outcnt == _outmax ) out_grow(_outcnt);
 472     _out[_outcnt++] = n;
 473   }
 474   // Delete an output edge
 475   void del_out( Node *n ) {
 476     if (is_top())  return;
 477     Node** outp = &_out[_outcnt];
 478     // Find and remove n
 479     do {
 480       assert(outp > _out, "Missing Def-Use edge");
 481     } while (*--outp != n);
 482     *outp = _out[--_outcnt];
 483     // Smash the old edge so it can't be used accidentally.
 484     debug_only(_out[_outcnt] = (Node *)(uintptr_t)0xdeadbeef);
 485     // Record that a change happened here.
 486     #if OPTO_DU_ITERATOR_ASSERT
 487     debug_only(_last_del = n; ++_del_tick);
 488     #endif
 489   }
 490   // Close gap after removing edge.
 491   void close_prec_gap_at(uint gap) {
 492     assert(_cnt <= gap && gap < _max, "no valid prec edge");
 493     uint i = gap;
 494     Node *last = NULL;
 495     for (; i < _max-1; ++i) {
 496       Node *next = _in[i+1];
 497       if (next == NULL) break;
 498       last = next;
 499     }
 500     _in[gap] = last; // Move last slot to empty one.
 501     _in[i] = NULL;   // NULL out last slot.
 502   }
 503 
 504 public:
 505   // Globally replace this node by a given new node, updating all uses.
 506   void replace_by(Node* new_node);
 507   // Globally replace this node by a given new node, updating all uses
 508   // and cutting input edges of old node.
 509   void subsume_by(Node* new_node, Compile* c) {
 510     replace_by(new_node);
 511     disconnect_inputs(NULL, c);
 512   }
 513   void set_req_X( uint i, Node *n, PhaseIterGVN *igvn );
 514   // Find the one non-null required input.  RegionNode only
 515   Node *nonnull_req() const;
 516   // Add or remove precedence edges
 517   void add_prec( Node *n );
 518   void rm_prec( uint i );
 519 
 520   // Note: prec(i) will not necessarily point to n if edge already exists.
 521   void set_prec( uint i, Node *n ) {
 522     assert(i < _max, err_msg("oob: i=%d, _max=%d", i, _max));
 523     assert(is_not_dead(n), "can not use dead node");
 524     assert(i >= _cnt, "not a precedence edge");
 525     // Avoid spec violation: duplicated prec edge.
 526     if (_in[i] == n) return;
 527     if (n == NULL || find_prec_edge(n) != -1) {
 528       rm_prec(i);
 529       return;
 530     }
 531     if (_in[i] != NULL) _in[i]->del_out((Node *)this);
 532     _in[i] = n;
 533     if (n != NULL) n->add_out((Node *)this);
 534   }
 535 
 536   // Set this node's index, used by cisc_version to replace current node
 537   void set_idx(uint new_idx) {
 538     const node_idx_t* ref = &_idx;
 539     *(node_idx_t*)ref = new_idx;
 540   }
 541   // Swap input edge order.  (Edge indexes i1 and i2 are usually 1 and 2.)
 542   void swap_edges(uint i1, uint i2) {
 543     debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
 544     // Def-Use info is unchanged
 545     Node* n1 = in(i1);
 546     Node* n2 = in(i2);
 547     _in[i1] = n2;
 548     _in[i2] = n1;
 549     // If this node is in the hash table, make sure it doesn't need a rehash.
 550     assert(check_hash == NO_HASH || check_hash == hash(), "edge swap must preserve hash code");
 551   }
 552 
 553   // Iterators over input Nodes for a Node X are written as:
 554   // for( i = 0; i < X.req(); i++ ) ... X[i] ...
 555   // NOTE: Required edges can contain embedded NULL pointers.
 556 
 557 //----------------- Other Node Properties
 558 
 559   // Generate class id for some ideal nodes to avoid virtual query
 560   // methods is_<Node>().
 561   // Class id is the set of bits corresponded to the node class and all its
 562   // super classes so that queries for super classes are also valid.
 563   // Subclasses of the same super class have different assigned bit
 564   // (the third parameter in the macro DEFINE_CLASS_ID).
 565   // Classes with deeper hierarchy are declared first.
 566   // Classes with the same hierarchy depth are sorted by usage frequency.
 567   //
 568   // The query method masks the bits to cut off bits of subclasses
 569   // and then compare the result with the class id
 570   // (see the macro DEFINE_CLASS_QUERY below).
 571   //
 572   //  Class_MachCall=30, ClassMask_MachCall=31
 573   // 12               8               4               0
 574   //  0   0   0   0   0   0   0   0   1   1   1   1   0
 575   //                                  |   |   |   |
 576   //                                  |   |   |   Bit_Mach=2
 577   //                                  |   |   Bit_MachReturn=4
 578   //                                  |   Bit_MachSafePoint=8
 579   //                                  Bit_MachCall=16
 580   //
 581   //  Class_CountedLoop=56, ClassMask_CountedLoop=63
 582   // 12               8               4               0
 583   //  0   0   0   0   0   0   0   1   1   1   0   0   0
 584   //                              |   |   |
 585   //                              |   |   Bit_Region=8
 586   //                              |   Bit_Loop=16
 587   //                              Bit_CountedLoop=32
 588 
 589   #define DEFINE_CLASS_ID(cl, supcl, subn) \
 590   Bit_##cl = (Class_##supcl == 0) ? 1 << subn : (Bit_##supcl) << (1 + subn) , \
 591   Class_##cl = Class_##supcl + Bit_##cl , \
 592   ClassMask_##cl = ((Bit_##cl << 1) - 1) ,
 593 
 594   // This enum is used only for C2 ideal and mach nodes with is_<node>() methods
 595   // so that it's values fits into 16 bits.
 596   enum NodeClasses {
 597     Bit_Node   = 0x0000,
 598     Class_Node = 0x0000,
 599     ClassMask_Node = 0xFFFF,
 600 
 601     DEFINE_CLASS_ID(Multi, Node, 0)
 602       DEFINE_CLASS_ID(SafePoint, Multi, 0)
 603         DEFINE_CLASS_ID(Call,      SafePoint, 0)
 604           DEFINE_CLASS_ID(CallJava,         Call, 0)
 605             DEFINE_CLASS_ID(CallStaticJava,   CallJava, 0)
 606             DEFINE_CLASS_ID(CallDynamicJava,  CallJava, 1)
 607           DEFINE_CLASS_ID(CallRuntime,      Call, 1)
 608             DEFINE_CLASS_ID(CallLeaf,         CallRuntime, 0)
 609           DEFINE_CLASS_ID(Allocate,         Call, 2)
 610             DEFINE_CLASS_ID(AllocateArray,    Allocate, 0)
 611           DEFINE_CLASS_ID(AbstractLock,     Call, 3)
 612             DEFINE_CLASS_ID(Lock,             AbstractLock, 0)
 613             DEFINE_CLASS_ID(Unlock,           AbstractLock, 1)
 614       DEFINE_CLASS_ID(MultiBranch, Multi, 1)
 615         DEFINE_CLASS_ID(PCTable,     MultiBranch, 0)
 616           DEFINE_CLASS_ID(Catch,       PCTable, 0)
 617           DEFINE_CLASS_ID(Jump,        PCTable, 1)
 618         DEFINE_CLASS_ID(If,          MultiBranch, 1)
 619           DEFINE_CLASS_ID(CountedLoopEnd, If, 0)
 620         DEFINE_CLASS_ID(NeverBranch, MultiBranch, 2)
 621       DEFINE_CLASS_ID(Start,       Multi, 2)
 622       DEFINE_CLASS_ID(MemBar,      Multi, 3)
 623         DEFINE_CLASS_ID(Initialize,       MemBar, 0)
 624         DEFINE_CLASS_ID(MemBarStoreStore, MemBar, 1)
 625 
 626     DEFINE_CLASS_ID(Mach,  Node, 1)
 627       DEFINE_CLASS_ID(MachReturn, Mach, 0)
 628         DEFINE_CLASS_ID(MachSafePoint, MachReturn, 0)
 629           DEFINE_CLASS_ID(MachCall, MachSafePoint, 0)
 630             DEFINE_CLASS_ID(MachCallJava,         MachCall, 0)
 631               DEFINE_CLASS_ID(MachCallStaticJava,   MachCallJava, 0)
 632               DEFINE_CLASS_ID(MachCallDynamicJava,  MachCallJava, 1)
 633             DEFINE_CLASS_ID(MachCallRuntime,      MachCall, 1)
 634               DEFINE_CLASS_ID(MachCallLeaf,         MachCallRuntime, 0)
 635       DEFINE_CLASS_ID(MachBranch, Mach, 1)
 636         DEFINE_CLASS_ID(MachIf,         MachBranch, 0)
 637         DEFINE_CLASS_ID(MachGoto,       MachBranch, 1)
 638         DEFINE_CLASS_ID(MachNullCheck,  MachBranch, 2)
 639       DEFINE_CLASS_ID(MachSpillCopy,    Mach, 2)
 640       DEFINE_CLASS_ID(MachTemp,         Mach, 3)
 641       DEFINE_CLASS_ID(MachConstantBase, Mach, 4)
 642       DEFINE_CLASS_ID(MachConstant,     Mach, 5)
 643       DEFINE_CLASS_ID(MachMerge,        Mach, 6)
 644       DEFINE_CLASS_ID(MachMemBar,       Mach, 7)
 645 
 646     DEFINE_CLASS_ID(Type,  Node, 2)
 647       DEFINE_CLASS_ID(Phi,   Type, 0)
 648       DEFINE_CLASS_ID(ConstraintCast, Type, 1)
 649         DEFINE_CLASS_ID(CastII, ConstraintCast, 0)
 650       DEFINE_CLASS_ID(CheckCastPP, Type, 2)
 651       DEFINE_CLASS_ID(CMove, Type, 3)
 652       DEFINE_CLASS_ID(SafePointScalarObject, Type, 4)
 653       DEFINE_CLASS_ID(DecodeNarrowPtr, Type, 5)
 654         DEFINE_CLASS_ID(DecodeN, DecodeNarrowPtr, 0)
 655         DEFINE_CLASS_ID(DecodeNKlass, DecodeNarrowPtr, 1)
 656       DEFINE_CLASS_ID(EncodeNarrowPtr, Type, 6)
 657         DEFINE_CLASS_ID(EncodeP, EncodeNarrowPtr, 0)
 658         DEFINE_CLASS_ID(EncodePKlass, EncodeNarrowPtr, 1)
 659       DEFINE_CLASS_ID(ShenandoahBarrier, Type, 7)
 660 
 661     DEFINE_CLASS_ID(Proj,  Node, 3)
 662       DEFINE_CLASS_ID(CatchProj, Proj, 0)
 663       DEFINE_CLASS_ID(JumpProj,  Proj, 1)
 664       DEFINE_CLASS_ID(IfProj,    Proj, 2)
 665         DEFINE_CLASS_ID(IfTrue,    IfProj, 0)
 666         DEFINE_CLASS_ID(IfFalse,   IfProj, 1)
 667       DEFINE_CLASS_ID(Parm,      Proj, 4)
 668       DEFINE_CLASS_ID(MachProj,  Proj, 5)
 669 
 670     DEFINE_CLASS_ID(Mem,   Node, 4)
 671       DEFINE_CLASS_ID(Load,  Mem, 0)
 672         DEFINE_CLASS_ID(LoadVector,  Load, 0)
 673       DEFINE_CLASS_ID(Store, Mem, 1)
 674         DEFINE_CLASS_ID(StoreVector, Store, 0)
 675       DEFINE_CLASS_ID(LoadStore, Mem, 2)
 676 
 677     DEFINE_CLASS_ID(Region, Node, 5)
 678       DEFINE_CLASS_ID(Loop, Region, 0)
 679         DEFINE_CLASS_ID(Root,        Loop, 0)
 680         DEFINE_CLASS_ID(CountedLoop, Loop, 1)
 681 
 682     DEFINE_CLASS_ID(Sub,   Node, 6)
 683       DEFINE_CLASS_ID(Cmp,   Sub, 0)
 684         DEFINE_CLASS_ID(FastLock,   Cmp, 0)
 685         DEFINE_CLASS_ID(FastUnlock, Cmp, 1)
 686 
 687     DEFINE_CLASS_ID(MergeMem, Node, 7)
 688     DEFINE_CLASS_ID(Bool,     Node, 8)
 689     DEFINE_CLASS_ID(AddP,     Node, 9)
 690     DEFINE_CLASS_ID(BoxLock,  Node, 10)
 691     DEFINE_CLASS_ID(Add,      Node, 11)
 692     DEFINE_CLASS_ID(Mul,      Node, 12)
 693     DEFINE_CLASS_ID(Vector,   Node, 13)
 694     DEFINE_CLASS_ID(ClearArray, Node, 14)
 695 
 696     _max_classes  = ClassMask_ClearArray
 697   };
 698   #undef DEFINE_CLASS_ID
 699 
 700   // Flags are sorted by usage frequency.
 701   enum NodeFlags {
 702     Flag_is_Copy                     = 0x01, // should be first bit to avoid shift
 703     Flag_rematerialize               = Flag_is_Copy << 1,
 704     Flag_needs_anti_dependence_check = Flag_rematerialize << 1,
 705     Flag_is_macro                    = Flag_needs_anti_dependence_check << 1,
 706     Flag_is_Con                      = Flag_is_macro << 1,
 707     Flag_is_cisc_alternate           = Flag_is_Con << 1,
 708     Flag_is_dead_loop_safe           = Flag_is_cisc_alternate << 1,
 709     Flag_may_be_short_branch         = Flag_is_dead_loop_safe << 1,
 710     Flag_avoid_back_to_back_before   = Flag_may_be_short_branch << 1,
 711     Flag_avoid_back_to_back_after    = Flag_avoid_back_to_back_before << 1,
 712     Flag_has_call                    = Flag_avoid_back_to_back_after << 1,
 713     Flag_is_expensive                = Flag_has_call << 1,
 714     _max_flags = (Flag_is_expensive << 1) - 1 // allow flags combination
 715   };
 716 
 717 private:
 718   jushort _class_id;
 719   jushort _flags;
 720 
 721 protected:
 722   // These methods should be called from constructors only.
 723   void init_class_id(jushort c) {
 724     assert(c <= _max_classes, "invalid node class");
 725     _class_id = c; // cast out const
 726   }
 727   void init_flags(jushort fl) {
 728     assert(fl <= _max_flags, "invalid node flag");
 729     _flags |= fl;
 730   }
 731   void clear_flag(jushort fl) {
 732     assert(fl <= _max_flags, "invalid node flag");
 733     _flags &= ~fl;
 734   }
 735 
 736 public:
 737   const jushort class_id() const { return _class_id; }
 738 
 739   const jushort flags() const { return _flags; }
 740 
 741   // Return a dense integer opcode number
 742   virtual int Opcode() const;
 743 
 744   // Virtual inherited Node size
 745   virtual uint size_of() const;
 746 
 747   // Other interesting Node properties
 748   #define DEFINE_CLASS_QUERY(type)                           \
 749   bool is_##type() const {                                   \
 750     return ((_class_id & ClassMask_##type) == Class_##type); \
 751   }                                                          \
 752   type##Node *as_##type() const {                            \
 753     assert(is_##type(), "invalid node class");               \
 754     return (type##Node*)this;                                \
 755   }                                                          \
 756   type##Node* isa_##type() const {                           \
 757     return (is_##type()) ? as_##type() : NULL;               \
 758   }
 759 
 760   DEFINE_CLASS_QUERY(AbstractLock)
 761   DEFINE_CLASS_QUERY(Add)
 762   DEFINE_CLASS_QUERY(AddP)
 763   DEFINE_CLASS_QUERY(Allocate)
 764   DEFINE_CLASS_QUERY(AllocateArray)
 765   DEFINE_CLASS_QUERY(Bool)
 766   DEFINE_CLASS_QUERY(BoxLock)
 767   DEFINE_CLASS_QUERY(Call)
 768   DEFINE_CLASS_QUERY(CallDynamicJava)
 769   DEFINE_CLASS_QUERY(CallJava)
 770   DEFINE_CLASS_QUERY(CallLeaf)
 771   DEFINE_CLASS_QUERY(CallRuntime)
 772   DEFINE_CLASS_QUERY(CallStaticJava)
 773   DEFINE_CLASS_QUERY(Catch)
 774   DEFINE_CLASS_QUERY(CatchProj)
 775   DEFINE_CLASS_QUERY(CheckCastPP)
 776   DEFINE_CLASS_QUERY(CastII)
 777   DEFINE_CLASS_QUERY(ConstraintCast)
 778   DEFINE_CLASS_QUERY(ClearArray)
 779   DEFINE_CLASS_QUERY(CMove)
 780   DEFINE_CLASS_QUERY(Cmp)
 781   DEFINE_CLASS_QUERY(CountedLoop)
 782   DEFINE_CLASS_QUERY(CountedLoopEnd)
 783   DEFINE_CLASS_QUERY(DecodeNarrowPtr)
 784   DEFINE_CLASS_QUERY(DecodeN)
 785   DEFINE_CLASS_QUERY(DecodeNKlass)
 786   DEFINE_CLASS_QUERY(EncodeNarrowPtr)
 787   DEFINE_CLASS_QUERY(EncodeP)
 788   DEFINE_CLASS_QUERY(EncodePKlass)
 789   DEFINE_CLASS_QUERY(FastLock)
 790   DEFINE_CLASS_QUERY(FastUnlock)
 791   DEFINE_CLASS_QUERY(If)
 792   DEFINE_CLASS_QUERY(IfProj)
 793   DEFINE_CLASS_QUERY(IfFalse)
 794   DEFINE_CLASS_QUERY(IfTrue)
 795   DEFINE_CLASS_QUERY(Initialize)
 796   DEFINE_CLASS_QUERY(Jump)
 797   DEFINE_CLASS_QUERY(JumpProj)
 798   DEFINE_CLASS_QUERY(Load)
 799   DEFINE_CLASS_QUERY(LoadStore)
 800   DEFINE_CLASS_QUERY(Lock)
 801   DEFINE_CLASS_QUERY(Loop)
 802   DEFINE_CLASS_QUERY(Mach)
 803   DEFINE_CLASS_QUERY(MachBranch)
 804   DEFINE_CLASS_QUERY(MachCall)
 805   DEFINE_CLASS_QUERY(MachCallDynamicJava)
 806   DEFINE_CLASS_QUERY(MachCallJava)
 807   DEFINE_CLASS_QUERY(MachCallLeaf)
 808   DEFINE_CLASS_QUERY(MachCallRuntime)
 809   DEFINE_CLASS_QUERY(MachCallStaticJava)
 810   DEFINE_CLASS_QUERY(MachConstantBase)
 811   DEFINE_CLASS_QUERY(MachConstant)
 812   DEFINE_CLASS_QUERY(MachGoto)
 813   DEFINE_CLASS_QUERY(MachIf)
 814   DEFINE_CLASS_QUERY(MachNullCheck)
 815   DEFINE_CLASS_QUERY(MachProj)
 816   DEFINE_CLASS_QUERY(MachReturn)
 817   DEFINE_CLASS_QUERY(MachSafePoint)
 818   DEFINE_CLASS_QUERY(MachSpillCopy)
 819   DEFINE_CLASS_QUERY(MachTemp)
 820   DEFINE_CLASS_QUERY(MachMemBar)
 821   DEFINE_CLASS_QUERY(MachMerge)
 822   DEFINE_CLASS_QUERY(Mem)
 823   DEFINE_CLASS_QUERY(MemBar)
 824   DEFINE_CLASS_QUERY(MemBarStoreStore)
 825   DEFINE_CLASS_QUERY(MergeMem)
 826   DEFINE_CLASS_QUERY(Mul)
 827   DEFINE_CLASS_QUERY(Multi)
 828   DEFINE_CLASS_QUERY(MultiBranch)
 829   DEFINE_CLASS_QUERY(Parm)
 830   DEFINE_CLASS_QUERY(PCTable)
 831   DEFINE_CLASS_QUERY(Phi)
 832   DEFINE_CLASS_QUERY(Proj)
 833   DEFINE_CLASS_QUERY(Region)
 834   DEFINE_CLASS_QUERY(Root)
 835   DEFINE_CLASS_QUERY(SafePoint)
 836   DEFINE_CLASS_QUERY(SafePointScalarObject)
 837   DEFINE_CLASS_QUERY(ShenandoahBarrier)
 838   DEFINE_CLASS_QUERY(Start)
 839   DEFINE_CLASS_QUERY(Store)
 840   DEFINE_CLASS_QUERY(Sub)
 841   DEFINE_CLASS_QUERY(Type)
 842   DEFINE_CLASS_QUERY(Vector)
 843   DEFINE_CLASS_QUERY(LoadVector)
 844   DEFINE_CLASS_QUERY(StoreVector)
 845   DEFINE_CLASS_QUERY(Unlock)
 846 
 847   #undef DEFINE_CLASS_QUERY
 848 
 849   // duplicate of is_MachSpillCopy()
 850   bool is_SpillCopy () const {
 851     return ((_class_id & ClassMask_MachSpillCopy) == Class_MachSpillCopy);
 852   }
 853 
 854   bool is_Con () const { return (_flags & Flag_is_Con) != 0; }
 855   // The data node which is safe to leave in dead loop during IGVN optimization.
 856   bool is_dead_loop_safe() const {
 857     return is_Phi() || (is_Proj() && in(0) == NULL) ||
 858            ((_flags & (Flag_is_dead_loop_safe | Flag_is_Con)) != 0 &&
 859             (!is_Proj() || !in(0)->is_Allocate()));
 860   }
 861 
 862   // is_Copy() returns copied edge index (0 or 1)
 863   uint is_Copy() const { return (_flags & Flag_is_Copy); }
 864 
 865   virtual bool is_CFG() const { return false; }
 866 
 867   // If this node is control-dependent on a test, can it be
 868   // rerouted to a dominating equivalent test?  This is usually
 869   // true of non-CFG nodes, but can be false for operations which
 870   // depend for their correct sequencing on more than one test.
 871   // (In that case, hoisting to a dominating test may silently
 872   // skip some other important test.)
 873   virtual bool depends_only_on_test() const { assert(!is_CFG(), ""); return true; };
 874 
 875   // When building basic blocks, I need to have a notion of block beginning
 876   // Nodes, next block selector Nodes (block enders), and next block
 877   // projections.  These calls need to work on their machine equivalents.  The
 878   // Ideal beginning Nodes are RootNode, RegionNode and StartNode.
 879   bool is_block_start() const {
 880     if ( is_Region() )
 881       return this == (const Node*)in(0);
 882     else
 883       return is_Start();
 884   }
 885 
 886   // The Ideal control projection Nodes are IfTrue/IfFalse, JumpProjNode, Root,
 887   // Goto and Return.  This call also returns the block ending Node.
 888   virtual const Node *is_block_proj() const;
 889 
 890   // The node is a "macro" node which needs to be expanded before matching
 891   bool is_macro() const { return (_flags & Flag_is_macro) != 0; }
 892   // The node is expensive: the best control is set during loop opts
 893   bool is_expensive() const { return (_flags & Flag_is_expensive) != 0 && in(0) != NULL; }
 894 
 895 //----------------- Optimization
 896 
 897   // Get the worst-case Type output for this Node.
 898   virtual const class Type *bottom_type() const;
 899 
 900   // If we find a better type for a node, try to record it permanently.
 901   // Return true if this node actually changed.
 902   // Be sure to do the hash_delete game in the "rehash" variant.
 903   void raise_bottom_type(const Type* new_type);
 904 
 905   // Get the address type with which this node uses and/or defs memory,
 906   // or NULL if none.  The address type is conservatively wide.
 907   // Returns non-null for calls, membars, loads, stores, etc.
 908   // Returns TypePtr::BOTTOM if the node touches memory "broadly".
 909   virtual const class TypePtr *adr_type() const { return NULL; }
 910 
 911   // Return an existing node which computes the same function as this node.
 912   // The optimistic combined algorithm requires this to return a Node which
 913   // is a small number of steps away (e.g., one of my inputs).
 914   virtual Node *Identity( PhaseTransform *phase );
 915 
 916   // Return the set of values this Node can take on at runtime.
 917   virtual const Type *Value( PhaseTransform *phase ) const;
 918 
 919   // Return a node which is more "ideal" than the current node.
 920   // The invariants on this call are subtle.  If in doubt, read the
 921   // treatise in node.cpp above the default implemention AND TEST WITH
 922   // +VerifyIterativeGVN!
 923   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 924 
 925   // Some nodes have specific Ideal subgraph transformations only if they are
 926   // unique users of specific nodes. Such nodes should be put on IGVN worklist
 927   // for the transformations to happen.
 928   bool has_special_unique_user() const;
 929 
 930   // Skip Proj and CatchProj nodes chains. Check for Null and Top.
 931   Node* find_exact_control(Node* ctrl);
 932 
 933   // Check if 'this' node dominates or equal to 'sub'.
 934   bool dominates(Node* sub, Node_List &nlist);
 935 
 936   virtual bool is_g1_wb_pre_call() const { return false; }
 937   virtual bool is_shenandoah_state_load() const { return false; }
 938   virtual bool is_shenandoah_marking_if(PhaseTransform *phase) const { return false; }
 939 
 940 protected:
 941   bool remove_dead_region(PhaseGVN *phase, bool can_reshape);
 942 public:
 943 



 944   // See if there is valid pipeline info
 945   static  const Pipeline *pipeline_class();
 946   virtual const Pipeline *pipeline() const;
 947 
 948   // Compute the latency from the def to this instruction of the ith input node
 949   uint latency(uint i);
 950 
 951   // Hash & compare functions, for pessimistic value numbering
 952 
 953   // If the hash function returns the special sentinel value NO_HASH,
 954   // the node is guaranteed never to compare equal to any other node.
 955   // If we accidentally generate a hash with value NO_HASH the node
 956   // won't go into the table and we'll lose a little optimization.
 957   enum { NO_HASH = 0 };
 958   virtual uint hash() const;
 959   virtual uint cmp( const Node &n ) const;
 960 
 961   // Operation appears to be iteratively computed (such as an induction variable)
 962   // It is possible for this operation to return false for a loop-varying
 963   // value, if it appears (by local graph inspection) to be computed by a simple conditional.
 964   bool is_iteratively_computed();
 965 
 966   // Determine if a node is Counted loop induction variable.
 967   // The method is defined in loopnode.cpp.
 968   const Node* is_loop_iv() const;
 969 
 970   // Return a node with opcode "opc" and same inputs as "this" if one can
 971   // be found; Otherwise return NULL;
 972   Node* find_similar(int opc);
 973 
 974   // Return the unique control out if only one. Null if none or more than one.
 975   Node* unique_ctrl_out();
 976 
 977   // Set control or add control as precedence edge
 978   void ensure_control_or_add_prec(Node* c);
 979 
 980 //----------------- Code Generation
 981 
 982   // Ideal register class for Matching.  Zero means unmatched instruction
 983   // (these are cloned instead of converted to machine nodes).
 984   virtual uint ideal_reg() const;
 985 
 986   static const uint NotAMachineReg;   // must be > max. machine register
 987 
 988   // Do we Match on this edge index or not?  Generally false for Control
 989   // and true for everything else.  Weird for calls & returns.
 990   virtual uint match_edge(uint idx) const;
 991 
 992   // Register class output is returned in
 993   virtual const RegMask &out_RegMask() const;
 994   // Register class input is expected in
 995   virtual const RegMask &in_RegMask(uint) const;
 996   // Should we clone rather than spill this instruction?
 997   bool rematerialize() const;
 998 
 999   // Return JVM State Object if this Node carries debug info, or NULL otherwise
1000   virtual JVMState* jvms() const;
1001 
1002   // Print as assembly
1003   virtual void format( PhaseRegAlloc *, outputStream* st = tty ) const;
1004   // Emit bytes starting at parameter 'ptr'
1005   // Bump 'ptr' by the number of output bytes
1006   virtual void emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const;
1007   // Size of instruction in bytes
1008   virtual uint size(PhaseRegAlloc *ra_) const;
1009 
1010   // Convenience function to extract an integer constant from a node.
1011   // If it is not an integer constant (either Con, CastII, or Mach),
1012   // return value_if_unknown.
1013   jint find_int_con(jint value_if_unknown) const {
1014     const TypeInt* t = find_int_type();
1015     return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown;
1016   }
1017   // Return the constant, knowing it is an integer constant already
1018   jint get_int() const {
1019     const TypeInt* t = find_int_type();
1020     guarantee(t != NULL, "must be con");
1021     return t->get_con();
1022   }
1023   // Here's where the work is done.  Can produce non-constant int types too.
1024   const TypeInt* find_int_type() const;
1025 
1026   // Same thing for long (and intptr_t, via type.hpp):
1027   jlong get_long() const {
1028     const TypeLong* t = find_long_type();
1029     guarantee(t != NULL, "must be con");
1030     return t->get_con();
1031   }
1032   jlong find_long_con(jint value_if_unknown) const {
1033     const TypeLong* t = find_long_type();
1034     return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown;
1035   }
1036   const TypeLong* find_long_type() const;
1037 
1038   const TypePtr* get_ptr_type() const;
1039 
1040   // These guys are called by code generated by ADLC:
1041   intptr_t get_ptr() const;
1042   intptr_t get_narrowcon() const;
1043   jdouble getd() const;
1044   jfloat getf() const;
1045 
1046   // Nodes which are pinned into basic blocks
1047   virtual bool pinned() const { return false; }
1048 
1049   // Nodes which use memory without consuming it, hence need antidependences
1050   // More specifically, needs_anti_dependence_check returns true iff the node
1051   // (a) does a load, and (b) does not perform a store (except perhaps to a
1052   // stack slot or some other unaliased location).
1053   bool needs_anti_dependence_check() const;
1054 
1055   // Return which operand this instruction may cisc-spill. In other words,
1056   // return operand position that can convert from reg to memory access
1057   virtual int cisc_operand() const { return AdlcVMDeps::Not_cisc_spillable; }
1058   bool is_cisc_alternate() const { return (_flags & Flag_is_cisc_alternate) != 0; }
1059 
1060 //----------------- Graph walking
1061 public:
1062   // Walk and apply member functions recursively.
1063   // Supplied (this) pointer is root.
1064   void walk(NFunc pre, NFunc post, void *env);
1065   static void nop(Node &, void*); // Dummy empty function
1066   static void packregion( Node &n, void* );
1067 private:
1068   void walk_(NFunc pre, NFunc post, void *env, VectorSet &visited);
1069 
1070 //----------------- Printing, etc
1071 public:
1072 #ifndef PRODUCT
1073   Node* find(int idx) const;         // Search the graph for the given idx.
1074   Node* find_ctrl(int idx) const;    // Search control ancestors for the given idx.
1075   void dump() const { dump("\n"); }  // Print this node.
1076   void dump(const char* suffix, outputStream *st = tty) const;// Print this node.
1077   void dump(int depth) const;        // Print this node, recursively to depth d
1078   void dump_ctrl(int depth) const;   // Print control nodes, to depth d
1079   virtual void dump_req(outputStream *st = tty) const;     // Print required-edge info
1080   virtual void dump_prec(outputStream *st = tty) const;    // Print precedence-edge info
1081   virtual void dump_out(outputStream *st = tty) const;     // Print the output edge info
1082   virtual void dump_spec(outputStream *st) const {}; // Print per-node info
1083   void verify_edges(Unique_Node_List &visited); // Verify bi-directional edges
1084   void verify() const;               // Check Def-Use info for my subgraph
1085   static void verify_recur(const Node *n, int verify_depth, VectorSet &old_space, VectorSet &new_space);
1086 
1087   // This call defines a class-unique string used to identify class instances
1088   virtual const char *Name() const;
1089 
1090   void dump_format(PhaseRegAlloc *ra) const; // debug access to MachNode::format(...)
1091   // RegMask Print Functions
1092   void dump_in_regmask(int idx) { in_RegMask(idx).dump(); }
1093   void dump_out_regmask() { out_RegMask().dump(); }
1094   static bool in_dump() { return Compile::current()->_in_dump_cnt > 0; }
1095   void fast_dump() const {
1096     tty->print("%4d: %-17s", _idx, Name());
1097     for (uint i = 0; i < len(); i++)
1098       if (in(i))
1099         tty->print(" %4d", in(i)->_idx);
1100       else
1101         tty->print(" NULL");
1102     tty->print("\n");
1103   }
1104 #endif
1105 #ifdef ASSERT
1106   void verify_construction();
1107   bool verify_jvms(const JVMState* jvms) const;
1108   int  _debug_idx;                     // Unique value assigned to every node.
1109   int   debug_idx() const              { return _debug_idx; }
1110   void  set_debug_idx( int debug_idx ) { _debug_idx = debug_idx; }
1111 
1112   Node* _debug_orig;                   // Original version of this, if any.
1113   Node*  debug_orig() const            { return _debug_orig; }
1114   void   set_debug_orig(Node* orig);   // _debug_orig = orig
1115 
1116   int        _hash_lock;               // Barrier to modifications of nodes in the hash table
1117   void  enter_hash_lock() { ++_hash_lock; assert(_hash_lock < 99, "in too many hash tables?"); }
1118   void   exit_hash_lock() { --_hash_lock; assert(_hash_lock >= 0, "mispaired hash locks"); }
1119 
1120   static void init_NodeProperty();
1121 
1122   #if OPTO_DU_ITERATOR_ASSERT
1123   const Node* _last_del;               // The last deleted node.
1124   uint        _del_tick;               // Bumped when a deletion happens..
1125   #endif
1126 #endif
1127 };
1128 
1129 //-----------------------------------------------------------------------------
1130 // Iterators over DU info, and associated Node functions.
1131 
1132 #if OPTO_DU_ITERATOR_ASSERT
1133 
1134 // Common code for assertion checking on DU iterators.
1135 class DUIterator_Common VALUE_OBJ_CLASS_SPEC {
1136 #ifdef ASSERT
1137  protected:
1138   bool         _vdui;               // cached value of VerifyDUIterators
1139   const Node*  _node;               // the node containing the _out array
1140   uint         _outcnt;             // cached node->_outcnt
1141   uint         _del_tick;           // cached node->_del_tick
1142   Node*        _last;               // last value produced by the iterator
1143 
1144   void sample(const Node* node);    // used by c'tor to set up for verifies
1145   void verify(const Node* node, bool at_end_ok = false);
1146   void verify_resync();
1147   void reset(const DUIterator_Common& that);
1148 
1149 // The VDUI_ONLY macro protects code conditionalized on VerifyDUIterators
1150   #define I_VDUI_ONLY(i,x) { if ((i)._vdui) { x; } }
1151 #else
1152   #define I_VDUI_ONLY(i,x) { }
1153 #endif //ASSERT
1154 };
1155 
1156 #define VDUI_ONLY(x)     I_VDUI_ONLY(*this, x)
1157 
1158 // Default DU iterator.  Allows appends onto the out array.
1159 // Allows deletion from the out array only at the current point.
1160 // Usage:
1161 //  for (DUIterator i = x->outs(); x->has_out(i); i++) {
1162 //    Node* y = x->out(i);
1163 //    ...
1164 //  }
1165 // Compiles in product mode to a unsigned integer index, which indexes
1166 // onto a repeatedly reloaded base pointer of x->_out.  The loop predicate
1167 // also reloads x->_outcnt.  If you delete, you must perform "--i" just
1168 // before continuing the loop.  You must delete only the last-produced
1169 // edge.  You must delete only a single copy of the last-produced edge,
1170 // or else you must delete all copies at once (the first time the edge
1171 // is produced by the iterator).
1172 class DUIterator : public DUIterator_Common {
1173   friend class Node;
1174 
1175   // This is the index which provides the product-mode behavior.
1176   // Whatever the product-mode version of the system does to the
1177   // DUI index is done to this index.  All other fields in
1178   // this class are used only for assertion checking.
1179   uint         _idx;
1180 
1181   #ifdef ASSERT
1182   uint         _refresh_tick;    // Records the refresh activity.
1183 
1184   void sample(const Node* node); // Initialize _refresh_tick etc.
1185   void verify(const Node* node, bool at_end_ok = false);
1186   void verify_increment();       // Verify an increment operation.
1187   void verify_resync();          // Verify that we can back up over a deletion.
1188   void verify_finish();          // Verify that the loop terminated properly.
1189   void refresh();                // Resample verification info.
1190   void reset(const DUIterator& that);  // Resample after assignment.
1191   #endif
1192 
1193   DUIterator(const Node* node, int dummy_to_avoid_conversion)
1194     { _idx = 0;                         debug_only(sample(node)); }
1195 
1196  public:
1197   // initialize to garbage; clear _vdui to disable asserts
1198   DUIterator()
1199     { /*initialize to garbage*/         debug_only(_vdui = false); }
1200 
1201   void operator++(int dummy_to_specify_postfix_op)
1202     { _idx++;                           VDUI_ONLY(verify_increment()); }
1203 
1204   void operator--()
1205     { VDUI_ONLY(verify_resync());       --_idx; }
1206 
1207   ~DUIterator()
1208     { VDUI_ONLY(verify_finish()); }
1209 
1210   void operator=(const DUIterator& that)
1211     { _idx = that._idx;                 debug_only(reset(that)); }
1212 };
1213 
1214 DUIterator Node::outs() const
1215   { return DUIterator(this, 0); }
1216 DUIterator& Node::refresh_out_pos(DUIterator& i) const
1217   { I_VDUI_ONLY(i, i.refresh());        return i; }
1218 bool Node::has_out(DUIterator& i) const
1219   { I_VDUI_ONLY(i, i.verify(this,true));return i._idx < _outcnt; }
1220 Node*    Node::out(DUIterator& i) const
1221   { I_VDUI_ONLY(i, i.verify(this));     return debug_only(i._last=) _out[i._idx]; }
1222 
1223 
1224 // Faster DU iterator.  Disallows insertions into the out array.
1225 // Allows deletion from the out array only at the current point.
1226 // Usage:
1227 //  for (DUIterator_Fast imax, i = x->fast_outs(imax); i < imax; i++) {
1228 //    Node* y = x->fast_out(i);
1229 //    ...
1230 //  }
1231 // Compiles in product mode to raw Node** pointer arithmetic, with
1232 // no reloading of pointers from the original node x.  If you delete,
1233 // you must perform "--i; --imax" just before continuing the loop.
1234 // If you delete multiple copies of the same edge, you must decrement
1235 // imax, but not i, multiple times:  "--i, imax -= num_edges".
1236 class DUIterator_Fast : public DUIterator_Common {
1237   friend class Node;
1238   friend class DUIterator_Last;
1239 
1240   // This is the pointer which provides the product-mode behavior.
1241   // Whatever the product-mode version of the system does to the
1242   // DUI pointer is done to this pointer.  All other fields in
1243   // this class are used only for assertion checking.
1244   Node**       _outp;
1245 
1246   #ifdef ASSERT
1247   void verify(const Node* node, bool at_end_ok = false);
1248   void verify_limit();
1249   void verify_resync();
1250   void verify_relimit(uint n);
1251   void reset(const DUIterator_Fast& that);
1252   #endif
1253 
1254   // Note:  offset must be signed, since -1 is sometimes passed
1255   DUIterator_Fast(const Node* node, ptrdiff_t offset)
1256     { _outp = node->_out + offset;      debug_only(sample(node)); }
1257 
1258  public:
1259   // initialize to garbage; clear _vdui to disable asserts
1260   DUIterator_Fast()
1261     { /*initialize to garbage*/         debug_only(_vdui = false); }
1262 
1263   void operator++(int dummy_to_specify_postfix_op)
1264     { _outp++;                          VDUI_ONLY(verify(_node, true)); }
1265 
1266   void operator--()
1267     { VDUI_ONLY(verify_resync());       --_outp; }
1268 
1269   void operator-=(uint n)   // applied to the limit only
1270     { _outp -= n;           VDUI_ONLY(verify_relimit(n));  }
1271 
1272   bool operator<(DUIterator_Fast& limit) {
1273     I_VDUI_ONLY(*this, this->verify(_node, true));
1274     I_VDUI_ONLY(limit, limit.verify_limit());
1275     return _outp < limit._outp;
1276   }
1277 
1278   void operator=(const DUIterator_Fast& that)
1279     { _outp = that._outp;               debug_only(reset(that)); }
1280 };
1281 
1282 DUIterator_Fast Node::fast_outs(DUIterator_Fast& imax) const {
1283   // Assign a limit pointer to the reference argument:
1284   imax = DUIterator_Fast(this, (ptrdiff_t)_outcnt);
1285   // Return the base pointer:
1286   return DUIterator_Fast(this, 0);
1287 }
1288 Node* Node::fast_out(DUIterator_Fast& i) const {
1289   I_VDUI_ONLY(i, i.verify(this));
1290   return debug_only(i._last=) *i._outp;
1291 }
1292 
1293 
1294 // Faster DU iterator.  Requires each successive edge to be removed.
1295 // Does not allow insertion of any edges.
1296 // Usage:
1297 //  for (DUIterator_Last imin, i = x->last_outs(imin); i >= imin; i -= num_edges) {
1298 //    Node* y = x->last_out(i);
1299 //    ...
1300 //  }
1301 // Compiles in product mode to raw Node** pointer arithmetic, with
1302 // no reloading of pointers from the original node x.
1303 class DUIterator_Last : private DUIterator_Fast {
1304   friend class Node;
1305 
1306   #ifdef ASSERT
1307   void verify(const Node* node, bool at_end_ok = false);
1308   void verify_limit();
1309   void verify_step(uint num_edges);
1310   #endif
1311 
1312   // Note:  offset must be signed, since -1 is sometimes passed
1313   DUIterator_Last(const Node* node, ptrdiff_t offset)
1314     : DUIterator_Fast(node, offset) { }
1315 
1316   void operator++(int dummy_to_specify_postfix_op) {} // do not use
1317   void operator<(int)                              {} // do not use
1318 
1319  public:
1320   DUIterator_Last() { }
1321   // initialize to garbage
1322 
1323   void operator--()
1324     { _outp--;              VDUI_ONLY(verify_step(1));  }
1325 
1326   void operator-=(uint n)
1327     { _outp -= n;           VDUI_ONLY(verify_step(n));  }
1328 
1329   bool operator>=(DUIterator_Last& limit) {
1330     I_VDUI_ONLY(*this, this->verify(_node, true));
1331     I_VDUI_ONLY(limit, limit.verify_limit());
1332     return _outp >= limit._outp;
1333   }
1334 
1335   void operator=(const DUIterator_Last& that)
1336     { DUIterator_Fast::operator=(that); }
1337 };
1338 
1339 DUIterator_Last Node::last_outs(DUIterator_Last& imin) const {
1340   // Assign a limit pointer to the reference argument:
1341   imin = DUIterator_Last(this, 0);
1342   // Return the initial pointer:
1343   return DUIterator_Last(this, (ptrdiff_t)_outcnt - 1);
1344 }
1345 Node* Node::last_out(DUIterator_Last& i) const {
1346   I_VDUI_ONLY(i, i.verify(this));
1347   return debug_only(i._last=) *i._outp;
1348 }
1349 
1350 #endif //OPTO_DU_ITERATOR_ASSERT
1351 
1352 #undef I_VDUI_ONLY
1353 #undef VDUI_ONLY
1354 
1355 // An Iterator that truly follows the iterator pattern.  Doesn't
1356 // support deletion but could be made to.
1357 //
1358 //   for (SimpleDUIterator i(n); i.has_next(); i.next()) {
1359 //     Node* m = i.get();
1360 //
1361 class SimpleDUIterator : public StackObj {
1362  private:
1363   Node* node;
1364   DUIterator_Fast i;
1365   DUIterator_Fast imax;
1366  public:
1367   SimpleDUIterator(Node* n): node(n), i(n->fast_outs(imax)) {}
1368   bool has_next() { return i < imax; }
1369   void next() { i++; }
1370   Node* get() { return node->fast_out(i); }
1371 };
1372 
1373 
1374 //-----------------------------------------------------------------------------
1375 // Map dense integer indices to Nodes.  Uses classic doubling-array trick.
1376 // Abstractly provides an infinite array of Node*'s, initialized to NULL.
1377 // Note that the constructor just zeros things, and since I use Arena
1378 // allocation I do not need a destructor to reclaim storage.
1379 class Node_Array : public ResourceObj {
1380   friend class VMStructs;
1381 protected:
1382   Arena *_a;                    // Arena to allocate in
1383   uint   _max;
1384   Node **_nodes;
1385   void   grow( uint i );        // Grow array node to fit
1386 public:
1387   Node_Array(Arena *a) : _a(a), _max(OptoNodeListSize) {
1388     _nodes = NEW_ARENA_ARRAY( a, Node *, OptoNodeListSize );
1389     for( int i = 0; i < OptoNodeListSize; i++ ) {
1390       _nodes[i] = NULL;
1391     }
1392   }
1393 
1394   Node_Array(Node_Array *na) : _a(na->_a), _max(na->_max), _nodes(na->_nodes) {}
1395   Node *operator[] ( uint i ) const // Lookup, or NULL for not mapped
1396   { return (i<_max) ? _nodes[i] : (Node*)NULL; }
1397   Node *at( uint i ) const { assert(i<_max,"oob"); return _nodes[i]; }
1398   Node **adr() { return _nodes; }
1399   // Extend the mapping: index i maps to Node *n.
1400   void map( uint i, Node *n ) { if( i>=_max ) grow(i); _nodes[i] = n; }
1401   void insert( uint i, Node *n );
1402   void remove( uint i );        // Remove, preserving order
1403   void sort( C_sort_func_t func);
1404   void reset( Arena *new_a );   // Zap mapping to empty; reclaim storage
1405   void clear();                 // Set all entries to NULL, keep storage
1406   uint Size() const { return _max; }
1407   void dump() const;
1408 };
1409 
1410 class Node_List : public Node_Array {
1411   friend class VMStructs;
1412   uint _cnt;
1413 public:
1414   Node_List() : Node_Array(Thread::current()->resource_area()), _cnt(0) {}
1415   Node_List(Arena *a) : Node_Array(a), _cnt(0) {}
1416   bool contains(const Node* n) const {
1417     for (uint e = 0; e < size(); e++) {
1418       if (at(e) == n) return true;
1419     }
1420     return false;
1421   }
1422   void insert( uint i, Node *n ) { Node_Array::insert(i,n); _cnt++; }
1423   void remove( uint i ) { Node_Array::remove(i); _cnt--; }
1424   void push( Node *b ) { map(_cnt++,b); }
1425   void yank( Node *n );         // Find and remove
1426   Node *pop() { return _nodes[--_cnt]; }
1427   Node *rpop() { Node *b = _nodes[0]; _nodes[0]=_nodes[--_cnt]; return b;}
1428   void clear() { _cnt = 0; Node_Array::clear(); } // retain storage
1429   uint size() const { return _cnt; }
1430   void dump() const;
1431   void dump_simple() const;
1432 };
1433 
1434 //------------------------------Unique_Node_List-------------------------------
1435 class Unique_Node_List : public Node_List {
1436   friend class VMStructs;
1437   VectorSet _in_worklist;
1438   uint _clock_index;            // Index in list where to pop from next
1439 public:
1440   Unique_Node_List() : Node_List(), _in_worklist(Thread::current()->resource_area()), _clock_index(0) {}
1441   Unique_Node_List(Arena *a) : Node_List(a), _in_worklist(a), _clock_index(0) {}
1442 
1443   void remove( Node *n );
1444   bool member( Node *n ) { return _in_worklist.test(n->_idx) != 0; }
1445   VectorSet &member_set(){ return _in_worklist; }
1446 
1447   void push( Node *b ) {
1448     if( !_in_worklist.test_set(b->_idx) )
1449       Node_List::push(b);
1450   }
1451   Node *pop() {
1452     if( _clock_index >= size() ) _clock_index = 0;
1453     Node *b = at(_clock_index);
1454     map( _clock_index, Node_List::pop());
1455     if (size() != 0) _clock_index++; // Always start from 0
1456     _in_worklist >>= b->_idx;
1457     return b;
1458   }
1459   Node *remove( uint i ) {
1460     Node *b = Node_List::at(i);
1461     _in_worklist >>= b->_idx;
1462     map(i,Node_List::pop());
1463     return b;
1464   }
1465   void yank( Node *n ) { _in_worklist >>= n->_idx; Node_List::yank(n); }
1466   void  clear() {
1467     _in_worklist.Clear();        // Discards storage but grows automatically
1468     Node_List::clear();
1469     _clock_index = 0;
1470   }
1471 
1472   // Used after parsing to remove useless nodes before Iterative GVN
1473   void remove_useless_nodes(VectorSet &useful);
1474 
1475 #ifndef PRODUCT
1476   void print_set() const { _in_worklist.print(); }
1477 #endif
1478 };
1479 
1480 // Inline definition of Compile::record_for_igvn must be deferred to this point.
1481 inline void Compile::record_for_igvn(Node* n) {
1482   _for_igvn->push(n);
1483 }
1484 
1485 //------------------------------Node_Stack-------------------------------------
1486 class Node_Stack {
1487   friend class VMStructs;
1488 protected:
1489   struct INode {
1490     Node *node; // Processed node
1491     uint  indx; // Index of next node's child
1492   };
1493   INode *_inode_top; // tos, stack grows up
1494   INode *_inode_max; // End of _inodes == _inodes + _max
1495   INode *_inodes;    // Array storage for the stack
1496   Arena *_a;         // Arena to allocate in
1497   void grow();
1498 public:
1499   Node_Stack(int size) {
1500     size_t max = (size > OptoNodeListSize) ? size : OptoNodeListSize;
1501     _a = Thread::current()->resource_area();
1502     _inodes = NEW_ARENA_ARRAY( _a, INode, max );
1503     _inode_max = _inodes + max;
1504     _inode_top = _inodes - 1; // stack is empty
1505   }
1506 
1507   Node_Stack(Arena *a, int size) : _a(a) {
1508     size_t max = (size > OptoNodeListSize) ? size : OptoNodeListSize;
1509     _inodes = NEW_ARENA_ARRAY( _a, INode, max );
1510     _inode_max = _inodes + max;
1511     _inode_top = _inodes - 1; // stack is empty
1512   }
1513 
1514   void pop() {
1515     assert(_inode_top >= _inodes, "node stack underflow");
1516     --_inode_top;
1517   }
1518   void push(Node *n, uint i) {
1519     ++_inode_top;
1520     if (_inode_top >= _inode_max) grow();
1521     INode *top = _inode_top; // optimization
1522     top->node = n;
1523     top->indx = i;
1524   }
1525   Node *node() const {
1526     return _inode_top->node;
1527   }
1528   Node* node_at(uint i) const {
1529     assert(_inodes + i <= _inode_top, "in range");
1530     return _inodes[i].node;
1531   }
1532   uint index() const {
1533     return _inode_top->indx;
1534   }
1535   uint index_at(uint i) const {
1536     assert(_inodes + i <= _inode_top, "in range");
1537     return _inodes[i].indx;
1538   }
1539   void set_node(Node *n) {
1540     _inode_top->node = n;
1541   }
1542   void set_index(uint i) {
1543     _inode_top->indx = i;
1544   }
1545   uint size_max() const { return (uint)pointer_delta(_inode_max, _inodes,  sizeof(INode)); } // Max size
1546   uint size() const { return (uint)pointer_delta((_inode_top+1), _inodes,  sizeof(INode)); } // Current size
1547   bool is_nonempty() const { return (_inode_top >= _inodes); }
1548   bool is_empty() const { return (_inode_top < _inodes); }
1549   void clear() { _inode_top = _inodes - 1; } // retain storage
1550 
1551   // Node_Stack is used to map nodes.
1552   Node* find(uint idx) const;
1553 };
1554 
1555 
1556 //-----------------------------Node_Notes--------------------------------------
1557 // Debugging or profiling annotations loosely and sparsely associated
1558 // with some nodes.  See Compile::node_notes_at for the accessor.
1559 class Node_Notes VALUE_OBJ_CLASS_SPEC {
1560   friend class VMStructs;
1561   JVMState* _jvms;
1562 
1563 public:
1564   Node_Notes(JVMState* jvms = NULL) {
1565     _jvms = jvms;
1566   }
1567 
1568   JVMState* jvms()            { return _jvms; }
1569   void  set_jvms(JVMState* x) {        _jvms = x; }
1570 
1571   // True if there is nothing here.
1572   bool is_clear() {
1573     return (_jvms == NULL);
1574   }
1575 
1576   // Make there be nothing here.
1577   void clear() {
1578     _jvms = NULL;
1579   }
1580 
1581   // Make a new, clean node notes.
1582   static Node_Notes* make(Compile* C) {
1583     Node_Notes* nn = NEW_ARENA_ARRAY(C->comp_arena(), Node_Notes, 1);
1584     nn->clear();
1585     return nn;
1586   }
1587 
1588   Node_Notes* clone(Compile* C) {
1589     Node_Notes* nn = NEW_ARENA_ARRAY(C->comp_arena(), Node_Notes, 1);
1590     (*nn) = (*this);
1591     return nn;
1592   }
1593 
1594   // Absorb any information from source.
1595   bool update_from(Node_Notes* source) {
1596     bool changed = false;
1597     if (source != NULL) {
1598       if (source->jvms() != NULL) {
1599         set_jvms(source->jvms());
1600         changed = true;
1601       }
1602     }
1603     return changed;
1604   }
1605 };
1606 
1607 // Inlined accessors for Compile::node_nodes that require the preceding class:
1608 inline Node_Notes*
1609 Compile::locate_node_notes(GrowableArray<Node_Notes*>* arr,
1610                            int idx, bool can_grow) {
1611   assert(idx >= 0, "oob");
1612   int block_idx = (idx >> _log2_node_notes_block_size);
1613   int grow_by = (block_idx - (arr == NULL? 0: arr->length()));
1614   if (grow_by >= 0) {
1615     if (!can_grow)  return NULL;
1616     grow_node_notes(arr, grow_by + 1);
1617   }
1618   // (Every element of arr is a sub-array of length _node_notes_block_size.)
1619   return arr->at(block_idx) + (idx & (_node_notes_block_size-1));
1620 }
1621 
1622 inline bool
1623 Compile::set_node_notes_at(int idx, Node_Notes* value) {
1624   if (value == NULL || value->is_clear())
1625     return false;  // nothing to write => write nothing
1626   Node_Notes* loc = locate_node_notes(_node_note_array, idx, true);
1627   assert(loc != NULL, "");
1628   return loc->update_from(value);
1629 }
1630 
1631 
1632 //------------------------------TypeNode---------------------------------------
1633 // Node with a Type constant.
1634 class TypeNode : public Node {
1635 protected:
1636   virtual uint hash() const;    // Check the type
1637   virtual uint cmp( const Node &n ) const;
1638   virtual uint size_of() const; // Size is bigger
1639   const Type* const _type;
1640 public:
1641   void set_type(const Type* t) {
1642     assert(t != NULL, "sanity");
1643     debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
1644     *(const Type**)&_type = t;   // cast away const-ness
1645     // If this node is in the hash table, make sure it doesn't need a rehash.
1646     assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
1647   }
1648   const Type* type() const { assert(_type != NULL, "sanity"); return _type; };
1649   TypeNode( const Type *t, uint required ) : Node(required), _type(t) {
1650     init_class_id(Class_Type);
1651   }
1652   virtual const Type *Value( PhaseTransform *phase ) const;
1653   virtual const Type *bottom_type() const;
1654   virtual       uint  ideal_reg() const;
1655 #ifndef PRODUCT
1656   virtual void dump_spec(outputStream *st) const;
1657 #endif
1658 };
1659 
1660 #endif // SHARE_VM_OPTO_NODE_HPP
--- EOF ---