1 /*
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   3  * Copyright (c) 2024, 2025, Alibaba Group Holding Limited. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
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  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
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  25 
  26 #ifndef SHARE_OPTO_NODE_HPP
  27 #define SHARE_OPTO_NODE_HPP
  28 
  29 #include "libadt/vectset.hpp"
  30 #include "opto/compile.hpp"
  31 #include "opto/type.hpp"
  32 #include "utilities/copy.hpp"
  33 
  34 // Portions of code courtesy of Clifford Click
  35 
  36 // Optimization - Graph Style
  37 
  38 
  39 class AbstractLockNode;
  40 class AddNode;
  41 class AddPNode;
  42 class AliasInfo;
  43 class AllocateArrayNode;
  44 class AllocateNode;
  45 class ArrayCopyNode;
  46 class BaseCountedLoopNode;
  47 class BaseCountedLoopEndNode;
  48 class BlackholeNode;
  49 class Block;
  50 class BoolNode;
  51 class BoxLockNode;
  52 class CMoveNode;
  53 class CallDynamicJavaNode;
  54 class CallJavaNode;
  55 class CallLeafNode;
  56 class CallLeafNoFPNode;
  57 class CallLeafPureNode;
  58 class CallNode;
  59 class CallRuntimeNode;
  60 class CallStaticJavaNode;
  61 class CastFFNode;
  62 class CastHHNode;
  63 class CastDDNode;
  64 class CastVVNode;
  65 class CastIINode;
  66 class CastLLNode;
  67 class CastPPNode;
  68 class CatchNode;
  69 class CatchProjNode;
  70 class CheckCastPPNode;
  71 class ClearArrayNode;
  72 class CmpNode;
  73 class CodeBuffer;
  74 class ConstraintCastNode;
  75 class ConNode;
  76 class ConINode;
  77 class ConvertNode;
  78 class CompareAndSwapNode;
  79 class CompareAndExchangeNode;
  80 class CountedLoopNode;
  81 class CountedLoopEndNode;
  82 class DecodeNarrowPtrNode;
  83 class DecodeNNode;
  84 class DecodeNKlassNode;
  85 class EncodeNarrowPtrNode;
  86 class EncodePNode;
  87 class EncodePKlassNode;
  88 class FastLockNode;
  89 class FastUnlockNode;
  90 class FlatArrayCheckNode;
  91 class HaltNode;
  92 class IfNode;
  93 class IfProjNode;
  94 class IfFalseNode;
  95 class IfTrueNode;
  96 class InitializeNode;
  97 class JVMState;
  98 class JumpNode;
  99 class JumpProjNode;
 100 class LoadNode;
 101 class LoadStoreNode;
 102 class LoadStoreConditionalNode;
 103 class LockNode;
 104 class LongCountedLoopNode;
 105 class LongCountedLoopEndNode;
 106 class LoopNode;
 107 class LShiftNode;
 108 class MachBranchNode;
 109 class MachCallDynamicJavaNode;
 110 class MachCallJavaNode;
 111 class MachCallLeafNode;
 112 class MachCallNode;
 113 class MachCallRuntimeNode;
 114 class MachCallStaticJavaNode;
 115 class MachConstantBaseNode;
 116 class MachConstantNode;
 117 class MachGotoNode;
 118 class MachIfNode;
 119 class MachJumpNode;
 120 class MachNode;
 121 class MachNullCheckNode;
 122 class MachProjNode;
 123 class MachPrologNode;
 124 class MachReturnNode;
 125 class MachSafePointNode;
 126 class MachSpillCopyNode;
 127 class MachTempNode;
 128 class MachMergeNode;
 129 class MachMemBarNode;
 130 class MachVEPNode;
 131 class Matcher;
 132 class MemBarNode;
 133 class MemBarStoreStoreNode;
 134 class MemNode;
 135 class MergeMemNode;
 136 class MinMaxNode;
 137 class MoveNode;
 138 class MulNode;
 139 class MultiNode;
 140 class MultiBranchNode;
 141 class NarrowMemProjNode;
 142 class NegNode;
 143 class NegVNode;
 144 class NeverBranchNode;
 145 class Opaque1Node;
 146 class OpaqueLoopInitNode;
 147 class OpaqueLoopStrideNode;
 148 class OpaqueMultiversioningNode;
 149 class OpaqueNotNullNode;
 150 class OpaqueInitializedAssertionPredicateNode;
 151 class OpaqueTemplateAssertionPredicateNode;
 152 class OuterStripMinedLoopNode;
 153 class OuterStripMinedLoopEndNode;
 154 class Node;
 155 class Node_Array;
 156 class Node_List;
 157 class Node_Stack;
 158 class OopMap;
 159 class ParmNode;
 160 class ParsePredicateNode;
 161 class PCTableNode;
 162 class PhaseCCP;
 163 class PhaseGVN;
 164 class PhaseIdealLoop;
 165 class PhaseIterGVN;
 166 class PhaseRegAlloc;
 167 class PhaseTransform;
 168 class PhaseValues;
 169 class PhiNode;
 170 class Pipeline;
 171 class PopulateIndexNode;
 172 class ProjNode;
 173 class RangeCheckNode;
 174 class ReductionNode;
 175 class RegMask;
 176 class RegionNode;
 177 class RootNode;
 178 class SafePointNode;
 179 class SafePointScalarObjectNode;
 180 class SafePointScalarMergeNode;
 181 class SaturatingVectorNode;
 182 class StartNode;
 183 class State;
 184 class StoreNode;
 185 class SubNode;
 186 class SubTypeCheckNode;
 187 class Type;
 188 class TypeNode;
 189 class UnlockNode;
 190 class InlineTypeNode;
 191 class LoadFlatNode;
 192 class StoreFlatNode;
 193 class VectorNode;
 194 class LoadVectorNode;
 195 class LoadVectorMaskedNode;
 196 class StoreVectorMaskedNode;
 197 class LoadVectorGatherNode;
 198 class LoadVectorGatherMaskedNode;
 199 class StoreVectorNode;
 200 class StoreVectorScatterNode;
 201 class StoreVectorScatterMaskedNode;
 202 class VerifyVectorAlignmentNode;
 203 class VectorMaskCmpNode;
 204 class VectorUnboxNode;
 205 class VectorSet;
 206 class VectorReinterpretNode;
 207 class ShiftVNode;
 208 class MulVLNode;
 209 class ExpandVNode;
 210 class CompressVNode;
 211 class CompressMNode;
 212 class C2_MacroAssembler;
 213 
 214 
 215 #ifndef OPTO_DU_ITERATOR_ASSERT
 216 #ifdef ASSERT
 217 #define OPTO_DU_ITERATOR_ASSERT 1
 218 #else
 219 #define OPTO_DU_ITERATOR_ASSERT 0
 220 #endif
 221 #endif //OPTO_DU_ITERATOR_ASSERT
 222 
 223 #if OPTO_DU_ITERATOR_ASSERT
 224 class DUIterator;
 225 class DUIterator_Fast;
 226 class DUIterator_Last;
 227 #else
 228 typedef uint   DUIterator;
 229 typedef Node** DUIterator_Fast;
 230 typedef Node** DUIterator_Last;
 231 #endif
 232 
 233 typedef ResizeableHashTable<Node*, Node*, AnyObj::RESOURCE_AREA, mtCompiler> OrigToNewHashtable;
 234 
 235 // Node Sentinel
 236 #define NodeSentinel (Node*)-1
 237 
 238 // Unknown count frequency
 239 #define COUNT_UNKNOWN (-1.0f)
 240 
 241 //------------------------------Node-------------------------------------------
 242 // Nodes define actions in the program.  They create values, which have types.
 243 // They are both vertices in a directed graph and program primitives.  Nodes
 244 // are labeled; the label is the "opcode", the primitive function in the lambda
 245 // calculus sense that gives meaning to the Node.  Node inputs are ordered (so
 246 // that "a-b" is different from "b-a").  The inputs to a Node are the inputs to
 247 // the Node's function.  These inputs also define a Type equation for the Node.
 248 // Solving these Type equations amounts to doing dataflow analysis.
 249 // Control and data are uniformly represented in the graph.  Finally, Nodes
 250 // have a unique dense integer index which is used to index into side arrays
 251 // whenever I have phase-specific information.
 252 
 253 class Node {
 254 
 255   // Lots of restrictions on cloning Nodes
 256   NONCOPYABLE(Node);
 257 
 258 public:
 259   friend class Compile;
 260   #if OPTO_DU_ITERATOR_ASSERT
 261   friend class DUIterator_Common;
 262   friend class DUIterator;
 263   friend class DUIterator_Fast;
 264   friend class DUIterator_Last;
 265   #endif
 266 
 267   // Because Nodes come and go, I define an Arena of Node structures to pull
 268   // from.  This should allow fast access to node creation & deletion.  This
 269   // field is a local cache of a value defined in some "program fragment" for
 270   // which these Nodes are just a part of.
 271 
 272   inline void* operator new(size_t x) throw() {
 273     Compile* C = Compile::current();
 274     Node* n = (Node*)C->node_arena()->AmallocWords(x);
 275     return (void*)n;
 276   }
 277 
 278   // Delete is a NOP
 279   void operator delete( void *ptr ) {}
 280   // Fancy destructor; eagerly attempt to reclaim Node numberings and storage
 281   void destruct(PhaseValues* phase);
 282 
 283   // Create a new Node.  Required is the number is of inputs required for
 284   // semantic correctness.
 285   Node( uint required );
 286 
 287   // Create a new Node with given input edges.
 288   // This version requires use of the "edge-count" new.
 289   // E.g.  new (C,3) FooNode( C, nullptr, left, right );
 290   Node( Node *n0 );
 291   Node( Node *n0, Node *n1 );
 292   Node( Node *n0, Node *n1, Node *n2 );
 293   Node( Node *n0, Node *n1, Node *n2, Node *n3 );
 294   Node( Node *n0, Node *n1, Node *n2, Node *n3, Node *n4 );
 295   Node( Node *n0, Node *n1, Node *n2, Node *n3, Node *n4, Node *n5 );
 296   Node( Node *n0, Node *n1, Node *n2, Node *n3,
 297             Node *n4, Node *n5, Node *n6 );
 298 
 299   // Clone an inherited Node given only the base Node type.
 300   Node* clone() const;
 301 
 302   // Clone a Node, immediately supplying one or two new edges.
 303   // The first and second arguments, if non-null, replace in(1) and in(2),
 304   // respectively.
 305   Node* clone_with_data_edge(Node* in1, Node* in2 = nullptr) const {
 306     Node* nn = clone();
 307     if (in1 != nullptr)  nn->set_req(1, in1);
 308     if (in2 != nullptr)  nn->set_req(2, in2);
 309     return nn;
 310   }
 311 
 312 private:
 313   // Shared setup for the above constructors.
 314   // Handles all interactions with Compile::current.
 315   // Puts initial values in all Node fields except _idx.
 316   // Returns the initial value for _idx, which cannot
 317   // be initialized by assignment.
 318   inline int Init(int req);
 319 
 320 //----------------- input edge handling
 321 protected:
 322   friend class PhaseCFG;        // Access to address of _in array elements
 323   Node **_in;                   // Array of use-def references to Nodes
 324   Node **_out;                  // Array of def-use references to Nodes
 325 
 326   // Input edges are split into two categories.  Required edges are required
 327   // for semantic correctness; order is important and nulls are allowed.
 328   // Precedence edges are used to help determine execution order and are
 329   // added, e.g., for scheduling purposes.  They are unordered and not
 330   // duplicated; they have no embedded nulls.  Edges from 0 to _cnt-1
 331   // are required, from _cnt to _max-1 are precedence edges.
 332   node_idx_t _cnt;              // Total number of required Node inputs.
 333 
 334   node_idx_t _max;              // Actual length of input array.
 335 
 336   // Output edges are an unordered list of def-use edges which exactly
 337   // correspond to required input edges which point from other nodes
 338   // to this one.  Thus the count of the output edges is the number of
 339   // users of this node.
 340   node_idx_t _outcnt;           // Total number of Node outputs.
 341 
 342   node_idx_t _outmax;           // Actual length of output array.
 343 
 344   // Grow the actual input array to the next larger power-of-2 bigger than len.
 345   void grow( uint len );
 346   // Grow the output array to the next larger power-of-2 bigger than len.
 347   void out_grow( uint len );
 348   // Resize input or output array to grow it to the next larger power-of-2
 349   // bigger than len.
 350   void resize_array(Node**& array, node_idx_t& max_size, uint len, bool needs_clearing);
 351 
 352 public:
 353   // Each Node is assigned a unique small/dense number. This number is used
 354   // to index into auxiliary arrays of data and bit vectors.
 355   // The value of _idx can be changed using the set_idx() method.
 356   //
 357   // The PhaseRenumberLive phase renumbers nodes based on liveness information.
 358   // Therefore, it updates the value of the _idx field. The parse-time _idx is
 359   // preserved in _parse_idx.
 360   node_idx_t _idx;
 361   DEBUG_ONLY(const node_idx_t _parse_idx;)
 362   // IGV node identifier. Two nodes, possibly in different compilation phases,
 363   // have the same IGV identifier if (and only if) they are the very same node
 364   // (same memory address) or one is "derived" from the other (by e.g.
 365   // renumbering or matching). This identifier makes it possible to follow the
 366   // entire lifetime of a node in IGV even if its C2 identifier (_idx) changes.
 367   NOT_PRODUCT(node_idx_t _igv_idx;)
 368 
 369   // Get the (read-only) number of input edges
 370   uint req() const { return _cnt; }
 371   uint len() const { return _max; }
 372   // Get the (read-only) number of output edges
 373   uint outcnt() const { return _outcnt; }
 374 
 375 #if OPTO_DU_ITERATOR_ASSERT
 376   // Iterate over the out-edges of this node.  Deletions are illegal.
 377   inline DUIterator outs() const;
 378   // Use this when the out array might have changed to suppress asserts.
 379   inline DUIterator& refresh_out_pos(DUIterator& i) const;
 380   // Does the node have an out at this position?  (Used for iteration.)
 381   inline bool has_out(DUIterator& i) const;
 382   inline Node*    out(DUIterator& i) const;
 383   // Iterate over the out-edges of this node.  All changes are illegal.
 384   inline DUIterator_Fast fast_outs(DUIterator_Fast& max) const;
 385   inline Node*    fast_out(DUIterator_Fast& i) const;
 386   // Iterate over the out-edges of this node, deleting one at a time.
 387   inline DUIterator_Last last_outs(DUIterator_Last& min) const;
 388   inline Node*    last_out(DUIterator_Last& i) const;
 389   // The inline bodies of all these methods are after the iterator definitions.
 390 #else
 391   // Iterate over the out-edges of this node.  Deletions are illegal.
 392   // This iteration uses integral indexes, to decouple from array reallocations.
 393   DUIterator outs() const  { return 0; }
 394   // Use this when the out array might have changed to suppress asserts.
 395   DUIterator refresh_out_pos(DUIterator i) const { return i; }
 396 
 397   // Reference to the i'th output Node.  Error if out of bounds.
 398   Node*    out(DUIterator i) const { assert(i < _outcnt, "oob"); return _out[i]; }
 399   // Does the node have an out at this position?  (Used for iteration.)
 400   bool has_out(DUIterator i) const { return i < _outcnt; }
 401 
 402   // Iterate over the out-edges of this node.  All changes are illegal.
 403   // This iteration uses a pointer internal to the out array.
 404   DUIterator_Fast fast_outs(DUIterator_Fast& max) const {
 405     Node** out = _out;
 406     // Assign a limit pointer to the reference argument:
 407     max = out + (ptrdiff_t)_outcnt;
 408     // Return the base pointer:
 409     return out;
 410   }
 411   Node*    fast_out(DUIterator_Fast i) const  { return *i; }
 412   // Iterate over the out-edges of this node, deleting one at a time.
 413   // This iteration uses a pointer internal to the out array.
 414   DUIterator_Last last_outs(DUIterator_Last& min) const {
 415     Node** out = _out;
 416     // Assign a limit pointer to the reference argument:
 417     min = out;
 418     // Return the pointer to the start of the iteration:
 419     return out + (ptrdiff_t)_outcnt - 1;
 420   }
 421   Node*    last_out(DUIterator_Last i) const  { return *i; }
 422 #endif
 423 
 424   // Reference to the i'th input Node.  Error if out of bounds.
 425   Node* in(uint i) const { assert(i < _max, "oob: i=%d, _max=%d", i, _max); return _in[i]; }
 426   // Reference to the i'th input Node.  null if out of bounds.
 427   Node* lookup(uint i) const { return ((i < _max) ? _in[i] : nullptr); }
 428   // Reference to the i'th output Node.  Error if out of bounds.
 429   // Use this accessor sparingly.  We are going trying to use iterators instead.
 430   Node* raw_out(uint i) const { assert(i < _outcnt,"oob"); return _out[i]; }
 431   // Return the unique out edge.
 432   Node* unique_out() const { assert(_outcnt==1,"not unique"); return _out[0]; }
 433 
 434   // In some cases, a node n is only used by a single use, but the use may use
 435   // n once or multiple times:
 436   //   use = ConvF2I(this)
 437   //   use = AddI(this, this)
 438   Node* unique_multiple_edges_out_or_null() const;
 439 
 440   // Delete out edge at position 'i' by moving last out edge to position 'i'
 441   void  raw_del_out(uint i) {
 442     assert(i < _outcnt,"oob");
 443     assert(_outcnt > 0,"oob");
 444     #if OPTO_DU_ITERATOR_ASSERT
 445     // Record that a change happened here.
 446     DEBUG_ONLY(_last_del = _out[i]; ++_del_tick);
 447     #endif
 448     _out[i] = _out[--_outcnt];
 449     // Smash the old edge so it can't be used accidentally.
 450     DEBUG_ONLY(_out[_outcnt] = (Node *)(uintptr_t)0xdeadbeef);
 451   }
 452 
 453 #ifdef ASSERT
 454   bool is_dead() const;
 455   static bool is_not_dead(const Node* n);
 456   bool is_reachable_from_root() const;
 457 #endif
 458   // Check whether node has become unreachable
 459   bool is_unreachable(PhaseIterGVN &igvn) const;
 460 
 461   // Set a required input edge, also updates corresponding output edge
 462   void add_req( Node *n ); // Append a NEW required input
 463   void add_req( Node *n0, Node *n1 ) {
 464     add_req(n0); add_req(n1); }
 465   void add_req( Node *n0, Node *n1, Node *n2 ) {
 466     add_req(n0); add_req(n1); add_req(n2); }
 467   void add_req_batch( Node* n, uint m ); // Append m NEW required inputs (all n).
 468   void del_req( uint idx ); // Delete required edge & compact
 469   void del_req_ordered( uint idx ); // Delete required edge & compact with preserved order
 470   void ins_req( uint i, Node *n ); // Insert a NEW required input
 471   void set_req( uint i, Node *n ) {
 472     assert( is_not_dead(n), "can not use dead node");
 473     assert( i < _cnt, "oob: i=%d, _cnt=%d", i, _cnt);
 474     assert( !VerifyHashTableKeys || _hash_lock == 0,
 475             "remove node from hash table before modifying it");
 476     Node** p = &_in[i];    // cache this._in, across the del_out call
 477     if (*p != nullptr)  (*p)->del_out((Node *)this);
 478     (*p) = n;
 479     if (n != nullptr)      n->add_out((Node *)this);
 480     Compile::current()->record_modified_node(this);
 481   }
 482   // Light version of set_req() to init inputs after node creation.
 483   void init_req( uint i, Node *n ) {
 484     assert( (i == 0 && this == n) ||
 485             is_not_dead(n), "can not use dead node");
 486     assert( i < _cnt, "oob");
 487     assert( !VerifyHashTableKeys || _hash_lock == 0,
 488             "remove node from hash table before modifying it");
 489     assert( _in[i] == nullptr, "sanity");
 490     _in[i] = n;
 491     if (n != nullptr)      n->add_out((Node *)this);
 492     Compile::current()->record_modified_node(this);
 493   }
 494   // Find first occurrence of n among my edges:
 495   int find_edge(Node* n);
 496   int find_prec_edge(Node* n) {
 497     for (uint i = req(); i < len(); i++) {
 498       if (_in[i] == n) return i;
 499       if (_in[i] == nullptr) {
 500         DEBUG_ONLY( while ((++i) < len()) assert(_in[i] == nullptr, "Gap in prec edges!"); )
 501         break;
 502       }
 503     }
 504     return -1;
 505   }
 506   int replace_edge(Node* old, Node* neww, PhaseGVN* gvn = nullptr);
 507   int replace_edges_in_range(Node* old, Node* neww, int start, int end, PhaseGVN* gvn);
 508   // null out all inputs to eliminate incoming Def-Use edges.
 509   void disconnect_inputs(Compile* C);
 510 
 511   // Quickly, return true if and only if I am Compile::current()->top().
 512   bool is_top() const {
 513     assert((this == (Node*) Compile::current()->top()) == (_out == nullptr), "");
 514     return (_out == nullptr);
 515   }
 516   // Reaffirm invariants for is_top.  (Only from Compile::set_cached_top_node.)
 517   void setup_is_top();
 518 
 519   // Strip away casting.  (It is depth-limited.)
 520   Node* uncast(bool keep_deps = false) const;
 521   // Return whether two Nodes are equivalent, after stripping casting.
 522   bool eqv_uncast(const Node* n, bool keep_deps = false) const {
 523     return (this->uncast(keep_deps) == n->uncast(keep_deps));
 524   }
 525 
 526   // Find out of current node that matches opcode.
 527   Node* find_out_with(int opcode);
 528   // Return true if the current node has an out that matches opcode.
 529   bool has_out_with(int opcode);
 530   // Return true if the current node has an out that matches any of the opcodes.
 531   bool has_out_with(int opcode1, int opcode2, int opcode3, int opcode4);
 532 
 533 private:
 534   static Node* uncast_helper(const Node* n, bool keep_deps);
 535 
 536   // Add an output edge to the end of the list
 537   void add_out( Node *n ) {
 538     if (is_top())  return;
 539     if( _outcnt == _outmax ) out_grow(_outcnt);
 540     _out[_outcnt++] = n;
 541   }
 542   // Delete an output edge
 543   void del_out( Node *n ) {
 544     if (is_top())  return;
 545     Node** outp = &_out[_outcnt];
 546     // Find and remove n
 547     do {
 548       assert(outp > _out, "Missing Def-Use edge");
 549     } while (*--outp != n);
 550     *outp = _out[--_outcnt];
 551     // Smash the old edge so it can't be used accidentally.
 552     DEBUG_ONLY(_out[_outcnt] = (Node *)(uintptr_t)0xdeadbeef);
 553     // Record that a change happened here.
 554     #if OPTO_DU_ITERATOR_ASSERT
 555     DEBUG_ONLY(_last_del = n; ++_del_tick);
 556     #endif
 557   }
 558   // Close gap after removing edge.
 559   void close_prec_gap_at(uint gap) {
 560     assert(_cnt <= gap && gap < _max, "no valid prec edge");
 561     uint i = gap;
 562     Node *last = nullptr;
 563     for (; i < _max-1; ++i) {
 564       Node *next = _in[i+1];
 565       if (next == nullptr) break;
 566       last = next;
 567     }
 568     _in[gap] = last;  // Move last slot to empty one.
 569     _in[i] = nullptr; // null out last slot.
 570   }
 571 
 572 public:
 573   // Globally replace this node by a given new node, updating all uses.
 574   void replace_by(Node* new_node);
 575   // Globally replace this node by a given new node, updating all uses
 576   // and cutting input edges of old node.
 577   void subsume_by(Node* new_node, Compile* c) {
 578     replace_by(new_node);
 579     disconnect_inputs(c);
 580   }
 581   void set_req_X(uint i, Node *n, PhaseIterGVN *igvn);
 582   void set_req_X(uint i, Node *n, PhaseGVN *gvn);
 583   // Find the one non-null required input.  RegionNode only
 584   Node *nonnull_req() const;
 585   // Add or remove precedence edges
 586   void add_prec( Node *n );
 587   void rm_prec( uint i );
 588 
 589   // Note: prec(i) will not necessarily point to n if edge already exists.
 590   void set_prec( uint i, Node *n ) {
 591     assert(i < _max, "oob: i=%d, _max=%d", i, _max);
 592     assert(is_not_dead(n), "can not use dead node");
 593     assert(i >= _cnt, "not a precedence edge");
 594     // Avoid spec violation: duplicated prec edge.
 595     if (_in[i] == n) return;
 596     if (n == nullptr || find_prec_edge(n) != -1) {
 597       rm_prec(i);
 598       return;
 599     }
 600     if (_in[i] != nullptr) _in[i]->del_out((Node *)this);
 601     _in[i] = n;
 602     n->add_out((Node *)this);
 603     Compile::current()->record_modified_node(this);
 604   }
 605 
 606   // Set this node's index, used by cisc_version to replace current node
 607   void set_idx(uint new_idx) {
 608     _idx = new_idx;
 609   }
 610   // Swap input edge order.  (Edge indexes i1 and i2 are usually 1 and 2.)
 611   void swap_edges(uint i1, uint i2) {
 612     DEBUG_ONLY(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
 613     // Def-Use info is unchanged
 614     Node* n1 = in(i1);
 615     Node* n2 = in(i2);
 616     _in[i1] = n2;
 617     _in[i2] = n1;
 618     // If this node is in the hash table, make sure it doesn't need a rehash.
 619     assert(check_hash == NO_HASH || check_hash == hash(), "edge swap must preserve hash code");
 620     // Flip swapped edges flag.
 621     if (has_swapped_edges()) {
 622       remove_flag(Node::Flag_has_swapped_edges);
 623     } else {
 624       add_flag(Node::Flag_has_swapped_edges);
 625     }
 626   }
 627 
 628   // Iterators over input Nodes for a Node X are written as:
 629   // for( i = 0; i < X.req(); i++ ) ... X[i] ...
 630   // NOTE: Required edges can contain embedded null pointers.
 631 
 632 //----------------- Other Node Properties
 633 
 634   // Generate class IDs for (some) ideal nodes so that it is possible to determine
 635   // the type of a node using a non-virtual method call (the method is_<Node>() below).
 636   //
 637   // A class ID of an ideal node is a set of bits. In a class ID, a single bit determines
 638   // the type of the node the ID represents; another subset of an ID's bits are reserved
 639   // for the superclasses of the node represented by the ID.
 640   //
 641   // By design, if A is a supertype of B, A.is_B() returns true and B.is_A()
 642   // returns false. A.is_A() returns true.
 643   //
 644   // If two classes, A and B, have the same superclass, a different bit of A's class id
 645   // is reserved for A's type than for B's type. That bit is specified by the third
 646   // parameter in the macro DEFINE_CLASS_ID.
 647   //
 648   // By convention, classes with deeper hierarchy are declared first. Moreover,
 649   // classes with the same hierarchy depth are sorted by usage frequency.
 650   //
 651   // The query method masks the bits to cut off bits of subclasses and then compares
 652   // the result with the class id (see the macro DEFINE_CLASS_QUERY below).
 653   //
 654   //  Class_MachCall=30, ClassMask_MachCall=31
 655   // 12               8               4               0
 656   //  0   0   0   0   0   0   0   0   1   1   1   1   0
 657   //                                  |   |   |   |
 658   //                                  |   |   |   Bit_Mach=2
 659   //                                  |   |   Bit_MachReturn=4
 660   //                                  |   Bit_MachSafePoint=8
 661   //                                  Bit_MachCall=16
 662   //
 663   //  Class_CountedLoop=56, ClassMask_CountedLoop=63
 664   // 12               8               4               0
 665   //  0   0   0   0   0   0   0   1   1   1   0   0   0
 666   //                              |   |   |
 667   //                              |   |   Bit_Region=8
 668   //                              |   Bit_Loop=16
 669   //                              Bit_CountedLoop=32
 670 
 671   #define DEFINE_CLASS_ID(cl, supcl, subn) \
 672   Bit_##cl = (Class_##supcl == 0) ? 1 << subn : (Bit_##supcl) << (1 + subn) , \
 673   Class_##cl = Class_##supcl + Bit_##cl , \
 674   ClassMask_##cl = ((Bit_##cl << 1) - 1) ,
 675 
 676   // This enum is used only for C2 ideal and mach nodes with is_<node>() methods
 677   // so that its values fit into 32 bits.
 678   enum NodeClasses {
 679     Bit_Node   = 0x00000000,
 680     Class_Node = 0x00000000,
 681     ClassMask_Node = 0xFFFFFFFF,
 682 
 683     DEFINE_CLASS_ID(Multi, Node, 0)
 684       DEFINE_CLASS_ID(SafePoint, Multi, 0)
 685         DEFINE_CLASS_ID(Call,      SafePoint, 0)
 686           DEFINE_CLASS_ID(CallJava,         Call, 0)
 687             DEFINE_CLASS_ID(CallStaticJava,   CallJava, 0)
 688             DEFINE_CLASS_ID(CallDynamicJava,  CallJava, 1)
 689           DEFINE_CLASS_ID(CallRuntime,      Call, 1)
 690             DEFINE_CLASS_ID(CallLeaf,         CallRuntime, 0)
 691               DEFINE_CLASS_ID(CallLeafNoFP,     CallLeaf, 0)
 692               DEFINE_CLASS_ID(CallLeafPure,     CallLeaf, 1)
 693           DEFINE_CLASS_ID(Allocate,         Call, 2)
 694             DEFINE_CLASS_ID(AllocateArray,    Allocate, 0)
 695           DEFINE_CLASS_ID(AbstractLock,     Call, 3)
 696             DEFINE_CLASS_ID(Lock,             AbstractLock, 0)
 697             DEFINE_CLASS_ID(Unlock,           AbstractLock, 1)
 698           DEFINE_CLASS_ID(ArrayCopy,        Call, 4)
 699         DEFINE_CLASS_ID(LoadFlat,  SafePoint, 1)
 700         DEFINE_CLASS_ID(StoreFlat, SafePoint, 2)
 701       DEFINE_CLASS_ID(MultiBranch, Multi, 1)
 702         DEFINE_CLASS_ID(PCTable,     MultiBranch, 0)
 703           DEFINE_CLASS_ID(Catch,       PCTable, 0)
 704           DEFINE_CLASS_ID(Jump,        PCTable, 1)
 705         DEFINE_CLASS_ID(If,          MultiBranch, 1)
 706           DEFINE_CLASS_ID(BaseCountedLoopEnd,     If, 0)
 707             DEFINE_CLASS_ID(CountedLoopEnd,       BaseCountedLoopEnd, 0)
 708             DEFINE_CLASS_ID(LongCountedLoopEnd,   BaseCountedLoopEnd, 1)
 709           DEFINE_CLASS_ID(RangeCheck,             If, 1)
 710           DEFINE_CLASS_ID(OuterStripMinedLoopEnd, If, 2)
 711           DEFINE_CLASS_ID(ParsePredicate,         If, 3)
 712         DEFINE_CLASS_ID(NeverBranch, MultiBranch, 2)
 713       DEFINE_CLASS_ID(Start,       Multi, 2)
 714       DEFINE_CLASS_ID(MemBar,      Multi, 3)
 715         DEFINE_CLASS_ID(Initialize,       MemBar, 0)
 716         DEFINE_CLASS_ID(MemBarStoreStore, MemBar, 1)
 717         DEFINE_CLASS_ID(Blackhole,        MemBar, 2)
 718 
 719     DEFINE_CLASS_ID(Mach,  Node, 1)
 720       DEFINE_CLASS_ID(MachReturn, Mach, 0)
 721         DEFINE_CLASS_ID(MachSafePoint, MachReturn, 0)
 722           DEFINE_CLASS_ID(MachCall, MachSafePoint, 0)
 723             DEFINE_CLASS_ID(MachCallJava,         MachCall, 0)
 724               DEFINE_CLASS_ID(MachCallStaticJava,   MachCallJava, 0)
 725               DEFINE_CLASS_ID(MachCallDynamicJava,  MachCallJava, 1)
 726             DEFINE_CLASS_ID(MachCallRuntime,      MachCall, 1)
 727               DEFINE_CLASS_ID(MachCallLeaf,         MachCallRuntime, 0)
 728       DEFINE_CLASS_ID(MachBranch, Mach, 1)
 729         DEFINE_CLASS_ID(MachIf,         MachBranch, 0)
 730         DEFINE_CLASS_ID(MachGoto,       MachBranch, 1)
 731         DEFINE_CLASS_ID(MachNullCheck,  MachBranch, 2)
 732       DEFINE_CLASS_ID(MachSpillCopy,    Mach, 2)
 733       DEFINE_CLASS_ID(MachTemp,         Mach, 3)
 734       DEFINE_CLASS_ID(MachConstantBase, Mach, 4)
 735       DEFINE_CLASS_ID(MachConstant,     Mach, 5)
 736         DEFINE_CLASS_ID(MachJump,       MachConstant, 0)
 737       DEFINE_CLASS_ID(MachMerge,        Mach, 6)
 738       DEFINE_CLASS_ID(MachMemBar,       Mach, 7)
 739       DEFINE_CLASS_ID(MachProlog,       Mach, 8)
 740       DEFINE_CLASS_ID(MachVEP,          Mach, 9)
 741 
 742     DEFINE_CLASS_ID(Type,  Node, 2)
 743       DEFINE_CLASS_ID(Phi,   Type, 0)
 744       DEFINE_CLASS_ID(ConstraintCast, Type, 1)
 745         DEFINE_CLASS_ID(CastII, ConstraintCast, 0)
 746         DEFINE_CLASS_ID(CheckCastPP, ConstraintCast, 1)
 747         DEFINE_CLASS_ID(CastLL, ConstraintCast, 2)
 748         DEFINE_CLASS_ID(CastFF, ConstraintCast, 3)
 749         DEFINE_CLASS_ID(CastDD, ConstraintCast, 4)
 750         DEFINE_CLASS_ID(CastVV, ConstraintCast, 5)
 751         DEFINE_CLASS_ID(CastPP, ConstraintCast, 6)
 752         DEFINE_CLASS_ID(CastHH, ConstraintCast, 7)
 753       DEFINE_CLASS_ID(CMove, Type, 3)
 754       DEFINE_CLASS_ID(SafePointScalarObject, Type, 4)
 755       DEFINE_CLASS_ID(DecodeNarrowPtr, Type, 5)
 756         DEFINE_CLASS_ID(DecodeN, DecodeNarrowPtr, 0)
 757         DEFINE_CLASS_ID(DecodeNKlass, DecodeNarrowPtr, 1)
 758       DEFINE_CLASS_ID(EncodeNarrowPtr, Type, 6)
 759         DEFINE_CLASS_ID(EncodeP, EncodeNarrowPtr, 0)
 760         DEFINE_CLASS_ID(EncodePKlass, EncodeNarrowPtr, 1)
 761       DEFINE_CLASS_ID(Vector, Type, 7)
 762         DEFINE_CLASS_ID(VectorMaskCmp, Vector, 0)
 763         DEFINE_CLASS_ID(VectorUnbox, Vector, 1)
 764         DEFINE_CLASS_ID(VectorReinterpret, Vector, 2)
 765         DEFINE_CLASS_ID(ShiftV, Vector, 3)
 766         DEFINE_CLASS_ID(CompressV, Vector, 4)
 767         DEFINE_CLASS_ID(ExpandV, Vector, 5)
 768         DEFINE_CLASS_ID(CompressM, Vector, 6)
 769         DEFINE_CLASS_ID(Reduction, Vector, 7)
 770         DEFINE_CLASS_ID(NegV, Vector, 8)
 771         DEFINE_CLASS_ID(SaturatingVector, Vector, 9)
 772         DEFINE_CLASS_ID(MulVL, Vector, 10)
 773       DEFINE_CLASS_ID(InlineType, Type, 8)
 774       DEFINE_CLASS_ID(Con, Type, 9)
 775           DEFINE_CLASS_ID(ConI, Con, 0)
 776       DEFINE_CLASS_ID(SafePointScalarMerge, Type, 10)
 777       DEFINE_CLASS_ID(Convert, Type, 11)
 778 
 779 
 780     DEFINE_CLASS_ID(Proj,  Node, 3)
 781       DEFINE_CLASS_ID(CatchProj, Proj, 0)
 782       DEFINE_CLASS_ID(JumpProj,  Proj, 1)
 783       DEFINE_CLASS_ID(IfProj,    Proj, 2)
 784         DEFINE_CLASS_ID(IfTrue,    IfProj, 0)
 785         DEFINE_CLASS_ID(IfFalse,   IfProj, 1)
 786       DEFINE_CLASS_ID(Parm,      Proj, 4)
 787       DEFINE_CLASS_ID(MachProj,  Proj, 5)
 788       DEFINE_CLASS_ID(NarrowMemProj, Proj, 6)
 789 
 790     DEFINE_CLASS_ID(Mem, Node, 4)
 791       DEFINE_CLASS_ID(Load, Mem, 0)
 792         DEFINE_CLASS_ID(LoadVector,  Load, 0)
 793           DEFINE_CLASS_ID(LoadVectorGather, LoadVector, 0)
 794           DEFINE_CLASS_ID(LoadVectorGatherMasked, LoadVector, 1)
 795           DEFINE_CLASS_ID(LoadVectorMasked, LoadVector, 2)
 796       DEFINE_CLASS_ID(Store, Mem, 1)
 797         DEFINE_CLASS_ID(StoreVector, Store, 0)
 798           DEFINE_CLASS_ID(StoreVectorScatter, StoreVector, 0)
 799           DEFINE_CLASS_ID(StoreVectorScatterMasked, StoreVector, 1)
 800           DEFINE_CLASS_ID(StoreVectorMasked, StoreVector, 2)
 801       DEFINE_CLASS_ID(LoadStore, Mem, 2)
 802         DEFINE_CLASS_ID(LoadStoreConditional, LoadStore, 0)
 803           DEFINE_CLASS_ID(CompareAndSwap, LoadStoreConditional, 0)
 804         DEFINE_CLASS_ID(CompareAndExchangeNode, LoadStore, 1)
 805 
 806     DEFINE_CLASS_ID(Region, Node, 5)
 807       DEFINE_CLASS_ID(Loop, Region, 0)
 808         DEFINE_CLASS_ID(Root,                Loop, 0)
 809         DEFINE_CLASS_ID(BaseCountedLoop,     Loop, 1)
 810           DEFINE_CLASS_ID(CountedLoop,       BaseCountedLoop, 0)
 811           DEFINE_CLASS_ID(LongCountedLoop,   BaseCountedLoop, 1)
 812         DEFINE_CLASS_ID(OuterStripMinedLoop, Loop, 2)
 813 
 814     DEFINE_CLASS_ID(Sub,   Node, 6)
 815       DEFINE_CLASS_ID(Cmp,   Sub, 0)
 816         DEFINE_CLASS_ID(FastLock,       Cmp, 0)
 817         DEFINE_CLASS_ID(FastUnlock,     Cmp, 1)
 818         DEFINE_CLASS_ID(SubTypeCheck,   Cmp, 2)
 819         DEFINE_CLASS_ID(FlatArrayCheck, Cmp, 3)
 820 
 821     DEFINE_CLASS_ID(MergeMem, Node, 7)
 822     DEFINE_CLASS_ID(Bool,     Node, 8)
 823     DEFINE_CLASS_ID(AddP,     Node, 9)
 824     DEFINE_CLASS_ID(BoxLock,  Node, 10)
 825     DEFINE_CLASS_ID(Add,      Node, 11)
 826       DEFINE_CLASS_ID(MinMax,      Add, 0)
 827     DEFINE_CLASS_ID(Mul,      Node, 12)
 828     DEFINE_CLASS_ID(ClearArray, Node, 14)
 829     DEFINE_CLASS_ID(Halt,     Node, 15)
 830     DEFINE_CLASS_ID(Opaque1,  Node, 16)
 831       DEFINE_CLASS_ID(OpaqueLoopInit, Opaque1, 0)
 832       DEFINE_CLASS_ID(OpaqueLoopStride, Opaque1, 1)
 833       DEFINE_CLASS_ID(OpaqueMultiversioning, Opaque1, 2)
 834     DEFINE_CLASS_ID(OpaqueNotNull,  Node, 17)
 835     DEFINE_CLASS_ID(OpaqueInitializedAssertionPredicate,  Node, 18)
 836     DEFINE_CLASS_ID(OpaqueTemplateAssertionPredicate,  Node, 19)
 837     DEFINE_CLASS_ID(Move,     Node, 20)
 838     DEFINE_CLASS_ID(LShift,   Node, 21)
 839     DEFINE_CLASS_ID(Neg,      Node, 22)
 840 
 841     _max_classes  = ClassMask_Neg
 842   };
 843   #undef DEFINE_CLASS_ID
 844 
 845   // Flags are sorted by usage frequency.
 846   enum NodeFlags : uint64_t {
 847     Flag_is_Copy                     = 1ULL << 0, // should be first bit to avoid shift
 848     Flag_rematerialize               = 1ULL << 1,
 849     Flag_needs_anti_dependence_check = 1ULL << 2,
 850     Flag_is_macro                    = 1ULL << 3,
 851     Flag_is_Con                      = 1ULL << 4,
 852     Flag_is_cisc_alternate           = 1ULL << 5,
 853     Flag_is_dead_loop_safe           = 1ULL << 6,
 854     Flag_may_be_short_branch         = 1ULL << 7,
 855     Flag_avoid_back_to_back_before   = 1ULL << 8,
 856     Flag_avoid_back_to_back_after    = 1ULL << 9,
 857     Flag_has_call                    = 1ULL << 10,
 858     Flag_has_swapped_edges           = 1ULL << 11,
 859     Flag_is_scheduled                = 1ULL << 12,
 860     Flag_is_expensive                = 1ULL << 13,
 861     Flag_is_predicated_vector        = 1ULL << 14, // Marked on a vector node that has an additional
 862                                                    // mask input controlling the lane operations.
 863     Flag_for_post_loop_opts_igvn     = 1ULL << 15,
 864     Flag_for_merge_stores_igvn       = 1ULL << 16,
 865     Flag_is_removed_by_peephole      = 1ULL << 17,
 866     Flag_is_predicated_using_blend   = 1ULL << 18,
 867     _last_flag                       = Flag_is_predicated_using_blend
 868   };
 869 
 870   class PD;
 871 
 872 private:
 873   juint _class_id;
 874   juint _flags;
 875 
 876 #ifdef ASSERT
 877   static juint max_flags();
 878 #endif
 879 
 880 protected:
 881   // These methods should be called from constructors only.
 882   void init_class_id(juint c) {
 883     _class_id = c; // cast out const
 884   }
 885   void init_flags(uint fl) {
 886     assert(fl <= max_flags(), "invalid node flag");
 887     _flags |= fl;
 888   }
 889   void clear_flag(uint fl) {
 890     assert(fl <= max_flags(), "invalid node flag");
 891     _flags &= ~fl;
 892   }
 893 
 894 public:
 895   juint class_id() const { return _class_id; }
 896 
 897   juint flags() const { return _flags; }
 898 
 899   void add_flag(juint fl) { init_flags(fl); }
 900 
 901   void remove_flag(juint fl) { clear_flag(fl); }
 902 
 903   // Return a dense integer opcode number
 904   virtual int Opcode() const;
 905 
 906   // Virtual inherited Node size
 907   virtual uint size_of() const;
 908 
 909   // Other interesting Node properties
 910   #define DEFINE_CLASS_QUERY(type)                           \
 911   bool is_##type() const {                                   \
 912     return ((_class_id & ClassMask_##type) == Class_##type); \
 913   }                                                          \
 914   type##Node *as_##type() const {                            \
 915     assert(is_##type(), "invalid node class: %s", Name());   \
 916     return (type##Node*)this;                                \
 917   }                                                          \
 918   type##Node* isa_##type() const {                           \
 919     return (is_##type()) ? as_##type() : nullptr;            \
 920   }
 921 
 922   DEFINE_CLASS_QUERY(AbstractLock)
 923   DEFINE_CLASS_QUERY(Add)
 924   DEFINE_CLASS_QUERY(AddP)
 925   DEFINE_CLASS_QUERY(Allocate)
 926   DEFINE_CLASS_QUERY(AllocateArray)
 927   DEFINE_CLASS_QUERY(ArrayCopy)
 928   DEFINE_CLASS_QUERY(BaseCountedLoop)
 929   DEFINE_CLASS_QUERY(BaseCountedLoopEnd)
 930   DEFINE_CLASS_QUERY(Blackhole)
 931   DEFINE_CLASS_QUERY(Bool)
 932   DEFINE_CLASS_QUERY(BoxLock)
 933   DEFINE_CLASS_QUERY(Call)
 934   DEFINE_CLASS_QUERY(CallDynamicJava)
 935   DEFINE_CLASS_QUERY(CallJava)
 936   DEFINE_CLASS_QUERY(CallLeaf)
 937   DEFINE_CLASS_QUERY(CallLeafNoFP)
 938   DEFINE_CLASS_QUERY(CallLeafPure)
 939   DEFINE_CLASS_QUERY(CallRuntime)
 940   DEFINE_CLASS_QUERY(CallStaticJava)
 941   DEFINE_CLASS_QUERY(Catch)
 942   DEFINE_CLASS_QUERY(CatchProj)
 943   DEFINE_CLASS_QUERY(CheckCastPP)
 944   DEFINE_CLASS_QUERY(CastII)
 945   DEFINE_CLASS_QUERY(CastLL)
 946   DEFINE_CLASS_QUERY(CastFF)
 947   DEFINE_CLASS_QUERY(ConI)
 948   DEFINE_CLASS_QUERY(CastPP)
 949   DEFINE_CLASS_QUERY(ConstraintCast)
 950   DEFINE_CLASS_QUERY(ClearArray)
 951   DEFINE_CLASS_QUERY(CMove)
 952   DEFINE_CLASS_QUERY(Cmp)
 953   DEFINE_CLASS_QUERY(Convert)
 954   DEFINE_CLASS_QUERY(CountedLoop)
 955   DEFINE_CLASS_QUERY(CountedLoopEnd)
 956   DEFINE_CLASS_QUERY(DecodeNarrowPtr)
 957   DEFINE_CLASS_QUERY(DecodeN)
 958   DEFINE_CLASS_QUERY(DecodeNKlass)
 959   DEFINE_CLASS_QUERY(EncodeNarrowPtr)
 960   DEFINE_CLASS_QUERY(EncodeP)
 961   DEFINE_CLASS_QUERY(EncodePKlass)
 962   DEFINE_CLASS_QUERY(FastLock)
 963   DEFINE_CLASS_QUERY(FastUnlock)
 964   DEFINE_CLASS_QUERY(FlatArrayCheck)
 965   DEFINE_CLASS_QUERY(Halt)
 966   DEFINE_CLASS_QUERY(If)
 967   DEFINE_CLASS_QUERY(RangeCheck)
 968   DEFINE_CLASS_QUERY(IfProj)
 969   DEFINE_CLASS_QUERY(IfFalse)
 970   DEFINE_CLASS_QUERY(IfTrue)
 971   DEFINE_CLASS_QUERY(Initialize)
 972   DEFINE_CLASS_QUERY(Jump)
 973   DEFINE_CLASS_QUERY(JumpProj)
 974   DEFINE_CLASS_QUERY(LongCountedLoop)
 975   DEFINE_CLASS_QUERY(LongCountedLoopEnd)
 976   DEFINE_CLASS_QUERY(Load)
 977   DEFINE_CLASS_QUERY(LoadStore)
 978   DEFINE_CLASS_QUERY(LoadStoreConditional)
 979   DEFINE_CLASS_QUERY(Lock)
 980   DEFINE_CLASS_QUERY(Loop)
 981   DEFINE_CLASS_QUERY(LShift)
 982   DEFINE_CLASS_QUERY(Mach)
 983   DEFINE_CLASS_QUERY(MachBranch)
 984   DEFINE_CLASS_QUERY(MachCall)
 985   DEFINE_CLASS_QUERY(MachCallDynamicJava)
 986   DEFINE_CLASS_QUERY(MachCallJava)
 987   DEFINE_CLASS_QUERY(MachCallLeaf)
 988   DEFINE_CLASS_QUERY(MachCallRuntime)
 989   DEFINE_CLASS_QUERY(MachCallStaticJava)
 990   DEFINE_CLASS_QUERY(MachConstantBase)
 991   DEFINE_CLASS_QUERY(MachConstant)
 992   DEFINE_CLASS_QUERY(MachGoto)
 993   DEFINE_CLASS_QUERY(MachIf)
 994   DEFINE_CLASS_QUERY(MachJump)
 995   DEFINE_CLASS_QUERY(MachNullCheck)
 996   DEFINE_CLASS_QUERY(MachProj)
 997   DEFINE_CLASS_QUERY(MachProlog)
 998   DEFINE_CLASS_QUERY(MachReturn)
 999   DEFINE_CLASS_QUERY(MachSafePoint)
1000   DEFINE_CLASS_QUERY(MachSpillCopy)
1001   DEFINE_CLASS_QUERY(MachTemp)
1002   DEFINE_CLASS_QUERY(MachMemBar)
1003   DEFINE_CLASS_QUERY(MachMerge)
1004   DEFINE_CLASS_QUERY(MachVEP)
1005   DEFINE_CLASS_QUERY(Mem)
1006   DEFINE_CLASS_QUERY(MemBar)
1007   DEFINE_CLASS_QUERY(MemBarStoreStore)
1008   DEFINE_CLASS_QUERY(MergeMem)
1009   DEFINE_CLASS_QUERY(MinMax)
1010   DEFINE_CLASS_QUERY(Move)
1011   DEFINE_CLASS_QUERY(Mul)
1012   DEFINE_CLASS_QUERY(Multi)
1013   DEFINE_CLASS_QUERY(MultiBranch)
1014   DEFINE_CLASS_QUERY(MulVL)
1015   DEFINE_CLASS_QUERY(NarrowMemProj)
1016   DEFINE_CLASS_QUERY(Neg)
1017   DEFINE_CLASS_QUERY(NegV)
1018   DEFINE_CLASS_QUERY(NeverBranch)
1019   DEFINE_CLASS_QUERY(Opaque1)
1020   DEFINE_CLASS_QUERY(OpaqueNotNull)
1021   DEFINE_CLASS_QUERY(OpaqueInitializedAssertionPredicate)
1022   DEFINE_CLASS_QUERY(OpaqueTemplateAssertionPredicate)
1023   DEFINE_CLASS_QUERY(OpaqueLoopInit)
1024   DEFINE_CLASS_QUERY(OpaqueLoopStride)
1025   DEFINE_CLASS_QUERY(OpaqueMultiversioning)
1026   DEFINE_CLASS_QUERY(OuterStripMinedLoop)
1027   DEFINE_CLASS_QUERY(OuterStripMinedLoopEnd)
1028   DEFINE_CLASS_QUERY(Parm)
1029   DEFINE_CLASS_QUERY(ParsePredicate)
1030   DEFINE_CLASS_QUERY(PCTable)
1031   DEFINE_CLASS_QUERY(Phi)
1032   DEFINE_CLASS_QUERY(Proj)
1033   DEFINE_CLASS_QUERY(Reduction)
1034   DEFINE_CLASS_QUERY(Region)
1035   DEFINE_CLASS_QUERY(Root)
1036   DEFINE_CLASS_QUERY(SafePoint)
1037   DEFINE_CLASS_QUERY(SafePointScalarObject)
1038   DEFINE_CLASS_QUERY(SafePointScalarMerge)
1039   DEFINE_CLASS_QUERY(Start)
1040   DEFINE_CLASS_QUERY(Store)
1041   DEFINE_CLASS_QUERY(Sub)
1042   DEFINE_CLASS_QUERY(SubTypeCheck)
1043   DEFINE_CLASS_QUERY(Type)
1044   DEFINE_CLASS_QUERY(InlineType)
1045   DEFINE_CLASS_QUERY(LoadFlat)
1046   DEFINE_CLASS_QUERY(StoreFlat)
1047   DEFINE_CLASS_QUERY(Vector)
1048   DEFINE_CLASS_QUERY(VectorMaskCmp)
1049   DEFINE_CLASS_QUERY(VectorUnbox)
1050   DEFINE_CLASS_QUERY(VectorReinterpret)
1051   DEFINE_CLASS_QUERY(CompressV)
1052   DEFINE_CLASS_QUERY(ExpandV)
1053   DEFINE_CLASS_QUERY(CompressM)
1054   DEFINE_CLASS_QUERY(LoadVector)
1055   DEFINE_CLASS_QUERY(LoadVectorGather)
1056   DEFINE_CLASS_QUERY(LoadVectorMasked)
1057   DEFINE_CLASS_QUERY(LoadVectorGatherMasked)
1058   DEFINE_CLASS_QUERY(StoreVector)
1059   DEFINE_CLASS_QUERY(StoreVectorScatter)
1060   DEFINE_CLASS_QUERY(StoreVectorMasked)
1061   DEFINE_CLASS_QUERY(StoreVectorScatterMasked)
1062   DEFINE_CLASS_QUERY(SaturatingVector)
1063   DEFINE_CLASS_QUERY(ShiftV)
1064   DEFINE_CLASS_QUERY(Unlock)
1065 
1066   #undef DEFINE_CLASS_QUERY
1067 
1068   // duplicate of is_MachSpillCopy()
1069   bool is_SpillCopy () const {
1070     return ((_class_id & ClassMask_MachSpillCopy) == Class_MachSpillCopy);
1071   }
1072 
1073   bool is_Con () const { return (_flags & Flag_is_Con) != 0; }
1074   // The data node which is safe to leave in dead loop during IGVN optimization.
1075   bool is_dead_loop_safe() const;
1076 
1077   // is_Copy() returns copied edge index (0 or 1)
1078   uint is_Copy() const { return (_flags & Flag_is_Copy); }
1079 
1080   virtual bool is_CFG() const { return false; }
1081 
1082   // If this node is control-dependent on a test, can it be
1083   // rerouted to a dominating equivalent test?  This is usually
1084   // true of non-CFG nodes, but can be false for operations which
1085   // depend for their correct sequencing on more than one test.
1086   // (In that case, hoisting to a dominating test may silently
1087   // skip some other important test.)
1088   virtual bool depends_only_on_test() const { assert(!is_CFG(), ""); return true; };
1089 
1090   // When building basic blocks, I need to have a notion of block beginning
1091   // Nodes, next block selector Nodes (block enders), and next block
1092   // projections.  These calls need to work on their machine equivalents.  The
1093   // Ideal beginning Nodes are RootNode, RegionNode and StartNode.
1094   bool is_block_start() const {
1095     if ( is_Region() )
1096       return this == (const Node*)in(0);
1097     else
1098       return is_Start();
1099   }
1100 
1101   // The Ideal control projection Nodes are IfTrue/IfFalse, JumpProjNode, Root,
1102   // Goto and Return.  This call also returns the block ending Node.
1103   virtual const Node *is_block_proj() const;
1104 
1105   // The node is a "macro" node which needs to be expanded before matching
1106   bool is_macro() const { return (_flags & Flag_is_macro) != 0; }
1107   // The node is expensive: the best control is set during loop opts
1108   bool is_expensive() const { return (_flags & Flag_is_expensive) != 0 && in(0) != nullptr; }
1109   // The node's original edge position is swapped.
1110   bool has_swapped_edges() const { return (_flags & Flag_has_swapped_edges) != 0; }
1111 
1112   bool is_predicated_vector() const { return (_flags & Flag_is_predicated_vector) != 0; }
1113 
1114   bool is_predicated_using_blend() const { return (_flags & Flag_is_predicated_using_blend) != 0; }
1115 
1116   // Used in lcm to mark nodes that have scheduled
1117   bool is_scheduled() const { return (_flags & Flag_is_scheduled) != 0; }
1118 
1119   bool for_post_loop_opts_igvn() const { return (_flags & Flag_for_post_loop_opts_igvn) != 0; }
1120   bool for_merge_stores_igvn() const { return (_flags & Flag_for_merge_stores_igvn) != 0; }
1121 
1122   // Is 'n' possibly a loop entry (i.e. a Parse Predicate projection)?
1123   static bool may_be_loop_entry(Node* n) {
1124     return n != nullptr && n->is_IfProj() && n->in(0)->is_ParsePredicate();
1125   }
1126 
1127 //----------------- Optimization
1128 
1129   // Get the worst-case Type output for this Node.
1130   virtual const class Type *bottom_type() const;
1131 
1132   // If we find a better type for a node, try to record it permanently.
1133   // Return true if this node actually changed.
1134   // Be sure to do the hash_delete game in the "rehash" variant.
1135   void raise_bottom_type(const Type* new_type);
1136 
1137   // Get the address type with which this node uses and/or defs memory,
1138   // or null if none.  The address type is conservatively wide.
1139   // Returns non-null for calls, membars, loads, stores, etc.
1140   // Returns TypePtr::BOTTOM if the node touches memory "broadly".
1141   virtual const class TypePtr *adr_type() const { return nullptr; }
1142 
1143   // Return an existing node which computes the same function as this node.
1144   // The optimistic combined algorithm requires this to return a Node which
1145   // is a small number of steps away (e.g., one of my inputs).
1146   virtual Node* Identity(PhaseGVN* phase);
1147 
1148   // Return the set of values this Node can take on at runtime.
1149   virtual const Type* Value(PhaseGVN* phase) const;
1150 
1151   // Return a node which is more "ideal" than the current node.
1152   // The invariants on this call are subtle.  If in doubt, read the
1153   // treatise in node.cpp above the default implementation AND TEST WITH
1154   // -XX:VerifyIterativeGVN=1
1155   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1156 
1157   // Some nodes have specific Ideal subgraph transformations only if they are
1158   // unique users of specific nodes. Such nodes should be put on IGVN worklist
1159   // for the transformations to happen.
1160   bool has_special_unique_user() const;
1161 
1162   // Skip Proj and CatchProj nodes chains. Check for Null and Top.
1163   Node* find_exact_control(Node* ctrl);
1164 
1165   // Results of the dominance analysis.
1166   enum class DomResult {
1167     NotDominate,         // 'this' node does not dominate 'sub'.
1168     Dominate,            // 'this' node dominates or is equal to 'sub'.
1169     EncounteredDeadCode  // Result is undefined due to encountering dead code.
1170   };
1171   // Check if 'this' node dominates or equal to 'sub'.
1172   DomResult dominates(Node* sub, Node_List &nlist);
1173 
1174   bool remove_dead_region(PhaseGVN *phase, bool can_reshape);
1175 public:
1176 
1177   // See if there is valid pipeline info
1178   static  const Pipeline *pipeline_class();
1179   virtual const Pipeline *pipeline() const;
1180 
1181   // Compute the latency from the def to this instruction of the ith input node
1182   uint latency(uint i);
1183 
1184   // Hash & compare functions, for pessimistic value numbering
1185 
1186   // If the hash function returns the special sentinel value NO_HASH,
1187   // the node is guaranteed never to compare equal to any other node.
1188   // If we accidentally generate a hash with value NO_HASH the node
1189   // won't go into the table and we'll lose a little optimization.
1190   static const uint NO_HASH = 0;
1191   virtual uint hash() const;
1192   virtual bool cmp( const Node &n ) const;
1193 
1194   // Operation appears to be iteratively computed (such as an induction variable)
1195   // It is possible for this operation to return false for a loop-varying
1196   // value, if it appears (by local graph inspection) to be computed by a simple conditional.
1197   bool is_iteratively_computed();
1198 
1199   // Determine if a node is a counted loop induction variable.
1200   // NOTE: The method is defined in "loopnode.cpp".
1201   bool is_cloop_ind_var() const;
1202 
1203   // Return a node with opcode "opc" and same inputs as "this" if one can
1204   // be found; Otherwise return null;
1205   Node* find_similar(int opc);
1206   bool has_same_inputs_as(const Node* other) const;
1207 
1208   // Return the unique control out if only one. Null if none or more than one.
1209   Node* unique_ctrl_out_or_null() const;
1210   // Return the unique control out. Asserts if none or more than one control out.
1211   Node* unique_ctrl_out() const;
1212 
1213   // Set control or add control as precedence edge
1214   void ensure_control_or_add_prec(Node* c);
1215   void add_prec_from(Node* n);
1216 
1217   // Visit boundary uses of the node and apply a callback function for each.
1218   // Recursively traverse uses, stopping and applying the callback when
1219   // reaching a boundary node, defined by is_boundary. Note: the function
1220   // definition appears after the complete type definition of Node_List.
1221   template <typename Callback, typename Check>
1222   void visit_uses(Callback callback, Check is_boundary) const;
1223 
1224   // Returns a clone of the current node that's pinned (if the current node is not) for nodes found in array accesses
1225   // (Load and range check CastII nodes).
1226   // This is used when an array access is made dependent on 2 or more range checks (range check smearing or Loop Predication).
1227   virtual Node* pin_array_access_node() const {
1228     return nullptr;
1229   }
1230 
1231   //----------------- Code Generation
1232 
1233   // Ideal register class for Matching.  Zero means unmatched instruction
1234   // (these are cloned instead of converted to machine nodes).
1235   virtual uint ideal_reg() const;
1236 
1237   static const uint NotAMachineReg;   // must be > max. machine register
1238 
1239   // Do we Match on this edge index or not?  Generally false for Control
1240   // and true for everything else.  Weird for calls & returns.
1241   virtual uint match_edge(uint idx) const;
1242 
1243   // Register class output is returned in
1244   virtual const RegMask &out_RegMask() const;
1245   // Register class input is expected in
1246   virtual const RegMask &in_RegMask(uint) const;
1247   // Should we clone rather than spill this instruction?
1248   bool rematerialize() const;
1249 
1250   // Return JVM State Object if this Node carries debug info, or null otherwise
1251   virtual JVMState* jvms() const;
1252 
1253   // Print as assembly
1254   virtual void format( PhaseRegAlloc *, outputStream* st = tty ) const;
1255   // Emit bytes using C2_MacroAssembler
1256   virtual void emit(C2_MacroAssembler *masm, PhaseRegAlloc *ra_) const;
1257   // Size of instruction in bytes
1258   virtual uint size(PhaseRegAlloc *ra_) const;
1259 
1260   // Convenience function to extract an integer constant from a node.
1261   // If it is not an integer constant (either Con, CastII, or Mach),
1262   // return value_if_unknown.
1263   jint find_int_con(jint value_if_unknown) const {
1264     const TypeInt* t = find_int_type();
1265     return (t != nullptr && t->is_con()) ? t->get_con() : value_if_unknown;
1266   }
1267   // Return the constant, knowing it is an integer constant already
1268   jint get_int() const {
1269     const TypeInt* t = find_int_type();
1270     guarantee(t != nullptr, "must be con");
1271     return t->get_con();
1272   }
1273   // Here's where the work is done.  Can produce non-constant int types too.
1274   const TypeInt* find_int_type() const;
1275   const TypeInteger* find_integer_type(BasicType bt) const;
1276 
1277   // Same thing for long (and intptr_t, via type.hpp):
1278   jlong get_long() const {
1279     const TypeLong* t = find_long_type();
1280     guarantee(t != nullptr, "must be con");
1281     return t->get_con();
1282   }
1283   jlong find_long_con(jint value_if_unknown) const {
1284     const TypeLong* t = find_long_type();
1285     return (t != nullptr && t->is_con()) ? t->get_con() : value_if_unknown;
1286   }
1287   const TypeLong* find_long_type() const;
1288 
1289   jlong get_integer_as_long(BasicType bt) const {
1290     const TypeInteger* t = find_integer_type(bt);
1291     guarantee(t != nullptr && t->is_con(), "must be con");
1292     return t->get_con_as_long(bt);
1293   }
1294   jlong find_integer_as_long(BasicType bt, jlong value_if_unknown) const {
1295     const TypeInteger* t = find_integer_type(bt);
1296     if (t == nullptr || !t->is_con())  return value_if_unknown;
1297     return t->get_con_as_long(bt);
1298   }
1299   const TypePtr* get_ptr_type() const;
1300 
1301   // These guys are called by code generated by ADLC:
1302   intptr_t get_ptr() const;
1303   intptr_t get_narrowcon() const;
1304   jdouble getd() const;
1305   jfloat getf() const;
1306   jshort geth() const;
1307 
1308   // Nodes which are pinned into basic blocks
1309   virtual bool pinned() const { return false; }
1310 
1311   // Nodes which use memory without consuming it, hence need antidependences
1312   // More specifically, needs_anti_dependence_check returns true iff the node
1313   // (a) does a load, and (b) does not perform a store (except perhaps to a
1314   // stack slot or some other unaliased location).
1315   bool needs_anti_dependence_check() const;
1316 
1317   // Return which operand this instruction may cisc-spill. In other words,
1318   // return operand position that can convert from reg to memory access
1319   virtual int cisc_operand() const { return AdlcVMDeps::Not_cisc_spillable; }
1320   bool is_cisc_alternate() const { return (_flags & Flag_is_cisc_alternate) != 0; }
1321 
1322   // Whether this is a memory-writing machine node.
1323   bool is_memory_writer() const { return is_Mach() && bottom_type()->has_memory(); }
1324 
1325   // Whether this is a memory phi node
1326   bool is_memory_phi() const { return is_Phi() && bottom_type() == Type::MEMORY; }
1327 
1328   bool is_div_or_mod(BasicType bt) const;
1329 
1330   bool is_data_proj_of_pure_function(const Node* maybe_pure_function) const;
1331 
1332 //----------------- Printing, etc
1333 #ifndef PRODUCT
1334  public:
1335   Node* find(int idx, bool only_ctrl = false); // Search the graph for the given idx.
1336   Node* find_ctrl(int idx); // Search control ancestors for the given idx.
1337   void dump_bfs(const int max_distance, Node* target, const char* options, outputStream* st, const frame* fr = nullptr) const;
1338   void dump_bfs(const int max_distance, Node* target, const char* options) const; // directly to tty
1339   void dump_bfs(const int max_distance) const; // dump_bfs(max_distance, nullptr, nullptr)
1340   void dump_bfs(const int max_distance, Node* target, const char* options, void* sp, void* fp, void* pc) const;
1341   class DumpConfig {
1342    public:
1343     // overridden to implement coloring of node idx
1344     virtual void pre_dump(outputStream *st, const Node* n) = 0;
1345     virtual void post_dump(outputStream *st) = 0;
1346   };
1347   void dump_idx(bool align = false, outputStream* st = tty, DumpConfig* dc = nullptr) const;
1348   void dump_name(outputStream* st = tty, DumpConfig* dc = nullptr) const;
1349   void dump() const; // print node with newline
1350   void dump(const char* suffix, bool mark = false, outputStream* st = tty, DumpConfig* dc = nullptr) const; // Print this node.
1351   void dump(int depth) const;        // Print this node, recursively to depth d
1352   void dump_ctrl(int depth) const;   // Print control nodes, to depth d
1353   void dump_comp() const;            // Print this node in compact representation.
1354   // Print this node in compact representation.
1355   void dump_comp(const char* suffix, outputStream *st = tty) const;
1356  private:
1357   virtual void dump_req(outputStream* st = tty, DumpConfig* dc = nullptr) const;    // Print required-edge info
1358   virtual void dump_prec(outputStream* st = tty, DumpConfig* dc = nullptr) const;   // Print precedence-edge info
1359   virtual void dump_out(outputStream* st = tty, DumpConfig* dc = nullptr) const;    // Print the output edge info
1360  public:
1361   virtual void dump_spec(outputStream *st) const {};      // Print per-node info
1362   // Print compact per-node info
1363   virtual void dump_compact_spec(outputStream *st) const { dump_spec(st); }
1364 
1365   static void verify(int verify_depth, VectorSet& visited, Node_List& worklist);
1366 
1367   // This call defines a class-unique string used to identify class instances
1368   virtual const char *Name() const;
1369 
1370   void dump_format(PhaseRegAlloc *ra) const; // debug access to MachNode::format(...)
1371   static bool in_dump() { return Compile::current()->_in_dump_cnt > 0; } // check if we are in a dump call
1372 #endif
1373 #ifdef ASSERT
1374   void verify_construction();
1375   bool verify_jvms(const JVMState* jvms) const;
1376 
1377   Node* _debug_orig;                   // Original version of this, if any.
1378   Node*  debug_orig() const            { return _debug_orig; }
1379   void   set_debug_orig(Node* orig);   // _debug_orig = orig
1380   void   dump_orig(outputStream *st, bool print_key = true) const;
1381 
1382   uint64_t _debug_idx;                 // Unique value assigned to every node.
1383   uint64_t debug_idx() const           { return _debug_idx; }
1384   void set_debug_idx(uint64_t debug_idx) { _debug_idx = debug_idx; }
1385 
1386   int        _hash_lock;               // Barrier to modifications of nodes in the hash table
1387   void  enter_hash_lock() { ++_hash_lock; assert(_hash_lock < 99, "in too many hash tables?"); }
1388   void   exit_hash_lock() { --_hash_lock; assert(_hash_lock >= 0, "mispaired hash locks"); }
1389 
1390   static void init_NodeProperty();
1391 
1392   #if OPTO_DU_ITERATOR_ASSERT
1393   const Node* _last_del;               // The last deleted node.
1394   uint        _del_tick;               // Bumped when a deletion happens..
1395   #endif
1396 #endif
1397 };
1398 
1399 inline bool not_a_node(const Node* n) {
1400   if (n == nullptr)                return true;
1401   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
1402   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
1403   return false;
1404 }
1405 
1406 //-----------------------------------------------------------------------------
1407 // Iterators over DU info, and associated Node functions.
1408 
1409 #if OPTO_DU_ITERATOR_ASSERT
1410 
1411 // Common code for assertion checking on DU iterators.
1412 class DUIterator_Common {
1413 #ifdef ASSERT
1414  protected:
1415   bool         _vdui;               // cached value of VerifyDUIterators
1416   const Node*  _node;               // the node containing the _out array
1417   uint         _outcnt;             // cached node->_outcnt
1418   uint         _del_tick;           // cached node->_del_tick
1419   Node*        _last;               // last value produced by the iterator
1420 
1421   void sample(const Node* node);    // used by c'tor to set up for verifies
1422   void verify(const Node* node, bool at_end_ok = false);
1423   void verify_resync();
1424   void reset(const DUIterator_Common& that);
1425 
1426 // The VDUI_ONLY macro protects code conditionalized on VerifyDUIterators
1427   #define I_VDUI_ONLY(i,x) { if ((i)._vdui) { x; } }
1428 #else
1429   #define I_VDUI_ONLY(i,x) { }
1430 #endif //ASSERT
1431 };
1432 
1433 #define VDUI_ONLY(x)     I_VDUI_ONLY(*this, x)
1434 
1435 // Default DU iterator.  Allows appends onto the out array.
1436 // Allows deletion from the out array only at the current point.
1437 // Usage:
1438 //  for (DUIterator i = x->outs(); x->has_out(i); i++) {
1439 //    Node* y = x->out(i);
1440 //    ...
1441 //  }
1442 // Compiles in product mode to a unsigned integer index, which indexes
1443 // onto a repeatedly reloaded base pointer of x->_out.  The loop predicate
1444 // also reloads x->_outcnt.  If you delete, you must perform "--i" just
1445 // before continuing the loop.  You must delete only the last-produced
1446 // edge.  You must delete only a single copy of the last-produced edge,
1447 // or else you must delete all copies at once (the first time the edge
1448 // is produced by the iterator).
1449 class DUIterator : public DUIterator_Common {
1450   friend class Node;
1451 
1452   // This is the index which provides the product-mode behavior.
1453   // Whatever the product-mode version of the system does to the
1454   // DUI index is done to this index.  All other fields in
1455   // this class are used only for assertion checking.
1456   uint         _idx;
1457 
1458   #ifdef ASSERT
1459   uint         _refresh_tick;    // Records the refresh activity.
1460 
1461   void sample(const Node* node); // Initialize _refresh_tick etc.
1462   void verify(const Node* node, bool at_end_ok = false);
1463   void verify_increment();       // Verify an increment operation.
1464   void verify_resync();          // Verify that we can back up over a deletion.
1465   void verify_finish();          // Verify that the loop terminated properly.
1466   void refresh();                // Resample verification info.
1467   void reset(const DUIterator& that);  // Resample after assignment.
1468   #endif
1469 
1470   DUIterator(const Node* node, int dummy_to_avoid_conversion)
1471     { _idx = 0;                         DEBUG_ONLY(sample(node)); }
1472 
1473  public:
1474   // initialize to garbage; clear _vdui to disable asserts
1475   DUIterator()
1476     { /*initialize to garbage*/         DEBUG_ONLY(_vdui = false); }
1477 
1478   DUIterator(const DUIterator& that)
1479     { _idx = that._idx;                 DEBUG_ONLY(_vdui = false; reset(that)); }
1480 
1481   void operator++(int dummy_to_specify_postfix_op)
1482     { _idx++;                           VDUI_ONLY(verify_increment()); }
1483 
1484   void operator--()
1485     { VDUI_ONLY(verify_resync());       --_idx; }
1486 
1487   ~DUIterator()
1488     { VDUI_ONLY(verify_finish()); }
1489 
1490   void operator=(const DUIterator& that)
1491     { _idx = that._idx;                 DEBUG_ONLY(reset(that)); }
1492 };
1493 
1494 DUIterator Node::outs() const
1495   { return DUIterator(this, 0); }
1496 DUIterator& Node::refresh_out_pos(DUIterator& i) const
1497   { I_VDUI_ONLY(i, i.refresh());        return i; }
1498 bool Node::has_out(DUIterator& i) const
1499   { I_VDUI_ONLY(i, i.verify(this,true));return i._idx < _outcnt; }
1500 Node*    Node::out(DUIterator& i) const
1501   { I_VDUI_ONLY(i, i.verify(this));     return DEBUG_ONLY(i._last=) _out[i._idx]; }
1502 
1503 
1504 // Faster DU iterator.  Disallows insertions into the out array.
1505 // Allows deletion from the out array only at the current point.
1506 // Usage:
1507 //  for (DUIterator_Fast imax, i = x->fast_outs(imax); i < imax; i++) {
1508 //    Node* y = x->fast_out(i);
1509 //    ...
1510 //  }
1511 // Compiles in product mode to raw Node** pointer arithmetic, with
1512 // no reloading of pointers from the original node x.  If you delete,
1513 // you must perform "--i; --imax" just before continuing the loop.
1514 // If you delete multiple copies of the same edge, you must decrement
1515 // imax, but not i, multiple times:  "--i, imax -= num_edges".
1516 class DUIterator_Fast : public DUIterator_Common {
1517   friend class Node;
1518   friend class DUIterator_Last;
1519 
1520   // This is the pointer which provides the product-mode behavior.
1521   // Whatever the product-mode version of the system does to the
1522   // DUI pointer is done to this pointer.  All other fields in
1523   // this class are used only for assertion checking.
1524   Node**       _outp;
1525 
1526   #ifdef ASSERT
1527   void verify(const Node* node, bool at_end_ok = false);
1528   void verify_limit();
1529   void verify_resync();
1530   void verify_relimit(uint n);
1531   void reset(const DUIterator_Fast& that);
1532   #endif
1533 
1534   // Note:  offset must be signed, since -1 is sometimes passed
1535   DUIterator_Fast(const Node* node, ptrdiff_t offset)
1536     { _outp = node->_out + offset;      DEBUG_ONLY(sample(node)); }
1537 
1538  public:
1539   // initialize to garbage; clear _vdui to disable asserts
1540   DUIterator_Fast()
1541     { /*initialize to garbage*/         DEBUG_ONLY(_vdui = false); }
1542 
1543   DUIterator_Fast(const DUIterator_Fast& that)
1544     { _outp = that._outp;               DEBUG_ONLY(_vdui = false; reset(that)); }
1545 
1546   void operator++(int dummy_to_specify_postfix_op)
1547     { _outp++;                          VDUI_ONLY(verify(_node, true)); }
1548 
1549   void operator--()
1550     { VDUI_ONLY(verify_resync());       --_outp; }
1551 
1552   void operator-=(uint n)   // applied to the limit only
1553     { _outp -= n;           VDUI_ONLY(verify_relimit(n));  }
1554 
1555   bool operator<(DUIterator_Fast& limit) {
1556     I_VDUI_ONLY(*this, this->verify(_node, true));
1557     I_VDUI_ONLY(limit, limit.verify_limit());
1558     return _outp < limit._outp;
1559   }
1560 
1561   void operator=(const DUIterator_Fast& that)
1562     { _outp = that._outp;               DEBUG_ONLY(reset(that)); }
1563 };
1564 
1565 DUIterator_Fast Node::fast_outs(DUIterator_Fast& imax) const {
1566   // Assign a limit pointer to the reference argument:
1567   imax = DUIterator_Fast(this, (ptrdiff_t)_outcnt);
1568   // Return the base pointer:
1569   return DUIterator_Fast(this, 0);
1570 }
1571 Node* Node::fast_out(DUIterator_Fast& i) const {
1572   I_VDUI_ONLY(i, i.verify(this));
1573   return DEBUG_ONLY(i._last=) *i._outp;
1574 }
1575 
1576 
1577 // Faster DU iterator.  Requires each successive edge to be removed.
1578 // Does not allow insertion of any edges.
1579 // Usage:
1580 //  for (DUIterator_Last imin, i = x->last_outs(imin); i >= imin; i -= num_edges) {
1581 //    Node* y = x->last_out(i);
1582 //    ...
1583 //  }
1584 // Compiles in product mode to raw Node** pointer arithmetic, with
1585 // no reloading of pointers from the original node x.
1586 class DUIterator_Last : private DUIterator_Fast {
1587   friend class Node;
1588 
1589   #ifdef ASSERT
1590   void verify(const Node* node, bool at_end_ok = false);
1591   void verify_limit();
1592   void verify_step(uint num_edges);
1593   #endif
1594 
1595   // Note:  offset must be signed, since -1 is sometimes passed
1596   DUIterator_Last(const Node* node, ptrdiff_t offset)
1597     : DUIterator_Fast(node, offset) { }
1598 
1599   void operator++(int dummy_to_specify_postfix_op) {} // do not use
1600   void operator<(int)                              {} // do not use
1601 
1602  public:
1603   DUIterator_Last() { }
1604   // initialize to garbage
1605 
1606   DUIterator_Last(const DUIterator_Last& that) = default;
1607 
1608   void operator--()
1609     { _outp--;              VDUI_ONLY(verify_step(1));  }
1610 
1611   void operator-=(uint n)
1612     { _outp -= n;           VDUI_ONLY(verify_step(n));  }
1613 
1614   bool operator>=(DUIterator_Last& limit) {
1615     I_VDUI_ONLY(*this, this->verify(_node, true));
1616     I_VDUI_ONLY(limit, limit.verify_limit());
1617     return _outp >= limit._outp;
1618   }
1619 
1620   DUIterator_Last& operator=(const DUIterator_Last& that) = default;
1621 };
1622 
1623 DUIterator_Last Node::last_outs(DUIterator_Last& imin) const {
1624   // Assign a limit pointer to the reference argument:
1625   imin = DUIterator_Last(this, 0);
1626   // Return the initial pointer:
1627   return DUIterator_Last(this, (ptrdiff_t)_outcnt - 1);
1628 }
1629 Node* Node::last_out(DUIterator_Last& i) const {
1630   I_VDUI_ONLY(i, i.verify(this));
1631   return DEBUG_ONLY(i._last=) *i._outp;
1632 }
1633 
1634 #endif //OPTO_DU_ITERATOR_ASSERT
1635 
1636 #undef I_VDUI_ONLY
1637 #undef VDUI_ONLY
1638 
1639 // An Iterator that truly follows the iterator pattern.  Doesn't
1640 // support deletion but could be made to.
1641 //
1642 //   for (SimpleDUIterator i(n); i.has_next(); i.next()) {
1643 //     Node* m = i.get();
1644 //
1645 class SimpleDUIterator : public StackObj {
1646  private:
1647   Node* node;
1648   DUIterator_Fast imax;
1649   DUIterator_Fast i;
1650  public:
1651   SimpleDUIterator(Node* n): node(n), i(n->fast_outs(imax)) {}
1652   bool has_next() { return i < imax; }
1653   void next() { i++; }
1654   Node* get() { return node->fast_out(i); }
1655 };
1656 
1657 
1658 //-----------------------------------------------------------------------------
1659 // Map dense integer indices to Nodes.  Uses classic doubling-array trick.
1660 // Abstractly provides an infinite array of Node*'s, initialized to null.
1661 // Note that the constructor just zeros things, and since I use Arena
1662 // allocation I do not need a destructor to reclaim storage.
1663 class Node_Array : public AnyObj {
1664 protected:
1665   Arena* _a;                    // Arena to allocate in
1666   uint   _max;
1667   Node** _nodes;
1668   ReallocMark _nesting;         // Safety checks for arena reallocation
1669 
1670   // Grow array to required capacity
1671   void maybe_grow(uint i) {
1672     _nesting.check(_a); // Check if a potential reallocation in the arena is safe
1673     if (i >= _max) {
1674       grow(i);
1675     }
1676   }
1677   void grow(uint i);
1678 
1679 public:
1680   Node_Array(Arena* a, uint max = OptoNodeListSize) : _a(a), _max(max) {
1681     _nodes = NEW_ARENA_ARRAY(a, Node*, max);
1682     clear();
1683   }
1684   Node_Array() : Node_Array(Thread::current()->resource_area()) {}
1685 
1686   NONCOPYABLE(Node_Array);
1687   Node_Array& operator=(Node_Array&&) = delete;
1688   // Allow move constructor for && (eg. capture return of function)
1689   Node_Array(Node_Array&&) = default;
1690 
1691   Node *operator[] ( uint i ) const // Lookup, or null for not mapped
1692   { return (i<_max) ? _nodes[i] : (Node*)nullptr; }
1693   Node* at(uint i) const { assert(i<_max,"oob"); return _nodes[i]; }
1694   Node** adr() { return _nodes; }
1695   // Extend the mapping: index i maps to Node *n.
1696   void map( uint i, Node *n ) { maybe_grow(i); _nodes[i] = n; }
1697   void insert( uint i, Node *n );
1698   void remove( uint i );        // Remove, preserving order
1699   // Clear all entries in _nodes to null but keep storage
1700   void clear() {
1701     Copy::zero_to_bytes(_nodes, _max * sizeof(Node*));
1702   }
1703 
1704   uint max() const { return _max; }
1705   void dump() const;
1706 };
1707 
1708 class Node_List : public Node_Array {
1709   uint _cnt;
1710 public:
1711   Node_List(uint max = OptoNodeListSize) : Node_Array(Thread::current()->resource_area(), max), _cnt(0) {}
1712   Node_List(Arena *a, uint max = OptoNodeListSize) : Node_Array(a, max), _cnt(0) {}
1713 
1714   NONCOPYABLE(Node_List);
1715   Node_List& operator=(Node_List&&) = delete;
1716   // Allow move constructor for && (eg. capture return of function)
1717   Node_List(Node_List&&) = default;
1718 
1719   bool contains(const Node* n) const {
1720     for (uint e = 0; e < size(); e++) {
1721       if (at(e) == n) return true;
1722     }
1723     return false;
1724   }
1725   void insert( uint i, Node *n ) { Node_Array::insert(i,n); _cnt++; }
1726   void remove( uint i ) { Node_Array::remove(i); _cnt--; }
1727   void push( Node *b ) { map(_cnt++,b); }
1728   void yank( Node *n );         // Find and remove
1729   Node *pop() { return _nodes[--_cnt]; }
1730   void clear() { _cnt = 0; Node_Array::clear(); } // retain storage
1731   void copy(const Node_List& from) {
1732     if (from._max > _max) {
1733       grow(from._max);
1734     }
1735     _cnt = from._cnt;
1736     Copy::conjoint_words_to_higher((HeapWord*)&from._nodes[0], (HeapWord*)&_nodes[0], from._max * sizeof(Node*));
1737   }
1738 
1739   uint size() const { return _cnt; }
1740   void dump() const;
1741   void dump_simple() const;
1742 };
1743 
1744 // Definition must appear after complete type definition of Node_List
1745 template <typename Callback, typename Check>
1746 void Node::visit_uses(Callback callback, Check is_boundary) const {
1747   ResourceMark rm;
1748   VectorSet visited;
1749   Node_List worklist;
1750 
1751   // The initial worklist consists of the direct uses
1752   for (DUIterator_Fast kmax, k = fast_outs(kmax); k < kmax; k++) {
1753     Node* out = fast_out(k);
1754     if (!visited.test_set(out->_idx)) { worklist.push(out); }
1755   }
1756 
1757   while (worklist.size() > 0) {
1758     Node* use = worklist.pop();
1759     // Apply callback on boundary nodes
1760     if (is_boundary(use)) {
1761       callback(use);
1762     } else {
1763       // Not a boundary node, continue search
1764       for (DUIterator_Fast kmax, k = use->fast_outs(kmax); k < kmax; k++) {
1765         Node* out = use->fast_out(k);
1766         if (!visited.test_set(out->_idx)) { worklist.push(out); }
1767       }
1768     }
1769   }
1770 }
1771 
1772 
1773 //------------------------------Unique_Node_List-------------------------------
1774 class Unique_Node_List : public Node_List {
1775   VectorSet _in_worklist;
1776   uint _clock_index;            // Index in list where to pop from next
1777 public:
1778   Unique_Node_List() : Node_List(), _clock_index(0) {}
1779   Unique_Node_List(Arena *a) : Node_List(a), _in_worklist(a), _clock_index(0) {}
1780 
1781   NONCOPYABLE(Unique_Node_List);
1782   Unique_Node_List& operator=(Unique_Node_List&&) = delete;
1783   // Allow move constructor for && (eg. capture return of function)
1784   Unique_Node_List(Unique_Node_List&&) = default;
1785 
1786   void remove( Node *n );
1787   bool member(const Node* n) const { return _in_worklist.test(n->_idx) != 0; }
1788   VectorSet& member_set(){ return _in_worklist; }
1789 
1790   void push(Node* b) {
1791     if( !_in_worklist.test_set(b->_idx) )
1792       Node_List::push(b);
1793   }
1794   void push_non_cfg_inputs_of(const Node* node) {
1795     for (uint i = 1; i < node->req(); i++) {
1796       Node* input = node->in(i);
1797       if (input != nullptr && !input->is_CFG()) {
1798         push(input);
1799       }
1800     }
1801   }
1802 
1803   void push_outputs_of(const Node* node) {
1804     for (DUIterator_Fast imax, i = node->fast_outs(imax); i < imax; i++) {
1805       Node* output = node->fast_out(i);
1806       push(output);
1807     }
1808   }
1809 
1810   Node *pop() {
1811     if( _clock_index >= size() ) _clock_index = 0;
1812     Node *b = at(_clock_index);
1813     map( _clock_index, Node_List::pop());
1814     if (size() != 0) _clock_index++; // Always start from 0
1815     _in_worklist.remove(b->_idx);
1816     return b;
1817   }
1818   Node *remove(uint i) {
1819     Node *b = Node_List::at(i);
1820     _in_worklist.remove(b->_idx);
1821     map(i,Node_List::pop());
1822     return b;
1823   }
1824   void yank(Node *n) {
1825     _in_worklist.remove(n->_idx);
1826     Node_List::yank(n);
1827   }
1828   void  clear() {
1829     _in_worklist.clear();        // Discards storage but grows automatically
1830     Node_List::clear();
1831     _clock_index = 0;
1832   }
1833   void ensure_empty() {
1834     assert(size() == 0, "must be empty");
1835     clear(); // just in case
1836   }
1837 
1838   // Used after parsing to remove useless nodes before Iterative GVN
1839   void remove_useless_nodes(VectorSet& useful);
1840 
1841   // If the idx of the Nodes change, we must recompute the VectorSet
1842   void recompute_idx_set() {
1843     _in_worklist.clear();
1844     for (uint i = 0; i < size(); i++) {
1845       Node* n = at(i);
1846       _in_worklist.set(n->_idx);
1847     }
1848   }
1849 
1850 #ifdef ASSERT
1851   bool is_subset_of(Unique_Node_List& other) {
1852     for (uint i = 0; i < size(); i++) {
1853       Node* n = at(i);
1854       if (!other.member(n)) {
1855         return false;
1856       }
1857     }
1858     return true;
1859   }
1860 #endif
1861 
1862   bool contains(const Node* n) const {
1863     fatal("use faster member() instead");
1864     return false;
1865   }
1866 
1867 #ifndef PRODUCT
1868   void print_set() const { _in_worklist.print(); }
1869 #endif
1870 };
1871 
1872 // Unique_Mixed_Node_List
1873 // unique: nodes are added only once
1874 // mixed: allow new and old nodes
1875 class Unique_Mixed_Node_List : public ResourceObj {
1876 public:
1877   Unique_Mixed_Node_List() : _visited_set(cmpkey, hashkey) {}
1878 
1879   void add(Node* node) {
1880     if (not_a_node(node)) {
1881       return; // Gracefully handle null, -1, 0xabababab, etc.
1882     }
1883     if (_visited_set[node] == nullptr) {
1884       _visited_set.Insert(node, node);
1885       _worklist.push(node);
1886     }
1887   }
1888 
1889   Node* operator[] (uint i) const {
1890     return _worklist[i];
1891   }
1892 
1893   size_t size() {
1894     return _worklist.size();
1895   }
1896 
1897 private:
1898   Dict _visited_set;
1899   Node_List _worklist;
1900 };
1901 
1902 // Inline definition of Compile::record_for_igvn must be deferred to this point.
1903 inline void Compile::record_for_igvn(Node* n) {
1904   _igvn_worklist->push(n);
1905 }
1906 
1907 // Inline definition of Compile::remove_for_igvn must be deferred to this point.
1908 inline void Compile::remove_for_igvn(Node* n) {
1909   _igvn_worklist->remove(n);
1910 }
1911 
1912 //------------------------------Node_Stack-------------------------------------
1913 class Node_Stack {
1914 protected:
1915   struct INode {
1916     Node *node; // Processed node
1917     uint  indx; // Index of next node's child
1918   };
1919   INode *_inode_top; // tos, stack grows up
1920   INode *_inode_max; // End of _inodes == _inodes + _max
1921   INode *_inodes;    // Array storage for the stack
1922   Arena *_a;         // Arena to allocate in
1923   ReallocMark _nesting; // Safety checks for arena reallocation
1924 
1925   void maybe_grow() {
1926     _nesting.check(_a); // Check if a potential reallocation in the arena is safe
1927     if (_inode_top >= _inode_max) {
1928       grow();
1929     }
1930   }
1931   void grow();
1932 
1933 public:
1934   Node_Stack(int size) {
1935     size_t max = (size > OptoNodeListSize) ? size : OptoNodeListSize;
1936     _a = Thread::current()->resource_area();
1937     _inodes = NEW_ARENA_ARRAY( _a, INode, max );
1938     _inode_max = _inodes + max;
1939     _inode_top = _inodes - 1; // stack is empty
1940   }
1941 
1942   Node_Stack(Arena *a, int size) : _a(a) {
1943     size_t max = (size > OptoNodeListSize) ? size : OptoNodeListSize;
1944     _inodes = NEW_ARENA_ARRAY( _a, INode, max );
1945     _inode_max = _inodes + max;
1946     _inode_top = _inodes - 1; // stack is empty
1947   }
1948 
1949   void pop() {
1950     assert(_inode_top >= _inodes, "node stack underflow");
1951     --_inode_top;
1952   }
1953   void push(Node *n, uint i) {
1954     ++_inode_top;
1955     maybe_grow();
1956     INode *top = _inode_top; // optimization
1957     top->node = n;
1958     top->indx = i;
1959   }
1960   Node *node() const {
1961     return _inode_top->node;
1962   }
1963   Node* node_at(uint i) const {
1964     assert(_inodes + i <= _inode_top, "in range");
1965     return _inodes[i].node;
1966   }
1967   uint index() const {
1968     return _inode_top->indx;
1969   }
1970   uint index_at(uint i) const {
1971     assert(_inodes + i <= _inode_top, "in range");
1972     return _inodes[i].indx;
1973   }
1974   void set_node(Node *n) {
1975     _inode_top->node = n;
1976   }
1977   void set_index(uint i) {
1978     _inode_top->indx = i;
1979   }
1980   uint size_max() const { return (uint)pointer_delta(_inode_max, _inodes,  sizeof(INode)); } // Max size
1981   uint size() const { return (uint)pointer_delta((_inode_top+1), _inodes,  sizeof(INode)); } // Current size
1982   bool is_nonempty() const { return (_inode_top >= _inodes); }
1983   bool is_empty() const { return (_inode_top < _inodes); }
1984   void clear() { _inode_top = _inodes - 1; } // retain storage
1985 
1986   // Node_Stack is used to map nodes.
1987   Node* find(uint idx) const;
1988 
1989   NONCOPYABLE(Node_Stack);
1990 };
1991 
1992 
1993 //-----------------------------Node_Notes--------------------------------------
1994 // Debugging or profiling annotations loosely and sparsely associated
1995 // with some nodes.  See Compile::node_notes_at for the accessor.
1996 class Node_Notes {
1997   JVMState* _jvms;
1998 
1999 public:
2000   Node_Notes(JVMState* jvms = nullptr) {
2001     _jvms = jvms;
2002   }
2003 
2004   JVMState* jvms()            { return _jvms; }
2005   void  set_jvms(JVMState* x) {        _jvms = x; }
2006 
2007   // True if there is nothing here.
2008   bool is_clear() {
2009     return (_jvms == nullptr);
2010   }
2011 
2012   // Make there be nothing here.
2013   void clear() {
2014     _jvms = nullptr;
2015   }
2016 
2017   // Make a new, clean node notes.
2018   static Node_Notes* make(Compile* C) {
2019     Node_Notes* nn = NEW_ARENA_ARRAY(C->comp_arena(), Node_Notes, 1);
2020     nn->clear();
2021     return nn;
2022   }
2023 
2024   Node_Notes* clone(Compile* C) {
2025     Node_Notes* nn = NEW_ARENA_ARRAY(C->comp_arena(), Node_Notes, 1);
2026     (*nn) = (*this);
2027     return nn;
2028   }
2029 
2030   // Absorb any information from source.
2031   bool update_from(Node_Notes* source) {
2032     bool changed = false;
2033     if (source != nullptr) {
2034       if (source->jvms() != nullptr) {
2035         set_jvms(source->jvms());
2036         changed = true;
2037       }
2038     }
2039     return changed;
2040   }
2041 };
2042 
2043 // Inlined accessors for Compile::node_nodes that require the preceding class:
2044 inline Node_Notes*
2045 Compile::locate_node_notes(GrowableArray<Node_Notes*>* arr,
2046                            int idx, bool can_grow) {
2047   assert(idx >= 0, "oob");
2048   int block_idx = (idx >> _log2_node_notes_block_size);
2049   int grow_by = (block_idx - (arr == nullptr? 0: arr->length()));
2050   if (grow_by >= 0) {
2051     if (!can_grow) return nullptr;
2052     grow_node_notes(arr, grow_by + 1);
2053   }
2054   if (arr == nullptr) return nullptr;
2055   // (Every element of arr is a sub-array of length _node_notes_block_size.)
2056   return arr->at(block_idx) + (idx & (_node_notes_block_size-1));
2057 }
2058 
2059 inline Node_Notes* Compile::node_notes_at(int idx) {
2060   return locate_node_notes(_node_note_array, idx, false);
2061 }
2062 
2063 inline bool
2064 Compile::set_node_notes_at(int idx, Node_Notes* value) {
2065   if (value == nullptr || value->is_clear())
2066     return false;  // nothing to write => write nothing
2067   Node_Notes* loc = locate_node_notes(_node_note_array, idx, true);
2068   assert(loc != nullptr, "");
2069   return loc->update_from(value);
2070 }
2071 
2072 
2073 //------------------------------TypeNode---------------------------------------
2074 // Node with a Type constant.
2075 class TypeNode : public Node {
2076 protected:
2077   virtual uint hash() const;    // Check the type
2078   virtual bool cmp( const Node &n ) const;
2079   virtual uint size_of() const; // Size is bigger
2080   const Type* const _type;
2081 public:
2082   void set_type(const Type* t) {
2083     assert(t != nullptr, "sanity");
2084     DEBUG_ONLY(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
2085     *(const Type**)&_type = t;   // cast away const-ness
2086     // If this node is in the hash table, make sure it doesn't need a rehash.
2087     assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
2088   }
2089   const Type* type() const { assert(_type != nullptr, "sanity"); return _type; };
2090   TypeNode( const Type *t, uint required ) : Node(required), _type(t) {
2091     init_class_id(Class_Type);
2092   }
2093   virtual const Type* Value(PhaseGVN* phase) const;
2094   virtual Node* Ideal(PhaseGVN* phase, bool can_reshape);
2095   virtual const Type *bottom_type() const;
2096   virtual       uint  ideal_reg() const;
2097 
2098   void make_path_dead(PhaseIterGVN* igvn, PhaseIdealLoop* loop, Node* ctrl_use, uint j, const char* phase_str);
2099 #ifndef PRODUCT
2100   virtual void dump_spec(outputStream *st) const;
2101   virtual void dump_compact_spec(outputStream *st) const;
2102 #endif
2103   void make_paths_from_here_dead(PhaseIterGVN* igvn, PhaseIdealLoop* loop, const char* phase_str);
2104   void create_halt_path(PhaseIterGVN* igvn, Node* c, PhaseIdealLoop* loop, const char* phase_str) const;
2105 };
2106 
2107 #include "opto/opcodes.hpp"
2108 
2109 #define Op_IL(op) \
2110   inline int Op_ ## op(BasicType bt) { \
2111   assert(bt == T_INT || bt == T_LONG, "only for int or longs"); \
2112   if (bt == T_INT) { \
2113     return Op_## op ## I; \
2114   } \
2115   return Op_## op ## L; \
2116 }
2117 
2118 Op_IL(Add)
2119 Op_IL(And)
2120 Op_IL(Sub)
2121 Op_IL(Mul)
2122 Op_IL(URShift)
2123 Op_IL(LShift)
2124 Op_IL(RShift)
2125 Op_IL(Xor)
2126 Op_IL(Cmp)
2127 Op_IL(Div)
2128 Op_IL(Mod)
2129 Op_IL(UDiv)
2130 Op_IL(UMod)
2131 
2132 inline int Op_ConIL(BasicType bt) {
2133   assert(bt == T_INT || bt == T_LONG, "only for int or longs");
2134   if (bt == T_INT) {
2135     return Op_ConI;
2136   }
2137   return Op_ConL;
2138 }
2139 
2140 inline int Op_Cmp_unsigned(BasicType bt) {
2141   assert(bt == T_INT || bt == T_LONG, "only for int or longs");
2142   if (bt == T_INT) {
2143     return Op_CmpU;
2144   }
2145   return Op_CmpUL;
2146 }
2147 
2148 inline int Op_Cast(BasicType bt) {
2149   assert(bt == T_INT || bt == T_LONG, "only for int or longs");
2150   if (bt == T_INT) {
2151     return Op_CastII;
2152   }
2153   return Op_CastLL;
2154 }
2155 
2156 inline int Op_DivIL(BasicType bt, bool is_unsigned) {
2157   assert(bt == T_INT || bt == T_LONG, "only for int or longs");
2158   if (bt == T_INT) {
2159     if (is_unsigned) {
2160       return Op_UDivI;
2161     } else {
2162       return Op_DivI;
2163     }
2164   }
2165   if (is_unsigned) {
2166     return Op_UDivL;
2167   } else {
2168     return Op_DivL;
2169   }
2170 }
2171 
2172 inline int Op_DivModIL(BasicType bt, bool is_unsigned) {
2173   assert(bt == T_INT || bt == T_LONG, "only for int or longs");
2174   if (bt == T_INT) {
2175     if (is_unsigned) {
2176       return Op_UDivModI;
2177     } else {
2178       return Op_DivModI;
2179     }
2180   }
2181   if (is_unsigned) {
2182     return Op_UDivModL;
2183   } else {
2184     return Op_DivModL;
2185   }
2186 }
2187 
2188 // Interface to define actions that should be taken when running DataNodeBFS. Each use can extend this class to specify
2189 // a customized BFS.
2190 class BFSActions : public StackObj {
2191  public:
2192   // Should a node's inputs further be visited in the BFS traversal? By default, we visit all data inputs. Override this
2193   // method to provide a custom filter.
2194   virtual bool should_visit(Node* node) const {
2195     // By default, visit all inputs.
2196     return true;
2197   };
2198 
2199   // Is the visited node a target node that we are looking for in the BFS traversal? We do not visit its inputs further
2200   // but the BFS will continue to visit all unvisited nodes in the queue.
2201   virtual bool is_target_node(Node* node) const = 0;
2202 
2203   // Defines an action that should be taken when we visit a target node in the BFS traversal.
2204   // To give more freedom, we pass the direct child node to the target node such that
2205   // child->in(i) == target node. This allows to also directly replace the target node instead
2206   // of only updating its inputs.
2207   virtual void target_node_action(Node* child, uint i) = 0;
2208 };
2209 
2210 // Class to perform a BFS traversal on the data nodes from a given start node. The provided BFSActions guide which
2211 // data node's inputs should be further visited, which data nodes are target nodes and what to do with the target nodes.
2212 class DataNodeBFS : public StackObj {
2213   BFSActions& _bfs_actions;
2214 
2215  public:
2216   explicit DataNodeBFS(BFSActions& bfs_action) : _bfs_actions(bfs_action) {}
2217 
2218   // Run the BFS starting from 'start_node' and apply the actions provided to this class.
2219   void run(Node* start_node) {
2220     ResourceMark rm;
2221     Unique_Node_List _nodes_to_visit;
2222     _nodes_to_visit.push(start_node);
2223     for (uint i = 0; i < _nodes_to_visit.size(); i++) {
2224       Node* next = _nodes_to_visit[i];
2225       for (uint j = 1; j < next->req(); j++) {
2226         Node* input = next->in(j);
2227         if (_bfs_actions.is_target_node(input)) {
2228           assert(_bfs_actions.should_visit(input), "must also pass node filter");
2229           _bfs_actions.target_node_action(next, j);
2230         } else if (_bfs_actions.should_visit(input)) {
2231           _nodes_to_visit.push(input);
2232         }
2233       }
2234     }
2235   }
2236 };
2237 
2238 #endif // SHARE_OPTO_NODE_HPP