1 /*
   2  * Copyright 1997-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 class PhaseTransform;
  26 class MachNode;
  27 
  28 //------------------------------ConNode----------------------------------------
  29 // Simple constants
  30 class ConNode : public TypeNode {
  31 public:
  32   ConNode( const Type *t ) : TypeNode(t,1) {
  33     init_req(0, (Node*)Compile::current()->root());
  34     init_flags(Flag_is_Con);
  35   }
  36   virtual int  Opcode() const;
  37   virtual uint hash() const;
  38   virtual const RegMask &out_RegMask() const { return RegMask::Empty; }
  39   virtual const RegMask &in_RegMask(uint) const { return RegMask::Empty; }
  40 
  41   // Polymorphic factory method:
  42   static ConNode* make( Compile* C, const Type *t );
  43 };
  44 
  45 //------------------------------ConINode---------------------------------------
  46 // Simple integer constants
  47 class ConINode : public ConNode {
  48 public:
  49   ConINode( const TypeInt *t ) : ConNode(t) {}
  50   virtual int Opcode() const;
  51 
  52   // Factory method:
  53   static ConINode* make( Compile* C, int con ) {
  54     return new (C, 1) ConINode( TypeInt::make(con) );
  55   }
  56 
  57 };
  58 
  59 //------------------------------ConPNode---------------------------------------
  60 // Simple pointer constants
  61 class ConPNode : public ConNode {
  62 public:
  63   ConPNode( const TypePtr *t ) : ConNode(t) {}
  64   virtual int Opcode() const;
  65 
  66   // Factory methods:
  67   static ConPNode* make( Compile *C ,address con ) {
  68     if (con == NULL)
  69       return new (C, 1) ConPNode( TypePtr::NULL_PTR ) ;
  70     else
  71       return new (C, 1) ConPNode( TypeRawPtr::make(con) );
  72   }
  73 
  74   static ConPNode* make( Compile *C, ciObject* con ) {
  75     return new (C, 1) ConPNode( TypeOopPtr::make_from_constant(con) );
  76   }
  77 
  78 };
  79 
  80 
  81 //------------------------------ConNNode--------------------------------------
  82 // Simple narrow oop constants
  83 class ConNNode : public ConNode {
  84 public:
  85   ConNNode( const TypeNarrowOop *t ) : ConNode(t) {}
  86   virtual int Opcode() const;
  87 
  88   static ConNNode* make( Compile *C, ciObject* con ) {
  89     return new (C, 1) ConNNode( TypeNarrowOop::make_from_constant(con) );
  90   }
  91 
  92 };
  93 
  94 
  95 //------------------------------ConLNode---------------------------------------
  96 // Simple long constants
  97 class ConLNode : public ConNode {
  98 public:
  99   ConLNode( const TypeLong *t ) : ConNode(t) {}
 100   virtual int Opcode() const;
 101 
 102   // Factory method:
 103   static ConLNode* make( Compile *C ,jlong con ) {
 104     return new (C, 1) ConLNode( TypeLong::make(con) );
 105   }
 106 
 107 };
 108 
 109 //------------------------------ConFNode---------------------------------------
 110 // Simple float constants
 111 class ConFNode : public ConNode {
 112 public:
 113   ConFNode( const TypeF *t ) : ConNode(t) {}
 114   virtual int Opcode() const;
 115 
 116   // Factory method:
 117   static ConFNode* make( Compile *C, float con  ) {
 118     return new (C, 1) ConFNode( TypeF::make(con) );
 119   }
 120 
 121 };
 122 
 123 //------------------------------ConDNode---------------------------------------
 124 // Simple double constants
 125 class ConDNode : public ConNode {
 126 public:
 127   ConDNode( const TypeD *t ) : ConNode(t) {}
 128   virtual int Opcode() const;
 129 
 130   // Factory method:
 131   static ConDNode* make( Compile *C, double con ) {
 132     return new (C, 1) ConDNode( TypeD::make(con) );
 133   }
 134 
 135 };
 136 
 137 //------------------------------BinaryNode-------------------------------------
 138 // Place holder for the 2 conditional inputs to a CMove.  CMove needs 4
 139 // inputs: the Bool (for the lt/gt/eq/ne bits), the flags (result of some
 140 // compare), and the 2 values to select between.  The Matcher requires a
 141 // binary tree so we break it down like this:
 142 //     (CMove (Binary bol cmp) (Binary src1 src2))
 143 class BinaryNode : public Node {
 144 public:
 145   BinaryNode( Node *n1, Node *n2 ) : Node(0,n1,n2) { }
 146   virtual int Opcode() const;
 147   virtual uint ideal_reg() const { return 0; }
 148 };
 149 
 150 //------------------------------CMoveNode--------------------------------------
 151 // Conditional move
 152 class CMoveNode : public TypeNode {
 153 public:
 154   enum { Control,               // When is it safe to do this cmove?
 155          Condition,             // Condition controlling the cmove
 156          IfFalse,               // Value if condition is false
 157          IfTrue };              // Value if condition is true
 158   CMoveNode( Node *bol, Node *left, Node *right, const Type *t ) : TypeNode(t,4)
 159   {
 160     init_class_id(Class_CMove);
 161     // all inputs are nullified in Node::Node(int)
 162     // init_req(Control,NULL);
 163     init_req(Condition,bol);
 164     init_req(IfFalse,left);
 165     init_req(IfTrue,right);
 166   }
 167   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 168   virtual const Type *Value( PhaseTransform *phase ) const;
 169   virtual Node *Identity( PhaseTransform *phase );
 170   static CMoveNode *make( Compile *C, Node *c, Node *bol, Node *left, Node *right, const Type *t );
 171   // Helper function to spot cmove graph shapes
 172   static Node *is_cmove_id( PhaseTransform *phase, Node *cmp, Node *t, Node *f, BoolNode *b );
 173 };
 174 
 175 //------------------------------CMoveDNode-------------------------------------
 176 class CMoveDNode : public CMoveNode {
 177 public:
 178   CMoveDNode( Node *bol, Node *left, Node *right, const Type* t) : CMoveNode(bol,left,right,t){}
 179   virtual int Opcode() const;
 180   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 181 };
 182 
 183 //------------------------------CMoveFNode-------------------------------------
 184 class CMoveFNode : public CMoveNode {
 185 public:
 186   CMoveFNode( Node *bol, Node *left, Node *right, const Type* t ) : CMoveNode(bol,left,right,t) {}
 187   virtual int Opcode() const;
 188   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 189 };
 190 
 191 //------------------------------CMoveINode-------------------------------------
 192 class CMoveINode : public CMoveNode {
 193 public:
 194   CMoveINode( Node *bol, Node *left, Node *right, const TypeInt *ti ) : CMoveNode(bol,left,right,ti){}
 195   virtual int Opcode() const;
 196   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 197 };
 198 
 199 //------------------------------CMoveLNode-------------------------------------
 200 class CMoveLNode : public CMoveNode {
 201 public:
 202   CMoveLNode(Node *bol, Node *left, Node *right, const TypeLong *tl ) : CMoveNode(bol,left,right,tl){}
 203   virtual int Opcode() const;
 204 };
 205 
 206 //------------------------------CMovePNode-------------------------------------
 207 class CMovePNode : public CMoveNode {
 208 public:
 209   CMovePNode( Node *c, Node *bol, Node *left, Node *right, const TypePtr* t ) : CMoveNode(bol,left,right,t) { init_req(Control,c); }
 210   virtual int Opcode() const;
 211 };
 212 
 213 //------------------------------ConstraintCastNode-------------------------------------
 214 // cast to a different range
 215 class ConstraintCastNode: public TypeNode {
 216 public:
 217   ConstraintCastNode (Node *n, const Type *t ): TypeNode(t,2) {
 218     init_class_id(Class_ConstraintCast);
 219     init_req(1, n);
 220   }
 221   virtual Node *Identity( PhaseTransform *phase );
 222   virtual const Type *Value( PhaseTransform *phase ) const;
 223   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 224   virtual int Opcode() const;
 225   virtual uint ideal_reg() const = 0;
 226   virtual Node *Ideal_DU_postCCP( PhaseCCP * );
 227 };
 228 
 229 //------------------------------CastIINode-------------------------------------
 230 // cast integer to integer (different range)
 231 class CastIINode: public ConstraintCastNode {
 232 public:
 233   CastIINode (Node *n, const Type *t ): ConstraintCastNode(n,t) {}
 234   virtual int Opcode() const;
 235   virtual uint ideal_reg() const { return Op_RegI; }
 236 };
 237 
 238 //------------------------------CastPPNode-------------------------------------
 239 // cast pointer to pointer (different type)
 240 class CastPPNode: public ConstraintCastNode {
 241 public:
 242   CastPPNode (Node *n, const Type *t ): ConstraintCastNode(n, t) {
 243     // Only CastPP is safe.  CastII can cause optimizer loops.
 244     init_flags(Flag_is_dead_loop_safe);
 245   }
 246   virtual int Opcode() const;
 247   virtual uint ideal_reg() const { return Op_RegP; }
 248   virtual Node *Ideal_DU_postCCP( PhaseCCP * );
 249 };
 250 
 251 //------------------------------CheckCastPPNode--------------------------------
 252 // for _checkcast, cast pointer to pointer (different type), without JOIN,
 253 class CheckCastPPNode: public TypeNode {
 254 public:
 255   CheckCastPPNode( Node *c, Node *n, const Type *t ) : TypeNode(t,2) {
 256     init_class_id(Class_CheckCastPP);
 257     init_flags(Flag_is_dead_loop_safe);
 258     init_req(0, c);
 259     init_req(1, n);
 260   }
 261   virtual Node *Identity( PhaseTransform *phase );
 262   virtual const Type *Value( PhaseTransform *phase ) const;
 263   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 264   virtual int   Opcode() const;
 265   virtual uint  ideal_reg() const { return Op_RegP; }
 266   // No longer remove CheckCast after CCP as it gives me a place to hang
 267   // the proper address type - which is required to compute anti-deps.
 268   //virtual Node *Ideal_DU_postCCP( PhaseCCP * );
 269 };
 270 
 271 
 272 //------------------------------EncodeP--------------------------------
 273 // Encodes an oop pointers into its compressed form
 274 // Takes an extra argument which is the real heap base as a long which
 275 // may be useful for code generation in the backend.
 276 class EncodePNode : public TypeNode {
 277  public:
 278   EncodePNode(Node* value, const Type* type):
 279     TypeNode(type, 2) {
 280     init_req(0, NULL);
 281     init_req(1, value);
 282   }
 283   virtual int Opcode() const;
 284   virtual Node *Identity( PhaseTransform *phase );
 285   virtual uint  ideal_reg() const { return Op_RegN; }
 286 
 287   static Node* encode(PhaseGVN* phase, Node* value);
 288 };
 289 
 290 //------------------------------DecodeN--------------------------------
 291 // Converts a narrow oop into a real oop ptr.
 292 // Takes an extra argument which is the real heap base as a long which
 293 // may be useful for code generation in the backend.
 294 class DecodeNNode : public TypeNode {
 295  public:
 296   DecodeNNode(Node* value, const Type* type):
 297     TypeNode(type, 2) {
 298     init_req(0, NULL);
 299     init_req(1, value);
 300   }
 301   virtual int Opcode() const;
 302   virtual Node *Identity( PhaseTransform *phase );
 303   virtual uint  ideal_reg() const { return Op_RegP; }
 304 };
 305 
 306 //------------------------------Conv2BNode-------------------------------------
 307 // Convert int/pointer to a Boolean.  Map zero to zero, all else to 1.
 308 class Conv2BNode : public Node {
 309 public:
 310   Conv2BNode( Node *i ) : Node(0,i) {}
 311   virtual int Opcode() const;
 312   virtual const Type *bottom_type() const { return TypeInt::BOOL; }
 313   virtual Node *Identity( PhaseTransform *phase );
 314   virtual const Type *Value( PhaseTransform *phase ) const;
 315   virtual uint  ideal_reg() const { return Op_RegI; }
 316 };
 317 
 318 // The conversions operations are all Alpha sorted.  Please keep it that way!
 319 //------------------------------ConvD2FNode------------------------------------
 320 // Convert double to float
 321 class ConvD2FNode : public Node {
 322 public:
 323   ConvD2FNode( Node *in1 ) : Node(0,in1) {}
 324   virtual int Opcode() const;
 325   virtual const Type *bottom_type() const { return Type::FLOAT; }
 326   virtual const Type *Value( PhaseTransform *phase ) const;
 327   virtual Node *Identity( PhaseTransform *phase );
 328   virtual uint  ideal_reg() const { return Op_RegF; }
 329 };
 330 
 331 //------------------------------ConvD2INode------------------------------------
 332 // Convert Double to Integer
 333 class ConvD2INode : public Node {
 334 public:
 335   ConvD2INode( Node *in1 ) : Node(0,in1) {}
 336   virtual int Opcode() const;
 337   virtual const Type *bottom_type() const { return TypeInt::INT; }
 338   virtual const Type *Value( PhaseTransform *phase ) const;
 339   virtual Node *Identity( PhaseTransform *phase );
 340   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 341   virtual uint  ideal_reg() const { return Op_RegI; }
 342 };
 343 
 344 //------------------------------ConvD2LNode------------------------------------
 345 // Convert Double to Long
 346 class ConvD2LNode : public Node {
 347 public:
 348   ConvD2LNode( Node *dbl ) : Node(0,dbl) {}
 349   virtual int Opcode() const;
 350   virtual const Type *bottom_type() const { return TypeLong::LONG; }
 351   virtual const Type *Value( PhaseTransform *phase ) const;
 352   virtual Node *Identity( PhaseTransform *phase );
 353   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 354   virtual uint ideal_reg() const { return Op_RegL; }
 355 };
 356 
 357 //------------------------------ConvF2DNode------------------------------------
 358 // Convert Float to a Double.
 359 class ConvF2DNode : public Node {
 360 public:
 361   ConvF2DNode( Node *in1 ) : Node(0,in1) {}
 362   virtual int Opcode() const;
 363   virtual const Type *bottom_type() const { return Type::DOUBLE; }
 364   virtual const Type *Value( PhaseTransform *phase ) const;
 365   virtual uint  ideal_reg() const { return Op_RegD; }
 366 };
 367 
 368 //------------------------------ConvF2INode------------------------------------
 369 // Convert float to integer
 370 class ConvF2INode : public Node {
 371 public:
 372   ConvF2INode( Node *in1 ) : Node(0,in1) {}
 373   virtual int Opcode() const;
 374   virtual const Type *bottom_type() const { return TypeInt::INT; }
 375   virtual const Type *Value( PhaseTransform *phase ) const;
 376   virtual Node *Identity( PhaseTransform *phase );
 377   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 378   virtual uint  ideal_reg() const { return Op_RegI; }
 379 };
 380 
 381 //------------------------------ConvF2LNode------------------------------------
 382 // Convert float to long
 383 class ConvF2LNode : public Node {
 384 public:
 385   ConvF2LNode( Node *in1 ) : Node(0,in1) {}
 386   virtual int Opcode() const;
 387   virtual const Type *bottom_type() const { return TypeLong::LONG; }
 388   virtual const Type *Value( PhaseTransform *phase ) const;
 389   virtual Node *Identity( PhaseTransform *phase );
 390   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 391   virtual uint  ideal_reg() const { return Op_RegL; }
 392 };
 393 
 394 //------------------------------ConvI2DNode------------------------------------
 395 // Convert Integer to Double
 396 class ConvI2DNode : public Node {
 397 public:
 398   ConvI2DNode( Node *in1 ) : Node(0,in1) {}
 399   virtual int Opcode() const;
 400   virtual const Type *bottom_type() const { return Type::DOUBLE; }
 401   virtual const Type *Value( PhaseTransform *phase ) const;
 402   virtual uint  ideal_reg() const { return Op_RegD; }
 403 };
 404 
 405 //------------------------------ConvI2FNode------------------------------------
 406 // Convert Integer to Float
 407 class ConvI2FNode : public Node {
 408 public:
 409   ConvI2FNode( Node *in1 ) : Node(0,in1) {}
 410   virtual int Opcode() const;
 411   virtual const Type *bottom_type() const { return Type::FLOAT; }
 412   virtual const Type *Value( PhaseTransform *phase ) const;
 413   virtual Node *Identity( PhaseTransform *phase );
 414   virtual uint  ideal_reg() const { return Op_RegF; }
 415 };
 416 
 417 //------------------------------ConvI2LNode------------------------------------
 418 // Convert integer to long
 419 class ConvI2LNode : public TypeNode {
 420 public:
 421   ConvI2LNode(Node *in1, const TypeLong* t = TypeLong::INT)
 422     : TypeNode(t, 2)
 423   { init_req(1, in1); }
 424   virtual int Opcode() const;
 425   virtual const Type *Value( PhaseTransform *phase ) const;
 426   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 427   virtual uint  ideal_reg() const { return Op_RegL; }
 428 };
 429 
 430 //------------------------------ConvL2DNode------------------------------------
 431 // Convert Long to Double
 432 class ConvL2DNode : public Node {
 433 public:
 434   ConvL2DNode( Node *in1 ) : Node(0,in1) {}
 435   virtual int Opcode() const;
 436   virtual const Type *bottom_type() const { return Type::DOUBLE; }
 437   virtual const Type *Value( PhaseTransform *phase ) const;
 438   virtual uint ideal_reg() const { return Op_RegD; }
 439 };
 440 
 441 //------------------------------ConvL2FNode------------------------------------
 442 // Convert Long to Float
 443 class ConvL2FNode : public Node {
 444 public:
 445   ConvL2FNode( Node *in1 ) : Node(0,in1) {}
 446   virtual int Opcode() const;
 447   virtual const Type *bottom_type() const { return Type::FLOAT; }
 448   virtual const Type *Value( PhaseTransform *phase ) const;
 449   virtual uint  ideal_reg() const { return Op_RegF; }
 450 };
 451 
 452 //------------------------------ConvL2INode------------------------------------
 453 // Convert long to integer
 454 class ConvL2INode : public Node {
 455 public:
 456   ConvL2INode( Node *in1 ) : Node(0,in1) {}
 457   virtual int Opcode() const;
 458   virtual const Type *bottom_type() const { return TypeInt::INT; }
 459   virtual Node *Identity( PhaseTransform *phase );
 460   virtual const Type *Value( PhaseTransform *phase ) const;
 461   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 462   virtual uint  ideal_reg() const { return Op_RegI; }
 463 };
 464 
 465 //------------------------------CastX2PNode-------------------------------------
 466 // convert a machine-pointer-sized integer to a raw pointer
 467 class CastX2PNode : public Node {
 468 public:
 469   CastX2PNode( Node *n ) : Node(NULL, n) {}
 470   virtual int Opcode() const;
 471   virtual const Type *Value( PhaseTransform *phase ) const;
 472   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 473   virtual Node *Identity( PhaseTransform *phase );
 474   virtual uint ideal_reg() const { return Op_RegP; }
 475   virtual const Type *bottom_type() const { return TypeRawPtr::BOTTOM; }
 476 };
 477 
 478 //------------------------------CastP2XNode-------------------------------------
 479 // Used in both 32-bit and 64-bit land.
 480 // Used for card-marks and unsafe pointer math.
 481 class CastP2XNode : public Node {
 482 public:
 483   CastP2XNode( Node *ctrl, Node *n ) : Node(ctrl, n) {}
 484   virtual int Opcode() const;
 485   virtual const Type *Value( PhaseTransform *phase ) const;
 486   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
 487   virtual Node *Identity( PhaseTransform *phase );
 488   virtual uint ideal_reg() const { return Op_RegX; }
 489   virtual const Type *bottom_type() const { return TypeX_X; }
 490   // Return false to keep node from moving away from an associated card mark.
 491   virtual bool depends_only_on_test() const { return false; }
 492 };
 493 
 494 //------------------------------MemMoveNode------------------------------------
 495 // Memory to memory move.  Inserted very late, after allocation.
 496 class MemMoveNode : public Node {
 497 public:
 498   MemMoveNode( Node *dst, Node *src ) : Node(0,dst,src) {}
 499   virtual int Opcode() const;
 500 };
 501 
 502 //------------------------------ThreadLocalNode--------------------------------
 503 // Ideal Node which returns the base of ThreadLocalStorage.
 504 class ThreadLocalNode : public Node {
 505 public:
 506   ThreadLocalNode( ) : Node((Node*)Compile::current()->root()) {}
 507   virtual int Opcode() const;
 508   virtual const Type *bottom_type() const { return TypeRawPtr::BOTTOM;}
 509   virtual uint ideal_reg() const { return Op_RegP; }
 510 };
 511 
 512 //------------------------------LoadReturnPCNode-------------------------------
 513 class LoadReturnPCNode: public Node {
 514 public:
 515   LoadReturnPCNode(Node *c) : Node(c) { }
 516   virtual int Opcode() const;
 517   virtual uint ideal_reg() const { return Op_RegP; }
 518 };
 519 
 520 
 521 //-----------------------------RoundFloatNode----------------------------------
 522 class RoundFloatNode: public Node {
 523 public:
 524   RoundFloatNode(Node* c, Node *in1): Node(c, in1) {}
 525   virtual int   Opcode() const;
 526   virtual const Type *bottom_type() const { return Type::FLOAT; }
 527   virtual uint  ideal_reg() const { return Op_RegF; }
 528   virtual Node *Identity( PhaseTransform *phase );
 529   virtual const Type *Value( PhaseTransform *phase ) const;
 530 };
 531 
 532 
 533 //-----------------------------RoundDoubleNode---------------------------------
 534 class RoundDoubleNode: public Node {
 535 public:
 536   RoundDoubleNode(Node* c, Node *in1): Node(c, in1) {}
 537   virtual int   Opcode() const;
 538   virtual const Type *bottom_type() const { return Type::DOUBLE; }
 539   virtual uint  ideal_reg() const { return Op_RegD; }
 540   virtual Node *Identity( PhaseTransform *phase );
 541   virtual const Type *Value( PhaseTransform *phase ) const;
 542 };
 543 
 544 //------------------------------Opaque1Node------------------------------------
 545 // A node to prevent unwanted optimizations.  Allows constant folding.
 546 // Stops value-numbering, Ideal calls or Identity functions.
 547 class Opaque1Node : public Node {
 548   virtual uint hash() const ;                  // { return NO_HASH; }
 549   virtual uint cmp( const Node &n ) const;
 550 public:
 551   Opaque1Node( Node *n ) : Node(0,n) {}
 552   // Special version for the pre-loop to hold the original loop limit
 553   // which is consumed by range check elimination.
 554   Opaque1Node( Node *n, Node* orig_limit ) : Node(0,n,orig_limit) {}
 555   Node* original_loop_limit() { return req()==3 ? in(2) : NULL; }
 556   virtual int Opcode() const;
 557   virtual const Type *bottom_type() const { return TypeInt::INT; }
 558   virtual Node *Identity( PhaseTransform *phase );
 559 };
 560 
 561 //------------------------------Opaque2Node------------------------------------
 562 // A node to prevent unwanted optimizations.  Allows constant folding.  Stops
 563 // value-numbering, most Ideal calls or Identity functions.  This Node is
 564 // specifically designed to prevent the pre-increment value of a loop trip
 565 // counter from being live out of the bottom of the loop (hence causing the
 566 // pre- and post-increment values both being live and thus requiring an extra
 567 // temp register and an extra move).  If we "accidentally" optimize through
 568 // this kind of a Node, we'll get slightly pessimal, but correct, code.  Thus
 569 // it's OK to be slightly sloppy on optimizations here.
 570 class Opaque2Node : public Node {
 571   virtual uint hash() const ;                  // { return NO_HASH; }
 572   virtual uint cmp( const Node &n ) const;
 573 public:
 574   Opaque2Node( Node *n ) : Node(0,n) {}
 575   virtual int Opcode() const;
 576   virtual const Type *bottom_type() const { return TypeInt::INT; }
 577 };
 578 
 579 //----------------------PartialSubtypeCheckNode--------------------------------
 580 // The 2nd slow-half of a subtype check.  Scan the subklass's 2ndary superklass
 581 // array for an instance of the superklass.  Set a hidden internal cache on a
 582 // hit (cache is checked with exposed code in gen_subtype_check()).  Return
 583 // not zero for a miss or zero for a hit.
 584 class PartialSubtypeCheckNode : public Node {
 585 public:
 586   PartialSubtypeCheckNode(Node* c, Node* sub, Node* super) : Node(c,sub,super) {}
 587   virtual int Opcode() const;
 588   virtual const Type *bottom_type() const { return TypeRawPtr::BOTTOM; }
 589   virtual uint ideal_reg() const { return Op_RegP; }
 590 };
 591 
 592 //
 593 class MoveI2FNode : public Node {
 594  public:
 595   MoveI2FNode( Node *value ) : Node(0,value) {}
 596   virtual int Opcode() const;
 597   virtual const Type *bottom_type() const { return Type::FLOAT; }
 598   virtual uint ideal_reg() const { return Op_RegF; }
 599   virtual const Type* Value( PhaseTransform *phase ) const;
 600 };
 601 
 602 class MoveL2DNode : public Node {
 603  public:
 604   MoveL2DNode( Node *value ) : Node(0,value) {}
 605   virtual int Opcode() const;
 606   virtual const Type *bottom_type() const { return Type::DOUBLE; }
 607   virtual uint ideal_reg() const { return Op_RegD; }
 608   virtual const Type* Value( PhaseTransform *phase ) const;
 609 };
 610 
 611 class MoveF2INode : public Node {
 612  public:
 613   MoveF2INode( Node *value ) : Node(0,value) {}
 614   virtual int Opcode() const;
 615   virtual const Type *bottom_type() const { return TypeInt::INT; }
 616   virtual uint ideal_reg() const { return Op_RegI; }
 617   virtual const Type* Value( PhaseTransform *phase ) const;
 618 };
 619 
 620 class MoveD2LNode : public Node {
 621  public:
 622   MoveD2LNode( Node *value ) : Node(0,value) {}
 623   virtual int Opcode() const;
 624   virtual const Type *bottom_type() const { return TypeLong::LONG; }
 625   virtual uint ideal_reg() const { return Op_RegL; }
 626   virtual const Type* Value( PhaseTransform *phase ) const;
 627 };