SelectionDAGNodes.h revision b18a2f816cc9d1351ca8e380a6db5c5ef981943e
1//===-- llvm/CodeGen/SelectionDAGNodes.h - SelectionDAG Nodes ---*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file was developed by the LLVM research group and is distributed under 6// the University of Illinois Open Source License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file declares the SDNode class and derived classes, which are used to 11// represent the nodes and operations present in a SelectionDAG. These nodes 12// and operations are machine code level operations, with some similarities to 13// the GCC RTL representation. 14// 15// Clients should include the SelectionDAG.h file instead of this file directly. 16// 17//===----------------------------------------------------------------------===// 18 19#ifndef LLVM_CODEGEN_SELECTIONDAGNODES_H 20#define LLVM_CODEGEN_SELECTIONDAGNODES_H 21 22#include "llvm/CodeGen/ValueTypes.h" 23#include "llvm/ADT/GraphTraits.h" 24#include "llvm/ADT/GraphTraits.h" 25#include "llvm/ADT/iterator" 26#include "llvm/Support/DataTypes.h" 27#include <cassert> 28#include <vector> 29 30namespace llvm { 31 32class SelectionDAG; 33class GlobalValue; 34class MachineBasicBlock; 35class SDNode; 36template <typename T> struct simplify_type; 37 38/// ISD namespace - This namespace contains an enum which represents all of the 39/// SelectionDAG node types and value types. 40/// 41namespace ISD { 42 //===--------------------------------------------------------------------===// 43 /// ISD::NodeType enum - This enum defines all of the operators valid in a 44 /// SelectionDAG. 45 /// 46 enum NodeType { 47 // Leaf nodes 48 EntryToken, Constant, ConstantFP, GlobalAddress, FrameIndex, ConstantPool, 49 BasicBlock, ExternalSymbol, 50 51 // CopyToReg - This node has chain and child nodes, and an associated 52 // register number. The instruction selector must guarantee that the value 53 // of the value node is available in the register stored in the 54 // CopyRegSDNode object. 55 CopyToReg, 56 57 // CopyFromReg - This node indicates that the input value is a virtual or 58 // physical register that is defined outside of the scope of this 59 // SelectionDAG. The register number is available from the CopyRegSDNode 60 // object. 61 CopyFromReg, 62 63 // EXTRACT_ELEMENT - This is used to get the first or second (determined by 64 // a Constant, which is required to be operand #1), element of the aggregate 65 // value specified as operand #0. This is only for use before legalization, 66 // for values that will be broken into multiple registers. 67 EXTRACT_ELEMENT, 68 69 // BUILD_PAIR - This is the opposite of EXTRACT_ELEMENT in some ways. Given 70 // two values of the same integer value type, this produces a value twice as 71 // big. Like EXTRACT_ELEMENT, this can only be used before legalization. 72 BUILD_PAIR, 73 74 75 // Simple binary arithmetic operators. 76 ADD, SUB, MUL, SDIV, UDIV, SREM, UREM, 77 78 // Bitwise operators. 79 AND, OR, XOR, SHL, SRA, SRL, 80 81 // Select operator. 82 SELECT, 83 84 // SetCC operator - This evaluates to a boolean (i1) true value if the 85 // condition is true. These nodes are instances of the 86 // SetCCSDNode class, which contains the condition code as extra 87 // state. 88 SETCC, 89 90 // addc - Three input, two output operator: (X, Y, C) -> (X+Y+C, 91 // Cout). X,Y are integer inputs of agreeing size, C is a one bit 92 // value, and two values are produced: the sum and a carry out. 93 ADDC, SUBB, 94 95 // Conversion operators. These are all single input single output 96 // operations. For all of these, the result type must be strictly 97 // wider or narrower (depending on the operation) than the source 98 // type. 99 100 // SIGN_EXTEND - Used for integer types, replicating the sign bit 101 // into new bits. 102 SIGN_EXTEND, 103 104 // ZERO_EXTEND - Used for integer types, zeroing the new bits. 105 ZERO_EXTEND, 106 107 // TRUNCATE - Completely drop the high bits. 108 TRUNCATE, 109 110 // [SU]INT_TO_FP - These operators convert integers (whose interpreted sign 111 // depends on the first letter) to floating point. 112 SINT_TO_FP, 113 UINT_TO_FP, 114 115 // FP_TO_[US]INT - Convert a floating point value to a signed or unsigned 116 // integer. 117 FP_TO_SINT, 118 FP_TO_UINT, 119 120 // FP_ROUND - Perform a rounding operation from the current 121 // precision down to the specified precision. 122 FP_ROUND, 123 124 // FP_EXTEND - Extend a smaller FP type into a larger FP type. 125 FP_EXTEND, 126 127 // Other operators. LOAD and STORE have token chains. 128 LOAD, STORE, 129 130 // DYNAMIC_STACKALLOC - Allocate some number of bytes on the stack aligned 131 // to a specified boundary. The first operand is the token chain, the 132 // second is the number of bytes to allocate, and the third is the alignment 133 // boundary. 134 DYNAMIC_STACKALLOC, 135 136 // Control flow instructions. These all have token chains. 137 138 // BR - Unconditional branch. The first operand is the chain 139 // operand, the second is the MBB to branch to. 140 BR, 141 142 // BRCOND - Conditional branch. The first operand is the chain, 143 // the second is the condition, the third is the block to branch 144 // to if the condition is true. 145 BRCOND, 146 147 // RET - Return from function. The first operand is the chain, 148 // and any subsequent operands are the return values for the 149 // function. This operation can have variable number of operands. 150 RET, 151 152 // CALL - Call to a function pointer. The first operand is the chain, the 153 // second is the destination function pointer (a GlobalAddress for a direct 154 // call). Arguments have already been lowered to explicit DAGs according to 155 // the calling convention in effect here. 156 CALL, 157 158 // MEMSET/MEMCPY/MEMMOVE - The first operand is the chain, and the rest 159 // correspond to the operands of the LLVM intrinsic functions. The only 160 // result is a token chain. The alignment argument is guaranteed to be a 161 // Constant node. 162 MEMSET, 163 MEMMOVE, 164 MEMCPY, 165 166 // ADJCALLSTACKDOWN/ADJCALLSTACKUP - These operators mark the beginning and 167 // end of a call sequence and indicate how much the stack pointer needs to 168 // be adjusted for that particular call. The first operand is a chain, the 169 // second is a ConstantSDNode of intptr type. 170 ADJCALLSTACKDOWN, // Beginning of a call sequence 171 ADJCALLSTACKUP, // End of a call sequence 172 173 174 // BUILTIN_OP_END - This must be the last enum value in this list. 175 BUILTIN_OP_END, 176 }; 177 178 //===--------------------------------------------------------------------===// 179 /// ISD::CondCode enum - These are ordered carefully to make the bitfields 180 /// below work out, when considering SETFALSE (something that never exists 181 /// dynamically) as 0. "U" -> Unsigned (for integer operands) or Unordered 182 /// (for floating point), "L" -> Less than, "G" -> Greater than, "E" -> Equal 183 /// to. If the "N" column is 1, the result of the comparison is undefined if 184 /// the input is a NAN. 185 /// 186 /// All of these (except for the 'always folded ops') should be handled for 187 /// floating point. For integer, only the SETEQ,SETNE,SETLT,SETLE,SETGT, 188 /// SETGE,SETULT,SETULE,SETUGT, and SETUGE opcodes are used. 189 /// 190 /// Note that these are laid out in a specific order to allow bit-twiddling 191 /// to transform conditions. 192 enum CondCode { 193 // Opcode N U L G E Intuitive operation 194 SETFALSE, // 0 0 0 0 Always false (always folded) 195 SETOEQ, // 0 0 0 1 True if ordered and equal 196 SETOGT, // 0 0 1 0 True if ordered and greater than 197 SETOGE, // 0 0 1 1 True if ordered and greater than or equal 198 SETOLT, // 0 1 0 0 True if ordered and less than 199 SETOLE, // 0 1 0 1 True if ordered and less than or equal 200 SETONE, // 0 1 1 0 True if ordered and operands are unequal 201 SETO, // 0 1 1 1 True if ordered (no nans) 202 SETUO, // 1 0 0 0 True if unordered: isnan(X) | isnan(Y) 203 SETUEQ, // 1 0 0 1 True if unordered or equal 204 SETUGT, // 1 0 1 0 True if unordered or greater than 205 SETUGE, // 1 0 1 1 True if unordered, greater than, or equal 206 SETULT, // 1 1 0 0 True if unordered or less than 207 SETULE, // 1 1 0 1 True if unordered, less than, or equal 208 SETUNE, // 1 1 1 0 True if unordered or not equal 209 SETTRUE, // 1 1 1 1 Always true (always folded) 210 // Don't care operations: undefined if the input is a nan. 211 SETFALSE2, // 1 X 0 0 0 Always false (always folded) 212 SETEQ, // 1 X 0 0 1 True if equal 213 SETGT, // 1 X 0 1 0 True if greater than 214 SETGE, // 1 X 0 1 1 True if greater than or equal 215 SETLT, // 1 X 1 0 0 True if less than 216 SETLE, // 1 X 1 0 1 True if less than or equal 217 SETNE, // 1 X 1 1 0 True if not equal 218 SETTRUE2, // 1 X 1 1 1 Always true (always folded) 219 220 SETCC_INVALID, // Marker value. 221 }; 222 223 /// isSignedIntSetCC - Return true if this is a setcc instruction that 224 /// performs a signed comparison when used with integer operands. 225 inline bool isSignedIntSetCC(CondCode Code) { 226 return Code == SETGT || Code == SETGE || Code == SETLT || Code == SETLE; 227 } 228 229 /// isUnsignedIntSetCC - Return true if this is a setcc instruction that 230 /// performs an unsigned comparison when used with integer operands. 231 inline bool isUnsignedIntSetCC(CondCode Code) { 232 return Code == SETUGT || Code == SETUGE || Code == SETULT || Code == SETULE; 233 } 234 235 /// isTrueWhenEqual - Return true if the specified condition returns true if 236 /// the two operands to the condition are equal. Note that if one of the two 237 /// operands is a NaN, this value is meaningless. 238 inline bool isTrueWhenEqual(CondCode Cond) { 239 return ((int)Cond & 1) != 0; 240 } 241 242 /// getUnorderedFlavor - This function returns 0 if the condition is always 243 /// false if an operand is a NaN, 1 if the condition is always true if the 244 /// operand is a NaN, and 2 if the condition is undefined if the operand is a 245 /// NaN. 246 inline unsigned getUnorderedFlavor(CondCode Cond) { 247 return ((int)Cond >> 3) & 3; 248 } 249 250 /// getSetCCInverse - Return the operation corresponding to !(X op Y), where 251 /// 'op' is a valid SetCC operation. 252 CondCode getSetCCInverse(CondCode Operation, bool isInteger); 253 254 /// getSetCCSwappedOperands - Return the operation corresponding to (Y op X) 255 /// when given the operation for (X op Y). 256 CondCode getSetCCSwappedOperands(CondCode Operation); 257 258 /// getSetCCOrOperation - Return the result of a logical OR between different 259 /// comparisons of identical values: ((X op1 Y) | (X op2 Y)). This 260 /// function returns SETCC_INVALID if it is not possible to represent the 261 /// resultant comparison. 262 CondCode getSetCCOrOperation(CondCode Op1, CondCode Op2, bool isInteger); 263 264 /// getSetCCAndOperation - Return the result of a logical AND between 265 /// different comparisons of identical values: ((X op1 Y) & (X op2 Y)). This 266 /// function returns SETCC_INVALID if it is not possible to represent the 267 /// resultant comparison. 268 CondCode getSetCCAndOperation(CondCode Op1, CondCode Op2, bool isInteger); 269} // end llvm::ISD namespace 270 271 272//===----------------------------------------------------------------------===// 273/// SDOperand - Unlike LLVM values, Selection DAG nodes may return multiple 274/// values as the result of a computation. Many nodes return multiple values, 275/// from loads (which define a token and a return value) to ADDC (which returns 276/// a result and a carry value), to calls (which may return an arbitrary number 277/// of values). 278/// 279/// As such, each use of a SelectionDAG computation must indicate the node that 280/// computes it as well as which return value to use from that node. This pair 281/// of information is represented with the SDOperand value type. 282/// 283class SDOperand { 284public: 285 SDNode *Val; // The node defining the value we are using. 286 unsigned ResNo; // Which return value of the node we are using. 287 288 SDOperand() : Val(0) {} 289 SDOperand(SDNode *val, unsigned resno) : Val(val), ResNo(resno) {} 290 291 bool operator==(const SDOperand &O) const { 292 return Val == O.Val && ResNo == O.ResNo; 293 } 294 bool operator!=(const SDOperand &O) const { 295 return !operator==(O); 296 } 297 bool operator<(const SDOperand &O) const { 298 return Val < O.Val || (Val == O.Val && ResNo < O.ResNo); 299 } 300 301 SDOperand getValue(unsigned R) const { 302 return SDOperand(Val, R); 303 } 304 305 /// getValueType - Return the ValueType of the referenced return value. 306 /// 307 inline MVT::ValueType getValueType() const; 308 309 // Forwarding methods - These forward to the corresponding methods in SDNode. 310 inline unsigned getOpcode() const; 311 inline unsigned getNumOperands() const; 312 inline const SDOperand &getOperand(unsigned i) const; 313}; 314 315 316/// simplify_type specializations - Allow casting operators to work directly on 317/// SDOperands as if they were SDNode*'s. 318template<> struct simplify_type<SDOperand> { 319 typedef SDNode* SimpleType; 320 static SimpleType getSimplifiedValue(const SDOperand &Val) { 321 return static_cast<SimpleType>(Val.Val); 322 } 323}; 324template<> struct simplify_type<const SDOperand> { 325 typedef SDNode* SimpleType; 326 static SimpleType getSimplifiedValue(const SDOperand &Val) { 327 return static_cast<SimpleType>(Val.Val); 328 } 329}; 330 331 332/// SDNode - Represents one node in the SelectionDAG. 333/// 334class SDNode { 335 unsigned NodeType; 336 std::vector<SDOperand> Operands; 337 338 /// Values - The types of the values this node defines. SDNode's may define 339 /// multiple values simultaneously. 340 std::vector<MVT::ValueType> Values; 341 342 /// Uses - These are all of the SDNode's that use a value produced by this 343 /// node. 344 std::vector<SDNode*> Uses; 345public: 346 347 //===--------------------------------------------------------------------===// 348 // Accessors 349 // 350 unsigned getOpcode() const { return NodeType; } 351 352 size_t use_size() const { return Uses.size(); } 353 bool use_empty() const { return Uses.empty(); } 354 bool hasOneUse() const { return Uses.size() == 1; } 355 356 /// hasNUsesOfValue - Return true if there are exactly NUSES uses of the 357 /// indicated value. This method ignores uses of other values defined by this 358 /// operation. 359 bool hasNUsesOfValue(unsigned NUses, unsigned Value); 360 361 /// getNumOperands - Return the number of values used by this operation. 362 /// 363 unsigned getNumOperands() const { return Operands.size(); } 364 365 const SDOperand &getOperand(unsigned Num) { 366 assert(Num < Operands.size() && "Invalid child # of SDNode!"); 367 return Operands[Num]; 368 } 369 370 const SDOperand &getOperand(unsigned Num) const { 371 assert(Num < Operands.size() && "Invalid child # of SDNode!"); 372 return Operands[Num]; 373 } 374 375 /// getNumValues - Return the number of values defined/returned by this 376 /// operator. 377 /// 378 unsigned getNumValues() const { return Values.size(); } 379 380 /// getValueType - Return the type of a specified result. 381 /// 382 MVT::ValueType getValueType(unsigned ResNo) const { 383 assert(ResNo < Values.size() && "Illegal result number!"); 384 return Values[ResNo]; 385 } 386 387 /// getOperationName - Return the opcode of this operation for printing. 388 /// 389 const char* getOperationName() const; 390 void dump() const; 391 392 static bool classof(const SDNode *) { return true; } 393 394protected: 395 friend class SelectionDAG; 396 397 SDNode(unsigned NT, MVT::ValueType VT) : NodeType(NT) { 398 Values.reserve(1); 399 Values.push_back(VT); 400 } 401 402 SDNode(unsigned NT, SDOperand Op) 403 : NodeType(NT) { 404 Operands.reserve(1); Operands.push_back(Op); 405 Op.Val->Uses.push_back(this); 406 } 407 SDNode(unsigned NT, SDOperand N1, SDOperand N2) 408 : NodeType(NT) { 409 Operands.reserve(2); Operands.push_back(N1); Operands.push_back(N2); 410 N1.Val->Uses.push_back(this); N2.Val->Uses.push_back(this); 411 } 412 SDNode(unsigned NT, SDOperand N1, SDOperand N2, SDOperand N3) 413 : NodeType(NT) { 414 Operands.reserve(3); Operands.push_back(N1); Operands.push_back(N2); 415 Operands.push_back(N3); 416 N1.Val->Uses.push_back(this); N2.Val->Uses.push_back(this); 417 N3.Val->Uses.push_back(this); 418 } 419 SDNode(unsigned NT, std::vector<SDOperand> &Nodes) : NodeType(NT) { 420 Operands.swap(Nodes); 421 for (unsigned i = 0, e = Operands.size(); i != e; ++i) 422 Operands[i].Val->Uses.push_back(this); 423 } 424 425 virtual ~SDNode() { 426 // FIXME: Drop uses. 427 } 428 429 void setValueTypes(MVT::ValueType VT) { 430 Values.reserve(1); 431 Values.push_back(VT); 432 } 433 void setValueTypes(MVT::ValueType VT1, MVT::ValueType VT2) { 434 Values.reserve(2); 435 Values.push_back(VT1); 436 Values.push_back(VT2); 437 } 438 /// Note: this method destroys the vector passed in. 439 void setValueTypes(std::vector<MVT::ValueType> &VTs) { 440 std::swap(Values, VTs); 441 } 442 443 void removeUser(SDNode *User) { 444 // Remove this user from the operand's use list. 445 for (unsigned i = Uses.size(); ; --i) { 446 assert(i != 0 && "Didn't find user!"); 447 if (Uses[i-1] == User) { 448 Uses.erase(Uses.begin()+i-1); 449 break; 450 } 451 } 452 } 453}; 454 455 456// Define inline functions from the SDOperand class. 457 458inline unsigned SDOperand::getOpcode() const { 459 return Val->getOpcode(); 460} 461inline MVT::ValueType SDOperand::getValueType() const { 462 return Val->getValueType(ResNo); 463} 464inline unsigned SDOperand::getNumOperands() const { 465 return Val->getNumOperands(); 466} 467inline const SDOperand &SDOperand::getOperand(unsigned i) const { 468 return Val->getOperand(i); 469} 470 471 472 473class ConstantSDNode : public SDNode { 474 uint64_t Value; 475protected: 476 friend class SelectionDAG; 477 ConstantSDNode(uint64_t val, MVT::ValueType VT) 478 : SDNode(ISD::Constant, VT), Value(val) { 479 } 480public: 481 482 uint64_t getValue() const { return Value; } 483 484 int64_t getSignExtended() const { 485 unsigned Bits = MVT::getSizeInBits(getValueType(0)); 486 return ((int64_t)Value << (64-Bits)) >> (64-Bits); 487 } 488 489 bool isNullValue() const { return Value == 0; } 490 bool isAllOnesValue() const { 491 return Value == (1ULL << MVT::getSizeInBits(getValueType(0)))-1; 492 } 493 494 static bool classof(const ConstantSDNode *) { return true; } 495 static bool classof(const SDNode *N) { 496 return N->getOpcode() == ISD::Constant; 497 } 498}; 499 500class ConstantFPSDNode : public SDNode { 501 double Value; 502protected: 503 friend class SelectionDAG; 504 ConstantFPSDNode(double val, MVT::ValueType VT) 505 : SDNode(ISD::ConstantFP, VT), Value(val) { 506 } 507public: 508 509 double getValue() const { return Value; } 510 511 /// isExactlyValue - We don't rely on operator== working on double values, as 512 /// it returns true for things that are clearly not equal, like -0.0 and 0.0. 513 /// As such, this method can be used to do an exact bit-for-bit comparison of 514 /// two floating point values. 515 bool isExactlyValue(double V) const { 516 union { 517 double V; 518 uint64_t I; 519 } T1; 520 T1.V = Value; 521 union { 522 double V; 523 uint64_t I; 524 } T2; 525 T2.V = V; 526 return T1.I == T2.I; 527 } 528 529 static bool classof(const ConstantFPSDNode *) { return true; } 530 static bool classof(const SDNode *N) { 531 return N->getOpcode() == ISD::ConstantFP; 532 } 533}; 534 535class GlobalAddressSDNode : public SDNode { 536 GlobalValue *TheGlobal; 537protected: 538 friend class SelectionDAG; 539 GlobalAddressSDNode(const GlobalValue *GA, MVT::ValueType VT) 540 : SDNode(ISD::GlobalAddress, VT) { 541 TheGlobal = const_cast<GlobalValue*>(GA); 542 } 543public: 544 545 GlobalValue *getGlobal() const { return TheGlobal; } 546 547 static bool classof(const GlobalAddressSDNode *) { return true; } 548 static bool classof(const SDNode *N) { 549 return N->getOpcode() == ISD::GlobalAddress; 550 } 551}; 552 553 554class FrameIndexSDNode : public SDNode { 555 int FI; 556protected: 557 friend class SelectionDAG; 558 FrameIndexSDNode(int fi, MVT::ValueType VT) 559 : SDNode(ISD::FrameIndex, VT), FI(fi) {} 560public: 561 562 int getIndex() const { return FI; } 563 564 static bool classof(const FrameIndexSDNode *) { return true; } 565 static bool classof(const SDNode *N) { 566 return N->getOpcode() == ISD::FrameIndex; 567 } 568}; 569 570class ConstantPoolSDNode : public SDNode { 571 unsigned CPI; 572protected: 573 friend class SelectionDAG; 574 ConstantPoolSDNode(unsigned cpi, MVT::ValueType VT) 575 : SDNode(ISD::ConstantPool, VT), CPI(cpi) {} 576public: 577 578 unsigned getIndex() const { return CPI; } 579 580 static bool classof(const ConstantPoolSDNode *) { return true; } 581 static bool classof(const SDNode *N) { 582 return N->getOpcode() == ISD::ConstantPool; 583 } 584}; 585 586class BasicBlockSDNode : public SDNode { 587 MachineBasicBlock *MBB; 588protected: 589 friend class SelectionDAG; 590 BasicBlockSDNode(MachineBasicBlock *mbb) 591 : SDNode(ISD::BasicBlock, MVT::Other), MBB(mbb) {} 592public: 593 594 MachineBasicBlock *getBasicBlock() const { return MBB; } 595 596 static bool classof(const BasicBlockSDNode *) { return true; } 597 static bool classof(const SDNode *N) { 598 return N->getOpcode() == ISD::BasicBlock; 599 } 600}; 601 602 603class CopyRegSDNode : public SDNode { 604 unsigned Reg; 605protected: 606 friend class SelectionDAG; 607 CopyRegSDNode(SDOperand Chain, SDOperand Src, unsigned reg) 608 : SDNode(ISD::CopyToReg, Chain, Src), Reg(reg) { 609 setValueTypes(MVT::Other); // Just a token chain. 610 } 611 CopyRegSDNode(unsigned reg, MVT::ValueType VT) 612 : SDNode(ISD::CopyFromReg, VT), Reg(reg) { 613 } 614public: 615 616 unsigned getReg() const { return Reg; } 617 618 static bool classof(const CopyRegSDNode *) { return true; } 619 static bool classof(const SDNode *N) { 620 return N->getOpcode() == ISD::CopyToReg || 621 N->getOpcode() == ISD::CopyFromReg; 622 } 623}; 624 625class ExternalSymbolSDNode : public SDNode { 626 const char *Symbol; 627protected: 628 friend class SelectionDAG; 629 ExternalSymbolSDNode(const char *Sym, MVT::ValueType VT) 630 : SDNode(ISD::ExternalSymbol, VT), Symbol(Sym) { 631 } 632public: 633 634 const char *getSymbol() const { return Symbol; } 635 636 static bool classof(const ExternalSymbolSDNode *) { return true; } 637 static bool classof(const SDNode *N) { 638 return N->getOpcode() == ISD::ExternalSymbol; 639 } 640}; 641 642class SetCCSDNode : public SDNode { 643 ISD::CondCode Condition; 644protected: 645 friend class SelectionDAG; 646 SetCCSDNode(ISD::CondCode Cond, SDOperand LHS, SDOperand RHS) 647 : SDNode(ISD::SETCC, LHS, RHS), Condition(Cond) { 648 setValueTypes(MVT::i1); 649 } 650public: 651 652 ISD::CondCode getCondition() const { return Condition; } 653 654 static bool classof(const SetCCSDNode *) { return true; } 655 static bool classof(const SDNode *N) { 656 return N->getOpcode() == ISD::SETCC; 657 } 658}; 659 660 661class SDNodeIterator : public forward_iterator<SDNode, ptrdiff_t> { 662 SDNode *Node; 663 unsigned Operand; 664 665 SDNodeIterator(SDNode *N, unsigned Op) : Node(N), Operand(Op) {} 666public: 667 bool operator==(const SDNodeIterator& x) const { 668 return Operand == x.Operand; 669 } 670 bool operator!=(const SDNodeIterator& x) const { return !operator==(x); } 671 672 const SDNodeIterator &operator=(const SDNodeIterator &I) { 673 assert(I.Node == Node && "Cannot assign iterators to two different nodes!"); 674 Operand = I.Operand; 675 return *this; 676 } 677 678 pointer operator*() const { 679 return Node->getOperand(Operand).Val; 680 } 681 pointer operator->() const { return operator*(); } 682 683 SDNodeIterator& operator++() { // Preincrement 684 ++Operand; 685 return *this; 686 } 687 SDNodeIterator operator++(int) { // Postincrement 688 SDNodeIterator tmp = *this; ++*this; return tmp; 689 } 690 691 static SDNodeIterator begin(SDNode *N) { return SDNodeIterator(N, 0); } 692 static SDNodeIterator end (SDNode *N) { 693 return SDNodeIterator(N, N->getNumOperands()); 694 } 695 696 unsigned getOperand() const { return Operand; } 697 const SDNode *getNode() const { return Node; } 698}; 699 700template <> struct GraphTraits<SDNode*> { 701 typedef SDNode NodeType; 702 typedef SDNodeIterator ChildIteratorType; 703 static inline NodeType *getEntryNode(SDNode *N) { return N; } 704 static inline ChildIteratorType child_begin(NodeType *N) { 705 return SDNodeIterator::begin(N); 706 } 707 static inline ChildIteratorType child_end(NodeType *N) { 708 return SDNodeIterator::end(N); 709 } 710}; 711 712 713 714 715} // end llvm namespace 716 717#endif 718