SelectionDAG.h revision df0c7bc52d206782872b54a38a3374f0317ce6ff
1//===-- llvm/CodeGen/SelectionDAG.h - InstSelection DAG ---------*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file declares the SelectionDAG class, and transitively defines the 11// SDNode class and subclasses. 12// 13//===----------------------------------------------------------------------===// 14 15#ifndef LLVM_CODEGEN_SELECTIONDAG_H 16#define LLVM_CODEGEN_SELECTIONDAG_H 17 18#include "llvm/ADT/ilist.h" 19#include "llvm/ADT/FoldingSet.h" 20#include "llvm/ADT/StringMap.h" 21#include "llvm/CodeGen/SelectionDAGNodes.h" 22 23#include <cassert> 24#include <list> 25#include <vector> 26#include <map> 27#include <string> 28 29namespace llvm { 30 31class AliasAnalysis; 32class TargetLowering; 33class TargetMachine; 34class MachineModuleInfo; 35class MachineFunction; 36class MachineConstantPoolValue; 37class FunctionLoweringInfo; 38 39template<> struct ilist_traits<SDNode> : public ilist_default_traits<SDNode> { 40private: 41 mutable SDNode Sentinel; 42public: 43 ilist_traits() : Sentinel(ISD::DELETED_NODE, SDVTList()) {} 44 45 SDNode *createSentinel() const { 46 return &Sentinel; 47 } 48 static void destroySentinel(SDNode *) {} 49 50 static void deleteNode(SDNode *) { 51 assert(0 && "ilist_traits<SDNode> shouldn't see a deleteNode call!"); 52 } 53private: 54 static void createNode(const SDNode &); 55}; 56 57/// SelectionDAG class - This is used to represent a portion of an LLVM function 58/// in a low-level Data Dependence DAG representation suitable for instruction 59/// selection. This DAG is constructed as the first step of instruction 60/// selection in order to allow implementation of machine specific optimizations 61/// and code simplifications. 62/// 63/// The representation used by the SelectionDAG is a target-independent 64/// representation, which has some similarities to the GCC RTL representation, 65/// but is significantly more simple, powerful, and is a graph form instead of a 66/// linear form. 67/// 68class SelectionDAG { 69 TargetLowering &TLI; 70 MachineFunction *MF; 71 FunctionLoweringInfo &FLI; 72 MachineModuleInfo *MMI; 73 74 /// EntryNode - The starting token. 75 SDNode EntryNode; 76 77 /// Root - The root of the entire DAG. 78 SDValue Root; 79 80 /// AllNodes - A linked list of nodes in the current DAG. 81 ilist<SDNode> AllNodes; 82 83 /// NodeAllocatorType - The AllocatorType for allocating SDNodes. We use 84 /// pool allocation with recycling. 85 typedef RecyclingAllocator<BumpPtrAllocator, SDNode, sizeof(LargestSDNode), 86 AlignOf<MostAlignedSDNode>::Alignment> 87 NodeAllocatorType; 88 89 /// NodeAllocator - Pool allocation for nodes. 90 NodeAllocatorType NodeAllocator; 91 92 /// CSEMap - This structure is used to memoize nodes, automatically performing 93 /// CSE with existing nodes with a duplicate is requested. 94 FoldingSet<SDNode> CSEMap; 95 96 /// OperandAllocator - Pool allocation for machine-opcode SDNode operands. 97 BumpPtrAllocator OperandAllocator; 98 99 /// Allocator - Pool allocation for misc. objects that are created once per 100 /// SelectionDAG. 101 BumpPtrAllocator Allocator; 102 103 /// VerifyNode - Sanity check the given node. Aborts if it is invalid. 104 void VerifyNode(SDNode *N); 105 106public: 107 SelectionDAG(TargetLowering &tli, FunctionLoweringInfo &fli); 108 ~SelectionDAG(); 109 110 /// init - Prepare this SelectionDAG to process code in the given 111 /// MachineFunction. 112 /// 113 void init(MachineFunction &mf, MachineModuleInfo *mmi); 114 115 /// clear - Clear state and free memory necessary to make this 116 /// SelectionDAG ready to process a new block. 117 /// 118 void clear(); 119 120 MachineFunction &getMachineFunction() const { return *MF; } 121 const TargetMachine &getTarget() const; 122 TargetLowering &getTargetLoweringInfo() const { return TLI; } 123 FunctionLoweringInfo &getFunctionLoweringInfo() const { return FLI; } 124 MachineModuleInfo *getMachineModuleInfo() const { return MMI; } 125 126 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'. 127 /// 128 void viewGraph(const std::string &Title); 129 void viewGraph(); 130 131#ifndef NDEBUG 132 std::map<const SDNode *, std::string> NodeGraphAttrs; 133#endif 134 135 /// clearGraphAttrs - Clear all previously defined node graph attributes. 136 /// Intended to be used from a debugging tool (eg. gdb). 137 void clearGraphAttrs(); 138 139 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".) 140 /// 141 void setGraphAttrs(const SDNode *N, const char *Attrs); 142 143 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".) 144 /// Used from getNodeAttributes. 145 const std::string getGraphAttrs(const SDNode *N) const; 146 147 /// setGraphColor - Convenience for setting node color attribute. 148 /// 149 void setGraphColor(const SDNode *N, const char *Color); 150 151 typedef ilist<SDNode>::const_iterator allnodes_const_iterator; 152 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); } 153 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); } 154 typedef ilist<SDNode>::iterator allnodes_iterator; 155 allnodes_iterator allnodes_begin() { return AllNodes.begin(); } 156 allnodes_iterator allnodes_end() { return AllNodes.end(); } 157 ilist<SDNode>::size_type allnodes_size() const { 158 return AllNodes.size(); 159 } 160 161 /// getRoot - Return the root tag of the SelectionDAG. 162 /// 163 const SDValue &getRoot() const { return Root; } 164 165 /// getEntryNode - Return the token chain corresponding to the entry of the 166 /// function. 167 SDValue getEntryNode() const { 168 return SDValue(const_cast<SDNode *>(&EntryNode), 0); 169 } 170 171 /// setRoot - Set the current root tag of the SelectionDAG. 172 /// 173 const SDValue &setRoot(SDValue N) { 174 assert((!N.getNode() || N.getValueType() == MVT::Other) && 175 "DAG root value is not a chain!"); 176 return Root = N; 177 } 178 179 /// Combine - This iterates over the nodes in the SelectionDAG, folding 180 /// certain types of nodes together, or eliminating superfluous nodes. When 181 /// the AfterLegalize argument is set to 'true', Combine takes care not to 182 /// generate any nodes that will be illegal on the target. 183 void Combine(bool AfterLegalize, AliasAnalysis &AA, bool Fast); 184 185 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that 186 /// only uses types natively supported by the target. 187 /// 188 /// Note that this is an involved process that may invalidate pointers into 189 /// the graph. 190 void LegalizeTypes(); 191 192 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is 193 /// compatible with the target instruction selector, as indicated by the 194 /// TargetLowering object. 195 /// 196 /// Note that this is an involved process that may invalidate pointers into 197 /// the graph. 198 void Legalize(); 199 200 /// RemoveDeadNodes - This method deletes all unreachable nodes in the 201 /// SelectionDAG. 202 void RemoveDeadNodes(); 203 204 /// DeleteNode - Remove the specified node from the system. This node must 205 /// have no referrers. 206 void DeleteNode(SDNode *N); 207 208 /// getVTList - Return an SDVTList that represents the list of values 209 /// specified. 210 SDVTList getVTList(MVT VT); 211 SDVTList getVTList(MVT VT1, MVT VT2); 212 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3); 213 SDVTList getVTList(const MVT *VTs, unsigned NumVTs); 214 215 /// getNodeValueTypes - These are obsolete, use getVTList instead. 216 const MVT *getNodeValueTypes(MVT VT) { 217 return getVTList(VT).VTs; 218 } 219 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) { 220 return getVTList(VT1, VT2).VTs; 221 } 222 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) { 223 return getVTList(VT1, VT2, VT3).VTs; 224 } 225 const MVT *getNodeValueTypes(const std::vector<MVT> &vtList) { 226 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs; 227 } 228 229 230 //===--------------------------------------------------------------------===// 231 // Node creation methods. 232 // 233 SDValue getConstant(uint64_t Val, MVT VT, bool isTarget = false); 234 SDValue getConstant(const APInt &Val, MVT VT, bool isTarget = false); 235 SDValue getConstant(const ConstantInt &Val, MVT VT, bool isTarget = false); 236 SDValue getIntPtrConstant(uint64_t Val, bool isTarget = false); 237 SDValue getTargetConstant(uint64_t Val, MVT VT) { 238 return getConstant(Val, VT, true); 239 } 240 SDValue getTargetConstant(const APInt &Val, MVT VT) { 241 return getConstant(Val, VT, true); 242 } 243 SDValue getTargetConstant(const ConstantInt &Val, MVT VT) { 244 return getConstant(Val, VT, true); 245 } 246 SDValue getConstantFP(double Val, MVT VT, bool isTarget = false); 247 SDValue getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false); 248 SDValue getConstantFP(const ConstantFP &CF, MVT VT, bool isTarget = false); 249 SDValue getTargetConstantFP(double Val, MVT VT) { 250 return getConstantFP(Val, VT, true); 251 } 252 SDValue getTargetConstantFP(const APFloat& Val, MVT VT) { 253 return getConstantFP(Val, VT, true); 254 } 255 SDValue getTargetConstantFP(const ConstantFP &Val, MVT VT) { 256 return getConstantFP(Val, VT, true); 257 } 258 SDValue getGlobalAddress(const GlobalValue *GV, MVT VT, 259 int offset = 0, bool isTargetGA = false); 260 SDValue getTargetGlobalAddress(const GlobalValue *GV, MVT VT, 261 int offset = 0) { 262 return getGlobalAddress(GV, VT, offset, true); 263 } 264 SDValue getFrameIndex(int FI, MVT VT, bool isTarget = false); 265 SDValue getTargetFrameIndex(int FI, MVT VT) { 266 return getFrameIndex(FI, VT, true); 267 } 268 SDValue getJumpTable(int JTI, MVT VT, bool isTarget = false); 269 SDValue getTargetJumpTable(int JTI, MVT VT) { 270 return getJumpTable(JTI, VT, true); 271 } 272 SDValue getConstantPool(Constant *C, MVT VT, 273 unsigned Align = 0, int Offs = 0, bool isT=false); 274 SDValue getTargetConstantPool(Constant *C, MVT VT, 275 unsigned Align = 0, int Offset = 0) { 276 return getConstantPool(C, VT, Align, Offset, true); 277 } 278 SDValue getConstantPool(MachineConstantPoolValue *C, MVT VT, 279 unsigned Align = 0, int Offs = 0, bool isT=false); 280 SDValue getTargetConstantPool(MachineConstantPoolValue *C, 281 MVT VT, unsigned Align = 0, 282 int Offset = 0) { 283 return getConstantPool(C, VT, Align, Offset, true); 284 } 285 SDValue getBasicBlock(MachineBasicBlock *MBB); 286 SDValue getExternalSymbol(const char *Sym, MVT VT); 287 SDValue getTargetExternalSymbol(const char *Sym, MVT VT); 288 SDValue getArgFlags(ISD::ArgFlagsTy Flags); 289 SDValue getValueType(MVT); 290 SDValue getRegister(unsigned Reg, MVT VT); 291 SDValue getDbgStopPoint(SDValue Root, unsigned Line, unsigned Col, 292 const CompileUnitDesc *CU); 293 SDValue getLabel(unsigned Opcode, SDValue Root, unsigned LabelID); 294 295 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N) { 296 return getNode(ISD::CopyToReg, MVT::Other, Chain, 297 getRegister(Reg, N.getValueType()), N); 298 } 299 300 // This version of the getCopyToReg method takes an extra operand, which 301 // indicates that there is potentially an incoming flag value (if Flag is not 302 // null) and that there should be a flag result. 303 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N, 304 SDValue Flag) { 305 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag); 306 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag }; 307 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3); 308 } 309 310 // Similar to last getCopyToReg() except parameter Reg is a SDValue 311 SDValue getCopyToReg(SDValue Chain, SDValue Reg, SDValue N, 312 SDValue Flag) { 313 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag); 314 SDValue Ops[] = { Chain, Reg, N, Flag }; 315 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3); 316 } 317 318 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT) { 319 const MVT *VTs = getNodeValueTypes(VT, MVT::Other); 320 SDValue Ops[] = { Chain, getRegister(Reg, VT) }; 321 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2); 322 } 323 324 // This version of the getCopyFromReg method takes an extra operand, which 325 // indicates that there is potentially an incoming flag value (if Flag is not 326 // null) and that there should be a flag result. 327 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT, 328 SDValue Flag) { 329 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag); 330 SDValue Ops[] = { Chain, getRegister(Reg, VT), Flag }; 331 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.getNode() ? 3 : 2); 332 } 333 334 SDValue getCondCode(ISD::CondCode Cond); 335 336 /// getZeroExtendInReg - Return the expression required to zero extend the Op 337 /// value assuming it was the smaller SrcTy value. 338 SDValue getZeroExtendInReg(SDValue Op, MVT SrcTy); 339 340 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have 341 /// a flag result (to ensure it's not CSE'd). 342 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op) { 343 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag); 344 SDValue Ops[] = { Chain, Op }; 345 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2); 346 } 347 348 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a 349 /// flag result (to ensure it's not CSE'd). 350 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2, 351 SDValue InFlag) { 352 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag); 353 SmallVector<SDValue, 4> Ops; 354 Ops.push_back(Chain); 355 Ops.push_back(Op1); 356 Ops.push_back(Op2); 357 Ops.push_back(InFlag); 358 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0], 359 (unsigned)Ops.size() - (InFlag.getNode() == 0 ? 1 : 0)); 360 } 361 362 /// getNode - Gets or creates the specified node. 363 /// 364 SDValue getNode(unsigned Opcode, MVT VT); 365 SDValue getNode(unsigned Opcode, MVT VT, SDValue N); 366 SDValue getNode(unsigned Opcode, MVT VT, SDValue N1, SDValue N2); 367 SDValue getNode(unsigned Opcode, MVT VT, 368 SDValue N1, SDValue N2, SDValue N3); 369 SDValue getNode(unsigned Opcode, MVT VT, 370 SDValue N1, SDValue N2, SDValue N3, SDValue N4); 371 SDValue getNode(unsigned Opcode, MVT VT, 372 SDValue N1, SDValue N2, SDValue N3, SDValue N4, 373 SDValue N5); 374 SDValue getNode(unsigned Opcode, MVT VT, 375 const SDValue *Ops, unsigned NumOps); 376 SDValue getNode(unsigned Opcode, MVT VT, 377 const SDUse *Ops, unsigned NumOps); 378 SDValue getNode(unsigned Opcode, const std::vector<MVT> &ResultTys, 379 const SDValue *Ops, unsigned NumOps); 380 SDValue getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs, 381 const SDValue *Ops, unsigned NumOps); 382 SDValue getNode(unsigned Opcode, SDVTList VTs); 383 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N); 384 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N1, SDValue N2); 385 SDValue getNode(unsigned Opcode, SDVTList VTs, 386 SDValue N1, SDValue N2, SDValue N3); 387 SDValue getNode(unsigned Opcode, SDVTList VTs, 388 SDValue N1, SDValue N2, SDValue N3, SDValue N4); 389 SDValue getNode(unsigned Opcode, SDVTList VTs, 390 SDValue N1, SDValue N2, SDValue N3, SDValue N4, 391 SDValue N5); 392 SDValue getNode(unsigned Opcode, SDVTList VTs, 393 const SDValue *Ops, unsigned NumOps); 394 395 SDValue getMemcpy(SDValue Chain, SDValue Dst, SDValue Src, 396 SDValue Size, unsigned Align, 397 bool AlwaysInline, 398 const Value *DstSV, uint64_t DstSVOff, 399 const Value *SrcSV, uint64_t SrcSVOff); 400 401 SDValue getMemmove(SDValue Chain, SDValue Dst, SDValue Src, 402 SDValue Size, unsigned Align, 403 const Value *DstSV, uint64_t DstOSVff, 404 const Value *SrcSV, uint64_t SrcSVOff); 405 406 SDValue getMemset(SDValue Chain, SDValue Dst, SDValue Src, 407 SDValue Size, unsigned Align, 408 const Value *DstSV, uint64_t DstSVOff); 409 410 /// getSetCC - Helper function to make it easier to build SetCC's if you just 411 /// have an ISD::CondCode instead of an SDValue. 412 /// 413 SDValue getSetCC(MVT VT, SDValue LHS, SDValue RHS, 414 ISD::CondCode Cond) { 415 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond)); 416 } 417 418 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes 419 /// if you just have an ISD::CondCode instead of an SDValue. 420 /// 421 SDValue getVSetCC(MVT VT, SDValue LHS, SDValue RHS, 422 ISD::CondCode Cond) { 423 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond)); 424 } 425 426 /// getSelectCC - Helper function to make it easier to build SelectCC's if you 427 /// just have an ISD::CondCode instead of an SDValue. 428 /// 429 SDValue getSelectCC(SDValue LHS, SDValue RHS, 430 SDValue True, SDValue False, ISD::CondCode Cond) { 431 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False, 432 getCondCode(Cond)); 433 } 434 435 /// getVAArg - VAArg produces a result and token chain, and takes a pointer 436 /// and a source value as input. 437 SDValue getVAArg(MVT VT, SDValue Chain, SDValue Ptr, 438 SDValue SV); 439 440 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes 441 /// 3 operands 442 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr, 443 SDValue Cmp, SDValue Swp, const Value* PtrVal, 444 unsigned Alignment=0); 445 446 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes 447 /// 2 operands 448 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr, 449 SDValue Val, const Value* PtrVal, 450 unsigned Alignment = 0); 451 452 /// getMergeValues - Create a MERGE_VALUES node from the given operands. 453 /// Allowed to return something different (and simpler) if Simplify is true. 454 SDValue getMergeValues(const SDValue *Ops, unsigned NumOps, 455 bool Simplify = true); 456 457 /// getMergeValues - Create a MERGE_VALUES node from the given types and ops. 458 /// Allowed to return something different (and simpler) if Simplify is true. 459 /// May be faster than the above version if VTs is known and NumOps is large. 460 SDValue getMergeValues(SDVTList VTs, const SDValue *Ops, unsigned NumOps, 461 bool Simplify = true) { 462 if (Simplify && NumOps == 1) 463 return Ops[0]; 464 return getNode(ISD::MERGE_VALUES, VTs, Ops, NumOps); 465 } 466 467 /// getCall - Create a CALL node from the given information. 468 /// 469 SDValue getCall(unsigned CallingConv, bool IsVarArgs, bool IsTailCall, 470 SDVTList VTs, const SDValue *Operands, unsigned NumOperands); 471 472 /// getLoad - Loads are not normal binary operators: their result type is not 473 /// determined by their operands, and they produce a value AND a token chain. 474 /// 475 SDValue getLoad(MVT VT, SDValue Chain, SDValue Ptr, 476 const Value *SV, int SVOffset, bool isVolatile=false, 477 unsigned Alignment=0); 478 SDValue getExtLoad(ISD::LoadExtType ExtType, MVT VT, 479 SDValue Chain, SDValue Ptr, const Value *SV, 480 int SVOffset, MVT EVT, bool isVolatile=false, 481 unsigned Alignment=0); 482 SDValue getIndexedLoad(SDValue OrigLoad, SDValue Base, 483 SDValue Offset, ISD::MemIndexedMode AM); 484 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType, 485 MVT VT, SDValue Chain, 486 SDValue Ptr, SDValue Offset, 487 const Value *SV, int SVOffset, MVT EVT, 488 bool isVolatile=false, unsigned Alignment=0); 489 490 /// getStore - Helper function to build ISD::STORE nodes. 491 /// 492 SDValue getStore(SDValue Chain, SDValue Val, SDValue Ptr, 493 const Value *SV, int SVOffset, bool isVolatile=false, 494 unsigned Alignment=0); 495 SDValue getTruncStore(SDValue Chain, SDValue Val, SDValue Ptr, 496 const Value *SV, int SVOffset, MVT TVT, 497 bool isVolatile=false, unsigned Alignment=0); 498 SDValue getIndexedStore(SDValue OrigStoe, SDValue Base, 499 SDValue Offset, ISD::MemIndexedMode AM); 500 501 // getSrcValue - Construct a node to track a Value* through the backend. 502 SDValue getSrcValue(const Value *v); 503 504 // getMemOperand - Construct a node to track a memory reference 505 // through the backend. 506 SDValue getMemOperand(const MachineMemOperand &MO); 507 508 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the 509 /// specified operands. If the resultant node already exists in the DAG, 510 /// this does not modify the specified node, instead it returns the node that 511 /// already exists. If the resultant node does not exist in the DAG, the 512 /// input node is returned. As a degenerate case, if you specify the same 513 /// input operands as the node already has, the input node is returned. 514 SDValue UpdateNodeOperands(SDValue N, SDValue Op); 515 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2); 516 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2, 517 SDValue Op3); 518 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2, 519 SDValue Op3, SDValue Op4); 520 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2, 521 SDValue Op3, SDValue Op4, SDValue Op5); 522 SDValue UpdateNodeOperands(SDValue N, 523 const SDValue *Ops, unsigned NumOps); 524 525 /// SelectNodeTo - These are used for target selectors to *mutate* the 526 /// specified node to have the specified return type, Target opcode, and 527 /// operands. Note that target opcodes are stored as 528 /// ~TargetOpcode in the node opcode field. The resultant node is returned. 529 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT); 530 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDValue Op1); 531 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, 532 SDValue Op1, SDValue Op2); 533 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, 534 SDValue Op1, SDValue Op2, SDValue Op3); 535 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, 536 const SDValue *Ops, unsigned NumOps); 537 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2); 538 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, 539 MVT VT2, const SDValue *Ops, unsigned NumOps); 540 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, 541 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps); 542 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, 543 MVT VT2, SDValue Op1); 544 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, 545 MVT VT2, SDValue Op1, SDValue Op2); 546 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, 547 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3); 548 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs, 549 const SDValue *Ops, unsigned NumOps); 550 551 /// MorphNodeTo - These *mutate* the specified node to have the specified 552 /// return type, opcode, and operands. 553 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT); 554 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, SDValue Op1); 555 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, 556 SDValue Op1, SDValue Op2); 557 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, 558 SDValue Op1, SDValue Op2, SDValue Op3); 559 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, 560 const SDValue *Ops, unsigned NumOps); 561 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, MVT VT2); 562 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, 563 MVT VT2, const SDValue *Ops, unsigned NumOps); 564 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, 565 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps); 566 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, 567 MVT VT2, SDValue Op1); 568 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, 569 MVT VT2, SDValue Op1, SDValue Op2); 570 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, 571 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3); 572 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs, 573 const SDValue *Ops, unsigned NumOps); 574 575 /// getTargetNode - These are used for target selectors to create a new node 576 /// with specified return type(s), target opcode, and operands. 577 /// 578 /// Note that getTargetNode returns the resultant node. If there is already a 579 /// node of the specified opcode and operands, it returns that node instead of 580 /// the current one. 581 SDNode *getTargetNode(unsigned Opcode, MVT VT); 582 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1); 583 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1, SDValue Op2); 584 SDNode *getTargetNode(unsigned Opcode, MVT VT, 585 SDValue Op1, SDValue Op2, SDValue Op3); 586 SDNode *getTargetNode(unsigned Opcode, MVT VT, 587 const SDValue *Ops, unsigned NumOps); 588 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2); 589 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDValue Op1); 590 SDNode *getTargetNode(unsigned Opcode, MVT VT1, 591 MVT VT2, SDValue Op1, SDValue Op2); 592 SDNode *getTargetNode(unsigned Opcode, MVT VT1, 593 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3); 594 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, 595 const SDValue *Ops, unsigned NumOps); 596 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, 597 SDValue Op1, SDValue Op2); 598 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, 599 SDValue Op1, SDValue Op2, SDValue Op3); 600 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, 601 const SDValue *Ops, unsigned NumOps); 602 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4, 603 const SDValue *Ops, unsigned NumOps); 604 SDNode *getTargetNode(unsigned Opcode, const std::vector<MVT> &ResultTys, 605 const SDValue *Ops, unsigned NumOps); 606 607 /// getNodeIfExists - Get the specified node if it's already available, or 608 /// else return NULL. 609 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs, 610 const SDValue *Ops, unsigned NumOps); 611 612 /// DAGUpdateListener - Clients of various APIs that cause global effects on 613 /// the DAG can optionally implement this interface. This allows the clients 614 /// to handle the various sorts of updates that happen. 615 class DAGUpdateListener { 616 public: 617 virtual ~DAGUpdateListener(); 618 619 /// NodeDeleted - The node N that was deleted and, if E is not null, an 620 /// equivalent node E that replaced it. 621 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0; 622 623 /// NodeUpdated - The node N that was updated. 624 virtual void NodeUpdated(SDNode *N) = 0; 625 }; 626 627 /// RemoveDeadNode - Remove the specified node from the system. If any of its 628 /// operands then becomes dead, remove them as well. Inform UpdateListener 629 /// for each node deleted. 630 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0); 631 632 /// RemoveDeadNodes - This method deletes the unreachable nodes in the 633 /// given list, and any nodes that become unreachable as a result. 634 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes, 635 DAGUpdateListener *UpdateListener = 0); 636 637 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead. 638 /// This can cause recursive merging of nodes in the DAG. Use the first 639 /// version if 'From' is known to have a single result, use the second 640 /// if you have two nodes with identical results, use the third otherwise. 641 /// 642 /// These methods all take an optional UpdateListener, which (if not null) is 643 /// informed about nodes that are deleted and modified due to recursive 644 /// changes in the dag. 645 /// 646 void ReplaceAllUsesWith(SDValue From, SDValue Op, 647 DAGUpdateListener *UpdateListener = 0); 648 void ReplaceAllUsesWith(SDNode *From, SDNode *To, 649 DAGUpdateListener *UpdateListener = 0); 650 void ReplaceAllUsesWith(SDNode *From, const SDValue *To, 651 DAGUpdateListener *UpdateListener = 0); 652 653 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving 654 /// uses of other values produced by From.Val alone. 655 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To, 656 DAGUpdateListener *UpdateListener = 0); 657 658 /// ReplaceAllUsesOfValuesWith - Like ReplaceAllUsesOfValueWith, but 659 /// for multiple values at once. This correctly handles the case where 660 /// there is an overlap between the From values and the To values. 661 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To, 662 unsigned Num, 663 DAGUpdateListener *UpdateListener = 0); 664 665 /// AssignTopologicalOrder - Assign a unique node id for each node in the DAG 666 /// based on their topological order. It returns the maximum id and a vector 667 /// of the SDNodes* in assigned order by reference. 668 unsigned AssignTopologicalOrder(std::vector<SDNode*> &TopOrder); 669 670 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary 671 /// operation. 672 static bool isCommutativeBinOp(unsigned Opcode) { 673 // FIXME: This should get its info from the td file, so that we can include 674 // target info. 675 switch (Opcode) { 676 case ISD::ADD: 677 case ISD::MUL: 678 case ISD::MULHU: 679 case ISD::MULHS: 680 case ISD::SMUL_LOHI: 681 case ISD::UMUL_LOHI: 682 case ISD::FADD: 683 case ISD::FMUL: 684 case ISD::AND: 685 case ISD::OR: 686 case ISD::XOR: 687 case ISD::ADDC: 688 case ISD::ADDE: return true; 689 default: return false; 690 } 691 } 692 693 void dump() const; 694 695 /// CreateStackTemporary - Create a stack temporary, suitable for holding the 696 /// specified value type. If minAlign is specified, the slot size will have 697 /// at least that alignment. 698 SDValue CreateStackTemporary(MVT VT, unsigned minAlign = 1); 699 700 /// FoldConstantArithmetic - 701 SDValue FoldConstantArithmetic(unsigned Opcode, 702 MVT VT, 703 ConstantSDNode *Cst1, 704 ConstantSDNode *Cst2); 705 706 /// FoldSetCC - Constant fold a setcc to true or false. 707 SDValue FoldSetCC(MVT VT, SDValue N1, 708 SDValue N2, ISD::CondCode Cond); 709 710 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We 711 /// use this predicate to simplify operations downstream. 712 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const; 713 714 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We 715 /// use this predicate to simplify operations downstream. Op and Mask are 716 /// known to be the same type. 717 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0) 718 const; 719 720 /// ComputeMaskedBits - Determine which of the bits specified in Mask are 721 /// known to be either zero or one and return them in the KnownZero/KnownOne 722 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit 723 /// processing. Targets can implement the computeMaskedBitsForTargetNode 724 /// method in the TargetLowering class to allow target nodes to be understood. 725 void ComputeMaskedBits(SDValue Op, const APInt &Mask, APInt &KnownZero, 726 APInt &KnownOne, unsigned Depth = 0) const; 727 728 /// ComputeNumSignBits - Return the number of times the sign bit of the 729 /// register is replicated into the other bits. We know that at least 1 bit 730 /// is always equal to the sign bit (itself), but other cases can give us 731 /// information. For example, immediately after an "SRA X, 2", we know that 732 /// the top 3 bits are all equal to each other, so we return 3. Targets can 733 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering 734 /// class to allow target nodes to be understood. 735 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const; 736 737 /// isVerifiedDebugInfoDesc - Returns true if the specified SDValue has 738 /// been verified as a debug information descriptor. 739 bool isVerifiedDebugInfoDesc(SDValue Op) const; 740 741 /// getShuffleScalarElt - Returns the scalar element that will make up the ith 742 /// element of the result of the vector shuffle. 743 SDValue getShuffleScalarElt(const SDNode *N, unsigned Idx); 744 745private: 746 bool RemoveNodeFromCSEMaps(SDNode *N); 747 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N); 748 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos); 749 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2, 750 void *&InsertPos); 751 SDNode *FindModifiedNodeSlot(SDNode *N, const SDValue *Ops, unsigned NumOps, 752 void *&InsertPos); 753 754 void DeleteNodeNotInCSEMaps(SDNode *N); 755 756 unsigned getMVTAlignment(MVT MemoryVT) const; 757 758 void allnodes_clear(); 759 760 // List of non-single value types. 761 std::vector<SDVTList> VTList; 762 763 // Maps to auto-CSE operations. 764 std::vector<CondCodeSDNode*> CondCodeNodes; 765 766 std::vector<SDNode*> ValueTypeNodes; 767 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes; 768 StringMap<SDNode*> ExternalSymbols; 769 StringMap<SDNode*> TargetExternalSymbols; 770}; 771 772template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> { 773 typedef SelectionDAG::allnodes_iterator nodes_iterator; 774 static nodes_iterator nodes_begin(SelectionDAG *G) { 775 return G->allnodes_begin(); 776 } 777 static nodes_iterator nodes_end(SelectionDAG *G) { 778 return G->allnodes_end(); 779 } 780}; 781 782} // end namespace llvm 783 784#endif 785