SelectionDAG.cpp revision 1e111c7bbb50eec1cb1ebc7d12fcfb22c36f8d87
1//===-- SelectionDAG.cpp - Implement the SelectionDAG data structures -----===// 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 implements the SelectionDAG class. 11// 12//===----------------------------------------------------------------------===// 13 14#include "llvm/CodeGen/SelectionDAG.h" 15#include "llvm/Constants.h" 16#include "llvm/GlobalValue.h" 17#include "llvm/Assembly/Writer.h" 18#include "llvm/CodeGen/MachineBasicBlock.h" 19#include "llvm/Support/MathExtras.h" 20#include "llvm/Target/MRegisterInfo.h" 21#include "llvm/Target/TargetLowering.h" 22#include "llvm/Target/TargetInstrInfo.h" 23#include "llvm/Target/TargetMachine.h" 24#include <iostream> 25#include <set> 26#include <cmath> 27#include <algorithm> 28using namespace llvm; 29 30// Temporary boolean for testing the dag combiner 31namespace llvm { 32 extern bool CombinerEnabled; 33} 34 35static bool isCommutativeBinOp(unsigned Opcode) { 36 switch (Opcode) { 37 case ISD::ADD: 38 case ISD::MUL: 39 case ISD::AND: 40 case ISD::OR: 41 case ISD::XOR: return true; 42 default: return false; // FIXME: Need commutative info for user ops! 43 } 44} 45 46static bool isAssociativeBinOp(unsigned Opcode) { 47 switch (Opcode) { 48 case ISD::ADD: 49 case ISD::MUL: 50 case ISD::AND: 51 case ISD::OR: 52 case ISD::XOR: return true; 53 default: return false; // FIXME: Need associative info for user ops! 54 } 55} 56 57// isInvertibleForFree - Return true if there is no cost to emitting the logical 58// inverse of this node. 59static bool isInvertibleForFree(SDOperand N) { 60 if (isa<ConstantSDNode>(N.Val)) return true; 61 if (N.Val->getOpcode() == ISD::SETCC && N.Val->hasOneUse()) 62 return true; 63 return false; 64} 65 66//===----------------------------------------------------------------------===// 67// ConstantFPSDNode Class 68//===----------------------------------------------------------------------===// 69 70/// isExactlyValue - We don't rely on operator== working on double values, as 71/// it returns true for things that are clearly not equal, like -0.0 and 0.0. 72/// As such, this method can be used to do an exact bit-for-bit comparison of 73/// two floating point values. 74bool ConstantFPSDNode::isExactlyValue(double V) const { 75 return DoubleToBits(V) == DoubleToBits(Value); 76} 77 78//===----------------------------------------------------------------------===// 79// ISD Class 80//===----------------------------------------------------------------------===// 81 82/// getSetCCSwappedOperands - Return the operation corresponding to (Y op X) 83/// when given the operation for (X op Y). 84ISD::CondCode ISD::getSetCCSwappedOperands(ISD::CondCode Operation) { 85 // To perform this operation, we just need to swap the L and G bits of the 86 // operation. 87 unsigned OldL = (Operation >> 2) & 1; 88 unsigned OldG = (Operation >> 1) & 1; 89 return ISD::CondCode((Operation & ~6) | // Keep the N, U, E bits 90 (OldL << 1) | // New G bit 91 (OldG << 2)); // New L bit. 92} 93 94/// getSetCCInverse - Return the operation corresponding to !(X op Y), where 95/// 'op' is a valid SetCC operation. 96ISD::CondCode ISD::getSetCCInverse(ISD::CondCode Op, bool isInteger) { 97 unsigned Operation = Op; 98 if (isInteger) 99 Operation ^= 7; // Flip L, G, E bits, but not U. 100 else 101 Operation ^= 15; // Flip all of the condition bits. 102 if (Operation > ISD::SETTRUE2) 103 Operation &= ~8; // Don't let N and U bits get set. 104 return ISD::CondCode(Operation); 105} 106 107 108/// isSignedOp - For an integer comparison, return 1 if the comparison is a 109/// signed operation and 2 if the result is an unsigned comparison. Return zero 110/// if the operation does not depend on the sign of the input (setne and seteq). 111static int isSignedOp(ISD::CondCode Opcode) { 112 switch (Opcode) { 113 default: assert(0 && "Illegal integer setcc operation!"); 114 case ISD::SETEQ: 115 case ISD::SETNE: return 0; 116 case ISD::SETLT: 117 case ISD::SETLE: 118 case ISD::SETGT: 119 case ISD::SETGE: return 1; 120 case ISD::SETULT: 121 case ISD::SETULE: 122 case ISD::SETUGT: 123 case ISD::SETUGE: return 2; 124 } 125} 126 127/// getSetCCOrOperation - Return the result of a logical OR between different 128/// comparisons of identical values: ((X op1 Y) | (X op2 Y)). This function 129/// returns SETCC_INVALID if it is not possible to represent the resultant 130/// comparison. 131ISD::CondCode ISD::getSetCCOrOperation(ISD::CondCode Op1, ISD::CondCode Op2, 132 bool isInteger) { 133 if (isInteger && (isSignedOp(Op1) | isSignedOp(Op2)) == 3) 134 // Cannot fold a signed integer setcc with an unsigned integer setcc. 135 return ISD::SETCC_INVALID; 136 137 unsigned Op = Op1 | Op2; // Combine all of the condition bits. 138 139 // If the N and U bits get set then the resultant comparison DOES suddenly 140 // care about orderedness, and is true when ordered. 141 if (Op > ISD::SETTRUE2) 142 Op &= ~16; // Clear the N bit. 143 return ISD::CondCode(Op); 144} 145 146/// getSetCCAndOperation - Return the result of a logical AND between different 147/// comparisons of identical values: ((X op1 Y) & (X op2 Y)). This 148/// function returns zero if it is not possible to represent the resultant 149/// comparison. 150ISD::CondCode ISD::getSetCCAndOperation(ISD::CondCode Op1, ISD::CondCode Op2, 151 bool isInteger) { 152 if (isInteger && (isSignedOp(Op1) | isSignedOp(Op2)) == 3) 153 // Cannot fold a signed setcc with an unsigned setcc. 154 return ISD::SETCC_INVALID; 155 156 // Combine all of the condition bits. 157 return ISD::CondCode(Op1 & Op2); 158} 159 160const TargetMachine &SelectionDAG::getTarget() const { 161 return TLI.getTargetMachine(); 162} 163 164//===----------------------------------------------------------------------===// 165// SelectionDAG Class 166//===----------------------------------------------------------------------===// 167 168/// RemoveDeadNodes - This method deletes all unreachable nodes in the 169/// SelectionDAG, including nodes (like loads) that have uses of their token 170/// chain but no other uses and no side effect. If a node is passed in as an 171/// argument, it is used as the seed for node deletion. 172void SelectionDAG::RemoveDeadNodes(SDNode *N) { 173 std::set<SDNode*> AllNodeSet(AllNodes.begin(), AllNodes.end()); 174 175 // Create a dummy node (which is not added to allnodes), that adds a reference 176 // to the root node, preventing it from being deleted. 177 SDNode *DummyNode = new SDNode(ISD::EntryToken, getRoot()); 178 179 // If we have a hint to start from, use it. 180 if (N) DeleteNodeIfDead(N, &AllNodeSet); 181 182 Restart: 183 unsigned NumNodes = AllNodeSet.size(); 184 for (std::set<SDNode*>::iterator I = AllNodeSet.begin(), E = AllNodeSet.end(); 185 I != E; ++I) { 186 // Try to delete this node. 187 DeleteNodeIfDead(*I, &AllNodeSet); 188 189 // If we actually deleted any nodes, do not use invalid iterators in 190 // AllNodeSet. 191 if (AllNodeSet.size() != NumNodes) 192 goto Restart; 193 } 194 195 // Restore AllNodes. 196 if (AllNodes.size() != NumNodes) 197 AllNodes.assign(AllNodeSet.begin(), AllNodeSet.end()); 198 199 // If the root changed (e.g. it was a dead load, update the root). 200 setRoot(DummyNode->getOperand(0)); 201 202 // Now that we are done with the dummy node, delete it. 203 DummyNode->getOperand(0).Val->removeUser(DummyNode); 204 delete DummyNode; 205} 206 207 208void SelectionDAG::DeleteNodeIfDead(SDNode *N, void *NodeSet) { 209 if (!N->use_empty()) 210 return; 211 212 // Okay, we really are going to delete this node. First take this out of the 213 // appropriate CSE map. 214 RemoveNodeFromCSEMaps(N); 215 216 // Next, brutally remove the operand list. This is safe to do, as there are 217 // no cycles in the graph. 218 while (!N->Operands.empty()) { 219 SDNode *O = N->Operands.back().Val; 220 N->Operands.pop_back(); 221 O->removeUser(N); 222 223 // Now that we removed this operand, see if there are no uses of it left. 224 DeleteNodeIfDead(O, NodeSet); 225 } 226 227 // Remove the node from the nodes set and delete it. 228 std::set<SDNode*> &AllNodeSet = *(std::set<SDNode*>*)NodeSet; 229 AllNodeSet.erase(N); 230 231 // Now that the node is gone, check to see if any of the operands of this node 232 // are dead now. 233 delete N; 234} 235 236void SelectionDAG::DeleteNode(SDNode *N) { 237 assert(N->use_empty() && "Cannot delete a node that is not dead!"); 238 239 // First take this out of the appropriate CSE map. 240 RemoveNodeFromCSEMaps(N); 241 242 // Finally, remove uses due to operands of this node, remove from the 243 // AllNodes list, and delete the node. 244 DeleteNodeNotInCSEMaps(N); 245} 246 247void SelectionDAG::DeleteNodeNotInCSEMaps(SDNode *N) { 248 249 // Remove it from the AllNodes list. 250 for (std::vector<SDNode*>::iterator I = AllNodes.begin(); ; ++I) { 251 assert(I != AllNodes.end() && "Node not in AllNodes list??"); 252 if (*I == N) { 253 // Erase from the vector, which is not ordered. 254 std::swap(*I, AllNodes.back()); 255 AllNodes.pop_back(); 256 break; 257 } 258 } 259 260 // Drop all of the operands and decrement used nodes use counts. 261 while (!N->Operands.empty()) { 262 SDNode *O = N->Operands.back().Val; 263 N->Operands.pop_back(); 264 O->removeUser(N); 265 } 266 267 delete N; 268} 269 270/// RemoveNodeFromCSEMaps - Take the specified node out of the CSE map that 271/// correspond to it. This is useful when we're about to delete or repurpose 272/// the node. We don't want future request for structurally identical nodes 273/// to return N anymore. 274void SelectionDAG::RemoveNodeFromCSEMaps(SDNode *N) { 275 bool Erased = false; 276 switch (N->getOpcode()) { 277 case ISD::Constant: 278 Erased = Constants.erase(std::make_pair(cast<ConstantSDNode>(N)->getValue(), 279 N->getValueType(0))); 280 break; 281 case ISD::TargetConstant: 282 Erased = TargetConstants.erase(std::make_pair( 283 cast<ConstantSDNode>(N)->getValue(), 284 N->getValueType(0))); 285 break; 286 case ISD::ConstantFP: { 287 uint64_t V = DoubleToBits(cast<ConstantFPSDNode>(N)->getValue()); 288 Erased = ConstantFPs.erase(std::make_pair(V, N->getValueType(0))); 289 break; 290 } 291 case ISD::CONDCODE: 292 assert(CondCodeNodes[cast<CondCodeSDNode>(N)->get()] && 293 "Cond code doesn't exist!"); 294 Erased = CondCodeNodes[cast<CondCodeSDNode>(N)->get()] != 0; 295 CondCodeNodes[cast<CondCodeSDNode>(N)->get()] = 0; 296 break; 297 case ISD::GlobalAddress: 298 Erased = GlobalValues.erase(cast<GlobalAddressSDNode>(N)->getGlobal()); 299 break; 300 case ISD::TargetGlobalAddress: 301 Erased =TargetGlobalValues.erase(cast<GlobalAddressSDNode>(N)->getGlobal()); 302 break; 303 case ISD::FrameIndex: 304 Erased = FrameIndices.erase(cast<FrameIndexSDNode>(N)->getIndex()); 305 break; 306 case ISD::TargetFrameIndex: 307 Erased = TargetFrameIndices.erase(cast<FrameIndexSDNode>(N)->getIndex()); 308 break; 309 case ISD::ConstantPool: 310 Erased = ConstantPoolIndices.erase(cast<ConstantPoolSDNode>(N)->get()); 311 break; 312 case ISD::TargetConstantPool: 313 Erased =TargetConstantPoolIndices.erase(cast<ConstantPoolSDNode>(N)->get()); 314 break; 315 case ISD::BasicBlock: 316 Erased = BBNodes.erase(cast<BasicBlockSDNode>(N)->getBasicBlock()); 317 break; 318 case ISD::ExternalSymbol: 319 Erased = ExternalSymbols.erase(cast<ExternalSymbolSDNode>(N)->getSymbol()); 320 break; 321 case ISD::VALUETYPE: 322 Erased = ValueTypeNodes[cast<VTSDNode>(N)->getVT()] != 0; 323 ValueTypeNodes[cast<VTSDNode>(N)->getVT()] = 0; 324 break; 325 case ISD::Register: 326 Erased = RegNodes.erase(std::make_pair(cast<RegisterSDNode>(N)->getReg(), 327 N->getValueType(0))); 328 break; 329 case ISD::SRCVALUE: { 330 SrcValueSDNode *SVN = cast<SrcValueSDNode>(N); 331 Erased =ValueNodes.erase(std::make_pair(SVN->getValue(), SVN->getOffset())); 332 break; 333 } 334 case ISD::LOAD: 335 Erased = Loads.erase(std::make_pair(N->getOperand(1), 336 std::make_pair(N->getOperand(0), 337 N->getValueType(0)))); 338 break; 339 default: 340 if (N->getNumValues() == 1) { 341 if (N->getNumOperands() == 0) { 342 Erased = NullaryOps.erase(std::make_pair(N->getOpcode(), 343 N->getValueType(0))); 344 } else if (N->getNumOperands() == 1) { 345 Erased = 346 UnaryOps.erase(std::make_pair(N->getOpcode(), 347 std::make_pair(N->getOperand(0), 348 N->getValueType(0)))); 349 } else if (N->getNumOperands() == 2) { 350 Erased = 351 BinaryOps.erase(std::make_pair(N->getOpcode(), 352 std::make_pair(N->getOperand(0), 353 N->getOperand(1)))); 354 } else { 355 std::vector<SDOperand> Ops(N->op_begin(), N->op_end()); 356 Erased = 357 OneResultNodes.erase(std::make_pair(N->getOpcode(), 358 std::make_pair(N->getValueType(0), 359 Ops))); 360 } 361 } else { 362 // Remove the node from the ArbitraryNodes map. 363 std::vector<MVT::ValueType> RV(N->value_begin(), N->value_end()); 364 std::vector<SDOperand> Ops(N->op_begin(), N->op_end()); 365 Erased = 366 ArbitraryNodes.erase(std::make_pair(N->getOpcode(), 367 std::make_pair(RV, Ops))); 368 } 369 break; 370 } 371#ifndef NDEBUG 372 // Verify that the node was actually in one of the CSE maps, unless it has a 373 // flag result (which cannot be CSE'd) or is one of the special cases that are 374 // not subject to CSE. 375 if (!Erased && N->getValueType(N->getNumValues()-1) != MVT::Flag && 376 N->getOpcode() != ISD::CALL && N->getOpcode() != ISD::CALLSEQ_START && 377 N->getOpcode() != ISD::CALLSEQ_END && !N->isTargetOpcode()) { 378 379 N->dump(); 380 assert(0 && "Node is not in map!"); 381 } 382#endif 383} 384 385/// AddNonLeafNodeToCSEMaps - Add the specified node back to the CSE maps. It 386/// has been taken out and modified in some way. If the specified node already 387/// exists in the CSE maps, do not modify the maps, but return the existing node 388/// instead. If it doesn't exist, add it and return null. 389/// 390SDNode *SelectionDAG::AddNonLeafNodeToCSEMaps(SDNode *N) { 391 assert(N->getNumOperands() && "This is a leaf node!"); 392 if (N->getOpcode() == ISD::LOAD) { 393 SDNode *&L = Loads[std::make_pair(N->getOperand(1), 394 std::make_pair(N->getOperand(0), 395 N->getValueType(0)))]; 396 if (L) return L; 397 L = N; 398 } else if (N->getNumOperands() == 1) { 399 SDNode *&U = UnaryOps[std::make_pair(N->getOpcode(), 400 std::make_pair(N->getOperand(0), 401 N->getValueType(0)))]; 402 if (U) return U; 403 U = N; 404 } else if (N->getNumOperands() == 2) { 405 SDNode *&B = BinaryOps[std::make_pair(N->getOpcode(), 406 std::make_pair(N->getOperand(0), 407 N->getOperand(1)))]; 408 if (B) return B; 409 B = N; 410 } else if (N->getNumValues() == 1) { 411 std::vector<SDOperand> Ops(N->op_begin(), N->op_end()); 412 SDNode *&ORN = OneResultNodes[std::make_pair(N->getOpcode(), 413 std::make_pair(N->getValueType(0), Ops))]; 414 if (ORN) return ORN; 415 ORN = N; 416 } else { 417 // Remove the node from the ArbitraryNodes map. 418 std::vector<MVT::ValueType> RV(N->value_begin(), N->value_end()); 419 std::vector<SDOperand> Ops(N->op_begin(), N->op_end()); 420 SDNode *&AN = ArbitraryNodes[std::make_pair(N->getOpcode(), 421 std::make_pair(RV, Ops))]; 422 if (AN) return AN; 423 AN = N; 424 } 425 return 0; 426 427} 428 429 430 431SelectionDAG::~SelectionDAG() { 432 for (unsigned i = 0, e = AllNodes.size(); i != e; ++i) 433 delete AllNodes[i]; 434} 435 436SDOperand SelectionDAG::getZeroExtendInReg(SDOperand Op, MVT::ValueType VT) { 437 if (Op.getValueType() == VT) return Op; 438 int64_t Imm = ~0ULL >> (64-MVT::getSizeInBits(VT)); 439 return getNode(ISD::AND, Op.getValueType(), Op, 440 getConstant(Imm, Op.getValueType())); 441} 442 443SDOperand SelectionDAG::getConstant(uint64_t Val, MVT::ValueType VT) { 444 assert(MVT::isInteger(VT) && "Cannot create FP integer constant!"); 445 // Mask out any bits that are not valid for this constant. 446 if (VT != MVT::i64) 447 Val &= ((uint64_t)1 << MVT::getSizeInBits(VT)) - 1; 448 449 SDNode *&N = Constants[std::make_pair(Val, VT)]; 450 if (N) return SDOperand(N, 0); 451 N = new ConstantSDNode(false, Val, VT); 452 AllNodes.push_back(N); 453 return SDOperand(N, 0); 454} 455 456SDOperand SelectionDAG::getTargetConstant(uint64_t Val, MVT::ValueType VT) { 457 assert(MVT::isInteger(VT) && "Cannot create FP integer constant!"); 458 // Mask out any bits that are not valid for this constant. 459 if (VT != MVT::i64) 460 Val &= ((uint64_t)1 << MVT::getSizeInBits(VT)) - 1; 461 462 SDNode *&N = TargetConstants[std::make_pair(Val, VT)]; 463 if (N) return SDOperand(N, 0); 464 N = new ConstantSDNode(true, Val, VT); 465 AllNodes.push_back(N); 466 return SDOperand(N, 0); 467} 468 469SDOperand SelectionDAG::getConstantFP(double Val, MVT::ValueType VT) { 470 assert(MVT::isFloatingPoint(VT) && "Cannot create integer FP constant!"); 471 if (VT == MVT::f32) 472 Val = (float)Val; // Mask out extra precision. 473 474 // Do the map lookup using the actual bit pattern for the floating point 475 // value, so that we don't have problems with 0.0 comparing equal to -0.0, and 476 // we don't have issues with SNANs. 477 SDNode *&N = ConstantFPs[std::make_pair(DoubleToBits(Val), VT)]; 478 if (N) return SDOperand(N, 0); 479 N = new ConstantFPSDNode(Val, VT); 480 AllNodes.push_back(N); 481 return SDOperand(N, 0); 482} 483 484 485 486SDOperand SelectionDAG::getGlobalAddress(const GlobalValue *GV, 487 MVT::ValueType VT) { 488 SDNode *&N = GlobalValues[GV]; 489 if (N) return SDOperand(N, 0); 490 N = new GlobalAddressSDNode(false, GV, VT); 491 AllNodes.push_back(N); 492 return SDOperand(N, 0); 493} 494 495SDOperand SelectionDAG::getTargetGlobalAddress(const GlobalValue *GV, 496 MVT::ValueType VT) { 497 SDNode *&N = TargetGlobalValues[GV]; 498 if (N) return SDOperand(N, 0); 499 N = new GlobalAddressSDNode(true, GV, VT); 500 AllNodes.push_back(N); 501 return SDOperand(N, 0); 502} 503 504SDOperand SelectionDAG::getFrameIndex(int FI, MVT::ValueType VT) { 505 SDNode *&N = FrameIndices[FI]; 506 if (N) return SDOperand(N, 0); 507 N = new FrameIndexSDNode(FI, VT, false); 508 AllNodes.push_back(N); 509 return SDOperand(N, 0); 510} 511 512SDOperand SelectionDAG::getTargetFrameIndex(int FI, MVT::ValueType VT) { 513 SDNode *&N = TargetFrameIndices[FI]; 514 if (N) return SDOperand(N, 0); 515 N = new FrameIndexSDNode(FI, VT, true); 516 AllNodes.push_back(N); 517 return SDOperand(N, 0); 518} 519 520SDOperand SelectionDAG::getConstantPool(Constant *C, MVT::ValueType VT) { 521 SDNode *&N = ConstantPoolIndices[C]; 522 if (N) return SDOperand(N, 0); 523 N = new ConstantPoolSDNode(C, VT, false); 524 AllNodes.push_back(N); 525 return SDOperand(N, 0); 526} 527 528SDOperand SelectionDAG::getTargetConstantPool(Constant *C, MVT::ValueType VT) { 529 SDNode *&N = TargetConstantPoolIndices[C]; 530 if (N) return SDOperand(N, 0); 531 N = new ConstantPoolSDNode(C, VT, true); 532 AllNodes.push_back(N); 533 return SDOperand(N, 0); 534} 535 536SDOperand SelectionDAG::getBasicBlock(MachineBasicBlock *MBB) { 537 SDNode *&N = BBNodes[MBB]; 538 if (N) return SDOperand(N, 0); 539 N = new BasicBlockSDNode(MBB); 540 AllNodes.push_back(N); 541 return SDOperand(N, 0); 542} 543 544SDOperand SelectionDAG::getValueType(MVT::ValueType VT) { 545 if ((unsigned)VT >= ValueTypeNodes.size()) 546 ValueTypeNodes.resize(VT+1); 547 if (ValueTypeNodes[VT] == 0) { 548 ValueTypeNodes[VT] = new VTSDNode(VT); 549 AllNodes.push_back(ValueTypeNodes[VT]); 550 } 551 552 return SDOperand(ValueTypeNodes[VT], 0); 553} 554 555SDOperand SelectionDAG::getExternalSymbol(const char *Sym, MVT::ValueType VT) { 556 SDNode *&N = ExternalSymbols[Sym]; 557 if (N) return SDOperand(N, 0); 558 N = new ExternalSymbolSDNode(Sym, VT); 559 AllNodes.push_back(N); 560 return SDOperand(N, 0); 561} 562 563SDOperand SelectionDAG::getCondCode(ISD::CondCode Cond) { 564 if ((unsigned)Cond >= CondCodeNodes.size()) 565 CondCodeNodes.resize(Cond+1); 566 567 if (CondCodeNodes[Cond] == 0) { 568 CondCodeNodes[Cond] = new CondCodeSDNode(Cond); 569 AllNodes.push_back(CondCodeNodes[Cond]); 570 } 571 return SDOperand(CondCodeNodes[Cond], 0); 572} 573 574SDOperand SelectionDAG::getRegister(unsigned RegNo, MVT::ValueType VT) { 575 RegisterSDNode *&Reg = RegNodes[std::make_pair(RegNo, VT)]; 576 if (!Reg) { 577 Reg = new RegisterSDNode(RegNo, VT); 578 AllNodes.push_back(Reg); 579 } 580 return SDOperand(Reg, 0); 581} 582 583SDOperand SelectionDAG::SimplifySetCC(MVT::ValueType VT, SDOperand N1, 584 SDOperand N2, ISD::CondCode Cond) { 585 // These setcc operations always fold. 586 switch (Cond) { 587 default: break; 588 case ISD::SETFALSE: 589 case ISD::SETFALSE2: return getConstant(0, VT); 590 case ISD::SETTRUE: 591 case ISD::SETTRUE2: return getConstant(1, VT); 592 } 593 594 if (ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2.Val)) { 595 uint64_t C2 = N2C->getValue(); 596 if (ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.Val)) { 597 uint64_t C1 = N1C->getValue(); 598 599 // Sign extend the operands if required 600 if (ISD::isSignedIntSetCC(Cond)) { 601 C1 = N1C->getSignExtended(); 602 C2 = N2C->getSignExtended(); 603 } 604 605 switch (Cond) { 606 default: assert(0 && "Unknown integer setcc!"); 607 case ISD::SETEQ: return getConstant(C1 == C2, VT); 608 case ISD::SETNE: return getConstant(C1 != C2, VT); 609 case ISD::SETULT: return getConstant(C1 < C2, VT); 610 case ISD::SETUGT: return getConstant(C1 > C2, VT); 611 case ISD::SETULE: return getConstant(C1 <= C2, VT); 612 case ISD::SETUGE: return getConstant(C1 >= C2, VT); 613 case ISD::SETLT: return getConstant((int64_t)C1 < (int64_t)C2, VT); 614 case ISD::SETGT: return getConstant((int64_t)C1 > (int64_t)C2, VT); 615 case ISD::SETLE: return getConstant((int64_t)C1 <= (int64_t)C2, VT); 616 case ISD::SETGE: return getConstant((int64_t)C1 >= (int64_t)C2, VT); 617 } 618 } else { 619 // If the LHS is a ZERO_EXTEND, perform the comparison on the input. 620 if (N1.getOpcode() == ISD::ZERO_EXTEND) { 621 unsigned InSize = MVT::getSizeInBits(N1.getOperand(0).getValueType()); 622 623 // If the comparison constant has bits in the upper part, the 624 // zero-extended value could never match. 625 if (C2 & (~0ULL << InSize)) { 626 unsigned VSize = MVT::getSizeInBits(N1.getValueType()); 627 switch (Cond) { 628 case ISD::SETUGT: 629 case ISD::SETUGE: 630 case ISD::SETEQ: return getConstant(0, VT); 631 case ISD::SETULT: 632 case ISD::SETULE: 633 case ISD::SETNE: return getConstant(1, VT); 634 case ISD::SETGT: 635 case ISD::SETGE: 636 // True if the sign bit of C2 is set. 637 return getConstant((C2 & (1ULL << VSize)) != 0, VT); 638 case ISD::SETLT: 639 case ISD::SETLE: 640 // True if the sign bit of C2 isn't set. 641 return getConstant((C2 & (1ULL << VSize)) == 0, VT); 642 default: 643 break; 644 } 645 } 646 647 // Otherwise, we can perform the comparison with the low bits. 648 switch (Cond) { 649 case ISD::SETEQ: 650 case ISD::SETNE: 651 case ISD::SETUGT: 652 case ISD::SETUGE: 653 case ISD::SETULT: 654 case ISD::SETULE: 655 return getSetCC(VT, N1.getOperand(0), 656 getConstant(C2, N1.getOperand(0).getValueType()), 657 Cond); 658 default: 659 break; // todo, be more careful with signed comparisons 660 } 661 } else if (N1.getOpcode() == ISD::SIGN_EXTEND_INREG && 662 (Cond == ISD::SETEQ || Cond == ISD::SETNE)) { 663 MVT::ValueType ExtSrcTy = cast<VTSDNode>(N1.getOperand(1))->getVT(); 664 unsigned ExtSrcTyBits = MVT::getSizeInBits(ExtSrcTy); 665 MVT::ValueType ExtDstTy = N1.getValueType(); 666 unsigned ExtDstTyBits = MVT::getSizeInBits(ExtDstTy); 667 668 // If the extended part has any inconsistent bits, it cannot ever 669 // compare equal. In other words, they have to be all ones or all 670 // zeros. 671 uint64_t ExtBits = 672 (~0ULL >> (64-ExtSrcTyBits)) & (~0ULL << (ExtDstTyBits-1)); 673 if ((C2 & ExtBits) != 0 && (C2 & ExtBits) != ExtBits) 674 return getConstant(Cond == ISD::SETNE, VT); 675 676 // Otherwise, make this a use of a zext. 677 return getSetCC(VT, getZeroExtendInReg(N1.getOperand(0), ExtSrcTy), 678 getConstant(C2 & (~0ULL>>(64-ExtSrcTyBits)), ExtDstTy), 679 Cond); 680 } 681 682 uint64_t MinVal, MaxVal; 683 unsigned OperandBitSize = MVT::getSizeInBits(N2C->getValueType(0)); 684 if (ISD::isSignedIntSetCC(Cond)) { 685 MinVal = 1ULL << (OperandBitSize-1); 686 if (OperandBitSize != 1) // Avoid X >> 64, which is undefined. 687 MaxVal = ~0ULL >> (65-OperandBitSize); 688 else 689 MaxVal = 0; 690 } else { 691 MinVal = 0; 692 MaxVal = ~0ULL >> (64-OperandBitSize); 693 } 694 695 // Canonicalize GE/LE comparisons to use GT/LT comparisons. 696 if (Cond == ISD::SETGE || Cond == ISD::SETUGE) { 697 if (C2 == MinVal) return getConstant(1, VT); // X >= MIN --> true 698 --C2; // X >= C1 --> X > (C1-1) 699 return getSetCC(VT, N1, getConstant(C2, N2.getValueType()), 700 (Cond == ISD::SETGE) ? ISD::SETGT : ISD::SETUGT); 701 } 702 703 if (Cond == ISD::SETLE || Cond == ISD::SETULE) { 704 if (C2 == MaxVal) return getConstant(1, VT); // X <= MAX --> true 705 ++C2; // X <= C1 --> X < (C1+1) 706 return getSetCC(VT, N1, getConstant(C2, N2.getValueType()), 707 (Cond == ISD::SETLE) ? ISD::SETLT : ISD::SETULT); 708 } 709 710 if ((Cond == ISD::SETLT || Cond == ISD::SETULT) && C2 == MinVal) 711 return getConstant(0, VT); // X < MIN --> false 712 713 // Canonicalize setgt X, Min --> setne X, Min 714 if ((Cond == ISD::SETGT || Cond == ISD::SETUGT) && C2 == MinVal) 715 return getSetCC(VT, N1, N2, ISD::SETNE); 716 717 // If we have setult X, 1, turn it into seteq X, 0 718 if ((Cond == ISD::SETLT || Cond == ISD::SETULT) && C2 == MinVal+1) 719 return getSetCC(VT, N1, getConstant(MinVal, N1.getValueType()), 720 ISD::SETEQ); 721 // If we have setugt X, Max-1, turn it into seteq X, Max 722 else if ((Cond == ISD::SETGT || Cond == ISD::SETUGT) && C2 == MaxVal-1) 723 return getSetCC(VT, N1, getConstant(MaxVal, N1.getValueType()), 724 ISD::SETEQ); 725 726 // If we have "setcc X, C1", check to see if we can shrink the immediate 727 // by changing cc. 728 729 // SETUGT X, SINTMAX -> SETLT X, 0 730 if (Cond == ISD::SETUGT && OperandBitSize != 1 && 731 C2 == (~0ULL >> (65-OperandBitSize))) 732 return getSetCC(VT, N1, getConstant(0, N2.getValueType()), ISD::SETLT); 733 734 // FIXME: Implement the rest of these. 735 736 737 // Fold bit comparisons when we can. 738 if ((Cond == ISD::SETEQ || Cond == ISD::SETNE) && 739 VT == N1.getValueType() && N1.getOpcode() == ISD::AND) 740 if (ConstantSDNode *AndRHS = 741 dyn_cast<ConstantSDNode>(N1.getOperand(1))) { 742 if (Cond == ISD::SETNE && C2 == 0) {// (X & 8) != 0 --> (X & 8) >> 3 743 // Perform the xform if the AND RHS is a single bit. 744 if ((AndRHS->getValue() & (AndRHS->getValue()-1)) == 0) { 745 return getNode(ISD::SRL, VT, N1, 746 getConstant(Log2_64(AndRHS->getValue()), 747 TLI.getShiftAmountTy())); 748 } 749 } else if (Cond == ISD::SETEQ && C2 == AndRHS->getValue()) { 750 // (X & 8) == 8 --> (X & 8) >> 3 751 // Perform the xform if C2 is a single bit. 752 if ((C2 & (C2-1)) == 0) { 753 return getNode(ISD::SRL, VT, N1, 754 getConstant(Log2_64(C2),TLI.getShiftAmountTy())); 755 } 756 } 757 } 758 } 759 } else if (isa<ConstantSDNode>(N1.Val)) { 760 // Ensure that the constant occurs on the RHS. 761 return getSetCC(VT, N2, N1, ISD::getSetCCSwappedOperands(Cond)); 762 } 763 764 if (ConstantFPSDNode *N1C = dyn_cast<ConstantFPSDNode>(N1.Val)) 765 if (ConstantFPSDNode *N2C = dyn_cast<ConstantFPSDNode>(N2.Val)) { 766 double C1 = N1C->getValue(), C2 = N2C->getValue(); 767 768 switch (Cond) { 769 default: break; // FIXME: Implement the rest of these! 770 case ISD::SETEQ: return getConstant(C1 == C2, VT); 771 case ISD::SETNE: return getConstant(C1 != C2, VT); 772 case ISD::SETLT: return getConstant(C1 < C2, VT); 773 case ISD::SETGT: return getConstant(C1 > C2, VT); 774 case ISD::SETLE: return getConstant(C1 <= C2, VT); 775 case ISD::SETGE: return getConstant(C1 >= C2, VT); 776 } 777 } else { 778 // Ensure that the constant occurs on the RHS. 779 return getSetCC(VT, N2, N1, ISD::getSetCCSwappedOperands(Cond)); 780 } 781 782 if (N1 == N2) { 783 // We can always fold X == Y for integer setcc's. 784 if (MVT::isInteger(N1.getValueType())) 785 return getConstant(ISD::isTrueWhenEqual(Cond), VT); 786 unsigned UOF = ISD::getUnorderedFlavor(Cond); 787 if (UOF == 2) // FP operators that are undefined on NaNs. 788 return getConstant(ISD::isTrueWhenEqual(Cond), VT); 789 if (UOF == unsigned(ISD::isTrueWhenEqual(Cond))) 790 return getConstant(UOF, VT); 791 // Otherwise, we can't fold it. However, we can simplify it to SETUO/SETO 792 // if it is not already. 793 ISD::CondCode NewCond = UOF == 0 ? ISD::SETUO : ISD::SETO; 794 if (NewCond != Cond) 795 return getSetCC(VT, N1, N2, NewCond); 796 } 797 798 if ((Cond == ISD::SETEQ || Cond == ISD::SETNE) && 799 MVT::isInteger(N1.getValueType())) { 800 if (N1.getOpcode() == ISD::ADD || N1.getOpcode() == ISD::SUB || 801 N1.getOpcode() == ISD::XOR) { 802 // Simplify (X+Y) == (X+Z) --> Y == Z 803 if (N1.getOpcode() == N2.getOpcode()) { 804 if (N1.getOperand(0) == N2.getOperand(0)) 805 return getSetCC(VT, N1.getOperand(1), N2.getOperand(1), Cond); 806 if (N1.getOperand(1) == N2.getOperand(1)) 807 return getSetCC(VT, N1.getOperand(0), N2.getOperand(0), Cond); 808 if (isCommutativeBinOp(N1.getOpcode())) { 809 // If X op Y == Y op X, try other combinations. 810 if (N1.getOperand(0) == N2.getOperand(1)) 811 return getSetCC(VT, N1.getOperand(1), N2.getOperand(0), Cond); 812 if (N1.getOperand(1) == N2.getOperand(0)) 813 return getSetCC(VT, N1.getOperand(1), N2.getOperand(1), Cond); 814 } 815 } 816 817 // FIXME: move this stuff to the DAG Combiner when it exists! 818 819 // Simplify (X+Z) == X --> Z == 0 820 if (N1.getOperand(0) == N2) 821 return getSetCC(VT, N1.getOperand(1), 822 getConstant(0, N1.getValueType()), Cond); 823 if (N1.getOperand(1) == N2) { 824 if (isCommutativeBinOp(N1.getOpcode())) 825 return getSetCC(VT, N1.getOperand(0), 826 getConstant(0, N1.getValueType()), Cond); 827 else { 828 assert(N1.getOpcode() == ISD::SUB && "Unexpected operation!"); 829 // (Z-X) == X --> Z == X<<1 830 return getSetCC(VT, N1.getOperand(0), 831 getNode(ISD::SHL, N2.getValueType(), 832 N2, getConstant(1, TLI.getShiftAmountTy())), 833 Cond); 834 } 835 } 836 } 837 838 if (N2.getOpcode() == ISD::ADD || N2.getOpcode() == ISD::SUB || 839 N2.getOpcode() == ISD::XOR) { 840 // Simplify X == (X+Z) --> Z == 0 841 if (N2.getOperand(0) == N1) { 842 return getSetCC(VT, N2.getOperand(1), 843 getConstant(0, N2.getValueType()), Cond); 844 } else if (N2.getOperand(1) == N1) { 845 if (isCommutativeBinOp(N2.getOpcode())) { 846 return getSetCC(VT, N2.getOperand(0), 847 getConstant(0, N2.getValueType()), Cond); 848 } else { 849 assert(N2.getOpcode() == ISD::SUB && "Unexpected operation!"); 850 // X == (Z-X) --> X<<1 == Z 851 return getSetCC(VT, getNode(ISD::SHL, N2.getValueType(), N1, 852 getConstant(1, TLI.getShiftAmountTy())), 853 N2.getOperand(0), Cond); 854 } 855 } 856 } 857 } 858 859 // Fold away ALL boolean setcc's. 860 if (N1.getValueType() == MVT::i1) { 861 switch (Cond) { 862 default: assert(0 && "Unknown integer setcc!"); 863 case ISD::SETEQ: // X == Y -> (X^Y)^1 864 N1 = getNode(ISD::XOR, MVT::i1, 865 getNode(ISD::XOR, MVT::i1, N1, N2), 866 getConstant(1, MVT::i1)); 867 break; 868 case ISD::SETNE: // X != Y --> (X^Y) 869 N1 = getNode(ISD::XOR, MVT::i1, N1, N2); 870 break; 871 case ISD::SETGT: // X >s Y --> X == 0 & Y == 1 --> X^1 & Y 872 case ISD::SETULT: // X <u Y --> X == 0 & Y == 1 --> X^1 & Y 873 N1 = getNode(ISD::AND, MVT::i1, N2, 874 getNode(ISD::XOR, MVT::i1, N1, getConstant(1, MVT::i1))); 875 break; 876 case ISD::SETLT: // X <s Y --> X == 1 & Y == 0 --> Y^1 & X 877 case ISD::SETUGT: // X >u Y --> X == 1 & Y == 0 --> Y^1 & X 878 N1 = getNode(ISD::AND, MVT::i1, N1, 879 getNode(ISD::XOR, MVT::i1, N2, getConstant(1, MVT::i1))); 880 break; 881 case ISD::SETULE: // X <=u Y --> X == 0 | Y == 1 --> X^1 | Y 882 case ISD::SETGE: // X >=s Y --> X == 0 | Y == 1 --> X^1 | Y 883 N1 = getNode(ISD::OR, MVT::i1, N2, 884 getNode(ISD::XOR, MVT::i1, N1, getConstant(1, MVT::i1))); 885 break; 886 case ISD::SETUGE: // X >=u Y --> X == 1 | Y == 0 --> Y^1 | X 887 case ISD::SETLE: // X <=s Y --> X == 1 | Y == 0 --> Y^1 | X 888 N1 = getNode(ISD::OR, MVT::i1, N1, 889 getNode(ISD::XOR, MVT::i1, N2, getConstant(1, MVT::i1))); 890 break; 891 } 892 if (VT != MVT::i1) 893 N1 = getNode(ISD::ZERO_EXTEND, VT, N1); 894 return N1; 895 } 896 897 // Could not fold it. 898 return SDOperand(); 899} 900 901SDOperand SelectionDAG::SimplifySelectCC(SDOperand N1, SDOperand N2, 902 SDOperand N3, SDOperand N4, 903 ISD::CondCode CC) { 904 MVT::ValueType VT = N3.getValueType(); 905 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.Val); 906 ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2.Val); 907 ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N3.Val); 908 ConstantSDNode *N4C = dyn_cast<ConstantSDNode>(N4.Val); 909 910 // Check to see if we can simplify the select into an fabs node 911 if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(N2)) { 912 // Allow either -0.0 or 0.0 913 if (CFP->getValue() == 0.0) { 914 // select (setg[te] X, +/-0.0), X, fneg(X) -> fabs 915 if ((CC == ISD::SETGE || CC == ISD::SETGT) && 916 N1 == N3 && N4.getOpcode() == ISD::FNEG && 917 N1 == N4.getOperand(0)) 918 return getNode(ISD::FABS, VT, N1); 919 920 // select (setl[te] X, +/-0.0), fneg(X), X -> fabs 921 if ((CC == ISD::SETLT || CC == ISD::SETLE) && 922 N1 == N4 && N3.getOpcode() == ISD::FNEG && 923 N3.getOperand(0) == N4) 924 return getNode(ISD::FABS, VT, N4); 925 } 926 } 927 928 // check to see if we're select_cc'ing a select_cc. 929 // this allows us to turn: 930 // select_cc set[eq,ne] (select_cc cc, lhs, rhs, 1, 0), 0, true, false -> 931 // select_cc cc, lhs, rhs, true, false 932 if ((N1C && N1C->isNullValue() && N2.getOpcode() == ISD::SELECT_CC) || 933 (N2C && N2C->isNullValue() && N1.getOpcode() == ISD::SELECT_CC) && 934 (CC == ISD::SETEQ || CC == ISD::SETNE)) { 935 SDOperand SCC = N1C ? N2 : N1; 936 ConstantSDNode *SCCT = dyn_cast<ConstantSDNode>(SCC.getOperand(2)); 937 ConstantSDNode *SCCF = dyn_cast<ConstantSDNode>(SCC.getOperand(3)); 938 if (SCCT && SCCF && SCCF->isNullValue() && SCCT->getValue() == 1ULL) { 939 if (CC == ISD::SETEQ) std::swap(N3, N4); 940 return getNode(ISD::SELECT_CC, N3.getValueType(), SCC.getOperand(0), 941 SCC.getOperand(1), N3, N4, SCC.getOperand(4)); 942 } 943 } 944 945 // Check to see if we can perform the "gzip trick", transforming 946 // select_cc setlt X, 0, A, 0 -> and (sra X, size(X)-1), A 947 if (N2C && N2C->isNullValue() && N4C && N4C->isNullValue() && 948 MVT::isInteger(N1.getValueType()) && 949 MVT::isInteger(N3.getValueType()) && CC == ISD::SETLT) { 950 MVT::ValueType XType = N1.getValueType(); 951 MVT::ValueType AType = N3.getValueType(); 952 if (XType >= AType) { 953 // and (sra X, size(X)-1, A) -> "and (srl X, C2), A" iff A is a 954 // single-bit constant. FIXME: remove once the dag combiner 955 // exists. 956 if (N3C && ((N3C->getValue() & (N3C->getValue()-1)) == 0)) { 957 unsigned ShCtV = Log2_64(N3C->getValue()); 958 ShCtV = MVT::getSizeInBits(XType)-ShCtV-1; 959 SDOperand ShCt = getConstant(ShCtV, TLI.getShiftAmountTy()); 960 SDOperand Shift = getNode(ISD::SRL, XType, N1, ShCt); 961 if (XType > AType) 962 Shift = getNode(ISD::TRUNCATE, AType, Shift); 963 return getNode(ISD::AND, AType, Shift, N3); 964 } 965 SDOperand Shift = getNode(ISD::SRA, XType, N1, 966 getConstant(MVT::getSizeInBits(XType)-1, 967 TLI.getShiftAmountTy())); 968 if (XType > AType) 969 Shift = getNode(ISD::TRUNCATE, AType, Shift); 970 return getNode(ISD::AND, AType, Shift, N3); 971 } 972 } 973 974 // Check to see if this is the equivalent of setcc 975 if (N4C && N4C->isNullValue() && N3C && (N3C->getValue() == 1ULL)) { 976 MVT::ValueType XType = N1.getValueType(); 977 if (TLI.isOperationLegal(ISD::SETCC, TLI.getSetCCResultTy())) 978 return getSetCC(TLI.getSetCCResultTy(), N1, N2, CC); 979 980 // seteq X, 0 -> srl (ctlz X, log2(size(X))) 981 if (N2C && N2C->isNullValue() && CC == ISD::SETEQ && 982 TLI.isOperationLegal(ISD::CTLZ, XType)) { 983 SDOperand Ctlz = getNode(ISD::CTLZ, XType, N1); 984 return getNode(ISD::SRL, XType, Ctlz, 985 getConstant(Log2_32(MVT::getSizeInBits(XType)), 986 TLI.getShiftAmountTy())); 987 } 988 // setgt X, 0 -> srl (and (-X, ~X), size(X)-1) 989 if (N2C && N2C->isNullValue() && CC == ISD::SETGT) { 990 SDOperand NegN1 = getNode(ISD::SUB, XType, getConstant(0, XType), N1); 991 SDOperand NotN1 = getNode(ISD::XOR, XType, N1, getConstant(~0ULL, XType)); 992 return getNode(ISD::SRL, XType, getNode(ISD::AND, XType, NegN1, NotN1), 993 getConstant(MVT::getSizeInBits(XType)-1, 994 TLI.getShiftAmountTy())); 995 } 996 // setgt X, -1 -> xor (srl (X, size(X)-1), 1) 997 if (N2C && N2C->isAllOnesValue() && CC == ISD::SETGT) { 998 SDOperand Sign = getNode(ISD::SRL, XType, N1, 999 getConstant(MVT::getSizeInBits(XType)-1, 1000 TLI.getShiftAmountTy())); 1001 return getNode(ISD::XOR, XType, Sign, getConstant(1, XType)); 1002 } 1003 } 1004 1005 // Check to see if this is an integer abs. select_cc setl[te] X, 0, -X, X -> 1006 // Y = sra (X, size(X)-1); xor (add (X, Y), Y) 1007 if (N2C && N2C->isNullValue() && (CC == ISD::SETLT || CC == ISD::SETLE) && 1008 N1 == N4 && N3.getOpcode() == ISD::SUB && N1 == N3.getOperand(1)) { 1009 if (ConstantSDNode *SubC = dyn_cast<ConstantSDNode>(N3.getOperand(0))) { 1010 MVT::ValueType XType = N1.getValueType(); 1011 if (SubC->isNullValue() && MVT::isInteger(XType)) { 1012 SDOperand Shift = getNode(ISD::SRA, XType, N1, 1013 getConstant(MVT::getSizeInBits(XType)-1, 1014 TLI.getShiftAmountTy())); 1015 return getNode(ISD::XOR, XType, getNode(ISD::ADD, XType, N1, Shift), 1016 Shift); 1017 } 1018 } 1019 } 1020 1021 // Could not fold it. 1022 return SDOperand(); 1023} 1024 1025/// getNode - Gets or creates the specified node. 1026/// 1027SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT) { 1028 SDNode *&N = NullaryOps[std::make_pair(Opcode, VT)]; 1029 if (!N) { 1030 N = new SDNode(Opcode, VT); 1031 AllNodes.push_back(N); 1032 } 1033 return SDOperand(N, 0); 1034} 1035 1036SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, 1037 SDOperand Operand) { 1038 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Operand.Val)) { 1039 uint64_t Val = C->getValue(); 1040 switch (Opcode) { 1041 default: break; 1042 case ISD::SIGN_EXTEND: return getConstant(C->getSignExtended(), VT); 1043 case ISD::ANY_EXTEND: 1044 case ISD::ZERO_EXTEND: return getConstant(Val, VT); 1045 case ISD::TRUNCATE: return getConstant(Val, VT); 1046 case ISD::SINT_TO_FP: return getConstantFP(C->getSignExtended(), VT); 1047 case ISD::UINT_TO_FP: return getConstantFP(C->getValue(), VT); 1048 } 1049 } 1050 1051 if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Operand.Val)) 1052 switch (Opcode) { 1053 case ISD::FNEG: 1054 return getConstantFP(-C->getValue(), VT); 1055 case ISD::FP_ROUND: 1056 case ISD::FP_EXTEND: 1057 return getConstantFP(C->getValue(), VT); 1058 case ISD::FP_TO_SINT: 1059 return getConstant((int64_t)C->getValue(), VT); 1060 case ISD::FP_TO_UINT: 1061 return getConstant((uint64_t)C->getValue(), VT); 1062 } 1063 1064 unsigned OpOpcode = Operand.Val->getOpcode(); 1065 switch (Opcode) { 1066 case ISD::TokenFactor: 1067 return Operand; // Factor of one node? No factor. 1068 case ISD::SIGN_EXTEND: 1069 if (Operand.getValueType() == VT) return Operand; // noop extension 1070 if (OpOpcode == ISD::SIGN_EXTEND || OpOpcode == ISD::ZERO_EXTEND) 1071 return getNode(OpOpcode, VT, Operand.Val->getOperand(0)); 1072 break; 1073 case ISD::ZERO_EXTEND: 1074 if (Operand.getValueType() == VT) return Operand; // noop extension 1075 if (OpOpcode == ISD::ZERO_EXTEND) // (zext (zext x)) -> (zext x) 1076 return getNode(ISD::ZERO_EXTEND, VT, Operand.Val->getOperand(0)); 1077 break; 1078 case ISD::ANY_EXTEND: 1079 if (Operand.getValueType() == VT) return Operand; // noop extension 1080 if (OpOpcode == ISD::ZERO_EXTEND || OpOpcode == ISD::SIGN_EXTEND) 1081 // (ext (zext x)) -> (zext x) and (ext (sext x)) -> (sext x) 1082 return getNode(OpOpcode, VT, Operand.Val->getOperand(0)); 1083 break; 1084 case ISD::TRUNCATE: 1085 if (Operand.getValueType() == VT) return Operand; // noop truncate 1086 if (OpOpcode == ISD::TRUNCATE) 1087 return getNode(ISD::TRUNCATE, VT, Operand.Val->getOperand(0)); 1088 else if (OpOpcode == ISD::ZERO_EXTEND || OpOpcode == ISD::SIGN_EXTEND || 1089 OpOpcode == ISD::ANY_EXTEND) { 1090 // If the source is smaller than the dest, we still need an extend. 1091 if (Operand.Val->getOperand(0).getValueType() < VT) 1092 return getNode(OpOpcode, VT, Operand.Val->getOperand(0)); 1093 else if (Operand.Val->getOperand(0).getValueType() > VT) 1094 return getNode(ISD::TRUNCATE, VT, Operand.Val->getOperand(0)); 1095 else 1096 return Operand.Val->getOperand(0); 1097 } 1098 break; 1099 case ISD::FNEG: 1100 if (OpOpcode == ISD::SUB) // -(X-Y) -> (Y-X) 1101 return getNode(ISD::SUB, VT, Operand.Val->getOperand(1), 1102 Operand.Val->getOperand(0)); 1103 if (OpOpcode == ISD::FNEG) // --X -> X 1104 return Operand.Val->getOperand(0); 1105 break; 1106 case ISD::FABS: 1107 if (OpOpcode == ISD::FNEG) // abs(-X) -> abs(X) 1108 return getNode(ISD::FABS, VT, Operand.Val->getOperand(0)); 1109 break; 1110 } 1111 1112 SDNode *N; 1113 if (VT != MVT::Flag) { // Don't CSE flag producing nodes 1114 SDNode *&E = UnaryOps[std::make_pair(Opcode, std::make_pair(Operand, VT))]; 1115 if (E) return SDOperand(E, 0); 1116 E = N = new SDNode(Opcode, Operand); 1117 } else { 1118 N = new SDNode(Opcode, Operand); 1119 } 1120 N->setValueTypes(VT); 1121 AllNodes.push_back(N); 1122 return SDOperand(N, 0); 1123} 1124 1125/// MaskedValueIsZero - Return true if 'V & Mask' is known to be zero. We use 1126/// this predicate to simplify operations downstream. V and Mask are known to 1127/// be the same type. 1128static bool MaskedValueIsZero(const SDOperand &Op, uint64_t Mask, 1129 const TargetLowering &TLI) { 1130 unsigned SrcBits; 1131 if (Mask == 0) return true; 1132 1133 // If we know the result of a setcc has the top bits zero, use this info. 1134 switch (Op.getOpcode()) { 1135 case ISD::Constant: 1136 return (cast<ConstantSDNode>(Op)->getValue() & Mask) == 0; 1137 1138 case ISD::SETCC: 1139 return ((Mask & 1) == 0) && 1140 TLI.getSetCCResultContents() == TargetLowering::ZeroOrOneSetCCResult; 1141 1142 case ISD::ZEXTLOAD: 1143 SrcBits = MVT::getSizeInBits(cast<VTSDNode>(Op.getOperand(3))->getVT()); 1144 return (Mask & ((1ULL << SrcBits)-1)) == 0; // Returning only the zext bits. 1145 case ISD::ZERO_EXTEND: 1146 SrcBits = MVT::getSizeInBits(Op.getOperand(0).getValueType()); 1147 return MaskedValueIsZero(Op.getOperand(0),Mask & ((1ULL << SrcBits)-1),TLI); 1148 case ISD::AssertZext: 1149 SrcBits = MVT::getSizeInBits(cast<VTSDNode>(Op.getOperand(1))->getVT()); 1150 return (Mask & ((1ULL << SrcBits)-1)) == 0; // Returning only the zext bits. 1151 case ISD::AND: 1152 // (X & C1) & C2 == 0 iff C1 & C2 == 0. 1153 if (ConstantSDNode *AndRHS = dyn_cast<ConstantSDNode>(Op.getOperand(1))) 1154 return MaskedValueIsZero(Op.getOperand(0),AndRHS->getValue() & Mask, TLI); 1155 1156 // FALL THROUGH 1157 case ISD::OR: 1158 case ISD::XOR: 1159 return MaskedValueIsZero(Op.getOperand(0), Mask, TLI) && 1160 MaskedValueIsZero(Op.getOperand(1), Mask, TLI); 1161 case ISD::SELECT: 1162 return MaskedValueIsZero(Op.getOperand(1), Mask, TLI) && 1163 MaskedValueIsZero(Op.getOperand(2), Mask, TLI); 1164 case ISD::SELECT_CC: 1165 return MaskedValueIsZero(Op.getOperand(2), Mask, TLI) && 1166 MaskedValueIsZero(Op.getOperand(3), Mask, TLI); 1167 case ISD::SRL: 1168 // (ushr X, C1) & C2 == 0 iff X & (C2 << C1) == 0 1169 if (ConstantSDNode *ShAmt = dyn_cast<ConstantSDNode>(Op.getOperand(1))) { 1170 uint64_t NewVal = Mask << ShAmt->getValue(); 1171 SrcBits = MVT::getSizeInBits(Op.getValueType()); 1172 if (SrcBits != 64) NewVal &= (1ULL << SrcBits)-1; 1173 return MaskedValueIsZero(Op.getOperand(0), NewVal, TLI); 1174 } 1175 return false; 1176 case ISD::SHL: 1177 // (ushl X, C1) & C2 == 0 iff X & (C2 >> C1) == 0 1178 if (ConstantSDNode *ShAmt = dyn_cast<ConstantSDNode>(Op.getOperand(1))) { 1179 uint64_t NewVal = Mask >> ShAmt->getValue(); 1180 return MaskedValueIsZero(Op.getOperand(0), NewVal, TLI); 1181 } 1182 return false; 1183 case ISD::CTTZ: 1184 case ISD::CTLZ: 1185 case ISD::CTPOP: 1186 // Bit counting instructions can not set the high bits of the result 1187 // register. The max number of bits sets depends on the input. 1188 return (Mask & (MVT::getSizeInBits(Op.getValueType())*2-1)) == 0; 1189 1190 // TODO we could handle some SRA cases here. 1191 default: break; 1192 } 1193 1194 return false; 1195} 1196 1197 1198 1199SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, 1200 SDOperand N1, SDOperand N2) { 1201#ifndef NDEBUG 1202 switch (Opcode) { 1203 case ISD::TokenFactor: 1204 assert(VT == MVT::Other && N1.getValueType() == MVT::Other && 1205 N2.getValueType() == MVT::Other && "Invalid token factor!"); 1206 break; 1207 case ISD::AND: 1208 case ISD::OR: 1209 case ISD::XOR: 1210 case ISD::UDIV: 1211 case ISD::UREM: 1212 case ISD::MULHU: 1213 case ISD::MULHS: 1214 assert(MVT::isInteger(VT) && "This operator does not apply to FP types!"); 1215 // fall through 1216 case ISD::ADD: 1217 case ISD::SUB: 1218 case ISD::MUL: 1219 case ISD::SDIV: 1220 case ISD::SREM: 1221 assert(N1.getValueType() == N2.getValueType() && 1222 N1.getValueType() == VT && "Binary operator types must match!"); 1223 break; 1224 1225 case ISD::SHL: 1226 case ISD::SRA: 1227 case ISD::SRL: 1228 assert(VT == N1.getValueType() && 1229 "Shift operators return type must be the same as their first arg"); 1230 assert(MVT::isInteger(VT) && MVT::isInteger(N2.getValueType()) && 1231 VT != MVT::i1 && "Shifts only work on integers"); 1232 break; 1233 case ISD::FP_ROUND_INREG: { 1234 MVT::ValueType EVT = cast<VTSDNode>(N2)->getVT(); 1235 assert(VT == N1.getValueType() && "Not an inreg round!"); 1236 assert(MVT::isFloatingPoint(VT) && MVT::isFloatingPoint(EVT) && 1237 "Cannot FP_ROUND_INREG integer types"); 1238 assert(EVT <= VT && "Not rounding down!"); 1239 break; 1240 } 1241 case ISD::AssertSext: 1242 case ISD::AssertZext: 1243 case ISD::SIGN_EXTEND_INREG: { 1244 MVT::ValueType EVT = cast<VTSDNode>(N2)->getVT(); 1245 assert(VT == N1.getValueType() && "Not an inreg extend!"); 1246 assert(MVT::isInteger(VT) && MVT::isInteger(EVT) && 1247 "Cannot *_EXTEND_INREG FP types"); 1248 assert(EVT <= VT && "Not extending!"); 1249 } 1250 1251 default: break; 1252 } 1253#endif 1254 1255 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.Val); 1256 ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2.Val); 1257 if (N1C) { 1258 if (N2C) { 1259 if (!CombinerEnabled) { 1260 uint64_t C1 = N1C->getValue(), C2 = N2C->getValue(); 1261 switch (Opcode) { 1262 case ISD::ADD: return getConstant(C1 + C2, VT); 1263 case ISD::SUB: return getConstant(C1 - C2, VT); 1264 case ISD::MUL: return getConstant(C1 * C2, VT); 1265 case ISD::UDIV: 1266 if (C2) return getConstant(C1 / C2, VT); 1267 break; 1268 case ISD::UREM : 1269 if (C2) return getConstant(C1 % C2, VT); 1270 break; 1271 case ISD::SDIV : 1272 if (C2) return getConstant(N1C->getSignExtended() / 1273 N2C->getSignExtended(), VT); 1274 break; 1275 case ISD::SREM : 1276 if (C2) return getConstant(N1C->getSignExtended() % 1277 N2C->getSignExtended(), VT); 1278 break; 1279 case ISD::AND : return getConstant(C1 & C2, VT); 1280 case ISD::OR : return getConstant(C1 | C2, VT); 1281 case ISD::XOR : return getConstant(C1 ^ C2, VT); 1282 case ISD::SHL : return getConstant(C1 << C2, VT); 1283 case ISD::SRL : return getConstant(C1 >> C2, VT); 1284 case ISD::SRA : return getConstant(N1C->getSignExtended() >>(int)C2, VT); 1285 default: break; 1286 } 1287 } 1288 } else { // Cannonicalize constant to RHS if commutative 1289 if (isCommutativeBinOp(Opcode)) { 1290 std::swap(N1C, N2C); 1291 std::swap(N1, N2); 1292 } 1293 } 1294 1295 if (!CombinerEnabled) { 1296 switch (Opcode) { 1297 default: break; 1298 case ISD::SHL: // shl 0, X -> 0 1299 if (N1C->isNullValue()) return N1; 1300 break; 1301 case ISD::SRL: // srl 0, X -> 0 1302 if (N1C->isNullValue()) return N1; 1303 break; 1304 case ISD::SRA: // sra -1, X -> -1 1305 if (N1C->isAllOnesValue()) return N1; 1306 break; 1307 case ISD::SIGN_EXTEND_INREG: // SIGN_EXTEND_INREG N1C, EVT 1308 // Extending a constant? Just return the extended constant. 1309 SDOperand Tmp = getNode(ISD::TRUNCATE, cast<VTSDNode>(N2)->getVT(), N1); 1310 return getNode(ISD::SIGN_EXTEND, VT, Tmp); 1311 } 1312 } 1313 } 1314 1315 if (N2C) { 1316 uint64_t C2 = N2C->getValue(); 1317 1318 switch (Opcode) { 1319 case ISD::ADD: 1320 if (!C2) return N1; // add X, 0 -> X 1321 break; 1322 case ISD::SUB: 1323 if (!C2) return N1; // sub X, 0 -> X 1324 return getNode(ISD::ADD, VT, N1, getConstant(-C2, VT)); 1325 case ISD::MUL: 1326 if (!C2) return N2; // mul X, 0 -> 0 1327 if (N2C->isAllOnesValue()) // mul X, -1 -> 0-X 1328 return getNode(ISD::SUB, VT, getConstant(0, VT), N1); 1329 1330 // FIXME: Move this to the DAG combiner when it exists. 1331 if ((C2 & C2-1) == 0) { 1332 SDOperand ShAmt = getConstant(Log2_64(C2), TLI.getShiftAmountTy()); 1333 return getNode(ISD::SHL, VT, N1, ShAmt); 1334 } 1335 break; 1336 1337 case ISD::MULHU: 1338 case ISD::MULHS: 1339 if (!C2) return N2; // mul X, 0 -> 0 1340 1341 if (C2 == 1) // 0X*01 -> 0X hi(0X) == 0 1342 return getConstant(0, VT); 1343 1344 // Many others could be handled here, including -1, powers of 2, etc. 1345 break; 1346 1347 case ISD::UDIV: 1348 // FIXME: Move this to the DAG combiner when it exists. 1349 if ((C2 & C2-1) == 0 && C2) { 1350 SDOperand ShAmt = getConstant(Log2_64(C2), TLI.getShiftAmountTy()); 1351 return getNode(ISD::SRL, VT, N1, ShAmt); 1352 } 1353 break; 1354 1355 case ISD::SHL: 1356 case ISD::SRL: 1357 case ISD::SRA: 1358 // If the shift amount is bigger than the size of the data, then all the 1359 // bits are shifted out. Simplify to undef. 1360 if (C2 >= MVT::getSizeInBits(N1.getValueType())) { 1361 return getNode(ISD::UNDEF, N1.getValueType()); 1362 } 1363 if (C2 == 0) return N1; 1364 1365 if (Opcode == ISD::SRA) { 1366 // If the sign bit is known to be zero, switch this to a SRL. 1367 if (MaskedValueIsZero(N1, 1368 1ULL << (MVT::getSizeInBits(N1.getValueType())-1), 1369 TLI)) 1370 return getNode(ISD::SRL, N1.getValueType(), N1, N2); 1371 } else { 1372 // If the part left over is known to be zero, the whole thing is zero. 1373 uint64_t TypeMask = ~0ULL >> (64-MVT::getSizeInBits(N1.getValueType())); 1374 if (Opcode == ISD::SRL) { 1375 if (MaskedValueIsZero(N1, TypeMask << C2, TLI)) 1376 return getConstant(0, N1.getValueType()); 1377 } else if (Opcode == ISD::SHL) { 1378 if (MaskedValueIsZero(N1, TypeMask >> C2, TLI)) 1379 return getConstant(0, N1.getValueType()); 1380 } 1381 } 1382 1383 if (Opcode == ISD::SHL && N1.getNumOperands() == 2) 1384 if (ConstantSDNode *OpSA = dyn_cast<ConstantSDNode>(N1.getOperand(1))) { 1385 unsigned OpSAC = OpSA->getValue(); 1386 if (N1.getOpcode() == ISD::SHL) { 1387 if (C2+OpSAC >= MVT::getSizeInBits(N1.getValueType())) 1388 return getConstant(0, N1.getValueType()); 1389 return getNode(ISD::SHL, N1.getValueType(), N1.getOperand(0), 1390 getConstant(C2+OpSAC, N2.getValueType())); 1391 } else if (N1.getOpcode() == ISD::SRL) { 1392 // (X >> C1) << C2: if C2 > C1, ((X & ~0<<C1) << C2-C1) 1393 SDOperand Mask = getNode(ISD::AND, VT, N1.getOperand(0), 1394 getConstant(~0ULL << OpSAC, VT)); 1395 if (C2 > OpSAC) { 1396 return getNode(ISD::SHL, VT, Mask, 1397 getConstant(C2-OpSAC, N2.getValueType())); 1398 } else { 1399 // (X >> C1) << C2: if C2 <= C1, ((X & ~0<<C1) >> C1-C2) 1400 return getNode(ISD::SRL, VT, Mask, 1401 getConstant(OpSAC-C2, N2.getValueType())); 1402 } 1403 } else if (N1.getOpcode() == ISD::SRA) { 1404 // if C1 == C2, just mask out low bits. 1405 if (C2 == OpSAC) 1406 return getNode(ISD::AND, VT, N1.getOperand(0), 1407 getConstant(~0ULL << C2, VT)); 1408 } 1409 } 1410 break; 1411 1412 case ISD::AND: 1413 if (!C2) return N2; // X and 0 -> 0 1414 if (N2C->isAllOnesValue()) 1415 return N1; // X and -1 -> X 1416 1417 if (MaskedValueIsZero(N1, C2, TLI)) // X and 0 -> 0 1418 return getConstant(0, VT); 1419 1420 { 1421 uint64_t NotC2 = ~C2; 1422 if (VT != MVT::i64) 1423 NotC2 &= (1ULL << MVT::getSizeInBits(VT))-1; 1424 1425 if (MaskedValueIsZero(N1, NotC2, TLI)) 1426 return N1; // if (X & ~C2) -> 0, the and is redundant 1427 } 1428 1429 // FIXME: Should add a corresponding version of this for 1430 // ZERO_EXTEND/SIGN_EXTEND by converting them to an ANY_EXTEND node which 1431 // we don't have yet. 1432 // FIXME: NOW WE DO, add this. 1433 1434 // and (sign_extend_inreg x:16:32), 1 -> and x, 1 1435 if (N1.getOpcode() == ISD::SIGN_EXTEND_INREG) { 1436 // If we are masking out the part of our input that was extended, just 1437 // mask the input to the extension directly. 1438 unsigned ExtendBits = 1439 MVT::getSizeInBits(cast<VTSDNode>(N1.getOperand(1))->getVT()); 1440 if ((C2 & (~0ULL << ExtendBits)) == 0) 1441 return getNode(ISD::AND, VT, N1.getOperand(0), N2); 1442 } else if (N1.getOpcode() == ISD::OR) { 1443 if (ConstantSDNode *ORI = dyn_cast<ConstantSDNode>(N1.getOperand(1))) 1444 if ((ORI->getValue() & C2) == C2) { 1445 // If the 'or' is setting all of the bits that we are masking for, 1446 // we know the result of the AND will be the AND mask itself. 1447 return N2; 1448 } 1449 } 1450 break; 1451 case ISD::OR: 1452 if (!C2)return N1; // X or 0 -> X 1453 if (N2C->isAllOnesValue()) 1454 return N2; // X or -1 -> -1 1455 break; 1456 case ISD::XOR: 1457 if (!C2) return N1; // X xor 0 -> X 1458 if (N2C->getValue() == 1 && N1.Val->getOpcode() == ISD::SETCC) { 1459 SDNode *SetCC = N1.Val; 1460 // !(X op Y) -> (X !op Y) 1461 bool isInteger = MVT::isInteger(SetCC->getOperand(0).getValueType()); 1462 ISD::CondCode CC = cast<CondCodeSDNode>(SetCC->getOperand(2))->get(); 1463 return getSetCC(SetCC->getValueType(0), 1464 SetCC->getOperand(0), SetCC->getOperand(1), 1465 ISD::getSetCCInverse(CC, isInteger)); 1466 } else if (N2C->isAllOnesValue()) { 1467 if (N1.getOpcode() == ISD::AND || N1.getOpcode() == ISD::OR) { 1468 SDNode *Op = N1.Val; 1469 // !(X or Y) -> (!X and !Y) iff X or Y are freely invertible 1470 // !(X and Y) -> (!X or !Y) iff X or Y are freely invertible 1471 SDOperand LHS = Op->getOperand(0), RHS = Op->getOperand(1); 1472 if (isInvertibleForFree(RHS) || isInvertibleForFree(LHS)) { 1473 LHS = getNode(ISD::XOR, VT, LHS, N2); // RHS = ~LHS 1474 RHS = getNode(ISD::XOR, VT, RHS, N2); // RHS = ~RHS 1475 if (Op->getOpcode() == ISD::AND) 1476 return getNode(ISD::OR, VT, LHS, RHS); 1477 return getNode(ISD::AND, VT, LHS, RHS); 1478 } 1479 } 1480 // X xor -1 -> not(x) ? 1481 } 1482 break; 1483 } 1484 1485 // Reassociate ((X op C1) op C2) if possible. 1486 if (N1.getOpcode() == Opcode && isAssociativeBinOp(Opcode)) 1487 if (ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N1.Val->getOperand(1))) 1488 return getNode(Opcode, VT, N1.Val->getOperand(0), 1489 getNode(Opcode, VT, N2, N1.Val->getOperand(1))); 1490 } 1491 1492 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1.Val); 1493 ConstantFPSDNode *N2CFP = dyn_cast<ConstantFPSDNode>(N2.Val); 1494 if (N1CFP) { 1495 if (N2CFP) { 1496 if (!CombinerEnabled) { 1497 double C1 = N1CFP->getValue(), C2 = N2CFP->getValue(); 1498 switch (Opcode) { 1499 case ISD::ADD: return getConstantFP(C1 + C2, VT); 1500 case ISD::SUB: return getConstantFP(C1 - C2, VT); 1501 case ISD::MUL: return getConstantFP(C1 * C2, VT); 1502 case ISD::SDIV: 1503 if (C2) return getConstantFP(C1 / C2, VT); 1504 break; 1505 case ISD::SREM : 1506 if (C2) return getConstantFP(fmod(C1, C2), VT); 1507 break; 1508 default: break; 1509 } 1510 } 1511 } else { // Cannonicalize constant to RHS if commutative 1512 if (isCommutativeBinOp(Opcode)) { 1513 std::swap(N1CFP, N2CFP); 1514 std::swap(N1, N2); 1515 } 1516 } 1517 1518 if (Opcode == ISD::FP_ROUND_INREG) 1519 return getNode(ISD::FP_EXTEND, VT, 1520 getNode(ISD::FP_ROUND, cast<VTSDNode>(N2)->getVT(), N1)); 1521 } 1522 1523 // Finally, fold operations that do not require constants. 1524 switch (Opcode) { 1525 case ISD::TokenFactor: 1526 if (!CombinerEnabled) { 1527 if (N1.getOpcode() == ISD::EntryToken) 1528 return N2; 1529 if (N2.getOpcode() == ISD::EntryToken) 1530 return N1; 1531 } 1532 break; 1533 1534 case ISD::AND: 1535 case ISD::OR: 1536 if (N1.Val->getOpcode() == ISD::SETCC && N2.Val->getOpcode() == ISD::SETCC){ 1537 SDNode *LHS = N1.Val, *RHS = N2.Val; 1538 SDOperand LL = LHS->getOperand(0), RL = RHS->getOperand(0); 1539 SDOperand LR = LHS->getOperand(1), RR = RHS->getOperand(1); 1540 ISD::CondCode Op1 = cast<CondCodeSDNode>(LHS->getOperand(2))->get(); 1541 ISD::CondCode Op2 = cast<CondCodeSDNode>(RHS->getOperand(2))->get(); 1542 1543 if (LR == RR && isa<ConstantSDNode>(LR) && 1544 Op2 == Op1 && MVT::isInteger(LL.getValueType())) { 1545 // (X != 0) | (Y != 0) -> (X|Y != 0) 1546 // (X == 0) & (Y == 0) -> (X|Y == 0) 1547 // (X < 0) | (Y < 0) -> (X|Y < 0) 1548 if (cast<ConstantSDNode>(LR)->getValue() == 0 && 1549 ((Op2 == ISD::SETEQ && Opcode == ISD::AND) || 1550 (Op2 == ISD::SETNE && Opcode == ISD::OR) || 1551 (Op2 == ISD::SETLT && Opcode == ISD::OR))) 1552 return getSetCC(VT, getNode(ISD::OR, LR.getValueType(), LL, RL), LR, 1553 Op2); 1554 1555 if (cast<ConstantSDNode>(LR)->isAllOnesValue()) { 1556 // (X == -1) & (Y == -1) -> (X&Y == -1) 1557 // (X != -1) | (Y != -1) -> (X&Y != -1) 1558 // (X > -1) | (Y > -1) -> (X&Y > -1) 1559 if ((Opcode == ISD::AND && Op2 == ISD::SETEQ) || 1560 (Opcode == ISD::OR && Op2 == ISD::SETNE) || 1561 (Opcode == ISD::OR && Op2 == ISD::SETGT)) 1562 return getSetCC(VT, getNode(ISD::AND, LR.getValueType(), LL, RL), 1563 LR, Op2); 1564 // (X > -1) & (Y > -1) -> (X|Y > -1) 1565 if (Opcode == ISD::AND && Op2 == ISD::SETGT) 1566 return getSetCC(VT, getNode(ISD::OR, LR.getValueType(), LL, RL), 1567 LR, Op2); 1568 } 1569 } 1570 1571 // (X op1 Y) | (Y op2 X) -> (X op1 Y) | (X swapop2 Y) 1572 if (LL == RR && LR == RL) { 1573 Op2 = ISD::getSetCCSwappedOperands(Op2); 1574 goto MatchedBackwards; 1575 } 1576 1577 if (LL == RL && LR == RR) { 1578 MatchedBackwards: 1579 ISD::CondCode Result; 1580 bool isInteger = MVT::isInteger(LL.getValueType()); 1581 if (Opcode == ISD::OR) 1582 Result = ISD::getSetCCOrOperation(Op1, Op2, isInteger); 1583 else 1584 Result = ISD::getSetCCAndOperation(Op1, Op2, isInteger); 1585 1586 if (Result != ISD::SETCC_INVALID) 1587 return getSetCC(LHS->getValueType(0), LL, LR, Result); 1588 } 1589 } 1590 1591 // and/or zext(a), zext(b) -> zext(and/or a, b) 1592 if (N1.getOpcode() == ISD::ZERO_EXTEND && 1593 N2.getOpcode() == ISD::ZERO_EXTEND && 1594 N1.getOperand(0).getValueType() == N2.getOperand(0).getValueType()) 1595 return getNode(ISD::ZERO_EXTEND, VT, 1596 getNode(Opcode, N1.getOperand(0).getValueType(), 1597 N1.getOperand(0), N2.getOperand(0))); 1598 break; 1599 case ISD::XOR: 1600 if (N1 == N2) return getConstant(0, VT); // xor X, Y -> 0 1601 break; 1602 case ISD::ADD: 1603 if (N2.getOpcode() == ISD::FNEG) // (A+ (-B) -> A-B 1604 return getNode(ISD::SUB, VT, N1, N2.getOperand(0)); 1605 if (N1.getOpcode() == ISD::FNEG) // ((-A)+B) -> B-A 1606 return getNode(ISD::SUB, VT, N2, N1.getOperand(0)); 1607 if (N1.getOpcode() == ISD::SUB && isa<ConstantSDNode>(N1.getOperand(0)) && 1608 cast<ConstantSDNode>(N1.getOperand(0))->getValue() == 0) 1609 return getNode(ISD::SUB, VT, N2, N1.getOperand(1)); // (0-A)+B -> B-A 1610 if (N2.getOpcode() == ISD::SUB && isa<ConstantSDNode>(N2.getOperand(0)) && 1611 cast<ConstantSDNode>(N2.getOperand(0))->getValue() == 0) 1612 return getNode(ISD::SUB, VT, N1, N2.getOperand(1)); // A+(0-B) -> A-B 1613 if (N2.getOpcode() == ISD::SUB && N1 == N2.Val->getOperand(1) && 1614 !MVT::isFloatingPoint(N2.getValueType())) 1615 return N2.Val->getOperand(0); // A+(B-A) -> B 1616 break; 1617 case ISD::SUB: 1618 if (N1.getOpcode() == ISD::ADD) { 1619 if (N1.Val->getOperand(0) == N2 && 1620 !MVT::isFloatingPoint(N2.getValueType())) 1621 return N1.Val->getOperand(1); // (A+B)-A == B 1622 if (N1.Val->getOperand(1) == N2 && 1623 !MVT::isFloatingPoint(N2.getValueType())) 1624 return N1.Val->getOperand(0); // (A+B)-B == A 1625 } 1626 if (N2.getOpcode() == ISD::FNEG) // (A- (-B) -> A+B 1627 return getNode(ISD::ADD, VT, N1, N2.getOperand(0)); 1628 break; 1629 case ISD::FP_ROUND_INREG: 1630 if (cast<VTSDNode>(N2)->getVT() == VT) return N1; // Not actually rounding. 1631 break; 1632 case ISD::SIGN_EXTEND_INREG: { 1633 MVT::ValueType EVT = cast<VTSDNode>(N2)->getVT(); 1634 if (EVT == VT) return N1; // Not actually extending 1635 1636 // If we are sign extending an extension, use the original source. 1637 if (N1.getOpcode() == ISD::SIGN_EXTEND_INREG || 1638 N1.getOpcode() == ISD::AssertSext) 1639 if (cast<VTSDNode>(N1.getOperand(1))->getVT() <= EVT) 1640 return N1; 1641 1642 // If we are sign extending a sextload, return just the load. 1643 if (N1.getOpcode() == ISD::SEXTLOAD) 1644 if (cast<VTSDNode>(N1.getOperand(3))->getVT() <= EVT) 1645 return N1; 1646 1647 // If we are extending the result of a setcc, and we already know the 1648 // contents of the top bits, eliminate the extension. 1649 if (N1.getOpcode() == ISD::SETCC && 1650 TLI.getSetCCResultContents() == 1651 TargetLowering::ZeroOrNegativeOneSetCCResult) 1652 return N1; 1653 1654 // If we are sign extending the result of an (and X, C) operation, and we 1655 // know the extended bits are zeros already, don't do the extend. 1656 if (N1.getOpcode() == ISD::AND) 1657 if (ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getOperand(1))) { 1658 uint64_t Mask = N1C->getValue(); 1659 unsigned NumBits = MVT::getSizeInBits(EVT); 1660 if ((Mask & (~0ULL << (NumBits-1))) == 0) 1661 return N1; 1662 } 1663 break; 1664 } 1665 1666 // FIXME: figure out how to safely handle things like 1667 // int foo(int x) { return 1 << (x & 255); } 1668 // int bar() { return foo(256); } 1669#if 0 1670 case ISD::SHL: 1671 case ISD::SRL: 1672 case ISD::SRA: 1673 if (N2.getOpcode() == ISD::SIGN_EXTEND_INREG && 1674 cast<VTSDNode>(N2.getOperand(1))->getVT() != MVT::i1) 1675 return getNode(Opcode, VT, N1, N2.getOperand(0)); 1676 else if (N2.getOpcode() == ISD::AND) 1677 if (ConstantSDNode *AndRHS = dyn_cast<ConstantSDNode>(N2.getOperand(1))) { 1678 // If the and is only masking out bits that cannot effect the shift, 1679 // eliminate the and. 1680 unsigned NumBits = MVT::getSizeInBits(VT); 1681 if ((AndRHS->getValue() & (NumBits-1)) == NumBits-1) 1682 return getNode(Opcode, VT, N1, N2.getOperand(0)); 1683 } 1684 break; 1685#endif 1686 } 1687 1688 // Memoize this node if possible. 1689 SDNode *N; 1690 if (Opcode != ISD::CALLSEQ_START && Opcode != ISD::CALLSEQ_END && 1691 VT != MVT::Flag) { 1692 SDNode *&BON = BinaryOps[std::make_pair(Opcode, std::make_pair(N1, N2))]; 1693 if (BON) return SDOperand(BON, 0); 1694 1695 BON = N = new SDNode(Opcode, N1, N2); 1696 } else { 1697 N = new SDNode(Opcode, N1, N2); 1698 } 1699 1700 N->setValueTypes(VT); 1701 AllNodes.push_back(N); 1702 return SDOperand(N, 0); 1703} 1704 1705// setAdjCallChain - This method changes the token chain of an 1706// CALLSEQ_START/END node to be the specified operand. 1707void SDNode::setAdjCallChain(SDOperand N) { 1708 assert(N.getValueType() == MVT::Other); 1709 assert((getOpcode() == ISD::CALLSEQ_START || 1710 getOpcode() == ISD::CALLSEQ_END) && "Cannot adjust this node!"); 1711 1712 Operands[0].Val->removeUser(this); 1713 Operands[0] = N; 1714 N.Val->Uses.push_back(this); 1715} 1716 1717 1718 1719SDOperand SelectionDAG::getLoad(MVT::ValueType VT, 1720 SDOperand Chain, SDOperand Ptr, 1721 SDOperand SV) { 1722 SDNode *&N = Loads[std::make_pair(Ptr, std::make_pair(Chain, VT))]; 1723 if (N) return SDOperand(N, 0); 1724 N = new SDNode(ISD::LOAD, Chain, Ptr, SV); 1725 1726 // Loads have a token chain. 1727 N->setValueTypes(VT, MVT::Other); 1728 AllNodes.push_back(N); 1729 return SDOperand(N, 0); 1730} 1731 1732 1733SDOperand SelectionDAG::getExtLoad(unsigned Opcode, MVT::ValueType VT, 1734 SDOperand Chain, SDOperand Ptr, SDOperand SV, 1735 MVT::ValueType EVT) { 1736 std::vector<SDOperand> Ops; 1737 Ops.reserve(4); 1738 Ops.push_back(Chain); 1739 Ops.push_back(Ptr); 1740 Ops.push_back(SV); 1741 Ops.push_back(getValueType(EVT)); 1742 std::vector<MVT::ValueType> VTs; 1743 VTs.reserve(2); 1744 VTs.push_back(VT); VTs.push_back(MVT::Other); // Add token chain. 1745 return getNode(Opcode, VTs, Ops); 1746} 1747 1748SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, 1749 SDOperand N1, SDOperand N2, SDOperand N3) { 1750 // Perform various simplifications. 1751 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.Val); 1752 ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2.Val); 1753 ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N3.Val); 1754 switch (Opcode) { 1755 case ISD::SETCC: { 1756 // Use SimplifySetCC to simplify SETCC's. 1757 SDOperand Simp = SimplifySetCC(VT, N1, N2, cast<CondCodeSDNode>(N3)->get()); 1758 if (Simp.Val) return Simp; 1759 break; 1760 } 1761 case ISD::SELECT: 1762 if (N1C) 1763 if (N1C->getValue()) 1764 return N2; // select true, X, Y -> X 1765 else 1766 return N3; // select false, X, Y -> Y 1767 1768 if (N2 == N3) return N2; // select C, X, X -> X 1769 1770 if (VT == MVT::i1) { // Boolean SELECT 1771 if (N2C) { 1772 if (N2C->getValue()) // select C, 1, X -> C | X 1773 return getNode(ISD::OR, VT, N1, N3); 1774 else // select C, 0, X -> ~C & X 1775 return getNode(ISD::AND, VT, 1776 getNode(ISD::XOR, N1.getValueType(), N1, 1777 getConstant(1, N1.getValueType())), N3); 1778 } else if (N3C) { 1779 if (N3C->getValue()) // select C, X, 1 -> ~C | X 1780 return getNode(ISD::OR, VT, 1781 getNode(ISD::XOR, N1.getValueType(), N1, 1782 getConstant(1, N1.getValueType())), N2); 1783 else // select C, X, 0 -> C & X 1784 return getNode(ISD::AND, VT, N1, N2); 1785 } 1786 1787 if (N1 == N2) // X ? X : Y --> X ? 1 : Y --> X | Y 1788 return getNode(ISD::OR, VT, N1, N3); 1789 if (N1 == N3) // X ? Y : X --> X ? Y : 0 --> X & Y 1790 return getNode(ISD::AND, VT, N1, N2); 1791 } 1792 if (N1.getOpcode() == ISD::SETCC) { 1793 SDOperand Simp = SimplifySelectCC(N1.getOperand(0), N1.getOperand(1), N2, 1794 N3, cast<CondCodeSDNode>(N1.getOperand(2))->get()); 1795 if (Simp.Val) return Simp; 1796 } 1797 break; 1798 case ISD::BRCOND: 1799 if (N2C) 1800 if (N2C->getValue()) // Unconditional branch 1801 return getNode(ISD::BR, MVT::Other, N1, N3); 1802 else 1803 return N1; // Never-taken branch 1804 break; 1805 } 1806 1807 std::vector<SDOperand> Ops; 1808 Ops.reserve(3); 1809 Ops.push_back(N1); 1810 Ops.push_back(N2); 1811 Ops.push_back(N3); 1812 1813 // Memoize node if it doesn't produce a flag. 1814 SDNode *N; 1815 if (VT != MVT::Flag) { 1816 SDNode *&E = OneResultNodes[std::make_pair(Opcode,std::make_pair(VT, Ops))]; 1817 if (E) return SDOperand(E, 0); 1818 E = N = new SDNode(Opcode, N1, N2, N3); 1819 } else { 1820 N = new SDNode(Opcode, N1, N2, N3); 1821 } 1822 N->setValueTypes(VT); 1823 AllNodes.push_back(N); 1824 return SDOperand(N, 0); 1825} 1826 1827SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, 1828 SDOperand N1, SDOperand N2, SDOperand N3, 1829 SDOperand N4) { 1830 std::vector<SDOperand> Ops; 1831 Ops.reserve(4); 1832 Ops.push_back(N1); 1833 Ops.push_back(N2); 1834 Ops.push_back(N3); 1835 Ops.push_back(N4); 1836 return getNode(Opcode, VT, Ops); 1837} 1838 1839SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, 1840 SDOperand N1, SDOperand N2, SDOperand N3, 1841 SDOperand N4, SDOperand N5) { 1842 std::vector<SDOperand> Ops; 1843 Ops.reserve(5); 1844 Ops.push_back(N1); 1845 Ops.push_back(N2); 1846 Ops.push_back(N3); 1847 Ops.push_back(N4); 1848 Ops.push_back(N5); 1849 return getNode(Opcode, VT, Ops); 1850} 1851 1852 1853SDOperand SelectionDAG::getSrcValue(const Value *V, int Offset) { 1854 assert((!V || isa<PointerType>(V->getType())) && 1855 "SrcValue is not a pointer?"); 1856 SDNode *&N = ValueNodes[std::make_pair(V, Offset)]; 1857 if (N) return SDOperand(N, 0); 1858 1859 N = new SrcValueSDNode(V, Offset); 1860 AllNodes.push_back(N); 1861 return SDOperand(N, 0); 1862} 1863 1864SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, 1865 std::vector<SDOperand> &Ops) { 1866 switch (Ops.size()) { 1867 case 0: return getNode(Opcode, VT); 1868 case 1: return getNode(Opcode, VT, Ops[0]); 1869 case 2: return getNode(Opcode, VT, Ops[0], Ops[1]); 1870 case 3: return getNode(Opcode, VT, Ops[0], Ops[1], Ops[2]); 1871 default: break; 1872 } 1873 1874 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(Ops[1].Val); 1875 switch (Opcode) { 1876 default: break; 1877 case ISD::BRCONDTWOWAY: 1878 if (N1C) 1879 if (N1C->getValue()) // Unconditional branch to true dest. 1880 return getNode(ISD::BR, MVT::Other, Ops[0], Ops[2]); 1881 else // Unconditional branch to false dest. 1882 return getNode(ISD::BR, MVT::Other, Ops[0], Ops[3]); 1883 break; 1884 case ISD::BRTWOWAY_CC: 1885 assert(Ops.size() == 6 && "BRTWOWAY_CC takes 6 operands!"); 1886 assert(Ops[2].getValueType() == Ops[3].getValueType() && 1887 "LHS and RHS of comparison must have same type!"); 1888 break; 1889 case ISD::TRUNCSTORE: { 1890 assert(Ops.size() == 5 && "TRUNCSTORE takes 5 operands!"); 1891 MVT::ValueType EVT = cast<VTSDNode>(Ops[4])->getVT(); 1892#if 0 // FIXME: If the target supports EVT natively, convert to a truncate/store 1893 // If this is a truncating store of a constant, convert to the desired type 1894 // and store it instead. 1895 if (isa<Constant>(Ops[0])) { 1896 SDOperand Op = getNode(ISD::TRUNCATE, EVT, N1); 1897 if (isa<Constant>(Op)) 1898 N1 = Op; 1899 } 1900 // Also for ConstantFP? 1901#endif 1902 if (Ops[0].getValueType() == EVT) // Normal store? 1903 return getNode(ISD::STORE, VT, Ops[0], Ops[1], Ops[2], Ops[3]); 1904 assert(Ops[1].getValueType() > EVT && "Not a truncation?"); 1905 assert(MVT::isInteger(Ops[1].getValueType()) == MVT::isInteger(EVT) && 1906 "Can't do FP-INT conversion!"); 1907 break; 1908 } 1909 case ISD::SELECT_CC: { 1910 assert(Ops.size() == 5 && "TRUNCSTORE takes 5 operands!"); 1911 assert(Ops[0].getValueType() == Ops[1].getValueType() && 1912 "LHS and RHS of condition must have same type!"); 1913 assert(Ops[2].getValueType() == Ops[3].getValueType() && 1914 "True and False arms of SelectCC must have same type!"); 1915 assert(Ops[2].getValueType() == VT && 1916 "select_cc node must be of same type as true and false value!"); 1917 SDOperand Simp = SimplifySelectCC(Ops[0], Ops[1], Ops[2], Ops[3], 1918 cast<CondCodeSDNode>(Ops[4])->get()); 1919 if (Simp.Val) return Simp; 1920 break; 1921 } 1922 case ISD::BR_CC: { 1923 assert(Ops.size() == 5 && "TRUNCSTORE takes 5 operands!"); 1924 assert(Ops[2].getValueType() == Ops[3].getValueType() && 1925 "LHS/RHS of comparison should match types!"); 1926 // Use SimplifySetCC to simplify SETCC's. 1927 SDOperand Simp = SimplifySetCC(MVT::i1, Ops[2], Ops[3], 1928 cast<CondCodeSDNode>(Ops[1])->get()); 1929 if (Simp.Val) { 1930 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Simp)) { 1931 if (C->getValue() & 1) // Unconditional branch 1932 return getNode(ISD::BR, MVT::Other, Ops[0], Ops[4]); 1933 else 1934 return Ops[0]; // Unconditional Fall through 1935 } else if (Simp.Val->getOpcode() == ISD::SETCC) { 1936 Ops[2] = Simp.getOperand(0); 1937 Ops[3] = Simp.getOperand(1); 1938 Ops[1] = Simp.getOperand(2); 1939 } 1940 } 1941 break; 1942 } 1943 } 1944 1945 // Memoize nodes. 1946 SDNode *N; 1947 if (VT != MVT::Flag) { 1948 SDNode *&E = 1949 OneResultNodes[std::make_pair(Opcode, std::make_pair(VT, Ops))]; 1950 if (E) return SDOperand(E, 0); 1951 E = N = new SDNode(Opcode, Ops); 1952 } else { 1953 N = new SDNode(Opcode, Ops); 1954 } 1955 N->setValueTypes(VT); 1956 AllNodes.push_back(N); 1957 return SDOperand(N, 0); 1958} 1959 1960SDOperand SelectionDAG::getNode(unsigned Opcode, 1961 std::vector<MVT::ValueType> &ResultTys, 1962 std::vector<SDOperand> &Ops) { 1963 if (ResultTys.size() == 1) 1964 return getNode(Opcode, ResultTys[0], Ops); 1965 1966 switch (Opcode) { 1967 case ISD::EXTLOAD: 1968 case ISD::SEXTLOAD: 1969 case ISD::ZEXTLOAD: { 1970 MVT::ValueType EVT = cast<VTSDNode>(Ops[3])->getVT(); 1971 assert(Ops.size() == 4 && ResultTys.size() == 2 && "Bad *EXTLOAD!"); 1972 // If they are asking for an extending load from/to the same thing, return a 1973 // normal load. 1974 if (ResultTys[0] == EVT) 1975 return getLoad(ResultTys[0], Ops[0], Ops[1], Ops[2]); 1976 assert(EVT < ResultTys[0] && 1977 "Should only be an extending load, not truncating!"); 1978 assert((Opcode == ISD::EXTLOAD || MVT::isInteger(ResultTys[0])) && 1979 "Cannot sign/zero extend a FP load!"); 1980 assert(MVT::isInteger(ResultTys[0]) == MVT::isInteger(EVT) && 1981 "Cannot convert from FP to Int or Int -> FP!"); 1982 break; 1983 } 1984 1985 // FIXME: figure out how to safely handle things like 1986 // int foo(int x) { return 1 << (x & 255); } 1987 // int bar() { return foo(256); } 1988#if 0 1989 case ISD::SRA_PARTS: 1990 case ISD::SRL_PARTS: 1991 case ISD::SHL_PARTS: 1992 if (N3.getOpcode() == ISD::SIGN_EXTEND_INREG && 1993 cast<VTSDNode>(N3.getOperand(1))->getVT() != MVT::i1) 1994 return getNode(Opcode, VT, N1, N2, N3.getOperand(0)); 1995 else if (N3.getOpcode() == ISD::AND) 1996 if (ConstantSDNode *AndRHS = dyn_cast<ConstantSDNode>(N3.getOperand(1))) { 1997 // If the and is only masking out bits that cannot effect the shift, 1998 // eliminate the and. 1999 unsigned NumBits = MVT::getSizeInBits(VT)*2; 2000 if ((AndRHS->getValue() & (NumBits-1)) == NumBits-1) 2001 return getNode(Opcode, VT, N1, N2, N3.getOperand(0)); 2002 } 2003 break; 2004#endif 2005 } 2006 2007 // Memoize the node unless it returns a flag. 2008 SDNode *N; 2009 if (ResultTys.back() != MVT::Flag) { 2010 SDNode *&E = 2011 ArbitraryNodes[std::make_pair(Opcode, std::make_pair(ResultTys, Ops))]; 2012 if (E) return SDOperand(E, 0); 2013 E = N = new SDNode(Opcode, Ops); 2014 } else { 2015 N = new SDNode(Opcode, Ops); 2016 } 2017 N->setValueTypes(ResultTys); 2018 AllNodes.push_back(N); 2019 return SDOperand(N, 0); 2020} 2021 2022 2023/// SelectNodeTo - These are used for target selectors to *mutate* the 2024/// specified node to have the specified return type, Target opcode, and 2025/// operands. Note that target opcodes are stored as 2026/// ISD::BUILTIN_OP_END+TargetOpcode in the node opcode field. 2027void SelectionDAG::SelectNodeTo(SDNode *N, unsigned TargetOpc, 2028 MVT::ValueType VT) { 2029 RemoveNodeFromCSEMaps(N); 2030 N->MorphNodeTo(ISD::BUILTIN_OP_END+TargetOpc); 2031 N->setValueTypes(VT); 2032} 2033void SelectionDAG::SelectNodeTo(SDNode *N, unsigned TargetOpc, 2034 MVT::ValueType VT, SDOperand Op1) { 2035 RemoveNodeFromCSEMaps(N); 2036 N->MorphNodeTo(ISD::BUILTIN_OP_END+TargetOpc); 2037 N->setValueTypes(VT); 2038 N->setOperands(Op1); 2039} 2040void SelectionDAG::SelectNodeTo(SDNode *N, unsigned TargetOpc, 2041 MVT::ValueType VT, SDOperand Op1, 2042 SDOperand Op2) { 2043 RemoveNodeFromCSEMaps(N); 2044 N->MorphNodeTo(ISD::BUILTIN_OP_END+TargetOpc); 2045 N->setValueTypes(VT); 2046 N->setOperands(Op1, Op2); 2047} 2048void SelectionDAG::SelectNodeTo(SDNode *N, unsigned TargetOpc, 2049 MVT::ValueType VT1, MVT::ValueType VT2, 2050 SDOperand Op1, SDOperand Op2) { 2051 RemoveNodeFromCSEMaps(N); 2052 N->MorphNodeTo(ISD::BUILTIN_OP_END+TargetOpc); 2053 N->setValueTypes(VT1, VT2); 2054 N->setOperands(Op1, Op2); 2055} 2056void SelectionDAG::SelectNodeTo(SDNode *N, unsigned TargetOpc, 2057 MVT::ValueType VT, SDOperand Op1, 2058 SDOperand Op2, SDOperand Op3) { 2059 RemoveNodeFromCSEMaps(N); 2060 N->MorphNodeTo(ISD::BUILTIN_OP_END+TargetOpc); 2061 N->setValueTypes(VT); 2062 N->setOperands(Op1, Op2, Op3); 2063} 2064void SelectionDAG::SelectNodeTo(SDNode *N, unsigned TargetOpc, 2065 MVT::ValueType VT1, MVT::ValueType VT2, 2066 SDOperand Op1, SDOperand Op2, SDOperand Op3) { 2067 RemoveNodeFromCSEMaps(N); 2068 N->MorphNodeTo(ISD::BUILTIN_OP_END+TargetOpc); 2069 N->setValueTypes(VT1, VT2); 2070 N->setOperands(Op1, Op2, Op3); 2071} 2072 2073void SelectionDAG::SelectNodeTo(SDNode *N, unsigned TargetOpc, 2074 MVT::ValueType VT, SDOperand Op1, 2075 SDOperand Op2, SDOperand Op3, SDOperand Op4) { 2076 RemoveNodeFromCSEMaps(N); 2077 N->MorphNodeTo(ISD::BUILTIN_OP_END+TargetOpc); 2078 N->setValueTypes(VT); 2079 N->setOperands(Op1, Op2, Op3, Op4); 2080} 2081void SelectionDAG::SelectNodeTo(SDNode *N, unsigned TargetOpc, 2082 MVT::ValueType VT, SDOperand Op1, 2083 SDOperand Op2, SDOperand Op3, SDOperand Op4, 2084 SDOperand Op5) { 2085 RemoveNodeFromCSEMaps(N); 2086 N->MorphNodeTo(ISD::BUILTIN_OP_END+TargetOpc); 2087 N->setValueTypes(VT); 2088 N->setOperands(Op1, Op2, Op3, Op4, Op5); 2089} 2090 2091/// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead. 2092/// This can cause recursive merging of nodes in the DAG. 2093/// 2094/// This version assumes From/To have a single result value. 2095/// 2096void SelectionDAG::ReplaceAllUsesWith(SDOperand FromN, SDOperand ToN, 2097 std::vector<SDNode*> *Deleted) { 2098 SDNode *From = FromN.Val, *To = ToN.Val; 2099 assert(From->getNumValues() == 1 && To->getNumValues() == 1 && 2100 "Cannot replace with this method!"); 2101 assert(From != To && "Cannot replace uses of with self"); 2102 2103 while (!From->use_empty()) { 2104 // Process users until they are all gone. 2105 SDNode *U = *From->use_begin(); 2106 2107 // This node is about to morph, remove its old self from the CSE maps. 2108 RemoveNodeFromCSEMaps(U); 2109 2110 for (unsigned i = 0, e = U->getNumOperands(); i != e; ++i) 2111 if (U->getOperand(i).Val == From) { 2112 From->removeUser(U); 2113 U->Operands[i].Val = To; 2114 To->addUser(U); 2115 } 2116 2117 // Now that we have modified U, add it back to the CSE maps. If it already 2118 // exists there, recursively merge the results together. 2119 if (SDNode *Existing = AddNonLeafNodeToCSEMaps(U)) { 2120 ReplaceAllUsesWith(U, Existing, Deleted); 2121 // U is now dead. 2122 if (Deleted) Deleted->push_back(U); 2123 DeleteNodeNotInCSEMaps(U); 2124 } 2125 } 2126} 2127 2128/// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead. 2129/// This can cause recursive merging of nodes in the DAG. 2130/// 2131/// This version assumes From/To have matching types and numbers of result 2132/// values. 2133/// 2134void SelectionDAG::ReplaceAllUsesWith(SDNode *From, SDNode *To, 2135 std::vector<SDNode*> *Deleted) { 2136 assert(From != To && "Cannot replace uses of with self"); 2137 assert(From->getNumValues() == To->getNumValues() && 2138 "Cannot use this version of ReplaceAllUsesWith!"); 2139 if (From->getNumValues() == 1) { // If possible, use the faster version. 2140 ReplaceAllUsesWith(SDOperand(From, 0), SDOperand(To, 0), Deleted); 2141 return; 2142 } 2143 2144 while (!From->use_empty()) { 2145 // Process users until they are all gone. 2146 SDNode *U = *From->use_begin(); 2147 2148 // This node is about to morph, remove its old self from the CSE maps. 2149 RemoveNodeFromCSEMaps(U); 2150 2151 for (unsigned i = 0, e = U->getNumOperands(); i != e; ++i) 2152 if (U->getOperand(i).Val == From) { 2153 From->removeUser(U); 2154 U->Operands[i].Val = To; 2155 To->addUser(U); 2156 } 2157 2158 // Now that we have modified U, add it back to the CSE maps. If it already 2159 // exists there, recursively merge the results together. 2160 if (SDNode *Existing = AddNonLeafNodeToCSEMaps(U)) { 2161 ReplaceAllUsesWith(U, Existing, Deleted); 2162 // U is now dead. 2163 if (Deleted) Deleted->push_back(U); 2164 DeleteNodeNotInCSEMaps(U); 2165 } 2166 } 2167} 2168 2169/// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead. 2170/// This can cause recursive merging of nodes in the DAG. 2171/// 2172/// This version can replace From with any result values. To must match the 2173/// number and types of values returned by From. 2174void SelectionDAG::ReplaceAllUsesWith(SDNode *From, 2175 const std::vector<SDOperand> &To, 2176 std::vector<SDNode*> *Deleted) { 2177 assert(From->getNumValues() == To.size() && 2178 "Incorrect number of values to replace with!"); 2179 if (To.size() == 1 && To[0].Val->getNumValues() == 1) { 2180 // Degenerate case handled above. 2181 ReplaceAllUsesWith(SDOperand(From, 0), To[0], Deleted); 2182 return; 2183 } 2184 2185 while (!From->use_empty()) { 2186 // Process users until they are all gone. 2187 SDNode *U = *From->use_begin(); 2188 2189 // This node is about to morph, remove its old self from the CSE maps. 2190 RemoveNodeFromCSEMaps(U); 2191 2192 for (unsigned i = 0, e = U->getNumOperands(); i != e; ++i) 2193 if (U->getOperand(i).Val == From) { 2194 const SDOperand &ToOp = To[U->getOperand(i).ResNo]; 2195 From->removeUser(U); 2196 U->Operands[i] = ToOp; 2197 ToOp.Val->addUser(U); 2198 } 2199 2200 // Now that we have modified U, add it back to the CSE maps. If it already 2201 // exists there, recursively merge the results together. 2202 if (SDNode *Existing = AddNonLeafNodeToCSEMaps(U)) { 2203 ReplaceAllUsesWith(U, Existing, Deleted); 2204 // U is now dead. 2205 if (Deleted) Deleted->push_back(U); 2206 DeleteNodeNotInCSEMaps(U); 2207 } 2208 } 2209} 2210 2211 2212//===----------------------------------------------------------------------===// 2213// SDNode Class 2214//===----------------------------------------------------------------------===// 2215 2216/// hasNUsesOfValue - Return true if there are exactly NUSES uses of the 2217/// indicated value. This method ignores uses of other values defined by this 2218/// operation. 2219bool SDNode::hasNUsesOfValue(unsigned NUses, unsigned Value) { 2220 assert(Value < getNumValues() && "Bad value!"); 2221 2222 // If there is only one value, this is easy. 2223 if (getNumValues() == 1) 2224 return use_size() == NUses; 2225 if (Uses.size() < NUses) return false; 2226 2227 SDOperand TheValue(this, Value); 2228 2229 std::set<SDNode*> UsersHandled; 2230 2231 for (std::vector<SDNode*>::iterator UI = Uses.begin(), E = Uses.end(); 2232 UI != E; ++UI) { 2233 SDNode *User = *UI; 2234 if (User->getNumOperands() == 1 || 2235 UsersHandled.insert(User).second) // First time we've seen this? 2236 for (unsigned i = 0, e = User->getNumOperands(); i != e; ++i) 2237 if (User->getOperand(i) == TheValue) { 2238 if (NUses == 0) 2239 return false; // too many uses 2240 --NUses; 2241 } 2242 } 2243 2244 // Found exactly the right number of uses? 2245 return NUses == 0; 2246} 2247 2248 2249const char *SDNode::getOperationName(const SelectionDAG *G) const { 2250 switch (getOpcode()) { 2251 default: 2252 if (getOpcode() < ISD::BUILTIN_OP_END) 2253 return "<<Unknown DAG Node>>"; 2254 else { 2255 if (G) 2256 if (const TargetInstrInfo *TII = G->getTarget().getInstrInfo()) 2257 return TII->getName(getOpcode()-ISD::BUILTIN_OP_END); 2258 return "<<Unknown Target Node>>"; 2259 } 2260 2261 case ISD::PCMARKER: return "PCMarker"; 2262 case ISD::SRCVALUE: return "SrcValue"; 2263 case ISD::VALUETYPE: return "ValueType"; 2264 case ISD::EntryToken: return "EntryToken"; 2265 case ISD::TokenFactor: return "TokenFactor"; 2266 case ISD::AssertSext: return "AssertSext"; 2267 case ISD::AssertZext: return "AssertZext"; 2268 case ISD::Constant: return "Constant"; 2269 case ISD::TargetConstant: return "TargetConstant"; 2270 case ISD::ConstantFP: return "ConstantFP"; 2271 case ISD::GlobalAddress: return "GlobalAddress"; 2272 case ISD::TargetGlobalAddress: return "TargetGlobalAddress"; 2273 case ISD::FrameIndex: return "FrameIndex"; 2274 case ISD::TargetFrameIndex: return "TargetFrameIndex"; 2275 case ISD::BasicBlock: return "BasicBlock"; 2276 case ISD::Register: return "Register"; 2277 case ISD::ExternalSymbol: return "ExternalSymbol"; 2278 case ISD::ConstantPool: return "ConstantPool"; 2279 case ISD::TargetConstantPool: return "TargetConstantPool"; 2280 case ISD::CopyToReg: return "CopyToReg"; 2281 case ISD::CopyFromReg: return "CopyFromReg"; 2282 case ISD::ImplicitDef: return "ImplicitDef"; 2283 case ISD::UNDEF: return "undef"; 2284 2285 // Unary operators 2286 case ISD::FABS: return "fabs"; 2287 case ISD::FNEG: return "fneg"; 2288 case ISD::FSQRT: return "fsqrt"; 2289 case ISD::FSIN: return "fsin"; 2290 case ISD::FCOS: return "fcos"; 2291 2292 // Binary operators 2293 case ISD::ADD: return "add"; 2294 case ISD::SUB: return "sub"; 2295 case ISD::MUL: return "mul"; 2296 case ISD::MULHU: return "mulhu"; 2297 case ISD::MULHS: return "mulhs"; 2298 case ISD::SDIV: return "sdiv"; 2299 case ISD::UDIV: return "udiv"; 2300 case ISD::SREM: return "srem"; 2301 case ISD::UREM: return "urem"; 2302 case ISD::AND: return "and"; 2303 case ISD::OR: return "or"; 2304 case ISD::XOR: return "xor"; 2305 case ISD::SHL: return "shl"; 2306 case ISD::SRA: return "sra"; 2307 case ISD::SRL: return "srl"; 2308 2309 case ISD::SETCC: return "setcc"; 2310 case ISD::SELECT: return "select"; 2311 case ISD::SELECT_CC: return "select_cc"; 2312 case ISD::ADD_PARTS: return "add_parts"; 2313 case ISD::SUB_PARTS: return "sub_parts"; 2314 case ISD::SHL_PARTS: return "shl_parts"; 2315 case ISD::SRA_PARTS: return "sra_parts"; 2316 case ISD::SRL_PARTS: return "srl_parts"; 2317 2318 // Conversion operators. 2319 case ISD::SIGN_EXTEND: return "sign_extend"; 2320 case ISD::ZERO_EXTEND: return "zero_extend"; 2321 case ISD::ANY_EXTEND: return "any_extend"; 2322 case ISD::SIGN_EXTEND_INREG: return "sign_extend_inreg"; 2323 case ISD::TRUNCATE: return "truncate"; 2324 case ISD::FP_ROUND: return "fp_round"; 2325 case ISD::FP_ROUND_INREG: return "fp_round_inreg"; 2326 case ISD::FP_EXTEND: return "fp_extend"; 2327 2328 case ISD::SINT_TO_FP: return "sint_to_fp"; 2329 case ISD::UINT_TO_FP: return "uint_to_fp"; 2330 case ISD::FP_TO_SINT: return "fp_to_sint"; 2331 case ISD::FP_TO_UINT: return "fp_to_uint"; 2332 2333 // Control flow instructions 2334 case ISD::BR: return "br"; 2335 case ISD::BRCOND: return "brcond"; 2336 case ISD::BRCONDTWOWAY: return "brcondtwoway"; 2337 case ISD::BR_CC: return "br_cc"; 2338 case ISD::BRTWOWAY_CC: return "brtwoway_cc"; 2339 case ISD::RET: return "ret"; 2340 case ISD::CALL: return "call"; 2341 case ISD::TAILCALL:return "tailcall"; 2342 case ISD::CALLSEQ_START: return "callseq_start"; 2343 case ISD::CALLSEQ_END: return "callseq_end"; 2344 2345 // Other operators 2346 case ISD::LOAD: return "load"; 2347 case ISD::STORE: return "store"; 2348 case ISD::EXTLOAD: return "extload"; 2349 case ISD::SEXTLOAD: return "sextload"; 2350 case ISD::ZEXTLOAD: return "zextload"; 2351 case ISD::TRUNCSTORE: return "truncstore"; 2352 2353 case ISD::DYNAMIC_STACKALLOC: return "dynamic_stackalloc"; 2354 case ISD::EXTRACT_ELEMENT: return "extract_element"; 2355 case ISD::BUILD_PAIR: return "build_pair"; 2356 case ISD::MEMSET: return "memset"; 2357 case ISD::MEMCPY: return "memcpy"; 2358 case ISD::MEMMOVE: return "memmove"; 2359 2360 // Bit counting 2361 case ISD::CTPOP: return "ctpop"; 2362 case ISD::CTTZ: return "cttz"; 2363 case ISD::CTLZ: return "ctlz"; 2364 2365 // IO Intrinsics 2366 case ISD::READPORT: return "readport"; 2367 case ISD::WRITEPORT: return "writeport"; 2368 case ISD::READIO: return "readio"; 2369 case ISD::WRITEIO: return "writeio"; 2370 2371 case ISD::CONDCODE: 2372 switch (cast<CondCodeSDNode>(this)->get()) { 2373 default: assert(0 && "Unknown setcc condition!"); 2374 case ISD::SETOEQ: return "setoeq"; 2375 case ISD::SETOGT: return "setogt"; 2376 case ISD::SETOGE: return "setoge"; 2377 case ISD::SETOLT: return "setolt"; 2378 case ISD::SETOLE: return "setole"; 2379 case ISD::SETONE: return "setone"; 2380 2381 case ISD::SETO: return "seto"; 2382 case ISD::SETUO: return "setuo"; 2383 case ISD::SETUEQ: return "setue"; 2384 case ISD::SETUGT: return "setugt"; 2385 case ISD::SETUGE: return "setuge"; 2386 case ISD::SETULT: return "setult"; 2387 case ISD::SETULE: return "setule"; 2388 case ISD::SETUNE: return "setune"; 2389 2390 case ISD::SETEQ: return "seteq"; 2391 case ISD::SETGT: return "setgt"; 2392 case ISD::SETGE: return "setge"; 2393 case ISD::SETLT: return "setlt"; 2394 case ISD::SETLE: return "setle"; 2395 case ISD::SETNE: return "setne"; 2396 } 2397 } 2398} 2399 2400void SDNode::dump() const { dump(0); } 2401void SDNode::dump(const SelectionDAG *G) const { 2402 std::cerr << (void*)this << ": "; 2403 2404 for (unsigned i = 0, e = getNumValues(); i != e; ++i) { 2405 if (i) std::cerr << ","; 2406 if (getValueType(i) == MVT::Other) 2407 std::cerr << "ch"; 2408 else 2409 std::cerr << MVT::getValueTypeString(getValueType(i)); 2410 } 2411 std::cerr << " = " << getOperationName(G); 2412 2413 std::cerr << " "; 2414 for (unsigned i = 0, e = getNumOperands(); i != e; ++i) { 2415 if (i) std::cerr << ", "; 2416 std::cerr << (void*)getOperand(i).Val; 2417 if (unsigned RN = getOperand(i).ResNo) 2418 std::cerr << ":" << RN; 2419 } 2420 2421 if (const ConstantSDNode *CSDN = dyn_cast<ConstantSDNode>(this)) { 2422 std::cerr << "<" << CSDN->getValue() << ">"; 2423 } else if (const ConstantFPSDNode *CSDN = dyn_cast<ConstantFPSDNode>(this)) { 2424 std::cerr << "<" << CSDN->getValue() << ">"; 2425 } else if (const GlobalAddressSDNode *GADN = 2426 dyn_cast<GlobalAddressSDNode>(this)) { 2427 std::cerr << "<"; 2428 WriteAsOperand(std::cerr, GADN->getGlobal()) << ">"; 2429 } else if (const FrameIndexSDNode *FIDN = dyn_cast<FrameIndexSDNode>(this)) { 2430 std::cerr << "<" << FIDN->getIndex() << ">"; 2431 } else if (const ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(this)){ 2432 std::cerr << "<" << *CP->get() << ">"; 2433 } else if (const BasicBlockSDNode *BBDN = dyn_cast<BasicBlockSDNode>(this)) { 2434 std::cerr << "<"; 2435 const Value *LBB = (const Value*)BBDN->getBasicBlock()->getBasicBlock(); 2436 if (LBB) 2437 std::cerr << LBB->getName() << " "; 2438 std::cerr << (const void*)BBDN->getBasicBlock() << ">"; 2439 } else if (const RegisterSDNode *R = dyn_cast<RegisterSDNode>(this)) { 2440 if (G && MRegisterInfo::isPhysicalRegister(R->getReg())) { 2441 std::cerr << " " <<G->getTarget().getRegisterInfo()->getName(R->getReg()); 2442 } else { 2443 std::cerr << " #" << R->getReg(); 2444 } 2445 } else if (const ExternalSymbolSDNode *ES = 2446 dyn_cast<ExternalSymbolSDNode>(this)) { 2447 std::cerr << "'" << ES->getSymbol() << "'"; 2448 } else if (const SrcValueSDNode *M = dyn_cast<SrcValueSDNode>(this)) { 2449 if (M->getValue()) 2450 std::cerr << "<" << M->getValue() << ":" << M->getOffset() << ">"; 2451 else 2452 std::cerr << "<null:" << M->getOffset() << ">"; 2453 } else if (const VTSDNode *N = dyn_cast<VTSDNode>(this)) { 2454 std::cerr << ":" << getValueTypeString(N->getVT()); 2455 } 2456} 2457 2458static void DumpNodes(SDNode *N, unsigned indent, const SelectionDAG *G) { 2459 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) 2460 if (N->getOperand(i).Val->hasOneUse()) 2461 DumpNodes(N->getOperand(i).Val, indent+2, G); 2462 else 2463 std::cerr << "\n" << std::string(indent+2, ' ') 2464 << (void*)N->getOperand(i).Val << ": <multiple use>"; 2465 2466 2467 std::cerr << "\n" << std::string(indent, ' '); 2468 N->dump(G); 2469} 2470 2471void SelectionDAG::dump() const { 2472 std::cerr << "SelectionDAG has " << AllNodes.size() << " nodes:"; 2473 std::vector<SDNode*> Nodes(AllNodes); 2474 std::sort(Nodes.begin(), Nodes.end()); 2475 2476 for (unsigned i = 0, e = Nodes.size(); i != e; ++i) { 2477 if (!Nodes[i]->hasOneUse() && Nodes[i] != getRoot().Val) 2478 DumpNodes(Nodes[i], 2, this); 2479 } 2480 2481 DumpNodes(getRoot().Val, 2, this); 2482 2483 std::cerr << "\n\n"; 2484} 2485 2486