SelectionDAG.cpp revision fd1f1ee0baf9c808fdee14bdbfe76d4a5e66210d
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/Target/TargetLowering.h" 20#include <iostream> 21#include <set> 22#include <cmath> 23#include <algorithm> 24using namespace llvm; 25 26static bool isCommutativeBinOp(unsigned Opcode) { 27 switch (Opcode) { 28 case ISD::ADD: 29 case ISD::MUL: 30 case ISD::AND: 31 case ISD::OR: 32 case ISD::XOR: return true; 33 default: return false; // FIXME: Need commutative info for user ops! 34 } 35} 36 37static bool isAssociativeBinOp(unsigned Opcode) { 38 switch (Opcode) { 39 case ISD::ADD: 40 case ISD::MUL: 41 case ISD::AND: 42 case ISD::OR: 43 case ISD::XOR: return true; 44 default: return false; // FIXME: Need associative info for user ops! 45 } 46} 47 48static unsigned ExactLog2(uint64_t Val) { 49 unsigned Count = 0; 50 while (Val != 1) { 51 Val >>= 1; 52 ++Count; 53 } 54 return Count; 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 (isa<SetCCSDNode>(N.Val) && N.Val->hasOneUse()) 62 return true; 63 return false; 64} 65 66 67/// getSetCCSwappedOperands - Return the operation corresponding to (Y op X) 68/// when given the operation for (X op Y). 69ISD::CondCode ISD::getSetCCSwappedOperands(ISD::CondCode Operation) { 70 // To perform this operation, we just need to swap the L and G bits of the 71 // operation. 72 unsigned OldL = (Operation >> 2) & 1; 73 unsigned OldG = (Operation >> 1) & 1; 74 return ISD::CondCode((Operation & ~6) | // Keep the N, U, E bits 75 (OldL << 1) | // New G bit 76 (OldG << 2)); // New L bit. 77} 78 79/// getSetCCInverse - Return the operation corresponding to !(X op Y), where 80/// 'op' is a valid SetCC operation. 81ISD::CondCode ISD::getSetCCInverse(ISD::CondCode Op, bool isInteger) { 82 unsigned Operation = Op; 83 if (isInteger) 84 Operation ^= 7; // Flip L, G, E bits, but not U. 85 else 86 Operation ^= 15; // Flip all of the condition bits. 87 if (Operation > ISD::SETTRUE2) 88 Operation &= ~8; // Don't let N and U bits get set. 89 return ISD::CondCode(Operation); 90} 91 92 93/// isSignedOp - For an integer comparison, return 1 if the comparison is a 94/// signed operation and 2 if the result is an unsigned comparison. Return zero 95/// if the operation does not depend on the sign of the input (setne and seteq). 96static int isSignedOp(ISD::CondCode Opcode) { 97 switch (Opcode) { 98 default: assert(0 && "Illegal integer setcc operation!"); 99 case ISD::SETEQ: 100 case ISD::SETNE: return 0; 101 case ISD::SETLT: 102 case ISD::SETLE: 103 case ISD::SETGT: 104 case ISD::SETGE: return 1; 105 case ISD::SETULT: 106 case ISD::SETULE: 107 case ISD::SETUGT: 108 case ISD::SETUGE: return 2; 109 } 110} 111 112/// getSetCCOrOperation - Return the result of a logical OR between different 113/// comparisons of identical values: ((X op1 Y) | (X op2 Y)). This function 114/// returns SETCC_INVALID if it is not possible to represent the resultant 115/// comparison. 116ISD::CondCode ISD::getSetCCOrOperation(ISD::CondCode Op1, ISD::CondCode Op2, 117 bool isInteger) { 118 if (isInteger && (isSignedOp(Op1) | isSignedOp(Op2)) == 3) 119 // Cannot fold a signed integer setcc with an unsigned integer setcc. 120 return ISD::SETCC_INVALID; 121 122 unsigned Op = Op1 | Op2; // Combine all of the condition bits. 123 124 // If the N and U bits get set then the resultant comparison DOES suddenly 125 // care about orderedness, and is true when ordered. 126 if (Op > ISD::SETTRUE2) 127 Op &= ~16; // Clear the N bit. 128 return ISD::CondCode(Op); 129} 130 131/// getSetCCAndOperation - Return the result of a logical AND between different 132/// comparisons of identical values: ((X op1 Y) & (X op2 Y)). This 133/// function returns zero if it is not possible to represent the resultant 134/// comparison. 135ISD::CondCode ISD::getSetCCAndOperation(ISD::CondCode Op1, ISD::CondCode Op2, 136 bool isInteger) { 137 if (isInteger && (isSignedOp(Op1) | isSignedOp(Op2)) == 3) 138 // Cannot fold a signed setcc with an unsigned setcc. 139 return ISD::SETCC_INVALID; 140 141 // Combine all of the condition bits. 142 return ISD::CondCode(Op1 & Op2); 143} 144 145const TargetMachine &SelectionDAG::getTarget() const { 146 return TLI.getTargetMachine(); 147} 148 149 150/// RemoveDeadNodes - This method deletes all unreachable nodes in the 151/// SelectionDAG, including nodes (like loads) that have uses of their token 152/// chain but no other uses and no side effect. If a node is passed in as an 153/// argument, it is used as the seed for node deletion. 154void SelectionDAG::RemoveDeadNodes(SDNode *N) { 155 std::set<SDNode*> AllNodeSet(AllNodes.begin(), AllNodes.end()); 156 157 // Create a dummy node (which is not added to allnodes), that adds a reference 158 // to the root node, preventing it from being deleted. 159 SDNode *DummyNode = new SDNode(ISD::EntryToken, getRoot()); 160 161 DeleteNodeIfDead(N, &AllNodeSet); 162 163 Restart: 164 unsigned NumNodes = AllNodeSet.size(); 165 for (std::set<SDNode*>::iterator I = AllNodeSet.begin(), E = AllNodeSet.end(); 166 I != E; ++I) { 167 // Try to delete this node. 168 DeleteNodeIfDead(*I, &AllNodeSet); 169 170 // If we actually deleted any nodes, do not use invalid iterators in 171 // AllNodeSet. 172 if (AllNodeSet.size() != NumNodes) 173 goto Restart; 174 } 175 176 // Restore AllNodes. 177 if (AllNodes.size() != NumNodes) 178 AllNodes.assign(AllNodeSet.begin(), AllNodeSet.end()); 179 180 // If the root changed (e.g. it was a dead load, update the root). 181 setRoot(DummyNode->getOperand(0)); 182 183 // Now that we are done with the dummy node, delete it. 184 DummyNode->getOperand(0).Val->removeUser(DummyNode); 185 delete DummyNode; 186} 187 188void SelectionDAG::DeleteNodeIfDead(SDNode *N, void *NodeSet) { 189 if (!N->use_empty()) 190 return; 191 192 // Okay, we really are going to delete this node. First take this out of the 193 // appropriate CSE map. 194 switch (N->getOpcode()) { 195 case ISD::Constant: 196 Constants.erase(std::make_pair(cast<ConstantSDNode>(N)->getValue(), 197 N->getValueType(0))); 198 break; 199 case ISD::ConstantFP: { 200 union { 201 double DV; 202 uint64_t IV; 203 }; 204 DV = cast<ConstantFPSDNode>(N)->getValue(); 205 ConstantFPs.erase(std::make_pair(IV, N->getValueType(0))); 206 break; 207 } 208 case ISD::GlobalAddress: 209 GlobalValues.erase(cast<GlobalAddressSDNode>(N)->getGlobal()); 210 break; 211 case ISD::FrameIndex: 212 FrameIndices.erase(cast<FrameIndexSDNode>(N)->getIndex()); 213 break; 214 case ISD::ConstantPool: 215 ConstantPoolIndices.erase(cast<ConstantPoolSDNode>(N)->getIndex()); 216 break; 217 case ISD::BasicBlock: 218 BBNodes.erase(cast<BasicBlockSDNode>(N)->getBasicBlock()); 219 break; 220 case ISD::ExternalSymbol: 221 ExternalSymbols.erase(cast<ExternalSymbolSDNode>(N)->getSymbol()); 222 break; 223 224 case ISD::LOAD: 225 Loads.erase(std::make_pair(N->getOperand(1), 226 std::make_pair(N->getOperand(0), 227 N->getValueType(0)))); 228 break; 229 case ISD::SETCC: 230 SetCCs.erase(std::make_pair(std::make_pair(N->getOperand(0), 231 N->getOperand(1)), 232 std::make_pair( 233 cast<SetCCSDNode>(N)->getCondition(), 234 N->getValueType(0)))); 235 break; 236 case ISD::TRUNCSTORE: 237 case ISD::SIGN_EXTEND_INREG: 238 case ISD::ZERO_EXTEND_INREG: 239 case ISD::FP_ROUND_INREG: 240 case ISD::EXTLOAD: 241 case ISD::SEXTLOAD: 242 case ISD::ZEXTLOAD: { 243 EVTStruct NN; 244 NN.Opcode = N->getOpcode(); 245 NN.VT = N->getValueType(0); 246 NN.EVT = cast<MVTSDNode>(N)->getExtraValueType(); 247 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) 248 NN.Ops.push_back(N->getOperand(i)); 249 MVTSDNodes.erase(NN); 250 break; 251 } 252 default: 253 if (N->getNumOperands() == 1) 254 UnaryOps.erase(std::make_pair(N->getOpcode(), 255 std::make_pair(N->getOperand(0), 256 N->getValueType(0)))); 257 else if (N->getNumOperands() == 2) 258 BinaryOps.erase(std::make_pair(N->getOpcode(), 259 std::make_pair(N->getOperand(0), 260 N->getOperand(1)))); 261 break; 262 } 263 264 // Next, brutally remove the operand list. 265 while (!N->Operands.empty()) { 266 SDNode *O = N->Operands.back().Val; 267 N->Operands.pop_back(); 268 O->removeUser(N); 269 270 // Now that we removed this operand, see if there are no uses of it left. 271 DeleteNodeIfDead(O, NodeSet); 272 } 273 274 // Remove the node from the nodes set and delete it. 275 std::set<SDNode*> &AllNodeSet = *(std::set<SDNode*>*)NodeSet; 276 AllNodeSet.erase(N); 277 278 // Now that the node is gone, check to see if any of the operands of this node 279 // are dead now. 280 delete N; 281} 282 283 284SelectionDAG::~SelectionDAG() { 285 for (unsigned i = 0, e = AllNodes.size(); i != e; ++i) 286 delete AllNodes[i]; 287} 288 289SDOperand SelectionDAG::getConstant(uint64_t Val, MVT::ValueType VT) { 290 assert(MVT::isInteger(VT) && "Cannot create FP integer constant!"); 291 // Mask out any bits that are not valid for this constant. 292 if (VT != MVT::i64) 293 Val &= ((uint64_t)1 << MVT::getSizeInBits(VT)) - 1; 294 295 SDNode *&N = Constants[std::make_pair(Val, VT)]; 296 if (N) return SDOperand(N, 0); 297 N = new ConstantSDNode(Val, VT); 298 AllNodes.push_back(N); 299 return SDOperand(N, 0); 300} 301 302SDOperand SelectionDAG::getConstantFP(double Val, MVT::ValueType VT) { 303 assert(MVT::isFloatingPoint(VT) && "Cannot create integer FP constant!"); 304 if (VT == MVT::f32) 305 Val = (float)Val; // Mask out extra precision. 306 307 // Do the map lookup using the actual bit pattern for the floating point 308 // value, so that we don't have problems with 0.0 comparing equal to -0.0, and 309 // we don't have issues with SNANs. 310 union { 311 double DV; 312 uint64_t IV; 313 }; 314 315 DV = Val; 316 317 SDNode *&N = ConstantFPs[std::make_pair(IV, VT)]; 318 if (N) return SDOperand(N, 0); 319 N = new ConstantFPSDNode(Val, VT); 320 AllNodes.push_back(N); 321 return SDOperand(N, 0); 322} 323 324 325 326SDOperand SelectionDAG::getGlobalAddress(const GlobalValue *GV, 327 MVT::ValueType VT) { 328 SDNode *&N = GlobalValues[GV]; 329 if (N) return SDOperand(N, 0); 330 N = new GlobalAddressSDNode(GV,VT); 331 AllNodes.push_back(N); 332 return SDOperand(N, 0); 333} 334 335SDOperand SelectionDAG::getFrameIndex(int FI, MVT::ValueType VT) { 336 SDNode *&N = FrameIndices[FI]; 337 if (N) return SDOperand(N, 0); 338 N = new FrameIndexSDNode(FI, VT); 339 AllNodes.push_back(N); 340 return SDOperand(N, 0); 341} 342 343SDOperand SelectionDAG::getConstantPool(unsigned CPIdx, MVT::ValueType VT) { 344 SDNode *N = ConstantPoolIndices[CPIdx]; 345 if (N) return SDOperand(N, 0); 346 N = new ConstantPoolSDNode(CPIdx, VT); 347 AllNodes.push_back(N); 348 return SDOperand(N, 0); 349} 350 351SDOperand SelectionDAG::getBasicBlock(MachineBasicBlock *MBB) { 352 SDNode *&N = BBNodes[MBB]; 353 if (N) return SDOperand(N, 0); 354 N = new BasicBlockSDNode(MBB); 355 AllNodes.push_back(N); 356 return SDOperand(N, 0); 357} 358 359SDOperand SelectionDAG::getExternalSymbol(const char *Sym, MVT::ValueType VT) { 360 SDNode *&N = ExternalSymbols[Sym]; 361 if (N) return SDOperand(N, 0); 362 N = new ExternalSymbolSDNode(Sym, VT); 363 AllNodes.push_back(N); 364 return SDOperand(N, 0); 365} 366 367SDOperand SelectionDAG::getSetCC(ISD::CondCode Cond, MVT::ValueType VT, 368 SDOperand N1, SDOperand N2) { 369 // These setcc operations always fold. 370 switch (Cond) { 371 default: break; 372 case ISD::SETFALSE: 373 case ISD::SETFALSE2: return getConstant(0, VT); 374 case ISD::SETTRUE: 375 case ISD::SETTRUE2: return getConstant(1, VT); 376 } 377 378 if (ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2.Val)) { 379 uint64_t C2 = N2C->getValue(); 380 if (ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.Val)) { 381 uint64_t C1 = N1C->getValue(); 382 383 // Sign extend the operands if required 384 if (ISD::isSignedIntSetCC(Cond)) { 385 C1 = N1C->getSignExtended(); 386 C2 = N2C->getSignExtended(); 387 } 388 389 switch (Cond) { 390 default: assert(0 && "Unknown integer setcc!"); 391 case ISD::SETEQ: return getConstant(C1 == C2, VT); 392 case ISD::SETNE: return getConstant(C1 != C2, VT); 393 case ISD::SETULT: return getConstant(C1 < C2, VT); 394 case ISD::SETUGT: return getConstant(C1 > C2, VT); 395 case ISD::SETULE: return getConstant(C1 <= C2, VT); 396 case ISD::SETUGE: return getConstant(C1 >= C2, VT); 397 case ISD::SETLT: return getConstant((int64_t)C1 < (int64_t)C2, VT); 398 case ISD::SETGT: return getConstant((int64_t)C1 > (int64_t)C2, VT); 399 case ISD::SETLE: return getConstant((int64_t)C1 <= (int64_t)C2, VT); 400 case ISD::SETGE: return getConstant((int64_t)C1 >= (int64_t)C2, VT); 401 } 402 } else { 403 uint64_t MinVal, MaxVal; 404 unsigned OperandBitSize = MVT::getSizeInBits(N2C->getValueType(0)); 405 if (ISD::isSignedIntSetCC(Cond)) { 406 MinVal = 1ULL << (OperandBitSize-1); 407 if (OperandBitSize != 1) // Avoid X >> 64, which is undefined. 408 MaxVal = ~0ULL >> (65-OperandBitSize); 409 else 410 MaxVal = 0; 411 } else { 412 MinVal = 0; 413 MaxVal = ~0ULL >> (64-OperandBitSize); 414 } 415 416 // Canonicalize GE/LE comparisons to use GT/LT comparisons. 417 if (Cond == ISD::SETGE || Cond == ISD::SETUGE) { 418 if (C2 == MinVal) return getConstant(1, VT); // X >= MIN --> true 419 --C2; // X >= C1 --> X > (C1-1) 420 Cond = (Cond == ISD::SETGE) ? ISD::SETGT : ISD::SETUGT; 421 N2 = getConstant(C2, N2.getValueType()); 422 N2C = cast<ConstantSDNode>(N2.Val); 423 } 424 425 if (Cond == ISD::SETLE || Cond == ISD::SETULE) { 426 if (C2 == MaxVal) return getConstant(1, VT); // X <= MAX --> true 427 ++C2; // X <= C1 --> X < (C1+1) 428 Cond = (Cond == ISD::SETLE) ? ISD::SETLT : ISD::SETULT; 429 N2 = getConstant(C2, N2.getValueType()); 430 N2C = cast<ConstantSDNode>(N2.Val); 431 } 432 433 // If we have setult X, 1, turn it into seteq X, 0 434 if ((Cond == ISD::SETLT || Cond == ISD::SETULT) && C2 == MinVal+1) 435 return getSetCC(ISD::SETEQ, VT, N1, 436 getConstant(MinVal, N1.getValueType())); 437 // If we have setult X, 1, turn it into seteq X, 0 438 else if ((Cond == ISD::SETGT || Cond == ISD::SETUGT) && C2 == MaxVal-1) 439 return getSetCC(ISD::SETEQ, VT, N1, 440 getConstant(MaxVal, N1.getValueType())); 441 442 // If we have "setcc X, C1", check to see if we can shrink the immediate 443 // by changing cc. 444 445 // SETUGT X, SINTMAX -> SETLT X, 0 446 if (Cond == ISD::SETUGT && OperandBitSize != 1 && 447 C2 == (~0ULL >> (65-OperandBitSize))) 448 return getSetCC(ISD::SETLT, VT, N1, getConstant(0, N2.getValueType())); 449 450 // FIXME: Implement the rest of these. 451 452 } 453 } else if (isa<ConstantSDNode>(N1.Val)) { 454 // Ensure that the constant occurs on the RHS. 455 return getSetCC(ISD::getSetCCSwappedOperands(Cond), VT, N2, N1); 456 } 457 458 if (ConstantFPSDNode *N1C = dyn_cast<ConstantFPSDNode>(N1.Val)) 459 if (ConstantFPSDNode *N2C = dyn_cast<ConstantFPSDNode>(N2.Val)) { 460 double C1 = N1C->getValue(), C2 = N2C->getValue(); 461 462 switch (Cond) { 463 default: break; // FIXME: Implement the rest of these! 464 case ISD::SETEQ: return getConstant(C1 == C2, VT); 465 case ISD::SETNE: return getConstant(C1 != C2, VT); 466 case ISD::SETLT: return getConstant(C1 < C2, VT); 467 case ISD::SETGT: return getConstant(C1 > C2, VT); 468 case ISD::SETLE: return getConstant(C1 <= C2, VT); 469 case ISD::SETGE: return getConstant(C1 >= C2, VT); 470 } 471 } else { 472 // Ensure that the constant occurs on the RHS. 473 Cond = ISD::getSetCCSwappedOperands(Cond); 474 std::swap(N1, N2); 475 } 476 477 if (N1 == N2) { 478 // We can always fold X == Y for integer setcc's. 479 if (MVT::isInteger(N1.getValueType())) 480 return getConstant(ISD::isTrueWhenEqual(Cond), VT); 481 unsigned UOF = ISD::getUnorderedFlavor(Cond); 482 if (UOF == 2) // FP operators that are undefined on NaNs. 483 return getConstant(ISD::isTrueWhenEqual(Cond), VT); 484 if (UOF == ISD::isTrueWhenEqual(Cond)) 485 return getConstant(UOF, VT); 486 // Otherwise, we can't fold it. However, we can simplify it to SETUO/SETO 487 // if it is not already. 488 Cond = UOF == 0 ? ISD::SETUO : ISD::SETO; 489 } 490 491 if ((Cond == ISD::SETEQ || Cond == ISD::SETNE) && 492 MVT::isInteger(N1.getValueType())) { 493 if (N1.getOpcode() == ISD::ADD || N1.getOpcode() == ISD::SUB || 494 N1.getOpcode() == ISD::XOR) { 495 // Simplify (X+Y) == (X+Z) --> Y == Z 496 if (N1.getOpcode() == N2.getOpcode()) { 497 if (N1.getOperand(0) == N2.getOperand(0)) 498 return getSetCC(Cond, VT, N1.getOperand(1), N2.getOperand(1)); 499 if (N1.getOperand(1) == N2.getOperand(1)) 500 return getSetCC(Cond, VT, N1.getOperand(0), N2.getOperand(0)); 501 if (isCommutativeBinOp(N1.getOpcode())) { 502 // If X op Y == Y op X, try other combinations. 503 if (N1.getOperand(0) == N2.getOperand(1)) 504 return getSetCC(Cond, VT, N1.getOperand(1), N2.getOperand(0)); 505 if (N1.getOperand(1) == N2.getOperand(0)) 506 return getSetCC(Cond, VT, N1.getOperand(1), N2.getOperand(1)); 507 } 508 } 509 510 // FIXME: move this stuff to the DAG Combiner when it exists! 511 512 // Simplify (X+Z) == X --> Z == 0 513 if (N1.getOperand(0) == N2) 514 return getSetCC(Cond, VT, N1.getOperand(1), 515 getConstant(0, N1.getValueType())); 516 if (N1.getOperand(1) == N2) { 517 if (isCommutativeBinOp(N1.getOpcode())) 518 return getSetCC(Cond, VT, N1.getOperand(0), 519 getConstant(0, N1.getValueType())); 520 else { 521 assert(N1.getOpcode() == ISD::SUB && "Unexpected operation!"); 522 // (Z-X) == X --> Z == X<<1 523 return getSetCC(Cond, VT, N1.getOperand(0), 524 getNode(ISD::SHL, N2.getValueType(), 525 N2, getConstant(1, TLI.getShiftAmountTy()))); 526 } 527 } 528 } 529 530 if (N2.getOpcode() == ISD::ADD || N2.getOpcode() == ISD::SUB || 531 N2.getOpcode() == ISD::XOR) { 532 // Simplify X == (X+Z) --> Z == 0 533 if (N2.getOperand(0) == N1) 534 return getSetCC(Cond, VT, N2.getOperand(1), 535 getConstant(0, N2.getValueType())); 536 else if (N2.getOperand(1) == N1) 537 return getSetCC(Cond, VT, N2.getOperand(0), 538 getConstant(0, N2.getValueType())); 539 } 540 } 541 542 SetCCSDNode *&N = SetCCs[std::make_pair(std::make_pair(N1, N2), 543 std::make_pair(Cond, VT))]; 544 if (N) return SDOperand(N, 0); 545 N = new SetCCSDNode(Cond, N1, N2); 546 N->setValueTypes(VT); 547 AllNodes.push_back(N); 548 return SDOperand(N, 0); 549} 550 551 552 553/// getNode - Gets or creates the specified node. 554/// 555SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT) { 556 SDNode *N = new SDNode(Opcode, VT); 557 AllNodes.push_back(N); 558 return SDOperand(N, 0); 559} 560 561SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, 562 SDOperand Operand) { 563 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Operand.Val)) { 564 uint64_t Val = C->getValue(); 565 switch (Opcode) { 566 default: break; 567 case ISD::SIGN_EXTEND: return getConstant(C->getSignExtended(), VT); 568 case ISD::ZERO_EXTEND: return getConstant(Val, VT); 569 case ISD::TRUNCATE: return getConstant(Val, VT); 570 case ISD::SINT_TO_FP: return getConstantFP(C->getSignExtended(), VT); 571 case ISD::UINT_TO_FP: return getConstantFP(C->getValue(), VT); 572 } 573 } 574 575 if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Operand.Val)) 576 switch (Opcode) { 577 case ISD::FNEG: 578 return getConstantFP(-C->getValue(), VT); 579 case ISD::FP_ROUND: 580 case ISD::FP_EXTEND: 581 return getConstantFP(C->getValue(), VT); 582 case ISD::FP_TO_SINT: 583 return getConstant((int64_t)C->getValue(), VT); 584 case ISD::FP_TO_UINT: 585 return getConstant((uint64_t)C->getValue(), VT); 586 } 587 588 unsigned OpOpcode = Operand.Val->getOpcode(); 589 switch (Opcode) { 590 case ISD::TokenFactor: 591 return Operand; // Factor of one node? No factor. 592 case ISD::SIGN_EXTEND: 593 if (Operand.getValueType() == VT) return Operand; // noop extension 594 if (OpOpcode == ISD::SIGN_EXTEND || OpOpcode == ISD::ZERO_EXTEND) 595 return getNode(OpOpcode, VT, Operand.Val->getOperand(0)); 596 break; 597 case ISD::ZERO_EXTEND: 598 if (Operand.getValueType() == VT) return Operand; // noop extension 599 if (OpOpcode == ISD::ZERO_EXTEND) // (zext (zext x)) -> (zext x) 600 return getNode(ISD::ZERO_EXTEND, VT, Operand.Val->getOperand(0)); 601 break; 602 case ISD::TRUNCATE: 603 if (Operand.getValueType() == VT) return Operand; // noop truncate 604 if (OpOpcode == ISD::TRUNCATE) 605 return getNode(ISD::TRUNCATE, VT, Operand.Val->getOperand(0)); 606 else if (OpOpcode == ISD::ZERO_EXTEND || OpOpcode == ISD::SIGN_EXTEND) { 607 // If the source is smaller than the dest, we still need an extend. 608 if (Operand.Val->getOperand(0).getValueType() < VT) 609 return getNode(OpOpcode, VT, Operand.Val->getOperand(0)); 610 else if (Operand.Val->getOperand(0).getValueType() > VT) 611 return getNode(ISD::TRUNCATE, VT, Operand.Val->getOperand(0)); 612 else 613 return Operand.Val->getOperand(0); 614 } 615 break; 616 case ISD::FNEG: 617 if (OpOpcode == ISD::SUB) // -(X-Y) -> (Y-X) 618 return getNode(ISD::SUB, VT, Operand.Val->getOperand(1), 619 Operand.Val->getOperand(0)); 620 if (OpOpcode == ISD::FNEG) // --X -> X 621 return Operand.Val->getOperand(0); 622 break; 623 case ISD::FABS: 624 if (OpOpcode == ISD::FNEG) // abs(-X) -> abs(X) 625 return getNode(ISD::FABS, VT, Operand.Val->getOperand(0)); 626 break; 627 } 628 629 SDNode *&N = UnaryOps[std::make_pair(Opcode, std::make_pair(Operand, VT))]; 630 if (N) return SDOperand(N, 0); 631 N = new SDNode(Opcode, Operand); 632 N->setValueTypes(VT); 633 AllNodes.push_back(N); 634 return SDOperand(N, 0); 635} 636 637SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, 638 SDOperand N1, SDOperand N2) { 639#ifndef NDEBUG 640 switch (Opcode) { 641 case ISD::TokenFactor: 642 assert(VT == MVT::Other && N1.getValueType() == MVT::Other && 643 N2.getValueType() == MVT::Other && "Invalid token factor!"); 644 break; 645 case ISD::AND: 646 case ISD::OR: 647 case ISD::XOR: 648 case ISD::UDIV: 649 case ISD::UREM: 650 assert(MVT::isInteger(VT) && "This operator does not apply to FP types!"); 651 // fall through 652 case ISD::ADD: 653 case ISD::SUB: 654 case ISD::MUL: 655 case ISD::SDIV: 656 case ISD::SREM: 657 assert(N1.getValueType() == N2.getValueType() && 658 N1.getValueType() == VT && "Binary operator types must match!"); 659 break; 660 661 case ISD::SHL: 662 case ISD::SRA: 663 case ISD::SRL: 664 assert(VT == N1.getValueType() && 665 "Shift operators return type must be the same as their first arg"); 666 assert(MVT::isInteger(VT) && MVT::isInteger(N2.getValueType()) && 667 VT != MVT::i1 && "Shifts only work on integers"); 668 break; 669 default: break; 670 } 671#endif 672 673 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.Val); 674 ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2.Val); 675 if (N1C) { 676 if (N2C) { 677 uint64_t C1 = N1C->getValue(), C2 = N2C->getValue(); 678 switch (Opcode) { 679 case ISD::ADD: return getConstant(C1 + C2, VT); 680 case ISD::SUB: return getConstant(C1 - C2, VT); 681 case ISD::MUL: return getConstant(C1 * C2, VT); 682 case ISD::UDIV: 683 if (C2) return getConstant(C1 / C2, VT); 684 break; 685 case ISD::UREM : 686 if (C2) return getConstant(C1 % C2, VT); 687 break; 688 case ISD::SDIV : 689 if (C2) return getConstant(N1C->getSignExtended() / 690 N2C->getSignExtended(), VT); 691 break; 692 case ISD::SREM : 693 if (C2) return getConstant(N1C->getSignExtended() % 694 N2C->getSignExtended(), VT); 695 break; 696 case ISD::AND : return getConstant(C1 & C2, VT); 697 case ISD::OR : return getConstant(C1 | C2, VT); 698 case ISD::XOR : return getConstant(C1 ^ C2, VT); 699 case ISD::SHL : return getConstant(C1 << (int)C2, VT); 700 case ISD::SRL : return getConstant(C1 >> (unsigned)C2, VT); 701 case ISD::SRA : return getConstant(N1C->getSignExtended() >>(int)C2, VT); 702 default: break; 703 } 704 705 } else { // Cannonicalize constant to RHS if commutative 706 if (isCommutativeBinOp(Opcode)) { 707 std::swap(N1C, N2C); 708 std::swap(N1, N2); 709 } 710 } 711 712 switch (Opcode) { 713 default: break; 714 case ISD::SHL: // shl 0, X -> 0 715 if (N1C->isNullValue()) return N1; 716 break; 717 case ISD::SRL: // srl 0, X -> 0 718 if (N1C->isNullValue()) return N1; 719 break; 720 case ISD::SRA: // sra -1, X -> -1 721 if (N1C->isAllOnesValue()) return N1; 722 break; 723 } 724 } 725 726 if (N2C) { 727 uint64_t C2 = N2C->getValue(); 728 729 switch (Opcode) { 730 case ISD::ADD: 731 if (!C2) return N1; // add X, 0 -> X 732 break; 733 case ISD::SUB: 734 if (!C2) return N1; // sub X, 0 -> X 735 break; 736 case ISD::MUL: 737 if (!C2) return N2; // mul X, 0 -> 0 738 if (N2C->isAllOnesValue()) // mul X, -1 -> 0-X 739 return getNode(ISD::SUB, VT, getConstant(0, VT), N1); 740 741 // FIXME: Move this to the DAG combiner when it exists. 742 if ((C2 & C2-1) == 0) { 743 SDOperand ShAmt = getConstant(ExactLog2(C2), TLI.getShiftAmountTy()); 744 return getNode(ISD::SHL, VT, N1, ShAmt); 745 } 746 break; 747 748 case ISD::UDIV: 749 // FIXME: Move this to the DAG combiner when it exists. 750 if ((C2 & C2-1) == 0 && C2) { 751 SDOperand ShAmt = getConstant(ExactLog2(C2), TLI.getShiftAmountTy()); 752 return getNode(ISD::SRL, VT, N1, ShAmt); 753 } 754 break; 755 756 case ISD::SHL: 757 case ISD::SRL: 758 // If the shift amount is bigger than the size of the data, simplify. 759 if (C2 >= MVT::getSizeInBits(N1.getValueType())) { 760 if (TLI.getShiftAmountFlavor() == TargetLowering::Mask) { 761 unsigned NewAmt = 762 C2 & ((1 << MVT::getSizeInBits(N1.getValueType()))-1); 763 return getNode(Opcode, VT, N1, getConstant(NewAmt,N2.getValueType())); 764 } else if (TLI.getShiftAmountFlavor() == TargetLowering::Extend) { 765 // Shifting all of the bits out? 766 return getConstant(0, N1.getValueType()); 767 } 768 } 769 // FALL THROUGH. 770 case ISD::SRA: 771 if (C2 == 0) return N1; 772 break; 773 774 case ISD::AND: 775 if (!C2) return N2; // X and 0 -> 0 776 if (N2C->isAllOnesValue()) 777 return N1; // X and -1 -> X 778 779 // FIXME: Should add a corresponding version of this for 780 // ZERO_EXTEND/SIGN_EXTEND by converting them to an ANY_EXTEND node which 781 // we don't have yet. 782 783 // and (zero_extend_inreg x:16:32), 1 -> and x, 1 784 if (N1.getOpcode() == ISD::ZERO_EXTEND_INREG || 785 N1.getOpcode() == ISD::SIGN_EXTEND_INREG) { 786 // If we are masking out the part of our input that was extended, just 787 // mask the input to the extension directly. 788 unsigned ExtendBits = 789 MVT::getSizeInBits(cast<MVTSDNode>(N1)->getExtraValueType()); 790 if ((C2 & (~0ULL << ExtendBits)) == 0) 791 return getNode(ISD::AND, VT, N1.getOperand(0), N2); 792 } 793 break; 794 case ISD::OR: 795 if (!C2)return N1; // X or 0 -> X 796 if (N2C->isAllOnesValue()) 797 return N2; // X or -1 -> -1 798 break; 799 case ISD::XOR: 800 if (!C2) return N1; // X xor 0 -> X 801 if (N2C->isAllOnesValue()) { 802 if (SetCCSDNode *SetCC = dyn_cast<SetCCSDNode>(N1.Val)){ 803 // !(X op Y) -> (X !op Y) 804 bool isInteger = MVT::isInteger(SetCC->getOperand(0).getValueType()); 805 return getSetCC(ISD::getSetCCInverse(SetCC->getCondition(),isInteger), 806 SetCC->getValueType(0), 807 SetCC->getOperand(0), SetCC->getOperand(1)); 808 } else if (N1.getOpcode() == ISD::AND || N1.getOpcode() == ISD::OR) { 809 SDNode *Op = N1.Val; 810 // !(X or Y) -> (!X and !Y) iff X or Y are freely invertible 811 // !(X and Y) -> (!X or !Y) iff X or Y are freely invertible 812 SDOperand LHS = Op->getOperand(0), RHS = Op->getOperand(1); 813 if (isInvertibleForFree(RHS) || isInvertibleForFree(LHS)) { 814 LHS = getNode(ISD::XOR, VT, LHS, N2); // RHS = ~LHS 815 RHS = getNode(ISD::XOR, VT, RHS, N2); // RHS = ~RHS 816 if (Op->getOpcode() == ISD::AND) 817 return getNode(ISD::OR, VT, LHS, RHS); 818 return getNode(ISD::AND, VT, LHS, RHS); 819 } 820 } 821 // X xor -1 -> not(x) ? 822 } 823 break; 824 } 825 826 // Reassociate ((X op C1) op C2) if possible. 827 if (N1.getOpcode() == Opcode && isAssociativeBinOp(Opcode)) 828 if (ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N1.Val->getOperand(1))) 829 return getNode(Opcode, VT, N1.Val->getOperand(0), 830 getNode(Opcode, VT, N2, N1.Val->getOperand(1))); 831 } 832 833 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1.Val); 834 ConstantFPSDNode *N2CFP = dyn_cast<ConstantFPSDNode>(N2.Val); 835 if (N1CFP) 836 if (N2CFP) { 837 double C1 = N1CFP->getValue(), C2 = N2CFP->getValue(); 838 switch (Opcode) { 839 case ISD::ADD: return getConstantFP(C1 + C2, VT); 840 case ISD::SUB: return getConstantFP(C1 - C2, VT); 841 case ISD::MUL: return getConstantFP(C1 * C2, VT); 842 case ISD::SDIV: 843 if (C2) return getConstantFP(C1 / C2, VT); 844 break; 845 case ISD::SREM : 846 if (C2) return getConstantFP(fmod(C1, C2), VT); 847 break; 848 default: break; 849 } 850 851 } else { // Cannonicalize constant to RHS if commutative 852 if (isCommutativeBinOp(Opcode)) { 853 std::swap(N1CFP, N2CFP); 854 std::swap(N1, N2); 855 } 856 } 857 858 // Finally, fold operations that do not require constants. 859 switch (Opcode) { 860 case ISD::TokenFactor: 861 if (N1.getOpcode() == ISD::EntryToken) 862 return N2; 863 if (N2.getOpcode() == ISD::EntryToken) 864 return N1; 865 break; 866 867 case ISD::AND: 868 case ISD::OR: 869 if (SetCCSDNode *LHS = dyn_cast<SetCCSDNode>(N1.Val)) 870 if (SetCCSDNode *RHS = dyn_cast<SetCCSDNode>(N2.Val)) { 871 SDOperand LL = LHS->getOperand(0), RL = RHS->getOperand(0); 872 SDOperand LR = LHS->getOperand(1), RR = RHS->getOperand(1); 873 ISD::CondCode Op2 = RHS->getCondition(); 874 875 // (X op1 Y) | (Y op2 X) -> (X op1 Y) | (X swapop2 Y) 876 if (LL == RR && LR == RL) { 877 Op2 = ISD::getSetCCSwappedOperands(Op2); 878 goto MatchedBackwards; 879 } 880 881 if (LL == RL && LR == RR) { 882 MatchedBackwards: 883 ISD::CondCode Result; 884 bool isInteger = MVT::isInteger(LL.getValueType()); 885 if (Opcode == ISD::OR) 886 Result = ISD::getSetCCOrOperation(LHS->getCondition(), Op2, 887 isInteger); 888 else 889 Result = ISD::getSetCCAndOperation(LHS->getCondition(), Op2, 890 isInteger); 891 if (Result != ISD::SETCC_INVALID) 892 return getSetCC(Result, LHS->getValueType(0), LL, LR); 893 } 894 } 895 break; 896 case ISD::XOR: 897 if (N1 == N2) return getConstant(0, VT); // xor X, Y -> 0 898 break; 899 case ISD::ADD: 900 if (N2.getOpcode() == ISD::FNEG) // (A+ (-B) -> A-B 901 return getNode(ISD::SUB, VT, N1, N2.getOperand(0)); 902 if (N1.getOpcode() == ISD::FNEG) // ((-A)+B) -> B-A 903 return getNode(ISD::SUB, VT, N2, N1.getOperand(0)); 904 if (N1.getOpcode() == ISD::SUB && isa<ConstantSDNode>(N1.getOperand(0)) && 905 cast<ConstantSDNode>(N1.getOperand(0))->getValue() == 0) 906 return getNode(ISD::SUB, VT, N2, N1.getOperand(1)); // (0-A)+B -> B-A 907 if (N2.getOpcode() == ISD::SUB && isa<ConstantSDNode>(N2.getOperand(0)) && 908 cast<ConstantSDNode>(N2.getOperand(0))->getValue() == 0) 909 return getNode(ISD::SUB, VT, N1, N2.getOperand(1)); // A+(0-B) -> A-B 910 break; 911 case ISD::SUB: 912 if (N1.getOpcode() == ISD::ADD) { 913 if (N1.Val->getOperand(0) == N2) 914 return N1.Val->getOperand(1); // (A+B)-A == B 915 if (N1.Val->getOperand(1) == N2) 916 return N1.Val->getOperand(0); // (A+B)-B == A 917 } 918 if (N2.getOpcode() == ISD::FNEG) // (A- (-B) -> A+B 919 return getNode(ISD::ADD, VT, N1, N2.getOperand(0)); 920 break; 921 } 922 923 SDNode *&N = BinaryOps[std::make_pair(Opcode, std::make_pair(N1, N2))]; 924 if (N) return SDOperand(N, 0); 925 N = new SDNode(Opcode, N1, N2); 926 N->setValueTypes(VT); 927 928 AllNodes.push_back(N); 929 return SDOperand(N, 0); 930} 931 932SDOperand SelectionDAG::getLoad(MVT::ValueType VT, 933 SDOperand Chain, SDOperand Ptr) { 934 SDNode *&N = Loads[std::make_pair(Ptr, std::make_pair(Chain, VT))]; 935 if (N) return SDOperand(N, 0); 936 N = new SDNode(ISD::LOAD, Chain, Ptr); 937 938 // Loads have a token chain. 939 N->setValueTypes(VT, MVT::Other); 940 AllNodes.push_back(N); 941 return SDOperand(N, 0); 942} 943 944 945SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, 946 SDOperand N1, SDOperand N2, SDOperand N3) { 947 // Perform various simplifications. 948 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.Val); 949 ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2.Val); 950 ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N3.Val); 951 switch (Opcode) { 952 case ISD::SELECT: 953 if (N1C) 954 if (N1C->getValue()) 955 return N2; // select true, X, Y -> X 956 else 957 return N3; // select false, X, Y -> Y 958 959 if (N2 == N3) return N2; // select C, X, X -> X 960 961 if (VT == MVT::i1) { // Boolean SELECT 962 if (N2C) { 963 if (N2C->getValue()) // select C, 1, X -> C | X 964 return getNode(ISD::OR, VT, N1, N3); 965 else // select C, 0, X -> ~C & X 966 return getNode(ISD::AND, VT, 967 getNode(ISD::XOR, N1.getValueType(), N1, 968 getConstant(1, N1.getValueType())), N3); 969 } else if (N3C) { 970 if (N3C->getValue()) // select C, X, 1 -> ~C | X 971 return getNode(ISD::OR, VT, 972 getNode(ISD::XOR, N1.getValueType(), N1, 973 getConstant(1, N1.getValueType())), N2); 974 else // select C, X, 0 -> C & X 975 return getNode(ISD::AND, VT, N1, N2); 976 } 977 978 if (N1 == N2) // X ? X : Y --> X ? 1 : Y --> X | Y 979 return getNode(ISD::OR, VT, N1, N3); 980 if (N1 == N3) // X ? Y : X --> X ? Y : 0 --> X & Y 981 return getNode(ISD::AND, VT, N1, N2); 982 } 983 984 // If this is a selectcc, check to see if we can simplify the result. 985 if (SetCCSDNode *SetCC = dyn_cast<SetCCSDNode>(N1)) { 986 if (ConstantFPSDNode *CFP = 987 dyn_cast<ConstantFPSDNode>(SetCC->getOperand(1))) 988 if (CFP->getValue() == 0.0) { // Allow either -0.0 or 0.0 989 // select (setg[te] X, +/-0.0), X, fneg(X) -> fabs 990 if ((SetCC->getCondition() == ISD::SETGE || 991 SetCC->getCondition() == ISD::SETGT) && 992 N2 == SetCC->getOperand(0) && N3.getOpcode() == ISD::FNEG && 993 N3.getOperand(0) == N2) 994 return getNode(ISD::FABS, VT, N2); 995 996 // select (setl[te] X, +/-0.0), fneg(X), X -> fabs 997 if ((SetCC->getCondition() == ISD::SETLT || 998 SetCC->getCondition() == ISD::SETLE) && 999 N3 == SetCC->getOperand(0) && N2.getOpcode() == ISD::FNEG && 1000 N2.getOperand(0) == N3) 1001 return getNode(ISD::FABS, VT, N3); 1002 } 1003 } 1004 break; 1005 case ISD::BRCOND: 1006 if (N2C) 1007 if (N2C->getValue()) // Unconditional branch 1008 return getNode(ISD::BR, MVT::Other, N1, N3); 1009 else 1010 return N1; // Never-taken branch 1011 break; 1012 } 1013 1014 SDNode *N = new SDNode(Opcode, N1, N2, N3); 1015 switch (Opcode) { 1016 default: 1017 N->setValueTypes(VT); 1018 break; 1019 case ISD::DYNAMIC_STACKALLOC: // DYNAMIC_STACKALLOC produces pointer and chain 1020 N->setValueTypes(VT, MVT::Other); 1021 break; 1022 1023 case ISD::SRA_PARTS: 1024 case ISD::SRL_PARTS: 1025 case ISD::SHL_PARTS: { 1026 std::vector<MVT::ValueType> V(N->getNumOperands()-1, VT); 1027 N->setValueTypes(V); 1028 break; 1029 } 1030 } 1031 1032 // FIXME: memoize NODES 1033 AllNodes.push_back(N); 1034 return SDOperand(N, 0); 1035} 1036 1037SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, 1038 std::vector<SDOperand> &Children) { 1039 switch (Children.size()) { 1040 case 0: return getNode(Opcode, VT); 1041 case 1: return getNode(Opcode, VT, Children[0]); 1042 case 2: return getNode(Opcode, VT, Children[0], Children[1]); 1043 case 3: return getNode(Opcode, VT, Children[0], Children[1], Children[2]); 1044 default: break; 1045 } 1046 1047 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(Children[1].Val); 1048 switch (Opcode) { 1049 default: break; 1050 case ISD::BRCONDTWOWAY: 1051 if (N1C) 1052 if (N1C->getValue()) // Unconditional branch to true dest. 1053 return getNode(ISD::BR, MVT::Other, Children[0], Children[2]); 1054 else // Unconditional branch to false dest. 1055 return getNode(ISD::BR, MVT::Other, Children[0], Children[3]); 1056 break; 1057 } 1058 1059 // FIXME: MEMOIZE!! 1060 SDNode *N = new SDNode(Opcode, Children); 1061 if (Opcode != ISD::ADD_PARTS && Opcode != ISD::SUB_PARTS) { 1062 N->setValueTypes(VT); 1063 } else { 1064 std::vector<MVT::ValueType> V(N->getNumOperands()/2, VT); 1065 N->setValueTypes(V); 1066 } 1067 AllNodes.push_back(N); 1068 return SDOperand(N, 0); 1069} 1070 1071SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT,SDOperand N1, 1072 MVT::ValueType EVT) { 1073 1074 switch (Opcode) { 1075 default: assert(0 && "Bad opcode for this accessor!"); 1076 case ISD::FP_ROUND_INREG: 1077 assert(VT == N1.getValueType() && "Not an inreg round!"); 1078 assert(MVT::isFloatingPoint(VT) && MVT::isFloatingPoint(EVT) && 1079 "Cannot FP_ROUND_INREG integer types"); 1080 if (EVT == VT) return N1; // Not actually rounding 1081 assert(EVT < VT && "Not rounding down!"); 1082 1083 if (isa<ConstantFPSDNode>(N1)) 1084 return getNode(ISD::FP_EXTEND, VT, getNode(ISD::FP_ROUND, EVT, N1)); 1085 break; 1086 case ISD::ZERO_EXTEND_INREG: 1087 case ISD::SIGN_EXTEND_INREG: 1088 assert(VT == N1.getValueType() && "Not an inreg extend!"); 1089 assert(MVT::isInteger(VT) && MVT::isInteger(EVT) && 1090 "Cannot *_EXTEND_INREG FP types"); 1091 if (EVT == VT) return N1; // Not actually extending 1092 assert(EVT < VT && "Not extending!"); 1093 1094 // Extending a constant? Just return the constant. 1095 if (ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.Val)) { 1096 SDOperand Tmp = getNode(ISD::TRUNCATE, EVT, N1); 1097 if (Opcode == ISD::ZERO_EXTEND_INREG) 1098 return getNode(ISD::ZERO_EXTEND, VT, Tmp); 1099 else 1100 return getNode(ISD::SIGN_EXTEND, VT, Tmp); 1101 } 1102 1103 // If we are sign extending an extension, use the original source. 1104 if (N1.getOpcode() == ISD::ZERO_EXTEND_INREG || 1105 N1.getOpcode() == ISD::SIGN_EXTEND_INREG) { 1106 if (N1.getOpcode() == Opcode && 1107 cast<MVTSDNode>(N1)->getExtraValueType() <= EVT) 1108 return N1; 1109 } 1110 1111 // If we are (zero|sign) extending a [zs]extload, return just the load. 1112 if ((N1.getOpcode() == ISD::ZEXTLOAD && Opcode == ISD::ZERO_EXTEND_INREG) || 1113 (N1.getOpcode() == ISD::SEXTLOAD && Opcode == ISD::SIGN_EXTEND_INREG)) 1114 if (cast<MVTSDNode>(N1)->getExtraValueType() <= EVT) 1115 return N1; 1116 1117 // If we are extending the result of a setcc, and we already know the 1118 // contents of the top bits, eliminate the extension. 1119 if (N1.getOpcode() == ISD::SETCC) 1120 switch (TLI.getSetCCResultContents()) { 1121 case TargetLowering::UndefinedSetCCResult: break; 1122 case TargetLowering::ZeroOrOneSetCCResult: 1123 if (Opcode == ISD::ZERO_EXTEND_INREG) return N1; 1124 break; 1125 case TargetLowering::ZeroOrNegativeOneSetCCResult: 1126 if (Opcode == ISD::SIGN_EXTEND_INREG) return N1; 1127 break; 1128 } 1129 1130 // If we are sign extending the result of an (and X, C) operation, and we 1131 // know the extended bits are zeros already, don't do the extend. 1132 if (N1.getOpcode() == ISD::AND) 1133 if (ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getOperand(1))) { 1134 uint64_t Mask = N1C->getValue(); 1135 unsigned NumBits = MVT::getSizeInBits(EVT); 1136 if (Opcode == ISD::ZERO_EXTEND_INREG) { 1137 if ((Mask & (~0ULL << NumBits)) == 0) 1138 return N1; 1139 else 1140 return getNode(ISD::AND, VT, N1.getOperand(0), 1141 getConstant(Mask & (~0ULL >> (64-NumBits)), VT)); 1142 } else { 1143 assert(Opcode == ISD::SIGN_EXTEND_INREG); 1144 if ((Mask & (~0ULL << (NumBits-1))) == 0) 1145 return N1; 1146 } 1147 } 1148 break; 1149 } 1150 1151 EVTStruct NN; 1152 NN.Opcode = Opcode; 1153 NN.VT = VT; 1154 NN.EVT = EVT; 1155 NN.Ops.push_back(N1); 1156 1157 SDNode *&N = MVTSDNodes[NN]; 1158 if (N) return SDOperand(N, 0); 1159 N = new MVTSDNode(Opcode, VT, N1, EVT); 1160 AllNodes.push_back(N); 1161 return SDOperand(N, 0); 1162} 1163 1164SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT,SDOperand N1, 1165 SDOperand N2, MVT::ValueType EVT) { 1166 switch (Opcode) { 1167 default: assert(0 && "Bad opcode for this accessor!"); 1168 case ISD::EXTLOAD: 1169 case ISD::SEXTLOAD: 1170 case ISD::ZEXTLOAD: 1171 // If they are asking for an extending loat from/to the same thing, return a 1172 // normal load. 1173 if (VT == EVT) 1174 return getNode(ISD::LOAD, VT, N1, N2); 1175 assert(EVT < VT && "Should only be an extending load, not truncating!"); 1176 assert((Opcode == ISD::EXTLOAD || MVT::isInteger(VT)) && 1177 "Cannot sign/zero extend a FP load!"); 1178 assert(MVT::isInteger(VT) == MVT::isInteger(EVT) && 1179 "Cannot convert from FP to Int or Int -> FP!"); 1180 break; 1181 } 1182 1183 EVTStruct NN; 1184 NN.Opcode = Opcode; 1185 NN.VT = VT; 1186 NN.EVT = EVT; 1187 NN.Ops.push_back(N1); 1188 NN.Ops.push_back(N2); 1189 1190 SDNode *&N = MVTSDNodes[NN]; 1191 if (N) return SDOperand(N, 0); 1192 N = new MVTSDNode(Opcode, VT, MVT::Other, N1, N2, EVT); 1193 AllNodes.push_back(N); 1194 return SDOperand(N, 0); 1195} 1196 1197SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT,SDOperand N1, 1198 SDOperand N2, SDOperand N3, MVT::ValueType EVT) { 1199 switch (Opcode) { 1200 default: assert(0 && "Bad opcode for this accessor!"); 1201 case ISD::TRUNCSTORE: 1202#if 0 // FIXME: If the target supports EVT natively, convert to a truncate/store 1203 // If this is a truncating store of a constant, convert to the desired type 1204 // and store it instead. 1205 if (isa<Constant>(N1)) { 1206 SDOperand Op = getNode(ISD::TRUNCATE, EVT, N1); 1207 if (isa<Constant>(Op)) 1208 N1 = Op; 1209 } 1210 // Also for ConstantFP? 1211#endif 1212 if (N1.getValueType() == EVT) // Normal store? 1213 return getNode(ISD::STORE, VT, N1, N2, N3); 1214 assert(N2.getValueType() > EVT && "Not a truncation?"); 1215 assert(MVT::isInteger(N2.getValueType()) == MVT::isInteger(EVT) && 1216 "Can't do FP-INT conversion!"); 1217 break; 1218 } 1219 1220 EVTStruct NN; 1221 NN.Opcode = Opcode; 1222 NN.VT = VT; 1223 NN.EVT = EVT; 1224 NN.Ops.push_back(N1); 1225 NN.Ops.push_back(N2); 1226 NN.Ops.push_back(N3); 1227 1228 SDNode *&N = MVTSDNodes[NN]; 1229 if (N) return SDOperand(N, 0); 1230 N = new MVTSDNode(Opcode, VT, N1, N2, N3, EVT); 1231 AllNodes.push_back(N); 1232 return SDOperand(N, 0); 1233} 1234 1235 1236/// hasNUsesOfValue - Return true if there are exactly NUSES uses of the 1237/// indicated value. This method ignores uses of other values defined by this 1238/// operation. 1239bool SDNode::hasNUsesOfValue(unsigned NUses, unsigned Value) { 1240 assert(Value < getNumValues() && "Bad value!"); 1241 1242 // If there is only one value, this is easy. 1243 if (getNumValues() == 1) 1244 return use_size() == NUses; 1245 if (Uses.size() < NUses) return false; 1246 1247 SDOperand TheValue(this, Value); 1248 1249 std::set<SDNode*> UsersHandled; 1250 1251 for (std::vector<SDNode*>::iterator UI = Uses.begin(), E = Uses.end(); 1252 UI != E; ++UI) { 1253 SDNode *User = *UI; 1254 if (User->getNumOperands() == 1 || 1255 UsersHandled.insert(User).second) // First time we've seen this? 1256 for (unsigned i = 0, e = User->getNumOperands(); i != e; ++i) 1257 if (User->getOperand(i) == TheValue) { 1258 if (NUses == 0) 1259 return false; // too many uses 1260 --NUses; 1261 } 1262 } 1263 1264 // Found exactly the right number of uses? 1265 return NUses == 0; 1266} 1267 1268 1269const char *SDNode::getOperationName() const { 1270 switch (getOpcode()) { 1271 default: return "<<Unknown>>"; 1272 case ISD::PCMARKER: return "PCMarker"; 1273 case ISD::EntryToken: return "EntryToken"; 1274 case ISD::TokenFactor: return "TokenFactor"; 1275 case ISD::Constant: return "Constant"; 1276 case ISD::ConstantFP: return "ConstantFP"; 1277 case ISD::GlobalAddress: return "GlobalAddress"; 1278 case ISD::FrameIndex: return "FrameIndex"; 1279 case ISD::BasicBlock: return "BasicBlock"; 1280 case ISD::ExternalSymbol: return "ExternalSymbol"; 1281 case ISD::ConstantPool: return "ConstantPoolIndex"; 1282 case ISD::CopyToReg: return "CopyToReg"; 1283 case ISD::CopyFromReg: return "CopyFromReg"; 1284 case ISD::ImplicitDef: return "ImplicitDef"; 1285 case ISD::UNDEF: return "undef"; 1286 1287 // Unary operators 1288 case ISD::FABS: return "fabs"; 1289 case ISD::FNEG: return "fneg"; 1290 1291 // Binary operators 1292 case ISD::ADD: return "add"; 1293 case ISD::SUB: return "sub"; 1294 case ISD::MUL: return "mul"; 1295 case ISD::MULHU: return "mulhu"; 1296 case ISD::MULHS: return "mulhs"; 1297 case ISD::SDIV: return "sdiv"; 1298 case ISD::UDIV: return "udiv"; 1299 case ISD::SREM: return "srem"; 1300 case ISD::UREM: return "urem"; 1301 case ISD::AND: return "and"; 1302 case ISD::OR: return "or"; 1303 case ISD::XOR: return "xor"; 1304 case ISD::SHL: return "shl"; 1305 case ISD::SRA: return "sra"; 1306 case ISD::SRL: return "srl"; 1307 1308 case ISD::SELECT: return "select"; 1309 case ISD::ADD_PARTS: return "add_parts"; 1310 case ISD::SUB_PARTS: return "sub_parts"; 1311 case ISD::SHL_PARTS: return "shl_parts"; 1312 case ISD::SRA_PARTS: return "sra_parts"; 1313 case ISD::SRL_PARTS: return "srl_parts"; 1314 1315 // Conversion operators. 1316 case ISD::SIGN_EXTEND: return "sign_extend"; 1317 case ISD::ZERO_EXTEND: return "zero_extend"; 1318 case ISD::SIGN_EXTEND_INREG: return "sign_extend_inreg"; 1319 case ISD::ZERO_EXTEND_INREG: return "zero_extend_inreg"; 1320 case ISD::TRUNCATE: return "truncate"; 1321 case ISD::FP_ROUND: return "fp_round"; 1322 case ISD::FP_ROUND_INREG: return "fp_round_inreg"; 1323 case ISD::FP_EXTEND: return "fp_extend"; 1324 1325 case ISD::SINT_TO_FP: return "sint_to_fp"; 1326 case ISD::UINT_TO_FP: return "uint_to_fp"; 1327 case ISD::FP_TO_SINT: return "fp_to_sint"; 1328 case ISD::FP_TO_UINT: return "fp_to_uint"; 1329 1330 // Control flow instructions 1331 case ISD::BR: return "br"; 1332 case ISD::BRCOND: return "brcond"; 1333 case ISD::BRCONDTWOWAY: return "brcondtwoway"; 1334 case ISD::RET: return "ret"; 1335 case ISD::CALL: return "call"; 1336 case ISD::ADJCALLSTACKDOWN: return "adjcallstackdown"; 1337 case ISD::ADJCALLSTACKUP: return "adjcallstackup"; 1338 1339 // Other operators 1340 case ISD::LOAD: return "load"; 1341 case ISD::STORE: return "store"; 1342 case ISD::EXTLOAD: return "extload"; 1343 case ISD::SEXTLOAD: return "sextload"; 1344 case ISD::ZEXTLOAD: return "zextload"; 1345 case ISD::TRUNCSTORE: return "truncstore"; 1346 1347 case ISD::DYNAMIC_STACKALLOC: return "dynamic_stackalloc"; 1348 case ISD::EXTRACT_ELEMENT: return "extract_element"; 1349 case ISD::BUILD_PAIR: return "build_pair"; 1350 case ISD::MEMSET: return "memset"; 1351 case ISD::MEMCPY: return "memcpy"; 1352 case ISD::MEMMOVE: return "memmove"; 1353 1354 case ISD::SETCC: 1355 const SetCCSDNode *SetCC = cast<SetCCSDNode>(this); 1356 switch (SetCC->getCondition()) { 1357 default: assert(0 && "Unknown setcc condition!"); 1358 case ISD::SETOEQ: return "setcc:setoeq"; 1359 case ISD::SETOGT: return "setcc:setogt"; 1360 case ISD::SETOGE: return "setcc:setoge"; 1361 case ISD::SETOLT: return "setcc:setolt"; 1362 case ISD::SETOLE: return "setcc:setole"; 1363 case ISD::SETONE: return "setcc:setone"; 1364 1365 case ISD::SETO: return "setcc:seto"; 1366 case ISD::SETUO: return "setcc:setuo"; 1367 case ISD::SETUEQ: return "setcc:setue"; 1368 case ISD::SETUGT: return "setcc:setugt"; 1369 case ISD::SETUGE: return "setcc:setuge"; 1370 case ISD::SETULT: return "setcc:setult"; 1371 case ISD::SETULE: return "setcc:setule"; 1372 case ISD::SETUNE: return "setcc:setune"; 1373 1374 case ISD::SETEQ: return "setcc:seteq"; 1375 case ISD::SETGT: return "setcc:setgt"; 1376 case ISD::SETGE: return "setcc:setge"; 1377 case ISD::SETLT: return "setcc:setlt"; 1378 case ISD::SETLE: return "setcc:setle"; 1379 case ISD::SETNE: return "setcc:setne"; 1380 } 1381 } 1382} 1383 1384void SDNode::dump() const { 1385 std::cerr << (void*)this << ": "; 1386 1387 for (unsigned i = 0, e = getNumValues(); i != e; ++i) { 1388 if (i) std::cerr << ","; 1389 if (getValueType(i) == MVT::Other) 1390 std::cerr << "ch"; 1391 else 1392 std::cerr << MVT::getValueTypeString(getValueType(i)); 1393 } 1394 std::cerr << " = " << getOperationName(); 1395 1396 std::cerr << " "; 1397 for (unsigned i = 0, e = getNumOperands(); i != e; ++i) { 1398 if (i) std::cerr << ", "; 1399 std::cerr << (void*)getOperand(i).Val; 1400 if (unsigned RN = getOperand(i).ResNo) 1401 std::cerr << ":" << RN; 1402 } 1403 1404 if (const ConstantSDNode *CSDN = dyn_cast<ConstantSDNode>(this)) { 1405 std::cerr << "<" << CSDN->getValue() << ">"; 1406 } else if (const ConstantFPSDNode *CSDN = dyn_cast<ConstantFPSDNode>(this)) { 1407 std::cerr << "<" << CSDN->getValue() << ">"; 1408 } else if (const GlobalAddressSDNode *GADN = 1409 dyn_cast<GlobalAddressSDNode>(this)) { 1410 std::cerr << "<"; 1411 WriteAsOperand(std::cerr, GADN->getGlobal()) << ">"; 1412 } else if (const FrameIndexSDNode *FIDN = 1413 dyn_cast<FrameIndexSDNode>(this)) { 1414 std::cerr << "<" << FIDN->getIndex() << ">"; 1415 } else if (const ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(this)){ 1416 std::cerr << "<" << CP->getIndex() << ">"; 1417 } else if (const BasicBlockSDNode *BBDN = 1418 dyn_cast<BasicBlockSDNode>(this)) { 1419 std::cerr << "<"; 1420 const Value *LBB = (const Value*)BBDN->getBasicBlock()->getBasicBlock(); 1421 if (LBB) 1422 std::cerr << LBB->getName() << " "; 1423 std::cerr << (const void*)BBDN->getBasicBlock() << ">"; 1424 } else if (const RegSDNode *C2V = dyn_cast<RegSDNode>(this)) { 1425 std::cerr << "<reg #" << C2V->getReg() << ">"; 1426 } else if (const ExternalSymbolSDNode *ES = 1427 dyn_cast<ExternalSymbolSDNode>(this)) { 1428 std::cerr << "'" << ES->getSymbol() << "'"; 1429 } else if (const MVTSDNode *M = dyn_cast<MVTSDNode>(this)) { 1430 std::cerr << " - Ty = " << MVT::getValueTypeString(M->getExtraValueType()); 1431 } 1432} 1433 1434static void DumpNodes(SDNode *N, unsigned indent) { 1435 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) 1436 if (N->getOperand(i).Val->hasOneUse()) 1437 DumpNodes(N->getOperand(i).Val, indent+2); 1438 else 1439 std::cerr << "\n" << std::string(indent+2, ' ') 1440 << (void*)N->getOperand(i).Val << ": <multiple use>"; 1441 1442 1443 std::cerr << "\n" << std::string(indent, ' '); 1444 N->dump(); 1445} 1446 1447void SelectionDAG::dump() const { 1448 std::cerr << "SelectionDAG has " << AllNodes.size() << " nodes:"; 1449 std::vector<SDNode*> Nodes(AllNodes); 1450 std::sort(Nodes.begin(), Nodes.end()); 1451 1452 for (unsigned i = 0, e = Nodes.size(); i != e; ++i) { 1453 if (!Nodes[i]->hasOneUse() && Nodes[i] != getRoot().Val) 1454 DumpNodes(Nodes[i], 2); 1455 } 1456 1457 DumpNodes(getRoot().Val, 2); 1458 1459 std::cerr << "\n\n"; 1460} 1461 1462