LegalizeTypesGeneric.cpp revision 4e8982a34da69effe23ce9c553680b19d7d57551
1//===-------- LegalizeTypesGeneric.cpp - Generic type legalization --------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements generic type expansion and splitting for LegalizeTypes. 11// The routines here perform legalization when the details of the type (such as 12// whether it is an integer or a float) do not matter. 13// Expansion is the act of changing a computation in an illegal type to be a 14// computation in two identical registers of a smaller type. The Lo/Hi part 15// is required to be stored first in memory on little/big-endian machines. 16// Splitting is the act of changing a computation in an illegal type to be a 17// computation in two not necessarily identical registers of a smaller type. 18// There are no requirements on how the type is represented in memory. 19// 20//===----------------------------------------------------------------------===// 21 22#include "LegalizeTypes.h" 23#include "llvm/Target/TargetData.h" 24using namespace llvm; 25 26//===----------------------------------------------------------------------===// 27// Generic Result Expansion. 28//===----------------------------------------------------------------------===// 29 30// These routines assume that the Lo/Hi part is stored first in memory on 31// little/big-endian machines, followed by the Hi/Lo part. This means that 32// they cannot be used as is on vectors, for which Lo is always stored first. 33void DAGTypeLegalizer::ExpandRes_MERGE_VALUES(SDNode *N, unsigned ResNo, 34 SDValue &Lo, SDValue &Hi) { 35 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo); 36 GetExpandedOp(Op, Lo, Hi); 37} 38 39void DAGTypeLegalizer::ExpandRes_BITCAST(SDNode *N, SDValue &Lo, SDValue &Hi) { 40 EVT OutVT = N->getValueType(0); 41 EVT NOutVT = TLI.getTypeToTransformTo(*DAG.getContext(), OutVT); 42 SDValue InOp = N->getOperand(0); 43 EVT InVT = InOp.getValueType(); 44 DebugLoc dl = N->getDebugLoc(); 45 46 // Handle some special cases efficiently. 47 switch (getTypeAction(InVT)) { 48 case TargetLowering::TypeLegal: 49 case TargetLowering::TypePromoteInteger: 50 break; 51 case TargetLowering::TypeSoftenFloat: 52 // Convert the integer operand instead. 53 SplitInteger(GetSoftenedFloat(InOp), Lo, Hi); 54 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo); 55 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi); 56 return; 57 case TargetLowering::TypeExpandInteger: 58 case TargetLowering::TypeExpandFloat: 59 // Convert the expanded pieces of the input. 60 GetExpandedOp(InOp, Lo, Hi); 61 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo); 62 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi); 63 return; 64 case TargetLowering::TypeSplitVector: 65 GetSplitVector(InOp, Lo, Hi); 66 if (TLI.isBigEndian()) 67 std::swap(Lo, Hi); 68 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo); 69 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi); 70 return; 71 case TargetLowering::TypeScalarizeVector: 72 // Convert the element instead. 73 SplitInteger(BitConvertToInteger(GetScalarizedVector(InOp)), Lo, Hi); 74 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo); 75 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi); 76 return; 77 case TargetLowering::TypeWidenVector: { 78 assert(!(InVT.getVectorNumElements() & 1) && "Unsupported BITCAST"); 79 InOp = GetWidenedVector(InOp); 80 EVT InNVT = EVT::getVectorVT(*DAG.getContext(), InVT.getVectorElementType(), 81 InVT.getVectorNumElements()/2); 82 Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, InOp, 83 DAG.getIntPtrConstant(0)); 84 Hi = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, InOp, 85 DAG.getIntPtrConstant(InNVT.getVectorNumElements())); 86 if (TLI.isBigEndian()) 87 std::swap(Lo, Hi); 88 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo); 89 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi); 90 return; 91 } 92 } 93 94 if (InVT.isVector() && OutVT.isInteger()) { 95 // Handle cases like i64 = BITCAST v1i64 on x86, where the operand 96 // is legal but the result is not. 97 EVT NVT = EVT::getVectorVT(*DAG.getContext(), NOutVT, 2); 98 99 if (isTypeLegal(NVT)) { 100 SDValue CastInOp = DAG.getNode(ISD::BITCAST, dl, NVT, InOp); 101 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp, 102 DAG.getIntPtrConstant(0)); 103 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp, 104 DAG.getIntPtrConstant(1)); 105 106 if (TLI.isBigEndian()) 107 std::swap(Lo, Hi); 108 109 return; 110 } 111 } 112 113 // Lower the bit-convert to a store/load from the stack. 114 assert(NOutVT.isByteSized() && "Expanded type not byte sized!"); 115 116 // Create the stack frame object. Make sure it is aligned for both 117 // the source and expanded destination types. 118 unsigned Alignment = 119 TLI.getTargetData()->getPrefTypeAlignment(NOutVT. 120 getTypeForEVT(*DAG.getContext())); 121 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment); 122 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex(); 123 MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI); 124 125 // Emit a store to the stack slot. 126 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, PtrInfo, 127 false, false, 0); 128 129 // Load the first half from the stack slot. 130 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, PtrInfo, 131 false, false, false, 0); 132 133 // Increment the pointer to the other half. 134 unsigned IncrementSize = NOutVT.getSizeInBits() / 8; 135 StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr, 136 DAG.getIntPtrConstant(IncrementSize)); 137 138 // Load the second half from the stack slot. 139 Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr, 140 PtrInfo.getWithOffset(IncrementSize), false, 141 false, false, MinAlign(Alignment, IncrementSize)); 142 143 // Handle endianness of the load. 144 if (TLI.isBigEndian()) 145 std::swap(Lo, Hi); 146} 147 148void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo, 149 SDValue &Hi) { 150 // Return the operands. 151 Lo = N->getOperand(0); 152 Hi = N->getOperand(1); 153} 154 155void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo, 156 SDValue &Hi) { 157 GetExpandedOp(N->getOperand(0), Lo, Hi); 158 SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? 159 Hi : Lo; 160 161 assert(Part.getValueType() == N->getValueType(0) && 162 "Type twice as big as expanded type not itself expanded!"); 163 164 GetPairElements(Part, Lo, Hi); 165} 166 167void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo, 168 SDValue &Hi) { 169 SDValue OldVec = N->getOperand(0); 170 unsigned OldElts = OldVec.getValueType().getVectorNumElements(); 171 EVT OldEltVT = OldVec.getValueType().getVectorElementType(); 172 DebugLoc dl = N->getDebugLoc(); 173 174 // Convert to a vector of the expanded element type, for example 175 // <3 x i64> -> <6 x i32>. 176 EVT OldVT = N->getValueType(0); 177 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT); 178 179 if (OldVT != OldEltVT) { 180 // The result of EXTRACT_VECTOR_ELT may be larger than the element type of 181 // the input vector. If so, extend the elements of the input vector to the 182 // same bitwidth as the result before expanding. 183 assert(OldEltVT.bitsLT(OldVT) && "Result type smaller then element type!"); 184 EVT NVecVT = EVT::getVectorVT(*DAG.getContext(), OldVT, OldElts); 185 OldVec = DAG.getNode(ISD::ANY_EXTEND, dl, NVecVT, N->getOperand(0)); 186 } 187 188 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl, 189 EVT::getVectorVT(*DAG.getContext(), 190 NewVT, 2*OldElts), 191 OldVec); 192 193 // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector. 194 SDValue Idx = N->getOperand(1); 195 196 // Make sure the type of Idx is big enough to hold the new values. 197 if (Idx.getValueType().bitsLT(TLI.getPointerTy())) 198 Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx); 199 200 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx); 201 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx); 202 203 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, 204 DAG.getConstant(1, Idx.getValueType())); 205 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx); 206 207 if (TLI.isBigEndian()) 208 std::swap(Lo, Hi); 209} 210 211void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo, 212 SDValue &Hi) { 213 assert(ISD::isNormalLoad(N) && "This routine only for normal loads!"); 214 DebugLoc dl = N->getDebugLoc(); 215 216 LoadSDNode *LD = cast<LoadSDNode>(N); 217 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), LD->getValueType(0)); 218 SDValue Chain = LD->getChain(); 219 SDValue Ptr = LD->getBasePtr(); 220 unsigned Alignment = LD->getAlignment(); 221 bool isVolatile = LD->isVolatile(); 222 bool isNonTemporal = LD->isNonTemporal(); 223 bool isInvariant = LD->isInvariant(); 224 225 assert(NVT.isByteSized() && "Expanded type not byte sized!"); 226 227 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getPointerInfo(), 228 isVolatile, isNonTemporal, isInvariant, Alignment); 229 230 // Increment the pointer to the other half. 231 unsigned IncrementSize = NVT.getSizeInBits() / 8; 232 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr, 233 DAG.getIntPtrConstant(IncrementSize)); 234 Hi = DAG.getLoad(NVT, dl, Chain, Ptr, 235 LD->getPointerInfo().getWithOffset(IncrementSize), 236 isVolatile, isNonTemporal, isInvariant, 237 MinAlign(Alignment, IncrementSize)); 238 239 // Build a factor node to remember that this load is independent of the 240 // other one. 241 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1), 242 Hi.getValue(1)); 243 244 // Handle endianness of the load. 245 if (TLI.isBigEndian()) 246 std::swap(Lo, Hi); 247 248 // Modified the chain - switch anything that used the old chain to use 249 // the new one. 250 ReplaceValueWith(SDValue(N, 1), Chain); 251} 252 253void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) { 254 EVT OVT = N->getValueType(0); 255 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), OVT); 256 SDValue Chain = N->getOperand(0); 257 SDValue Ptr = N->getOperand(1); 258 DebugLoc dl = N->getDebugLoc(); 259 const unsigned Align = N->getConstantOperandVal(3); 260 261 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2), Align); 262 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2), 0); 263 264 // Handle endianness of the load. 265 if (TLI.isBigEndian()) 266 std::swap(Lo, Hi); 267 268 // Modified the chain - switch anything that used the old chain to use 269 // the new one. 270 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1)); 271} 272 273 274//===--------------------------------------------------------------------===// 275// Generic Operand Expansion. 276//===--------------------------------------------------------------------===// 277 278SDValue DAGTypeLegalizer::ExpandOp_BITCAST(SDNode *N) { 279 DebugLoc dl = N->getDebugLoc(); 280 if (N->getValueType(0).isVector()) { 281 // An illegal expanding type is being converted to a legal vector type. 282 // Make a two element vector out of the expanded parts and convert that 283 // instead, but only if the new vector type is legal (otherwise there 284 // is no point, and it might create expansion loops). For example, on 285 // x86 this turns v1i64 = BITCAST i64 into v1i64 = BITCAST v2i32. 286 EVT OVT = N->getOperand(0).getValueType(); 287 EVT NVT = EVT::getVectorVT(*DAG.getContext(), 288 TLI.getTypeToTransformTo(*DAG.getContext(), OVT), 289 2); 290 291 if (isTypeLegal(NVT)) { 292 SDValue Parts[2]; 293 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]); 294 295 if (TLI.isBigEndian()) 296 std::swap(Parts[0], Parts[1]); 297 298 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2); 299 return DAG.getNode(ISD::BITCAST, dl, N->getValueType(0), Vec); 300 } 301 } 302 303 // Otherwise, store to a temporary and load out again as the new type. 304 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0)); 305} 306 307SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) { 308 // The vector type is legal but the element type needs expansion. 309 EVT VecVT = N->getValueType(0); 310 unsigned NumElts = VecVT.getVectorNumElements(); 311 EVT OldVT = N->getOperand(0).getValueType(); 312 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT); 313 DebugLoc dl = N->getDebugLoc(); 314 315 assert(OldVT == VecVT.getVectorElementType() && 316 "BUILD_VECTOR operand type doesn't match vector element type!"); 317 318 // Build a vector of twice the length out of the expanded elements. 319 // For example <3 x i64> -> <6 x i32>. 320 std::vector<SDValue> NewElts; 321 NewElts.reserve(NumElts*2); 322 323 for (unsigned i = 0; i < NumElts; ++i) { 324 SDValue Lo, Hi; 325 GetExpandedOp(N->getOperand(i), Lo, Hi); 326 if (TLI.isBigEndian()) 327 std::swap(Lo, Hi); 328 NewElts.push_back(Lo); 329 NewElts.push_back(Hi); 330 } 331 332 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl, 333 EVT::getVectorVT(*DAG.getContext(), 334 NewVT, NewElts.size()), 335 &NewElts[0], NewElts.size()); 336 337 // Convert the new vector to the old vector type. 338 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec); 339} 340 341SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) { 342 SDValue Lo, Hi; 343 GetExpandedOp(N->getOperand(0), Lo, Hi); 344 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo; 345} 346 347SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) { 348 // The vector type is legal but the element type needs expansion. 349 EVT VecVT = N->getValueType(0); 350 unsigned NumElts = VecVT.getVectorNumElements(); 351 DebugLoc dl = N->getDebugLoc(); 352 353 SDValue Val = N->getOperand(1); 354 EVT OldEVT = Val.getValueType(); 355 EVT NewEVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldEVT); 356 357 assert(OldEVT == VecVT.getVectorElementType() && 358 "Inserted element type doesn't match vector element type!"); 359 360 // Bitconvert to a vector of twice the length with elements of the expanded 361 // type, insert the expanded vector elements, and then convert back. 362 EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewEVT, NumElts*2); 363 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl, 364 NewVecVT, N->getOperand(0)); 365 366 SDValue Lo, Hi; 367 GetExpandedOp(Val, Lo, Hi); 368 if (TLI.isBigEndian()) 369 std::swap(Lo, Hi); 370 371 SDValue Idx = N->getOperand(2); 372 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx); 373 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx); 374 Idx = DAG.getNode(ISD::ADD, dl, 375 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1)); 376 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx); 377 378 // Convert the new vector to the old vector type. 379 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec); 380} 381 382SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) { 383 DebugLoc dl = N->getDebugLoc(); 384 EVT VT = N->getValueType(0); 385 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() && 386 "SCALAR_TO_VECTOR operand type doesn't match vector element type!"); 387 unsigned NumElts = VT.getVectorNumElements(); 388 SmallVector<SDValue, 16> Ops(NumElts); 389 Ops[0] = N->getOperand(0); 390 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType()); 391 for (unsigned i = 1; i < NumElts; ++i) 392 Ops[i] = UndefVal; 393 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts); 394} 395 396SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) { 397 assert(ISD::isNormalStore(N) && "This routine only for normal stores!"); 398 assert(OpNo == 1 && "Can only expand the stored value so far"); 399 DebugLoc dl = N->getDebugLoc(); 400 401 StoreSDNode *St = cast<StoreSDNode>(N); 402 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), 403 St->getValue().getValueType()); 404 SDValue Chain = St->getChain(); 405 SDValue Ptr = St->getBasePtr(); 406 unsigned Alignment = St->getAlignment(); 407 bool isVolatile = St->isVolatile(); 408 bool isNonTemporal = St->isNonTemporal(); 409 410 assert(NVT.isByteSized() && "Expanded type not byte sized!"); 411 unsigned IncrementSize = NVT.getSizeInBits() / 8; 412 413 SDValue Lo, Hi; 414 GetExpandedOp(St->getValue(), Lo, Hi); 415 416 if (TLI.isBigEndian()) 417 std::swap(Lo, Hi); 418 419 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getPointerInfo(), 420 isVolatile, isNonTemporal, Alignment); 421 422 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr, 423 DAG.getIntPtrConstant(IncrementSize)); 424 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!"); 425 Hi = DAG.getStore(Chain, dl, Hi, Ptr, 426 St->getPointerInfo().getWithOffset(IncrementSize), 427 isVolatile, isNonTemporal, 428 MinAlign(Alignment, IncrementSize)); 429 430 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi); 431} 432 433 434//===--------------------------------------------------------------------===// 435// Generic Result Splitting. 436//===--------------------------------------------------------------------===// 437 438// Be careful to make no assumptions about which of Lo/Hi is stored first in 439// memory (for vectors it is always Lo first followed by Hi in the following 440// bytes; for integers and floats it is Lo first if and only if the machine is 441// little-endian). 442 443void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N, unsigned ResNo, 444 SDValue &Lo, SDValue &Hi) { 445 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo); 446 GetSplitOp(Op, Lo, Hi); 447} 448 449void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo, 450 SDValue &Hi) { 451 SDValue LL, LH, RL, RH, CL, CH; 452 DebugLoc dl = N->getDebugLoc(); 453 GetSplitOp(N->getOperand(1), LL, LH); 454 GetSplitOp(N->getOperand(2), RL, RH); 455 456 SDValue Cond = N->getOperand(0); 457 CL = CH = Cond; 458 if (Cond.getValueType().isVector()) { 459 assert(Cond.getValueType().getVectorElementType() == MVT::i1 && 460 "Condition legalized before result?"); 461 unsigned NumElements = Cond.getValueType().getVectorNumElements(); 462 EVT VCondTy = EVT::getVectorVT(*DAG.getContext(), MVT::i1, NumElements / 2); 463 CL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond, 464 DAG.getIntPtrConstant(0)); 465 CH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond, 466 DAG.getIntPtrConstant(NumElements / 2)); 467 } 468 469 Lo = DAG.getNode(N->getOpcode(), dl, LL.getValueType(), CL, LL, RL); 470 Hi = DAG.getNode(N->getOpcode(), dl, LH.getValueType(), CH, LH, RH); 471} 472 473void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo, 474 SDValue &Hi) { 475 SDValue LL, LH, RL, RH; 476 DebugLoc dl = N->getDebugLoc(); 477 GetSplitOp(N->getOperand(2), LL, LH); 478 GetSplitOp(N->getOperand(3), RL, RH); 479 480 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0), 481 N->getOperand(1), LL, RL, N->getOperand(4)); 482 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0), 483 N->getOperand(1), LH, RH, N->getOperand(4)); 484} 485 486void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) { 487 EVT LoVT, HiVT; 488 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT); 489 Lo = DAG.getUNDEF(LoVT); 490 Hi = DAG.getUNDEF(HiVT); 491} 492