1 //===-------- LegalizeTypesGeneric.cpp - Generic type legalization --------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
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.
20 //===----------------------------------------------------------------------===//
22 #include "LegalizeTypes.h"
23 #include "llvm/IR/DataLayout.h"
26 #define DEBUG_TYPE "legalize-types"
28 //===----------------------------------------------------------------------===//
29 // Generic Result Expansion.
30 //===----------------------------------------------------------------------===//
32 // These routines assume that the Lo/Hi part is stored first in memory on
33 // little/big-endian machines, followed by the Hi/Lo part. This means that
34 // they cannot be used as is on vectors, for which Lo is always stored first.
35 void DAGTypeLegalizer::ExpandRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
36 SDValue &Lo, SDValue &Hi) {
37 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
38 GetExpandedOp(Op, Lo, Hi);
41 void DAGTypeLegalizer::ExpandRes_BITCAST(SDNode *N, SDValue &Lo, SDValue &Hi) {
42 EVT OutVT = N->getValueType(0);
43 EVT NOutVT = TLI.getTypeToTransformTo(*DAG.getContext(), OutVT);
44 SDValue InOp = N->getOperand(0);
45 EVT InVT = InOp.getValueType();
48 // Handle some special cases efficiently.
49 switch (getTypeAction(InVT)) {
50 case TargetLowering::TypeLegal:
51 case TargetLowering::TypePromoteInteger:
53 case TargetLowering::TypeSoftenFloat:
54 // Convert the integer operand instead.
55 SplitInteger(GetSoftenedFloat(InOp), Lo, Hi);
56 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
57 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
59 case TargetLowering::TypeExpandInteger:
60 case TargetLowering::TypeExpandFloat:
61 // Convert the expanded pieces of the input.
62 GetExpandedOp(InOp, Lo, Hi);
63 if (TLI.hasBigEndianPartOrdering(InVT) !=
64 TLI.hasBigEndianPartOrdering(OutVT))
66 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
67 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
69 case TargetLowering::TypeSplitVector:
70 GetSplitVector(InOp, Lo, Hi);
71 if (TLI.hasBigEndianPartOrdering(OutVT))
73 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
74 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
76 case TargetLowering::TypeScalarizeVector:
77 // Convert the element instead.
78 SplitInteger(BitConvertToInteger(GetScalarizedVector(InOp)), Lo, Hi);
79 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
80 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
82 case TargetLowering::TypeWidenVector: {
83 assert(!(InVT.getVectorNumElements() & 1) && "Unsupported BITCAST");
84 InOp = GetWidenedVector(InOp);
86 std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(InVT);
87 std::tie(Lo, Hi) = DAG.SplitVector(InOp, dl, LoVT, HiVT);
88 if (TLI.hasBigEndianPartOrdering(OutVT))
90 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
91 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
96 if (InVT.isVector() && OutVT.isInteger()) {
97 // Handle cases like i64 = BITCAST v1i64 on x86, where the operand
98 // is legal but the result is not.
99 unsigned NumElems = 2;
101 EVT NVT = EVT::getVectorVT(*DAG.getContext(), ElemVT, NumElems);
103 // If <ElemVT * N> is not a legal type, try <ElemVT/2 * (N*2)>.
104 while (!isTypeLegal(NVT)) {
105 unsigned NewSizeInBits = ElemVT.getSizeInBits() / 2;
106 // If the element size is smaller than byte, bail.
107 if (NewSizeInBits < 8)
110 ElemVT = EVT::getIntegerVT(*DAG.getContext(), NewSizeInBits);
111 NVT = EVT::getVectorVT(*DAG.getContext(), ElemVT, NumElems);
114 if (isTypeLegal(NVT)) {
115 SDValue CastInOp = DAG.getNode(ISD::BITCAST, dl, NVT, InOp);
117 SmallVector<SDValue, 8> Vals;
118 for (unsigned i = 0; i < NumElems; ++i)
119 Vals.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, ElemVT,
120 CastInOp, DAG.getConstant(i,
121 TLI.getVectorIdxTy())));
123 // Build Lo, Hi pair by pairing extracted elements if needed.
125 for (unsigned e = Vals.size(); e - Slot > 2; Slot += 2, e += 1) {
126 // Each iteration will BUILD_PAIR two nodes and append the result until
127 // there are only two nodes left, i.e. Lo and Hi.
128 SDValue LHS = Vals[Slot];
129 SDValue RHS = Vals[Slot + 1];
131 if (TLI.isBigEndian())
134 Vals.push_back(DAG.getNode(ISD::BUILD_PAIR, dl,
137 LHS.getValueType().getSizeInBits() << 1),
143 if (TLI.isBigEndian())
150 // Lower the bit-convert to a store/load from the stack.
151 assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
153 // Create the stack frame object. Make sure it is aligned for both
154 // the source and expanded destination types.
156 TLI.getDataLayout()->getPrefTypeAlignment(NOutVT.
157 getTypeForEVT(*DAG.getContext()));
158 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment);
159 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
160 MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI);
162 // Emit a store to the stack slot.
163 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, PtrInfo,
166 // Load the first half from the stack slot.
167 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, PtrInfo,
168 false, false, false, 0);
170 // Increment the pointer to the other half.
171 unsigned IncrementSize = NOutVT.getSizeInBits() / 8;
172 StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
173 DAG.getConstant(IncrementSize,
174 StackPtr.getValueType()));
176 // Load the second half from the stack slot.
177 Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr,
178 PtrInfo.getWithOffset(IncrementSize), false,
179 false, false, MinAlign(Alignment, IncrementSize));
181 // Handle endianness of the load.
182 if (TLI.hasBigEndianPartOrdering(OutVT))
186 void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
188 // Return the operands.
189 Lo = N->getOperand(0);
190 Hi = N->getOperand(1);
193 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
195 GetExpandedOp(N->getOperand(0), Lo, Hi);
196 SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ?
199 assert(Part.getValueType() == N->getValueType(0) &&
200 "Type twice as big as expanded type not itself expanded!");
202 GetPairElements(Part, Lo, Hi);
205 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
207 SDValue OldVec = N->getOperand(0);
208 unsigned OldElts = OldVec.getValueType().getVectorNumElements();
209 EVT OldEltVT = OldVec.getValueType().getVectorElementType();
212 // Convert to a vector of the expanded element type, for example
213 // <3 x i64> -> <6 x i32>.
214 EVT OldVT = N->getValueType(0);
215 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
217 if (OldVT != OldEltVT) {
218 // The result of EXTRACT_VECTOR_ELT may be larger than the element type of
219 // the input vector. If so, extend the elements of the input vector to the
220 // same bitwidth as the result before expanding.
221 assert(OldEltVT.bitsLT(OldVT) && "Result type smaller then element type!");
222 EVT NVecVT = EVT::getVectorVT(*DAG.getContext(), OldVT, OldElts);
223 OldVec = DAG.getNode(ISD::ANY_EXTEND, dl, NVecVT, N->getOperand(0));
226 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
227 EVT::getVectorVT(*DAG.getContext(),
231 // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector.
232 SDValue Idx = N->getOperand(1);
234 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
235 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
237 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
238 DAG.getConstant(1, Idx.getValueType()));
239 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
241 if (TLI.isBigEndian())
245 void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo,
247 assert(ISD::isNormalLoad(N) && "This routine only for normal loads!");
250 LoadSDNode *LD = cast<LoadSDNode>(N);
251 EVT ValueVT = LD->getValueType(0);
252 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), ValueVT);
253 SDValue Chain = LD->getChain();
254 SDValue Ptr = LD->getBasePtr();
255 unsigned Alignment = LD->getAlignment();
256 bool isVolatile = LD->isVolatile();
257 bool isNonTemporal = LD->isNonTemporal();
258 bool isInvariant = LD->isInvariant();
259 AAMDNodes AAInfo = LD->getAAInfo();
261 assert(NVT.isByteSized() && "Expanded type not byte sized!");
263 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getPointerInfo(),
264 isVolatile, isNonTemporal, isInvariant, Alignment,
267 // Increment the pointer to the other half.
268 unsigned IncrementSize = NVT.getSizeInBits() / 8;
269 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
270 DAG.getConstant(IncrementSize, Ptr.getValueType()));
271 Hi = DAG.getLoad(NVT, dl, Chain, Ptr,
272 LD->getPointerInfo().getWithOffset(IncrementSize),
273 isVolatile, isNonTemporal, isInvariant,
274 MinAlign(Alignment, IncrementSize), AAInfo);
276 // Build a factor node to remember that this load is independent of the
278 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
281 // Handle endianness of the load.
282 if (TLI.hasBigEndianPartOrdering(ValueVT))
285 // Modified the chain - switch anything that used the old chain to use
287 ReplaceValueWith(SDValue(N, 1), Chain);
290 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
291 EVT OVT = N->getValueType(0);
292 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), OVT);
293 SDValue Chain = N->getOperand(0);
294 SDValue Ptr = N->getOperand(1);
296 const unsigned Align = N->getConstantOperandVal(3);
298 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2), Align);
299 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2), 0);
301 // Handle endianness of the load.
302 if (TLI.hasBigEndianPartOrdering(OVT))
305 // Modified the chain - switch anything that used the old chain to use
307 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
311 //===--------------------------------------------------------------------===//
312 // Generic Operand Expansion.
313 //===--------------------------------------------------------------------===//
315 void DAGTypeLegalizer::IntegerToVector(SDValue Op, unsigned NumElements,
316 SmallVectorImpl<SDValue> &Ops,
318 assert(Op.getValueType().isInteger());
322 if (NumElements > 1) {
324 SplitInteger(Op, Parts[0], Parts[1]);
325 if (TLI.isBigEndian())
326 std::swap(Parts[0], Parts[1]);
327 IntegerToVector(Parts[0], NumElements, Ops, EltVT);
328 IntegerToVector(Parts[1], NumElements, Ops, EltVT);
330 Ops.push_back(DAG.getNode(ISD::BITCAST, DL, EltVT, Op));
334 SDValue DAGTypeLegalizer::ExpandOp_BITCAST(SDNode *N) {
336 if (N->getValueType(0).isVector()) {
337 // An illegal expanding type is being converted to a legal vector type.
338 // Make a two element vector out of the expanded parts and convert that
339 // instead, but only if the new vector type is legal (otherwise there
340 // is no point, and it might create expansion loops). For example, on
341 // x86 this turns v1i64 = BITCAST i64 into v1i64 = BITCAST v2i32.
343 // FIXME: I'm not sure why we are first trying to split the input into
344 // a 2 element vector, so I'm leaving it here to maintain the current
346 unsigned NumElts = 2;
347 EVT OVT = N->getOperand(0).getValueType();
348 EVT NVT = EVT::getVectorVT(*DAG.getContext(),
349 TLI.getTypeToTransformTo(*DAG.getContext(), OVT),
351 if (!isTypeLegal(NVT)) {
352 // If we can't find a legal type by splitting the integer in half,
353 // then we can use the node's value type.
354 NumElts = N->getValueType(0).getVectorNumElements();
355 NVT = N->getValueType(0);
358 SmallVector<SDValue, 8> Ops;
359 IntegerToVector(N->getOperand(0), NumElts, Ops, NVT.getVectorElementType());
361 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT,
362 makeArrayRef(Ops.data(), NumElts));
363 return DAG.getNode(ISD::BITCAST, dl, N->getValueType(0), Vec);
366 // Otherwise, store to a temporary and load out again as the new type.
367 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
370 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
371 // The vector type is legal but the element type needs expansion.
372 EVT VecVT = N->getValueType(0);
373 unsigned NumElts = VecVT.getVectorNumElements();
374 EVT OldVT = N->getOperand(0).getValueType();
375 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
378 assert(OldVT == VecVT.getVectorElementType() &&
379 "BUILD_VECTOR operand type doesn't match vector element type!");
381 // Build a vector of twice the length out of the expanded elements.
382 // For example <3 x i64> -> <6 x i32>.
383 std::vector<SDValue> NewElts;
384 NewElts.reserve(NumElts*2);
386 for (unsigned i = 0; i < NumElts; ++i) {
388 GetExpandedOp(N->getOperand(i), Lo, Hi);
389 if (TLI.isBigEndian())
391 NewElts.push_back(Lo);
392 NewElts.push_back(Hi);
395 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
396 EVT::getVectorVT(*DAG.getContext(),
397 NewVT, NewElts.size()),
400 // Convert the new vector to the old vector type.
401 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
404 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
406 GetExpandedOp(N->getOperand(0), Lo, Hi);
407 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
410 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
411 // The vector type is legal but the element type needs expansion.
412 EVT VecVT = N->getValueType(0);
413 unsigned NumElts = VecVT.getVectorNumElements();
416 SDValue Val = N->getOperand(1);
417 EVT OldEVT = Val.getValueType();
418 EVT NewEVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldEVT);
420 assert(OldEVT == VecVT.getVectorElementType() &&
421 "Inserted element type doesn't match vector element type!");
423 // Bitconvert to a vector of twice the length with elements of the expanded
424 // type, insert the expanded vector elements, and then convert back.
425 EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewEVT, NumElts*2);
426 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
427 NewVecVT, N->getOperand(0));
430 GetExpandedOp(Val, Lo, Hi);
431 if (TLI.isBigEndian())
434 SDValue Idx = N->getOperand(2);
435 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
436 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
437 Idx = DAG.getNode(ISD::ADD, dl,
438 Idx.getValueType(), Idx,
439 DAG.getConstant(1, Idx.getValueType()));
440 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
442 // Convert the new vector to the old vector type.
443 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
446 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
448 EVT VT = N->getValueType(0);
449 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
450 "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
451 unsigned NumElts = VT.getVectorNumElements();
452 SmallVector<SDValue, 16> Ops(NumElts);
453 Ops[0] = N->getOperand(0);
454 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
455 for (unsigned i = 1; i < NumElts; ++i)
457 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, Ops);
460 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
461 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
462 assert(OpNo == 1 && "Can only expand the stored value so far");
465 StoreSDNode *St = cast<StoreSDNode>(N);
466 EVT ValueVT = St->getValue().getValueType();
467 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), ValueVT);
468 SDValue Chain = St->getChain();
469 SDValue Ptr = St->getBasePtr();
470 unsigned Alignment = St->getAlignment();
471 bool isVolatile = St->isVolatile();
472 bool isNonTemporal = St->isNonTemporal();
473 AAMDNodes AAInfo = St->getAAInfo();
475 assert(NVT.isByteSized() && "Expanded type not byte sized!");
476 unsigned IncrementSize = NVT.getSizeInBits() / 8;
479 GetExpandedOp(St->getValue(), Lo, Hi);
481 if (TLI.hasBigEndianPartOrdering(ValueVT))
484 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getPointerInfo(),
485 isVolatile, isNonTemporal, Alignment, AAInfo);
487 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
488 DAG.getConstant(IncrementSize, Ptr.getValueType()));
489 Hi = DAG.getStore(Chain, dl, Hi, Ptr,
490 St->getPointerInfo().getWithOffset(IncrementSize),
491 isVolatile, isNonTemporal,
492 MinAlign(Alignment, IncrementSize), AAInfo);
494 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
498 //===--------------------------------------------------------------------===//
499 // Generic Result Splitting.
500 //===--------------------------------------------------------------------===//
502 // Be careful to make no assumptions about which of Lo/Hi is stored first in
503 // memory (for vectors it is always Lo first followed by Hi in the following
504 // bytes; for integers and floats it is Lo first if and only if the machine is
507 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
508 SDValue &Lo, SDValue &Hi) {
509 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
510 GetSplitOp(Op, Lo, Hi);
513 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
515 SDValue LL, LH, RL, RH, CL, CH;
517 GetSplitOp(N->getOperand(1), LL, LH);
518 GetSplitOp(N->getOperand(2), RL, RH);
520 SDValue Cond = N->getOperand(0);
522 if (Cond.getValueType().isVector()) {
523 // Check if there are already splitted versions of the vector available and
524 // use those instead of splitting the mask operand again.
525 if (getTypeAction(Cond.getValueType()) == TargetLowering::TypeSplitVector)
526 GetSplitVector(Cond, CL, CH);
528 std::tie(CL, CH) = DAG.SplitVector(Cond, dl);
531 Lo = DAG.getNode(N->getOpcode(), dl, LL.getValueType(), CL, LL, RL);
532 Hi = DAG.getNode(N->getOpcode(), dl, LH.getValueType(), CH, LH, RH);
535 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
537 SDValue LL, LH, RL, RH;
539 GetSplitOp(N->getOperand(2), LL, LH);
540 GetSplitOp(N->getOperand(3), RL, RH);
542 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
543 N->getOperand(1), LL, RL, N->getOperand(4));
544 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
545 N->getOperand(1), LH, RH, N->getOperand(4));
548 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
550 std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(N->getValueType(0));
551 Lo = DAG.getUNDEF(LoVT);
552 Hi = DAG.getUNDEF(HiVT);