xref: /freebsd/contrib/llvm-project/llvm/lib/CodeGen/SelectionDAG/LegalizeTypesGeneric.cpp (revision 700637cbb5e582861067a11aaca4d053546871d2)
1 //===-------- LegalizeTypesGeneric.cpp - Generic type legalization --------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements generic type expansion and splitting for LegalizeTypes.
10 // The routines here perform legalization when the details of the type (such as
11 // whether it is an integer or a float) do not matter.
12 // Expansion is the act of changing a computation in an illegal type to be a
13 // computation in two identical registers of a smaller type.  The Lo/Hi part
14 // is required to be stored first in memory on little/big-endian machines.
15 // Splitting is the act of changing a computation in an illegal type to be a
16 // computation in two not necessarily identical registers of a smaller type.
17 // There are no requirements on how the type is represented in memory.
18 //
19 //===----------------------------------------------------------------------===//
20 
21 #include "LegalizeTypes.h"
22 #include "llvm/IR/DataLayout.h"
23 using namespace llvm;
24 
25 #define DEBUG_TYPE "legalize-types"
26 
27 //===----------------------------------------------------------------------===//
28 // Generic Result Expansion.
29 //===----------------------------------------------------------------------===//
30 
31 // These routines assume that the Lo/Hi part is stored first in memory on
32 // little/big-endian machines, followed by the Hi/Lo part.  This means that
33 // they cannot be used as is on vectors, for which Lo is always stored first.
ExpandRes_MERGE_VALUES(SDNode * N,unsigned ResNo,SDValue & Lo,SDValue & Hi)34 void DAGTypeLegalizer::ExpandRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
35                                               SDValue &Lo, SDValue &Hi) {
36   SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
37   GetExpandedOp(Op, Lo, Hi);
38 }
39 
ExpandRes_BITCAST(SDNode * N,SDValue & Lo,SDValue & Hi)40 void DAGTypeLegalizer::ExpandRes_BITCAST(SDNode *N, SDValue &Lo, SDValue &Hi) {
41   EVT OutVT = N->getValueType(0);
42   EVT NOutVT = TLI.getTypeToTransformTo(*DAG.getContext(), OutVT);
43   SDValue InOp = N->getOperand(0);
44   EVT InVT = InOp.getValueType();
45   SDLoc dl(N);
46 
47   // Handle some special cases efficiently.
48   switch (getTypeAction(InVT)) {
49     case TargetLowering::TypeLegal:
50     case TargetLowering::TypePromoteInteger:
51       break;
52     case TargetLowering::TypePromoteFloat:
53     case TargetLowering::TypeSoftPromoteHalf:
54       llvm_unreachable("Bitcast of a promotion-needing float should never need"
55                        "expansion");
56     case TargetLowering::TypeSoftenFloat:
57       SplitInteger(GetSoftenedFloat(InOp), Lo, Hi);
58       Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
59       Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
60       return;
61     case TargetLowering::TypeExpandInteger:
62     case TargetLowering::TypeExpandFloat: {
63       auto &DL = DAG.getDataLayout();
64       // Convert the expanded pieces of the input.
65       GetExpandedOp(InOp, Lo, Hi);
66       if (TLI.hasBigEndianPartOrdering(InVT, DL) !=
67           TLI.hasBigEndianPartOrdering(OutVT, DL))
68         std::swap(Lo, Hi);
69       Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
70       Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
71       return;
72     }
73     case TargetLowering::TypeSplitVector:
74       GetSplitVector(InOp, Lo, Hi);
75       if (TLI.hasBigEndianPartOrdering(OutVT, DAG.getDataLayout()))
76         std::swap(Lo, Hi);
77       Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
78       Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
79       return;
80     case TargetLowering::TypeScalarizeVector:
81       // Convert the element instead.
82       SplitInteger(BitConvertToInteger(GetScalarizedVector(InOp)), Lo, Hi);
83       Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
84       Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
85       return;
86     case TargetLowering::TypeScalarizeScalableVector:
87       report_fatal_error("Scalarization of scalable vectors is not supported.");
88     case TargetLowering::TypeWidenVector: {
89       assert(!(InVT.getVectorNumElements() & 1) && "Unsupported BITCAST");
90       InOp = GetWidenedVector(InOp);
91       EVT LoVT, HiVT;
92       std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(InVT);
93       std::tie(Lo, Hi) = DAG.SplitVector(InOp, dl, LoVT, HiVT);
94       if (TLI.hasBigEndianPartOrdering(OutVT, DAG.getDataLayout()))
95         std::swap(Lo, Hi);
96       Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
97       Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
98       return;
99     }
100   }
101 
102   if (InVT.isVector() && OutVT.isInteger()) {
103     // Handle cases like i64 = BITCAST v1i64 on x86, where the operand
104     // is legal but the result is not.
105     unsigned NumElems = 2;
106     EVT ElemVT = NOutVT;
107     EVT NVT = EVT::getVectorVT(*DAG.getContext(), ElemVT, NumElems);
108 
109     // If <ElemVT * N> is not a legal type, try <ElemVT/2 * (N*2)>.
110     while (!isTypeLegal(NVT)) {
111       unsigned NewSizeInBits = ElemVT.getSizeInBits() / 2;
112       // If the element size is smaller than byte, bail.
113       if (NewSizeInBits < 8)
114         break;
115       NumElems *= 2;
116       ElemVT = EVT::getIntegerVT(*DAG.getContext(), NewSizeInBits);
117       NVT = EVT::getVectorVT(*DAG.getContext(), ElemVT, NumElems);
118     }
119 
120     if (isTypeLegal(NVT)) {
121       SDValue CastInOp = DAG.getNode(ISD::BITCAST, dl, NVT, InOp);
122 
123       SmallVector<SDValue, 8> Vals;
124       for (unsigned i = 0; i < NumElems; ++i)
125         Vals.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, ElemVT,
126                                    CastInOp, DAG.getVectorIdxConstant(i, dl)));
127 
128       // Build Lo, Hi pair by pairing extracted elements if needed.
129       unsigned Slot = 0;
130       for (unsigned e = Vals.size(); e - Slot > 2; Slot += 2, e += 1) {
131         // Each iteration will BUILD_PAIR two nodes and append the result until
132         // there are only two nodes left, i.e. Lo and Hi.
133         SDValue LHS = Vals[Slot];
134         SDValue RHS = Vals[Slot + 1];
135 
136         if (DAG.getDataLayout().isBigEndian())
137           std::swap(LHS, RHS);
138 
139         Vals.push_back(DAG.getNode(
140             ISD::BUILD_PAIR, dl,
141             EVT::getIntegerVT(*DAG.getContext(), LHS.getValueSizeInBits() << 1),
142             LHS, RHS));
143       }
144       Lo = Vals[Slot++];
145       Hi = Vals[Slot++];
146 
147       if (DAG.getDataLayout().isBigEndian())
148         std::swap(Lo, Hi);
149 
150       return;
151     }
152   }
153 
154   // Lower the bit-convert to a store/load from the stack.
155   assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
156 
157   // Create the stack frame object.  Make sure it is aligned for both
158   // the source and expanded destination types.
159 
160   // In cases where the vector is illegal it will be broken down into parts
161   // and stored in parts - we should use the alignment for the smallest part.
162   Align InAlign = DAG.getReducedAlign(InVT, /*UseABI=*/false);
163   Align NOutAlign = DAG.getReducedAlign(NOutVT, /*UseABI=*/false);
164   Align Align = std::max(InAlign, NOutAlign);
165   SDValue StackPtr = DAG.CreateStackTemporary(InVT.getStoreSize(), Align);
166   int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
167   MachinePointerInfo PtrInfo =
168       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI);
169 
170   // Emit a store to the stack slot.
171   SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, PtrInfo);
172 
173   // Load the first half from the stack slot.
174   Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, PtrInfo, NOutAlign);
175 
176   // Increment the pointer to the other half.
177   unsigned IncrementSize = NOutVT.getSizeInBits() / 8;
178   StackPtr =
179       DAG.getMemBasePlusOffset(StackPtr, TypeSize::getFixed(IncrementSize), dl);
180 
181   // Load the second half from the stack slot.
182   Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr,
183                    PtrInfo.getWithOffset(IncrementSize), NOutAlign);
184 
185   // Handle endianness of the load.
186   if (TLI.hasBigEndianPartOrdering(OutVT, DAG.getDataLayout()))
187     std::swap(Lo, Hi);
188 }
189 
ExpandRes_BUILD_PAIR(SDNode * N,SDValue & Lo,SDValue & Hi)190 void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
191                                             SDValue &Hi) {
192   // Return the operands.
193   Lo = N->getOperand(0);
194   Hi = N->getOperand(1);
195 }
196 
ExpandRes_EXTRACT_ELEMENT(SDNode * N,SDValue & Lo,SDValue & Hi)197 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
198                                                  SDValue &Hi) {
199   GetExpandedOp(N->getOperand(0), Lo, Hi);
200   SDValue Part = N->getConstantOperandVal(1) ? Hi : Lo;
201 
202   assert(Part.getValueType() == N->getValueType(0) &&
203          "Type twice as big as expanded type not itself expanded!");
204 
205   GetPairElements(Part, Lo, Hi);
206 }
207 
ExpandRes_EXTRACT_VECTOR_ELT(SDNode * N,SDValue & Lo,SDValue & Hi)208 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
209                                                     SDValue &Hi) {
210   SDValue OldVec = N->getOperand(0);
211   ElementCount OldEltCount = OldVec.getValueType().getVectorElementCount();
212   EVT OldEltVT = OldVec.getValueType().getVectorElementType();
213   SDLoc dl(N);
214 
215   // Convert to a vector of the expanded element type, for example
216   // <3 x i64> -> <6 x i32>.
217   EVT OldVT = N->getValueType(0);
218   EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
219 
220   if (OldVT != OldEltVT) {
221     // The result of EXTRACT_VECTOR_ELT may be larger than the element type of
222     // the input vector.  If so, extend the elements of the input vector to the
223     // same bitwidth as the result before expanding.
224     assert(OldEltVT.bitsLT(OldVT) && "Result type smaller then element type!");
225     EVT NVecVT = EVT::getVectorVT(*DAG.getContext(), OldVT, OldEltCount);
226     OldVec = DAG.getNode(ISD::ANY_EXTEND, dl, NVecVT, N->getOperand(0));
227   }
228 
229   SDValue NewVec = DAG.getNode(
230       ISD::BITCAST, dl,
231       EVT::getVectorVT(*DAG.getContext(), NewVT, OldEltCount * 2), OldVec);
232 
233   // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector.
234   SDValue Idx = N->getOperand(1);
235 
236   Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
237   Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
238 
239   Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
240                     DAG.getConstant(1, dl, Idx.getValueType()));
241   Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
242 
243   if (DAG.getDataLayout().isBigEndian())
244     std::swap(Lo, Hi);
245 }
246 
ExpandRes_NormalLoad(SDNode * N,SDValue & Lo,SDValue & Hi)247 void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo,
248                                             SDValue &Hi) {
249   assert(ISD::isNormalLoad(N) && "This routine only for normal loads!");
250   SDLoc dl(N);
251 
252   LoadSDNode *LD = cast<LoadSDNode>(N);
253   assert(!LD->isAtomic() && "Atomics can not be split");
254   EVT ValueVT = LD->getValueType(0);
255   EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), ValueVT);
256   SDValue Chain = LD->getChain();
257   SDValue Ptr = LD->getBasePtr();
258   AAMDNodes AAInfo = LD->getAAInfo();
259 
260   assert(NVT.isByteSized() && "Expanded type not byte sized!");
261 
262   Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getPointerInfo(),
263                    LD->getBaseAlign(), LD->getMemOperand()->getFlags(), AAInfo);
264 
265   // Increment the pointer to the other half.
266   unsigned IncrementSize = NVT.getSizeInBits() / 8;
267   Ptr = DAG.getObjectPtrOffset(dl, Ptr, TypeSize::getFixed(IncrementSize));
268   Hi = DAG.getLoad(NVT, dl, Chain, Ptr,
269                    LD->getPointerInfo().getWithOffset(IncrementSize),
270                    LD->getBaseAlign(), LD->getMemOperand()->getFlags(), AAInfo);
271 
272   // Build a factor node to remember that this load is independent of the
273   // other one.
274   Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
275                       Hi.getValue(1));
276 
277   // Handle endianness of the load.
278   if (TLI.hasBigEndianPartOrdering(ValueVT, DAG.getDataLayout()))
279     std::swap(Lo, Hi);
280 
281   // Modified the chain - switch anything that used the old chain to use
282   // the new one.
283   ReplaceValueWith(SDValue(N, 1), Chain);
284 }
285 
ExpandRes_VAARG(SDNode * N,SDValue & Lo,SDValue & Hi)286 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
287   EVT OVT = N->getValueType(0);
288   EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), OVT);
289   SDValue Chain = N->getOperand(0);
290   SDValue Ptr = N->getOperand(1);
291   SDLoc dl(N);
292   const unsigned Align = N->getConstantOperandVal(3);
293 
294   Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2), Align);
295   Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2), 0);
296   Chain = Hi.getValue(1);
297 
298   // Handle endianness of the load.
299   if (TLI.hasBigEndianPartOrdering(OVT, DAG.getDataLayout()))
300     std::swap(Lo, Hi);
301 
302   // Modified the chain - switch anything that used the old chain to use
303   // the new one.
304   ReplaceValueWith(SDValue(N, 1), Chain);
305 }
306 
307 
308 //===--------------------------------------------------------------------===//
309 // Generic Operand Expansion.
310 //===--------------------------------------------------------------------===//
311 
IntegerToVector(SDValue Op,unsigned NumElements,SmallVectorImpl<SDValue> & Ops,EVT EltVT)312 void DAGTypeLegalizer::IntegerToVector(SDValue Op, unsigned NumElements,
313                                        SmallVectorImpl<SDValue> &Ops,
314                                        EVT EltVT) {
315   assert(Op.getValueType().isInteger());
316   SDLoc DL(Op);
317   SDValue Parts[2];
318 
319   if (NumElements > 1) {
320     NumElements >>= 1;
321     SplitInteger(Op, Parts[0], Parts[1]);
322     if (DAG.getDataLayout().isBigEndian())
323       std::swap(Parts[0], Parts[1]);
324     IntegerToVector(Parts[0], NumElements, Ops, EltVT);
325     IntegerToVector(Parts[1], NumElements, Ops, EltVT);
326   } else {
327     Ops.push_back(DAG.getNode(ISD::BITCAST, DL, EltVT, Op));
328   }
329 }
330 
ExpandOp_BITCAST(SDNode * N)331 SDValue DAGTypeLegalizer::ExpandOp_BITCAST(SDNode *N) {
332   SDLoc dl(N);
333   if (N->getValueType(0).isVector() &&
334       N->getOperand(0).getValueType().isInteger()) {
335     // An illegal expanding type is being converted to a legal vector type.
336     // Make a two element vector out of the expanded parts and convert that
337     // instead, but only if the new vector type is legal (otherwise there
338     // is no point, and it might create expansion loops).  For example, on
339     // x86 this turns v1i64 = BITCAST i64 into v1i64 = BITCAST v2i32.
340     //
341     // FIXME: I'm not sure why we are first trying to split the input into
342     // a 2 element vector, so I'm leaving it here to maintain the current
343     // behavior.
344     unsigned NumElts = 2;
345     EVT OVT = N->getOperand(0).getValueType();
346     EVT NVT = EVT::getVectorVT(*DAG.getContext(),
347                                TLI.getTypeToTransformTo(*DAG.getContext(), OVT),
348                                NumElts);
349     if (!isTypeLegal(NVT)) {
350       // If we can't find a legal type by splitting the integer in half,
351       // then we can use the node's value type.
352       NumElts = N->getValueType(0).getVectorNumElements();
353       NVT = N->getValueType(0);
354     }
355 
356     SmallVector<SDValue, 8> Ops;
357     IntegerToVector(N->getOperand(0), NumElts, Ops, NVT.getVectorElementType());
358 
359     SDValue Vec = DAG.getBuildVector(NVT, dl, ArrayRef(Ops.data(), NumElts));
360     return DAG.getNode(ISD::BITCAST, dl, N->getValueType(0), Vec);
361   }
362 
363   // Otherwise, store to a temporary and load out again as the new type.
364   return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
365 }
366 
ExpandOp_BUILD_VECTOR(SDNode * N)367 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
368   // The vector type is legal but the element type needs expansion.
369   EVT VecVT = N->getValueType(0);
370   unsigned NumElts = VecVT.getVectorNumElements();
371   EVT OldVT = N->getOperand(0).getValueType();
372   EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
373   SDLoc dl(N);
374 
375   assert(OldVT == VecVT.getVectorElementType() &&
376          "BUILD_VECTOR operand type doesn't match vector element type!");
377 
378   if (VecVT.isInteger() && TLI.isOperationLegal(ISD::SPLAT_VECTOR, VecVT) &&
379       TLI.isOperationLegalOrCustom(ISD::SPLAT_VECTOR_PARTS, VecVT)) {
380     if (SDValue V = cast<BuildVectorSDNode>(N)->getSplatValue()) {
381       SDValue Lo, Hi;
382       GetExpandedOp(V, Lo, Hi);
383       return DAG.getNode(ISD::SPLAT_VECTOR_PARTS, dl, VecVT, Lo, Hi);
384     }
385   }
386 
387   // Build a vector of twice the length out of the expanded elements.
388   // For example <3 x i64> -> <6 x i32>.
389   SmallVector<SDValue, 16> NewElts;
390   NewElts.reserve(NumElts*2);
391 
392   for (unsigned i = 0; i < NumElts; ++i) {
393     SDValue Lo, Hi;
394     GetExpandedOp(N->getOperand(i), Lo, Hi);
395     if (DAG.getDataLayout().isBigEndian())
396       std::swap(Lo, Hi);
397     NewElts.push_back(Lo);
398     NewElts.push_back(Hi);
399   }
400 
401   EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewVT, NewElts.size());
402   SDValue NewVec = DAG.getBuildVector(NewVecVT, dl, NewElts);
403 
404   // Convert the new vector to the old vector type.
405   return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
406 }
407 
ExpandOp_EXTRACT_ELEMENT(SDNode * N)408 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
409   SDValue Lo, Hi;
410   GetExpandedOp(N->getOperand(0), Lo, Hi);
411   return N->getConstantOperandVal(1) ? Hi : Lo;
412 }
413 
414 // Split the integer operand in two and create a second FAKE_USE node for
415 // the other half. The original SDNode is updated in place.
ExpandOp_FAKE_USE(SDNode * N)416 SDValue DAGTypeLegalizer::ExpandOp_FAKE_USE(SDNode *N) {
417   SDValue Lo, Hi;
418   SDValue Chain = N->getOperand(0);
419   GetExpandedOp(N->getOperand(1), Lo, Hi);
420   SDValue LoUse = DAG.getNode(ISD::FAKE_USE, SDLoc(), MVT::Other, Chain, Lo);
421   DAG.UpdateNodeOperands(N, LoUse, Hi);
422   return SDValue(N, 0);
423 }
424 
ExpandOp_INSERT_VECTOR_ELT(SDNode * N)425 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
426   // The vector type is legal but the element type needs expansion.
427   EVT VecVT = N->getValueType(0);
428   unsigned NumElts = VecVT.getVectorNumElements();
429   SDLoc dl(N);
430 
431   SDValue Val = N->getOperand(1);
432   EVT OldEVT = Val.getValueType();
433   EVT NewEVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldEVT);
434 
435   assert(OldEVT == VecVT.getVectorElementType() &&
436          "Inserted element type doesn't match vector element type!");
437 
438   // Bitconvert to a vector of twice the length with elements of the expanded
439   // type, insert the expanded vector elements, and then convert back.
440   EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewEVT, NumElts*2);
441   SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
442                                NewVecVT, N->getOperand(0));
443 
444   SDValue Lo, Hi;
445   GetExpandedOp(Val, Lo, Hi);
446   if (DAG.getDataLayout().isBigEndian())
447     std::swap(Lo, Hi);
448 
449   SDValue Idx = N->getOperand(2);
450   Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
451   NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
452   Idx = DAG.getNode(ISD::ADD, dl,
453                     Idx.getValueType(), Idx,
454                     DAG.getConstant(1, dl, Idx.getValueType()));
455   NewVec =  DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
456 
457   // Convert the new vector to the old vector type.
458   return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
459 }
460 
ExpandOp_SCALAR_TO_VECTOR(SDNode * N)461 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
462   SDLoc dl(N);
463   EVT VT = N->getValueType(0);
464   assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
465          "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
466   unsigned NumElts = VT.getVectorNumElements();
467   SmallVector<SDValue, 16> Ops(NumElts);
468   Ops[0] = N->getOperand(0);
469   SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
470   for (unsigned i = 1; i < NumElts; ++i)
471     Ops[i] = UndefVal;
472   return DAG.getBuildVector(VT, dl, Ops);
473 }
474 
ExpandOp_NormalStore(SDNode * N,unsigned OpNo)475 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
476   assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
477   assert(OpNo == 1 && "Can only expand the stored value so far");
478   SDLoc dl(N);
479 
480   StoreSDNode *St = cast<StoreSDNode>(N);
481   assert(!St->isAtomic() && "Atomics can not be split");
482   EVT ValueVT = St->getValue().getValueType();
483   EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), ValueVT);
484   SDValue Chain = St->getChain();
485   SDValue Ptr = St->getBasePtr();
486   AAMDNodes AAInfo = St->getAAInfo();
487 
488   assert(NVT.isByteSized() && "Expanded type not byte sized!");
489   unsigned IncrementSize = NVT.getSizeInBits() / 8;
490 
491   SDValue Lo, Hi;
492   GetExpandedOp(St->getValue(), Lo, Hi);
493 
494   if (TLI.hasBigEndianPartOrdering(ValueVT, DAG.getDataLayout()))
495     std::swap(Lo, Hi);
496 
497   Lo =
498       DAG.getStore(Chain, dl, Lo, Ptr, St->getPointerInfo(), St->getBaseAlign(),
499                    St->getMemOperand()->getFlags(), AAInfo);
500 
501   Ptr = DAG.getObjectPtrOffset(dl, Ptr, TypeSize::getFixed(IncrementSize));
502   Hi = DAG.getStore(
503       Chain, dl, Hi, Ptr, St->getPointerInfo().getWithOffset(IncrementSize),
504       St->getBaseAlign(), St->getMemOperand()->getFlags(), AAInfo);
505 
506   return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
507 }
508 
509 
510 //===--------------------------------------------------------------------===//
511 // Generic Result Splitting.
512 //===--------------------------------------------------------------------===//
513 
514 // Be careful to make no assumptions about which of Lo/Hi is stored first in
515 // memory (for vectors it is always Lo first followed by Hi in the following
516 // bytes; for integers and floats it is Lo first if and only if the machine is
517 // little-endian).
518 
SplitRes_MERGE_VALUES(SDNode * N,unsigned ResNo,SDValue & Lo,SDValue & Hi)519 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
520                                              SDValue &Lo, SDValue &Hi) {
521   SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
522   GetSplitOp(Op, Lo, Hi);
523 }
524 
SplitRes_Select(SDNode * N,SDValue & Lo,SDValue & Hi)525 void DAGTypeLegalizer::SplitRes_Select(SDNode *N, SDValue &Lo, SDValue &Hi) {
526   SDValue LL, LH, RL, RH, CL, CH;
527   SDLoc dl(N);
528   unsigned Opcode = N->getOpcode();
529   GetSplitOp(N->getOperand(1), LL, LH);
530   GetSplitOp(N->getOperand(2), RL, RH);
531 
532   SDValue Cond = N->getOperand(0);
533   CL = CH = Cond;
534   if (Cond.getValueType().isVector()) {
535     if (SDValue Res = WidenVSELECTMask(N))
536       std::tie(CL, CH) = DAG.SplitVector(Res, dl);
537     // Check if there are already splitted versions of the vector available and
538     // use those instead of splitting the mask operand again.
539     else if (getTypeAction(Cond.getValueType()) ==
540              TargetLowering::TypeSplitVector)
541       GetSplitVector(Cond, CL, CH);
542     // It seems to improve code to generate two narrow SETCCs as opposed to
543     // splitting a wide result vector.
544     else if (Cond.getOpcode() == ISD::SETCC) {
545       // If the condition is a vXi1 vector, and the LHS of the setcc is a legal
546       // type and the setcc result type is the same vXi1, then leave the setcc
547       // alone.
548       EVT CondLHSVT = Cond.getOperand(0).getValueType();
549       if (Cond.getValueType().getVectorElementType() == MVT::i1 &&
550           isTypeLegal(CondLHSVT) &&
551           getSetCCResultType(CondLHSVT) == Cond.getValueType())
552         std::tie(CL, CH) = DAG.SplitVector(Cond, dl);
553       else
554         SplitVecRes_SETCC(Cond.getNode(), CL, CH);
555     } else
556       std::tie(CL, CH) = DAG.SplitVector(Cond, dl);
557   }
558 
559   if (Opcode != ISD::VP_SELECT && Opcode != ISD::VP_MERGE) {
560     Lo = DAG.getNode(Opcode, dl, LL.getValueType(), CL, LL, RL);
561     Hi = DAG.getNode(Opcode, dl, LH.getValueType(), CH, LH, RH);
562     return;
563   }
564 
565   SDValue EVLLo, EVLHi;
566   std::tie(EVLLo, EVLHi) =
567       DAG.SplitEVL(N->getOperand(3), N->getValueType(0), dl);
568 
569   Lo = DAG.getNode(Opcode, dl, LL.getValueType(), CL, LL, RL, EVLLo);
570   Hi = DAG.getNode(Opcode, dl, LH.getValueType(), CH, LH, RH, EVLHi);
571 }
572 
SplitRes_SELECT_CC(SDNode * N,SDValue & Lo,SDValue & Hi)573 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
574                                           SDValue &Hi) {
575   SDValue LL, LH, RL, RH;
576   SDLoc dl(N);
577   GetSplitOp(N->getOperand(2), LL, LH);
578   GetSplitOp(N->getOperand(3), RL, RH);
579 
580   Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
581                    N->getOperand(1), LL, RL, N->getOperand(4));
582   Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
583                    N->getOperand(1), LH, RH, N->getOperand(4));
584 }
585 
SplitRes_UNDEF(SDNode * N,SDValue & Lo,SDValue & Hi)586 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
587   EVT LoVT, HiVT;
588   std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(N->getValueType(0));
589   Lo = DAG.getUNDEF(LoVT);
590   Hi = DAG.getUNDEF(HiVT);
591 }
592 
SplitVecRes_AssertZext(SDNode * N,SDValue & Lo,SDValue & Hi)593 void DAGTypeLegalizer::SplitVecRes_AssertZext(SDNode *N, SDValue &Lo,
594                                               SDValue &Hi) {
595   SDValue L, H;
596   SDLoc dl(N);
597   GetSplitOp(N->getOperand(0), L, H);
598 
599   Lo = DAG.getNode(ISD::AssertZext, dl, L.getValueType(), L, N->getOperand(1));
600   Hi = DAG.getNode(ISD::AssertZext, dl, H.getValueType(), H, N->getOperand(1));
601 }
602 
SplitRes_FREEZE(SDNode * N,SDValue & Lo,SDValue & Hi)603 void DAGTypeLegalizer::SplitRes_FREEZE(SDNode *N, SDValue &Lo, SDValue &Hi) {
604   SDValue L, H;
605   SDLoc dl(N);
606   GetSplitOp(N->getOperand(0), L, H);
607 
608   Lo = DAG.getNode(ISD::FREEZE, dl, L.getValueType(), L);
609   Hi = DAG.getNode(ISD::FREEZE, dl, H.getValueType(), H);
610 }
611 
SplitRes_ARITH_FENCE(SDNode * N,SDValue & Lo,SDValue & Hi)612 void DAGTypeLegalizer::SplitRes_ARITH_FENCE(SDNode *N, SDValue &Lo,
613                                             SDValue &Hi) {
614   SDValue L, H;
615   SDLoc DL(N);
616   GetSplitOp(N->getOperand(0), L, H);
617 
618   Lo = DAG.getNode(ISD::ARITH_FENCE, DL, L.getValueType(), L);
619   Hi = DAG.getNode(ISD::ARITH_FENCE, DL, H.getValueType(), H);
620 }
621