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/DataLayout.h"
26 //===----------------------------------------------------------------------===//
27 // Generic Result Expansion.
28 //===----------------------------------------------------------------------===//
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.
33 void 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);
39 void 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();
46 // Handle some special cases efficiently.
47 switch (getTypeAction(InVT)) {
48 case TargetLowering::TypeLegal:
49 case TargetLowering::TypePromoteInteger:
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);
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);
64 case TargetLowering::TypeSplitVector:
65 GetSplitVector(InOp, Lo, Hi);
66 if (TLI.isBigEndian())
68 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
69 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
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);
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())
88 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
89 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
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 unsigned NumElems = 2;
99 EVT NVT = EVT::getVectorVT(*DAG.getContext(), ElemVT, NumElems);
101 // If <ElemVT * N> is not a legal type, try <ElemVT/2 * (N*2)>.
102 while (!isTypeLegal(NVT)) {
103 unsigned NewSizeInBits = ElemVT.getSizeInBits() / 2;
104 // If the element size is smaller than byte, bail.
105 if (NewSizeInBits < 8)
108 ElemVT = EVT::getIntegerVT(*DAG.getContext(), NewSizeInBits);
109 NVT = EVT::getVectorVT(*DAG.getContext(), ElemVT, NumElems);
112 if (isTypeLegal(NVT)) {
113 SDValue CastInOp = DAG.getNode(ISD::BITCAST, dl, NVT, InOp);
115 SmallVector<SDValue, 8> Vals;
116 for (unsigned i = 0; i < NumElems; ++i)
117 Vals.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, ElemVT,
118 CastInOp, DAG.getIntPtrConstant(i)));
120 // Build Lo, Hi pair by pairing extracted elements if needed.
122 for (unsigned e = Vals.size(); e - Slot > 2; Slot += 2, e += 1) {
123 // Each iteration will BUILD_PAIR two nodes and append the result until
124 // there are only two nodes left, i.e. Lo and Hi.
125 SDValue LHS = Vals[Slot];
126 SDValue RHS = Vals[Slot + 1];
127 Vals.push_back(DAG.getNode(ISD::BUILD_PAIR, dl,
130 LHS.getValueType().getSizeInBits() << 1),
136 if (TLI.isBigEndian())
143 // Lower the bit-convert to a store/load from the stack.
144 assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
146 // Create the stack frame object. Make sure it is aligned for both
147 // the source and expanded destination types.
149 TLI.getDataLayout()->getPrefTypeAlignment(NOutVT.
150 getTypeForEVT(*DAG.getContext()));
151 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment);
152 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
153 MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI);
155 // Emit a store to the stack slot.
156 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, PtrInfo,
159 // Load the first half from the stack slot.
160 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, PtrInfo,
161 false, false, false, 0);
163 // Increment the pointer to the other half.
164 unsigned IncrementSize = NOutVT.getSizeInBits() / 8;
165 StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
166 DAG.getIntPtrConstant(IncrementSize));
168 // Load the second half from the stack slot.
169 Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr,
170 PtrInfo.getWithOffset(IncrementSize), false,
171 false, false, MinAlign(Alignment, IncrementSize));
173 // Handle endianness of the load.
174 if (TLI.isBigEndian())
178 void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
180 // Return the operands.
181 Lo = N->getOperand(0);
182 Hi = N->getOperand(1);
185 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
187 GetExpandedOp(N->getOperand(0), Lo, Hi);
188 SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ?
191 assert(Part.getValueType() == N->getValueType(0) &&
192 "Type twice as big as expanded type not itself expanded!");
194 GetPairElements(Part, Lo, Hi);
197 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
199 SDValue OldVec = N->getOperand(0);
200 unsigned OldElts = OldVec.getValueType().getVectorNumElements();
201 EVT OldEltVT = OldVec.getValueType().getVectorElementType();
202 DebugLoc dl = N->getDebugLoc();
204 // Convert to a vector of the expanded element type, for example
205 // <3 x i64> -> <6 x i32>.
206 EVT OldVT = N->getValueType(0);
207 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
209 if (OldVT != OldEltVT) {
210 // The result of EXTRACT_VECTOR_ELT may be larger than the element type of
211 // the input vector. If so, extend the elements of the input vector to the
212 // same bitwidth as the result before expanding.
213 assert(OldEltVT.bitsLT(OldVT) && "Result type smaller then element type!");
214 EVT NVecVT = EVT::getVectorVT(*DAG.getContext(), OldVT, OldElts);
215 OldVec = DAG.getNode(ISD::ANY_EXTEND, dl, NVecVT, N->getOperand(0));
218 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
219 EVT::getVectorVT(*DAG.getContext(),
223 // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector.
224 SDValue Idx = N->getOperand(1);
226 // Make sure the type of Idx is big enough to hold the new values.
227 if (Idx.getValueType().bitsLT(TLI.getPointerTy()))
228 Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
230 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
231 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
233 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
234 DAG.getConstant(1, Idx.getValueType()));
235 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
237 if (TLI.isBigEndian())
241 void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo,
243 assert(ISD::isNormalLoad(N) && "This routine only for normal loads!");
244 DebugLoc dl = N->getDebugLoc();
246 LoadSDNode *LD = cast<LoadSDNode>(N);
247 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), LD->getValueType(0));
248 SDValue Chain = LD->getChain();
249 SDValue Ptr = LD->getBasePtr();
250 unsigned Alignment = LD->getAlignment();
251 bool isVolatile = LD->isVolatile();
252 bool isNonTemporal = LD->isNonTemporal();
253 bool isInvariant = LD->isInvariant();
255 assert(NVT.isByteSized() && "Expanded type not byte sized!");
257 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getPointerInfo(),
258 isVolatile, isNonTemporal, isInvariant, Alignment);
260 // Increment the pointer to the other half.
261 unsigned IncrementSize = NVT.getSizeInBits() / 8;
262 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
263 DAG.getIntPtrConstant(IncrementSize));
264 Hi = DAG.getLoad(NVT, dl, Chain, Ptr,
265 LD->getPointerInfo().getWithOffset(IncrementSize),
266 isVolatile, isNonTemporal, isInvariant,
267 MinAlign(Alignment, IncrementSize));
269 // Build a factor node to remember that this load is independent of the
271 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
274 // Handle endianness of the load.
275 if (TLI.isBigEndian())
278 // Modified the chain - switch anything that used the old chain to use
280 ReplaceValueWith(SDValue(N, 1), Chain);
283 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
284 EVT OVT = N->getValueType(0);
285 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), OVT);
286 SDValue Chain = N->getOperand(0);
287 SDValue Ptr = N->getOperand(1);
288 DebugLoc dl = N->getDebugLoc();
289 const unsigned Align = N->getConstantOperandVal(3);
291 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2), Align);
292 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2), 0);
294 // Handle endianness of the load.
295 if (TLI.isBigEndian())
298 // Modified the chain - switch anything that used the old chain to use
300 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
304 //===--------------------------------------------------------------------===//
305 // Generic Operand Expansion.
306 //===--------------------------------------------------------------------===//
308 SDValue DAGTypeLegalizer::ExpandOp_BITCAST(SDNode *N) {
309 DebugLoc dl = N->getDebugLoc();
310 if (N->getValueType(0).isVector()) {
311 // An illegal expanding type is being converted to a legal vector type.
312 // Make a two element vector out of the expanded parts and convert that
313 // instead, but only if the new vector type is legal (otherwise there
314 // is no point, and it might create expansion loops). For example, on
315 // x86 this turns v1i64 = BITCAST i64 into v1i64 = BITCAST v2i32.
316 EVT OVT = N->getOperand(0).getValueType();
317 EVT NVT = EVT::getVectorVT(*DAG.getContext(),
318 TLI.getTypeToTransformTo(*DAG.getContext(), OVT),
321 if (isTypeLegal(NVT)) {
323 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]);
325 if (TLI.isBigEndian())
326 std::swap(Parts[0], Parts[1]);
328 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2);
329 return DAG.getNode(ISD::BITCAST, dl, N->getValueType(0), Vec);
333 // Otherwise, store to a temporary and load out again as the new type.
334 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
337 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
338 // The vector type is legal but the element type needs expansion.
339 EVT VecVT = N->getValueType(0);
340 unsigned NumElts = VecVT.getVectorNumElements();
341 EVT OldVT = N->getOperand(0).getValueType();
342 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
343 DebugLoc dl = N->getDebugLoc();
345 assert(OldVT == VecVT.getVectorElementType() &&
346 "BUILD_VECTOR operand type doesn't match vector element type!");
348 // Build a vector of twice the length out of the expanded elements.
349 // For example <3 x i64> -> <6 x i32>.
350 std::vector<SDValue> NewElts;
351 NewElts.reserve(NumElts*2);
353 for (unsigned i = 0; i < NumElts; ++i) {
355 GetExpandedOp(N->getOperand(i), Lo, Hi);
356 if (TLI.isBigEndian())
358 NewElts.push_back(Lo);
359 NewElts.push_back(Hi);
362 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
363 EVT::getVectorVT(*DAG.getContext(),
364 NewVT, NewElts.size()),
365 &NewElts[0], NewElts.size());
367 // Convert the new vector to the old vector type.
368 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
371 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
373 GetExpandedOp(N->getOperand(0), Lo, Hi);
374 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
377 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
378 // The vector type is legal but the element type needs expansion.
379 EVT VecVT = N->getValueType(0);
380 unsigned NumElts = VecVT.getVectorNumElements();
381 DebugLoc dl = N->getDebugLoc();
383 SDValue Val = N->getOperand(1);
384 EVT OldEVT = Val.getValueType();
385 EVT NewEVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldEVT);
387 assert(OldEVT == VecVT.getVectorElementType() &&
388 "Inserted element type doesn't match vector element type!");
390 // Bitconvert to a vector of twice the length with elements of the expanded
391 // type, insert the expanded vector elements, and then convert back.
392 EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewEVT, NumElts*2);
393 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
394 NewVecVT, N->getOperand(0));
397 GetExpandedOp(Val, Lo, Hi);
398 if (TLI.isBigEndian())
401 SDValue Idx = N->getOperand(2);
402 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
403 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
404 Idx = DAG.getNode(ISD::ADD, dl,
405 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1));
406 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
408 // Convert the new vector to the old vector type.
409 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
412 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
413 DebugLoc dl = N->getDebugLoc();
414 EVT VT = N->getValueType(0);
415 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
416 "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
417 unsigned NumElts = VT.getVectorNumElements();
418 SmallVector<SDValue, 16> Ops(NumElts);
419 Ops[0] = N->getOperand(0);
420 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
421 for (unsigned i = 1; i < NumElts; ++i)
423 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts);
426 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
427 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
428 assert(OpNo == 1 && "Can only expand the stored value so far");
429 DebugLoc dl = N->getDebugLoc();
431 StoreSDNode *St = cast<StoreSDNode>(N);
432 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(),
433 St->getValue().getValueType());
434 SDValue Chain = St->getChain();
435 SDValue Ptr = St->getBasePtr();
436 unsigned Alignment = St->getAlignment();
437 bool isVolatile = St->isVolatile();
438 bool isNonTemporal = St->isNonTemporal();
440 assert(NVT.isByteSized() && "Expanded type not byte sized!");
441 unsigned IncrementSize = NVT.getSizeInBits() / 8;
444 GetExpandedOp(St->getValue(), Lo, Hi);
446 if (TLI.isBigEndian())
449 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getPointerInfo(),
450 isVolatile, isNonTemporal, Alignment);
452 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
453 DAG.getIntPtrConstant(IncrementSize));
454 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!");
455 Hi = DAG.getStore(Chain, dl, Hi, Ptr,
456 St->getPointerInfo().getWithOffset(IncrementSize),
457 isVolatile, isNonTemporal,
458 MinAlign(Alignment, IncrementSize));
460 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
464 //===--------------------------------------------------------------------===//
465 // Generic Result Splitting.
466 //===--------------------------------------------------------------------===//
468 // Be careful to make no assumptions about which of Lo/Hi is stored first in
469 // memory (for vectors it is always Lo first followed by Hi in the following
470 // bytes; for integers and floats it is Lo first if and only if the machine is
473 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
474 SDValue &Lo, SDValue &Hi) {
475 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
476 GetSplitOp(Op, Lo, Hi);
479 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
481 SDValue LL, LH, RL, RH, CL, CH;
482 DebugLoc dl = N->getDebugLoc();
483 GetSplitOp(N->getOperand(1), LL, LH);
484 GetSplitOp(N->getOperand(2), RL, RH);
486 SDValue Cond = N->getOperand(0);
488 if (Cond.getValueType().isVector()) {
489 assert(Cond.getValueType().getVectorElementType() == MVT::i1 &&
490 "Condition legalized before result?");
491 unsigned NumElements = Cond.getValueType().getVectorNumElements();
492 EVT VCondTy = EVT::getVectorVT(*DAG.getContext(), MVT::i1, NumElements / 2);
493 CL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
494 DAG.getIntPtrConstant(0));
495 CH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
496 DAG.getIntPtrConstant(NumElements / 2));
499 Lo = DAG.getNode(N->getOpcode(), dl, LL.getValueType(), CL, LL, RL);
500 Hi = DAG.getNode(N->getOpcode(), dl, LH.getValueType(), CH, LH, RH);
503 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
505 SDValue LL, LH, RL, RH;
506 DebugLoc dl = N->getDebugLoc();
507 GetSplitOp(N->getOperand(2), LL, LH);
508 GetSplitOp(N->getOperand(3), RL, RH);
510 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
511 N->getOperand(1), LL, RL, N->getOperand(4));
512 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
513 N->getOperand(1), LH, RH, N->getOperand(4));
516 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
518 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
519 Lo = DAG.getUNDEF(LoVT);
520 Hi = DAG.getUNDEF(HiVT);