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 //===----------------------------------------------------------------------===//
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];
128 if (TLI.isBigEndian())
131 Vals.push_back(DAG.getNode(ISD::BUILD_PAIR, dl,
134 LHS.getValueType().getSizeInBits() << 1),
140 if (TLI.isBigEndian())
147 // Lower the bit-convert to a store/load from the stack.
148 assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
150 // Create the stack frame object. Make sure it is aligned for both
151 // the source and expanded destination types.
153 TLI.getDataLayout()->getPrefTypeAlignment(NOutVT.
154 getTypeForEVT(*DAG.getContext()));
155 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment);
156 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
157 MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI);
159 // Emit a store to the stack slot.
160 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, PtrInfo,
163 // Load the first half from the stack slot.
164 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, PtrInfo,
165 false, false, false, 0);
167 // Increment the pointer to the other half.
168 unsigned IncrementSize = NOutVT.getSizeInBits() / 8;
169 StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
170 DAG.getIntPtrConstant(IncrementSize));
172 // Load the second half from the stack slot.
173 Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr,
174 PtrInfo.getWithOffset(IncrementSize), false,
175 false, false, MinAlign(Alignment, IncrementSize));
177 // Handle endianness of the load.
178 if (TLI.isBigEndian())
182 void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
184 // Return the operands.
185 Lo = N->getOperand(0);
186 Hi = N->getOperand(1);
189 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
191 GetExpandedOp(N->getOperand(0), Lo, Hi);
192 SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ?
195 assert(Part.getValueType() == N->getValueType(0) &&
196 "Type twice as big as expanded type not itself expanded!");
198 GetPairElements(Part, Lo, Hi);
201 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
203 SDValue OldVec = N->getOperand(0);
204 unsigned OldElts = OldVec.getValueType().getVectorNumElements();
205 EVT OldEltVT = OldVec.getValueType().getVectorElementType();
206 DebugLoc dl = N->getDebugLoc();
208 // Convert to a vector of the expanded element type, for example
209 // <3 x i64> -> <6 x i32>.
210 EVT OldVT = N->getValueType(0);
211 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
213 if (OldVT != OldEltVT) {
214 // The result of EXTRACT_VECTOR_ELT may be larger than the element type of
215 // the input vector. If so, extend the elements of the input vector to the
216 // same bitwidth as the result before expanding.
217 assert(OldEltVT.bitsLT(OldVT) && "Result type smaller then element type!");
218 EVT NVecVT = EVT::getVectorVT(*DAG.getContext(), OldVT, OldElts);
219 OldVec = DAG.getNode(ISD::ANY_EXTEND, dl, NVecVT, N->getOperand(0));
222 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
223 EVT::getVectorVT(*DAG.getContext(),
227 // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector.
228 SDValue Idx = N->getOperand(1);
230 // Make sure the type of Idx is big enough to hold the new values.
231 if (Idx.getValueType().bitsLT(TLI.getPointerTy()))
232 Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
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!");
248 DebugLoc dl = N->getDebugLoc();
250 LoadSDNode *LD = cast<LoadSDNode>(N);
251 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), LD->getValueType(0));
252 SDValue Chain = LD->getChain();
253 SDValue Ptr = LD->getBasePtr();
254 unsigned Alignment = LD->getAlignment();
255 bool isVolatile = LD->isVolatile();
256 bool isNonTemporal = LD->isNonTemporal();
257 bool isInvariant = LD->isInvariant();
259 assert(NVT.isByteSized() && "Expanded type not byte sized!");
261 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getPointerInfo(),
262 isVolatile, isNonTemporal, isInvariant, Alignment);
264 // Increment the pointer to the other half.
265 unsigned IncrementSize = NVT.getSizeInBits() / 8;
266 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
267 DAG.getIntPtrConstant(IncrementSize));
268 Hi = DAG.getLoad(NVT, dl, Chain, Ptr,
269 LD->getPointerInfo().getWithOffset(IncrementSize),
270 isVolatile, isNonTemporal, isInvariant,
271 MinAlign(Alignment, IncrementSize));
273 // Build a factor node to remember that this load is independent of the
275 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
278 // Handle endianness of the load.
279 if (TLI.isBigEndian())
282 // Modified the chain - switch anything that used the old chain to use
284 ReplaceValueWith(SDValue(N, 1), Chain);
287 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
288 EVT OVT = N->getValueType(0);
289 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), OVT);
290 SDValue Chain = N->getOperand(0);
291 SDValue Ptr = N->getOperand(1);
292 DebugLoc dl = N->getDebugLoc();
293 const unsigned Align = N->getConstantOperandVal(3);
295 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2), Align);
296 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2), 0);
298 // Handle endianness of the load.
299 if (TLI.isBigEndian())
302 // Modified the chain - switch anything that used the old chain to use
304 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
308 //===--------------------------------------------------------------------===//
309 // Generic Operand Expansion.
310 //===--------------------------------------------------------------------===//
312 SDValue DAGTypeLegalizer::ExpandOp_BITCAST(SDNode *N) {
313 DebugLoc dl = N->getDebugLoc();
314 if (N->getValueType(0).isVector()) {
315 // An illegal expanding type is being converted to a legal vector type.
316 // Make a two element vector out of the expanded parts and convert that
317 // instead, but only if the new vector type is legal (otherwise there
318 // is no point, and it might create expansion loops). For example, on
319 // x86 this turns v1i64 = BITCAST i64 into v1i64 = BITCAST v2i32.
320 EVT OVT = N->getOperand(0).getValueType();
321 EVT NVT = EVT::getVectorVT(*DAG.getContext(),
322 TLI.getTypeToTransformTo(*DAG.getContext(), OVT),
325 if (isTypeLegal(NVT)) {
327 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]);
329 if (TLI.isBigEndian())
330 std::swap(Parts[0], Parts[1]);
332 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2);
333 return DAG.getNode(ISD::BITCAST, dl, N->getValueType(0), Vec);
337 // Otherwise, store to a temporary and load out again as the new type.
338 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
341 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
342 // The vector type is legal but the element type needs expansion.
343 EVT VecVT = N->getValueType(0);
344 unsigned NumElts = VecVT.getVectorNumElements();
345 EVT OldVT = N->getOperand(0).getValueType();
346 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
347 DebugLoc dl = N->getDebugLoc();
349 assert(OldVT == VecVT.getVectorElementType() &&
350 "BUILD_VECTOR operand type doesn't match vector element type!");
352 // Build a vector of twice the length out of the expanded elements.
353 // For example <3 x i64> -> <6 x i32>.
354 std::vector<SDValue> NewElts;
355 NewElts.reserve(NumElts*2);
357 for (unsigned i = 0; i < NumElts; ++i) {
359 GetExpandedOp(N->getOperand(i), Lo, Hi);
360 if (TLI.isBigEndian())
362 NewElts.push_back(Lo);
363 NewElts.push_back(Hi);
366 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
367 EVT::getVectorVT(*DAG.getContext(),
368 NewVT, NewElts.size()),
369 &NewElts[0], NewElts.size());
371 // Convert the new vector to the old vector type.
372 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
375 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
377 GetExpandedOp(N->getOperand(0), Lo, Hi);
378 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
381 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
382 // The vector type is legal but the element type needs expansion.
383 EVT VecVT = N->getValueType(0);
384 unsigned NumElts = VecVT.getVectorNumElements();
385 DebugLoc dl = N->getDebugLoc();
387 SDValue Val = N->getOperand(1);
388 EVT OldEVT = Val.getValueType();
389 EVT NewEVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldEVT);
391 assert(OldEVT == VecVT.getVectorElementType() &&
392 "Inserted element type doesn't match vector element type!");
394 // Bitconvert to a vector of twice the length with elements of the expanded
395 // type, insert the expanded vector elements, and then convert back.
396 EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewEVT, NumElts*2);
397 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
398 NewVecVT, N->getOperand(0));
401 GetExpandedOp(Val, Lo, Hi);
402 if (TLI.isBigEndian())
405 SDValue Idx = N->getOperand(2);
406 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
407 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
408 Idx = DAG.getNode(ISD::ADD, dl,
409 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1));
410 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
412 // Convert the new vector to the old vector type.
413 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
416 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
417 DebugLoc dl = N->getDebugLoc();
418 EVT VT = N->getValueType(0);
419 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
420 "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
421 unsigned NumElts = VT.getVectorNumElements();
422 SmallVector<SDValue, 16> Ops(NumElts);
423 Ops[0] = N->getOperand(0);
424 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
425 for (unsigned i = 1; i < NumElts; ++i)
427 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts);
430 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
431 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
432 assert(OpNo == 1 && "Can only expand the stored value so far");
433 DebugLoc dl = N->getDebugLoc();
435 StoreSDNode *St = cast<StoreSDNode>(N);
436 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(),
437 St->getValue().getValueType());
438 SDValue Chain = St->getChain();
439 SDValue Ptr = St->getBasePtr();
440 unsigned Alignment = St->getAlignment();
441 bool isVolatile = St->isVolatile();
442 bool isNonTemporal = St->isNonTemporal();
444 assert(NVT.isByteSized() && "Expanded type not byte sized!");
445 unsigned IncrementSize = NVT.getSizeInBits() / 8;
448 GetExpandedOp(St->getValue(), Lo, Hi);
450 if (TLI.isBigEndian())
453 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getPointerInfo(),
454 isVolatile, isNonTemporal, Alignment);
456 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
457 DAG.getIntPtrConstant(IncrementSize));
458 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!");
459 Hi = DAG.getStore(Chain, dl, Hi, Ptr,
460 St->getPointerInfo().getWithOffset(IncrementSize),
461 isVolatile, isNonTemporal,
462 MinAlign(Alignment, IncrementSize));
464 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
468 //===--------------------------------------------------------------------===//
469 // Generic Result Splitting.
470 //===--------------------------------------------------------------------===//
472 // Be careful to make no assumptions about which of Lo/Hi is stored first in
473 // memory (for vectors it is always Lo first followed by Hi in the following
474 // bytes; for integers and floats it is Lo first if and only if the machine is
477 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
478 SDValue &Lo, SDValue &Hi) {
479 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
480 GetSplitOp(Op, Lo, Hi);
483 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
485 SDValue LL, LH, RL, RH, CL, CH;
486 DebugLoc dl = N->getDebugLoc();
487 GetSplitOp(N->getOperand(1), LL, LH);
488 GetSplitOp(N->getOperand(2), RL, RH);
490 SDValue Cond = N->getOperand(0);
492 if (Cond.getValueType().isVector()) {
493 assert(Cond.getValueType().getVectorElementType() == MVT::i1 &&
494 "Condition legalized before result?");
495 unsigned NumElements = Cond.getValueType().getVectorNumElements();
496 EVT VCondTy = EVT::getVectorVT(*DAG.getContext(), MVT::i1, NumElements / 2);
497 CL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
498 DAG.getIntPtrConstant(0));
499 CH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
500 DAG.getIntPtrConstant(NumElements / 2));
503 Lo = DAG.getNode(N->getOpcode(), dl, LL.getValueType(), CL, LL, RL);
504 Hi = DAG.getNode(N->getOpcode(), dl, LH.getValueType(), CH, LH, RH);
507 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
509 SDValue LL, LH, RL, RH;
510 DebugLoc dl = N->getDebugLoc();
511 GetSplitOp(N->getOperand(2), LL, LH);
512 GetSplitOp(N->getOperand(3), RL, RH);
514 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
515 N->getOperand(1), LL, RL, N->getOperand(4));
516 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
517 N->getOperand(1), LH, RH, N->getOperand(4));
520 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
522 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
523 Lo = DAG.getUNDEF(LoVT);
524 Hi = DAG.getUNDEF(HiVT);