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/Target/TargetData.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;
98 EVT NVT = EVT::getVectorVT(*DAG.getContext(), NOutVT, NumElems);
100 // If <NOutVT * N> is not a legal type, try <NOutVT/2 * (N*2)>.
101 while (!isTypeLegal(NVT)) {
102 unsigned NewSizeInBits = NOutVT.getSizeInBits() / 2;
103 // If the element size is smaller than byte, bail.
104 if (NewSizeInBits < 8)
107 NOutVT = EVT::getIntegerVT(*DAG.getContext(), NewSizeInBits);
108 NVT = EVT::getVectorVT(*DAG.getContext(), NOutVT, NumElems);
111 if (isTypeLegal(NVT)) {
112 SDValue CastInOp = DAG.getNode(ISD::BITCAST, dl, NVT, InOp);
114 SmallVector<SDValue, 8> Vals;
115 for (unsigned i = 0; i < NumElems; ++i)
116 Vals.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT,
117 CastInOp, DAG.getIntPtrConstant(i)));
119 // Build Lo, Hi pair by pairing extracted elements if needed.
121 for (unsigned e = Vals.size(); e - Slot > 2; Slot += 2, e += 1) {
122 // Each iteration will BUILD_PAIR two nodes and append the result until
123 // there are only two nodes left, i.e. Lo and Hi.
124 SDValue LHS = Vals[Slot];
125 SDValue RHS = Vals[Slot + 1];
126 Vals.push_back(DAG.getNode(ISD::BUILD_PAIR, dl,
129 LHS.getValueType().getSizeInBits() << 1),
135 if (TLI.isBigEndian())
142 // Lower the bit-convert to a store/load from the stack.
143 assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
145 // Create the stack frame object. Make sure it is aligned for both
146 // the source and expanded destination types.
148 TLI.getTargetData()->getPrefTypeAlignment(NOutVT.
149 getTypeForEVT(*DAG.getContext()));
150 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment);
151 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
152 MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI);
154 // Emit a store to the stack slot.
155 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, PtrInfo,
158 // Load the first half from the stack slot.
159 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, PtrInfo,
160 false, false, false, 0);
162 // Increment the pointer to the other half.
163 unsigned IncrementSize = NOutVT.getSizeInBits() / 8;
164 StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
165 DAG.getIntPtrConstant(IncrementSize));
167 // Load the second half from the stack slot.
168 Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr,
169 PtrInfo.getWithOffset(IncrementSize), false,
170 false, false, MinAlign(Alignment, IncrementSize));
172 // Handle endianness of the load.
173 if (TLI.isBigEndian())
177 void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
179 // Return the operands.
180 Lo = N->getOperand(0);
181 Hi = N->getOperand(1);
184 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
186 GetExpandedOp(N->getOperand(0), Lo, Hi);
187 SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ?
190 assert(Part.getValueType() == N->getValueType(0) &&
191 "Type twice as big as expanded type not itself expanded!");
193 GetPairElements(Part, Lo, Hi);
196 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
198 SDValue OldVec = N->getOperand(0);
199 unsigned OldElts = OldVec.getValueType().getVectorNumElements();
200 EVT OldEltVT = OldVec.getValueType().getVectorElementType();
201 DebugLoc dl = N->getDebugLoc();
203 // Convert to a vector of the expanded element type, for example
204 // <3 x i64> -> <6 x i32>.
205 EVT OldVT = N->getValueType(0);
206 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
208 if (OldVT != OldEltVT) {
209 // The result of EXTRACT_VECTOR_ELT may be larger than the element type of
210 // the input vector. If so, extend the elements of the input vector to the
211 // same bitwidth as the result before expanding.
212 assert(OldEltVT.bitsLT(OldVT) && "Result type smaller then element type!");
213 EVT NVecVT = EVT::getVectorVT(*DAG.getContext(), OldVT, OldElts);
214 OldVec = DAG.getNode(ISD::ANY_EXTEND, dl, NVecVT, N->getOperand(0));
217 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
218 EVT::getVectorVT(*DAG.getContext(),
222 // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector.
223 SDValue Idx = N->getOperand(1);
225 // Make sure the type of Idx is big enough to hold the new values.
226 if (Idx.getValueType().bitsLT(TLI.getPointerTy()))
227 Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
229 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
230 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
232 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
233 DAG.getConstant(1, Idx.getValueType()));
234 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
236 if (TLI.isBigEndian())
240 void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo,
242 assert(ISD::isNormalLoad(N) && "This routine only for normal loads!");
243 DebugLoc dl = N->getDebugLoc();
245 LoadSDNode *LD = cast<LoadSDNode>(N);
246 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), LD->getValueType(0));
247 SDValue Chain = LD->getChain();
248 SDValue Ptr = LD->getBasePtr();
249 unsigned Alignment = LD->getAlignment();
250 bool isVolatile = LD->isVolatile();
251 bool isNonTemporal = LD->isNonTemporal();
252 bool isInvariant = LD->isInvariant();
254 assert(NVT.isByteSized() && "Expanded type not byte sized!");
256 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getPointerInfo(),
257 isVolatile, isNonTemporal, isInvariant, Alignment);
259 // Increment the pointer to the other half.
260 unsigned IncrementSize = NVT.getSizeInBits() / 8;
261 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
262 DAG.getIntPtrConstant(IncrementSize));
263 Hi = DAG.getLoad(NVT, dl, Chain, Ptr,
264 LD->getPointerInfo().getWithOffset(IncrementSize),
265 isVolatile, isNonTemporal, isInvariant,
266 MinAlign(Alignment, IncrementSize));
268 // Build a factor node to remember that this load is independent of the
270 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
273 // Handle endianness of the load.
274 if (TLI.isBigEndian())
277 // Modified the chain - switch anything that used the old chain to use
279 ReplaceValueWith(SDValue(N, 1), Chain);
282 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
283 EVT OVT = N->getValueType(0);
284 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), OVT);
285 SDValue Chain = N->getOperand(0);
286 SDValue Ptr = N->getOperand(1);
287 DebugLoc dl = N->getDebugLoc();
288 const unsigned Align = N->getConstantOperandVal(3);
290 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2), Align);
291 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2), 0);
293 // Handle endianness of the load.
294 if (TLI.isBigEndian())
297 // Modified the chain - switch anything that used the old chain to use
299 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
303 //===--------------------------------------------------------------------===//
304 // Generic Operand Expansion.
305 //===--------------------------------------------------------------------===//
307 SDValue DAGTypeLegalizer::ExpandOp_BITCAST(SDNode *N) {
308 DebugLoc dl = N->getDebugLoc();
309 if (N->getValueType(0).isVector()) {
310 // An illegal expanding type is being converted to a legal vector type.
311 // Make a two element vector out of the expanded parts and convert that
312 // instead, but only if the new vector type is legal (otherwise there
313 // is no point, and it might create expansion loops). For example, on
314 // x86 this turns v1i64 = BITCAST i64 into v1i64 = BITCAST v2i32.
315 EVT OVT = N->getOperand(0).getValueType();
316 EVT NVT = EVT::getVectorVT(*DAG.getContext(),
317 TLI.getTypeToTransformTo(*DAG.getContext(), OVT),
320 if (isTypeLegal(NVT)) {
322 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]);
324 if (TLI.isBigEndian())
325 std::swap(Parts[0], Parts[1]);
327 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2);
328 return DAG.getNode(ISD::BITCAST, dl, N->getValueType(0), Vec);
332 // Otherwise, store to a temporary and load out again as the new type.
333 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
336 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
337 // The vector type is legal but the element type needs expansion.
338 EVT VecVT = N->getValueType(0);
339 unsigned NumElts = VecVT.getVectorNumElements();
340 EVT OldVT = N->getOperand(0).getValueType();
341 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
342 DebugLoc dl = N->getDebugLoc();
344 assert(OldVT == VecVT.getVectorElementType() &&
345 "BUILD_VECTOR operand type doesn't match vector element type!");
347 // Build a vector of twice the length out of the expanded elements.
348 // For example <3 x i64> -> <6 x i32>.
349 std::vector<SDValue> NewElts;
350 NewElts.reserve(NumElts*2);
352 for (unsigned i = 0; i < NumElts; ++i) {
354 GetExpandedOp(N->getOperand(i), Lo, Hi);
355 if (TLI.isBigEndian())
357 NewElts.push_back(Lo);
358 NewElts.push_back(Hi);
361 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
362 EVT::getVectorVT(*DAG.getContext(),
363 NewVT, NewElts.size()),
364 &NewElts[0], NewElts.size());
366 // Convert the new vector to the old vector type.
367 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
370 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
372 GetExpandedOp(N->getOperand(0), Lo, Hi);
373 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
376 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
377 // The vector type is legal but the element type needs expansion.
378 EVT VecVT = N->getValueType(0);
379 unsigned NumElts = VecVT.getVectorNumElements();
380 DebugLoc dl = N->getDebugLoc();
382 SDValue Val = N->getOperand(1);
383 EVT OldEVT = Val.getValueType();
384 EVT NewEVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldEVT);
386 assert(OldEVT == VecVT.getVectorElementType() &&
387 "Inserted element type doesn't match vector element type!");
389 // Bitconvert to a vector of twice the length with elements of the expanded
390 // type, insert the expanded vector elements, and then convert back.
391 EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewEVT, NumElts*2);
392 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
393 NewVecVT, N->getOperand(0));
396 GetExpandedOp(Val, Lo, Hi);
397 if (TLI.isBigEndian())
400 SDValue Idx = N->getOperand(2);
401 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
402 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
403 Idx = DAG.getNode(ISD::ADD, dl,
404 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1));
405 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
407 // Convert the new vector to the old vector type.
408 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
411 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
412 DebugLoc dl = N->getDebugLoc();
413 EVT VT = N->getValueType(0);
414 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
415 "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
416 unsigned NumElts = VT.getVectorNumElements();
417 SmallVector<SDValue, 16> Ops(NumElts);
418 Ops[0] = N->getOperand(0);
419 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
420 for (unsigned i = 1; i < NumElts; ++i)
422 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts);
425 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
426 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
427 assert(OpNo == 1 && "Can only expand the stored value so far");
428 DebugLoc dl = N->getDebugLoc();
430 StoreSDNode *St = cast<StoreSDNode>(N);
431 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(),
432 St->getValue().getValueType());
433 SDValue Chain = St->getChain();
434 SDValue Ptr = St->getBasePtr();
435 unsigned Alignment = St->getAlignment();
436 bool isVolatile = St->isVolatile();
437 bool isNonTemporal = St->isNonTemporal();
439 assert(NVT.isByteSized() && "Expanded type not byte sized!");
440 unsigned IncrementSize = NVT.getSizeInBits() / 8;
443 GetExpandedOp(St->getValue(), Lo, Hi);
445 if (TLI.isBigEndian())
448 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getPointerInfo(),
449 isVolatile, isNonTemporal, Alignment);
451 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
452 DAG.getIntPtrConstant(IncrementSize));
453 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!");
454 Hi = DAG.getStore(Chain, dl, Hi, Ptr,
455 St->getPointerInfo().getWithOffset(IncrementSize),
456 isVolatile, isNonTemporal,
457 MinAlign(Alignment, IncrementSize));
459 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
463 //===--------------------------------------------------------------------===//
464 // Generic Result Splitting.
465 //===--------------------------------------------------------------------===//
467 // Be careful to make no assumptions about which of Lo/Hi is stored first in
468 // memory (for vectors it is always Lo first followed by Hi in the following
469 // bytes; for integers and floats it is Lo first if and only if the machine is
472 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
473 SDValue &Lo, SDValue &Hi) {
474 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
475 GetSplitOp(Op, Lo, Hi);
478 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
480 SDValue LL, LH, RL, RH, CL, CH;
481 DebugLoc dl = N->getDebugLoc();
482 GetSplitOp(N->getOperand(1), LL, LH);
483 GetSplitOp(N->getOperand(2), RL, RH);
485 SDValue Cond = N->getOperand(0);
487 if (Cond.getValueType().isVector()) {
488 assert(Cond.getValueType().getVectorElementType() == MVT::i1 &&
489 "Condition legalized before result?");
490 unsigned NumElements = Cond.getValueType().getVectorNumElements();
491 EVT VCondTy = EVT::getVectorVT(*DAG.getContext(), MVT::i1, NumElements / 2);
492 CL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
493 DAG.getIntPtrConstant(0));
494 CH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
495 DAG.getIntPtrConstant(NumElements / 2));
498 Lo = DAG.getNode(N->getOpcode(), dl, LL.getValueType(), CL, LL, RL);
499 Hi = DAG.getNode(N->getOpcode(), dl, LH.getValueType(), CH, LH, RH);
502 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
504 SDValue LL, LH, RL, RH;
505 DebugLoc dl = N->getDebugLoc();
506 GetSplitOp(N->getOperand(2), LL, LH);
507 GetSplitOp(N->getOperand(3), RL, RH);
509 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
510 N->getOperand(1), LL, RL, N->getOperand(4));
511 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
512 N->getOperand(1), LH, RH, N->getOperand(4));
515 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
517 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
518 Lo = DAG.getUNDEF(LoVT);
519 Hi = DAG.getUNDEF(HiVT);