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 EVT NVT = EVT::getVectorVT(*DAG.getContext(), NOutVT, 2);
99 if (isTypeLegal(NVT)) {
100 SDValue CastInOp = DAG.getNode(ISD::BITCAST, dl, NVT, InOp);
101 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp,
102 DAG.getIntPtrConstant(0));
103 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp,
104 DAG.getIntPtrConstant(1));
106 if (TLI.isBigEndian())
113 // Lower the bit-convert to a store/load from the stack.
114 assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
116 // Create the stack frame object. Make sure it is aligned for both
117 // the source and expanded destination types.
119 TLI.getTargetData()->getPrefTypeAlignment(NOutVT.
120 getTypeForEVT(*DAG.getContext()));
121 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment);
122 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
123 MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI);
125 // Emit a store to the stack slot.
126 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, PtrInfo,
129 // Load the first half from the stack slot.
130 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, PtrInfo,
131 false, false, false, 0);
133 // Increment the pointer to the other half.
134 unsigned IncrementSize = NOutVT.getSizeInBits() / 8;
135 StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
136 DAG.getIntPtrConstant(IncrementSize));
138 // Load the second half from the stack slot.
139 Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr,
140 PtrInfo.getWithOffset(IncrementSize), false,
141 false, false, MinAlign(Alignment, IncrementSize));
143 // Handle endianness of the load.
144 if (TLI.isBigEndian())
148 void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
150 // Return the operands.
151 Lo = N->getOperand(0);
152 Hi = N->getOperand(1);
155 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
157 GetExpandedOp(N->getOperand(0), Lo, Hi);
158 SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ?
161 assert(Part.getValueType() == N->getValueType(0) &&
162 "Type twice as big as expanded type not itself expanded!");
164 GetPairElements(Part, Lo, Hi);
167 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
169 SDValue OldVec = N->getOperand(0);
170 unsigned OldElts = OldVec.getValueType().getVectorNumElements();
171 EVT OldEltVT = OldVec.getValueType().getVectorElementType();
172 DebugLoc dl = N->getDebugLoc();
174 // Convert to a vector of the expanded element type, for example
175 // <3 x i64> -> <6 x i32>.
176 EVT OldVT = N->getValueType(0);
177 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
179 if (OldVT != OldEltVT) {
180 // The result of EXTRACT_VECTOR_ELT may be larger than the element type of
181 // the input vector. If so, extend the elements of the input vector to the
182 // same bitwidth as the result before expanding.
183 assert(OldEltVT.bitsLT(OldVT) && "Result type smaller then element type!");
184 EVT NVecVT = EVT::getVectorVT(*DAG.getContext(), OldVT, OldElts);
185 OldVec = DAG.getNode(ISD::ANY_EXTEND, dl, NVecVT, N->getOperand(0));
188 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
189 EVT::getVectorVT(*DAG.getContext(),
193 // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector.
194 SDValue Idx = N->getOperand(1);
196 // Make sure the type of Idx is big enough to hold the new values.
197 if (Idx.getValueType().bitsLT(TLI.getPointerTy()))
198 Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
200 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
201 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
203 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
204 DAG.getConstant(1, Idx.getValueType()));
205 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
207 if (TLI.isBigEndian())
211 void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo,
213 assert(ISD::isNormalLoad(N) && "This routine only for normal loads!");
214 DebugLoc dl = N->getDebugLoc();
216 LoadSDNode *LD = cast<LoadSDNode>(N);
217 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), LD->getValueType(0));
218 SDValue Chain = LD->getChain();
219 SDValue Ptr = LD->getBasePtr();
220 unsigned Alignment = LD->getAlignment();
221 bool isVolatile = LD->isVolatile();
222 bool isNonTemporal = LD->isNonTemporal();
223 bool isInvariant = LD->isInvariant();
225 assert(NVT.isByteSized() && "Expanded type not byte sized!");
227 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getPointerInfo(),
228 isVolatile, isNonTemporal, isInvariant, Alignment);
230 // Increment the pointer to the other half.
231 unsigned IncrementSize = NVT.getSizeInBits() / 8;
232 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
233 DAG.getIntPtrConstant(IncrementSize));
234 Hi = DAG.getLoad(NVT, dl, Chain, Ptr,
235 LD->getPointerInfo().getWithOffset(IncrementSize),
236 isVolatile, isNonTemporal, isInvariant,
237 MinAlign(Alignment, IncrementSize));
239 // Build a factor node to remember that this load is independent of the
241 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
244 // Handle endianness of the load.
245 if (TLI.isBigEndian())
248 // Modified the chain - switch anything that used the old chain to use
250 ReplaceValueWith(SDValue(N, 1), Chain);
253 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
254 EVT OVT = N->getValueType(0);
255 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), OVT);
256 SDValue Chain = N->getOperand(0);
257 SDValue Ptr = N->getOperand(1);
258 DebugLoc dl = N->getDebugLoc();
259 const unsigned Align = N->getConstantOperandVal(3);
261 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2), Align);
262 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2), 0);
264 // Handle endianness of the load.
265 if (TLI.isBigEndian())
268 // Modified the chain - switch anything that used the old chain to use
270 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
274 //===--------------------------------------------------------------------===//
275 // Generic Operand Expansion.
276 //===--------------------------------------------------------------------===//
278 SDValue DAGTypeLegalizer::ExpandOp_BITCAST(SDNode *N) {
279 DebugLoc dl = N->getDebugLoc();
280 if (N->getValueType(0).isVector()) {
281 // An illegal expanding type is being converted to a legal vector type.
282 // Make a two element vector out of the expanded parts and convert that
283 // instead, but only if the new vector type is legal (otherwise there
284 // is no point, and it might create expansion loops). For example, on
285 // x86 this turns v1i64 = BITCAST i64 into v1i64 = BITCAST v2i32.
286 EVT OVT = N->getOperand(0).getValueType();
287 EVT NVT = EVT::getVectorVT(*DAG.getContext(),
288 TLI.getTypeToTransformTo(*DAG.getContext(), OVT),
291 if (isTypeLegal(NVT)) {
293 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]);
295 if (TLI.isBigEndian())
296 std::swap(Parts[0], Parts[1]);
298 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2);
299 return DAG.getNode(ISD::BITCAST, dl, N->getValueType(0), Vec);
303 // Otherwise, store to a temporary and load out again as the new type.
304 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
307 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
308 // The vector type is legal but the element type needs expansion.
309 EVT VecVT = N->getValueType(0);
310 unsigned NumElts = VecVT.getVectorNumElements();
311 EVT OldVT = N->getOperand(0).getValueType();
312 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
313 DebugLoc dl = N->getDebugLoc();
315 assert(OldVT == VecVT.getVectorElementType() &&
316 "BUILD_VECTOR operand type doesn't match vector element type!");
318 // Build a vector of twice the length out of the expanded elements.
319 // For example <3 x i64> -> <6 x i32>.
320 std::vector<SDValue> NewElts;
321 NewElts.reserve(NumElts*2);
323 for (unsigned i = 0; i < NumElts; ++i) {
325 GetExpandedOp(N->getOperand(i), Lo, Hi);
326 if (TLI.isBigEndian())
328 NewElts.push_back(Lo);
329 NewElts.push_back(Hi);
332 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
333 EVT::getVectorVT(*DAG.getContext(),
334 NewVT, NewElts.size()),
335 &NewElts[0], NewElts.size());
337 // Convert the new vector to the old vector type.
338 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
341 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
343 GetExpandedOp(N->getOperand(0), Lo, Hi);
344 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
347 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
348 // The vector type is legal but the element type needs expansion.
349 EVT VecVT = N->getValueType(0);
350 unsigned NumElts = VecVT.getVectorNumElements();
351 DebugLoc dl = N->getDebugLoc();
353 SDValue Val = N->getOperand(1);
354 EVT OldEVT = Val.getValueType();
355 EVT NewEVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldEVT);
357 assert(OldEVT == VecVT.getVectorElementType() &&
358 "Inserted element type doesn't match vector element type!");
360 // Bitconvert to a vector of twice the length with elements of the expanded
361 // type, insert the expanded vector elements, and then convert back.
362 EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewEVT, NumElts*2);
363 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
364 NewVecVT, N->getOperand(0));
367 GetExpandedOp(Val, Lo, Hi);
368 if (TLI.isBigEndian())
371 SDValue Idx = N->getOperand(2);
372 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
373 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
374 Idx = DAG.getNode(ISD::ADD, dl,
375 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1));
376 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
378 // Convert the new vector to the old vector type.
379 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
382 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
383 DebugLoc dl = N->getDebugLoc();
384 EVT VT = N->getValueType(0);
385 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
386 "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
387 unsigned NumElts = VT.getVectorNumElements();
388 SmallVector<SDValue, 16> Ops(NumElts);
389 Ops[0] = N->getOperand(0);
390 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
391 for (unsigned i = 1; i < NumElts; ++i)
393 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts);
396 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
397 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
398 assert(OpNo == 1 && "Can only expand the stored value so far");
399 DebugLoc dl = N->getDebugLoc();
401 StoreSDNode *St = cast<StoreSDNode>(N);
402 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(),
403 St->getValue().getValueType());
404 SDValue Chain = St->getChain();
405 SDValue Ptr = St->getBasePtr();
406 unsigned Alignment = St->getAlignment();
407 bool isVolatile = St->isVolatile();
408 bool isNonTemporal = St->isNonTemporal();
410 assert(NVT.isByteSized() && "Expanded type not byte sized!");
411 unsigned IncrementSize = NVT.getSizeInBits() / 8;
414 GetExpandedOp(St->getValue(), Lo, Hi);
416 if (TLI.isBigEndian())
419 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getPointerInfo(),
420 isVolatile, isNonTemporal, Alignment);
422 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
423 DAG.getIntPtrConstant(IncrementSize));
424 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!");
425 Hi = DAG.getStore(Chain, dl, Hi, Ptr,
426 St->getPointerInfo().getWithOffset(IncrementSize),
427 isVolatile, isNonTemporal,
428 MinAlign(Alignment, IncrementSize));
430 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
434 //===--------------------------------------------------------------------===//
435 // Generic Result Splitting.
436 //===--------------------------------------------------------------------===//
438 // Be careful to make no assumptions about which of Lo/Hi is stored first in
439 // memory (for vectors it is always Lo first followed by Hi in the following
440 // bytes; for integers and floats it is Lo first if and only if the machine is
443 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
444 SDValue &Lo, SDValue &Hi) {
445 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
446 GetSplitOp(Op, Lo, Hi);
449 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
451 SDValue LL, LH, RL, RH, CL, CH;
452 DebugLoc dl = N->getDebugLoc();
453 GetSplitOp(N->getOperand(1), LL, LH);
454 GetSplitOp(N->getOperand(2), RL, RH);
456 SDValue Cond = N->getOperand(0);
458 if (Cond.getValueType().isVector()) {
459 assert(Cond.getValueType().getVectorElementType() == MVT::i1 &&
460 "Condition legalized before result?");
461 unsigned NumElements = Cond.getValueType().getVectorNumElements();
462 EVT VCondTy = EVT::getVectorVT(*DAG.getContext(), MVT::i1, NumElements / 2);
463 CL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
464 DAG.getIntPtrConstant(0));
465 CH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
466 DAG.getIntPtrConstant(NumElements / 2));
469 Lo = DAG.getNode(N->getOpcode(), dl, LL.getValueType(), CL, LL, RL);
470 Hi = DAG.getNode(N->getOpcode(), dl, LH.getValueType(), CH, LH, RH);
473 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
475 SDValue LL, LH, RL, RH;
476 DebugLoc dl = N->getDebugLoc();
477 GetSplitOp(N->getOperand(2), LL, LH);
478 GetSplitOp(N->getOperand(3), RL, RH);
480 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
481 N->getOperand(1), LL, RL, N->getOperand(4));
482 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
483 N->getOperand(1), LH, RH, N->getOperand(4));
486 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
488 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
489 Lo = DAG.getUNDEF(LoVT);
490 Hi = DAG.getUNDEF(HiVT);