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)) {
49 assert(false && "Unknown type action!");
50 case TargetLowering::TypeLegal:
51 case TargetLowering::TypePromoteInteger:
53 case TargetLowering::TypeSoftenFloat:
54 // Convert the integer operand instead.
55 SplitInteger(GetSoftenedFloat(InOp), Lo, Hi);
56 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
57 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
59 case TargetLowering::TypeExpandInteger:
60 case TargetLowering::TypeExpandFloat:
61 // Convert the expanded pieces of the input.
62 GetExpandedOp(InOp, Lo, Hi);
63 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
64 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
66 case TargetLowering::TypeSplitVector:
67 GetSplitVector(InOp, Lo, Hi);
68 if (TLI.isBigEndian())
70 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
71 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
73 case TargetLowering::TypeScalarizeVector:
74 // Convert the element instead.
75 SplitInteger(BitConvertToInteger(GetScalarizedVector(InOp)), Lo, Hi);
76 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
77 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
79 case TargetLowering::TypeWidenVector: {
80 assert(!(InVT.getVectorNumElements() & 1) && "Unsupported BITCAST");
81 InOp = GetWidenedVector(InOp);
82 EVT InNVT = EVT::getVectorVT(*DAG.getContext(), InVT.getVectorElementType(),
83 InVT.getVectorNumElements()/2);
84 Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, InOp,
85 DAG.getIntPtrConstant(0));
86 Hi = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, InOp,
87 DAG.getIntPtrConstant(InNVT.getVectorNumElements()));
88 if (TLI.isBigEndian())
90 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
91 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
96 if (InVT.isVector() && OutVT.isInteger()) {
97 // Handle cases like i64 = BITCAST v1i64 on x86, where the operand
98 // is legal but the result is not.
99 EVT NVT = EVT::getVectorVT(*DAG.getContext(), NOutVT, 2);
101 if (isTypeLegal(NVT)) {
102 SDValue CastInOp = DAG.getNode(ISD::BITCAST, dl, NVT, InOp);
103 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp,
104 DAG.getIntPtrConstant(0));
105 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp,
106 DAG.getIntPtrConstant(1));
108 if (TLI.isBigEndian())
115 // Lower the bit-convert to a store/load from the stack.
116 assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
118 // Create the stack frame object. Make sure it is aligned for both
119 // the source and expanded destination types.
121 TLI.getTargetData()->getPrefTypeAlignment(NOutVT.
122 getTypeForEVT(*DAG.getContext()));
123 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment);
124 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
125 MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI);
127 // Emit a store to the stack slot.
128 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, PtrInfo,
131 // Load the first half from the stack slot.
132 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, PtrInfo,
133 false, false, false, 0);
135 // Increment the pointer to the other half.
136 unsigned IncrementSize = NOutVT.getSizeInBits() / 8;
137 StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
138 DAG.getIntPtrConstant(IncrementSize));
140 // Load the second half from the stack slot.
141 Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr,
142 PtrInfo.getWithOffset(IncrementSize), false,
143 false, false, MinAlign(Alignment, IncrementSize));
145 // Handle endianness of the load.
146 if (TLI.isBigEndian())
150 void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
152 // Return the operands.
153 Lo = N->getOperand(0);
154 Hi = N->getOperand(1);
157 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
159 GetExpandedOp(N->getOperand(0), Lo, Hi);
160 SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ?
163 assert(Part.getValueType() == N->getValueType(0) &&
164 "Type twice as big as expanded type not itself expanded!");
166 GetPairElements(Part, Lo, Hi);
169 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
171 SDValue OldVec = N->getOperand(0);
172 unsigned OldElts = OldVec.getValueType().getVectorNumElements();
173 DebugLoc dl = N->getDebugLoc();
175 // Convert to a vector of the expanded element type, for example
176 // <3 x i64> -> <6 x i32>.
177 EVT OldVT = N->getValueType(0);
178 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
180 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
181 EVT::getVectorVT(*DAG.getContext(),
185 // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector.
186 SDValue Idx = N->getOperand(1);
188 // Make sure the type of Idx is big enough to hold the new values.
189 if (Idx.getValueType().bitsLT(TLI.getPointerTy()))
190 Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
192 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
193 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
195 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
196 DAG.getConstant(1, Idx.getValueType()));
197 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
199 if (TLI.isBigEndian())
203 void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo,
205 assert(ISD::isNormalLoad(N) && "This routine only for normal loads!");
206 DebugLoc dl = N->getDebugLoc();
208 LoadSDNode *LD = cast<LoadSDNode>(N);
209 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), LD->getValueType(0));
210 SDValue Chain = LD->getChain();
211 SDValue Ptr = LD->getBasePtr();
212 unsigned Alignment = LD->getAlignment();
213 bool isVolatile = LD->isVolatile();
214 bool isNonTemporal = LD->isNonTemporal();
215 bool isInvariant = LD->isInvariant();
217 assert(NVT.isByteSized() && "Expanded type not byte sized!");
219 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getPointerInfo(),
220 isVolatile, isNonTemporal, isInvariant, Alignment);
222 // Increment the pointer to the other half.
223 unsigned IncrementSize = NVT.getSizeInBits() / 8;
224 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
225 DAG.getIntPtrConstant(IncrementSize));
226 Hi = DAG.getLoad(NVT, dl, Chain, Ptr,
227 LD->getPointerInfo().getWithOffset(IncrementSize),
228 isVolatile, isNonTemporal, isInvariant,
229 MinAlign(Alignment, IncrementSize));
231 // Build a factor node to remember that this load is independent of the
233 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
236 // Handle endianness of the load.
237 if (TLI.isBigEndian())
240 // Modified the chain - switch anything that used the old chain to use
242 ReplaceValueWith(SDValue(N, 1), Chain);
245 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
246 EVT OVT = N->getValueType(0);
247 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), OVT);
248 SDValue Chain = N->getOperand(0);
249 SDValue Ptr = N->getOperand(1);
250 DebugLoc dl = N->getDebugLoc();
251 const unsigned Align = N->getConstantOperandVal(3);
253 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2), Align);
254 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2), 0);
256 // Handle endianness of the load.
257 if (TLI.isBigEndian())
260 // Modified the chain - switch anything that used the old chain to use
262 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
266 //===--------------------------------------------------------------------===//
267 // Generic Operand Expansion.
268 //===--------------------------------------------------------------------===//
270 SDValue DAGTypeLegalizer::ExpandOp_BITCAST(SDNode *N) {
271 DebugLoc dl = N->getDebugLoc();
272 if (N->getValueType(0).isVector()) {
273 // An illegal expanding type is being converted to a legal vector type.
274 // Make a two element vector out of the expanded parts and convert that
275 // instead, but only if the new vector type is legal (otherwise there
276 // is no point, and it might create expansion loops). For example, on
277 // x86 this turns v1i64 = BITCAST i64 into v1i64 = BITCAST v2i32.
278 EVT OVT = N->getOperand(0).getValueType();
279 EVT NVT = EVT::getVectorVT(*DAG.getContext(),
280 TLI.getTypeToTransformTo(*DAG.getContext(), OVT),
283 if (isTypeLegal(NVT)) {
285 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]);
287 if (TLI.isBigEndian())
288 std::swap(Parts[0], Parts[1]);
290 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2);
291 return DAG.getNode(ISD::BITCAST, dl, N->getValueType(0), Vec);
295 // Otherwise, store to a temporary and load out again as the new type.
296 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
299 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
300 // The vector type is legal but the element type needs expansion.
301 EVT VecVT = N->getValueType(0);
302 unsigned NumElts = VecVT.getVectorNumElements();
303 EVT OldVT = N->getOperand(0).getValueType();
304 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
305 DebugLoc dl = N->getDebugLoc();
307 assert(OldVT == VecVT.getVectorElementType() &&
308 "BUILD_VECTOR operand type doesn't match vector element type!");
310 // Build a vector of twice the length out of the expanded elements.
311 // For example <3 x i64> -> <6 x i32>.
312 std::vector<SDValue> NewElts;
313 NewElts.reserve(NumElts*2);
315 for (unsigned i = 0; i < NumElts; ++i) {
317 GetExpandedOp(N->getOperand(i), Lo, Hi);
318 if (TLI.isBigEndian())
320 NewElts.push_back(Lo);
321 NewElts.push_back(Hi);
324 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
325 EVT::getVectorVT(*DAG.getContext(),
326 NewVT, NewElts.size()),
327 &NewElts[0], NewElts.size());
329 // Convert the new vector to the old vector type.
330 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
333 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
335 GetExpandedOp(N->getOperand(0), Lo, Hi);
336 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
339 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
340 // The vector type is legal but the element type needs expansion.
341 EVT VecVT = N->getValueType(0);
342 unsigned NumElts = VecVT.getVectorNumElements();
343 DebugLoc dl = N->getDebugLoc();
345 SDValue Val = N->getOperand(1);
346 EVT OldEVT = Val.getValueType();
347 EVT NewEVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldEVT);
349 assert(OldEVT == VecVT.getVectorElementType() &&
350 "Inserted element type doesn't match vector element type!");
352 // Bitconvert to a vector of twice the length with elements of the expanded
353 // type, insert the expanded vector elements, and then convert back.
354 EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewEVT, NumElts*2);
355 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
356 NewVecVT, N->getOperand(0));
359 GetExpandedOp(Val, Lo, Hi);
360 if (TLI.isBigEndian())
363 SDValue Idx = N->getOperand(2);
364 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
365 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
366 Idx = DAG.getNode(ISD::ADD, dl,
367 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1));
368 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
370 // Convert the new vector to the old vector type.
371 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
374 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
375 DebugLoc dl = N->getDebugLoc();
376 EVT VT = N->getValueType(0);
377 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
378 "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
379 unsigned NumElts = VT.getVectorNumElements();
380 SmallVector<SDValue, 16> Ops(NumElts);
381 Ops[0] = N->getOperand(0);
382 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
383 for (unsigned i = 1; i < NumElts; ++i)
385 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts);
388 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
389 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
390 assert(OpNo == 1 && "Can only expand the stored value so far");
391 DebugLoc dl = N->getDebugLoc();
393 StoreSDNode *St = cast<StoreSDNode>(N);
394 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(),
395 St->getValue().getValueType());
396 SDValue Chain = St->getChain();
397 SDValue Ptr = St->getBasePtr();
398 unsigned Alignment = St->getAlignment();
399 bool isVolatile = St->isVolatile();
400 bool isNonTemporal = St->isNonTemporal();
402 assert(NVT.isByteSized() && "Expanded type not byte sized!");
403 unsigned IncrementSize = NVT.getSizeInBits() / 8;
406 GetExpandedOp(St->getValue(), Lo, Hi);
408 if (TLI.isBigEndian())
411 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getPointerInfo(),
412 isVolatile, isNonTemporal, Alignment);
414 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
415 DAG.getIntPtrConstant(IncrementSize));
416 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!");
417 Hi = DAG.getStore(Chain, dl, Hi, Ptr,
418 St->getPointerInfo().getWithOffset(IncrementSize),
419 isVolatile, isNonTemporal,
420 MinAlign(Alignment, IncrementSize));
422 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
426 //===--------------------------------------------------------------------===//
427 // Generic Result Splitting.
428 //===--------------------------------------------------------------------===//
430 // Be careful to make no assumptions about which of Lo/Hi is stored first in
431 // memory (for vectors it is always Lo first followed by Hi in the following
432 // bytes; for integers and floats it is Lo first if and only if the machine is
435 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
436 SDValue &Lo, SDValue &Hi) {
437 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
438 GetSplitOp(Op, Lo, Hi);
441 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
443 SDValue LL, LH, RL, RH, CL, CH;
444 DebugLoc dl = N->getDebugLoc();
445 GetSplitOp(N->getOperand(1), LL, LH);
446 GetSplitOp(N->getOperand(2), RL, RH);
448 SDValue Cond = N->getOperand(0);
450 if (Cond.getValueType().isVector()) {
451 assert(Cond.getValueType().getVectorElementType() == MVT::i1 &&
452 "Condition legalized before result?");
453 unsigned NumElements = Cond.getValueType().getVectorNumElements();
454 EVT VCondTy = EVT::getVectorVT(*DAG.getContext(), MVT::i1, NumElements / 2);
455 CL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
456 DAG.getIntPtrConstant(0));
457 CH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
458 DAG.getIntPtrConstant(NumElements / 2));
461 Lo = DAG.getNode(N->getOpcode(), dl, LL.getValueType(), CL, LL, RL);
462 Hi = DAG.getNode(N->getOpcode(), dl, LH.getValueType(), CH, LH, RH);
465 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
467 SDValue LL, LH, RL, RH;
468 DebugLoc dl = N->getDebugLoc();
469 GetSplitOp(N->getOperand(2), LL, LH);
470 GetSplitOp(N->getOperand(3), RL, RH);
472 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
473 N->getOperand(1), LL, RL, N->getOperand(4));
474 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
475 N->getOperand(1), LH, RH, N->getOperand(4));
478 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
480 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
481 Lo = DAG.getUNDEF(LoVT);
482 Hi = DAG.getUNDEF(HiVT);