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"
24 #include "llvm/CodeGen/PseudoSourceValue.h"
27 //===----------------------------------------------------------------------===//
28 // Generic Result Expansion.
29 //===----------------------------------------------------------------------===//
31 // These routines assume that the Lo/Hi part is stored first in memory on
32 // little/big-endian machines, followed by the Hi/Lo part. This means that
33 // they cannot be used as is on vectors, for which Lo is always stored first.
34 void DAGTypeLegalizer::ExpandRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
35 SDValue &Lo, SDValue &Hi) {
36 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
37 GetExpandedOp(Op, Lo, Hi);
40 void DAGTypeLegalizer::ExpandRes_BITCAST(SDNode *N, SDValue &Lo, SDValue &Hi) {
41 EVT OutVT = N->getValueType(0);
42 EVT NOutVT = TLI.getTypeToTransformTo(*DAG.getContext(), OutVT);
43 SDValue InOp = N->getOperand(0);
44 EVT InVT = InOp.getValueType();
45 DebugLoc dl = N->getDebugLoc();
47 // Handle some special cases efficiently.
48 switch (getTypeAction(InVT)) {
50 assert(false && "Unknown type action!");
51 case TargetLowering::TypeLegal:
52 case TargetLowering::TypePromoteInteger:
54 case TargetLowering::TypeSoftenFloat:
55 // Convert the integer operand instead.
56 SplitInteger(GetSoftenedFloat(InOp), Lo, Hi);
57 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
58 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
60 case TargetLowering::TypeExpandInteger:
61 case TargetLowering::TypeExpandFloat:
62 // Convert the expanded pieces of the input.
63 GetExpandedOp(InOp, Lo, Hi);
64 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
65 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
67 case TargetLowering::TypeSplitVector:
68 GetSplitVector(InOp, Lo, Hi);
69 if (TLI.isBigEndian())
71 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
72 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
74 case TargetLowering::TypeScalarizeVector:
75 // Convert the element instead.
76 SplitInteger(BitConvertToInteger(GetScalarizedVector(InOp)), Lo, Hi);
77 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
78 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
80 case TargetLowering::TypeWidenVector: {
81 assert(!(InVT.getVectorNumElements() & 1) && "Unsupported BITCAST");
82 InOp = GetWidenedVector(InOp);
83 EVT InNVT = EVT::getVectorVT(*DAG.getContext(), InVT.getVectorElementType(),
84 InVT.getVectorNumElements()/2);
85 Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, InOp,
86 DAG.getIntPtrConstant(0));
87 Hi = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, InOp,
88 DAG.getIntPtrConstant(InNVT.getVectorNumElements()));
89 if (TLI.isBigEndian())
91 Lo = DAG.getNode(ISD::BITCAST, dl, NOutVT, Lo);
92 Hi = DAG.getNode(ISD::BITCAST, dl, NOutVT, Hi);
97 if (InVT.isVector() && OutVT.isInteger()) {
98 // Handle cases like i64 = BITCAST v1i64 on x86, where the operand
99 // is legal but the result is not.
100 EVT NVT = EVT::getVectorVT(*DAG.getContext(), NOutVT, 2);
102 if (isTypeLegal(NVT)) {
103 SDValue CastInOp = DAG.getNode(ISD::BITCAST, dl, NVT, InOp);
104 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp,
105 DAG.getIntPtrConstant(0));
106 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp,
107 DAG.getIntPtrConstant(1));
109 if (TLI.isBigEndian())
116 // Lower the bit-convert to a store/load from the stack.
117 assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
119 // Create the stack frame object. Make sure it is aligned for both
120 // the source and expanded destination types.
122 TLI.getTargetData()->getPrefTypeAlignment(NOutVT.
123 getTypeForEVT(*DAG.getContext()));
124 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment);
125 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
126 MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI);
128 // Emit a store to the stack slot.
129 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, PtrInfo,
132 // Load the first half from the stack slot.
133 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, PtrInfo, 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, 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();
216 assert(NVT.isByteSized() && "Expanded type not byte sized!");
218 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getPointerInfo(),
219 isVolatile, isNonTemporal, Alignment);
221 // Increment the pointer to the other half.
222 unsigned IncrementSize = NVT.getSizeInBits() / 8;
223 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
224 DAG.getIntPtrConstant(IncrementSize));
225 Hi = DAG.getLoad(NVT, dl, Chain, Ptr,
226 LD->getPointerInfo().getWithOffset(IncrementSize),
227 isVolatile, isNonTemporal,
228 MinAlign(Alignment, IncrementSize));
230 // Build a factor node to remember that this load is independent of the
232 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
235 // Handle endianness of the load.
236 if (TLI.isBigEndian())
239 // Modified the chain - switch anything that used the old chain to use
241 ReplaceValueWith(SDValue(N, 1), Chain);
244 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
245 EVT OVT = N->getValueType(0);
246 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), OVT);
247 SDValue Chain = N->getOperand(0);
248 SDValue Ptr = N->getOperand(1);
249 DebugLoc dl = N->getDebugLoc();
250 const unsigned Align = N->getConstantOperandVal(3);
252 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2), Align);
253 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2), 0);
255 // Handle endianness of the load.
256 if (TLI.isBigEndian())
259 // Modified the chain - switch anything that used the old chain to use
261 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
265 //===--------------------------------------------------------------------===//
266 // Generic Operand Expansion.
267 //===--------------------------------------------------------------------===//
269 SDValue DAGTypeLegalizer::ExpandOp_BITCAST(SDNode *N) {
270 DebugLoc dl = N->getDebugLoc();
271 if (N->getValueType(0).isVector()) {
272 // An illegal expanding type is being converted to a legal vector type.
273 // Make a two element vector out of the expanded parts and convert that
274 // instead, but only if the new vector type is legal (otherwise there
275 // is no point, and it might create expansion loops). For example, on
276 // x86 this turns v1i64 = BITCAST i64 into v1i64 = BITCAST v2i32.
277 EVT OVT = N->getOperand(0).getValueType();
278 EVT NVT = EVT::getVectorVT(*DAG.getContext(),
279 TLI.getTypeToTransformTo(*DAG.getContext(), OVT),
282 if (isTypeLegal(NVT)) {
284 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]);
286 if (TLI.isBigEndian())
287 std::swap(Parts[0], Parts[1]);
289 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2);
290 return DAG.getNode(ISD::BITCAST, dl, N->getValueType(0), Vec);
294 // Otherwise, store to a temporary and load out again as the new type.
295 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
298 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
299 // The vector type is legal but the element type needs expansion.
300 EVT VecVT = N->getValueType(0);
301 unsigned NumElts = VecVT.getVectorNumElements();
302 EVT OldVT = N->getOperand(0).getValueType();
303 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
304 DebugLoc dl = N->getDebugLoc();
306 assert(OldVT == VecVT.getVectorElementType() &&
307 "BUILD_VECTOR operand type doesn't match vector element type!");
309 // Build a vector of twice the length out of the expanded elements.
310 // For example <3 x i64> -> <6 x i32>.
311 std::vector<SDValue> NewElts;
312 NewElts.reserve(NumElts*2);
314 for (unsigned i = 0; i < NumElts; ++i) {
316 GetExpandedOp(N->getOperand(i), Lo, Hi);
317 if (TLI.isBigEndian())
319 NewElts.push_back(Lo);
320 NewElts.push_back(Hi);
323 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
324 EVT::getVectorVT(*DAG.getContext(),
325 NewVT, NewElts.size()),
326 &NewElts[0], NewElts.size());
328 // Convert the new vector to the old vector type.
329 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
332 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
334 GetExpandedOp(N->getOperand(0), Lo, Hi);
335 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
338 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
339 // The vector type is legal but the element type needs expansion.
340 EVT VecVT = N->getValueType(0);
341 unsigned NumElts = VecVT.getVectorNumElements();
342 DebugLoc dl = N->getDebugLoc();
344 SDValue Val = N->getOperand(1);
345 EVT OldEVT = Val.getValueType();
346 EVT NewEVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldEVT);
348 assert(OldEVT == VecVT.getVectorElementType() &&
349 "Inserted element type doesn't match vector element type!");
351 // Bitconvert to a vector of twice the length with elements of the expanded
352 // type, insert the expanded vector elements, and then convert back.
353 EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewEVT, NumElts*2);
354 SDValue NewVec = DAG.getNode(ISD::BITCAST, dl,
355 NewVecVT, N->getOperand(0));
358 GetExpandedOp(Val, Lo, Hi);
359 if (TLI.isBigEndian())
362 SDValue Idx = N->getOperand(2);
363 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
364 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
365 Idx = DAG.getNode(ISD::ADD, dl,
366 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1));
367 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
369 // Convert the new vector to the old vector type.
370 return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
373 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
374 DebugLoc dl = N->getDebugLoc();
375 EVT VT = N->getValueType(0);
376 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
377 "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
378 unsigned NumElts = VT.getVectorNumElements();
379 SmallVector<SDValue, 16> Ops(NumElts);
380 Ops[0] = N->getOperand(0);
381 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
382 for (unsigned i = 1; i < NumElts; ++i)
384 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts);
387 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
388 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
389 assert(OpNo == 1 && "Can only expand the stored value so far");
390 DebugLoc dl = N->getDebugLoc();
392 StoreSDNode *St = cast<StoreSDNode>(N);
393 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(),
394 St->getValue().getValueType());
395 SDValue Chain = St->getChain();
396 SDValue Ptr = St->getBasePtr();
397 unsigned Alignment = St->getAlignment();
398 bool isVolatile = St->isVolatile();
399 bool isNonTemporal = St->isNonTemporal();
401 assert(NVT.isByteSized() && "Expanded type not byte sized!");
402 unsigned IncrementSize = NVT.getSizeInBits() / 8;
405 GetExpandedOp(St->getValue(), Lo, Hi);
407 if (TLI.isBigEndian())
410 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getPointerInfo(),
411 isVolatile, isNonTemporal, Alignment);
413 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
414 DAG.getIntPtrConstant(IncrementSize));
415 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!");
416 Hi = DAG.getStore(Chain, dl, Hi, Ptr,
417 St->getPointerInfo().getWithOffset(IncrementSize),
418 isVolatile, isNonTemporal,
419 MinAlign(Alignment, IncrementSize));
421 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
425 //===--------------------------------------------------------------------===//
426 // Generic Result Splitting.
427 //===--------------------------------------------------------------------===//
429 // Be careful to make no assumptions about which of Lo/Hi is stored first in
430 // memory (for vectors it is always Lo first followed by Hi in the following
431 // bytes; for integers and floats it is Lo first if and only if the machine is
434 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N, unsigned ResNo,
435 SDValue &Lo, SDValue &Hi) {
436 SDValue Op = DisintegrateMERGE_VALUES(N, ResNo);
437 GetSplitOp(Op, Lo, Hi);
440 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
442 SDValue LL, LH, RL, RH, CL, CH;
443 DebugLoc dl = N->getDebugLoc();
444 GetSplitOp(N->getOperand(1), LL, LH);
445 GetSplitOp(N->getOperand(2), RL, RH);
447 SDValue Cond = N->getOperand(0);
449 if (Cond.getValueType().isVector()) {
450 assert(Cond.getValueType().getVectorElementType() == MVT::i1 &&
451 "Condition legalized before result?");
452 unsigned NumElements = Cond.getValueType().getVectorNumElements();
453 EVT VCondTy = EVT::getVectorVT(*DAG.getContext(), MVT::i1, NumElements / 2);
454 CL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
455 DAG.getIntPtrConstant(0));
456 CH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, VCondTy, Cond,
457 DAG.getIntPtrConstant(NumElements / 2));
460 Lo = DAG.getNode(N->getOpcode(), dl, LL.getValueType(), CL, LL, RL);
461 Hi = DAG.getNode(N->getOpcode(), dl, LH.getValueType(), CH, LH, RH);
464 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
466 SDValue LL, LH, RL, RH;
467 DebugLoc dl = N->getDebugLoc();
468 GetSplitOp(N->getOperand(2), LL, LH);
469 GetSplitOp(N->getOperand(3), RL, RH);
471 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
472 N->getOperand(1), LL, RL, N->getOperand(4));
473 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
474 N->getOperand(1), LH, RH, N->getOperand(4));
477 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
479 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
480 Lo = DAG.getUNDEF(LoVT);
481 Hi = DAG.getUNDEF(HiVT);