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.
35 void DAGTypeLegalizer::ExpandRes_BIT_CONVERT(SDNode *N, SDValue &Lo,
37 EVT OutVT = N->getValueType(0);
38 EVT NOutVT = TLI.getTypeToTransformTo(*DAG.getContext(), OutVT);
39 SDValue InOp = N->getOperand(0);
40 EVT InVT = InOp.getValueType();
41 DebugLoc dl = N->getDebugLoc();
43 // Handle some special cases efficiently.
44 switch (getTypeAction(InVT)) {
46 assert(false && "Unknown type action!");
51 // Convert the integer operand instead.
52 SplitInteger(GetSoftenedFloat(InOp), Lo, Hi);
53 Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
54 Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
58 // Convert the expanded pieces of the input.
59 GetExpandedOp(InOp, Lo, Hi);
60 Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
61 Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
64 GetSplitVector(InOp, Lo, Hi);
65 if (TLI.isBigEndian())
67 Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
68 Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
71 // Convert the element instead.
72 SplitInteger(BitConvertToInteger(GetScalarizedVector(InOp)), Lo, Hi);
73 Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
74 Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
77 assert(!(InVT.getVectorNumElements() & 1) && "Unsupported BIT_CONVERT");
78 InOp = GetWidenedVector(InOp);
79 EVT InNVT = EVT::getVectorVT(*DAG.getContext(), InVT.getVectorElementType(),
80 InVT.getVectorNumElements()/2);
81 Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, InOp,
82 DAG.getIntPtrConstant(0));
83 Hi = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, InOp,
84 DAG.getIntPtrConstant(InNVT.getVectorNumElements()));
85 if (TLI.isBigEndian())
87 Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
88 Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
93 if (InVT.isVector() && OutVT.isInteger()) {
94 // Handle cases like i64 = BIT_CONVERT v1i64 on x86, where the operand
95 // is legal but the result is not.
96 EVT NVT = EVT::getVectorVT(*DAG.getContext(), NOutVT, 2);
98 if (isTypeLegal(NVT)) {
99 SDValue CastInOp = DAG.getNode(ISD::BIT_CONVERT, dl, NVT, InOp);
100 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp,
101 DAG.getIntPtrConstant(0));
102 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp,
103 DAG.getIntPtrConstant(1));
105 if (TLI.isBigEndian())
112 // Lower the bit-convert to a store/load from the stack.
113 assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
115 // Create the stack frame object. Make sure it is aligned for both
116 // the source and expanded destination types.
118 TLI.getTargetData()->getPrefTypeAlignment(NOutVT.
119 getTypeForEVT(*DAG.getContext()));
120 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment);
121 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
122 const Value *SV = PseudoSourceValue::getFixedStack(SPFI);
124 // Emit a store to the stack slot.
125 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, SV, 0,
128 // Load the first half from the stack slot.
129 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, SV, 0, false, false, 0);
131 // Increment the pointer to the other half.
132 unsigned IncrementSize = NOutVT.getSizeInBits() / 8;
133 StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
134 DAG.getIntPtrConstant(IncrementSize));
136 // Load the second half from the stack slot.
137 Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr, SV, IncrementSize, false,
138 false, MinAlign(Alignment, IncrementSize));
140 // Handle endianness of the load.
141 if (TLI.isBigEndian())
145 void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
147 // Return the operands.
148 Lo = N->getOperand(0);
149 Hi = N->getOperand(1);
152 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
154 GetExpandedOp(N->getOperand(0), Lo, Hi);
155 SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ?
158 assert(Part.getValueType() == N->getValueType(0) &&
159 "Type twice as big as expanded type not itself expanded!");
161 GetPairElements(Part, Lo, Hi);
164 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
166 SDValue OldVec = N->getOperand(0);
167 unsigned OldElts = OldVec.getValueType().getVectorNumElements();
168 DebugLoc dl = N->getDebugLoc();
170 // Convert to a vector of the expanded element type, for example
171 // <3 x i64> -> <6 x i32>.
172 EVT OldVT = N->getValueType(0);
173 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
175 SDValue NewVec = DAG.getNode(ISD::BIT_CONVERT, dl,
176 EVT::getVectorVT(*DAG.getContext(), NewVT, 2*OldElts),
179 // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector.
180 SDValue Idx = N->getOperand(1);
182 // Make sure the type of Idx is big enough to hold the new values.
183 if (Idx.getValueType().bitsLT(TLI.getPointerTy()))
184 Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
186 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
187 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
189 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
190 DAG.getConstant(1, Idx.getValueType()));
191 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
193 if (TLI.isBigEndian())
197 void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo,
199 assert(ISD::isNormalLoad(N) && "This routine only for normal loads!");
200 DebugLoc dl = N->getDebugLoc();
202 LoadSDNode *LD = cast<LoadSDNode>(N);
203 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), LD->getValueType(0));
204 SDValue Chain = LD->getChain();
205 SDValue Ptr = LD->getBasePtr();
206 int SVOffset = LD->getSrcValueOffset();
207 unsigned Alignment = LD->getAlignment();
208 bool isVolatile = LD->isVolatile();
209 bool isNonTemporal = LD->isNonTemporal();
211 assert(NVT.isByteSized() && "Expanded type not byte sized!");
213 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getSrcValue(), SVOffset,
214 isVolatile, isNonTemporal, Alignment);
216 // Increment the pointer to the other half.
217 unsigned IncrementSize = NVT.getSizeInBits() / 8;
218 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
219 DAG.getIntPtrConstant(IncrementSize));
220 Hi = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getSrcValue(),
221 SVOffset+IncrementSize,
222 isVolatile, isNonTemporal,
223 MinAlign(Alignment, IncrementSize));
225 // Build a factor node to remember that this load is independent of the
227 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
230 // Handle endianness of the load.
231 if (TLI.isBigEndian())
234 // Modified the chain - switch anything that used the old chain to use
236 ReplaceValueWith(SDValue(N, 1), Chain);
239 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
240 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), N->getValueType(0));
241 SDValue Chain = N->getOperand(0);
242 SDValue Ptr = N->getOperand(1);
243 DebugLoc dl = N->getDebugLoc();
245 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2));
246 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2));
248 // Handle endianness of the load.
249 if (TLI.isBigEndian())
252 // Modified the chain - switch anything that used the old chain to use
254 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
258 //===--------------------------------------------------------------------===//
259 // Generic Operand Expansion.
260 //===--------------------------------------------------------------------===//
262 SDValue DAGTypeLegalizer::ExpandOp_BIT_CONVERT(SDNode *N) {
263 DebugLoc dl = N->getDebugLoc();
264 if (N->getValueType(0).isVector()) {
265 // An illegal expanding type is being converted to a legal vector type.
266 // Make a two element vector out of the expanded parts and convert that
267 // instead, but only if the new vector type is legal (otherwise there
268 // is no point, and it might create expansion loops). For example, on
269 // x86 this turns v1i64 = BIT_CONVERT i64 into v1i64 = BIT_CONVERT v2i32.
270 EVT OVT = N->getOperand(0).getValueType();
271 EVT NVT = EVT::getVectorVT(*DAG.getContext(), TLI.getTypeToTransformTo(*DAG.getContext(), OVT), 2);
273 if (isTypeLegal(NVT)) {
275 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]);
277 if (TLI.isBigEndian())
278 std::swap(Parts[0], Parts[1]);
280 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2);
281 return DAG.getNode(ISD::BIT_CONVERT, dl, N->getValueType(0), Vec);
285 // Otherwise, store to a temporary and load out again as the new type.
286 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
289 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
290 // The vector type is legal but the element type needs expansion.
291 EVT VecVT = N->getValueType(0);
292 unsigned NumElts = VecVT.getVectorNumElements();
293 EVT OldVT = N->getOperand(0).getValueType();
294 EVT NewVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldVT);
295 DebugLoc dl = N->getDebugLoc();
297 assert(OldVT == VecVT.getVectorElementType() &&
298 "BUILD_VECTOR operand type doesn't match vector element type!");
300 // Build a vector of twice the length out of the expanded elements.
301 // For example <3 x i64> -> <6 x i32>.
302 std::vector<SDValue> NewElts;
303 NewElts.reserve(NumElts*2);
305 for (unsigned i = 0; i < NumElts; ++i) {
307 GetExpandedOp(N->getOperand(i), Lo, Hi);
308 if (TLI.isBigEndian())
310 NewElts.push_back(Lo);
311 NewElts.push_back(Hi);
314 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
315 EVT::getVectorVT(*DAG.getContext(), NewVT, NewElts.size()),
316 &NewElts[0], NewElts.size());
318 // Convert the new vector to the old vector type.
319 return DAG.getNode(ISD::BIT_CONVERT, dl, VecVT, NewVec);
322 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
324 GetExpandedOp(N->getOperand(0), Lo, Hi);
325 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
328 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
329 // The vector type is legal but the element type needs expansion.
330 EVT VecVT = N->getValueType(0);
331 unsigned NumElts = VecVT.getVectorNumElements();
332 DebugLoc dl = N->getDebugLoc();
334 SDValue Val = N->getOperand(1);
335 EVT OldEVT = Val.getValueType();
336 EVT NewEVT = TLI.getTypeToTransformTo(*DAG.getContext(), OldEVT);
338 assert(OldEVT == VecVT.getVectorElementType() &&
339 "Inserted element type doesn't match vector element type!");
341 // Bitconvert to a vector of twice the length with elements of the expanded
342 // type, insert the expanded vector elements, and then convert back.
343 EVT NewVecVT = EVT::getVectorVT(*DAG.getContext(), NewEVT, NumElts*2);
344 SDValue NewVec = DAG.getNode(ISD::BIT_CONVERT, dl,
345 NewVecVT, N->getOperand(0));
348 GetExpandedOp(Val, Lo, Hi);
349 if (TLI.isBigEndian())
352 SDValue Idx = N->getOperand(2);
353 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
354 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
355 Idx = DAG.getNode(ISD::ADD, dl,
356 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1));
357 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
359 // Convert the new vector to the old vector type.
360 return DAG.getNode(ISD::BIT_CONVERT, dl, VecVT, NewVec);
363 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
364 DebugLoc dl = N->getDebugLoc();
365 EVT VT = N->getValueType(0);
366 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
367 "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
368 unsigned NumElts = VT.getVectorNumElements();
369 SmallVector<SDValue, 16> Ops(NumElts);
370 Ops[0] = N->getOperand(0);
371 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
372 for (unsigned i = 1; i < NumElts; ++i)
374 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts);
377 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
378 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
379 assert(OpNo == 1 && "Can only expand the stored value so far");
380 DebugLoc dl = N->getDebugLoc();
382 StoreSDNode *St = cast<StoreSDNode>(N);
383 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), St->getValue().getValueType());
384 SDValue Chain = St->getChain();
385 SDValue Ptr = St->getBasePtr();
386 int SVOffset = St->getSrcValueOffset();
387 unsigned Alignment = St->getAlignment();
388 bool isVolatile = St->isVolatile();
389 bool isNonTemporal = St->isNonTemporal();
391 assert(NVT.isByteSized() && "Expanded type not byte sized!");
392 unsigned IncrementSize = NVT.getSizeInBits() / 8;
395 GetExpandedOp(St->getValue(), Lo, Hi);
397 if (TLI.isBigEndian())
400 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getSrcValue(), SVOffset,
401 isVolatile, isNonTemporal, Alignment);
403 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
404 DAG.getIntPtrConstant(IncrementSize));
405 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!");
406 Hi = DAG.getStore(Chain, dl, Hi, Ptr, St->getSrcValue(),
407 SVOffset + IncrementSize,
408 isVolatile, isNonTemporal,
409 MinAlign(Alignment, IncrementSize));
411 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
415 //===--------------------------------------------------------------------===//
416 // Generic Result Splitting.
417 //===--------------------------------------------------------------------===//
419 // Be careful to make no assumptions about which of Lo/Hi is stored first in
420 // memory (for vectors it is always Lo first followed by Hi in the following
421 // bytes; for integers and floats it is Lo first if and only if the machine is
424 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N,
425 SDValue &Lo, SDValue &Hi) {
426 // A MERGE_VALUES node can produce any number of values. We know that the
427 // first illegal one needs to be expanded into Lo/Hi.
430 // The string of legal results gets turned into input operands, which have
432 for (i = 0; isTypeLegal(N->getValueType(i)); ++i)
433 ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i)));
435 // The first illegal result must be the one that needs to be expanded.
436 GetSplitOp(N->getOperand(i), Lo, Hi);
438 // Legalize the rest of the results into the input operands whether they are
440 unsigned e = N->getNumValues();
441 for (++i; i != e; ++i)
442 ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i)));
445 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
447 SDValue LL, LH, RL, RH;
448 DebugLoc dl = N->getDebugLoc();
449 GetSplitOp(N->getOperand(1), LL, LH);
450 GetSplitOp(N->getOperand(2), RL, RH);
452 SDValue Cond = N->getOperand(0);
453 Lo = DAG.getNode(ISD::SELECT, dl, LL.getValueType(), Cond, LL, RL);
454 Hi = DAG.getNode(ISD::SELECT, dl, LH.getValueType(), Cond, LH, RH);
457 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
459 SDValue LL, LH, RL, RH;
460 DebugLoc dl = N->getDebugLoc();
461 GetSplitOp(N->getOperand(2), LL, LH);
462 GetSplitOp(N->getOperand(3), RL, RH);
464 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
465 N->getOperand(1), LL, RL, N->getOperand(4));
466 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
467 N->getOperand(1), LH, RH, N->getOperand(4));
470 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
472 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
473 Lo = DAG.getUNDEF(LoVT);
474 Hi = DAG.getUNDEF(HiVT);