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.
15 // Splitting is the act of changing a computation in an illegal type to be a
16 // computation in two not necessarily identical registers of a smaller type.
18 //===----------------------------------------------------------------------===//
20 #include "LegalizeTypes.h"
21 #include "llvm/Target/TargetData.h"
22 #include "llvm/CodeGen/PseudoSourceValue.h"
25 //===----------------------------------------------------------------------===//
26 // Generic Result Expansion.
27 //===----------------------------------------------------------------------===//
29 // These routines assume that the Lo/Hi part is stored first in memory on
30 // little/big-endian machines, followed by the Hi/Lo part. This means that
31 // they cannot be used as is on vectors, for which Lo is always stored first.
33 void DAGTypeLegalizer::ExpandRes_BIT_CONVERT(SDNode *N, SDValue &Lo,
35 MVT OutVT = N->getValueType(0);
36 MVT NOutVT = TLI.getTypeToTransformTo(OutVT);
37 SDValue InOp = N->getOperand(0);
38 MVT InVT = InOp.getValueType();
39 DebugLoc dl = N->getDebugLoc();
41 // Handle some special cases efficiently.
42 switch (getTypeAction(InVT)) {
44 assert(false && "Unknown type action!");
49 // Convert the integer operand instead.
50 SplitInteger(GetSoftenedFloat(InOp), Lo, Hi);
51 Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
52 Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
56 // Convert the expanded pieces of the input.
57 GetExpandedOp(InOp, Lo, Hi);
58 Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
59 Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
62 // Convert the split parts of the input if it was split in two.
63 GetSplitVector(InOp, Lo, Hi);
64 if (Lo.getValueType() == Hi.getValueType()) {
65 if (TLI.isBigEndian())
67 Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
68 Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
73 // Convert the element instead.
74 SplitInteger(BitConvertToInteger(GetScalarizedVector(InOp)), Lo, Hi);
75 Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
76 Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
79 assert(!(InVT.getVectorNumElements() & 1) && "Unsupported BIT_CONVERT");
80 InOp = GetWidenedVector(InOp);
81 MVT InNVT = MVT::getVectorVT(InVT.getVectorElementType(),
82 InVT.getVectorNumElements()/2);
83 Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, InOp,
84 DAG.getIntPtrConstant(0));
85 Hi = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, InOp,
86 DAG.getIntPtrConstant(InNVT.getVectorNumElements()));
87 if (TLI.isBigEndian())
89 Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
90 Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
95 // Lower the bit-convert to a store/load from the stack.
96 assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
98 // Create the stack frame object. Make sure it is aligned for both
99 // the source and expanded destination types.
101 TLI.getTargetData()->getPrefTypeAlignment(NOutVT.getTypeForMVT());
102 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment);
103 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
104 const Value *SV = PseudoSourceValue::getFixedStack(SPFI);
106 // Emit a store to the stack slot.
107 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, InOp, StackPtr, SV, 0);
109 // Load the first half from the stack slot.
110 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, SV, 0);
112 // Increment the pointer to the other half.
113 unsigned IncrementSize = NOutVT.getSizeInBits() / 8;
114 StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
115 DAG.getIntPtrConstant(IncrementSize));
117 // Load the second half from the stack slot.
118 Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr, SV, IncrementSize, false,
119 MinAlign(Alignment, IncrementSize));
121 // Handle endianness of the load.
122 if (TLI.isBigEndian())
126 void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
128 // Return the operands.
129 Lo = N->getOperand(0);
130 Hi = N->getOperand(1);
133 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
135 GetExpandedOp(N->getOperand(0), Lo, Hi);
136 SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ?
138 DebugLoc dl = N->getDebugLoc();
140 assert(Part.getValueType() == N->getValueType(0) &&
141 "Type twice as big as expanded type not itself expanded!");
142 MVT NVT = TLI.getTypeToTransformTo(N->getValueType(0));
144 Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, NVT, Part,
145 DAG.getConstant(0, TLI.getPointerTy()));
146 Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, NVT, Part,
147 DAG.getConstant(1, TLI.getPointerTy()));
150 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
152 SDValue OldVec = N->getOperand(0);
153 unsigned OldElts = OldVec.getValueType().getVectorNumElements();
154 DebugLoc dl = N->getDebugLoc();
156 // Convert to a vector of the expanded element type, for example
157 // <3 x i64> -> <6 x i32>.
158 MVT OldVT = N->getValueType(0);
159 MVT NewVT = TLI.getTypeToTransformTo(OldVT);
161 SDValue NewVec = DAG.getNode(ISD::BIT_CONVERT, dl,
162 MVT::getVectorVT(NewVT, 2*OldElts),
165 // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector.
166 SDValue Idx = N->getOperand(1);
168 // Make sure the type of Idx is big enough to hold the new values.
169 if (Idx.getValueType().bitsLT(TLI.getPointerTy()))
170 Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
172 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
173 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
175 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
176 DAG.getConstant(1, Idx.getValueType()));
177 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
179 if (TLI.isBigEndian())
183 void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo,
185 assert(ISD::isNormalLoad(N) && "This routine only for normal loads!");
186 DebugLoc dl = N->getDebugLoc();
188 LoadSDNode *LD = cast<LoadSDNode>(N);
189 MVT NVT = TLI.getTypeToTransformTo(LD->getValueType(0));
190 SDValue Chain = LD->getChain();
191 SDValue Ptr = LD->getBasePtr();
192 int SVOffset = LD->getSrcValueOffset();
193 unsigned Alignment = LD->getAlignment();
194 bool isVolatile = LD->isVolatile();
196 assert(NVT.isByteSized() && "Expanded type not byte sized!");
198 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getSrcValue(), SVOffset,
199 isVolatile, Alignment);
201 // Increment the pointer to the other half.
202 unsigned IncrementSize = NVT.getSizeInBits() / 8;
203 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
204 DAG.getIntPtrConstant(IncrementSize));
205 Hi = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getSrcValue(),
206 SVOffset+IncrementSize,
207 isVolatile, MinAlign(Alignment, IncrementSize));
209 // Build a factor node to remember that this load is independent of the
211 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
214 // Handle endianness of the load.
215 if (TLI.isBigEndian())
218 // Modified the chain - switch anything that used the old chain to use
220 ReplaceValueWith(SDValue(N, 1), Chain);
223 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
224 MVT NVT = TLI.getTypeToTransformTo(N->getValueType(0));
225 SDValue Chain = N->getOperand(0);
226 SDValue Ptr = N->getOperand(1);
227 DebugLoc dl = N->getDebugLoc();
229 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2));
230 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2));
232 // Handle endianness of the load.
233 if (TLI.isBigEndian())
236 // Modified the chain - switch anything that used the old chain to use
238 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
242 //===--------------------------------------------------------------------===//
243 // Generic Operand Expansion.
244 //===--------------------------------------------------------------------===//
246 SDValue DAGTypeLegalizer::ExpandOp_BIT_CONVERT(SDNode *N) {
247 DebugLoc dl = N->getDebugLoc();
248 if (N->getValueType(0).isVector()) {
249 // An illegal expanding type is being converted to a legal vector type.
250 // Make a two element vector out of the expanded parts and convert that
251 // instead, but only if the new vector type is legal (otherwise there
252 // is no point, and it might create expansion loops). For example, on
253 // x86 this turns v1i64 = BIT_CONVERT i64 into v1i64 = BIT_CONVERT v2i32.
254 MVT OVT = N->getOperand(0).getValueType();
255 MVT NVT = MVT::getVectorVT(TLI.getTypeToTransformTo(OVT), 2);
257 if (isTypeLegal(NVT)) {
259 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]);
261 if (TLI.isBigEndian())
262 std::swap(Parts[0], Parts[1]);
264 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2);
265 return DAG.getNode(ISD::BIT_CONVERT, dl, N->getValueType(0), Vec);
269 // Otherwise, store to a temporary and load out again as the new type.
270 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
273 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
274 // The vector type is legal but the element type needs expansion.
275 MVT VecVT = N->getValueType(0);
276 unsigned NumElts = VecVT.getVectorNumElements();
277 MVT OldVT = N->getOperand(0).getValueType();
278 MVT NewVT = TLI.getTypeToTransformTo(OldVT);
279 DebugLoc dl = N->getDebugLoc();
281 // Build a vector of twice the length out of the expanded elements.
282 // For example <3 x i64> -> <6 x i32>.
283 std::vector<SDValue> NewElts;
284 NewElts.reserve(NumElts*2);
286 for (unsigned i = 0; i < NumElts; ++i) {
288 GetExpandedOp(N->getOperand(i), Lo, Hi);
289 if (TLI.isBigEndian())
291 NewElts.push_back(Lo);
292 NewElts.push_back(Hi);
295 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
296 MVT::getVectorVT(NewVT, NewElts.size()),
297 &NewElts[0], NewElts.size());
299 // Convert the new vector to the old vector type.
300 return DAG.getNode(ISD::BIT_CONVERT, dl, VecVT, NewVec);
303 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
305 GetExpandedOp(N->getOperand(0), Lo, Hi);
306 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
309 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
310 // The vector type is legal but the element type needs expansion.
311 MVT VecVT = N->getValueType(0);
312 unsigned NumElts = VecVT.getVectorNumElements();
313 DebugLoc dl = N->getDebugLoc();
315 SDValue Val = N->getOperand(1);
316 MVT OldEVT = Val.getValueType();
317 MVT NewEVT = TLI.getTypeToTransformTo(OldEVT);
319 assert(OldEVT == VecVT.getVectorElementType() &&
320 "Inserted element type doesn't match vector element type!");
322 // Bitconvert to a vector of twice the length with elements of the expanded
323 // type, insert the expanded vector elements, and then convert back.
324 MVT NewVecVT = MVT::getVectorVT(NewEVT, NumElts*2);
325 SDValue NewVec = DAG.getNode(ISD::BIT_CONVERT, dl,
326 NewVecVT, N->getOperand(0));
329 GetExpandedOp(Val, Lo, Hi);
330 if (TLI.isBigEndian())
333 SDValue Idx = N->getOperand(2);
334 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
335 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
336 Idx = DAG.getNode(ISD::ADD, dl,
337 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1));
338 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
340 // Convert the new vector to the old vector type.
341 return DAG.getNode(ISD::BIT_CONVERT, dl, VecVT, NewVec);
344 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
345 DebugLoc dl = N->getDebugLoc();
346 MVT VT = N->getValueType(0);
347 unsigned NumElts = VT.getVectorNumElements();
348 SmallVector<SDValue, 16> Ops(NumElts);
349 Ops[0] = N->getOperand(0);
350 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
351 for (unsigned i = 1; i < NumElts; ++i)
353 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts);
356 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
357 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
358 assert(OpNo == 1 && "Can only expand the stored value so far");
359 DebugLoc dl = N->getDebugLoc();
361 StoreSDNode *St = cast<StoreSDNode>(N);
362 MVT NVT = TLI.getTypeToTransformTo(St->getValue().getValueType());
363 SDValue Chain = St->getChain();
364 SDValue Ptr = St->getBasePtr();
365 int SVOffset = St->getSrcValueOffset();
366 unsigned Alignment = St->getAlignment();
367 bool isVolatile = St->isVolatile();
369 assert(NVT.isByteSized() && "Expanded type not byte sized!");
370 unsigned IncrementSize = NVT.getSizeInBits() / 8;
373 GetExpandedOp(St->getValue(), Lo, Hi);
375 if (TLI.isBigEndian())
378 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getSrcValue(), SVOffset,
379 isVolatile, Alignment);
381 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
382 DAG.getIntPtrConstant(IncrementSize));
383 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!");
384 Hi = DAG.getStore(Chain, dl, Hi, Ptr, St->getSrcValue(),
385 SVOffset + IncrementSize,
386 isVolatile, MinAlign(Alignment, IncrementSize));
388 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
392 //===--------------------------------------------------------------------===//
393 // Generic Result Splitting.
394 //===--------------------------------------------------------------------===//
396 // Be careful to make no assumptions about which of Lo/Hi is stored first in
397 // memory (for vectors it is always Lo first followed by Hi in the following
398 // bytes; for integers and floats it is Lo first if and only if the machine is
401 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N,
402 SDValue &Lo, SDValue &Hi) {
403 // A MERGE_VALUES node can produce any number of values. We know that the
404 // first illegal one needs to be expanded into Lo/Hi.
407 // The string of legal results gets turned into input operands, which have
409 for (i = 0; isTypeLegal(N->getValueType(i)); ++i)
410 ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i)));
412 // The first illegal result must be the one that needs to be expanded.
413 GetSplitOp(N->getOperand(i), Lo, Hi);
415 // Legalize the rest of the results into the input operands whether they are
417 unsigned e = N->getNumValues();
418 for (++i; i != e; ++i)
419 ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i)));
422 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
424 SDValue LL, LH, RL, RH;
425 DebugLoc dl = N->getDebugLoc();
426 GetSplitOp(N->getOperand(1), LL, LH);
427 GetSplitOp(N->getOperand(2), RL, RH);
429 SDValue Cond = N->getOperand(0);
430 Lo = DAG.getNode(ISD::SELECT, dl, LL.getValueType(), Cond, LL, RL);
431 Hi = DAG.getNode(ISD::SELECT, dl, LH.getValueType(), Cond, LH, RH);
434 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
436 SDValue LL, LH, RL, RH;
437 DebugLoc dl = N->getDebugLoc();
438 GetSplitOp(N->getOperand(2), LL, LH);
439 GetSplitOp(N->getOperand(3), RL, RH);
441 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
442 N->getOperand(1), LL, RL, N->getOperand(4));
443 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
444 N->getOperand(1), LH, RH, N->getOperand(4));
447 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
449 DebugLoc dl = N->getDebugLoc();
450 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
451 Lo = DAG.getUNDEF(LoVT);
452 Hi = DAG.getUNDEF(HiVT);