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 if (InVT.isVector() && OutVT.isInteger()) {
96 // Handle cases like i64 = BIT_CONVERT v1i64 on x86, where the operand
97 // is legal but the result is not.
98 MVT NVT = MVT::getVectorVT(NOutVT, 2);
100 if (isTypeLegal(NVT)) {
101 SDValue CastInOp = DAG.getNode(ISD::BIT_CONVERT, dl, NVT, InOp);
102 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp,
103 DAG.getIntPtrConstant(0));
104 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NOutVT, CastInOp,
105 DAG.getIntPtrConstant(1));
107 if (TLI.isBigEndian())
114 // Lower the bit-convert to a store/load from the stack.
115 assert(NOutVT.isByteSized() && "Expanded type not byte sized!");
117 // Create the stack frame object. Make sure it is aligned for both
118 // the source and expanded destination types.
120 TLI.getTargetData()->getPrefTypeAlignment(NOutVT.getTypeForMVT());
121 SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment);
122 int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
123 const Value *SV = PseudoSourceValue::getFixedStack(SPFI);
125 // Emit a store to the stack slot.
126 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);
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 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 MVT OldVT = N->getValueType(0);
173 MVT NewVT = TLI.getTypeToTransformTo(OldVT);
175 SDValue NewVec = DAG.getNode(ISD::BIT_CONVERT, dl,
176 MVT::getVectorVT(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 MVT NVT = TLI.getTypeToTransformTo(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();
210 assert(NVT.isByteSized() && "Expanded type not byte sized!");
212 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getSrcValue(), SVOffset,
213 isVolatile, Alignment);
215 // Increment the pointer to the other half.
216 unsigned IncrementSize = NVT.getSizeInBits() / 8;
217 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
218 DAG.getIntPtrConstant(IncrementSize));
219 Hi = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getSrcValue(),
220 SVOffset+IncrementSize,
221 isVolatile, MinAlign(Alignment, IncrementSize));
223 // Build a factor node to remember that this load is independent of the
225 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
228 // Handle endianness of the load.
229 if (TLI.isBigEndian())
232 // Modified the chain - switch anything that used the old chain to use
234 ReplaceValueWith(SDValue(N, 1), Chain);
237 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
238 MVT NVT = TLI.getTypeToTransformTo(N->getValueType(0));
239 SDValue Chain = N->getOperand(0);
240 SDValue Ptr = N->getOperand(1);
241 DebugLoc dl = N->getDebugLoc();
243 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2));
244 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2));
246 // Handle endianness of the load.
247 if (TLI.isBigEndian())
250 // Modified the chain - switch anything that used the old chain to use
252 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
256 //===--------------------------------------------------------------------===//
257 // Generic Operand Expansion.
258 //===--------------------------------------------------------------------===//
260 SDValue DAGTypeLegalizer::ExpandOp_BIT_CONVERT(SDNode *N) {
261 DebugLoc dl = N->getDebugLoc();
262 if (N->getValueType(0).isVector()) {
263 // An illegal expanding type is being converted to a legal vector type.
264 // Make a two element vector out of the expanded parts and convert that
265 // instead, but only if the new vector type is legal (otherwise there
266 // is no point, and it might create expansion loops). For example, on
267 // x86 this turns v1i64 = BIT_CONVERT i64 into v1i64 = BIT_CONVERT v2i32.
268 MVT OVT = N->getOperand(0).getValueType();
269 MVT NVT = MVT::getVectorVT(TLI.getTypeToTransformTo(OVT), 2);
271 if (isTypeLegal(NVT)) {
273 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]);
275 if (TLI.isBigEndian())
276 std::swap(Parts[0], Parts[1]);
278 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2);
279 return DAG.getNode(ISD::BIT_CONVERT, dl, N->getValueType(0), Vec);
283 // Otherwise, store to a temporary and load out again as the new type.
284 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
287 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
288 // The vector type is legal but the element type needs expansion.
289 MVT VecVT = N->getValueType(0);
290 unsigned NumElts = VecVT.getVectorNumElements();
291 MVT OldVT = N->getOperand(0).getValueType();
292 MVT NewVT = TLI.getTypeToTransformTo(OldVT);
293 DebugLoc dl = N->getDebugLoc();
295 assert(OldVT == VecVT.getVectorElementType() &&
296 "BUILD_VECTOR operand type doesn't match vector element type!");
298 // Build a vector of twice the length out of the expanded elements.
299 // For example <3 x i64> -> <6 x i32>.
300 std::vector<SDValue> NewElts;
301 NewElts.reserve(NumElts*2);
303 for (unsigned i = 0; i < NumElts; ++i) {
305 GetExpandedOp(N->getOperand(i), Lo, Hi);
306 if (TLI.isBigEndian())
308 NewElts.push_back(Lo);
309 NewElts.push_back(Hi);
312 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
313 MVT::getVectorVT(NewVT, NewElts.size()),
314 &NewElts[0], NewElts.size());
316 // Convert the new vector to the old vector type.
317 return DAG.getNode(ISD::BIT_CONVERT, dl, VecVT, NewVec);
320 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
322 GetExpandedOp(N->getOperand(0), Lo, Hi);
323 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
326 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
327 // The vector type is legal but the element type needs expansion.
328 MVT VecVT = N->getValueType(0);
329 unsigned NumElts = VecVT.getVectorNumElements();
330 DebugLoc dl = N->getDebugLoc();
332 SDValue Val = N->getOperand(1);
333 MVT OldEVT = Val.getValueType();
334 MVT NewEVT = TLI.getTypeToTransformTo(OldEVT);
336 assert(OldEVT == VecVT.getVectorElementType() &&
337 "Inserted element type doesn't match vector element type!");
339 // Bitconvert to a vector of twice the length with elements of the expanded
340 // type, insert the expanded vector elements, and then convert back.
341 MVT NewVecVT = MVT::getVectorVT(NewEVT, NumElts*2);
342 SDValue NewVec = DAG.getNode(ISD::BIT_CONVERT, dl,
343 NewVecVT, N->getOperand(0));
346 GetExpandedOp(Val, Lo, Hi);
347 if (TLI.isBigEndian())
350 SDValue Idx = N->getOperand(2);
351 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
352 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
353 Idx = DAG.getNode(ISD::ADD, dl,
354 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1));
355 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
357 // Convert the new vector to the old vector type.
358 return DAG.getNode(ISD::BIT_CONVERT, dl, VecVT, NewVec);
361 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
362 DebugLoc dl = N->getDebugLoc();
363 MVT VT = N->getValueType(0);
364 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
365 "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
366 unsigned NumElts = VT.getVectorNumElements();
367 SmallVector<SDValue, 16> Ops(NumElts);
368 Ops[0] = N->getOperand(0);
369 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
370 for (unsigned i = 1; i < NumElts; ++i)
372 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts);
375 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
376 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
377 assert(OpNo == 1 && "Can only expand the stored value so far");
378 DebugLoc dl = N->getDebugLoc();
380 StoreSDNode *St = cast<StoreSDNode>(N);
381 MVT NVT = TLI.getTypeToTransformTo(St->getValue().getValueType());
382 SDValue Chain = St->getChain();
383 SDValue Ptr = St->getBasePtr();
384 int SVOffset = St->getSrcValueOffset();
385 unsigned Alignment = St->getAlignment();
386 bool isVolatile = St->isVolatile();
388 assert(NVT.isByteSized() && "Expanded type not byte sized!");
389 unsigned IncrementSize = NVT.getSizeInBits() / 8;
392 GetExpandedOp(St->getValue(), Lo, Hi);
394 if (TLI.isBigEndian())
397 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getSrcValue(), SVOffset,
398 isVolatile, Alignment);
400 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
401 DAG.getIntPtrConstant(IncrementSize));
402 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!");
403 Hi = DAG.getStore(Chain, dl, Hi, Ptr, St->getSrcValue(),
404 SVOffset + IncrementSize,
405 isVolatile, MinAlign(Alignment, IncrementSize));
407 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
411 //===--------------------------------------------------------------------===//
412 // Generic Result Splitting.
413 //===--------------------------------------------------------------------===//
415 // Be careful to make no assumptions about which of Lo/Hi is stored first in
416 // memory (for vectors it is always Lo first followed by Hi in the following
417 // bytes; for integers and floats it is Lo first if and only if the machine is
420 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N,
421 SDValue &Lo, SDValue &Hi) {
422 // A MERGE_VALUES node can produce any number of values. We know that the
423 // first illegal one needs to be expanded into Lo/Hi.
426 // The string of legal results gets turned into input operands, which have
428 for (i = 0; isTypeLegal(N->getValueType(i)); ++i)
429 ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i)));
431 // The first illegal result must be the one that needs to be expanded.
432 GetSplitOp(N->getOperand(i), Lo, Hi);
434 // Legalize the rest of the results into the input operands whether they are
436 unsigned e = N->getNumValues();
437 for (++i; i != e; ++i)
438 ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i)));
441 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
443 SDValue LL, LH, RL, RH;
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);
449 Lo = DAG.getNode(ISD::SELECT, dl, LL.getValueType(), Cond, LL, RL);
450 Hi = DAG.getNode(ISD::SELECT, dl, LH.getValueType(), Cond, LH, RH);
453 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
455 SDValue LL, LH, RL, RH;
456 DebugLoc dl = N->getDebugLoc();
457 GetSplitOp(N->getOperand(2), LL, LH);
458 GetSplitOp(N->getOperand(3), RL, RH);
460 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
461 N->getOperand(1), LL, RL, N->getOperand(4));
462 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
463 N->getOperand(1), LH, RH, N->getOperand(4));
466 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
468 DebugLoc dl = N->getDebugLoc();
469 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
470 Lo = DAG.getUNDEF(LoVT);
471 Hi = DAG.getUNDEF(HiVT);