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 MVT OutVT = N->getValueType(0);
38 MVT NOutVT = TLI.getTypeToTransformTo(OutVT);
39 SDValue InOp = N->getOperand(0);
40 MVT 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 MVT InNVT = MVT::getVectorVT(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 MVT NVT = MVT::getVectorVT(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.getTypeForMVT(
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);
127 // Load the first half from the stack slot.
128 Lo = DAG.getLoad(NOutVT, dl, Store, StackPtr, SV, 0);
130 // Increment the pointer to the other half.
131 unsigned IncrementSize = NOutVT.getSizeInBits() / 8;
132 StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
133 DAG.getIntPtrConstant(IncrementSize));
135 // Load the second half from the stack slot.
136 Hi = DAG.getLoad(NOutVT, dl, Store, StackPtr, SV, IncrementSize, false,
137 MinAlign(Alignment, IncrementSize));
139 // Handle endianness of the load.
140 if (TLI.isBigEndian())
144 void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
146 // Return the operands.
147 Lo = N->getOperand(0);
148 Hi = N->getOperand(1);
151 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
153 GetExpandedOp(N->getOperand(0), Lo, Hi);
154 SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ?
157 assert(Part.getValueType() == N->getValueType(0) &&
158 "Type twice as big as expanded type not itself expanded!");
160 GetPairElements(Part, Lo, Hi);
163 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
165 SDValue OldVec = N->getOperand(0);
166 unsigned OldElts = OldVec.getValueType().getVectorNumElements();
167 DebugLoc dl = N->getDebugLoc();
169 // Convert to a vector of the expanded element type, for example
170 // <3 x i64> -> <6 x i32>.
171 MVT OldVT = N->getValueType(0);
172 MVT NewVT = TLI.getTypeToTransformTo(OldVT);
174 SDValue NewVec = DAG.getNode(ISD::BIT_CONVERT, dl,
175 MVT::getVectorVT(NewVT, 2*OldElts),
178 // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector.
179 SDValue Idx = N->getOperand(1);
181 // Make sure the type of Idx is big enough to hold the new values.
182 if (Idx.getValueType().bitsLT(TLI.getPointerTy()))
183 Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
185 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
186 Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
188 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
189 DAG.getConstant(1, Idx.getValueType()));
190 Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, NewVT, NewVec, Idx);
192 if (TLI.isBigEndian())
196 void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo,
198 assert(ISD::isNormalLoad(N) && "This routine only for normal loads!");
199 DebugLoc dl = N->getDebugLoc();
201 LoadSDNode *LD = cast<LoadSDNode>(N);
202 MVT NVT = TLI.getTypeToTransformTo(LD->getValueType(0));
203 SDValue Chain = LD->getChain();
204 SDValue Ptr = LD->getBasePtr();
205 int SVOffset = LD->getSrcValueOffset();
206 unsigned Alignment = LD->getAlignment();
207 bool isVolatile = LD->isVolatile();
209 assert(NVT.isByteSized() && "Expanded type not byte sized!");
211 Lo = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getSrcValue(), SVOffset,
212 isVolatile, Alignment);
214 // Increment the pointer to the other half.
215 unsigned IncrementSize = NVT.getSizeInBits() / 8;
216 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
217 DAG.getIntPtrConstant(IncrementSize));
218 Hi = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getSrcValue(),
219 SVOffset+IncrementSize,
220 isVolatile, MinAlign(Alignment, IncrementSize));
222 // Build a factor node to remember that this load is independent of the
224 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
227 // Handle endianness of the load.
228 if (TLI.isBigEndian())
231 // Modified the chain - switch anything that used the old chain to use
233 ReplaceValueWith(SDValue(N, 1), Chain);
236 void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) {
237 MVT NVT = TLI.getTypeToTransformTo(N->getValueType(0));
238 SDValue Chain = N->getOperand(0);
239 SDValue Ptr = N->getOperand(1);
240 DebugLoc dl = N->getDebugLoc();
242 Lo = DAG.getVAArg(NVT, dl, Chain, Ptr, N->getOperand(2));
243 Hi = DAG.getVAArg(NVT, dl, Lo.getValue(1), Ptr, N->getOperand(2));
245 // Handle endianness of the load.
246 if (TLI.isBigEndian())
249 // Modified the chain - switch anything that used the old chain to use
251 ReplaceValueWith(SDValue(N, 1), Hi.getValue(1));
255 //===--------------------------------------------------------------------===//
256 // Generic Operand Expansion.
257 //===--------------------------------------------------------------------===//
259 SDValue DAGTypeLegalizer::ExpandOp_BIT_CONVERT(SDNode *N) {
260 DebugLoc dl = N->getDebugLoc();
261 if (N->getValueType(0).isVector()) {
262 // An illegal expanding type is being converted to a legal vector type.
263 // Make a two element vector out of the expanded parts and convert that
264 // instead, but only if the new vector type is legal (otherwise there
265 // is no point, and it might create expansion loops). For example, on
266 // x86 this turns v1i64 = BIT_CONVERT i64 into v1i64 = BIT_CONVERT v2i32.
267 MVT OVT = N->getOperand(0).getValueType();
268 MVT NVT = MVT::getVectorVT(TLI.getTypeToTransformTo(OVT), 2);
270 if (isTypeLegal(NVT)) {
272 GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]);
274 if (TLI.isBigEndian())
275 std::swap(Parts[0], Parts[1]);
277 SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT, Parts, 2);
278 return DAG.getNode(ISD::BIT_CONVERT, dl, N->getValueType(0), Vec);
282 // Otherwise, store to a temporary and load out again as the new type.
283 return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0));
286 SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
287 // The vector type is legal but the element type needs expansion.
288 MVT VecVT = N->getValueType(0);
289 unsigned NumElts = VecVT.getVectorNumElements();
290 MVT OldVT = N->getOperand(0).getValueType();
291 MVT NewVT = TLI.getTypeToTransformTo(OldVT);
292 DebugLoc dl = N->getDebugLoc();
294 assert(OldVT == VecVT.getVectorElementType() &&
295 "BUILD_VECTOR operand type doesn't match vector element type!");
297 // Build a vector of twice the length out of the expanded elements.
298 // For example <3 x i64> -> <6 x i32>.
299 std::vector<SDValue> NewElts;
300 NewElts.reserve(NumElts*2);
302 for (unsigned i = 0; i < NumElts; ++i) {
304 GetExpandedOp(N->getOperand(i), Lo, Hi);
305 if (TLI.isBigEndian())
307 NewElts.push_back(Lo);
308 NewElts.push_back(Hi);
311 SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, dl,
312 MVT::getVectorVT(NewVT, NewElts.size()),
313 &NewElts[0], NewElts.size());
315 // Convert the new vector to the old vector type.
316 return DAG.getNode(ISD::BIT_CONVERT, dl, VecVT, NewVec);
319 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
321 GetExpandedOp(N->getOperand(0), Lo, Hi);
322 return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
325 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
326 // The vector type is legal but the element type needs expansion.
327 MVT VecVT = N->getValueType(0);
328 unsigned NumElts = VecVT.getVectorNumElements();
329 DebugLoc dl = N->getDebugLoc();
331 SDValue Val = N->getOperand(1);
332 MVT OldEVT = Val.getValueType();
333 MVT NewEVT = TLI.getTypeToTransformTo(OldEVT);
335 assert(OldEVT == VecVT.getVectorElementType() &&
336 "Inserted element type doesn't match vector element type!");
338 // Bitconvert to a vector of twice the length with elements of the expanded
339 // type, insert the expanded vector elements, and then convert back.
340 MVT NewVecVT = MVT::getVectorVT(NewEVT, NumElts*2);
341 SDValue NewVec = DAG.getNode(ISD::BIT_CONVERT, dl,
342 NewVecVT, N->getOperand(0));
345 GetExpandedOp(Val, Lo, Hi);
346 if (TLI.isBigEndian())
349 SDValue Idx = N->getOperand(2);
350 Idx = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, Idx);
351 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Lo, Idx);
352 Idx = DAG.getNode(ISD::ADD, dl,
353 Idx.getValueType(), Idx, DAG.getIntPtrConstant(1));
354 NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, dl, NewVecVT, NewVec, Hi, Idx);
356 // Convert the new vector to the old vector type.
357 return DAG.getNode(ISD::BIT_CONVERT, dl, VecVT, NewVec);
360 SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) {
361 DebugLoc dl = N->getDebugLoc();
362 MVT VT = N->getValueType(0);
363 assert(VT.getVectorElementType() == N->getOperand(0).getValueType() &&
364 "SCALAR_TO_VECTOR operand type doesn't match vector element type!");
365 unsigned NumElts = VT.getVectorNumElements();
366 SmallVector<SDValue, 16> Ops(NumElts);
367 Ops[0] = N->getOperand(0);
368 SDValue UndefVal = DAG.getUNDEF(Ops[0].getValueType());
369 for (unsigned i = 1; i < NumElts; ++i)
371 return DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], NumElts);
374 SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) {
375 assert(ISD::isNormalStore(N) && "This routine only for normal stores!");
376 assert(OpNo == 1 && "Can only expand the stored value so far");
377 DebugLoc dl = N->getDebugLoc();
379 StoreSDNode *St = cast<StoreSDNode>(N);
380 MVT NVT = TLI.getTypeToTransformTo(St->getValue().getValueType());
381 SDValue Chain = St->getChain();
382 SDValue Ptr = St->getBasePtr();
383 int SVOffset = St->getSrcValueOffset();
384 unsigned Alignment = St->getAlignment();
385 bool isVolatile = St->isVolatile();
387 assert(NVT.isByteSized() && "Expanded type not byte sized!");
388 unsigned IncrementSize = NVT.getSizeInBits() / 8;
391 GetExpandedOp(St->getValue(), Lo, Hi);
393 if (TLI.isBigEndian())
396 Lo = DAG.getStore(Chain, dl, Lo, Ptr, St->getSrcValue(), SVOffset,
397 isVolatile, Alignment);
399 Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
400 DAG.getIntPtrConstant(IncrementSize));
401 assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!");
402 Hi = DAG.getStore(Chain, dl, Hi, Ptr, St->getSrcValue(),
403 SVOffset + IncrementSize,
404 isVolatile, MinAlign(Alignment, IncrementSize));
406 return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
410 //===--------------------------------------------------------------------===//
411 // Generic Result Splitting.
412 //===--------------------------------------------------------------------===//
414 // Be careful to make no assumptions about which of Lo/Hi is stored first in
415 // memory (for vectors it is always Lo first followed by Hi in the following
416 // bytes; for integers and floats it is Lo first if and only if the machine is
419 void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N,
420 SDValue &Lo, SDValue &Hi) {
421 // A MERGE_VALUES node can produce any number of values. We know that the
422 // first illegal one needs to be expanded into Lo/Hi.
425 // The string of legal results gets turned into input operands, which have
427 for (i = 0; isTypeLegal(N->getValueType(i)); ++i)
428 ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i)));
430 // The first illegal result must be the one that needs to be expanded.
431 GetSplitOp(N->getOperand(i), Lo, Hi);
433 // Legalize the rest of the results into the input operands whether they are
435 unsigned e = N->getNumValues();
436 for (++i; i != e; ++i)
437 ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i)));
440 void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo,
442 SDValue LL, LH, RL, RH;
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);
448 Lo = DAG.getNode(ISD::SELECT, dl, LL.getValueType(), Cond, LL, RL);
449 Hi = DAG.getNode(ISD::SELECT, dl, LH.getValueType(), Cond, LH, RH);
452 void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo,
454 SDValue LL, LH, RL, RH;
455 DebugLoc dl = N->getDebugLoc();
456 GetSplitOp(N->getOperand(2), LL, LH);
457 GetSplitOp(N->getOperand(3), RL, RH);
459 Lo = DAG.getNode(ISD::SELECT_CC, dl, LL.getValueType(), N->getOperand(0),
460 N->getOperand(1), LL, RL, N->getOperand(4));
461 Hi = DAG.getNode(ISD::SELECT_CC, dl, LH.getValueType(), N->getOperand(0),
462 N->getOperand(1), LH, RH, N->getOperand(4));
465 void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) {
467 DebugLoc dl = N->getDebugLoc();
468 GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
469 Lo = DAG.getUNDEF(LoVT);
470 Hi = DAG.getUNDEF(HiVT);