1 //===-- LegalizeTypes.cpp - Common code for DAG type legalizer ------------===//
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 the SelectionDAG::LegalizeTypes method. It transforms
11 // an arbitrary well-formed SelectionDAG to only consist of legal types. This
12 // is common code shared among the LegalizeTypes*.cpp files.
14 //===----------------------------------------------------------------------===//
16 #include "LegalizeTypes.h"
17 #include "llvm/CallingConv.h"
18 #include "llvm/Support/CommandLine.h"
19 #include "llvm/Target/TargetData.h"
22 /// run - This is the main entry point for the type legalizer. This does a
23 /// top-down traversal of the dag, legalizing types as it goes.
24 void DAGTypeLegalizer::run() {
25 // Create a dummy node (which is not added to allnodes), that adds a reference
26 // to the root node, preventing it from being deleted, and tracking any
27 // changes of the root.
28 HandleSDNode Dummy(DAG.getRoot());
30 // The root of the dag may dangle to deleted nodes until the type legalizer is
31 // done. Set it to null to avoid confusion.
32 DAG.setRoot(SDValue());
34 // Walk all nodes in the graph, assigning them a NodeId of 'ReadyToProcess'
35 // (and remembering them) if they are leaves and assigning 'NewNode' if
37 for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(),
38 E = DAG.allnodes_end(); I != E; ++I) {
39 if (I->getNumOperands() == 0) {
40 I->setNodeId(ReadyToProcess);
41 Worklist.push_back(I);
43 I->setNodeId(NewNode);
47 // Now that we have a set of nodes to process, handle them all.
48 while (!Worklist.empty()) {
49 SDNode *N = Worklist.back();
51 assert(N->getNodeId() == ReadyToProcess &&
52 "Node should be ready if on worklist!");
54 if (IgnoreNodeResults(N))
57 // Scan the values produced by the node, checking to see if any result
59 for (unsigned i = 0, NumResults = N->getNumValues(); i < NumResults; ++i) {
60 MVT ResultVT = N->getValueType(i);
61 switch (getTypeAction(ResultVT)) {
63 assert(false && "Unknown action!");
67 PromoteIntegerResult(N, i);
70 ExpandIntegerResult(N, i);
73 SoftenFloatResult(N, i);
76 ExpandFloatResult(N, i);
79 ScalarizeVectorResult(N, i);
82 SplitVectorResult(N, i);
88 // Scan the operand list for the node, handling any nodes with operands that
91 unsigned NumOperands = N->getNumOperands();
92 bool NeedsRevisit = false;
94 for (i = 0; i != NumOperands; ++i) {
95 if (IgnoreNodeResults(N->getOperand(i).getNode()))
98 MVT OpVT = N->getOperand(i).getValueType();
99 switch (getTypeAction(OpVT)) {
101 assert(false && "Unknown action!");
105 NeedsRevisit = PromoteIntegerOperand(N, i);
108 NeedsRevisit = ExpandIntegerOperand(N, i);
111 NeedsRevisit = SoftenFloatOperand(N, i);
114 NeedsRevisit = ExpandFloatOperand(N, i);
116 case ScalarizeVector:
117 NeedsRevisit = ScalarizeVectorOperand(N, i);
120 NeedsRevisit = SplitVectorOperand(N, i);
126 // If the node needs revisiting, don't add all users to the worklist etc.
130 if (i == NumOperands) {
131 DEBUG(cerr << "Legally typed node: "; N->dump(&DAG); cerr << "\n");
136 // If we reach here, the node was processed, potentially creating new nodes.
137 // Mark it as processed and add its users to the worklist as appropriate.
138 N->setNodeId(Processed);
140 for (SDNode::use_iterator UI = N->use_begin(), E = N->use_end();
143 int NodeId = User->getNodeId();
144 assert(NodeId != ReadyToProcess && NodeId != Processed &&
145 "Invalid node id for user of unprocessed node!");
147 // This node has two options: it can either be a new node or its Node ID
148 // may be a count of the number of operands it has that are not ready.
150 User->setNodeId(NodeId-1);
152 // If this was the last use it was waiting on, add it to the ready list.
153 if (NodeId-1 == ReadyToProcess)
154 Worklist.push_back(User);
158 // Otherwise, this node is new: this is the first operand of it that
159 // became ready. Its new NodeId is the number of operands it has minus 1
160 // (as this node is now processed).
161 assert(NodeId == NewNode && "Unknown node ID!");
162 User->setNodeId(User->getNumOperands()-1);
164 // If the node only has a single operand, it is now ready.
165 if (User->getNumOperands() == 1)
166 Worklist.push_back(User);
170 // If the root changed (e.g. it was a dead load, update the root).
171 DAG.setRoot(Dummy.getValue());
175 // Remove dead nodes. This is important to do for cleanliness but also before
176 // the checking loop below. Implicit folding by the DAG.getNode operators can
177 // cause unreachable nodes to be around with their flags set to new.
178 DAG.RemoveDeadNodes();
180 // In a debug build, scan all the nodes to make sure we found them all. This
181 // ensures that there are no cycles and that everything got processed.
183 for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(),
184 E = DAG.allnodes_end(); I != E; ++I) {
187 // Check that all result types are legal.
188 if (!IgnoreNodeResults(I))
189 for (unsigned i = 0, NumVals = I->getNumValues(); i < NumVals; ++i)
190 if (!isTypeLegal(I->getValueType(i))) {
191 cerr << "Result type " << i << " illegal!\n";
195 // Check that all operand types are legal.
196 for (unsigned i = 0, NumOps = I->getNumOperands(); i < NumOps; ++i)
197 if (!IgnoreNodeResults(I->getOperand(i).getNode()) &&
198 !isTypeLegal(I->getOperand(i).getValueType())) {
199 cerr << "Operand type " << i << " illegal!\n";
203 if (I->getNodeId() != Processed) {
204 if (I->getNodeId() == NewNode)
205 cerr << "New node not 'noticed'?\n";
206 else if (I->getNodeId() > 0)
207 cerr << "Operand not processed?\n";
208 else if (I->getNodeId() == ReadyToProcess)
209 cerr << "Not added to worklist?\n";
214 I->dump(&DAG); cerr << "\n";
221 /// AnalyzeNewNode - The specified node is the root of a subtree of potentially
222 /// new nodes. Correct any processed operands (this may change the node) and
223 /// calculate the NodeId. If the node itself changes to a processed node, it
224 /// is not remapped - the caller needs to take care of this.
225 /// Returns the potentially changed node.
226 SDNode *DAGTypeLegalizer::AnalyzeNewNode(SDNode *N) {
227 // If this was an existing node that is already done, we're done.
228 if (N->getNodeId() != NewNode)
231 // Remove any stale map entries.
234 // Okay, we know that this node is new. Recursively walk all of its operands
235 // to see if they are new also. The depth of this walk is bounded by the size
236 // of the new tree that was constructed (usually 2-3 nodes), so we don't worry
237 // about revisiting of nodes.
239 // As we walk the operands, keep track of the number of nodes that are
240 // processed. If non-zero, this will become the new nodeid of this node.
241 // Already processed operands may need to be remapped to the node that
242 // replaced them, which can result in our node changing. Since remapping
243 // is rare, the code tries to minimize overhead in the non-remapping case.
245 SmallVector<SDValue, 8> NewOps;
246 unsigned NumProcessed = 0;
247 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
248 SDValue OrigOp = N->getOperand(i);
251 if (Op.getNode()->getNodeId() == Processed)
253 else if (Op.getNode()->getNodeId() == NewNode)
256 if (Op.getNode()->getNodeId() == Processed)
259 if (!NewOps.empty()) {
260 // Some previous operand changed. Add this one to the list.
261 NewOps.push_back(Op);
262 } else if (Op != OrigOp) {
263 // This is the first operand to change - add all operands so far.
264 for (unsigned j = 0; j < i; ++j)
265 NewOps.push_back(N->getOperand(j));
266 NewOps.push_back(Op);
270 // Some operands changed - update the node.
271 if (!NewOps.empty()) {
272 SDNode *M = DAG.UpdateNodeOperands(SDValue(N, 0), &NewOps[0],
273 NewOps.size()).getNode();
275 if (M->getNodeId() != NewNode)
276 // It morphed into a previously analyzed node - nothing more to do.
279 // It morphed into a different new node. Do the equivalent of passing
280 // it to AnalyzeNewNode: expunge it and calculate the NodeId.
286 // Calculate the NodeId.
287 N->setNodeId(N->getNumOperands()-NumProcessed);
288 if (N->getNodeId() == ReadyToProcess)
289 Worklist.push_back(N);
294 /// AnalyzeNewValue - Call AnalyzeNewNode, updating the node in Val if needed.
295 /// If the node changes to a processed node, then remap it.
296 void DAGTypeLegalizer::AnalyzeNewValue(SDValue &Val) {
297 SDNode *N(Val.getNode());
298 // If this was an existing node that is already done, avoid remapping it.
299 if (N->getNodeId() != NewNode)
301 SDNode *M(AnalyzeNewNode(N));
304 if (M->getNodeId() == Processed)
305 // It morphed into an already processed node - remap it.
311 /// NodeUpdateListener - This class is a DAGUpdateListener that listens for
312 /// updates to nodes and recomputes their ready state.
313 class VISIBILITY_HIDDEN NodeUpdateListener :
314 public SelectionDAG::DAGUpdateListener {
315 DAGTypeLegalizer &DTL;
317 explicit NodeUpdateListener(DAGTypeLegalizer &dtl) : DTL(dtl) {}
319 virtual void NodeDeleted(SDNode *N, SDNode *E) {
320 assert(N->getNodeId() != DAGTypeLegalizer::Processed &&
321 N->getNodeId() != DAGTypeLegalizer::ReadyToProcess &&
322 "RAUW deleted processed node!");
323 // It is possible, though rare, for the deleted node N to occur as a
324 // target in a map, so note the replacement N -> E in ReplacedValues.
325 assert(E && "Node not replaced?");
326 DTL.NoteDeletion(N, E);
329 virtual void NodeUpdated(SDNode *N) {
330 // Node updates can mean pretty much anything. It is possible that an
331 // operand was set to something already processed (f.e.) in which case
332 // this node could become ready. Recompute its flags.
333 assert(N->getNodeId() != DAGTypeLegalizer::Processed &&
334 N->getNodeId() != DAGTypeLegalizer::ReadyToProcess &&
335 "RAUW updated processed node!");
336 DTL.ReanalyzeNode(N);
342 /// ReplaceValueWith - The specified value was legalized to the specified other
343 /// value. If they are different, update the DAG and NodeIds replacing any uses
344 /// of From to use To instead.
345 void DAGTypeLegalizer::ReplaceValueWith(SDValue From, SDValue To) {
346 if (From == To) return;
348 // If expansion produced new nodes, make sure they are properly marked.
349 ExpungeNode(From.getNode());
350 AnalyzeNewValue(To); // Expunges To.
352 // Anything that used the old node should now use the new one. Note that this
353 // can potentially cause recursive merging.
354 NodeUpdateListener NUL(*this);
355 DAG.ReplaceAllUsesOfValueWith(From, To, &NUL);
357 // The old node may still be present in a map like ExpandedIntegers or
358 // PromotedIntegers. Inform maps about the replacement.
359 ReplacedValues[From] = To;
362 /// ReplaceNodeWith - Replace uses of the 'from' node's results with the 'to'
363 /// node's results. The from and to node must define identical result types.
364 void DAGTypeLegalizer::ReplaceNodeWith(SDNode *From, SDNode *To) {
365 if (From == To) return;
367 // If expansion produced new nodes, make sure they are properly marked.
370 To = AnalyzeNewNode(To); // Expunges To.
371 // If To morphed into an already processed node, its values may need
372 // remapping. This is done below.
374 assert(From->getNumValues() == To->getNumValues() &&
375 "Node results don't match");
377 // Anything that used the old node should now use the new one. Note that this
378 // can potentially cause recursive merging.
379 NodeUpdateListener NUL(*this);
380 for (unsigned i = 0, e = From->getNumValues(); i != e; ++i) {
381 SDValue FromVal(From, i);
382 SDValue ToVal(To, i);
384 // AnalyzeNewNode may have morphed a new node into a processed node. Remap
386 if (To->getNodeId() == Processed)
389 assert(FromVal.getValueType() == ToVal.getValueType() &&
390 "Node results don't match!");
392 // Make anything that used the old value use the new value.
393 DAG.ReplaceAllUsesOfValueWith(FromVal, ToVal, &NUL);
395 // The old node may still be present in a map like ExpandedIntegers or
396 // PromotedIntegers. Inform maps about the replacement.
397 ReplacedValues[FromVal] = ToVal;
401 /// RemapValue - If the specified value was already legalized to another value,
402 /// replace it by that value.
403 void DAGTypeLegalizer::RemapValue(SDValue &N) {
404 DenseMap<SDValue, SDValue>::iterator I = ReplacedValues.find(N);
405 if (I != ReplacedValues.end()) {
406 // Use path compression to speed up future lookups if values get multiply
407 // replaced with other values.
408 RemapValue(I->second);
411 assert(N.getNode()->getNodeId() != NewNode && "Mapped to unanalyzed node!");
414 /// ExpungeNode - If N has a bogus mapping in ReplacedValues, eliminate it.
415 /// This can occur when a node is deleted then reallocated as a new node -
416 /// the mapping in ReplacedValues applies to the deleted node, not the new
418 /// The only map that can have a deleted node as a source is ReplacedValues.
419 /// Other maps can have deleted nodes as targets, but since their looked-up
420 /// values are always immediately remapped using RemapValue, resulting in a
421 /// not-deleted node, this is harmless as long as ReplacedValues/RemapValue
422 /// always performs correct mappings. In order to keep the mapping correct,
423 /// ExpungeNode should be called on any new nodes *before* adding them as
424 /// either source or target to ReplacedValues (which typically means calling
425 /// Expunge when a new node is first seen, since it may no longer be marked
426 /// NewNode by the time it is added to ReplacedValues).
427 void DAGTypeLegalizer::ExpungeNode(SDNode *N) {
428 if (N->getNodeId() != NewNode)
431 // If N is not remapped by ReplacedValues then there is nothing to do.
433 for (i = 0, e = N->getNumValues(); i != e; ++i)
434 if (ReplacedValues.find(SDValue(N, i)) != ReplacedValues.end())
440 // Remove N from all maps - this is expensive but rare.
442 for (DenseMap<SDValue, SDValue>::iterator I = PromotedIntegers.begin(),
443 E = PromotedIntegers.end(); I != E; ++I) {
444 assert(I->first.getNode() != N);
445 RemapValue(I->second);
448 for (DenseMap<SDValue, SDValue>::iterator I = SoftenedFloats.begin(),
449 E = SoftenedFloats.end(); I != E; ++I) {
450 assert(I->first.getNode() != N);
451 RemapValue(I->second);
454 for (DenseMap<SDValue, SDValue>::iterator I = ScalarizedVectors.begin(),
455 E = ScalarizedVectors.end(); I != E; ++I) {
456 assert(I->first.getNode() != N);
457 RemapValue(I->second);
460 for (DenseMap<SDValue, std::pair<SDValue, SDValue> >::iterator
461 I = ExpandedIntegers.begin(), E = ExpandedIntegers.end(); I != E; ++I){
462 assert(I->first.getNode() != N);
463 RemapValue(I->second.first);
464 RemapValue(I->second.second);
467 for (DenseMap<SDValue, std::pair<SDValue, SDValue> >::iterator
468 I = ExpandedFloats.begin(), E = ExpandedFloats.end(); I != E; ++I) {
469 assert(I->first.getNode() != N);
470 RemapValue(I->second.first);
471 RemapValue(I->second.second);
474 for (DenseMap<SDValue, std::pair<SDValue, SDValue> >::iterator
475 I = SplitVectors.begin(), E = SplitVectors.end(); I != E; ++I) {
476 assert(I->first.getNode() != N);
477 RemapValue(I->second.first);
478 RemapValue(I->second.second);
481 for (DenseMap<SDValue, SDValue>::iterator I = ReplacedValues.begin(),
482 E = ReplacedValues.end(); I != E; ++I)
483 RemapValue(I->second);
485 for (unsigned i = 0, e = N->getNumValues(); i != e; ++i)
486 ReplacedValues.erase(SDValue(N, i));
489 void DAGTypeLegalizer::SetPromotedInteger(SDValue Op, SDValue Result) {
490 AnalyzeNewValue(Result);
492 SDValue &OpEntry = PromotedIntegers[Op];
493 assert(OpEntry.getNode() == 0 && "Node is already promoted!");
497 void DAGTypeLegalizer::SetSoftenedFloat(SDValue Op, SDValue Result) {
498 AnalyzeNewValue(Result);
500 SDValue &OpEntry = SoftenedFloats[Op];
501 assert(OpEntry.getNode() == 0 && "Node is already converted to integer!");
505 void DAGTypeLegalizer::SetScalarizedVector(SDValue Op, SDValue Result) {
506 AnalyzeNewValue(Result);
508 SDValue &OpEntry = ScalarizedVectors[Op];
509 assert(OpEntry.getNode() == 0 && "Node is already scalarized!");
513 void DAGTypeLegalizer::GetExpandedInteger(SDValue Op, SDValue &Lo,
515 std::pair<SDValue, SDValue> &Entry = ExpandedIntegers[Op];
516 RemapValue(Entry.first);
517 RemapValue(Entry.second);
518 assert(Entry.first.getNode() && "Operand isn't expanded");
523 void DAGTypeLegalizer::SetExpandedInteger(SDValue Op, SDValue Lo,
525 // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant.
529 // Remember that this is the result of the node.
530 std::pair<SDValue, SDValue> &Entry = ExpandedIntegers[Op];
531 assert(Entry.first.getNode() == 0 && "Node already expanded");
536 void DAGTypeLegalizer::GetExpandedFloat(SDValue Op, SDValue &Lo,
538 std::pair<SDValue, SDValue> &Entry = ExpandedFloats[Op];
539 RemapValue(Entry.first);
540 RemapValue(Entry.second);
541 assert(Entry.first.getNode() && "Operand isn't expanded");
546 void DAGTypeLegalizer::SetExpandedFloat(SDValue Op, SDValue Lo,
548 // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant.
552 // Remember that this is the result of the node.
553 std::pair<SDValue, SDValue> &Entry = ExpandedFloats[Op];
554 assert(Entry.first.getNode() == 0 && "Node already expanded");
559 void DAGTypeLegalizer::GetSplitVector(SDValue Op, SDValue &Lo,
561 std::pair<SDValue, SDValue> &Entry = SplitVectors[Op];
562 RemapValue(Entry.first);
563 RemapValue(Entry.second);
564 assert(Entry.first.getNode() && "Operand isn't split");
569 void DAGTypeLegalizer::SetSplitVector(SDValue Op, SDValue Lo,
571 // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant.
575 // Remember that this is the result of the node.
576 std::pair<SDValue, SDValue> &Entry = SplitVectors[Op];
577 assert(Entry.first.getNode() == 0 && "Node already split");
583 //===----------------------------------------------------------------------===//
585 //===----------------------------------------------------------------------===//
587 /// BitConvertToInteger - Convert to an integer of the same size.
588 SDValue DAGTypeLegalizer::BitConvertToInteger(SDValue Op) {
589 unsigned BitWidth = Op.getValueType().getSizeInBits();
590 return DAG.getNode(ISD::BIT_CONVERT, MVT::getIntegerVT(BitWidth), Op);
593 SDValue DAGTypeLegalizer::CreateStackStoreLoad(SDValue Op,
595 // Create the stack frame object. Make sure it is aligned for both
596 // the source and destination types.
598 TLI.getTargetData()->getPrefTypeAlignment(Op.getValueType().getTypeForMVT());
599 SDValue FIPtr = DAG.CreateStackTemporary(DestVT, SrcAlign);
601 // Emit a store to the stack slot.
602 SDValue Store = DAG.getStore(DAG.getEntryNode(), Op, FIPtr, NULL, 0);
603 // Result is a load from the stack slot.
604 return DAG.getLoad(DestVT, Store, FIPtr, NULL, 0);
607 /// JoinIntegers - Build an integer with low bits Lo and high bits Hi.
608 SDValue DAGTypeLegalizer::JoinIntegers(SDValue Lo, SDValue Hi) {
609 MVT LVT = Lo.getValueType();
610 MVT HVT = Hi.getValueType();
611 MVT NVT = MVT::getIntegerVT(LVT.getSizeInBits() + HVT.getSizeInBits());
613 Lo = DAG.getNode(ISD::ZERO_EXTEND, NVT, Lo);
614 Hi = DAG.getNode(ISD::ANY_EXTEND, NVT, Hi);
615 Hi = DAG.getNode(ISD::SHL, NVT, Hi, DAG.getConstant(LVT.getSizeInBits(),
616 TLI.getShiftAmountTy()));
617 return DAG.getNode(ISD::OR, NVT, Lo, Hi);
620 /// SplitInteger - Return the lower LoVT bits of Op in Lo and the upper HiVT
622 void DAGTypeLegalizer::SplitInteger(SDValue Op,
624 SDValue &Lo, SDValue &Hi) {
625 assert(LoVT.getSizeInBits() + HiVT.getSizeInBits() ==
626 Op.getValueType().getSizeInBits() && "Invalid integer splitting!");
627 Lo = DAG.getNode(ISD::TRUNCATE, LoVT, Op);
628 Hi = DAG.getNode(ISD::SRL, Op.getValueType(), Op,
629 DAG.getConstant(LoVT.getSizeInBits(),
630 TLI.getShiftAmountTy()));
631 Hi = DAG.getNode(ISD::TRUNCATE, HiVT, Hi);
634 /// SplitInteger - Return the lower and upper halves of Op's bits in a value
635 /// type half the size of Op's.
636 void DAGTypeLegalizer::SplitInteger(SDValue Op,
637 SDValue &Lo, SDValue &Hi) {
638 MVT HalfVT = MVT::getIntegerVT(Op.getValueType().getSizeInBits()/2);
639 SplitInteger(Op, HalfVT, HalfVT, Lo, Hi);
642 /// MakeLibCall - Generate a libcall taking the given operands as arguments and
643 /// returning a result of type RetVT.
644 SDValue DAGTypeLegalizer::MakeLibCall(RTLIB::Libcall LC, MVT RetVT,
645 const SDValue *Ops, unsigned NumOps,
647 TargetLowering::ArgListTy Args;
648 Args.reserve(NumOps);
650 TargetLowering::ArgListEntry Entry;
651 for (unsigned i = 0; i != NumOps; ++i) {
653 Entry.Ty = Entry.Node.getValueType().getTypeForMVT();
654 Entry.isSExt = isSigned;
655 Entry.isZExt = !isSigned;
656 Args.push_back(Entry);
658 SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
661 const Type *RetTy = RetVT.getTypeForMVT();
662 std::pair<SDValue,SDValue> CallInfo =
663 TLI.LowerCallTo(DAG.getEntryNode(), RetTy, isSigned, !isSigned, false,
664 false, CallingConv::C, false, Callee, Args, DAG);
665 return CallInfo.first;
668 /// LibCallify - Convert the node into a libcall with the same prototype.
669 SDValue DAGTypeLegalizer::LibCallify(RTLIB::Libcall LC, SDNode *N,
671 unsigned NumOps = N->getNumOperands();
673 return MakeLibCall(LC, N->getValueType(0), 0, 0, isSigned);
674 } else if (NumOps == 1) {
675 SDValue Op = N->getOperand(0);
676 return MakeLibCall(LC, N->getValueType(0), &Op, 1, isSigned);
677 } else if (NumOps == 2) {
678 SDValue Ops[2] = { N->getOperand(0), N->getOperand(1) };
679 return MakeLibCall(LC, N->getValueType(0), Ops, 2, isSigned);
681 SmallVector<SDValue, 8> Ops(NumOps);
682 for (unsigned i = 0; i < NumOps; ++i)
683 Ops[i] = N->getOperand(i);
685 return MakeLibCall(LC, N->getValueType(0), &Ops[0], NumOps, isSigned);
688 SDValue DAGTypeLegalizer::GetVectorElementPointer(SDValue VecPtr, MVT EltVT,
690 // Make sure the index type is big enough to compute in.
691 if (Index.getValueType().bitsGT(TLI.getPointerTy()))
692 Index = DAG.getNode(ISD::TRUNCATE, TLI.getPointerTy(), Index);
694 Index = DAG.getNode(ISD::ZERO_EXTEND, TLI.getPointerTy(), Index);
696 // Calculate the element offset and add it to the pointer.
697 unsigned EltSize = EltVT.getSizeInBits() / 8; // FIXME: should be ABI size.
699 Index = DAG.getNode(ISD::MUL, Index.getValueType(), Index,
700 DAG.getConstant(EltSize, Index.getValueType()));
701 return DAG.getNode(ISD::ADD, Index.getValueType(), Index, VecPtr);
704 /// GetSplitDestVTs - Compute the VTs needed for the low/hi parts of a type
705 /// which is split into two not necessarily identical pieces.
706 void DAGTypeLegalizer::GetSplitDestVTs(MVT InVT, MVT &LoVT, MVT &HiVT) {
707 if (!InVT.isVector()) {
708 LoVT = HiVT = TLI.getTypeToTransformTo(InVT);
710 MVT NewEltVT = InVT.getVectorElementType();
711 unsigned NumElements = InVT.getVectorNumElements();
712 if ((NumElements & (NumElements-1)) == 0) { // Simple power of two vector.
714 LoVT = HiVT = MVT::getVectorVT(NewEltVT, NumElements);
715 } else { // Non-power-of-two vectors.
716 unsigned NewNumElts_Lo = 1 << Log2_32(NumElements);
717 unsigned NewNumElts_Hi = NumElements - NewNumElts_Lo;
718 LoVT = MVT::getVectorVT(NewEltVT, NewNumElts_Lo);
719 HiVT = MVT::getVectorVT(NewEltVT, NewNumElts_Hi);
725 //===----------------------------------------------------------------------===//
727 //===----------------------------------------------------------------------===//
729 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
730 /// only uses types natively supported by the target.
732 /// Note that this is an involved process that may invalidate pointers into
734 void SelectionDAG::LegalizeTypes() {
735 DAGTypeLegalizer(*this).run();