1 //===- DAGISelEmitter.cpp - Generate an instruction selector --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Chris Lattner and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This tablegen backend emits a DAG instruction selector.
12 //===----------------------------------------------------------------------===//
14 #include "DAGISelEmitter.h"
16 #include "llvm/ADT/StringExtras.h"
17 #include "llvm/Support/Debug.h"
22 //===----------------------------------------------------------------------===//
23 // Helpers for working with extended types.
25 /// FilterVTs - Filter a list of VT's according to a predicate.
28 static std::vector<MVT::ValueType>
29 FilterVTs(const std::vector<MVT::ValueType> &InVTs, T Filter) {
30 std::vector<MVT::ValueType> Result;
31 for (unsigned i = 0, e = InVTs.size(); i != e; ++i)
33 Result.push_back(InVTs[i]);
37 /// isExtIntegerVT - Return true if the specified extended value type is
38 /// integer, or isInt.
39 static bool isExtIntegerVT(unsigned char VT) {
40 return VT == MVT::isInt ||
41 (VT < MVT::LAST_VALUETYPE && MVT::isInteger((MVT::ValueType)VT));
44 /// isExtFloatingPointVT - Return true if the specified extended value type is
45 /// floating point, or isFP.
46 static bool isExtFloatingPointVT(unsigned char VT) {
47 return VT == MVT::isFP ||
48 (VT < MVT::LAST_VALUETYPE && MVT::isFloatingPoint((MVT::ValueType)VT));
51 //===----------------------------------------------------------------------===//
52 // SDTypeConstraint implementation
55 SDTypeConstraint::SDTypeConstraint(Record *R) {
56 OperandNo = R->getValueAsInt("OperandNum");
58 if (R->isSubClassOf("SDTCisVT")) {
59 ConstraintType = SDTCisVT;
60 x.SDTCisVT_Info.VT = getValueType(R->getValueAsDef("VT"));
61 } else if (R->isSubClassOf("SDTCisInt")) {
62 ConstraintType = SDTCisInt;
63 } else if (R->isSubClassOf("SDTCisFP")) {
64 ConstraintType = SDTCisFP;
65 } else if (R->isSubClassOf("SDTCisSameAs")) {
66 ConstraintType = SDTCisSameAs;
67 x.SDTCisSameAs_Info.OtherOperandNum = R->getValueAsInt("OtherOperandNum");
68 } else if (R->isSubClassOf("SDTCisVTSmallerThanOp")) {
69 ConstraintType = SDTCisVTSmallerThanOp;
70 x.SDTCisVTSmallerThanOp_Info.OtherOperandNum =
71 R->getValueAsInt("OtherOperandNum");
72 } else if (R->isSubClassOf("SDTCisOpSmallerThanOp")) {
73 ConstraintType = SDTCisOpSmallerThanOp;
74 x.SDTCisOpSmallerThanOp_Info.BigOperandNum =
75 R->getValueAsInt("BigOperandNum");
77 std::cerr << "Unrecognized SDTypeConstraint '" << R->getName() << "'!\n";
82 /// getOperandNum - Return the node corresponding to operand #OpNo in tree
83 /// N, which has NumResults results.
84 TreePatternNode *SDTypeConstraint::getOperandNum(unsigned OpNo,
86 unsigned NumResults) const {
87 assert(NumResults == 1 && "We only work with single result nodes so far!");
89 if (OpNo < NumResults)
90 return N; // FIXME: need value #
92 return N->getChild(OpNo-NumResults);
95 /// ApplyTypeConstraint - Given a node in a pattern, apply this type
96 /// constraint to the nodes operands. This returns true if it makes a
97 /// change, false otherwise. If a type contradiction is found, throw an
99 bool SDTypeConstraint::ApplyTypeConstraint(TreePatternNode *N,
100 const SDNodeInfo &NodeInfo,
101 TreePattern &TP) const {
102 unsigned NumResults = NodeInfo.getNumResults();
103 assert(NumResults == 1 && "We only work with single result nodes so far!");
105 // Check that the number of operands is sane.
106 if (NodeInfo.getNumOperands() >= 0) {
107 if (N->getNumChildren() != (unsigned)NodeInfo.getNumOperands())
108 TP.error(N->getOperator()->getName() + " node requires exactly " +
109 itostr(NodeInfo.getNumOperands()) + " operands!");
112 const CodeGenTarget &CGT = TP.getDAGISelEmitter().getTargetInfo();
114 TreePatternNode *NodeToApply = getOperandNum(OperandNo, N, NumResults);
116 switch (ConstraintType) {
117 default: assert(0 && "Unknown constraint type!");
119 // Operand must be a particular type.
120 return NodeToApply->UpdateNodeType(x.SDTCisVT_Info.VT, TP);
122 // If there is only one integer type supported, this must be it.
123 std::vector<MVT::ValueType> IntVTs =
124 FilterVTs(CGT.getLegalValueTypes(), MVT::isInteger);
126 // If we found exactly one supported integer type, apply it.
127 if (IntVTs.size() == 1)
128 return NodeToApply->UpdateNodeType(IntVTs[0], TP);
129 return NodeToApply->UpdateNodeType(MVT::isInt, TP);
132 // If there is only one FP type supported, this must be it.
133 std::vector<MVT::ValueType> FPVTs =
134 FilterVTs(CGT.getLegalValueTypes(), MVT::isFloatingPoint);
136 // If we found exactly one supported FP type, apply it.
137 if (FPVTs.size() == 1)
138 return NodeToApply->UpdateNodeType(FPVTs[0], TP);
139 return NodeToApply->UpdateNodeType(MVT::isFP, TP);
142 TreePatternNode *OtherNode =
143 getOperandNum(x.SDTCisSameAs_Info.OtherOperandNum, N, NumResults);
144 return NodeToApply->UpdateNodeType(OtherNode->getExtType(), TP) |
145 OtherNode->UpdateNodeType(NodeToApply->getExtType(), TP);
147 case SDTCisVTSmallerThanOp: {
148 // The NodeToApply must be a leaf node that is a VT. OtherOperandNum must
149 // have an integer type that is smaller than the VT.
150 if (!NodeToApply->isLeaf() ||
151 !dynamic_cast<DefInit*>(NodeToApply->getLeafValue()) ||
152 !static_cast<DefInit*>(NodeToApply->getLeafValue())->getDef()
153 ->isSubClassOf("ValueType"))
154 TP.error(N->getOperator()->getName() + " expects a VT operand!");
156 getValueType(static_cast<DefInit*>(NodeToApply->getLeafValue())->getDef());
157 if (!MVT::isInteger(VT))
158 TP.error(N->getOperator()->getName() + " VT operand must be integer!");
160 TreePatternNode *OtherNode =
161 getOperandNum(x.SDTCisVTSmallerThanOp_Info.OtherOperandNum, N,NumResults);
163 // It must be integer.
164 bool MadeChange = false;
165 MadeChange |= OtherNode->UpdateNodeType(MVT::isInt, TP);
167 if (OtherNode->hasTypeSet() && OtherNode->getType() <= VT)
168 OtherNode->UpdateNodeType(MVT::Other, TP); // Throw an error.
171 case SDTCisOpSmallerThanOp: {
172 TreePatternNode *BigOperand =
173 getOperandNum(x.SDTCisOpSmallerThanOp_Info.BigOperandNum, N, NumResults);
175 // Both operands must be integer or FP, but we don't care which.
176 bool MadeChange = false;
178 if (isExtIntegerVT(NodeToApply->getExtType()))
179 MadeChange |= BigOperand->UpdateNodeType(MVT::isInt, TP);
180 else if (isExtFloatingPointVT(NodeToApply->getExtType()))
181 MadeChange |= BigOperand->UpdateNodeType(MVT::isFP, TP);
182 if (isExtIntegerVT(BigOperand->getExtType()))
183 MadeChange |= NodeToApply->UpdateNodeType(MVT::isInt, TP);
184 else if (isExtFloatingPointVT(BigOperand->getExtType()))
185 MadeChange |= NodeToApply->UpdateNodeType(MVT::isFP, TP);
187 std::vector<MVT::ValueType> VTs = CGT.getLegalValueTypes();
189 if (isExtIntegerVT(NodeToApply->getExtType())) {
190 VTs = FilterVTs(VTs, MVT::isInteger);
191 } else if (isExtFloatingPointVT(NodeToApply->getExtType())) {
192 VTs = FilterVTs(VTs, MVT::isFloatingPoint);
197 switch (VTs.size()) {
198 default: // Too many VT's to pick from.
199 case 0: break; // No info yet.
201 // Only one VT of this flavor. Cannot ever satisify the constraints.
202 return NodeToApply->UpdateNodeType(MVT::Other, TP); // throw
204 // If we have exactly two possible types, the little operand must be the
205 // small one, the big operand should be the big one. Common with
206 // float/double for example.
207 assert(VTs[0] < VTs[1] && "Should be sorted!");
208 MadeChange |= NodeToApply->UpdateNodeType(VTs[0], TP);
209 MadeChange |= BigOperand->UpdateNodeType(VTs[1], TP);
219 //===----------------------------------------------------------------------===//
220 // SDNodeInfo implementation
222 SDNodeInfo::SDNodeInfo(Record *R) : Def(R) {
223 EnumName = R->getValueAsString("Opcode");
224 SDClassName = R->getValueAsString("SDClass");
225 Record *TypeProfile = R->getValueAsDef("TypeProfile");
226 NumResults = TypeProfile->getValueAsInt("NumResults");
227 NumOperands = TypeProfile->getValueAsInt("NumOperands");
229 // Parse the properties.
231 ListInit *LI = R->getValueAsListInit("Properties");
232 for (unsigned i = 0, e = LI->getSize(); i != e; ++i) {
233 DefInit *DI = dynamic_cast<DefInit*>(LI->getElement(i));
234 assert(DI && "Properties list must be list of defs!");
235 if (DI->getDef()->getName() == "SDNPCommutative") {
236 Properties |= 1 << SDNPCommutative;
237 } else if (DI->getDef()->getName() == "SDNPAssociative") {
238 Properties |= 1 << SDNPAssociative;
240 std::cerr << "Unknown SD Node property '" << DI->getDef()->getName()
241 << "' on node '" << R->getName() << "'!\n";
247 // Parse the type constraints.
248 ListInit *Constraints = TypeProfile->getValueAsListInit("Constraints");
249 for (unsigned i = 0, e = Constraints->getSize(); i != e; ++i) {
250 assert(dynamic_cast<DefInit*>(Constraints->getElement(i)) &&
251 "Constraints list should contain constraint definitions!");
253 static_cast<DefInit*>(Constraints->getElement(i))->getDef();
254 TypeConstraints.push_back(Constraint);
258 //===----------------------------------------------------------------------===//
259 // TreePatternNode implementation
262 TreePatternNode::~TreePatternNode() {
263 #if 0 // FIXME: implement refcounted tree nodes!
264 for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
269 /// UpdateNodeType - Set the node type of N to VT if VT contains
270 /// information. If N already contains a conflicting type, then throw an
271 /// exception. This returns true if any information was updated.
273 bool TreePatternNode::UpdateNodeType(unsigned char VT, TreePattern &TP) {
274 if (VT == MVT::isUnknown || getExtType() == VT) return false;
275 if (getExtType() == MVT::isUnknown) {
280 // If we are told this is to be an int or FP type, and it already is, ignore
282 if ((VT == MVT::isInt && isExtIntegerVT(getExtType())) ||
283 (VT == MVT::isFP && isExtFloatingPointVT(getExtType())))
286 // If we know this is an int or fp type, and we are told it is a specific one,
288 if ((getExtType() == MVT::isInt && isExtIntegerVT(VT)) ||
289 (getExtType() == MVT::isFP && isExtFloatingPointVT(VT))) {
294 TP.error("Type inference contradiction found in node " +
295 getOperator()->getName() + "!");
296 return true; // unreachable
300 void TreePatternNode::print(std::ostream &OS) const {
302 OS << *getLeafValue();
304 OS << "(" << getOperator()->getName();
307 switch (getExtType()) {
308 case MVT::Other: OS << ":Other"; break;
309 case MVT::isInt: OS << ":isInt"; break;
310 case MVT::isFP : OS << ":isFP"; break;
311 case MVT::isUnknown: ; /*OS << ":?";*/ break;
312 default: OS << ":" << getType(); break;
316 if (getNumChildren() != 0) {
318 getChild(0)->print(OS);
319 for (unsigned i = 1, e = getNumChildren(); i != e; ++i) {
321 getChild(i)->print(OS);
327 if (!PredicateFn.empty())
328 OS << "<<P:" << PredicateFn << ">>";
330 OS << "<<X:" << TransformFn->getName() << ">>";
331 if (!getName().empty())
332 OS << ":$" << getName();
335 void TreePatternNode::dump() const {
339 /// isIsomorphicTo - Return true if this node is recursively isomorphic to
340 /// the specified node. For this comparison, all of the state of the node
341 /// is considered, except for the assigned name. Nodes with differing names
342 /// that are otherwise identical are considered isomorphic.
343 bool TreePatternNode::isIsomorphicTo(const TreePatternNode *N) const {
344 if (N == this) return true;
345 if (N->isLeaf() != isLeaf() || getExtType() != N->getExtType() ||
346 getPredicateFn() != N->getPredicateFn() ||
347 getTransformFn() != N->getTransformFn())
351 if (DefInit *DI = dynamic_cast<DefInit*>(getLeafValue()))
352 if (DefInit *NDI = dynamic_cast<DefInit*>(N->getLeafValue()))
353 return DI->getDef() == NDI->getDef();
354 return getLeafValue() == N->getLeafValue();
357 if (N->getOperator() != getOperator() ||
358 N->getNumChildren() != getNumChildren()) return false;
359 for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
360 if (!getChild(i)->isIsomorphicTo(N->getChild(i)))
365 /// clone - Make a copy of this tree and all of its children.
367 TreePatternNode *TreePatternNode::clone() const {
368 TreePatternNode *New;
370 New = new TreePatternNode(getLeafValue());
372 std::vector<TreePatternNode*> CChildren;
373 CChildren.reserve(Children.size());
374 for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
375 CChildren.push_back(getChild(i)->clone());
376 New = new TreePatternNode(getOperator(), CChildren);
378 New->setName(getName());
379 New->setType(getExtType());
380 New->setPredicateFn(getPredicateFn());
381 New->setTransformFn(getTransformFn());
385 /// SubstituteFormalArguments - Replace the formal arguments in this tree
386 /// with actual values specified by ArgMap.
387 void TreePatternNode::
388 SubstituteFormalArguments(std::map<std::string, TreePatternNode*> &ArgMap) {
389 if (isLeaf()) return;
391 for (unsigned i = 0, e = getNumChildren(); i != e; ++i) {
392 TreePatternNode *Child = getChild(i);
393 if (Child->isLeaf()) {
394 Init *Val = Child->getLeafValue();
395 if (dynamic_cast<DefInit*>(Val) &&
396 static_cast<DefInit*>(Val)->getDef()->getName() == "node") {
397 // We found a use of a formal argument, replace it with its value.
398 Child = ArgMap[Child->getName()];
399 assert(Child && "Couldn't find formal argument!");
403 getChild(i)->SubstituteFormalArguments(ArgMap);
409 /// InlinePatternFragments - If this pattern refers to any pattern
410 /// fragments, inline them into place, giving us a pattern without any
411 /// PatFrag references.
412 TreePatternNode *TreePatternNode::InlinePatternFragments(TreePattern &TP) {
413 if (isLeaf()) return this; // nothing to do.
414 Record *Op = getOperator();
416 if (!Op->isSubClassOf("PatFrag")) {
417 // Just recursively inline children nodes.
418 for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
419 setChild(i, getChild(i)->InlinePatternFragments(TP));
423 // Otherwise, we found a reference to a fragment. First, look up its
424 // TreePattern record.
425 TreePattern *Frag = TP.getDAGISelEmitter().getPatternFragment(Op);
427 // Verify that we are passing the right number of operands.
428 if (Frag->getNumArgs() != Children.size())
429 TP.error("'" + Op->getName() + "' fragment requires " +
430 utostr(Frag->getNumArgs()) + " operands!");
432 TreePatternNode *FragTree = Frag->getOnlyTree()->clone();
434 // Resolve formal arguments to their actual value.
435 if (Frag->getNumArgs()) {
436 // Compute the map of formal to actual arguments.
437 std::map<std::string, TreePatternNode*> ArgMap;
438 for (unsigned i = 0, e = Frag->getNumArgs(); i != e; ++i)
439 ArgMap[Frag->getArgName(i)] = getChild(i)->InlinePatternFragments(TP);
441 FragTree->SubstituteFormalArguments(ArgMap);
444 FragTree->setName(getName());
446 // Get a new copy of this fragment to stitch into here.
447 //delete this; // FIXME: implement refcounting!
451 /// getIntrinsicType - Check to see if the specified record has an intrinsic
452 /// type which should be applied to it. This infer the type of register
453 /// references from the register file information, for example.
455 static unsigned char getIntrinsicType(Record *R, bool NotRegisters,
457 // Check to see if this is a register or a register class...
458 if (R->isSubClassOf("RegisterClass")) {
459 if (NotRegisters) return MVT::isUnknown;
460 return getValueType(R->getValueAsDef("RegType"));
461 } else if (R->isSubClassOf("PatFrag")) {
462 // Pattern fragment types will be resolved when they are inlined.
463 return MVT::isUnknown;
464 } else if (R->isSubClassOf("Register")) {
465 assert(0 && "Explicit registers not handled here yet!\n");
466 return MVT::isUnknown;
467 } else if (R->isSubClassOf("ValueType")) {
470 } else if (R->getName() == "node") {
472 return MVT::isUnknown;
475 TP.error("Unknown node flavor used in pattern: " + R->getName());
479 /// ApplyTypeConstraints - Apply all of the type constraints relevent to
480 /// this node and its children in the tree. This returns true if it makes a
481 /// change, false otherwise. If a type contradiction is found, throw an
483 bool TreePatternNode::ApplyTypeConstraints(TreePattern &TP, bool NotRegisters) {
485 if (DefInit *DI = dynamic_cast<DefInit*>(getLeafValue()))
486 // If it's a regclass or something else known, include the type.
487 return UpdateNodeType(getIntrinsicType(DI->getDef(), NotRegisters, TP),
492 // special handling for set, which isn't really an SDNode.
493 if (getOperator()->getName() == "set") {
494 assert (getNumChildren() == 2 && "Only handle 2 operand set's for now!");
495 bool MadeChange = getChild(0)->ApplyTypeConstraints(TP, NotRegisters);
496 MadeChange |= getChild(1)->ApplyTypeConstraints(TP, NotRegisters);
498 // Types of operands must match.
499 MadeChange |= getChild(0)->UpdateNodeType(getChild(1)->getExtType(), TP);
500 MadeChange |= getChild(1)->UpdateNodeType(getChild(0)->getExtType(), TP);
501 MadeChange |= UpdateNodeType(MVT::isVoid, TP);
503 } else if (getOperator()->isSubClassOf("SDNode")) {
504 const SDNodeInfo &NI = TP.getDAGISelEmitter().getSDNodeInfo(getOperator());
506 bool MadeChange = NI.ApplyTypeConstraints(this, TP);
507 for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
508 MadeChange |= getChild(i)->ApplyTypeConstraints(TP, NotRegisters);
510 } else if (getOperator()->isSubClassOf("Instruction")) {
511 const DAGInstruction &Inst =
512 TP.getDAGISelEmitter().getInstruction(getOperator());
514 assert(Inst.getNumResults() == 1 && "Only supports one result instrs!");
515 // Apply the result type to the node
516 bool MadeChange = UpdateNodeType(Inst.getResultType(0), TP);
518 if (getNumChildren() != Inst.getNumOperands())
519 TP.error("Instruction '" + getOperator()->getName() + " expects " +
520 utostr(Inst.getNumOperands()) + " operands, not " +
521 utostr(getNumChildren()) + " operands!");
522 for (unsigned i = 0, e = getNumChildren(); i != e; ++i) {
523 MadeChange |= getChild(i)->UpdateNodeType(Inst.getOperandType(i), TP);
524 MadeChange |= getChild(i)->ApplyTypeConstraints(TP, NotRegisters);
528 assert(getOperator()->isSubClassOf("SDNodeXForm") && "Unknown node type!");
530 // Node transforms always take one operand, and take and return the same
532 if (getNumChildren() != 1)
533 TP.error("Node transform '" + getOperator()->getName() +
534 "' requires one operand!");
535 bool MadeChange = UpdateNodeType(getChild(0)->getExtType(), TP);
536 MadeChange |= getChild(0)->UpdateNodeType(getExtType(), TP);
541 /// canPatternMatch - If it is impossible for this pattern to match on this
542 /// target, fill in Reason and return false. Otherwise, return true. This is
543 /// used as a santity check for .td files (to prevent people from writing stuff
544 /// that can never possibly work), and to prevent the pattern permuter from
545 /// generating stuff that is useless.
546 bool TreePatternNode::canPatternMatch(std::string &Reason, DAGISelEmitter &ISE){
547 if (isLeaf()) return true;
549 for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
550 if (!getChild(i)->canPatternMatch(Reason, ISE))
553 // If this node is a commutative operator, check that the LHS isn't an
555 const SDNodeInfo &NodeInfo = ISE.getSDNodeInfo(getOperator());
556 if (NodeInfo.hasProperty(SDNodeInfo::SDNPCommutative)) {
557 // Scan all of the operands of the node and make sure that only the last one
558 // is a constant node.
559 for (unsigned i = 0, e = getNumChildren()-1; i != e; ++i)
560 if (!getChild(i)->isLeaf() &&
561 getChild(i)->getOperator()->getName() == "imm") {
562 Reason = "Immediate value must be on the RHS of commutative operators!";
570 //===----------------------------------------------------------------------===//
571 // TreePattern implementation
574 TreePattern::TreePattern(Record *TheRec, ListInit *RawPat,
575 DAGISelEmitter &ise) : TheRecord(TheRec), ISE(ise) {
576 for (unsigned i = 0, e = RawPat->getSize(); i != e; ++i)
577 Trees.push_back(ParseTreePattern((DagInit*)RawPat->getElement(i)));
580 TreePattern::TreePattern(Record *TheRec, DagInit *Pat,
581 DAGISelEmitter &ise) : TheRecord(TheRec), ISE(ise) {
582 Trees.push_back(ParseTreePattern(Pat));
585 TreePattern::TreePattern(Record *TheRec, TreePatternNode *Pat,
586 DAGISelEmitter &ise) : TheRecord(TheRec), ISE(ise) {
587 Trees.push_back(Pat);
592 void TreePattern::error(const std::string &Msg) const {
594 throw "In " + TheRecord->getName() + ": " + Msg;
597 TreePatternNode *TreePattern::ParseTreePattern(DagInit *Dag) {
598 Record *Operator = Dag->getNodeType();
600 if (Operator->isSubClassOf("ValueType")) {
601 // If the operator is a ValueType, then this must be "type cast" of a leaf
603 if (Dag->getNumArgs() != 1)
604 error("Type cast only takes one operand!");
606 Init *Arg = Dag->getArg(0);
607 TreePatternNode *New;
608 if (DefInit *DI = dynamic_cast<DefInit*>(Arg)) {
609 Record *R = DI->getDef();
610 if (R->isSubClassOf("SDNode") || R->isSubClassOf("PatFrag")) {
611 Dag->setArg(0, new DagInit(R,
612 std::vector<std::pair<Init*, std::string> >()));
613 TreePatternNode *TPN = ParseTreePattern(Dag);
614 TPN->setName(Dag->getArgName(0));
618 New = new TreePatternNode(DI);
619 } else if (DagInit *DI = dynamic_cast<DagInit*>(Arg)) {
620 New = ParseTreePattern(DI);
623 error("Unknown leaf value for tree pattern!");
627 // Apply the type cast.
628 New->UpdateNodeType(getValueType(Operator), *this);
632 // Verify that this is something that makes sense for an operator.
633 if (!Operator->isSubClassOf("PatFrag") && !Operator->isSubClassOf("SDNode") &&
634 !Operator->isSubClassOf("Instruction") &&
635 !Operator->isSubClassOf("SDNodeXForm") &&
636 Operator->getName() != "set")
637 error("Unrecognized node '" + Operator->getName() + "'!");
639 std::vector<TreePatternNode*> Children;
641 for (unsigned i = 0, e = Dag->getNumArgs(); i != e; ++i) {
642 Init *Arg = Dag->getArg(i);
643 if (DagInit *DI = dynamic_cast<DagInit*>(Arg)) {
644 Children.push_back(ParseTreePattern(DI));
645 Children.back()->setName(Dag->getArgName(i));
646 } else if (DefInit *DefI = dynamic_cast<DefInit*>(Arg)) {
647 Record *R = DefI->getDef();
648 // Direct reference to a leaf DagNode or PatFrag? Turn it into a
649 // TreePatternNode if its own.
650 if (R->isSubClassOf("SDNode") || R->isSubClassOf("PatFrag")) {
651 Dag->setArg(i, new DagInit(R,
652 std::vector<std::pair<Init*, std::string> >()));
653 --i; // Revisit this node...
655 TreePatternNode *Node = new TreePatternNode(DefI);
656 Node->setName(Dag->getArgName(i));
657 Children.push_back(Node);
660 if (R->getName() == "node") {
661 if (Dag->getArgName(i).empty())
662 error("'node' argument requires a name to match with operand list");
663 Args.push_back(Dag->getArgName(i));
668 error("Unknown leaf value for tree pattern!");
672 return new TreePatternNode(Operator, Children);
675 /// InferAllTypes - Infer/propagate as many types throughout the expression
676 /// patterns as possible. Return true if all types are infered, false
677 /// otherwise. Throw an exception if a type contradiction is found.
678 bool TreePattern::InferAllTypes() {
679 bool MadeChange = true;
682 for (unsigned i = 0, e = Trees.size(); i != e; ++i)
683 MadeChange |= Trees[i]->ApplyTypeConstraints(*this, false);
686 bool HasUnresolvedTypes = false;
687 for (unsigned i = 0, e = Trees.size(); i != e; ++i)
688 HasUnresolvedTypes |= Trees[i]->ContainsUnresolvedType();
689 return !HasUnresolvedTypes;
692 void TreePattern::print(std::ostream &OS) const {
693 OS << getRecord()->getName();
695 OS << "(" << Args[0];
696 for (unsigned i = 1, e = Args.size(); i != e; ++i)
697 OS << ", " << Args[i];
702 if (Trees.size() > 1)
704 for (unsigned i = 0, e = Trees.size(); i != e; ++i) {
710 if (Trees.size() > 1)
714 void TreePattern::dump() const { print(std::cerr); }
718 //===----------------------------------------------------------------------===//
719 // DAGISelEmitter implementation
722 // Parse all of the SDNode definitions for the target, populating SDNodes.
723 void DAGISelEmitter::ParseNodeInfo() {
724 std::vector<Record*> Nodes = Records.getAllDerivedDefinitions("SDNode");
725 while (!Nodes.empty()) {
726 SDNodes.insert(std::make_pair(Nodes.back(), Nodes.back()));
731 /// ParseNodeTransforms - Parse all SDNodeXForm instances into the SDNodeXForms
732 /// map, and emit them to the file as functions.
733 void DAGISelEmitter::ParseNodeTransforms(std::ostream &OS) {
734 OS << "\n// Node transformations.\n";
735 std::vector<Record*> Xforms = Records.getAllDerivedDefinitions("SDNodeXForm");
736 while (!Xforms.empty()) {
737 Record *XFormNode = Xforms.back();
738 Record *SDNode = XFormNode->getValueAsDef("Opcode");
739 std::string Code = XFormNode->getValueAsCode("XFormFunction");
740 SDNodeXForms.insert(std::make_pair(XFormNode,
741 std::make_pair(SDNode, Code)));
744 std::string ClassName = getSDNodeInfo(SDNode).getSDClassName();
745 const char *C2 = ClassName == "SDNode" ? "N" : "inN";
747 OS << "inline SDOperand Transform_" << XFormNode->getName()
748 << "(SDNode *" << C2 << ") {\n";
749 if (ClassName != "SDNode")
750 OS << " " << ClassName << " *N = cast<" << ClassName << ">(inN);\n";
751 OS << Code << "\n}\n";
760 /// ParsePatternFragments - Parse all of the PatFrag definitions in the .td
761 /// file, building up the PatternFragments map. After we've collected them all,
762 /// inline fragments together as necessary, so that there are no references left
763 /// inside a pattern fragment to a pattern fragment.
765 /// This also emits all of the predicate functions to the output file.
767 void DAGISelEmitter::ParsePatternFragments(std::ostream &OS) {
768 std::vector<Record*> Fragments = Records.getAllDerivedDefinitions("PatFrag");
770 // First step, parse all of the fragments and emit predicate functions.
771 OS << "\n// Predicate functions.\n";
772 for (unsigned i = 0, e = Fragments.size(); i != e; ++i) {
773 DagInit *Tree = Fragments[i]->getValueAsDag("Fragment");
774 TreePattern *P = new TreePattern(Fragments[i], Tree, *this);
775 PatternFragments[Fragments[i]] = P;
777 // Validate the argument list, converting it to map, to discard duplicates.
778 std::vector<std::string> &Args = P->getArgList();
779 std::set<std::string> OperandsMap(Args.begin(), Args.end());
781 if (OperandsMap.count(""))
782 P->error("Cannot have unnamed 'node' values in pattern fragment!");
784 // Parse the operands list.
785 DagInit *OpsList = Fragments[i]->getValueAsDag("Operands");
786 if (OpsList->getNodeType()->getName() != "ops")
787 P->error("Operands list should start with '(ops ... '!");
789 // Copy over the arguments.
791 for (unsigned j = 0, e = OpsList->getNumArgs(); j != e; ++j) {
792 if (!dynamic_cast<DefInit*>(OpsList->getArg(j)) ||
793 static_cast<DefInit*>(OpsList->getArg(j))->
794 getDef()->getName() != "node")
795 P->error("Operands list should all be 'node' values.");
796 if (OpsList->getArgName(j).empty())
797 P->error("Operands list should have names for each operand!");
798 if (!OperandsMap.count(OpsList->getArgName(j)))
799 P->error("'" + OpsList->getArgName(j) +
800 "' does not occur in pattern or was multiply specified!");
801 OperandsMap.erase(OpsList->getArgName(j));
802 Args.push_back(OpsList->getArgName(j));
805 if (!OperandsMap.empty())
806 P->error("Operands list does not contain an entry for operand '" +
807 *OperandsMap.begin() + "'!");
809 // If there is a code init for this fragment, emit the predicate code and
810 // keep track of the fact that this fragment uses it.
811 std::string Code = Fragments[i]->getValueAsCode("Predicate");
813 assert(!P->getOnlyTree()->isLeaf() && "Can't be a leaf!");
814 std::string ClassName =
815 getSDNodeInfo(P->getOnlyTree()->getOperator()).getSDClassName();
816 const char *C2 = ClassName == "SDNode" ? "N" : "inN";
818 OS << "inline bool Predicate_" << Fragments[i]->getName()
819 << "(SDNode *" << C2 << ") {\n";
820 if (ClassName != "SDNode")
821 OS << " " << ClassName << " *N = cast<" << ClassName << ">(inN);\n";
822 OS << Code << "\n}\n";
823 P->getOnlyTree()->setPredicateFn("Predicate_"+Fragments[i]->getName());
826 // If there is a node transformation corresponding to this, keep track of
828 Record *Transform = Fragments[i]->getValueAsDef("OperandTransform");
829 if (!getSDNodeTransform(Transform).second.empty()) // not noop xform?
830 P->getOnlyTree()->setTransformFn(Transform);
835 // Now that we've parsed all of the tree fragments, do a closure on them so
836 // that there are not references to PatFrags left inside of them.
837 for (std::map<Record*, TreePattern*>::iterator I = PatternFragments.begin(),
838 E = PatternFragments.end(); I != E; ++I) {
839 TreePattern *ThePat = I->second;
840 ThePat->InlinePatternFragments();
842 // Infer as many types as possible. Don't worry about it if we don't infer
843 // all of them, some may depend on the inputs of the pattern.
845 ThePat->InferAllTypes();
847 // If this pattern fragment is not supported by this target (no types can
848 // satisfy its constraints), just ignore it. If the bogus pattern is
849 // actually used by instructions, the type consistency error will be
853 // If debugging, print out the pattern fragment result.
854 DEBUG(ThePat->dump());
858 /// HandleUse - Given "Pat" a leaf in the pattern, check to see if it is an
859 /// instruction input. Return true if this is a real use.
860 static bool HandleUse(TreePattern *I, TreePatternNode *Pat,
861 std::map<std::string, TreePatternNode*> &InstInputs) {
862 // No name -> not interesting.
863 if (Pat->getName().empty()) {
865 DefInit *DI = dynamic_cast<DefInit*>(Pat->getLeafValue());
866 if (DI && DI->getDef()->isSubClassOf("RegisterClass"))
867 I->error("Input " + DI->getDef()->getName() + " must be named!");
875 DefInit *DI = dynamic_cast<DefInit*>(Pat->getLeafValue());
876 if (!DI) I->error("Input $" + Pat->getName() + " must be an identifier!");
879 assert(Pat->getNumChildren() == 0 && "can't be a use with children!");
880 Rec = Pat->getOperator();
883 TreePatternNode *&Slot = InstInputs[Pat->getName()];
888 if (Slot->isLeaf()) {
889 SlotRec = dynamic_cast<DefInit*>(Slot->getLeafValue())->getDef();
891 assert(Slot->getNumChildren() == 0 && "can't be a use with children!");
892 SlotRec = Slot->getOperator();
895 // Ensure that the inputs agree if we've already seen this input.
897 I->error("All $" + Pat->getName() + " inputs must agree with each other");
898 if (Slot->getExtType() != Pat->getExtType())
899 I->error("All $" + Pat->getName() + " inputs must agree with each other");
904 /// FindPatternInputsAndOutputs - Scan the specified TreePatternNode (which is
905 /// part of "I", the instruction), computing the set of inputs and outputs of
906 /// the pattern. Report errors if we see anything naughty.
907 void DAGISelEmitter::
908 FindPatternInputsAndOutputs(TreePattern *I, TreePatternNode *Pat,
909 std::map<std::string, TreePatternNode*> &InstInputs,
910 std::map<std::string, Record*> &InstResults) {
912 bool isUse = HandleUse(I, Pat, InstInputs);
913 if (!isUse && Pat->getTransformFn())
914 I->error("Cannot specify a transform function for a non-input value!");
916 } else if (Pat->getOperator()->getName() != "set") {
917 // If this is not a set, verify that the children nodes are not void typed,
919 for (unsigned i = 0, e = Pat->getNumChildren(); i != e; ++i) {
920 if (Pat->getChild(i)->getExtType() == MVT::isVoid)
921 I->error("Cannot have void nodes inside of patterns!");
922 FindPatternInputsAndOutputs(I, Pat->getChild(i), InstInputs, InstResults);
925 // If this is a non-leaf node with no children, treat it basically as if
926 // it were a leaf. This handles nodes like (imm).
928 if (Pat->getNumChildren() == 0)
929 isUse = HandleUse(I, Pat, InstInputs);
931 if (!isUse && Pat->getTransformFn())
932 I->error("Cannot specify a transform function for a non-input value!");
936 // Otherwise, this is a set, validate and collect instruction results.
937 if (Pat->getNumChildren() == 0)
938 I->error("set requires operands!");
939 else if (Pat->getNumChildren() & 1)
940 I->error("set requires an even number of operands");
942 if (Pat->getTransformFn())
943 I->error("Cannot specify a transform function on a set node!");
945 // Check the set destinations.
946 unsigned NumValues = Pat->getNumChildren()/2;
947 for (unsigned i = 0; i != NumValues; ++i) {
948 TreePatternNode *Dest = Pat->getChild(i);
950 I->error("set destination should be a virtual register!");
952 DefInit *Val = dynamic_cast<DefInit*>(Dest->getLeafValue());
954 I->error("set destination should be a virtual register!");
956 if (!Val->getDef()->isSubClassOf("RegisterClass"))
957 I->error("set destination should be a virtual register!");
958 if (Dest->getName().empty())
959 I->error("set destination must have a name!");
960 if (InstResults.count(Dest->getName()))
961 I->error("cannot set '" + Dest->getName() +"' multiple times");
962 InstResults[Dest->getName()] = Val->getDef();
964 // Verify and collect info from the computation.
965 FindPatternInputsAndOutputs(I, Pat->getChild(i+NumValues),
966 InstInputs, InstResults);
971 /// ParseInstructions - Parse all of the instructions, inlining and resolving
972 /// any fragments involved. This populates the Instructions list with fully
973 /// resolved instructions.
974 void DAGISelEmitter::ParseInstructions() {
975 std::vector<Record*> Instrs = Records.getAllDerivedDefinitions("Instruction");
977 for (unsigned i = 0, e = Instrs.size(); i != e; ++i) {
978 if (!dynamic_cast<ListInit*>(Instrs[i]->getValueInit("Pattern")))
979 continue; // no pattern yet, ignore it.
981 ListInit *LI = Instrs[i]->getValueAsListInit("Pattern");
982 if (LI->getSize() == 0) continue; // no pattern.
984 // Parse the instruction.
985 TreePattern *I = new TreePattern(Instrs[i], LI, *this);
986 // Inline pattern fragments into it.
987 I->InlinePatternFragments();
989 // Infer as many types as possible. If we cannot infer all of them, we can
990 // never do anything with this instruction pattern: report it to the user.
991 if (!I->InferAllTypes())
992 I->error("Could not infer all types in pattern!");
994 // InstInputs - Keep track of all of the inputs of the instruction, along
995 // with the record they are declared as.
996 std::map<std::string, TreePatternNode*> InstInputs;
998 // InstResults - Keep track of all the virtual registers that are 'set'
999 // in the instruction, including what reg class they are.
1000 std::map<std::string, Record*> InstResults;
1002 // Verify that the top-level forms in the instruction are of void type, and
1003 // fill in the InstResults map.
1004 for (unsigned j = 0, e = I->getNumTrees(); j != e; ++j) {
1005 TreePatternNode *Pat = I->getTree(j);
1006 if (Pat->getExtType() != MVT::isVoid) {
1008 I->error("Top-level forms in instruction pattern should have"
1012 // Find inputs and outputs, and verify the structure of the uses/defs.
1013 FindPatternInputsAndOutputs(I, Pat, InstInputs, InstResults);
1016 // Now that we have inputs and outputs of the pattern, inspect the operands
1017 // list for the instruction. This determines the order that operands are
1018 // added to the machine instruction the node corresponds to.
1019 unsigned NumResults = InstResults.size();
1021 // Parse the operands list from the (ops) list, validating it.
1022 std::vector<std::string> &Args = I->getArgList();
1023 assert(Args.empty() && "Args list should still be empty here!");
1024 CodeGenInstruction &CGI = Target.getInstruction(Instrs[i]->getName());
1026 // Check that all of the results occur first in the list.
1027 std::vector<MVT::ValueType> ResultTypes;
1028 for (unsigned i = 0; i != NumResults; ++i) {
1029 if (i == CGI.OperandList.size())
1030 I->error("'" + InstResults.begin()->first +
1031 "' set but does not appear in operand list!");
1032 const std::string &OpName = CGI.OperandList[i].Name;
1034 // Check that it exists in InstResults.
1035 Record *R = InstResults[OpName];
1037 I->error("Operand $" + OpName + " should be a set destination: all "
1038 "outputs must occur before inputs in operand list!");
1040 if (CGI.OperandList[i].Rec != R)
1041 I->error("Operand $" + OpName + " class mismatch!");
1043 // Remember the return type.
1044 ResultTypes.push_back(CGI.OperandList[i].Ty);
1046 // Okay, this one checks out.
1047 InstResults.erase(OpName);
1050 // Loop over the inputs next. Make a copy of InstInputs so we can destroy
1051 // the copy while we're checking the inputs.
1052 std::map<std::string, TreePatternNode*> InstInputsCheck(InstInputs);
1054 std::vector<TreePatternNode*> ResultNodeOperands;
1055 std::vector<MVT::ValueType> OperandTypes;
1056 for (unsigned i = NumResults, e = CGI.OperandList.size(); i != e; ++i) {
1057 const std::string &OpName = CGI.OperandList[i].Name;
1059 I->error("Operand #" + utostr(i) + " in operands list has no name!");
1061 if (!InstInputsCheck.count(OpName))
1062 I->error("Operand $" + OpName +
1063 " does not appear in the instruction pattern");
1064 TreePatternNode *InVal = InstInputsCheck[OpName];
1065 InstInputsCheck.erase(OpName); // It occurred, remove from map.
1066 if (CGI.OperandList[i].Ty != InVal->getExtType())
1067 I->error("Operand $" + OpName +
1068 "'s type disagrees between the operand and pattern");
1069 OperandTypes.push_back(InVal->getType());
1071 // Construct the result for the dest-pattern operand list.
1072 TreePatternNode *OpNode = InVal->clone();
1074 // No predicate is useful on the result.
1075 OpNode->setPredicateFn("");
1077 // Promote the xform function to be an explicit node if set.
1078 if (Record *Xform = OpNode->getTransformFn()) {
1079 OpNode->setTransformFn(0);
1080 std::vector<TreePatternNode*> Children;
1081 Children.push_back(OpNode);
1082 OpNode = new TreePatternNode(Xform, Children);
1085 ResultNodeOperands.push_back(OpNode);
1088 if (!InstInputsCheck.empty())
1089 I->error("Input operand $" + InstInputsCheck.begin()->first +
1090 " occurs in pattern but not in operands list!");
1092 TreePatternNode *ResultPattern =
1093 new TreePatternNode(I->getRecord(), ResultNodeOperands);
1095 // Create and insert the instruction.
1096 DAGInstruction TheInst(I, ResultTypes, OperandTypes);
1097 Instructions.insert(std::make_pair(I->getRecord(), TheInst));
1099 // Use a temporary tree pattern to infer all types and make sure that the
1100 // constructed result is correct. This depends on the instruction already
1101 // being inserted into the Instructions map.
1102 TreePattern Temp(I->getRecord(), ResultPattern, *this);
1103 Temp.InferAllTypes();
1105 DAGInstruction &TheInsertedInst = Instructions.find(I->getRecord())->second;
1106 TheInsertedInst.setResultPattern(Temp.getOnlyTree());
1111 // If we can, convert the instructions to be patterns that are matched!
1112 for (std::map<Record*, DAGInstruction>::iterator II = Instructions.begin(),
1113 E = Instructions.end(); II != E; ++II) {
1114 TreePattern *I = II->second.getPattern();
1116 if (I->getNumTrees() != 1) {
1117 std::cerr << "CANNOT HANDLE: " << I->getRecord()->getName() << " yet!";
1120 TreePatternNode *Pattern = I->getTree(0);
1121 if (Pattern->getOperator()->getName() != "set")
1122 continue; // Not a set (store or something?)
1124 if (Pattern->getNumChildren() != 2)
1125 continue; // Not a set of a single value (not handled so far)
1127 TreePatternNode *SrcPattern = Pattern->getChild(1)->clone();
1130 if (!SrcPattern->canPatternMatch(Reason, *this))
1131 I->error("Instruction can never match: " + Reason);
1133 TreePatternNode *DstPattern = II->second.getResultPattern();
1134 PatternsToMatch.push_back(std::make_pair(SrcPattern, DstPattern));
1138 void DAGISelEmitter::ParsePatterns() {
1139 std::vector<Record*> Patterns = Records.getAllDerivedDefinitions("Pattern");
1141 for (unsigned i = 0, e = Patterns.size(); i != e; ++i) {
1142 DagInit *Tree = Patterns[i]->getValueAsDag("PatternToMatch");
1143 TreePattern *Pattern = new TreePattern(Patterns[i], Tree, *this);
1145 // Inline pattern fragments into it.
1146 Pattern->InlinePatternFragments();
1148 // Infer as many types as possible. If we cannot infer all of them, we can
1149 // never do anything with this pattern: report it to the user.
1150 if (!Pattern->InferAllTypes())
1151 Pattern->error("Could not infer all types in pattern!");
1153 ListInit *LI = Patterns[i]->getValueAsListInit("ResultInstrs");
1154 if (LI->getSize() == 0) continue; // no pattern.
1156 // Parse the instruction.
1157 TreePattern *Result = new TreePattern(Patterns[i], LI, *this);
1159 // Inline pattern fragments into it.
1160 Result->InlinePatternFragments();
1162 // Infer as many types as possible. If we cannot infer all of them, we can
1163 // never do anything with this pattern: report it to the user.
1164 if (!Result->InferAllTypes())
1165 Result->error("Could not infer all types in pattern result!");
1167 if (Result->getNumTrees() != 1)
1168 Result->error("Cannot handle instructions producing instructions "
1169 "with temporaries yet!");
1172 if (!Pattern->getOnlyTree()->canPatternMatch(Reason, *this))
1173 Pattern->error("Pattern can never match: " + Reason);
1175 PatternsToMatch.push_back(std::make_pair(Pattern->getOnlyTree(),
1176 Result->getOnlyTree()));
1180 /// CombineChildVariants - Given a bunch of permutations of each child of the
1181 /// 'operator' node, put them together in all possible ways.
1182 static void CombineChildVariants(TreePatternNode *Orig,
1183 const std::vector<std::vector<TreePatternNode*> > &ChildVariants,
1184 std::vector<TreePatternNode*> &OutVariants,
1185 DAGISelEmitter &ISE) {
1186 // Make sure that each operand has at least one variant to choose from.
1187 for (unsigned i = 0, e = ChildVariants.size(); i != e; ++i)
1188 if (ChildVariants[i].empty())
1191 // The end result is an all-pairs construction of the resultant pattern.
1192 std::vector<unsigned> Idxs;
1193 Idxs.resize(ChildVariants.size());
1194 bool NotDone = true;
1196 // Create the variant and add it to the output list.
1197 std::vector<TreePatternNode*> NewChildren;
1198 for (unsigned i = 0, e = ChildVariants.size(); i != e; ++i)
1199 NewChildren.push_back(ChildVariants[i][Idxs[i]]);
1200 TreePatternNode *R = new TreePatternNode(Orig->getOperator(), NewChildren);
1202 // Copy over properties.
1203 R->setName(Orig->getName());
1204 R->setPredicateFn(Orig->getPredicateFn());
1205 R->setTransformFn(Orig->getTransformFn());
1206 R->setType(Orig->getExtType());
1208 // If this pattern cannot every match, do not include it as a variant.
1209 std::string ErrString;
1210 if (!R->canPatternMatch(ErrString, ISE)) {
1213 bool AlreadyExists = false;
1215 // Scan to see if this pattern has already been emitted. We can get
1216 // duplication due to things like commuting:
1217 // (and GPRC:$a, GPRC:$b) -> (and GPRC:$b, GPRC:$a)
1218 // which are the same pattern. Ignore the dups.
1219 for (unsigned i = 0, e = OutVariants.size(); i != e; ++i)
1220 if (R->isIsomorphicTo(OutVariants[i])) {
1221 AlreadyExists = true;
1228 OutVariants.push_back(R);
1231 // Increment indices to the next permutation.
1233 // Look for something we can increment without causing a wrap-around.
1234 for (unsigned IdxsIdx = 0; IdxsIdx != Idxs.size(); ++IdxsIdx) {
1235 if (++Idxs[IdxsIdx] < ChildVariants[IdxsIdx].size()) {
1236 NotDone = true; // Found something to increment.
1244 /// CombineChildVariants - A helper function for binary operators.
1246 static void CombineChildVariants(TreePatternNode *Orig,
1247 const std::vector<TreePatternNode*> &LHS,
1248 const std::vector<TreePatternNode*> &RHS,
1249 std::vector<TreePatternNode*> &OutVariants,
1250 DAGISelEmitter &ISE) {
1251 std::vector<std::vector<TreePatternNode*> > ChildVariants;
1252 ChildVariants.push_back(LHS);
1253 ChildVariants.push_back(RHS);
1254 CombineChildVariants(Orig, ChildVariants, OutVariants, ISE);
1258 static void GatherChildrenOfAssociativeOpcode(TreePatternNode *N,
1259 std::vector<TreePatternNode *> &Children) {
1260 assert(N->getNumChildren()==2 &&"Associative but doesn't have 2 children!");
1261 Record *Operator = N->getOperator();
1263 // Only permit raw nodes.
1264 if (!N->getName().empty() || !N->getPredicateFn().empty() ||
1265 N->getTransformFn()) {
1266 Children.push_back(N);
1270 if (N->getChild(0)->isLeaf() || N->getChild(0)->getOperator() != Operator)
1271 Children.push_back(N->getChild(0));
1273 GatherChildrenOfAssociativeOpcode(N->getChild(0), Children);
1275 if (N->getChild(1)->isLeaf() || N->getChild(1)->getOperator() != Operator)
1276 Children.push_back(N->getChild(1));
1278 GatherChildrenOfAssociativeOpcode(N->getChild(1), Children);
1281 /// GenerateVariantsOf - Given a pattern N, generate all permutations we can of
1282 /// the (potentially recursive) pattern by using algebraic laws.
1284 static void GenerateVariantsOf(TreePatternNode *N,
1285 std::vector<TreePatternNode*> &OutVariants,
1286 DAGISelEmitter &ISE) {
1287 // We cannot permute leaves.
1289 OutVariants.push_back(N);
1293 // Look up interesting info about the node.
1294 const SDNodeInfo &NodeInfo = ISE.getSDNodeInfo(N->getOperator());
1296 // If this node is associative, reassociate.
1297 if (NodeInfo.hasProperty(SDNodeInfo::SDNPAssociative)) {
1298 // Reassociate by pulling together all of the linked operators
1299 std::vector<TreePatternNode*> MaximalChildren;
1300 GatherChildrenOfAssociativeOpcode(N, MaximalChildren);
1302 // Only handle child sizes of 3. Otherwise we'll end up trying too many
1304 if (MaximalChildren.size() == 3) {
1305 // Find the variants of all of our maximal children.
1306 std::vector<TreePatternNode*> AVariants, BVariants, CVariants;
1307 GenerateVariantsOf(MaximalChildren[0], AVariants, ISE);
1308 GenerateVariantsOf(MaximalChildren[1], BVariants, ISE);
1309 GenerateVariantsOf(MaximalChildren[2], CVariants, ISE);
1311 // There are only two ways we can permute the tree:
1312 // (A op B) op C and A op (B op C)
1313 // Within these forms, we can also permute A/B/C.
1315 // Generate legal pair permutations of A/B/C.
1316 std::vector<TreePatternNode*> ABVariants;
1317 std::vector<TreePatternNode*> BAVariants;
1318 std::vector<TreePatternNode*> ACVariants;
1319 std::vector<TreePatternNode*> CAVariants;
1320 std::vector<TreePatternNode*> BCVariants;
1321 std::vector<TreePatternNode*> CBVariants;
1322 CombineChildVariants(N, AVariants, BVariants, ABVariants, ISE);
1323 CombineChildVariants(N, BVariants, AVariants, BAVariants, ISE);
1324 CombineChildVariants(N, AVariants, CVariants, ACVariants, ISE);
1325 CombineChildVariants(N, CVariants, AVariants, CAVariants, ISE);
1326 CombineChildVariants(N, BVariants, CVariants, BCVariants, ISE);
1327 CombineChildVariants(N, CVariants, BVariants, CBVariants, ISE);
1329 // Combine those into the result: (x op x) op x
1330 CombineChildVariants(N, ABVariants, CVariants, OutVariants, ISE);
1331 CombineChildVariants(N, BAVariants, CVariants, OutVariants, ISE);
1332 CombineChildVariants(N, ACVariants, BVariants, OutVariants, ISE);
1333 CombineChildVariants(N, CAVariants, BVariants, OutVariants, ISE);
1334 CombineChildVariants(N, BCVariants, AVariants, OutVariants, ISE);
1335 CombineChildVariants(N, CBVariants, AVariants, OutVariants, ISE);
1337 // Combine those into the result: x op (x op x)
1338 CombineChildVariants(N, CVariants, ABVariants, OutVariants, ISE);
1339 CombineChildVariants(N, CVariants, BAVariants, OutVariants, ISE);
1340 CombineChildVariants(N, BVariants, ACVariants, OutVariants, ISE);
1341 CombineChildVariants(N, BVariants, CAVariants, OutVariants, ISE);
1342 CombineChildVariants(N, AVariants, BCVariants, OutVariants, ISE);
1343 CombineChildVariants(N, AVariants, CBVariants, OutVariants, ISE);
1348 // Compute permutations of all children.
1349 std::vector<std::vector<TreePatternNode*> > ChildVariants;
1350 ChildVariants.resize(N->getNumChildren());
1351 for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i)
1352 GenerateVariantsOf(N->getChild(i), ChildVariants[i], ISE);
1354 // Build all permutations based on how the children were formed.
1355 CombineChildVariants(N, ChildVariants, OutVariants, ISE);
1357 // If this node is commutative, consider the commuted order.
1358 if (NodeInfo.hasProperty(SDNodeInfo::SDNPCommutative)) {
1359 assert(N->getNumChildren()==2 &&"Commutative but doesn't have 2 children!");
1360 // Consider the commuted order.
1361 CombineChildVariants(N, ChildVariants[1], ChildVariants[0],
1367 // GenerateVariants - Generate variants. For example, commutative patterns can
1368 // match multiple ways. Add them to PatternsToMatch as well.
1369 void DAGISelEmitter::GenerateVariants() {
1371 DEBUG(std::cerr << "Generating instruction variants.\n");
1373 // Loop over all of the patterns we've collected, checking to see if we can
1374 // generate variants of the instruction, through the exploitation of
1375 // identities. This permits the target to provide agressive matching without
1376 // the .td file having to contain tons of variants of instructions.
1378 // Note that this loop adds new patterns to the PatternsToMatch list, but we
1379 // intentionally do not reconsider these. Any variants of added patterns have
1380 // already been added.
1382 for (unsigned i = 0, e = PatternsToMatch.size(); i != e; ++i) {
1383 std::vector<TreePatternNode*> Variants;
1384 GenerateVariantsOf(PatternsToMatch[i].first, Variants, *this);
1386 assert(!Variants.empty() && "Must create at least original variant!");
1387 Variants.erase(Variants.begin()); // Remove the original pattern.
1389 if (Variants.empty()) // No variants for this pattern.
1392 DEBUG(std::cerr << "FOUND VARIANTS OF: ";
1393 PatternsToMatch[i].first->dump();
1396 for (unsigned v = 0, e = Variants.size(); v != e; ++v) {
1397 TreePatternNode *Variant = Variants[v];
1399 DEBUG(std::cerr << " VAR#" << v << ": ";
1403 // Scan to see if an instruction or explicit pattern already matches this.
1404 bool AlreadyExists = false;
1405 for (unsigned p = 0, e = PatternsToMatch.size(); p != e; ++p) {
1406 // Check to see if this variant already exists.
1407 if (Variant->isIsomorphicTo(PatternsToMatch[p].first)) {
1408 DEBUG(std::cerr << " *** ALREADY EXISTS, ignoring variant.\n");
1409 AlreadyExists = true;
1413 // If we already have it, ignore the variant.
1414 if (AlreadyExists) continue;
1416 // Otherwise, add it to the list of patterns we have.
1417 PatternsToMatch.push_back(std::make_pair(Variant,
1418 PatternsToMatch[i].second));
1421 DEBUG(std::cerr << "\n");
1426 /// getPatternSize - Return the 'size' of this pattern. We want to match large
1427 /// patterns before small ones. This is used to determine the size of a
1429 static unsigned getPatternSize(TreePatternNode *P) {
1430 assert(isExtIntegerVT(P->getExtType()) ||
1431 isExtFloatingPointVT(P->getExtType()) &&
1432 "Not a valid pattern node to size!");
1433 unsigned Size = 1; // The node itself.
1435 // Count children in the count if they are also nodes.
1436 for (unsigned i = 0, e = P->getNumChildren(); i != e; ++i) {
1437 TreePatternNode *Child = P->getChild(i);
1438 if (!Child->isLeaf() && Child->getExtType() != MVT::Other)
1439 Size += getPatternSize(Child);
1445 /// getResultPatternCost - Compute the number of instructions for this pattern.
1446 /// This is a temporary hack. We should really include the instruction
1447 /// latencies in this calculation.
1448 static unsigned getResultPatternCost(TreePatternNode *P) {
1449 if (P->isLeaf()) return 0;
1451 unsigned Cost = P->getOperator()->isSubClassOf("Instruction");
1452 for (unsigned i = 0, e = P->getNumChildren(); i != e; ++i)
1453 Cost += getResultPatternCost(P->getChild(i));
1457 // PatternSortingPredicate - return true if we prefer to match LHS before RHS.
1458 // In particular, we want to match maximal patterns first and lowest cost within
1459 // a particular complexity first.
1460 struct PatternSortingPredicate {
1461 bool operator()(DAGISelEmitter::PatternToMatch *LHS,
1462 DAGISelEmitter::PatternToMatch *RHS) {
1463 unsigned LHSSize = getPatternSize(LHS->first);
1464 unsigned RHSSize = getPatternSize(RHS->first);
1465 if (LHSSize > RHSSize) return true; // LHS -> bigger -> less cost
1466 if (LHSSize < RHSSize) return false;
1468 // If the patterns have equal complexity, compare generated instruction cost
1469 return getResultPatternCost(LHS->second) <getResultPatternCost(RHS->second);
1473 /// EmitMatchForPattern - Emit a matcher for N, going to the label for PatternNo
1474 /// if the match fails. At this point, we already know that the opcode for N
1475 /// matches, and the SDNode for the result has the RootName specified name.
1476 void DAGISelEmitter::EmitMatchForPattern(TreePatternNode *N,
1477 const std::string &RootName,
1478 std::map<std::string,std::string> &VarMap,
1479 unsigned PatternNo, std::ostream &OS) {
1480 assert(!N->isLeaf() && "Cannot match against a leaf!");
1482 // If this node has a name associated with it, capture it in VarMap. If
1483 // we already saw this in the pattern, emit code to verify dagness.
1484 if (!N->getName().empty()) {
1485 std::string &VarMapEntry = VarMap[N->getName()];
1486 if (VarMapEntry.empty()) {
1487 VarMapEntry = RootName;
1489 // If we get here, this is a second reference to a specific name. Since
1490 // we already have checked that the first reference is valid, we don't
1491 // have to recursively match it, just check that it's the same as the
1492 // previously named thing.
1493 OS << " if (" << VarMapEntry << " != " << RootName
1494 << ") goto P" << PatternNo << "Fail;\n";
1499 // Emit code to load the child nodes and match their contents recursively.
1500 for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i) {
1501 OS << " SDOperand " << RootName << i <<" = " << RootName
1502 << ".getOperand(" << i << ");\n";
1503 TreePatternNode *Child = N->getChild(i);
1505 if (!Child->isLeaf()) {
1506 // If it's not a leaf, recursively match.
1507 const SDNodeInfo &CInfo = getSDNodeInfo(Child->getOperator());
1508 OS << " if (" << RootName << i << ".getOpcode() != "
1509 << CInfo.getEnumName() << ") goto P" << PatternNo << "Fail;\n";
1510 EmitMatchForPattern(Child, RootName + utostr(i), VarMap, PatternNo, OS);
1512 // If this child has a name associated with it, capture it in VarMap. If
1513 // we already saw this in the pattern, emit code to verify dagness.
1514 if (!Child->getName().empty()) {
1515 std::string &VarMapEntry = VarMap[Child->getName()];
1516 if (VarMapEntry.empty()) {
1517 VarMapEntry = RootName + utostr(i);
1519 // If we get here, this is a second reference to a specific name. Since
1520 // we already have checked that the first reference is valid, we don't
1521 // have to recursively match it, just check that it's the same as the
1522 // previously named thing.
1523 OS << " if (" << VarMapEntry << " != " << RootName << i
1524 << ") goto P" << PatternNo << "Fail;\n";
1529 // Handle leaves of various types.
1530 Init *LeafVal = Child->getLeafValue();
1531 Record *LeafRec = dynamic_cast<DefInit*>(LeafVal)->getDef();
1532 if (LeafRec->isSubClassOf("RegisterClass")) {
1533 // Handle register references. Nothing to do here.
1534 } else if (LeafRec->isSubClassOf("ValueType")) {
1535 // Make sure this is the specified value type.
1536 OS << " if (cast<VTSDNode>(" << RootName << i << ")->getVT() != "
1537 << "MVT::" << LeafRec->getName() << ") goto P" << PatternNo
1541 assert(0 && "Unknown leaf type!");
1546 // If there is a node predicate for this, emit the call.
1547 if (!N->getPredicateFn().empty())
1548 OS << " if (!" << N->getPredicateFn() << "(" << RootName
1549 << ".Val)) goto P" << PatternNo << "Fail;\n";
1552 /// CodeGenPatternResult - Emit the action for a pattern. Now that it has
1553 /// matched, we actually have to build a DAG!
1554 unsigned DAGISelEmitter::
1555 CodeGenPatternResult(TreePatternNode *N, unsigned &Ctr,
1556 std::map<std::string,std::string> &VariableMap,
1557 std::ostream &OS, bool isRoot) {
1558 // This is something selected from the pattern we matched.
1559 if (!N->getName().empty()) {
1560 assert(!isRoot && "Root of pattern cannot be a leaf!");
1561 std::string &Val = VariableMap[N->getName()];
1562 assert(!Val.empty() &&
1563 "Variable referenced but not defined and not caught earlier!");
1564 if (Val[0] == 'T' && Val[1] == 'm' && Val[2] == 'p') {
1565 // Already selected this operand, just return the tmpval.
1566 return atoi(Val.c_str()+3);
1569 unsigned ResNo = Ctr++;
1570 if (!N->isLeaf() && N->getOperator()->getName() == "imm") {
1571 switch (N->getType()) {
1572 default: assert(0 && "Unknown type for constant node!");
1573 case MVT::i1: OS << " bool Tmp"; break;
1574 case MVT::i8: OS << " unsigned char Tmp"; break;
1575 case MVT::i16: OS << " unsigned short Tmp"; break;
1576 case MVT::i32: OS << " unsigned Tmp"; break;
1577 case MVT::i64: OS << " uint64_t Tmp"; break;
1579 OS << ResNo << "C = cast<ConstantSDNode>(" << Val << ")->getValue();\n";
1580 OS << " SDOperand Tmp" << ResNo << " = CurDAG->getTargetConstant(Tmp"
1581 << ResNo << "C, MVT::" << getEnumName(N->getType()) << ");\n";
1583 OS << " SDOperand Tmp" << ResNo << " = Select(" << Val << ");\n";
1585 // Add Tmp<ResNo> to VariableMap, so that we don't multiply select this
1586 // value if used multiple times by this pattern result.
1587 Val = "Tmp"+utostr(ResNo);
1593 assert(0 && "Unknown leaf type!");
1597 Record *Op = N->getOperator();
1598 if (Op->isSubClassOf("Instruction")) {
1599 // Emit all of the operands.
1600 std::vector<unsigned> Ops;
1601 for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i)
1602 Ops.push_back(CodeGenPatternResult(N->getChild(i), Ctr, VariableMap, OS));
1604 CodeGenInstruction &II = Target.getInstruction(Op->getName());
1605 unsigned ResNo = Ctr++;
1608 OS << " SDOperand Tmp" << ResNo << " = CurDAG->getTargetNode("
1609 << II.Namespace << "::" << II.TheDef->getName() << ", MVT::"
1610 << getEnumName(N->getType());
1611 for (unsigned i = 0, e = Ops.size(); i != e; ++i)
1612 OS << ", Tmp" << Ops[i];
1615 // If this instruction is the root, and if there is only one use of it,
1616 // use SelectNodeTo instead of getTargetNode to avoid an allocation.
1617 OS << " if (N.Val->hasOneUse()) {\n";
1618 OS << " CurDAG->SelectNodeTo(N.Val, "
1619 << II.Namespace << "::" << II.TheDef->getName() << ", MVT::"
1620 << getEnumName(N->getType());
1621 for (unsigned i = 0, e = Ops.size(); i != e; ++i)
1622 OS << ", Tmp" << Ops[i];
1624 OS << " return N;\n";
1625 OS << " } else {\n";
1626 OS << " return CodeGenMap[N] = CurDAG->getTargetNode("
1627 << II.Namespace << "::" << II.TheDef->getName() << ", MVT::"
1628 << getEnumName(N->getType());
1629 for (unsigned i = 0, e = Ops.size(); i != e; ++i)
1630 OS << ", Tmp" << Ops[i];
1635 } else if (Op->isSubClassOf("SDNodeXForm")) {
1636 assert(N->getNumChildren() == 1 && "node xform should have one child!");
1637 unsigned OpVal = CodeGenPatternResult(N->getChild(0), Ctr, VariableMap, OS);
1639 unsigned ResNo = Ctr++;
1640 OS << " SDOperand Tmp" << ResNo << " = Transform_" << Op->getName()
1641 << "(Tmp" << OpVal << ".Val);\n";
1643 OS << " CodeGenMap[N] = Tmp" << ResNo << ";\n";
1644 OS << " return Tmp" << ResNo << ";\n";
1649 assert(0 && "Unknown node in result pattern!");
1654 /// RemoveAllTypes - A quick recursive walk over a pattern which removes all
1655 /// type information from it.
1656 static void RemoveAllTypes(TreePatternNode *N) {
1657 N->setType(MVT::isUnknown);
1659 for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i)
1660 RemoveAllTypes(N->getChild(i));
1663 /// InsertOneTypeCheck - Insert a type-check for an unresolved type in 'Pat' and
1664 /// add it to the tree. 'Pat' and 'Other' are isomorphic trees except that
1665 /// 'Pat' may be missing types. If we find an unresolved type to add a check
1666 /// for, this returns true otherwise false if Pat has all types.
1667 static bool InsertOneTypeCheck(TreePatternNode *Pat, TreePatternNode *Other,
1668 const std::string &Prefix, unsigned PatternNo,
1671 if (!Pat->hasTypeSet()) {
1672 // Move a type over from 'other' to 'pat'.
1673 Pat->setType(Other->getType());
1674 OS << " if (" << Prefix << ".getValueType() != MVT::"
1675 << getName(Pat->getType()) << ") goto P" << PatternNo << "Fail;\n";
1677 } else if (Pat->isLeaf()) {
1681 for (unsigned i = 0, e = Pat->getNumChildren(); i != e; ++i)
1682 if (InsertOneTypeCheck(Pat->getChild(i), Other->getChild(i),
1683 Prefix + utostr(i), PatternNo, OS))
1688 /// EmitCodeForPattern - Given a pattern to match, emit code to the specified
1689 /// stream to match the pattern, and generate the code for the match if it
1691 void DAGISelEmitter::EmitCodeForPattern(PatternToMatch &Pattern,
1693 static unsigned PatternCount = 0;
1694 unsigned PatternNo = PatternCount++;
1695 OS << " { // Pattern #" << PatternNo << ": ";
1696 Pattern.first->print(OS);
1697 OS << "\n // Emits: ";
1698 Pattern.second->print(OS);
1700 OS << " // Pattern complexity = " << getPatternSize(Pattern.first)
1701 << " cost = " << getResultPatternCost(Pattern.second) << "\n";
1703 // Emit the matcher, capturing named arguments in VariableMap.
1704 std::map<std::string,std::string> VariableMap;
1705 EmitMatchForPattern(Pattern.first, "N", VariableMap, PatternNo, OS);
1707 // TP - Get *SOME* tree pattern, we don't care which.
1708 TreePattern &TP = *PatternFragments.begin()->second;
1710 // At this point, we know that we structurally match the pattern, but the
1711 // types of the nodes may not match. Figure out the fewest number of type
1712 // comparisons we need to emit. For example, if there is only one integer
1713 // type supported by a target, there should be no type comparisons at all for
1714 // integer patterns!
1716 // To figure out the fewest number of type checks needed, clone the pattern,
1717 // remove the types, then perform type inference on the pattern as a whole.
1718 // If there are unresolved types, emit an explicit check for those types,
1719 // apply the type to the tree, then rerun type inference. Iterate until all
1720 // types are resolved.
1722 TreePatternNode *Pat = Pattern.first->clone();
1723 RemoveAllTypes(Pat);
1726 // Resolve/propagate as many types as possible.
1728 bool MadeChange = true;
1730 MadeChange = Pat->ApplyTypeConstraints(TP,true/*Ignore reg constraints*/);
1732 assert(0 && "Error: could not find consistent types for something we"
1733 " already decided was ok!");
1737 // Insert a check for an unresolved type and add it to the tree. If we find
1738 // an unresolved type to add a check for, this returns true and we iterate,
1739 // otherwise we are done.
1740 } while (InsertOneTypeCheck(Pat, Pattern.first, "N", PatternNo, OS));
1743 CodeGenPatternResult(Pattern.second, TmpNo,
1744 VariableMap, OS, true /*the root*/);
1747 OS << " }\n P" << PatternNo << "Fail:\n";
1752 /// CompareByRecordName - An ordering predicate that implements less-than by
1753 /// comparing the names records.
1754 struct CompareByRecordName {
1755 bool operator()(const Record *LHS, const Record *RHS) const {
1756 // Sort by name first.
1757 if (LHS->getName() < RHS->getName()) return true;
1758 // If both names are equal, sort by pointer.
1759 return LHS->getName() == RHS->getName() && LHS < RHS;
1764 void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
1765 // Emit boilerplate.
1766 OS << "// The main instruction selector code.\n"
1767 << "SDOperand SelectCode(SDOperand N) {\n"
1768 << " if (N.getOpcode() >= ISD::BUILTIN_OP_END &&\n"
1769 << " N.getOpcode() < PPCISD::FIRST_NUMBER)\n"
1770 << " return N; // Already selected.\n\n"
1771 << " if (!N.Val->hasOneUse()) {\n"
1772 << " std::map<SDOperand, SDOperand>::iterator CGMI = CodeGenMap.find(N);\n"
1773 << " if (CGMI != CodeGenMap.end()) return CGMI->second;\n"
1775 << " switch (N.getOpcode()) {\n"
1776 << " default: break;\n"
1777 << " case ISD::EntryToken: // These leaves remain the same.\n"
1779 << " case ISD::AssertSext:\n"
1780 << " case ISD::AssertZext: {\n"
1781 << " SDOperand Tmp0 = Select(N.getOperand(0));\n"
1782 << " if (!N.Val->hasOneUse()) CodeGenMap[N] = Tmp0;\n"
1783 << " return Tmp0;\n"
1786 // Group the patterns by their top-level opcodes.
1787 std::map<Record*, std::vector<PatternToMatch*>,
1788 CompareByRecordName> PatternsByOpcode;
1789 for (unsigned i = 0, e = PatternsToMatch.size(); i != e; ++i)
1790 PatternsByOpcode[PatternsToMatch[i].first->getOperator()]
1791 .push_back(&PatternsToMatch[i]);
1793 // Loop over all of the case statements.
1794 for (std::map<Record*, std::vector<PatternToMatch*>,
1795 CompareByRecordName>::iterator PBOI = PatternsByOpcode.begin(),
1796 E = PatternsByOpcode.end(); PBOI != E; ++PBOI) {
1797 const SDNodeInfo &OpcodeInfo = getSDNodeInfo(PBOI->first);
1798 std::vector<PatternToMatch*> &Patterns = PBOI->second;
1800 OS << " case " << OpcodeInfo.getEnumName() << ":\n";
1802 // We want to emit all of the matching code now. However, we want to emit
1803 // the matches in order of minimal cost. Sort the patterns so the least
1804 // cost one is at the start.
1805 std::stable_sort(Patterns.begin(), Patterns.end(),
1806 PatternSortingPredicate());
1808 for (unsigned i = 0, e = Patterns.size(); i != e; ++i)
1809 EmitCodeForPattern(*Patterns[i], OS);
1810 OS << " break;\n\n";
1814 OS << " } // end of big switch.\n\n"
1815 << " std::cerr << \"Cannot yet select: \";\n"
1816 << " N.Val->dump();\n"
1817 << " std::cerr << '\\n';\n"
1822 void DAGISelEmitter::run(std::ostream &OS) {
1823 EmitSourceFileHeader("DAG Instruction Selector for the " + Target.getName() +
1826 OS << "// *** NOTE: This file is #included into the middle of the target\n"
1827 << "// *** instruction selector class. These functions are really "
1830 OS << "// Instance var to keep track of multiply used nodes that have \n"
1831 << "// already been selected.\n"
1832 << "std::map<SDOperand, SDOperand> CodeGenMap;\n";
1835 ParseNodeTransforms(OS);
1836 ParsePatternFragments(OS);
1837 ParseInstructions();
1840 // Generate variants. For example, commutative patterns can match
1841 // multiple ways. Add them to PatternsToMatch as well.
1845 DEBUG(std::cerr << "\n\nALL PATTERNS TO MATCH:\n\n";
1846 for (unsigned i = 0, e = PatternsToMatch.size(); i != e; ++i) {
1847 std::cerr << "PATTERN: "; PatternsToMatch[i].first->dump();
1848 std::cerr << "\nRESULT: ";PatternsToMatch[i].second->dump();
1852 // At this point, we have full information about the 'Patterns' we need to
1853 // parse, both implicitly from instructions as well as from explicit pattern
1854 // definitions. Emit the resultant instruction selector.
1855 EmitInstructionSelector(OS);
1857 for (std::map<Record*, TreePattern*>::iterator I = PatternFragments.begin(),
1858 E = PatternFragments.end(); I != E; ++I)
1860 PatternFragments.clear();
1862 Instructions.clear();