1 //===- DAGISelMatcherGen.cpp - Matcher generator --------------------------===//
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 #include "DAGISelMatcher.h"
11 #include "CodeGenDAGPatterns.h"
13 #include "llvm/ADT/SmallVector.h"
14 #include "llvm/ADT/StringMap.h"
19 /// getRegisterValueType - Look up and return the ValueType of the specified
20 /// register. If the register is a member of multiple register classes which
21 /// have different associated types, return MVT::Other.
22 static MVT::SimpleValueType getRegisterValueType(Record *R,
23 const CodeGenTarget &T) {
25 MVT::SimpleValueType VT = MVT::Other;
26 const std::vector<CodeGenRegisterClass> &RCs = T.getRegisterClasses();
27 std::vector<Record*>::const_iterator Element;
29 for (unsigned rc = 0, e = RCs.size(); rc != e; ++rc) {
30 const CodeGenRegisterClass &RC = RCs[rc];
31 if (!std::count(RC.Elements.begin(), RC.Elements.end(), R))
36 VT = RC.getValueTypeNum(0);
40 // In multiple RC's. If the Types of the RC's do not agree, return
41 // MVT::Other. The target is responsible for handling this.
42 if (VT != RC.getValueTypeNum(0))
43 // FIXME2: when does this happen? Abort?
52 const PatternToMatch &Pattern;
53 const CodeGenDAGPatterns &CGP;
55 /// PatWithNoTypes - This is a clone of Pattern.getSrcPattern() that starts
56 /// out with all of the types removed. This allows us to insert type checks
57 /// as we scan the tree.
58 TreePatternNode *PatWithNoTypes;
60 /// VariableMap - A map from variable names ('$dst') to the recorded operand
61 /// number that they were captured as. These are biased by 1 to make
63 StringMap<unsigned> VariableMap;
65 /// NextRecordedOperandNo - As we emit opcodes to record matched values in
66 /// the RecordedNodes array, this keeps track of which slot will be next to
68 unsigned NextRecordedOperandNo;
70 /// MatchedChainNodes - This maintains the position in the recorded nodes
71 /// array of all of the recorded input nodes that have chains.
72 SmallVector<unsigned, 2> MatchedChainNodes;
74 /// MatchedFlagResultNodes - This maintains the position in the recorded
75 /// nodes array of all of the recorded input nodes that have flag results.
76 SmallVector<unsigned, 2> MatchedFlagResultNodes;
78 /// PhysRegInputs - List list has an entry for each explicitly specified
79 /// physreg input to the pattern. The first elt is the Register node, the
80 /// second is the recorded slot number the input pattern match saved it in.
81 SmallVector<std::pair<Record*, unsigned>, 2> PhysRegInputs;
83 /// EmittedMergeInputChains - For nodes that match patterns involving
84 /// chains, is set to true if we emitted the "MergeInputChains" operation.
85 bool EmittedMergeInputChains;
87 /// Matcher - This is the top level of the generated matcher, the result.
90 /// CurPredicate - As we emit matcher nodes, this points to the latest check
91 /// which should have future checks stuck into its Next position.
92 Matcher *CurPredicate;
94 MatcherGen(const PatternToMatch &pattern, const CodeGenDAGPatterns &cgp);
97 delete PatWithNoTypes;
100 void EmitMatcherCode();
101 void EmitResultCode();
103 Matcher *GetMatcher() const { return TheMatcher; }
104 Matcher *GetCurPredicate() const { return CurPredicate; }
106 void AddMatcher(Matcher *NewNode);
107 void InferPossibleTypes();
109 // Matcher Generation.
110 void EmitMatchCode(const TreePatternNode *N, TreePatternNode *NodeNoTypes);
111 void EmitLeafMatchCode(const TreePatternNode *N);
112 void EmitOperatorMatchCode(const TreePatternNode *N,
113 TreePatternNode *NodeNoTypes);
115 // Result Code Generation.
116 unsigned getNamedArgumentSlot(StringRef Name) {
117 unsigned VarMapEntry = VariableMap[Name];
118 assert(VarMapEntry != 0 &&
119 "Variable referenced but not defined and not caught earlier!");
120 return VarMapEntry-1;
123 /// GetInstPatternNode - Get the pattern for an instruction.
124 const TreePatternNode *GetInstPatternNode(const DAGInstruction &Ins,
125 const TreePatternNode *N);
127 void EmitResultOperand(const TreePatternNode *N,
128 SmallVectorImpl<unsigned> &ResultOps);
129 void EmitResultOfNamedOperand(const TreePatternNode *N,
130 SmallVectorImpl<unsigned> &ResultOps);
131 void EmitResultLeafAsOperand(const TreePatternNode *N,
132 SmallVectorImpl<unsigned> &ResultOps);
133 void EmitResultInstructionAsOperand(const TreePatternNode *N,
134 SmallVectorImpl<unsigned> &ResultOps);
135 void EmitResultSDNodeXFormAsOperand(const TreePatternNode *N,
136 SmallVectorImpl<unsigned> &ResultOps);
139 } // end anon namespace.
141 MatcherGen::MatcherGen(const PatternToMatch &pattern,
142 const CodeGenDAGPatterns &cgp)
143 : Pattern(pattern), CGP(cgp), NextRecordedOperandNo(0),
144 EmittedMergeInputChains(false), TheMatcher(0), CurPredicate(0) {
145 // We need to produce the matcher tree for the patterns source pattern. To do
146 // this we need to match the structure as well as the types. To do the type
147 // matching, we want to figure out the fewest number of type checks we need to
148 // emit. For example, if there is only one integer type supported by a
149 // target, there should be no type comparisons at all for integer patterns!
151 // To figure out the fewest number of type checks needed, clone the pattern,
152 // remove the types, then perform type inference on the pattern as a whole.
153 // If there are unresolved types, emit an explicit check for those types,
154 // apply the type to the tree, then rerun type inference. Iterate until all
155 // types are resolved.
157 PatWithNoTypes = Pattern.getSrcPattern()->clone();
158 PatWithNoTypes->RemoveAllTypes();
160 // If there are types that are manifestly known, infer them.
161 InferPossibleTypes();
164 /// InferPossibleTypes - As we emit the pattern, we end up generating type
165 /// checks and applying them to the 'PatWithNoTypes' tree. As we do this, we
166 /// want to propagate implied types as far throughout the tree as possible so
167 /// that we avoid doing redundant type checks. This does the type propagation.
168 void MatcherGen::InferPossibleTypes() {
169 // TP - Get *SOME* tree pattern, we don't care which. It is only used for
170 // diagnostics, which we know are impossible at this point.
171 TreePattern &TP = *CGP.pf_begin()->second;
174 bool MadeChange = true;
176 MadeChange = PatWithNoTypes->ApplyTypeConstraints(TP,
177 true/*Ignore reg constraints*/);
179 errs() << "Type constraint application shouldn't fail!";
185 /// AddMatcher - Add a matcher node to the current graph we're building.
186 void MatcherGen::AddMatcher(Matcher *NewNode) {
187 if (CurPredicate != 0)
188 CurPredicate->setNext(NewNode);
190 TheMatcher = NewNode;
191 CurPredicate = NewNode;
195 //===----------------------------------------------------------------------===//
196 // Pattern Match Generation
197 //===----------------------------------------------------------------------===//
199 /// EmitLeafMatchCode - Generate matching code for leaf nodes.
200 void MatcherGen::EmitLeafMatchCode(const TreePatternNode *N) {
201 assert(N->isLeaf() && "Not a leaf?");
203 // If there are node predicates for this node, generate their checks.
204 for (unsigned i = 0, e = N->getPredicateFns().size(); i != e; ++i)
205 AddMatcher(new CheckPredicateMatcher(N->getPredicateFns()[i]));
207 // Direct match against an integer constant.
208 if (IntInit *II = dynamic_cast<IntInit*>(N->getLeafValue()))
209 return AddMatcher(new CheckIntegerMatcher(II->getValue()));
211 DefInit *DI = dynamic_cast<DefInit*>(N->getLeafValue());
213 errs() << "Unknown leaf kind: " << *DI << "\n";
217 Record *LeafRec = DI->getDef();
218 if (// Handle register references. Nothing to do here, they always match.
219 LeafRec->isSubClassOf("RegisterClass") ||
220 LeafRec->isSubClassOf("PointerLikeRegClass") ||
221 // Place holder for SRCVALUE nodes. Nothing to do here.
222 LeafRec->getName() == "srcvalue")
225 // If we have a physreg reference like (mul gpr:$src, EAX) then we need to
226 // record the register
227 if (LeafRec->isSubClassOf("Register")) {
228 AddMatcher(new RecordMatcher("physreg input "+LeafRec->getName(),
229 NextRecordedOperandNo));
230 PhysRegInputs.push_back(std::make_pair(LeafRec, NextRecordedOperandNo++));
234 if (LeafRec->isSubClassOf("ValueType"))
235 return AddMatcher(new CheckValueTypeMatcher(LeafRec->getName()));
237 if (LeafRec->isSubClassOf("CondCode"))
238 return AddMatcher(new CheckCondCodeMatcher(LeafRec->getName()));
240 if (LeafRec->isSubClassOf("ComplexPattern")) {
241 // We can't model ComplexPattern uses that don't have their name taken yet.
242 // The OPC_CheckComplexPattern operation implicitly records the results.
243 if (N->getName().empty()) {
244 errs() << "We expect complex pattern uses to have names: " << *N << "\n";
248 // Handle complex pattern.
249 const ComplexPattern &CP = CGP.getComplexPattern(LeafRec);
251 // If we're at the root of the pattern, we have to check that the opcode
252 // is a one of the ones requested to be matched.
253 if (N == Pattern.getSrcPattern()) {
254 const std::vector<Record*> &OpNodes = CP.getRootNodes();
255 if (OpNodes.size() == 1) {
256 AddMatcher(new CheckOpcodeMatcher(CGP.getSDNodeInfo(OpNodes[0])));
257 } else if (!OpNodes.empty()) {
258 SmallVector<const SDNodeInfo*, 4> OpNames;
259 for (unsigned i = 0, e = OpNodes.size(); i != e; i++)
260 OpNames.push_back(&CGP.getSDNodeInfo(OpNodes[i]));
261 AddMatcher(new CheckMultiOpcodeMatcher(OpNames.data(), OpNames.size()));
265 // Emit a CheckComplexPat operation, which does the match (aborting if it
266 // fails) and pushes the matched operands onto the recorded nodes list.
267 AddMatcher(new CheckComplexPatMatcher(CP));
269 // Record the right number of operands.
270 NextRecordedOperandNo += CP.getNumOperands();
271 if (CP.hasProperty(SDNPHasChain))
272 ++NextRecordedOperandNo; // Chained node operand.
274 // If the complex pattern has a chain, then we need to keep track of the
275 // fact that we just recorded a chain input. The chain input will be
276 // matched as the last operand of the predicate if it was successful.
277 if (CP.hasProperty(SDNPHasChain)) {
278 // It is the last operand recorded.
279 assert(NextRecordedOperandNo > 1 &&
280 "Should have recorded input/result chains at least!");
281 MatchedChainNodes.push_back(NextRecordedOperandNo-1);
283 // If we need to check chains, do so, see comment for
284 // "NodeHasProperty(SDNPHasChain" below.
285 if (MatchedChainNodes.size() > 1) {
286 // FIXME2: This is broken, we should eliminate this nonsense completely,
287 // but we want to produce the same selections that the old matcher does
289 unsigned PrevOp = MatchedChainNodes[MatchedChainNodes.size()-2];
290 AddMatcher(new CheckChainCompatibleMatcher(PrevOp));
294 // TODO: Complex patterns can't have output flags, if they did, we'd want
299 errs() << "Unknown leaf kind: " << *N << "\n";
303 void MatcherGen::EmitOperatorMatchCode(const TreePatternNode *N,
304 TreePatternNode *NodeNoTypes) {
305 assert(!N->isLeaf() && "Not an operator?");
306 const SDNodeInfo &CInfo = CGP.getSDNodeInfo(N->getOperator());
308 // If this is an 'and R, 1234' where the operation is AND/OR and the RHS is
309 // a constant without a predicate fn that has more that one bit set, handle
310 // this as a special case. This is usually for targets that have special
311 // handling of certain large constants (e.g. alpha with it's 8/16/32-bit
312 // handling stuff). Using these instructions is often far more efficient
313 // than materializing the constant. Unfortunately, both the instcombiner
314 // and the dag combiner can often infer that bits are dead, and thus drop
315 // them from the mask in the dag. For example, it might turn 'AND X, 255'
316 // into 'AND X, 254' if it knows the low bit is set. Emit code that checks
318 if ((N->getOperator()->getName() == "and" ||
319 N->getOperator()->getName() == "or") &&
320 N->getChild(1)->isLeaf() && N->getChild(1)->getPredicateFns().empty() &&
321 N->getPredicateFns().empty()) {
322 if (IntInit *II = dynamic_cast<IntInit*>(N->getChild(1)->getLeafValue())) {
323 if (!isPowerOf2_32(II->getValue())) { // Don't bother with single bits.
324 // If this is at the root of the pattern, we emit a redundant
325 // CheckOpcode so that the following checks get factored properly under
326 // a single opcode check.
327 if (N == Pattern.getSrcPattern())
328 AddMatcher(new CheckOpcodeMatcher(CInfo));
330 // Emit the CheckAndImm/CheckOrImm node.
331 if (N->getOperator()->getName() == "and")
332 AddMatcher(new CheckAndImmMatcher(II->getValue()));
334 AddMatcher(new CheckOrImmMatcher(II->getValue()));
336 // Match the LHS of the AND as appropriate.
337 AddMatcher(new MoveChildMatcher(0));
338 EmitMatchCode(N->getChild(0), NodeNoTypes->getChild(0));
339 AddMatcher(new MoveParentMatcher());
345 // Check that the current opcode lines up.
346 AddMatcher(new CheckOpcodeMatcher(CInfo));
348 // If there are node predicates for this node, generate their checks.
349 for (unsigned i = 0, e = N->getPredicateFns().size(); i != e; ++i)
350 AddMatcher(new CheckPredicateMatcher(N->getPredicateFns()[i]));
353 // If this node has memory references (i.e. is a load or store), tell the
354 // interpreter to capture them in the memref array.
355 if (N->NodeHasProperty(SDNPMemOperand, CGP))
356 AddMatcher(new RecordMemRefMatcher());
358 // If this node has a chain, then the chain is operand #0 is the SDNode, and
359 // the child numbers of the node are all offset by one.
361 if (N->NodeHasProperty(SDNPHasChain, CGP)) {
362 // Record the node and remember it in our chained nodes list.
363 AddMatcher(new RecordMatcher("'" + N->getOperator()->getName() +
365 NextRecordedOperandNo));
366 // Remember all of the input chains our pattern will match.
367 MatchedChainNodes.push_back(NextRecordedOperandNo++);
369 // If this is the second (e.g. indbr(load) or store(add(load))) or third
370 // input chain (e.g. (store (add (load, load))) from msp430) we need to make
371 // sure that folding the chain won't induce cycles in the DAG. This could
372 // happen if there were an intermediate node between the indbr and load, for
374 if (MatchedChainNodes.size() > 1) {
375 // FIXME2: This is broken, we should eliminate this nonsense completely,
376 // but we want to produce the same selections that the old matcher does
378 unsigned PrevOp = MatchedChainNodes[MatchedChainNodes.size()-2];
379 AddMatcher(new CheckChainCompatibleMatcher(PrevOp));
382 // Don't look at the input chain when matching the tree pattern to the
386 // If this node is not the root and the subtree underneath it produces a
387 // chain, then the result of matching the node is also produce a chain.
388 // Beyond that, this means that we're also folding (at least) the root node
389 // into the node that produce the chain (for example, matching
390 // "(add reg, (load ptr))" as a add_with_memory on X86). This is
391 // problematic, if the 'reg' node also uses the load (say, its chain).
396 // | \ DAG's like cheese.
402 // It would be invalid to fold XX and LD. In this case, folding the two
403 // nodes together would induce a cycle in the DAG, making it a 'cyclic DAG'
404 // To prevent this, we emit a dynamic check for legality before allowing
405 // this to be folded.
407 const TreePatternNode *Root = Pattern.getSrcPattern();
408 if (N != Root) { // Not the root of the pattern.
409 // If there is a node between the root and this node, then we definitely
410 // need to emit the check.
411 bool NeedCheck = !Root->hasChild(N);
413 // If it *is* an immediate child of the root, we can still need a check if
414 // the root SDNode has multiple inputs. For us, this means that it is an
415 // intrinsic, has multiple operands, or has other inputs like chain or
418 const SDNodeInfo &PInfo = CGP.getSDNodeInfo(Root->getOperator());
420 Root->getOperator() == CGP.get_intrinsic_void_sdnode() ||
421 Root->getOperator() == CGP.get_intrinsic_w_chain_sdnode() ||
422 Root->getOperator() == CGP.get_intrinsic_wo_chain_sdnode() ||
423 PInfo.getNumOperands() > 1 ||
424 PInfo.hasProperty(SDNPHasChain) ||
425 PInfo.hasProperty(SDNPInFlag) ||
426 PInfo.hasProperty(SDNPOptInFlag);
430 AddMatcher(new CheckFoldableChainNodeMatcher());
434 // If this node has an output flag and isn't the root, remember it.
435 if (N->NodeHasProperty(SDNPOutFlag, CGP) &&
436 N != Pattern.getSrcPattern()) {
437 // TODO: This redundantly records nodes with both flags and chains.
439 // Record the node and remember it in our chained nodes list.
440 AddMatcher(new RecordMatcher("'" + N->getOperator()->getName() +
441 "' flag output node",
442 NextRecordedOperandNo));
443 // Remember all of the nodes with output flags our pattern will match.
444 MatchedFlagResultNodes.push_back(NextRecordedOperandNo++);
447 // If this node is known to have an input flag or if it *might* have an input
448 // flag, capture it as the flag input of the pattern.
449 if (N->NodeHasProperty(SDNPOptInFlag, CGP) ||
450 N->NodeHasProperty(SDNPInFlag, CGP))
451 AddMatcher(new CaptureFlagInputMatcher());
453 for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i, ++OpNo) {
454 // Get the code suitable for matching this child. Move to the child, check
455 // it then move back to the parent.
456 AddMatcher(new MoveChildMatcher(OpNo));
457 EmitMatchCode(N->getChild(i), NodeNoTypes->getChild(i));
458 AddMatcher(new MoveParentMatcher());
463 void MatcherGen::EmitMatchCode(const TreePatternNode *N,
464 TreePatternNode *NodeNoTypes) {
465 // If N and NodeNoTypes don't agree on a type, then this is a case where we
466 // need to do a type check. Emit the check, apply the tyep to NodeNoTypes and
467 // reinfer any correlated types.
468 if (NodeNoTypes->getExtTypes() != N->getExtTypes()) {
469 AddMatcher(new CheckTypeMatcher(N->getTypeNum(0)));
470 NodeNoTypes->setTypes(N->getExtTypes());
471 InferPossibleTypes();
474 // If this node has a name associated with it, capture it in VariableMap. If
475 // we already saw this in the pattern, emit code to verify dagness.
476 if (!N->getName().empty()) {
477 unsigned &VarMapEntry = VariableMap[N->getName()];
478 if (VarMapEntry == 0) {
479 // If it is a named node, we must emit a 'Record' opcode.
480 AddMatcher(new RecordMatcher("$" + N->getName(), NextRecordedOperandNo));
481 VarMapEntry = ++NextRecordedOperandNo;
483 // If we get here, this is a second reference to a specific name. Since
484 // we already have checked that the first reference is valid, we don't
485 // have to recursively match it, just check that it's the same as the
486 // previously named thing.
487 AddMatcher(new CheckSameMatcher(VarMapEntry-1));
493 EmitLeafMatchCode(N);
495 EmitOperatorMatchCode(N, NodeNoTypes);
498 void MatcherGen::EmitMatcherCode() {
499 // If the pattern has a predicate on it (e.g. only enabled when a subtarget
500 // feature is around, do the check).
501 // FIXME: This should get emitted after the match code below to encourage
502 // sharing. This can't happen until we get an X86ISD::AddrMode node made by
503 // dag combine, eliminating the horrible side-effect-full stuff from
504 // X86's MatchAddress.
505 if (!Pattern.getPredicateCheck().empty())
507 CheckPatternPredicateMatcher(Pattern.getPredicateCheck()));
509 // Emit the matcher for the pattern structure and types.
510 EmitMatchCode(Pattern.getSrcPattern(), PatWithNoTypes);
514 //===----------------------------------------------------------------------===//
515 // Node Result Generation
516 //===----------------------------------------------------------------------===//
518 void MatcherGen::EmitResultOfNamedOperand(const TreePatternNode *N,
519 SmallVectorImpl<unsigned> &ResultOps){
520 assert(!N->getName().empty() && "Operand not named!");
522 unsigned SlotNo = getNamedArgumentSlot(N->getName());
524 // A reference to a complex pattern gets all of the results of the complex
526 if (const ComplexPattern *CP = N->getComplexPatternInfo(CGP)) {
527 // The first slot entry is the node itself, the subsequent entries are the
529 for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i)
530 ResultOps.push_back(SlotNo+i+1);
534 // If this is an 'imm' or 'fpimm' node, make sure to convert it to the target
535 // version of the immediate so that it doesn't get selected due to some other
538 StringRef OperatorName = N->getOperator()->getName();
539 if (OperatorName == "imm" || OperatorName == "fpimm") {
540 AddMatcher(new EmitConvertToTargetMatcher(SlotNo));
541 ResultOps.push_back(NextRecordedOperandNo++);
546 ResultOps.push_back(SlotNo);
549 void MatcherGen::EmitResultLeafAsOperand(const TreePatternNode *N,
550 SmallVectorImpl<unsigned> &ResultOps) {
551 assert(N->isLeaf() && "Must be a leaf");
553 if (IntInit *II = dynamic_cast<IntInit*>(N->getLeafValue())) {
554 AddMatcher(new EmitIntegerMatcher(II->getValue(),N->getTypeNum(0)));
555 ResultOps.push_back(NextRecordedOperandNo++);
559 // If this is an explicit register reference, handle it.
560 if (DefInit *DI = dynamic_cast<DefInit*>(N->getLeafValue())) {
561 if (DI->getDef()->isSubClassOf("Register")) {
562 AddMatcher(new EmitRegisterMatcher(DI->getDef(),
564 ResultOps.push_back(NextRecordedOperandNo++);
568 if (DI->getDef()->getName() == "zero_reg") {
569 AddMatcher(new EmitRegisterMatcher(0, N->getTypeNum(0)));
570 ResultOps.push_back(NextRecordedOperandNo++);
574 // Handle a reference to a register class. This is used
575 // in COPY_TO_SUBREG instructions.
576 if (DI->getDef()->isSubClassOf("RegisterClass")) {
577 std::string Value = getQualifiedName(DI->getDef()) + "RegClassID";
578 AddMatcher(new EmitStringIntegerMatcher(Value, MVT::i32));
579 ResultOps.push_back(NextRecordedOperandNo++);
584 errs() << "unhandled leaf node: \n";
588 /// GetInstPatternNode - Get the pattern for an instruction.
590 const TreePatternNode *MatcherGen::
591 GetInstPatternNode(const DAGInstruction &Inst, const TreePatternNode *N) {
592 const TreePattern *InstPat = Inst.getPattern();
594 // FIXME2?: Assume actual pattern comes before "implicit".
595 TreePatternNode *InstPatNode;
597 InstPatNode = InstPat->getTree(0);
598 else if (/*isRoot*/ N == Pattern.getDstPattern())
599 InstPatNode = Pattern.getSrcPattern();
603 if (InstPatNode && !InstPatNode->isLeaf() &&
604 InstPatNode->getOperator()->getName() == "set")
605 InstPatNode = InstPatNode->getChild(InstPatNode->getNumChildren()-1);
611 EmitResultInstructionAsOperand(const TreePatternNode *N,
612 SmallVectorImpl<unsigned> &OutputOps) {
613 Record *Op = N->getOperator();
614 const CodeGenTarget &CGT = CGP.getTargetInfo();
615 CodeGenInstruction &II = CGT.getInstruction(Op->getName());
616 const DAGInstruction &Inst = CGP.getInstruction(Op);
618 // If we can, get the pattern for the instruction we're generating. We derive
619 // a variety of information from this pattern, such as whether it has a chain.
621 // FIXME2: This is extremely dubious for several reasons, not the least of
622 // which it gives special status to instructions with patterns that Pat<>
623 // nodes can't duplicate.
624 const TreePatternNode *InstPatNode = GetInstPatternNode(Inst, N);
626 // NodeHasChain - Whether the instruction node we're creating takes chains.
627 bool NodeHasChain = InstPatNode &&
628 InstPatNode->TreeHasProperty(SDNPHasChain, CGP);
630 bool isRoot = N == Pattern.getDstPattern();
632 // TreeHasOutFlag - True if this tree has a flag.
633 bool TreeHasInFlag = false, TreeHasOutFlag = false;
635 const TreePatternNode *SrcPat = Pattern.getSrcPattern();
636 TreeHasInFlag = SrcPat->TreeHasProperty(SDNPOptInFlag, CGP) ||
637 SrcPat->TreeHasProperty(SDNPInFlag, CGP);
639 // FIXME2: this is checking the entire pattern, not just the node in
640 // question, doing this just for the root seems like a total hack.
641 TreeHasOutFlag = SrcPat->TreeHasProperty(SDNPOutFlag, CGP);
644 // NumResults - This is the number of results produced by the instruction in
646 unsigned NumResults = Inst.getNumResults();
648 // Loop over all of the operands of the instruction pattern, emitting code
649 // to fill them all in. The node 'N' usually has number children equal to
650 // the number of input operands of the instruction. However, in cases
651 // where there are predicate operands for an instruction, we need to fill
652 // in the 'execute always' values. Match up the node operands to the
653 // instruction operands to do this.
654 SmallVector<unsigned, 8> InstOps;
655 for (unsigned ChildNo = 0, InstOpNo = NumResults, e = II.OperandList.size();
656 InstOpNo != e; ++InstOpNo) {
658 // Determine what to emit for this operand.
659 Record *OperandNode = II.OperandList[InstOpNo].Rec;
660 if ((OperandNode->isSubClassOf("PredicateOperand") ||
661 OperandNode->isSubClassOf("OptionalDefOperand")) &&
662 !CGP.getDefaultOperand(OperandNode).DefaultOps.empty()) {
663 // This is a predicate or optional def operand; emit the
664 // 'default ops' operands.
665 const DAGDefaultOperand &DefaultOp =
666 CGP.getDefaultOperand(II.OperandList[InstOpNo].Rec);
667 for (unsigned i = 0, e = DefaultOp.DefaultOps.size(); i != e; ++i)
668 EmitResultOperand(DefaultOp.DefaultOps[i], InstOps);
672 // Otherwise this is a normal operand or a predicate operand without
673 // 'execute always'; emit it.
674 EmitResultOperand(N->getChild(ChildNo), InstOps);
678 // Nodes that match patterns with (potentially multiple) chain inputs have to
679 // merge them together into a token factor.
680 if (NodeHasChain && !EmittedMergeInputChains) {
681 // FIXME2: Move this out of emitresult to a top level place.
682 assert(!MatchedChainNodes.empty() &&
683 "How can this node have chain if no inputs do?");
684 // Otherwise, we have to emit an operation to merge the input chains and
685 // set this as the current input chain.
686 AddMatcher(new EmitMergeInputChainsMatcher
687 (MatchedChainNodes.data(), MatchedChainNodes.size()));
688 EmittedMergeInputChains = true;
691 // If this node has an input flag or explicitly specified input physregs, we
692 // need to add chained and flagged copyfromreg nodes and materialize the flag
694 if (isRoot && !PhysRegInputs.empty()) {
695 // Emit all of the CopyToReg nodes for the input physical registers. These
696 // occur in patterns like (mul:i8 AL:i8, GR8:i8:$src).
697 for (unsigned i = 0, e = PhysRegInputs.size(); i != e; ++i)
698 AddMatcher(new EmitCopyToRegMatcher(PhysRegInputs[i].second,
699 PhysRegInputs[i].first));
700 // Even if the node has no other flag inputs, the resultant node must be
701 // flagged to the CopyFromReg nodes we just generated.
702 TreeHasInFlag = true;
705 // Result order: node results, chain, flags
707 // Determine the result types.
708 SmallVector<MVT::SimpleValueType, 4> ResultVTs;
709 if (NumResults != 0 && N->getTypeNum(0) != MVT::isVoid) {
710 // FIXME2: If the node has multiple results, we should add them. For now,
711 // preserve existing behavior?!
712 ResultVTs.push_back(N->getTypeNum(0));
716 // If this is the root instruction of a pattern that has physical registers in
717 // its result pattern, add output VTs for them. For example, X86 has:
718 // (set AL, (mul ...))
719 // This also handles implicit results like:
721 if (isRoot && Pattern.getDstRegs().size() != 0) {
722 for (unsigned i = 0; i != Pattern.getDstRegs().size(); ++i)
723 if (Pattern.getDstRegs()[i]->isSubClassOf("Register"))
724 ResultVTs.push_back(getRegisterValueType(Pattern.getDstRegs()[i], CGT));
727 // FIXME2: Instead of using the isVariadic flag on the instruction, we should
728 // have an SDNP that indicates variadicism. The TargetInstrInfo isVariadic
729 // property should be inferred from this when an instruction has a pattern.
730 int NumFixedArityOperands = -1;
731 if (isRoot && II.isVariadic)
732 NumFixedArityOperands = Pattern.getSrcPattern()->getNumChildren();
734 // If this is the root node and any of the nodes matched nodes in the input
735 // pattern have MemRefs in them, have the interpreter collect them and plop
736 // them onto this node.
738 // FIXME3: This is actively incorrect for result patterns where the root of
739 // the pattern is not the memory reference and is also incorrect when the
740 // result pattern has multiple memory-referencing instructions. For example,
741 // in the X86 backend, this pattern causes the memrefs to get attached to the
742 // CVTSS2SDrr instead of the MOVSSrm:
744 // def : Pat<(extloadf32 addr:$src),
745 // (CVTSS2SDrr (MOVSSrm addr:$src))>;
747 bool NodeHasMemRefs =
748 isRoot && Pattern.getSrcPattern()->TreeHasProperty(SDNPMemOperand, CGP);
750 AddMatcher(new EmitNodeMatcher(II.Namespace+"::"+II.TheDef->getName(),
751 ResultVTs.data(), ResultVTs.size(),
752 InstOps.data(), InstOps.size(),
753 NodeHasChain, TreeHasInFlag, TreeHasOutFlag,
754 NodeHasMemRefs, NumFixedArityOperands,
755 NextRecordedOperandNo));
757 // The non-chain and non-flag results of the newly emitted node get recorded.
758 for (unsigned i = 0, e = ResultVTs.size(); i != e; ++i) {
759 if (ResultVTs[i] == MVT::Other || ResultVTs[i] == MVT::Flag) break;
760 OutputOps.push_back(NextRecordedOperandNo++);
765 EmitResultSDNodeXFormAsOperand(const TreePatternNode *N,
766 SmallVectorImpl<unsigned> &ResultOps) {
767 assert(N->getOperator()->isSubClassOf("SDNodeXForm") && "Not SDNodeXForm?");
770 SmallVector<unsigned, 8> InputOps;
772 // FIXME2: Could easily generalize this to support multiple inputs and outputs
773 // to the SDNodeXForm. For now we just support one input and one output like
774 // the old instruction selector.
775 assert(N->getNumChildren() == 1);
776 EmitResultOperand(N->getChild(0), InputOps);
778 // The input currently must have produced exactly one result.
779 assert(InputOps.size() == 1 && "Unexpected input to SDNodeXForm");
781 AddMatcher(new EmitNodeXFormMatcher(InputOps[0], N->getOperator()));
782 ResultOps.push_back(NextRecordedOperandNo++);
785 void MatcherGen::EmitResultOperand(const TreePatternNode *N,
786 SmallVectorImpl<unsigned> &ResultOps) {
787 // This is something selected from the pattern we matched.
788 if (!N->getName().empty())
789 return EmitResultOfNamedOperand(N, ResultOps);
792 return EmitResultLeafAsOperand(N, ResultOps);
794 Record *OpRec = N->getOperator();
795 if (OpRec->isSubClassOf("Instruction"))
796 return EmitResultInstructionAsOperand(N, ResultOps);
797 if (OpRec->isSubClassOf("SDNodeXForm"))
798 return EmitResultSDNodeXFormAsOperand(N, ResultOps);
799 errs() << "Unknown result node to emit code for: " << *N << '\n';
800 throw std::string("Unknown node in result pattern!");
803 void MatcherGen::EmitResultCode() {
804 // Codegen the root of the result pattern, capturing the resulting values.
805 SmallVector<unsigned, 8> Ops;
806 EmitResultOperand(Pattern.getDstPattern(), Ops);
808 // At this point, we have however many values the result pattern produces.
809 // However, the input pattern might not need all of these. If there are
810 // excess values at the end (such as condition codes etc) just lop them off.
811 // This doesn't need to worry about flags or chains, just explicit results.
813 // FIXME2: This doesn't work because there is currently no way to get an
814 // accurate count of the # results the source pattern sets. This is because
815 // of the "parallel" construct in X86 land, which looks like this:
817 //def : Pat<(parallel (X86and_flag GR8:$src1, GR8:$src2),
818 // (implicit EFLAGS)),
819 // (AND8rr GR8:$src1, GR8:$src2)>;
821 // This idiom means to match the two-result node X86and_flag (which is
822 // declared as returning a single result, because we can't match multi-result
823 // nodes yet). In this case, we would have to know that the input has two
824 // results. However, mul8r is modelled exactly the same way, but without
825 // implicit defs included. The fix is to support multiple results directly
826 // and eliminate 'parallel'.
828 // FIXME2: When this is fixed, we should revert the terrible hack in the
829 // OPC_EmitNode code in the interpreter.
831 const TreePatternNode *Src = Pattern.getSrcPattern();
832 unsigned NumSrcResults = Src->getTypeNum(0) != MVT::isVoid ? 1 : 0;
833 NumSrcResults += Pattern.getDstRegs().size();
834 assert(Ops.size() >= NumSrcResults && "Didn't provide enough results");
835 Ops.resize(NumSrcResults);
838 // If the matched pattern covers nodes which define a flag result, emit a node
839 // that tells the matcher about them so that it can update their results.
840 if (!MatchedFlagResultNodes.empty())
841 AddMatcher(new MarkFlagResultsMatcher(MatchedFlagResultNodes.data(),
842 MatchedFlagResultNodes.size()));
845 // We know that the resulting pattern has exactly one result/
846 // FIXME2: why? what about something like (set a,b,c, (complexpat))
847 // FIXME2: Implicit results should be pushed here I guess?
848 AddMatcher(new CompleteMatchMatcher(Ops.data(), Ops.size(), Pattern));
852 Matcher *llvm::ConvertPatternToMatcher(const PatternToMatch &Pattern,
853 const CodeGenDAGPatterns &CGP) {
854 MatcherGen Gen(Pattern, CGP);
856 // Generate the code for the matcher.
857 Gen.EmitMatcherCode();
860 // FIXME2: Kill extra MoveParent commands at the end of the matcher sequence.
861 // FIXME2: Split result code out to another table, and make the matcher end
862 // with an "Emit <index>" command. This allows result generation stuff to be
863 // shared and factored?
865 // If the match succeeds, then we generate Pattern.
866 Gen.EmitResultCode();
868 // Unconditional match.
869 return Gen.GetMatcher();