| //===- DAGISelMatcherGen.cpp - Matcher generator --------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "DAGISelMatcher.h" |
| #include "CodeGenDAGPatterns.h" |
| #include "CodeGenRegisters.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/ADT/StringMap.h" |
| #include "llvm/TableGen/Error.h" |
| #include "llvm/TableGen/Record.h" |
| #include <utility> |
| using namespace llvm; |
| |
| |
| /// getRegisterValueType - Look up and return the ValueType of the specified |
| /// register. If the register is a member of multiple register classes which |
| /// have different associated types, return MVT::Other. |
| static MVT::SimpleValueType getRegisterValueType(Record *R, |
| const CodeGenTarget &T) { |
| bool FoundRC = false; |
| MVT::SimpleValueType VT = MVT::Other; |
| const CodeGenRegister *Reg = T.getRegBank().getReg(R); |
| |
| for (const auto &RC : T.getRegBank().getRegClasses()) { |
| if (!RC.contains(Reg)) |
| continue; |
| |
| if (!FoundRC) { |
| FoundRC = true; |
| const ValueTypeByHwMode &VVT = RC.getValueTypeNum(0); |
| if (VVT.isSimple()) |
| VT = VVT.getSimple().SimpleTy; |
| continue; |
| } |
| |
| #ifndef NDEBUG |
| // If this occurs in multiple register classes, they all have to agree. |
| const ValueTypeByHwMode &T = RC.getValueTypeNum(0); |
| assert((!T.isSimple() || T.getSimple().SimpleTy == VT) && |
| "ValueType mismatch between register classes for this register"); |
| #endif |
| } |
| return VT; |
| } |
| |
| |
| namespace { |
| class MatcherGen { |
| const PatternToMatch &Pattern; |
| const CodeGenDAGPatterns &CGP; |
| |
| /// PatWithNoTypes - This is a clone of Pattern.getSrcPattern() that starts |
| /// out with all of the types removed. This allows us to insert type checks |
| /// as we scan the tree. |
| TreePatternNodePtr PatWithNoTypes; |
| |
| /// VariableMap - A map from variable names ('$dst') to the recorded operand |
| /// number that they were captured as. These are biased by 1 to make |
| /// insertion easier. |
| StringMap<unsigned> VariableMap; |
| |
| /// This maintains the recorded operand number that OPC_CheckComplexPattern |
| /// drops each sub-operand into. We don't want to insert these into |
| /// VariableMap because that leads to identity checking if they are |
| /// encountered multiple times. Biased by 1 like VariableMap for |
| /// consistency. |
| StringMap<unsigned> NamedComplexPatternOperands; |
| |
| /// NextRecordedOperandNo - As we emit opcodes to record matched values in |
| /// the RecordedNodes array, this keeps track of which slot will be next to |
| /// record into. |
| unsigned NextRecordedOperandNo; |
| |
| /// MatchedChainNodes - This maintains the position in the recorded nodes |
| /// array of all of the recorded input nodes that have chains. |
| SmallVector<unsigned, 2> MatchedChainNodes; |
| |
| /// MatchedComplexPatterns - This maintains a list of all of the |
| /// ComplexPatterns that we need to check. The second element of each pair |
| /// is the recorded operand number of the input node. |
| SmallVector<std::pair<const TreePatternNode*, |
| unsigned>, 2> MatchedComplexPatterns; |
| |
| /// PhysRegInputs - List list has an entry for each explicitly specified |
| /// physreg input to the pattern. The first elt is the Register node, the |
| /// second is the recorded slot number the input pattern match saved it in. |
| SmallVector<std::pair<Record*, unsigned>, 2> PhysRegInputs; |
| |
| /// Matcher - This is the top level of the generated matcher, the result. |
| Matcher *TheMatcher; |
| |
| /// CurPredicate - As we emit matcher nodes, this points to the latest check |
| /// which should have future checks stuck into its Next position. |
| Matcher *CurPredicate; |
| public: |
| MatcherGen(const PatternToMatch &pattern, const CodeGenDAGPatterns &cgp); |
| |
| bool EmitMatcherCode(unsigned Variant); |
| void EmitResultCode(); |
| |
| Matcher *GetMatcher() const { return TheMatcher; } |
| private: |
| void AddMatcher(Matcher *NewNode); |
| void InferPossibleTypes(unsigned ForceMode); |
| |
| // Matcher Generation. |
| void EmitMatchCode(const TreePatternNode *N, TreePatternNode *NodeNoTypes, |
| unsigned ForceMode); |
| void EmitLeafMatchCode(const TreePatternNode *N); |
| void EmitOperatorMatchCode(const TreePatternNode *N, |
| TreePatternNode *NodeNoTypes, |
| unsigned ForceMode); |
| |
| /// If this is the first time a node with unique identifier Name has been |
| /// seen, record it. Otherwise, emit a check to make sure this is the same |
| /// node. Returns true if this is the first encounter. |
| bool recordUniqueNode(ArrayRef<std::string> Names); |
| |
| // Result Code Generation. |
| unsigned getNamedArgumentSlot(StringRef Name) { |
| unsigned VarMapEntry = VariableMap[Name]; |
| assert(VarMapEntry != 0 && |
| "Variable referenced but not defined and not caught earlier!"); |
| return VarMapEntry-1; |
| } |
| |
| void EmitResultOperand(const TreePatternNode *N, |
| SmallVectorImpl<unsigned> &ResultOps); |
| void EmitResultOfNamedOperand(const TreePatternNode *N, |
| SmallVectorImpl<unsigned> &ResultOps); |
| void EmitResultLeafAsOperand(const TreePatternNode *N, |
| SmallVectorImpl<unsigned> &ResultOps); |
| void EmitResultInstructionAsOperand(const TreePatternNode *N, |
| SmallVectorImpl<unsigned> &ResultOps); |
| void EmitResultSDNodeXFormAsOperand(const TreePatternNode *N, |
| SmallVectorImpl<unsigned> &ResultOps); |
| }; |
| |
| } // end anonymous namespace |
| |
| MatcherGen::MatcherGen(const PatternToMatch &pattern, |
| const CodeGenDAGPatterns &cgp) |
| : Pattern(pattern), CGP(cgp), NextRecordedOperandNo(0), |
| TheMatcher(nullptr), CurPredicate(nullptr) { |
| // We need to produce the matcher tree for the patterns source pattern. To do |
| // this we need to match the structure as well as the types. To do the type |
| // matching, we want to figure out the fewest number of type checks we need to |
| // emit. For example, if there is only one integer type supported by a |
| // target, there should be no type comparisons at all for integer patterns! |
| // |
| // To figure out the fewest number of type checks needed, clone the pattern, |
| // remove the types, then perform type inference on the pattern as a whole. |
| // If there are unresolved types, emit an explicit check for those types, |
| // apply the type to the tree, then rerun type inference. Iterate until all |
| // types are resolved. |
| // |
| PatWithNoTypes = Pattern.getSrcPattern()->clone(); |
| PatWithNoTypes->RemoveAllTypes(); |
| |
| // If there are types that are manifestly known, infer them. |
| InferPossibleTypes(Pattern.getForceMode()); |
| } |
| |
| /// InferPossibleTypes - As we emit the pattern, we end up generating type |
| /// checks and applying them to the 'PatWithNoTypes' tree. As we do this, we |
| /// want to propagate implied types as far throughout the tree as possible so |
| /// that we avoid doing redundant type checks. This does the type propagation. |
| void MatcherGen::InferPossibleTypes(unsigned ForceMode) { |
| // TP - Get *SOME* tree pattern, we don't care which. It is only used for |
| // diagnostics, which we know are impossible at this point. |
| TreePattern &TP = *CGP.pf_begin()->second; |
| TP.getInfer().CodeGen = true; |
| TP.getInfer().ForceMode = ForceMode; |
| |
| bool MadeChange = true; |
| while (MadeChange) |
| MadeChange = PatWithNoTypes->ApplyTypeConstraints(TP, |
| true/*Ignore reg constraints*/); |
| } |
| |
| |
| /// AddMatcher - Add a matcher node to the current graph we're building. |
| void MatcherGen::AddMatcher(Matcher *NewNode) { |
| if (CurPredicate) |
| CurPredicate->setNext(NewNode); |
| else |
| TheMatcher = NewNode; |
| CurPredicate = NewNode; |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Pattern Match Generation |
| //===----------------------------------------------------------------------===// |
| |
| /// EmitLeafMatchCode - Generate matching code for leaf nodes. |
| void MatcherGen::EmitLeafMatchCode(const TreePatternNode *N) { |
| assert(N->isLeaf() && "Not a leaf?"); |
| |
| // Direct match against an integer constant. |
| if (IntInit *II = dyn_cast<IntInit>(N->getLeafValue())) { |
| // If this is the root of the dag we're matching, we emit a redundant opcode |
| // check to ensure that this gets folded into the normal top-level |
| // OpcodeSwitch. |
| if (N == Pattern.getSrcPattern()) { |
| const SDNodeInfo &NI = CGP.getSDNodeInfo(CGP.getSDNodeNamed("imm")); |
| AddMatcher(new CheckOpcodeMatcher(NI)); |
| } |
| |
| return AddMatcher(new CheckIntegerMatcher(II->getValue())); |
| } |
| |
| // An UnsetInit represents a named node without any constraints. |
| if (isa<UnsetInit>(N->getLeafValue())) { |
| assert(N->hasName() && "Unnamed ? leaf"); |
| return; |
| } |
| |
| DefInit *DI = dyn_cast<DefInit>(N->getLeafValue()); |
| if (!DI) { |
| errs() << "Unknown leaf kind: " << *N << "\n"; |
| abort(); |
| } |
| |
| Record *LeafRec = DI->getDef(); |
| |
| // A ValueType leaf node can represent a register when named, or itself when |
| // unnamed. |
| if (LeafRec->isSubClassOf("ValueType")) { |
| // A named ValueType leaf always matches: (add i32:$a, i32:$b). |
| if (N->hasName()) |
| return; |
| // An unnamed ValueType as in (sext_inreg GPR:$foo, i8). |
| return AddMatcher(new CheckValueTypeMatcher(LeafRec->getName())); |
| } |
| |
| if (// Handle register references. Nothing to do here, they always match. |
| LeafRec->isSubClassOf("RegisterClass") || |
| LeafRec->isSubClassOf("RegisterOperand") || |
| LeafRec->isSubClassOf("PointerLikeRegClass") || |
| LeafRec->isSubClassOf("SubRegIndex") || |
| // Place holder for SRCVALUE nodes. Nothing to do here. |
| LeafRec->getName() == "srcvalue") |
| return; |
| |
| // If we have a physreg reference like (mul gpr:$src, EAX) then we need to |
| // record the register |
| if (LeafRec->isSubClassOf("Register")) { |
| AddMatcher(new RecordMatcher("physreg input "+LeafRec->getName().str(), |
| NextRecordedOperandNo)); |
| PhysRegInputs.push_back(std::make_pair(LeafRec, NextRecordedOperandNo++)); |
| return; |
| } |
| |
| if (LeafRec->isSubClassOf("CondCode")) |
| return AddMatcher(new CheckCondCodeMatcher(LeafRec->getName())); |
| |
| if (LeafRec->isSubClassOf("ComplexPattern")) { |
| // We can't model ComplexPattern uses that don't have their name taken yet. |
| // The OPC_CheckComplexPattern operation implicitly records the results. |
| if (N->getName().empty()) { |
| std::string S; |
| raw_string_ostream OS(S); |
| OS << "We expect complex pattern uses to have names: " << *N; |
| PrintFatalError(OS.str()); |
| } |
| |
| // Remember this ComplexPattern so that we can emit it after all the other |
| // structural matches are done. |
| unsigned InputOperand = VariableMap[N->getName()] - 1; |
| MatchedComplexPatterns.push_back(std::make_pair(N, InputOperand)); |
| return; |
| } |
| |
| if (LeafRec->getName() == "immAllOnesV") { |
| // If this is the root of the dag we're matching, we emit a redundant opcode |
| // check to ensure that this gets folded into the normal top-level |
| // OpcodeSwitch. |
| if (N == Pattern.getSrcPattern()) { |
| MVT VT = N->getSimpleType(0); |
| StringRef Name = VT.isScalableVector() ? "splat_vector" : "build_vector"; |
| const SDNodeInfo &NI = CGP.getSDNodeInfo(CGP.getSDNodeNamed(Name)); |
| AddMatcher(new CheckOpcodeMatcher(NI)); |
| } |
| return AddMatcher(new CheckImmAllOnesVMatcher()); |
| } |
| if (LeafRec->getName() == "immAllZerosV") { |
| // If this is the root of the dag we're matching, we emit a redundant opcode |
| // check to ensure that this gets folded into the normal top-level |
| // OpcodeSwitch. |
| if (N == Pattern.getSrcPattern()) { |
| MVT VT = N->getSimpleType(0); |
| StringRef Name = VT.isScalableVector() ? "splat_vector" : "build_vector"; |
| const SDNodeInfo &NI = CGP.getSDNodeInfo(CGP.getSDNodeNamed(Name)); |
| AddMatcher(new CheckOpcodeMatcher(NI)); |
| } |
| return AddMatcher(new CheckImmAllZerosVMatcher()); |
| } |
| |
| errs() << "Unknown leaf kind: " << *N << "\n"; |
| abort(); |
| } |
| |
| void MatcherGen::EmitOperatorMatchCode(const TreePatternNode *N, |
| TreePatternNode *NodeNoTypes, |
| unsigned ForceMode) { |
| assert(!N->isLeaf() && "Not an operator?"); |
| |
| if (N->getOperator()->isSubClassOf("ComplexPattern")) { |
| // The "name" of a non-leaf complex pattern (MY_PAT $op1, $op2) is |
| // "MY_PAT:op1:op2". We should already have validated that the uses are |
| // consistent. |
| std::string PatternName = std::string(N->getOperator()->getName()); |
| for (unsigned i = 0; i < N->getNumChildren(); ++i) { |
| PatternName += ":"; |
| PatternName += N->getChild(i)->getName(); |
| } |
| |
| if (recordUniqueNode(PatternName)) { |
| auto NodeAndOpNum = std::make_pair(N, NextRecordedOperandNo - 1); |
| MatchedComplexPatterns.push_back(NodeAndOpNum); |
| } |
| |
| return; |
| } |
| |
| const SDNodeInfo &CInfo = CGP.getSDNodeInfo(N->getOperator()); |
| |
| // If this is an 'and R, 1234' where the operation is AND/OR and the RHS is |
| // a constant without a predicate fn that has more than one bit set, handle |
| // this as a special case. This is usually for targets that have special |
| // handling of certain large constants (e.g. alpha with it's 8/16/32-bit |
| // handling stuff). Using these instructions is often far more efficient |
| // than materializing the constant. Unfortunately, both the instcombiner |
| // and the dag combiner can often infer that bits are dead, and thus drop |
| // them from the mask in the dag. For example, it might turn 'AND X, 255' |
| // into 'AND X, 254' if it knows the low bit is set. Emit code that checks |
| // to handle this. |
| if ((N->getOperator()->getName() == "and" || |
| N->getOperator()->getName() == "or") && |
| N->getChild(1)->isLeaf() && N->getChild(1)->getPredicateCalls().empty() && |
| N->getPredicateCalls().empty()) { |
| if (IntInit *II = dyn_cast<IntInit>(N->getChild(1)->getLeafValue())) { |
| if (!isPowerOf2_32(II->getValue())) { // Don't bother with single bits. |
| // If this is at the root of the pattern, we emit a redundant |
| // CheckOpcode so that the following checks get factored properly under |
| // a single opcode check. |
| if (N == Pattern.getSrcPattern()) |
| AddMatcher(new CheckOpcodeMatcher(CInfo)); |
| |
| // Emit the CheckAndImm/CheckOrImm node. |
| if (N->getOperator()->getName() == "and") |
| AddMatcher(new CheckAndImmMatcher(II->getValue())); |
| else |
| AddMatcher(new CheckOrImmMatcher(II->getValue())); |
| |
| // Match the LHS of the AND as appropriate. |
| AddMatcher(new MoveChildMatcher(0)); |
| EmitMatchCode(N->getChild(0), NodeNoTypes->getChild(0), ForceMode); |
| AddMatcher(new MoveParentMatcher()); |
| return; |
| } |
| } |
| } |
| |
| // Check that the current opcode lines up. |
| AddMatcher(new CheckOpcodeMatcher(CInfo)); |
| |
| // If this node has memory references (i.e. is a load or store), tell the |
| // interpreter to capture them in the memref array. |
| if (N->NodeHasProperty(SDNPMemOperand, CGP)) |
| AddMatcher(new RecordMemRefMatcher()); |
| |
| // If this node has a chain, then the chain is operand #0 is the SDNode, and |
| // the child numbers of the node are all offset by one. |
| unsigned OpNo = 0; |
| if (N->NodeHasProperty(SDNPHasChain, CGP)) { |
| // Record the node and remember it in our chained nodes list. |
| AddMatcher(new RecordMatcher("'" + N->getOperator()->getName().str() + |
| "' chained node", |
| NextRecordedOperandNo)); |
| // Remember all of the input chains our pattern will match. |
| MatchedChainNodes.push_back(NextRecordedOperandNo++); |
| |
| // Don't look at the input chain when matching the tree pattern to the |
| // SDNode. |
| OpNo = 1; |
| |
| // If this node is not the root and the subtree underneath it produces a |
| // chain, then the result of matching the node is also produce a chain. |
| // Beyond that, this means that we're also folding (at least) the root node |
| // into the node that produce the chain (for example, matching |
| // "(add reg, (load ptr))" as a add_with_memory on X86). This is |
| // problematic, if the 'reg' node also uses the load (say, its chain). |
| // Graphically: |
| // |
| // [LD] |
| // ^ ^ |
| // | \ DAG's like cheese. |
| // / | |
| // / [YY] |
| // | ^ |
| // [XX]--/ |
| // |
| // It would be invalid to fold XX and LD. In this case, folding the two |
| // nodes together would induce a cycle in the DAG, making it a 'cyclic DAG' |
| // To prevent this, we emit a dynamic check for legality before allowing |
| // this to be folded. |
| // |
| const TreePatternNode *Root = Pattern.getSrcPattern(); |
| if (N != Root) { // Not the root of the pattern. |
| // If there is a node between the root and this node, then we definitely |
| // need to emit the check. |
| bool NeedCheck = !Root->hasChild(N); |
| |
| // If it *is* an immediate child of the root, we can still need a check if |
| // the root SDNode has multiple inputs. For us, this means that it is an |
| // intrinsic, has multiple operands, or has other inputs like chain or |
| // glue). |
| if (!NeedCheck) { |
| const SDNodeInfo &PInfo = CGP.getSDNodeInfo(Root->getOperator()); |
| NeedCheck = |
| Root->getOperator() == CGP.get_intrinsic_void_sdnode() || |
| Root->getOperator() == CGP.get_intrinsic_w_chain_sdnode() || |
| Root->getOperator() == CGP.get_intrinsic_wo_chain_sdnode() || |
| PInfo.getNumOperands() > 1 || |
| PInfo.hasProperty(SDNPHasChain) || |
| PInfo.hasProperty(SDNPInGlue) || |
| PInfo.hasProperty(SDNPOptInGlue); |
| } |
| |
| if (NeedCheck) |
| AddMatcher(new CheckFoldableChainNodeMatcher()); |
| } |
| } |
| |
| // If this node has an output glue and isn't the root, remember it. |
| if (N->NodeHasProperty(SDNPOutGlue, CGP) && |
| N != Pattern.getSrcPattern()) { |
| // TODO: This redundantly records nodes with both glues and chains. |
| |
| // Record the node and remember it in our chained nodes list. |
| AddMatcher(new RecordMatcher("'" + N->getOperator()->getName().str() + |
| "' glue output node", |
| NextRecordedOperandNo)); |
| } |
| |
| // If this node is known to have an input glue or if it *might* have an input |
| // glue, capture it as the glue input of the pattern. |
| if (N->NodeHasProperty(SDNPOptInGlue, CGP) || |
| N->NodeHasProperty(SDNPInGlue, CGP)) |
| AddMatcher(new CaptureGlueInputMatcher()); |
| |
| for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i, ++OpNo) { |
| // Get the code suitable for matching this child. Move to the child, check |
| // it then move back to the parent. |
| AddMatcher(new MoveChildMatcher(OpNo)); |
| EmitMatchCode(N->getChild(i), NodeNoTypes->getChild(i), ForceMode); |
| AddMatcher(new MoveParentMatcher()); |
| } |
| } |
| |
| bool MatcherGen::recordUniqueNode(ArrayRef<std::string> Names) { |
| unsigned Entry = 0; |
| for (const std::string &Name : Names) { |
| unsigned &VarMapEntry = VariableMap[Name]; |
| if (!Entry) |
| Entry = VarMapEntry; |
| assert(Entry == VarMapEntry); |
| } |
| |
| bool NewRecord = false; |
| if (Entry == 0) { |
| // If it is a named node, we must emit a 'Record' opcode. |
| std::string WhatFor; |
| for (const std::string &Name : Names) { |
| if (!WhatFor.empty()) |
| WhatFor += ','; |
| WhatFor += "$" + Name; |
| } |
| AddMatcher(new RecordMatcher(WhatFor, NextRecordedOperandNo)); |
| Entry = ++NextRecordedOperandNo; |
| NewRecord = true; |
| } else { |
| // If we get here, this is a second reference to a specific name. Since |
| // we already have checked that the first reference is valid, we don't |
| // have to recursively match it, just check that it's the same as the |
| // previously named thing. |
| AddMatcher(new CheckSameMatcher(Entry-1)); |
| } |
| |
| for (const std::string &Name : Names) |
| VariableMap[Name] = Entry; |
| |
| return NewRecord; |
| } |
| |
| void MatcherGen::EmitMatchCode(const TreePatternNode *N, |
| TreePatternNode *NodeNoTypes, |
| unsigned ForceMode) { |
| // If N and NodeNoTypes don't agree on a type, then this is a case where we |
| // need to do a type check. Emit the check, apply the type to NodeNoTypes and |
| // reinfer any correlated types. |
| SmallVector<unsigned, 2> ResultsToTypeCheck; |
| |
| for (unsigned i = 0, e = NodeNoTypes->getNumTypes(); i != e; ++i) { |
| if (NodeNoTypes->getExtType(i) == N->getExtType(i)) continue; |
| NodeNoTypes->setType(i, N->getExtType(i)); |
| InferPossibleTypes(ForceMode); |
| ResultsToTypeCheck.push_back(i); |
| } |
| |
| // If this node has a name associated with it, capture it in VariableMap. If |
| // we already saw this in the pattern, emit code to verify dagness. |
| SmallVector<std::string, 4> Names; |
| if (!N->getName().empty()) |
| Names.push_back(N->getName()); |
| |
| for (const ScopedName &Name : N->getNamesAsPredicateArg()) { |
| Names.push_back(("pred:" + Twine(Name.getScope()) + ":" + Name.getIdentifier()).str()); |
| } |
| |
| if (!Names.empty()) { |
| if (!recordUniqueNode(Names)) |
| return; |
| } |
| |
| if (N->isLeaf()) |
| EmitLeafMatchCode(N); |
| else |
| EmitOperatorMatchCode(N, NodeNoTypes, ForceMode); |
| |
| // If there are node predicates for this node, generate their checks. |
| for (unsigned i = 0, e = N->getPredicateCalls().size(); i != e; ++i) { |
| const TreePredicateCall &Pred = N->getPredicateCalls()[i]; |
| SmallVector<unsigned, 4> Operands; |
| if (Pred.Fn.usesOperands()) { |
| TreePattern *TP = Pred.Fn.getOrigPatFragRecord(); |
| for (unsigned i = 0; i < TP->getNumArgs(); ++i) { |
| std::string Name = |
| ("pred:" + Twine(Pred.Scope) + ":" + TP->getArgName(i)).str(); |
| Operands.push_back(getNamedArgumentSlot(Name)); |
| } |
| } |
| AddMatcher(new CheckPredicateMatcher(Pred.Fn, Operands)); |
| } |
| |
| for (unsigned i = 0, e = ResultsToTypeCheck.size(); i != e; ++i) |
| AddMatcher(new CheckTypeMatcher(N->getSimpleType(ResultsToTypeCheck[i]), |
| ResultsToTypeCheck[i])); |
| } |
| |
| /// EmitMatcherCode - Generate the code that matches the predicate of this |
| /// pattern for the specified Variant. If the variant is invalid this returns |
| /// true and does not generate code, if it is valid, it returns false. |
| bool MatcherGen::EmitMatcherCode(unsigned Variant) { |
| // If the root of the pattern is a ComplexPattern and if it is specified to |
| // match some number of root opcodes, these are considered to be our variants. |
| // Depending on which variant we're generating code for, emit the root opcode |
| // check. |
| if (const ComplexPattern *CP = |
| Pattern.getSrcPattern()->getComplexPatternInfo(CGP)) { |
| const std::vector<Record*> &OpNodes = CP->getRootNodes(); |
| assert(!OpNodes.empty() &&"Complex Pattern must specify what it can match"); |
| if (Variant >= OpNodes.size()) return true; |
| |
| AddMatcher(new CheckOpcodeMatcher(CGP.getSDNodeInfo(OpNodes[Variant]))); |
| } else { |
| if (Variant != 0) return true; |
| } |
| |
| // Emit the matcher for the pattern structure and types. |
| EmitMatchCode(Pattern.getSrcPattern(), PatWithNoTypes.get(), |
| Pattern.getForceMode()); |
| |
| // If the pattern has a predicate on it (e.g. only enabled when a subtarget |
| // feature is around, do the check). |
| if (!Pattern.getPredicateCheck().empty()) |
| AddMatcher(new CheckPatternPredicateMatcher(Pattern.getPredicateCheck())); |
| |
| // Now that we've completed the structural type match, emit any ComplexPattern |
| // checks (e.g. addrmode matches). We emit this after the structural match |
| // because they are generally more expensive to evaluate and more difficult to |
| // factor. |
| for (unsigned i = 0, e = MatchedComplexPatterns.size(); i != e; ++i) { |
| auto N = MatchedComplexPatterns[i].first; |
| |
| // Remember where the results of this match get stuck. |
| if (N->isLeaf()) { |
| NamedComplexPatternOperands[N->getName()] = NextRecordedOperandNo + 1; |
| } else { |
| unsigned CurOp = NextRecordedOperandNo; |
| for (unsigned i = 0; i < N->getNumChildren(); ++i) { |
| NamedComplexPatternOperands[N->getChild(i)->getName()] = CurOp + 1; |
| CurOp += N->getChild(i)->getNumMIResults(CGP); |
| } |
| } |
| |
| // Get the slot we recorded the value in from the name on the node. |
| unsigned RecNodeEntry = MatchedComplexPatterns[i].second; |
| |
| const ComplexPattern &CP = *N->getComplexPatternInfo(CGP); |
| |
| // Emit a CheckComplexPat operation, which does the match (aborting if it |
| // fails) and pushes the matched operands onto the recorded nodes list. |
| AddMatcher(new CheckComplexPatMatcher(CP, RecNodeEntry, |
| N->getName(), NextRecordedOperandNo)); |
| |
| // Record the right number of operands. |
| NextRecordedOperandNo += CP.getNumOperands(); |
| if (CP.hasProperty(SDNPHasChain)) { |
| // If the complex pattern has a chain, then we need to keep track of the |
| // fact that we just recorded a chain input. The chain input will be |
| // matched as the last operand of the predicate if it was successful. |
| ++NextRecordedOperandNo; // Chained node operand. |
| |
| // It is the last operand recorded. |
| assert(NextRecordedOperandNo > 1 && |
| "Should have recorded input/result chains at least!"); |
| MatchedChainNodes.push_back(NextRecordedOperandNo-1); |
| } |
| |
| // TODO: Complex patterns can't have output glues, if they did, we'd want |
| // to record them. |
| } |
| |
| return false; |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Node Result Generation |
| //===----------------------------------------------------------------------===// |
| |
| void MatcherGen::EmitResultOfNamedOperand(const TreePatternNode *N, |
| SmallVectorImpl<unsigned> &ResultOps){ |
| assert(!N->getName().empty() && "Operand not named!"); |
| |
| if (unsigned SlotNo = NamedComplexPatternOperands[N->getName()]) { |
| // Complex operands have already been completely selected, just find the |
| // right slot ant add the arguments directly. |
| for (unsigned i = 0; i < N->getNumMIResults(CGP); ++i) |
| ResultOps.push_back(SlotNo - 1 + i); |
| |
| return; |
| } |
| |
| unsigned SlotNo = getNamedArgumentSlot(N->getName()); |
| |
| // If this is an 'imm' or 'fpimm' node, make sure to convert it to the target |
| // version of the immediate so that it doesn't get selected due to some other |
| // node use. |
| if (!N->isLeaf()) { |
| StringRef OperatorName = N->getOperator()->getName(); |
| if (OperatorName == "imm" || OperatorName == "fpimm") { |
| AddMatcher(new EmitConvertToTargetMatcher(SlotNo)); |
| ResultOps.push_back(NextRecordedOperandNo++); |
| return; |
| } |
| } |
| |
| for (unsigned i = 0; i < N->getNumMIResults(CGP); ++i) |
| ResultOps.push_back(SlotNo + i); |
| } |
| |
| void MatcherGen::EmitResultLeafAsOperand(const TreePatternNode *N, |
| SmallVectorImpl<unsigned> &ResultOps) { |
| assert(N->isLeaf() && "Must be a leaf"); |
| |
| if (IntInit *II = dyn_cast<IntInit>(N->getLeafValue())) { |
| AddMatcher(new EmitIntegerMatcher(II->getValue(), N->getSimpleType(0))); |
| ResultOps.push_back(NextRecordedOperandNo++); |
| return; |
| } |
| |
| // If this is an explicit register reference, handle it. |
| if (DefInit *DI = dyn_cast<DefInit>(N->getLeafValue())) { |
| Record *Def = DI->getDef(); |
| if (Def->isSubClassOf("Register")) { |
| const CodeGenRegister *Reg = |
| CGP.getTargetInfo().getRegBank().getReg(Def); |
| AddMatcher(new EmitRegisterMatcher(Reg, N->getSimpleType(0))); |
| ResultOps.push_back(NextRecordedOperandNo++); |
| return; |
| } |
| |
| if (Def->getName() == "zero_reg") { |
| AddMatcher(new EmitRegisterMatcher(nullptr, N->getSimpleType(0))); |
| ResultOps.push_back(NextRecordedOperandNo++); |
| return; |
| } |
| |
| if (Def->getName() == "undef_tied_input") { |
| std::array<MVT::SimpleValueType, 1> ResultVTs = {{ N->getSimpleType(0) }}; |
| std::array<unsigned, 0> InstOps; |
| auto IDOperandNo = NextRecordedOperandNo++; |
| AddMatcher(new EmitNodeMatcher("TargetOpcode::IMPLICIT_DEF", |
| ResultVTs, InstOps, false, false, false, |
| false, -1, IDOperandNo)); |
| ResultOps.push_back(IDOperandNo); |
| return; |
| } |
| |
| // Handle a reference to a register class. This is used |
| // in COPY_TO_SUBREG instructions. |
| if (Def->isSubClassOf("RegisterOperand")) |
| Def = Def->getValueAsDef("RegClass"); |
| if (Def->isSubClassOf("RegisterClass")) { |
| // If the register class has an enum integer value greater than 127, the |
| // encoding overflows the limit of 7 bits, which precludes the use of |
| // StringIntegerMatcher. In this case, fallback to using IntegerMatcher. |
| const CodeGenRegisterClass &RC = |
| CGP.getTargetInfo().getRegisterClass(Def); |
| if (RC.EnumValue <= 127) { |
| std::string Value = getQualifiedName(Def) + "RegClassID"; |
| AddMatcher(new EmitStringIntegerMatcher(Value, MVT::i32)); |
| ResultOps.push_back(NextRecordedOperandNo++); |
| } else { |
| AddMatcher(new EmitIntegerMatcher(RC.EnumValue, MVT::i32)); |
| ResultOps.push_back(NextRecordedOperandNo++); |
| } |
| return; |
| } |
| |
| // Handle a subregister index. This is used for INSERT_SUBREG etc. |
| if (Def->isSubClassOf("SubRegIndex")) { |
| const CodeGenRegBank &RB = CGP.getTargetInfo().getRegBank(); |
| // If we have more than 127 subreg indices the encoding can overflow |
| // 7 bit and we cannot use StringInteger. |
| if (RB.getSubRegIndices().size() > 127) { |
| const CodeGenSubRegIndex *I = RB.findSubRegIdx(Def); |
| assert(I && "Cannot find subreg index by name!"); |
| if (I->EnumValue > 127) { |
| AddMatcher(new EmitIntegerMatcher(I->EnumValue, MVT::i32)); |
| ResultOps.push_back(NextRecordedOperandNo++); |
| return; |
| } |
| } |
| std::string Value = getQualifiedName(Def); |
| AddMatcher(new EmitStringIntegerMatcher(Value, MVT::i32)); |
| ResultOps.push_back(NextRecordedOperandNo++); |
| return; |
| } |
| } |
| |
| errs() << "unhandled leaf node:\n"; |
| N->dump(); |
| } |
| |
| static bool |
| mayInstNodeLoadOrStore(const TreePatternNode *N, |
| const CodeGenDAGPatterns &CGP) { |
| Record *Op = N->getOperator(); |
| const CodeGenTarget &CGT = CGP.getTargetInfo(); |
| CodeGenInstruction &II = CGT.getInstruction(Op); |
| return II.mayLoad || II.mayStore; |
| } |
| |
| static unsigned |
| numNodesThatMayLoadOrStore(const TreePatternNode *N, |
| const CodeGenDAGPatterns &CGP) { |
| if (N->isLeaf()) |
| return 0; |
| |
| Record *OpRec = N->getOperator(); |
| if (!OpRec->isSubClassOf("Instruction")) |
| return 0; |
| |
| unsigned Count = 0; |
| if (mayInstNodeLoadOrStore(N, CGP)) |
| ++Count; |
| |
| for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i) |
| Count += numNodesThatMayLoadOrStore(N->getChild(i), CGP); |
| |
| return Count; |
| } |
| |
| void MatcherGen:: |
| EmitResultInstructionAsOperand(const TreePatternNode *N, |
| SmallVectorImpl<unsigned> &OutputOps) { |
| Record *Op = N->getOperator(); |
| const CodeGenTarget &CGT = CGP.getTargetInfo(); |
| CodeGenInstruction &II = CGT.getInstruction(Op); |
| const DAGInstruction &Inst = CGP.getInstruction(Op); |
| |
| bool isRoot = N == Pattern.getDstPattern(); |
| |
| // TreeHasOutGlue - True if this tree has glue. |
| bool TreeHasInGlue = false, TreeHasOutGlue = false; |
| if (isRoot) { |
| const TreePatternNode *SrcPat = Pattern.getSrcPattern(); |
| TreeHasInGlue = SrcPat->TreeHasProperty(SDNPOptInGlue, CGP) || |
| SrcPat->TreeHasProperty(SDNPInGlue, CGP); |
| |
| // FIXME2: this is checking the entire pattern, not just the node in |
| // question, doing this just for the root seems like a total hack. |
| TreeHasOutGlue = SrcPat->TreeHasProperty(SDNPOutGlue, CGP); |
| } |
| |
| // NumResults - This is the number of results produced by the instruction in |
| // the "outs" list. |
| unsigned NumResults = Inst.getNumResults(); |
| |
| // Number of operands we know the output instruction must have. If it is |
| // variadic, we could have more operands. |
| unsigned NumFixedOperands = II.Operands.size(); |
| |
| SmallVector<unsigned, 8> InstOps; |
| |
| // Loop over all of the fixed operands of the instruction pattern, emitting |
| // code to fill them all in. The node 'N' usually has number children equal to |
| // the number of input operands of the instruction. However, in cases where |
| // there are predicate operands for an instruction, we need to fill in the |
| // 'execute always' values. Match up the node operands to the instruction |
| // operands to do this. |
| unsigned ChildNo = 0; |
| |
| // Similarly to the code in TreePatternNode::ApplyTypeConstraints, count the |
| // number of operands at the end of the list which have default values. |
| // Those can come from the pattern if it provides enough arguments, or be |
| // filled in with the default if the pattern hasn't provided them. But any |
| // operand with a default value _before_ the last mandatory one will be |
| // filled in with their defaults unconditionally. |
| unsigned NonOverridableOperands = NumFixedOperands; |
| while (NonOverridableOperands > NumResults && |
| CGP.operandHasDefault(II.Operands[NonOverridableOperands-1].Rec)) |
| --NonOverridableOperands; |
| |
| for (unsigned InstOpNo = NumResults, e = NumFixedOperands; |
| InstOpNo != e; ++InstOpNo) { |
| // Determine what to emit for this operand. |
| Record *OperandNode = II.Operands[InstOpNo].Rec; |
| if (CGP.operandHasDefault(OperandNode) && |
| (InstOpNo < NonOverridableOperands || ChildNo >= N->getNumChildren())) { |
| // This is a predicate or optional def operand which the pattern has not |
| // overridden, or which we aren't letting it override; emit the 'default |
| // ops' operands. |
| const DAGDefaultOperand &DefaultOp |
| = CGP.getDefaultOperand(OperandNode); |
| for (unsigned i = 0, e = DefaultOp.DefaultOps.size(); i != e; ++i) |
| EmitResultOperand(DefaultOp.DefaultOps[i].get(), InstOps); |
| continue; |
| } |
| |
| // Otherwise this is a normal operand or a predicate operand without |
| // 'execute always'; emit it. |
| |
| // For operands with multiple sub-operands we may need to emit |
| // multiple child patterns to cover them all. However, ComplexPattern |
| // children may themselves emit multiple MI operands. |
| unsigned NumSubOps = 1; |
| if (OperandNode->isSubClassOf("Operand")) { |
| DagInit *MIOpInfo = OperandNode->getValueAsDag("MIOperandInfo"); |
| if (unsigned NumArgs = MIOpInfo->getNumArgs()) |
| NumSubOps = NumArgs; |
| } |
| |
| unsigned FinalNumOps = InstOps.size() + NumSubOps; |
| while (InstOps.size() < FinalNumOps) { |
| const TreePatternNode *Child = N->getChild(ChildNo); |
| unsigned BeforeAddingNumOps = InstOps.size(); |
| EmitResultOperand(Child, InstOps); |
| assert(InstOps.size() > BeforeAddingNumOps && "Didn't add any operands"); |
| |
| // If the operand is an instruction and it produced multiple results, just |
| // take the first one. |
| if (!Child->isLeaf() && Child->getOperator()->isSubClassOf("Instruction")) |
| InstOps.resize(BeforeAddingNumOps+1); |
| |
| ++ChildNo; |
| } |
| } |
| |
| // If this is a variadic output instruction (i.e. REG_SEQUENCE), we can't |
| // expand suboperands, use default operands, or other features determined from |
| // the CodeGenInstruction after the fixed operands, which were handled |
| // above. Emit the remaining instructions implicitly added by the use for |
| // variable_ops. |
| if (II.Operands.isVariadic) { |
| for (unsigned I = ChildNo, E = N->getNumChildren(); I < E; ++I) |
| EmitResultOperand(N->getChild(I), InstOps); |
| } |
| |
| // If this node has input glue or explicitly specified input physregs, we |
| // need to add chained and glued copyfromreg nodes and materialize the glue |
| // input. |
| if (isRoot && !PhysRegInputs.empty()) { |
| // Emit all of the CopyToReg nodes for the input physical registers. These |
| // occur in patterns like (mul:i8 AL:i8, GR8:i8:$src). |
| for (unsigned i = 0, e = PhysRegInputs.size(); i != e; ++i) { |
| const CodeGenRegister *Reg = |
| CGP.getTargetInfo().getRegBank().getReg(PhysRegInputs[i].first); |
| AddMatcher(new EmitCopyToRegMatcher(PhysRegInputs[i].second, |
| Reg)); |
| } |
| |
| // Even if the node has no other glue inputs, the resultant node must be |
| // glued to the CopyFromReg nodes we just generated. |
| TreeHasInGlue = true; |
| } |
| |
| // Result order: node results, chain, glue |
| |
| // Determine the result types. |
| SmallVector<MVT::SimpleValueType, 4> ResultVTs; |
| for (unsigned i = 0, e = N->getNumTypes(); i != e; ++i) |
| ResultVTs.push_back(N->getSimpleType(i)); |
| |
| // If this is the root instruction of a pattern that has physical registers in |
| // its result pattern, add output VTs for them. For example, X86 has: |
| // (set AL, (mul ...)) |
| // This also handles implicit results like: |
| // (implicit EFLAGS) |
| if (isRoot && !Pattern.getDstRegs().empty()) { |
| // If the root came from an implicit def in the instruction handling stuff, |
| // don't re-add it. |
| Record *HandledReg = nullptr; |
| if (II.HasOneImplicitDefWithKnownVT(CGT) != MVT::Other) |
| HandledReg = II.ImplicitDefs[0]; |
| |
| for (Record *Reg : Pattern.getDstRegs()) { |
| if (!Reg->isSubClassOf("Register") || Reg == HandledReg) continue; |
| ResultVTs.push_back(getRegisterValueType(Reg, CGT)); |
| } |
| } |
| |
| // If this is the root of the pattern and the pattern we're matching includes |
| // a node that is variadic, mark the generated node as variadic so that it |
| // gets the excess operands from the input DAG. |
| int NumFixedArityOperands = -1; |
| if (isRoot && |
| Pattern.getSrcPattern()->NodeHasProperty(SDNPVariadic, CGP)) |
| NumFixedArityOperands = Pattern.getSrcPattern()->getNumChildren(); |
| |
| // If this is the root node and multiple matched nodes in the input pattern |
| // have MemRefs in them, have the interpreter collect them and plop them onto |
| // this node. If there is just one node with MemRefs, leave them on that node |
| // even if it is not the root. |
| // |
| // FIXME3: This is actively incorrect for result patterns with multiple |
| // memory-referencing instructions. |
| bool PatternHasMemOperands = |
| Pattern.getSrcPattern()->TreeHasProperty(SDNPMemOperand, CGP); |
| |
| bool NodeHasMemRefs = false; |
| if (PatternHasMemOperands) { |
| unsigned NumNodesThatLoadOrStore = |
| numNodesThatMayLoadOrStore(Pattern.getDstPattern(), CGP); |
| bool NodeIsUniqueLoadOrStore = mayInstNodeLoadOrStore(N, CGP) && |
| NumNodesThatLoadOrStore == 1; |
| NodeHasMemRefs = |
| NodeIsUniqueLoadOrStore || (isRoot && (mayInstNodeLoadOrStore(N, CGP) || |
| NumNodesThatLoadOrStore != 1)); |
| } |
| |
| // Determine whether we need to attach a chain to this node. |
| bool NodeHasChain = false; |
| if (Pattern.getSrcPattern()->TreeHasProperty(SDNPHasChain, CGP)) { |
| // For some instructions, we were able to infer from the pattern whether |
| // they should have a chain. Otherwise, attach the chain to the root. |
| // |
| // FIXME2: This is extremely dubious for several reasons, not the least of |
| // which it gives special status to instructions with patterns that Pat<> |
| // nodes can't duplicate. |
| if (II.hasChain_Inferred) |
| NodeHasChain = II.hasChain; |
| else |
| NodeHasChain = isRoot; |
| // Instructions which load and store from memory should have a chain, |
| // regardless of whether they happen to have a pattern saying so. |
| if (II.hasCtrlDep || II.mayLoad || II.mayStore || II.canFoldAsLoad || |
| II.hasSideEffects) |
| NodeHasChain = true; |
| } |
| |
| assert((!ResultVTs.empty() || TreeHasOutGlue || NodeHasChain) && |
| "Node has no result"); |
| |
| AddMatcher(new EmitNodeMatcher(II.Namespace.str()+"::"+II.TheDef->getName().str(), |
| ResultVTs, InstOps, |
| NodeHasChain, TreeHasInGlue, TreeHasOutGlue, |
| NodeHasMemRefs, NumFixedArityOperands, |
| NextRecordedOperandNo)); |
| |
| // The non-chain and non-glue results of the newly emitted node get recorded. |
| for (unsigned i = 0, e = ResultVTs.size(); i != e; ++i) { |
| if (ResultVTs[i] == MVT::Other || ResultVTs[i] == MVT::Glue) break; |
| OutputOps.push_back(NextRecordedOperandNo++); |
| } |
| } |
| |
| void MatcherGen:: |
| EmitResultSDNodeXFormAsOperand(const TreePatternNode *N, |
| SmallVectorImpl<unsigned> &ResultOps) { |
| assert(N->getOperator()->isSubClassOf("SDNodeXForm") && "Not SDNodeXForm?"); |
| |
| // Emit the operand. |
| SmallVector<unsigned, 8> InputOps; |
| |
| // FIXME2: Could easily generalize this to support multiple inputs and outputs |
| // to the SDNodeXForm. For now we just support one input and one output like |
| // the old instruction selector. |
| assert(N->getNumChildren() == 1); |
| EmitResultOperand(N->getChild(0), InputOps); |
| |
| // The input currently must have produced exactly one result. |
| assert(InputOps.size() == 1 && "Unexpected input to SDNodeXForm"); |
| |
| AddMatcher(new EmitNodeXFormMatcher(InputOps[0], N->getOperator())); |
| ResultOps.push_back(NextRecordedOperandNo++); |
| } |
| |
| void MatcherGen::EmitResultOperand(const TreePatternNode *N, |
| SmallVectorImpl<unsigned> &ResultOps) { |
| // This is something selected from the pattern we matched. |
| if (!N->getName().empty()) |
| return EmitResultOfNamedOperand(N, ResultOps); |
| |
| if (N->isLeaf()) |
| return EmitResultLeafAsOperand(N, ResultOps); |
| |
| Record *OpRec = N->getOperator(); |
| if (OpRec->isSubClassOf("Instruction")) |
| return EmitResultInstructionAsOperand(N, ResultOps); |
| if (OpRec->isSubClassOf("SDNodeXForm")) |
| return EmitResultSDNodeXFormAsOperand(N, ResultOps); |
| errs() << "Unknown result node to emit code for: " << *N << '\n'; |
| PrintFatalError("Unknown node in result pattern!"); |
| } |
| |
| void MatcherGen::EmitResultCode() { |
| // Patterns that match nodes with (potentially multiple) chain inputs have to |
| // merge them together into a token factor. This informs the generated code |
| // what all the chained nodes are. |
| if (!MatchedChainNodes.empty()) |
| AddMatcher(new EmitMergeInputChainsMatcher(MatchedChainNodes)); |
| |
| // Codegen the root of the result pattern, capturing the resulting values. |
| SmallVector<unsigned, 8> Ops; |
| EmitResultOperand(Pattern.getDstPattern(), Ops); |
| |
| // At this point, we have however many values the result pattern produces. |
| // However, the input pattern might not need all of these. If there are |
| // excess values at the end (such as implicit defs of condition codes etc) |
| // just lop them off. This doesn't need to worry about glue or chains, just |
| // explicit results. |
| // |
| unsigned NumSrcResults = Pattern.getSrcPattern()->getNumTypes(); |
| |
| // If the pattern also has (implicit) results, count them as well. |
| if (!Pattern.getDstRegs().empty()) { |
| // If the root came from an implicit def in the instruction handling stuff, |
| // don't re-add it. |
| Record *HandledReg = nullptr; |
| const TreePatternNode *DstPat = Pattern.getDstPattern(); |
| if (!DstPat->isLeaf() &&DstPat->getOperator()->isSubClassOf("Instruction")){ |
| const CodeGenTarget &CGT = CGP.getTargetInfo(); |
| CodeGenInstruction &II = CGT.getInstruction(DstPat->getOperator()); |
| |
| if (II.HasOneImplicitDefWithKnownVT(CGT) != MVT::Other) |
| HandledReg = II.ImplicitDefs[0]; |
| } |
| |
| for (Record *Reg : Pattern.getDstRegs()) { |
| if (!Reg->isSubClassOf("Register") || Reg == HandledReg) continue; |
| ++NumSrcResults; |
| } |
| } |
| |
| SmallVector<unsigned, 8> Results(Ops); |
| |
| // Apply result permutation. |
| for (unsigned ResNo = 0; ResNo < Pattern.getDstPattern()->getNumResults(); |
| ++ResNo) { |
| Results[ResNo] = Ops[Pattern.getDstPattern()->getResultIndex(ResNo)]; |
| } |
| |
| Results.resize(NumSrcResults); |
| AddMatcher(new CompleteMatchMatcher(Results, Pattern)); |
| } |
| |
| |
| /// ConvertPatternToMatcher - Create the matcher for the specified pattern with |
| /// the specified variant. If the variant number is invalid, this returns null. |
| Matcher *llvm::ConvertPatternToMatcher(const PatternToMatch &Pattern, |
| unsigned Variant, |
| const CodeGenDAGPatterns &CGP) { |
| MatcherGen Gen(Pattern, CGP); |
| |
| // Generate the code for the matcher. |
| if (Gen.EmitMatcherCode(Variant)) |
| return nullptr; |
| |
| // FIXME2: Kill extra MoveParent commands at the end of the matcher sequence. |
| // FIXME2: Split result code out to another table, and make the matcher end |
| // with an "Emit <index>" command. This allows result generation stuff to be |
| // shared and factored? |
| |
| // If the match succeeds, then we generate Pattern. |
| Gen.EmitResultCode(); |
| |
| // Unconditional match. |
| return Gen.GetMatcher(); |
| } |