//===- 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 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 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 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 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, 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, 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 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 &ResultOps); void EmitResultOfNamedOperand(const TreePatternNode *N, SmallVectorImpl &ResultOps); void EmitResultLeafAsOperand(const TreePatternNode *N, SmallVectorImpl &ResultOps); void EmitResultInstructionAsOperand(const TreePatternNode *N, SmallVectorImpl &ResultOps); void EmitResultSDNodeXFormAsOperand(const TreePatternNode *N, SmallVectorImpl &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.ForceMode); } /// 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(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(N->getLeafValue())) { assert(N->hasName() && "Unnamed ? leaf"); return; } DefInit *DI = dyn_cast(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()) { const SDNodeInfo &NI = CGP.getSDNodeInfo(CGP.getSDNodeNamed("build_vector")); 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()) { const SDNodeInfo &NI = CGP.getSDNodeInfo(CGP.getSDNodeNamed("build_vector")); 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(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 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 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 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 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 &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.ForceMode); // 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 &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 &ResultOps) { assert(N->isLeaf() && "Must be a leaf"); if (IntInit *II = dyn_cast(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(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 ResultVTs = {{ N->getSimpleType(0) }}; std::array 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 &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 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 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 &ResultOps) { assert(N->getOperator()->isSubClassOf("SDNodeXForm") && "Not SDNodeXForm?"); // Emit the operand. SmallVector 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 &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 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 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 " 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(); }