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Diffstat (limited to 'utils/TableGen/DAGISelMatcherGen.cpp')
| -rw-r--r-- | utils/TableGen/DAGISelMatcherGen.cpp | 882 |
1 files changed, 882 insertions, 0 deletions
diff --git a/utils/TableGen/DAGISelMatcherGen.cpp b/utils/TableGen/DAGISelMatcherGen.cpp new file mode 100644 index 0000000..4951a42 --- /dev/null +++ b/utils/TableGen/DAGISelMatcherGen.cpp @@ -0,0 +1,882 @@ +//===- DAGISelMatcherGen.cpp - Matcher generator --------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "DAGISelMatcher.h" +#include "CodeGenDAGPatterns.h" +#include "Record.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringMap.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 std::vector<CodeGenRegisterClass> &RCs = T.getRegisterClasses(); + std::vector<Record*>::const_iterator Element; + + for (unsigned rc = 0, e = RCs.size(); rc != e; ++rc) { + const CodeGenRegisterClass &RC = RCs[rc]; + if (!std::count(RC.Elements.begin(), RC.Elements.end(), R)) + continue; + + if (!FoundRC) { + FoundRC = true; + VT = RC.getValueTypeNum(0); + continue; + } + + // If this occurs in multiple register classes, they all have to agree. + assert(VT == RC.getValueTypeNum(0)); + } + 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. + TreePatternNode *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; + + /// 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; + + /// MatchedFlagResultNodes - This maintains the position in the recorded + /// nodes array of all of the recorded input nodes that have flag results. + SmallVector<unsigned, 2> MatchedFlagResultNodes; + + /// MatchedComplexPatterns - This maintains a list of all of the + /// ComplexPatterns that we need to check. The patterns are known to have + /// names which were recorded. The second element of each pair is the first + /// slot number that the OPC_CheckComplexPat opcode drops the matched + /// results into. + 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); + + ~MatcherGen() { + delete PatWithNoTypes; + } + + bool EmitMatcherCode(unsigned Variant); + void EmitResultCode(); + + Matcher *GetMatcher() const { return TheMatcher; } + Matcher *GetCurPredicate() const { return CurPredicate; } + private: + void AddMatcher(Matcher *NewNode); + void InferPossibleTypes(); + + // Matcher Generation. + void EmitMatchCode(const TreePatternNode *N, TreePatternNode *NodeNoTypes); + void EmitLeafMatchCode(const TreePatternNode *N); + void EmitOperatorMatchCode(const TreePatternNode *N, + TreePatternNode *NodeNoTypes); + + // 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; + } + + /// GetInstPatternNode - Get the pattern for an instruction. + const TreePatternNode *GetInstPatternNode(const DAGInstruction &Ins, + const TreePatternNode *N); + + 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 anon namespace. + +MatcherGen::MatcherGen(const PatternToMatch &pattern, + const CodeGenDAGPatterns &cgp) +: Pattern(pattern), CGP(cgp), NextRecordedOperandNo(0), + TheMatcher(0), CurPredicate(0) { + // 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(); +} + +/// 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() { + // 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; + + try { + bool MadeChange = true; + while (MadeChange) + MadeChange = PatWithNoTypes->ApplyTypeConstraints(TP, + true/*Ignore reg constraints*/); + } catch (...) { + errs() << "Type constraint application shouldn't fail!"; + abort(); + } +} + + +/// AddMatcher - Add a matcher node to the current graph we're building. +void MatcherGen::AddMatcher(Matcher *NewNode) { + if (CurPredicate != 0) + 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 = dynamic_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())); + } + + DefInit *DI = dynamic_cast<DefInit*>(N->getLeafValue()); + if (DI == 0) { + errs() << "Unknown leaf kind: " << *DI << "\n"; + abort(); + } + + Record *LeafRec = DI->getDef(); + if (// Handle register references. Nothing to do here, they always match. + LeafRec->isSubClassOf("RegisterClass") || + LeafRec->isSubClassOf("PointerLikeRegClass") || + // 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(), + NextRecordedOperandNo)); + PhysRegInputs.push_back(std::make_pair(LeafRec, NextRecordedOperandNo++)); + return; + } + + if (LeafRec->isSubClassOf("ValueType")) + return AddMatcher(new CheckValueTypeMatcher(LeafRec->getName())); + + 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()) { + errs() << "We expect complex pattern uses to have names: " << *N << "\n"; + exit(1); + } + + // Remember this ComplexPattern so that we can emit it after all the other + // structural matches are done. + MatchedComplexPatterns.push_back(std::make_pair(N, 0)); + return; + } + + errs() << "Unknown leaf kind: " << *N << "\n"; + abort(); +} + +void MatcherGen::EmitOperatorMatchCode(const TreePatternNode *N, + TreePatternNode *NodeNoTypes) { + assert(!N->isLeaf() && "Not an operator?"); + 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 that 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)->getPredicateFns().empty() && + N->getPredicateFns().empty()) { + if (IntInit *II = dynamic_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)); + 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() + + "' 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 + // flag). + 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(SDNPInFlag) || + PInfo.hasProperty(SDNPOptInFlag); + } + + if (NeedCheck) + AddMatcher(new CheckFoldableChainNodeMatcher()); + } + } + + // If this node has an output flag and isn't the root, remember it. + if (N->NodeHasProperty(SDNPOutFlag, CGP) && + N != Pattern.getSrcPattern()) { + // TODO: This redundantly records nodes with both flags and chains. + + // Record the node and remember it in our chained nodes list. + AddMatcher(new RecordMatcher("'" + N->getOperator()->getName() + + "' flag output node", + NextRecordedOperandNo)); + // Remember all of the nodes with output flags our pattern will match. + MatchedFlagResultNodes.push_back(NextRecordedOperandNo++); + } + + // If this node is known to have an input flag or if it *might* have an input + // flag, capture it as the flag input of the pattern. + if (N->NodeHasProperty(SDNPOptInFlag, CGP) || + N->NodeHasProperty(SDNPInFlag, CGP)) + AddMatcher(new CaptureFlagInputMatcher()); + + 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)); + AddMatcher(new MoveParentMatcher()); + } +} + + +void MatcherGen::EmitMatchCode(const TreePatternNode *N, + TreePatternNode *NodeNoTypes) { + // 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 tyep to NodeNoTypes and + // reinfer any correlated types. + unsigned NodeType = EEVT::isUnknown; + if (NodeNoTypes->getExtTypes() != N->getExtTypes()) { + NodeType = N->getTypeNum(0); + NodeNoTypes->setTypes(N->getExtTypes()); + InferPossibleTypes(); + } + + // 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. + if (!N->getName().empty()) { + unsigned &VarMapEntry = VariableMap[N->getName()]; + if (VarMapEntry == 0) { + // If it is a named node, we must emit a 'Record' opcode. + AddMatcher(new RecordMatcher("$" + N->getName(), NextRecordedOperandNo)); + VarMapEntry = ++NextRecordedOperandNo; + } 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(VarMapEntry-1)); + return; + } + } + + if (N->isLeaf()) + EmitLeafMatchCode(N); + else + EmitOperatorMatchCode(N, NodeNoTypes); + + // If there are node predicates for this node, generate their checks. + for (unsigned i = 0, e = N->getPredicateFns().size(); i != e; ++i) + AddMatcher(new CheckPredicateMatcher(N->getPredicateFns()[i])); + + if (NodeType != EEVT::isUnknown) + AddMatcher(new CheckTypeMatcher((MVT::SimpleValueType)NodeType)); +} + +/// 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); + + // 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) { + const TreePatternNode *N = MatchedComplexPatterns[i].first; + + // Remember where the results of this match get stuck. + MatchedComplexPatterns[i].second = NextRecordedOperandNo; + + // Get the slot we recorded the value in from the name on the node. + unsigned RecNodeEntry = VariableMap[N->getName()]; + assert(!N->getName().empty() && RecNodeEntry && + "Complex pattern should have a name and slot"); + --RecNodeEntry; // Entries in VariableMap are biased. + + const ComplexPattern &CP = + CGP.getComplexPattern(((DefInit*)N->getLeafValue())->getDef()); + + // 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 flags, 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!"); + + // A reference to a complex pattern gets all of the results of the complex + // pattern's match. + if (const ComplexPattern *CP = N->getComplexPatternInfo(CGP)) { + unsigned SlotNo = 0; + for (unsigned i = 0, e = MatchedComplexPatterns.size(); i != e; ++i) + if (MatchedComplexPatterns[i].first->getName() == N->getName()) { + SlotNo = MatchedComplexPatterns[i].second; + break; + } + assert(SlotNo != 0 && "Didn't get a slot number assigned?"); + + // The first slot entry is the node itself, the subsequent entries are the + // matched values. + for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i) + ResultOps.push_back(SlotNo+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; + } + } + + ResultOps.push_back(SlotNo); +} + +void MatcherGen::EmitResultLeafAsOperand(const TreePatternNode *N, + SmallVectorImpl<unsigned> &ResultOps) { + assert(N->isLeaf() && "Must be a leaf"); + + if (IntInit *II = dynamic_cast<IntInit*>(N->getLeafValue())) { + AddMatcher(new EmitIntegerMatcher(II->getValue(),N->getTypeNum(0))); + ResultOps.push_back(NextRecordedOperandNo++); + return; + } + + // If this is an explicit register reference, handle it. + if (DefInit *DI = dynamic_cast<DefInit*>(N->getLeafValue())) { + if (DI->getDef()->isSubClassOf("Register")) { + AddMatcher(new EmitRegisterMatcher(DI->getDef(), + N->getTypeNum(0))); + ResultOps.push_back(NextRecordedOperandNo++); + return; + } + + if (DI->getDef()->getName() == "zero_reg") { + AddMatcher(new EmitRegisterMatcher(0, N->getTypeNum(0))); + ResultOps.push_back(NextRecordedOperandNo++); + return; + } + + // Handle a reference to a register class. This is used + // in COPY_TO_SUBREG instructions. + if (DI->getDef()->isSubClassOf("RegisterClass")) { + std::string Value = getQualifiedName(DI->getDef()) + "RegClassID"; + AddMatcher(new EmitStringIntegerMatcher(Value, MVT::i32)); + ResultOps.push_back(NextRecordedOperandNo++); + return; + } + } + + errs() << "unhandled leaf node: \n"; + N->dump(); +} + +/// GetInstPatternNode - Get the pattern for an instruction. +/// +const TreePatternNode *MatcherGen:: +GetInstPatternNode(const DAGInstruction &Inst, const TreePatternNode *N) { + const TreePattern *InstPat = Inst.getPattern(); + + // FIXME2?: Assume actual pattern comes before "implicit". + TreePatternNode *InstPatNode; + if (InstPat) + InstPatNode = InstPat->getTree(0); + else if (/*isRoot*/ N == Pattern.getDstPattern()) + InstPatNode = Pattern.getSrcPattern(); + else + return 0; + + if (InstPatNode && !InstPatNode->isLeaf() && + InstPatNode->getOperator()->getName() == "set") + InstPatNode = InstPatNode->getChild(InstPatNode->getNumChildren()-1); + + return InstPatNode; +} + +void MatcherGen:: +EmitResultInstructionAsOperand(const TreePatternNode *N, + SmallVectorImpl<unsigned> &OutputOps) { + Record *Op = N->getOperator(); + const CodeGenTarget &CGT = CGP.getTargetInfo(); + CodeGenInstruction &II = CGT.getInstruction(Op->getName()); + const DAGInstruction &Inst = CGP.getInstruction(Op); + + // If we can, get the pattern for the instruction we're generating. We derive + // a variety of information from this pattern, such as whether it has a chain. + // + // 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. + const TreePatternNode *InstPatNode = GetInstPatternNode(Inst, N); + + // NodeHasChain - Whether the instruction node we're creating takes chains. + bool NodeHasChain = InstPatNode && + InstPatNode->TreeHasProperty(SDNPHasChain, CGP); + + bool isRoot = N == Pattern.getDstPattern(); + + // TreeHasOutFlag - True if this tree has a flag. + bool TreeHasInFlag = false, TreeHasOutFlag = false; + if (isRoot) { + const TreePatternNode *SrcPat = Pattern.getSrcPattern(); + TreeHasInFlag = SrcPat->TreeHasProperty(SDNPOptInFlag, CGP) || + SrcPat->TreeHasProperty(SDNPInFlag, 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. + TreeHasOutFlag = SrcPat->TreeHasProperty(SDNPOutFlag, CGP); + } + + // NumResults - This is the number of results produced by the instruction in + // the "outs" list. + unsigned NumResults = Inst.getNumResults(); + + // Loop over all of the 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. + SmallVector<unsigned, 8> InstOps; + for (unsigned ChildNo = 0, InstOpNo = NumResults, e = II.OperandList.size(); + InstOpNo != e; ++InstOpNo) { + + // Determine what to emit for this operand. + Record *OperandNode = II.OperandList[InstOpNo].Rec; + if ((OperandNode->isSubClassOf("PredicateOperand") || + OperandNode->isSubClassOf("OptionalDefOperand")) && + !CGP.getDefaultOperand(OperandNode).DefaultOps.empty()) { + // This is a predicate or optional def operand; emit the + // 'default ops' operands. + const DAGDefaultOperand &DefaultOp = + CGP.getDefaultOperand(II.OperandList[InstOpNo].Rec); + for (unsigned i = 0, e = DefaultOp.DefaultOps.size(); i != e; ++i) + EmitResultOperand(DefaultOp.DefaultOps[i], InstOps); + continue; + } + + // Otherwise this is a normal operand or a predicate operand without + // 'execute always'; emit it. + EmitResultOperand(N->getChild(ChildNo), InstOps); + ++ChildNo; + } + + // If this node has an input flag or explicitly specified input physregs, we + // need to add chained and flagged copyfromreg nodes and materialize the flag + // 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) + AddMatcher(new EmitCopyToRegMatcher(PhysRegInputs[i].second, + PhysRegInputs[i].first)); + // Even if the node has no other flag inputs, the resultant node must be + // flagged to the CopyFromReg nodes we just generated. + TreeHasInFlag = true; + } + + // Result order: node results, chain, flags + + // Determine the result types. + SmallVector<MVT::SimpleValueType, 4> ResultVTs; + if (NumResults != 0 && N->getTypeNum(0) != MVT::isVoid) { + // FIXME2: If the node has multiple results, we should add them. For now, + // preserve existing behavior?! + ResultVTs.push_back(N->getTypeNum(0)); + } + + + // 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().size() != 0) { + for (unsigned i = 0; i != Pattern.getDstRegs().size(); ++i) + if (Pattern.getDstRegs()[i]->isSubClassOf("Register")) + ResultVTs.push_back(getRegisterValueType(Pattern.getDstRegs()[i], CGT)); + } + + // FIXME2: Instead of using the isVariadic flag on the instruction, we should + // have an SDNP that indicates variadicism. The TargetInstrInfo isVariadic + // property should be inferred from this when an instruction has a pattern. + int NumFixedArityOperands = -1; + if (isRoot && II.isVariadic) + NumFixedArityOperands = Pattern.getSrcPattern()->getNumChildren(); + + // If this is the root node and any of the nodes matched nodes in the input + // pattern have MemRefs in them, have the interpreter collect them and plop + // them onto this node. + // + // FIXME3: This is actively incorrect for result patterns where the root of + // the pattern is not the memory reference and is also incorrect when the + // result pattern has multiple memory-referencing instructions. For example, + // in the X86 backend, this pattern causes the memrefs to get attached to the + // CVTSS2SDrr instead of the MOVSSrm: + // + // def : Pat<(extloadf32 addr:$src), + // (CVTSS2SDrr (MOVSSrm addr:$src))>; + // + bool NodeHasMemRefs = + isRoot && Pattern.getSrcPattern()->TreeHasProperty(SDNPMemOperand, CGP); + + AddMatcher(new EmitNodeMatcher(II.Namespace+"::"+II.TheDef->getName(), + ResultVTs.data(), ResultVTs.size(), + InstOps.data(), InstOps.size(), + NodeHasChain, TreeHasInFlag, TreeHasOutFlag, + NodeHasMemRefs, NumFixedArityOperands, + NextRecordedOperandNo)); + + // The non-chain and non-flag 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::Flag) 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'; + throw std::string("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.data(), MatchedChainNodes.size())); + + // 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 condition codes etc) just lop them off. + // This doesn't need to worry about flags or chains, just explicit results. + // + // FIXME2: This doesn't work because there is currently no way to get an + // accurate count of the # results the source pattern sets. This is because + // of the "parallel" construct in X86 land, which looks like this: + // + //def : Pat<(parallel (X86and_flag GR8:$src1, GR8:$src2), + // (implicit EFLAGS)), + // (AND8rr GR8:$src1, GR8:$src2)>; + // + // This idiom means to match the two-result node X86and_flag (which is + // declared as returning a single result, because we can't match multi-result + // nodes yet). In this case, we would have to know that the input has two + // results. However, mul8r is modelled exactly the same way, but without + // implicit defs included. The fix is to support multiple results directly + // and eliminate 'parallel'. + // + // FIXME2: When this is fixed, we should revert the terrible hack in the + // OPC_EmitNode code in the interpreter. +#if 0 + const TreePatternNode *Src = Pattern.getSrcPattern(); + unsigned NumSrcResults = Src->getTypeNum(0) != MVT::isVoid ? 1 : 0; + NumSrcResults += Pattern.getDstRegs().size(); + assert(Ops.size() >= NumSrcResults && "Didn't provide enough results"); + Ops.resize(NumSrcResults); +#endif + + // If the matched pattern covers nodes which define a flag result, emit a node + // that tells the matcher about them so that it can update their results. + if (!MatchedFlagResultNodes.empty()) + AddMatcher(new MarkFlagResultsMatcher(MatchedFlagResultNodes.data(), + MatchedFlagResultNodes.size())); + + AddMatcher(new CompleteMatchMatcher(Ops.data(), Ops.size(), 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 0; + + // 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(); +} + + + |