diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp | 1294 |
1 files changed, 1283 insertions, 11 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp index eead526f099e..2e2020d6183f 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp @@ -723,9 +723,9 @@ void SelectionDAGISel::CodeGenAndEmitDAG() { // code to the MachineBasicBlock. if (TimePassesIsEnabled) { NamedRegionTimer T("Instruction Selection", GroupName); - InstructionSelect(); + DoInstructionSelection(); } else { - InstructionSelect(); + DoInstructionSelection(); } DEBUG(dbgs() << "Selected selection DAG:\n"); @@ -765,6 +765,66 @@ void SelectionDAGISel::CodeGenAndEmitDAG() { DEBUG(BB->dump()); } +void SelectionDAGISel::DoInstructionSelection() { + DEBUG(errs() << "===== Instruction selection begins:\n"); + + PreprocessISelDAG(); + + // Select target instructions for the DAG. + { + // Number all nodes with a topological order and set DAGSize. + DAGSize = CurDAG->AssignTopologicalOrder(); + + // Create a dummy node (which is not added to allnodes), that adds + // a reference to the root node, preventing it from being deleted, + // and tracking any changes of the root. + HandleSDNode Dummy(CurDAG->getRoot()); + ISelPosition = SelectionDAG::allnodes_iterator(CurDAG->getRoot().getNode()); + ++ISelPosition; + + // The AllNodes list is now topological-sorted. Visit the + // nodes by starting at the end of the list (the root of the + // graph) and preceding back toward the beginning (the entry + // node). + while (ISelPosition != CurDAG->allnodes_begin()) { + SDNode *Node = --ISelPosition; + // Skip dead nodes. DAGCombiner is expected to eliminate all dead nodes, + // but there are currently some corner cases that it misses. Also, this + // makes it theoretically possible to disable the DAGCombiner. + if (Node->use_empty()) + continue; + + SDNode *ResNode = Select(Node); + + // FIXME: This is pretty gross. 'Select' should be changed to not return + // anything at all and this code should be nuked with a tactical strike. + + // If node should not be replaced, continue with the next one. + if (ResNode == Node || Node->getOpcode() == ISD::DELETED_NODE) + continue; + // Replace node. + if (ResNode) + ReplaceUses(Node, ResNode); + + // If after the replacement this node is not used any more, + // remove this dead node. + if (Node->use_empty()) { // Don't delete EntryToken, etc. + ISelUpdater ISU(ISelPosition); + CurDAG->RemoveDeadNode(Node, &ISU); + } + } + + CurDAG->setRoot(Dummy.getValue()); + } + DEBUG(errs() << "===== Instruction selection ends:\n"); + + PostprocessISelDAG(); + + // FIXME: This shouldn't be needed, remove it. + CurDAG->RemoveDeadNodes(); +} + + void SelectionDAGISel::SelectAllBasicBlocks(Function &Fn, MachineFunction &MF, MachineModuleInfo *MMI, @@ -1316,13 +1376,29 @@ static SDNode *findFlagUse(SDNode *N) { /// This function recursively traverses up the operand chain, ignoring /// certain nodes. static bool findNonImmUse(SDNode *Use, SDNode* Def, SDNode *ImmedUse, - SDNode *Root, - SmallPtrSet<SDNode*, 16> &Visited) { - if (Use->getNodeId() < Def->getNodeId() || - !Visited.insert(Use)) + SDNode *Root, SmallPtrSet<SDNode*, 16> &Visited, + bool IgnoreChains) { + // The NodeID's are given uniques ID's where a node ID is guaranteed to be + // greater than all of its (recursive) operands. If we scan to a point where + // 'use' is smaller than the node we're scanning for, then we know we will + // never find it. + // + // The Use may be -1 (unassigned) if it is a newly allocated node. This can + // happen because we scan down to newly selected nodes in the case of flag + // uses. + if ((Use->getNodeId() < Def->getNodeId() && Use->getNodeId() != -1)) + return false; + + // Don't revisit nodes if we already scanned it and didn't fail, we know we + // won't fail if we scan it again. + if (!Visited.insert(Use)) return false; for (unsigned i = 0, e = Use->getNumOperands(); i != e; ++i) { + // Ignore chain uses, they are validated by HandleMergeInputChains. + if (Use->getOperand(i).getValueType() == MVT::Other && IgnoreChains) + continue; + SDNode *N = Use->getOperand(i).getNode(); if (N == Def) { if (Use == ImmedUse || Use == Root) @@ -1332,7 +1408,7 @@ static bool findNonImmUse(SDNode *Use, SDNode* Def, SDNode *ImmedUse, } // Traverse up the operand chain. - if (findNonImmUse(N, Def, ImmedUse, Root, Visited)) + if (findNonImmUse(N, Def, ImmedUse, Root, Visited, IgnoreChains)) return true; } return false; @@ -1347,9 +1423,10 @@ static bool findNonImmUse(SDNode *Use, SDNode* Def, SDNode *ImmedUse, /// have one non-chain use, we only need to watch out for load/op/store /// and load/op/cmp case where the root (store / cmp) may reach the load via /// its chain operand. -static inline bool isNonImmUse(SDNode *Root, SDNode *Def, SDNode *ImmedUse) { +static inline bool isNonImmUse(SDNode *Root, SDNode *Def, SDNode *ImmedUse, + bool IgnoreChains) { SmallPtrSet<SDNode*, 16> Visited; - return findNonImmUse(Root, Def, ImmedUse, Root, Visited); + return findNonImmUse(Root, Def, ImmedUse, Root, Visited, IgnoreChains); } /// IsProfitableToFold - Returns true if it's profitable to fold the specific @@ -1362,7 +1439,8 @@ bool SelectionDAGISel::IsProfitableToFold(SDValue N, SDNode *U, /// IsLegalToFold - Returns true if the specific operand node N of /// U can be folded during instruction selection that starts at Root. -bool SelectionDAGISel::IsLegalToFold(SDValue N, SDNode *U, SDNode *Root) const { +bool SelectionDAGISel::IsLegalToFold(SDValue N, SDNode *U, SDNode *Root, + bool IgnoreChains) const { if (OptLevel == CodeGenOpt::None) return false; // If Root use can somehow reach N through a path that that doesn't contain @@ -1416,7 +1494,7 @@ bool SelectionDAGISel::IsLegalToFold(SDValue N, SDNode *U, SDNode *Root) const { VT = Root->getValueType(Root->getNumValues()-1); } - return !isNonImmUse(Root, N.getNode(), U); + return !isNonImmUse(Root, N.getNode(), U, IgnoreChains); } SDNode *SelectionDAGISel::Select_INLINEASM(SDNode *N) { @@ -1428,6 +1506,7 @@ SDNode *SelectionDAGISel::Select_INLINEASM(SDNode *N) { VTs.push_back(MVT::Flag); SDValue New = CurDAG->getNode(ISD::INLINEASM, N->getDebugLoc(), VTs, &Ops[0], Ops.size()); + New->setNodeId(-1); return New.getNode(); } @@ -1443,7 +1522,1200 @@ SDNode *SelectionDAGISel::Select_EH_LABEL(SDNode *N) { MVT::Other, Tmp, Chain); } +/// GetVBR - decode a vbr encoding whose top bit is set. +ALWAYS_INLINE static uint64_t +GetVBR(uint64_t Val, const unsigned char *MatcherTable, unsigned &Idx) { + assert(Val >= 128 && "Not a VBR"); + Val &= 127; // Remove first vbr bit. + + unsigned Shift = 7; + uint64_t NextBits; + do { + NextBits = MatcherTable[Idx++]; + Val |= (NextBits&127) << Shift; + Shift += 7; + } while (NextBits & 128); + + return Val; +} + + +/// UpdateChainsAndFlags - When a match is complete, this method updates uses of +/// interior flag and chain results to use the new flag and chain results. +void SelectionDAGISel:: +UpdateChainsAndFlags(SDNode *NodeToMatch, SDValue InputChain, + const SmallVectorImpl<SDNode*> &ChainNodesMatched, + SDValue InputFlag, + const SmallVectorImpl<SDNode*> &FlagResultNodesMatched, + bool isMorphNodeTo) { + SmallVector<SDNode*, 4> NowDeadNodes; + + ISelUpdater ISU(ISelPosition); + + // Now that all the normal results are replaced, we replace the chain and + // flag results if present. + if (!ChainNodesMatched.empty()) { + assert(InputChain.getNode() != 0 && + "Matched input chains but didn't produce a chain"); + // Loop over all of the nodes we matched that produced a chain result. + // Replace all the chain results with the final chain we ended up with. + for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) { + SDNode *ChainNode = ChainNodesMatched[i]; + + // If this node was already deleted, don't look at it. + if (ChainNode->getOpcode() == ISD::DELETED_NODE) + continue; + + // Don't replace the results of the root node if we're doing a + // MorphNodeTo. + if (ChainNode == NodeToMatch && isMorphNodeTo) + continue; + + SDValue ChainVal = SDValue(ChainNode, ChainNode->getNumValues()-1); + if (ChainVal.getValueType() == MVT::Flag) + ChainVal = ChainVal.getValue(ChainVal->getNumValues()-2); + assert(ChainVal.getValueType() == MVT::Other && "Not a chain?"); + CurDAG->ReplaceAllUsesOfValueWith(ChainVal, InputChain, &ISU); + + // If the node became dead, delete it. + if (ChainNode->use_empty()) + NowDeadNodes.push_back(ChainNode); + } + } + + // If the result produces a flag, update any flag results in the matched + // pattern with the flag result. + if (InputFlag.getNode() != 0) { + // Handle any interior nodes explicitly marked. + for (unsigned i = 0, e = FlagResultNodesMatched.size(); i != e; ++i) { + SDNode *FRN = FlagResultNodesMatched[i]; + + // If this node was already deleted, don't look at it. + if (FRN->getOpcode() == ISD::DELETED_NODE) + continue; + + assert(FRN->getValueType(FRN->getNumValues()-1) == MVT::Flag && + "Doesn't have a flag result"); + CurDAG->ReplaceAllUsesOfValueWith(SDValue(FRN, FRN->getNumValues()-1), + InputFlag, &ISU); + + // If the node became dead, delete it. + if (FRN->use_empty()) + NowDeadNodes.push_back(FRN); + } + } + + if (!NowDeadNodes.empty()) + CurDAG->RemoveDeadNodes(NowDeadNodes, &ISU); + + DEBUG(errs() << "ISEL: Match complete!\n"); +} + +enum ChainResult { + CR_Simple, + CR_InducesCycle, + CR_LeadsToInteriorNode +}; + +/// WalkChainUsers - Walk down the users of the specified chained node that is +/// part of the pattern we're matching, looking at all of the users we find. +/// This determines whether something is an interior node, whether we have a +/// non-pattern node in between two pattern nodes (which prevent folding because +/// it would induce a cycle) and whether we have a TokenFactor node sandwiched +/// between pattern nodes (in which case the TF becomes part of the pattern). +/// +/// The walk we do here is guaranteed to be small because we quickly get down to +/// already selected nodes "below" us. +static ChainResult +WalkChainUsers(SDNode *ChainedNode, + SmallVectorImpl<SDNode*> &ChainedNodesInPattern, + SmallVectorImpl<SDNode*> &InteriorChainedNodes) { + ChainResult Result = CR_Simple; + + for (SDNode::use_iterator UI = ChainedNode->use_begin(), + E = ChainedNode->use_end(); UI != E; ++UI) { + // Make sure the use is of the chain, not some other value we produce. + if (UI.getUse().getValueType() != MVT::Other) continue; + + SDNode *User = *UI; + + // If we see an already-selected machine node, then we've gone beyond the + // pattern that we're selecting down into the already selected chunk of the + // DAG. + if (User->isMachineOpcode() || + User->getOpcode() == ISD::HANDLENODE) // Root of the graph. + continue; + + if (User->getOpcode() == ISD::CopyToReg || + User->getOpcode() == ISD::CopyFromReg || + User->getOpcode() == ISD::INLINEASM) { + // If their node ID got reset to -1 then they've already been selected. + // Treat them like a MachineOpcode. + if (User->getNodeId() == -1) + continue; + } + + // If we have a TokenFactor, we handle it specially. + if (User->getOpcode() != ISD::TokenFactor) { + // If the node isn't a token factor and isn't part of our pattern, then it + // must be a random chained node in between two nodes we're selecting. + // This happens when we have something like: + // x = load ptr + // call + // y = x+4 + // store y -> ptr + // Because we structurally match the load/store as a read/modify/write, + // but the call is chained between them. We cannot fold in this case + // because it would induce a cycle in the graph. + if (!std::count(ChainedNodesInPattern.begin(), + ChainedNodesInPattern.end(), User)) + return CR_InducesCycle; + + // Otherwise we found a node that is part of our pattern. For example in: + // x = load ptr + // y = x+4 + // store y -> ptr + // This would happen when we're scanning down from the load and see the + // store as a user. Record that there is a use of ChainedNode that is + // part of the pattern and keep scanning uses. + Result = CR_LeadsToInteriorNode; + InteriorChainedNodes.push_back(User); + continue; + } + + // If we found a TokenFactor, there are two cases to consider: first if the + // TokenFactor is just hanging "below" the pattern we're matching (i.e. no + // uses of the TF are in our pattern) we just want to ignore it. Second, + // the TokenFactor can be sandwiched in between two chained nodes, like so: + // [Load chain] + // ^ + // | + // [Load] + // ^ ^ + // | \ DAG's like cheese + // / \ do you? + // / | + // [TokenFactor] [Op] + // ^ ^ + // | | + // \ / + // \ / + // [Store] + // + // In this case, the TokenFactor becomes part of our match and we rewrite it + // as a new TokenFactor. + // + // To distinguish these two cases, do a recursive walk down the uses. + switch (WalkChainUsers(User, ChainedNodesInPattern, InteriorChainedNodes)) { + case CR_Simple: + // If the uses of the TokenFactor are just already-selected nodes, ignore + // it, it is "below" our pattern. + continue; + case CR_InducesCycle: + // If the uses of the TokenFactor lead to nodes that are not part of our + // pattern that are not selected, folding would turn this into a cycle, + // bail out now. + return CR_InducesCycle; + case CR_LeadsToInteriorNode: + break; // Otherwise, keep processing. + } + + // Okay, we know we're in the interesting interior case. The TokenFactor + // is now going to be considered part of the pattern so that we rewrite its + // uses (it may have uses that are not part of the pattern) with the + // ultimate chain result of the generated code. We will also add its chain + // inputs as inputs to the ultimate TokenFactor we create. + Result = CR_LeadsToInteriorNode; + ChainedNodesInPattern.push_back(User); + InteriorChainedNodes.push_back(User); + continue; + } + + return Result; +} + +/// HandleMergeInputChains - This implements the OPC_EmitMergeInputChains +/// operation for when the pattern matched at least one node with a chains. The +/// input vector contains a list of all of the chained nodes that we match. We +/// must determine if this is a valid thing to cover (i.e. matching it won't +/// induce cycles in the DAG) and if so, creating a TokenFactor node. that will +/// be used as the input node chain for the generated nodes. +static SDValue +HandleMergeInputChains(SmallVectorImpl<SDNode*> &ChainNodesMatched, + SelectionDAG *CurDAG) { + // Walk all of the chained nodes we've matched, recursively scanning down the + // users of the chain result. This adds any TokenFactor nodes that are caught + // in between chained nodes to the chained and interior nodes list. + SmallVector<SDNode*, 3> InteriorChainedNodes; + for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) { + if (WalkChainUsers(ChainNodesMatched[i], ChainNodesMatched, + InteriorChainedNodes) == CR_InducesCycle) + return SDValue(); // Would induce a cycle. + } + + // Okay, we have walked all the matched nodes and collected TokenFactor nodes + // that we are interested in. Form our input TokenFactor node. + SmallVector<SDValue, 3> InputChains; + for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) { + // Add the input chain of this node to the InputChains list (which will be + // the operands of the generated TokenFactor) if it's not an interior node. + SDNode *N = ChainNodesMatched[i]; + if (N->getOpcode() != ISD::TokenFactor) { + if (std::count(InteriorChainedNodes.begin(),InteriorChainedNodes.end(),N)) + continue; + + // Otherwise, add the input chain. + SDValue InChain = ChainNodesMatched[i]->getOperand(0); + assert(InChain.getValueType() == MVT::Other && "Not a chain"); + InputChains.push_back(InChain); + continue; + } + + // If we have a token factor, we want to add all inputs of the token factor + // that are not part of the pattern we're matching. + for (unsigned op = 0, e = N->getNumOperands(); op != e; ++op) { + if (!std::count(ChainNodesMatched.begin(), ChainNodesMatched.end(), + N->getOperand(op).getNode())) + InputChains.push_back(N->getOperand(op)); + } + } + + SDValue Res; + if (InputChains.size() == 1) + return InputChains[0]; + return CurDAG->getNode(ISD::TokenFactor, ChainNodesMatched[0]->getDebugLoc(), + MVT::Other, &InputChains[0], InputChains.size()); +} + +/// MorphNode - Handle morphing a node in place for the selector. +SDNode *SelectionDAGISel:: +MorphNode(SDNode *Node, unsigned TargetOpc, SDVTList VTList, + const SDValue *Ops, unsigned NumOps, unsigned EmitNodeInfo) { + // It is possible we're using MorphNodeTo to replace a node with no + // normal results with one that has a normal result (or we could be + // adding a chain) and the input could have flags and chains as well. + // In this case we need to shifting the operands down. + // FIXME: This is a horrible hack and broken in obscure cases, no worse + // than the old isel though. We should sink this into MorphNodeTo. + int OldFlagResultNo = -1, OldChainResultNo = -1; + + unsigned NTMNumResults = Node->getNumValues(); + if (Node->getValueType(NTMNumResults-1) == MVT::Flag) { + OldFlagResultNo = NTMNumResults-1; + if (NTMNumResults != 1 && + Node->getValueType(NTMNumResults-2) == MVT::Other) + OldChainResultNo = NTMNumResults-2; + } else if (Node->getValueType(NTMNumResults-1) == MVT::Other) + OldChainResultNo = NTMNumResults-1; + + // Call the underlying SelectionDAG routine to do the transmogrification. Note + // that this deletes operands of the old node that become dead. + SDNode *Res = CurDAG->MorphNodeTo(Node, ~TargetOpc, VTList, Ops, NumOps); + + // MorphNodeTo can operate in two ways: if an existing node with the + // specified operands exists, it can just return it. Otherwise, it + // updates the node in place to have the requested operands. + if (Res == Node) { + // If we updated the node in place, reset the node ID. To the isel, + // this should be just like a newly allocated machine node. + Res->setNodeId(-1); + } + + unsigned ResNumResults = Res->getNumValues(); + // Move the flag if needed. + if ((EmitNodeInfo & OPFL_FlagOutput) && OldFlagResultNo != -1 && + (unsigned)OldFlagResultNo != ResNumResults-1) + CurDAG->ReplaceAllUsesOfValueWith(SDValue(Node, OldFlagResultNo), + SDValue(Res, ResNumResults-1)); + + if ((EmitNodeInfo & OPFL_FlagOutput) != 0) + --ResNumResults; + + // Move the chain reference if needed. + if ((EmitNodeInfo & OPFL_Chain) && OldChainResultNo != -1 && + (unsigned)OldChainResultNo != ResNumResults-1) + CurDAG->ReplaceAllUsesOfValueWith(SDValue(Node, OldChainResultNo), + SDValue(Res, ResNumResults-1)); + + // Otherwise, no replacement happened because the node already exists. Replace + // Uses of the old node with the new one. + if (Res != Node) + CurDAG->ReplaceAllUsesWith(Node, Res); + + return Res; +} + +/// CheckPatternPredicate - Implements OP_CheckPatternPredicate. +ALWAYS_INLINE static bool +CheckSame(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SDValue N, const SmallVectorImpl<SDValue> &RecordedNodes) { + // Accept if it is exactly the same as a previously recorded node. + unsigned RecNo = MatcherTable[MatcherIndex++]; + assert(RecNo < RecordedNodes.size() && "Invalid CheckSame"); + return N == RecordedNodes[RecNo]; +} + +/// CheckPatternPredicate - Implements OP_CheckPatternPredicate. +ALWAYS_INLINE static bool +CheckPatternPredicate(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SelectionDAGISel &SDISel) { + return SDISel.CheckPatternPredicate(MatcherTable[MatcherIndex++]); +} + +/// CheckNodePredicate - Implements OP_CheckNodePredicate. +ALWAYS_INLINE static bool +CheckNodePredicate(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SelectionDAGISel &SDISel, SDNode *N) { + return SDISel.CheckNodePredicate(N, MatcherTable[MatcherIndex++]); +} + +ALWAYS_INLINE static bool +CheckOpcode(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SDNode *N) { + return N->getOpcode() == MatcherTable[MatcherIndex++]; +} + +ALWAYS_INLINE static bool +CheckType(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SDValue N, const TargetLowering &TLI) { + MVT::SimpleValueType VT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++]; + if (N.getValueType() == VT) return true; + + // Handle the case when VT is iPTR. + return VT == MVT::iPTR && N.getValueType() == TLI.getPointerTy(); +} + +ALWAYS_INLINE static bool +CheckChildType(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SDValue N, const TargetLowering &TLI, + unsigned ChildNo) { + if (ChildNo >= N.getNumOperands()) + return false; // Match fails if out of range child #. + return ::CheckType(MatcherTable, MatcherIndex, N.getOperand(ChildNo), TLI); +} + + +ALWAYS_INLINE static bool +CheckCondCode(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SDValue N) { + return cast<CondCodeSDNode>(N)->get() == + (ISD::CondCode)MatcherTable[MatcherIndex++]; +} + +ALWAYS_INLINE static bool +CheckValueType(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SDValue N, const TargetLowering &TLI) { + MVT::SimpleValueType VT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++]; + if (cast<VTSDNode>(N)->getVT() == VT) + return true; + + // Handle the case when VT is iPTR. + return VT == MVT::iPTR && cast<VTSDNode>(N)->getVT() == TLI.getPointerTy(); +} + +ALWAYS_INLINE static bool +CheckInteger(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SDValue N) { + int64_t Val = MatcherTable[MatcherIndex++]; + if (Val & 128) + Val = GetVBR(Val, MatcherTable, MatcherIndex); + + ConstantSDNode *C = dyn_cast<ConstantSDNode>(N); + return C != 0 && C->getSExtValue() == Val; +} + +ALWAYS_INLINE static bool +CheckAndImm(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SDValue N, SelectionDAGISel &SDISel) { + int64_t Val = MatcherTable[MatcherIndex++]; + if (Val & 128) + Val = GetVBR(Val, MatcherTable, MatcherIndex); + + if (N->getOpcode() != ISD::AND) return false; + + ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(1)); + return C != 0 && SDISel.CheckAndMask(N.getOperand(0), C, Val); +} + +ALWAYS_INLINE static bool +CheckOrImm(const unsigned char *MatcherTable, unsigned &MatcherIndex, + SDValue N, SelectionDAGISel &SDISel) { + int64_t Val = MatcherTable[MatcherIndex++]; + if (Val & 128) + Val = GetVBR(Val, MatcherTable, MatcherIndex); + + if (N->getOpcode() != ISD::OR) return false; + + ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(1)); + return C != 0 && SDISel.CheckOrMask(N.getOperand(0), C, Val); +} + +/// IsPredicateKnownToFail - If we know how and can do so without pushing a +/// scope, evaluate the current node. If the current predicate is known to +/// fail, set Result=true and return anything. If the current predicate is +/// known to pass, set Result=false and return the MatcherIndex to continue +/// with. If the current predicate is unknown, set Result=false and return the +/// MatcherIndex to continue with. +static unsigned IsPredicateKnownToFail(const unsigned char *Table, + unsigned Index, SDValue N, + bool &Result, SelectionDAGISel &SDISel, + SmallVectorImpl<SDValue> &RecordedNodes){ + switch (Table[Index++]) { + default: + Result = false; + return Index-1; // Could not evaluate this predicate. + case SelectionDAGISel::OPC_CheckSame: + Result = !::CheckSame(Table, Index, N, RecordedNodes); + return Index; + case SelectionDAGISel::OPC_CheckPatternPredicate: + Result = !::CheckPatternPredicate(Table, Index, SDISel); + return Index; + case SelectionDAGISel::OPC_CheckPredicate: + Result = !::CheckNodePredicate(Table, Index, SDISel, N.getNode()); + return Index; + case SelectionDAGISel::OPC_CheckOpcode: + Result = !::CheckOpcode(Table, Index, N.getNode()); + return Index; + case SelectionDAGISel::OPC_CheckType: + Result = !::CheckType(Table, Index, N, SDISel.TLI); + return Index; + case SelectionDAGISel::OPC_CheckChild0Type: + case SelectionDAGISel::OPC_CheckChild1Type: + case SelectionDAGISel::OPC_CheckChild2Type: + case SelectionDAGISel::OPC_CheckChild3Type: + case SelectionDAGISel::OPC_CheckChild4Type: + case SelectionDAGISel::OPC_CheckChild5Type: + case SelectionDAGISel::OPC_CheckChild6Type: + case SelectionDAGISel::OPC_CheckChild7Type: + Result = !::CheckChildType(Table, Index, N, SDISel.TLI, + Table[Index-1] - SelectionDAGISel::OPC_CheckChild0Type); + return Index; + case SelectionDAGISel::OPC_CheckCondCode: + Result = !::CheckCondCode(Table, Index, N); + return Index; + case SelectionDAGISel::OPC_CheckValueType: + Result = !::CheckValueType(Table, Index, N, SDISel.TLI); + return Index; + case SelectionDAGISel::OPC_CheckInteger: + Result = !::CheckInteger(Table, Index, N); + return Index; + case SelectionDAGISel::OPC_CheckAndImm: + Result = !::CheckAndImm(Table, Index, N, SDISel); + return Index; + case SelectionDAGISel::OPC_CheckOrImm: + Result = !::CheckOrImm(Table, Index, N, SDISel); + return Index; + } +} + + +struct MatchScope { + /// FailIndex - If this match fails, this is the index to continue with. + unsigned FailIndex; + + /// NodeStack - The node stack when the scope was formed. + SmallVector<SDValue, 4> NodeStack; + + /// NumRecordedNodes - The number of recorded nodes when the scope was formed. + unsigned NumRecordedNodes; + + /// NumMatchedMemRefs - The number of matched memref entries. + unsigned NumMatchedMemRefs; + + /// InputChain/InputFlag - The current chain/flag + SDValue InputChain, InputFlag; + + /// HasChainNodesMatched - True if the ChainNodesMatched list is non-empty. + bool HasChainNodesMatched, HasFlagResultNodesMatched; +}; + +SDNode *SelectionDAGISel:: +SelectCodeCommon(SDNode *NodeToMatch, const unsigned char *MatcherTable, + unsigned TableSize) { + // FIXME: Should these even be selected? Handle these cases in the caller? + switch (NodeToMatch->getOpcode()) { + default: + break; + case ISD::EntryToken: // These nodes remain the same. + case ISD::BasicBlock: + case ISD::Register: + case ISD::HANDLENODE: + case ISD::TargetConstant: + case ISD::TargetConstantFP: + case ISD::TargetConstantPool: + case ISD::TargetFrameIndex: + case ISD::TargetExternalSymbol: + case ISD::TargetBlockAddress: + case ISD::TargetJumpTable: + case ISD::TargetGlobalTLSAddress: + case ISD::TargetGlobalAddress: + case ISD::TokenFactor: + case ISD::CopyFromReg: + case ISD::CopyToReg: + NodeToMatch->setNodeId(-1); // Mark selected. + return 0; + case ISD::AssertSext: + case ISD::AssertZext: + CurDAG->ReplaceAllUsesOfValueWith(SDValue(NodeToMatch, 0), + NodeToMatch->getOperand(0)); + return 0; + case ISD::INLINEASM: return Select_INLINEASM(NodeToMatch); + case ISD::EH_LABEL: return Select_EH_LABEL(NodeToMatch); + case ISD::UNDEF: return Select_UNDEF(NodeToMatch); + } + + assert(!NodeToMatch->isMachineOpcode() && "Node already selected!"); + + // Set up the node stack with NodeToMatch as the only node on the stack. + SmallVector<SDValue, 8> NodeStack; + SDValue N = SDValue(NodeToMatch, 0); + NodeStack.push_back(N); + + // MatchScopes - Scopes used when matching, if a match failure happens, this + // indicates where to continue checking. + SmallVector<MatchScope, 8> MatchScopes; + + // RecordedNodes - This is the set of nodes that have been recorded by the + // state machine. + SmallVector<SDValue, 8> RecordedNodes; + + // MatchedMemRefs - This is the set of MemRef's we've seen in the input + // pattern. + SmallVector<MachineMemOperand*, 2> MatchedMemRefs; + + // These are the current input chain and flag for use when generating nodes. + // Various Emit operations change these. For example, emitting a copytoreg + // uses and updates these. + SDValue InputChain, InputFlag; + + // ChainNodesMatched - If a pattern matches nodes that have input/output + // chains, the OPC_EmitMergeInputChains operation is emitted which indicates + // which ones they are. The result is captured into this list so that we can + // update the chain results when the pattern is complete. + SmallVector<SDNode*, 3> ChainNodesMatched; + SmallVector<SDNode*, 3> FlagResultNodesMatched; + + DEBUG(errs() << "ISEL: Starting pattern match on root node: "; + NodeToMatch->dump(CurDAG); + errs() << '\n'); + + // Determine where to start the interpreter. Normally we start at opcode #0, + // but if the state machine starts with an OPC_SwitchOpcode, then we + // accelerate the first lookup (which is guaranteed to be hot) with the + // OpcodeOffset table. + unsigned MatcherIndex = 0; + + if (!OpcodeOffset.empty()) { + // Already computed the OpcodeOffset table, just index into it. + if (N.getOpcode() < OpcodeOffset.size()) + MatcherIndex = OpcodeOffset[N.getOpcode()]; + DEBUG(errs() << " Initial Opcode index to " << MatcherIndex << "\n"); + + } else if (MatcherTable[0] == OPC_SwitchOpcode) { + // Otherwise, the table isn't computed, but the state machine does start + // with an OPC_SwitchOpcode instruction. Populate the table now, since this + // is the first time we're selecting an instruction. + unsigned Idx = 1; + while (1) { + // Get the size of this case. + unsigned CaseSize = MatcherTable[Idx++]; + if (CaseSize & 128) + CaseSize = GetVBR(CaseSize, MatcherTable, Idx); + if (CaseSize == 0) break; + + // Get the opcode, add the index to the table. + unsigned Opc = MatcherTable[Idx++]; + if (Opc >= OpcodeOffset.size()) + OpcodeOffset.resize((Opc+1)*2); + OpcodeOffset[Opc] = Idx; + Idx += CaseSize; + } + + // Okay, do the lookup for the first opcode. + if (N.getOpcode() < OpcodeOffset.size()) + MatcherIndex = OpcodeOffset[N.getOpcode()]; + } + + while (1) { + assert(MatcherIndex < TableSize && "Invalid index"); + BuiltinOpcodes Opcode = (BuiltinOpcodes)MatcherTable[MatcherIndex++]; + switch (Opcode) { + case OPC_Scope: { + // Okay, the semantics of this operation are that we should push a scope + // then evaluate the first child. However, pushing a scope only to have + // the first check fail (which then pops it) is inefficient. If we can + // determine immediately that the first check (or first several) will + // immediately fail, don't even bother pushing a scope for them. + unsigned FailIndex; + + while (1) { + unsigned NumToSkip = MatcherTable[MatcherIndex++]; + if (NumToSkip & 128) + NumToSkip = GetVBR(NumToSkip, MatcherTable, MatcherIndex); + // Found the end of the scope with no match. + if (NumToSkip == 0) { + FailIndex = 0; + break; + } + + FailIndex = MatcherIndex+NumToSkip; + + // If we can't evaluate this predicate without pushing a scope (e.g. if + // it is a 'MoveParent') or if the predicate succeeds on this node, we + // push the scope and evaluate the full predicate chain. + bool Result; + MatcherIndex = IsPredicateKnownToFail(MatcherTable, MatcherIndex, N, + Result, *this, RecordedNodes); + if (!Result) + break; + + DEBUG(errs() << " Skipped scope entry at index " << MatcherIndex + << " continuing at " << FailIndex << "\n"); + + + // Otherwise, we know that this case of the Scope is guaranteed to fail, + // move to the next case. + MatcherIndex = FailIndex; + } + + // If the whole scope failed to match, bail. + if (FailIndex == 0) break; + + // Push a MatchScope which indicates where to go if the first child fails + // to match. + MatchScope NewEntry; + NewEntry.FailIndex = FailIndex; + NewEntry.NodeStack.append(NodeStack.begin(), NodeStack.end()); + NewEntry.NumRecordedNodes = RecordedNodes.size(); + NewEntry.NumMatchedMemRefs = MatchedMemRefs.size(); + NewEntry.InputChain = InputChain; + NewEntry.InputFlag = InputFlag; + NewEntry.HasChainNodesMatched = !ChainNodesMatched.empty(); + NewEntry.HasFlagResultNodesMatched = !FlagResultNodesMatched.empty(); + MatchScopes.push_back(NewEntry); + continue; + } + case OPC_RecordNode: + // Remember this node, it may end up being an operand in the pattern. + RecordedNodes.push_back(N); + continue; + + case OPC_RecordChild0: case OPC_RecordChild1: + case OPC_RecordChild2: case OPC_RecordChild3: + case OPC_RecordChild4: case OPC_RecordChild5: + case OPC_RecordChild6: case OPC_RecordChild7: { + unsigned ChildNo = Opcode-OPC_RecordChild0; + if (ChildNo >= N.getNumOperands()) + break; // Match fails if out of range child #. + + RecordedNodes.push_back(N->getOperand(ChildNo)); + continue; + } + case OPC_RecordMemRef: + MatchedMemRefs.push_back(cast<MemSDNode>(N)->getMemOperand()); + continue; + + case OPC_CaptureFlagInput: + // If the current node has an input flag, capture it in InputFlag. + if (N->getNumOperands() != 0 && + N->getOperand(N->getNumOperands()-1).getValueType() == MVT::Flag) + InputFlag = N->getOperand(N->getNumOperands()-1); + continue; + + case OPC_MoveChild: { + unsigned ChildNo = MatcherTable[MatcherIndex++]; + if (ChildNo >= N.getNumOperands()) + break; // Match fails if out of range child #. + N = N.getOperand(ChildNo); + NodeStack.push_back(N); + continue; + } + + case OPC_MoveParent: + // Pop the current node off the NodeStack. + NodeStack.pop_back(); + assert(!NodeStack.empty() && "Node stack imbalance!"); + N = NodeStack.back(); + continue; + + case OPC_CheckSame: + if (!::CheckSame(MatcherTable, MatcherIndex, N, RecordedNodes)) break; + continue; + case OPC_CheckPatternPredicate: + if (!::CheckPatternPredicate(MatcherTable, MatcherIndex, *this)) break; + continue; + case OPC_CheckPredicate: + if (!::CheckNodePredicate(MatcherTable, MatcherIndex, *this, + N.getNode())) + break; + continue; + case OPC_CheckComplexPat: + if (!CheckComplexPattern(NodeToMatch, N, + MatcherTable[MatcherIndex++], RecordedNodes)) + break; + continue; + case OPC_CheckOpcode: + if (!::CheckOpcode(MatcherTable, MatcherIndex, N.getNode())) break; + continue; + + case OPC_CheckType: + if (!::CheckType(MatcherTable, MatcherIndex, N, TLI)) break; + continue; + + case OPC_SwitchOpcode: { + unsigned CurNodeOpcode = N.getOpcode(); + unsigned SwitchStart = MatcherIndex-1; (void)SwitchStart; + unsigned CaseSize; + while (1) { + // Get the size of this case. + CaseSize = MatcherTable[MatcherIndex++]; + if (CaseSize & 128) + CaseSize = GetVBR(CaseSize, MatcherTable, MatcherIndex); + if (CaseSize == 0) break; + + // If the opcode matches, then we will execute this case. + if (CurNodeOpcode == MatcherTable[MatcherIndex++]) + break; + + // Otherwise, skip over this case. + MatcherIndex += CaseSize; + } + + // If no cases matched, bail out. + if (CaseSize == 0) break; + + // Otherwise, execute the case we found. + DEBUG(errs() << " OpcodeSwitch from " << SwitchStart + << " to " << MatcherIndex << "\n"); + continue; + } + + case OPC_SwitchType: { + MVT::SimpleValueType CurNodeVT = N.getValueType().getSimpleVT().SimpleTy; + unsigned SwitchStart = MatcherIndex-1; (void)SwitchStart; + unsigned CaseSize; + while (1) { + // Get the size of this case. + CaseSize = MatcherTable[MatcherIndex++]; + if (CaseSize & 128) + CaseSize = GetVBR(CaseSize, MatcherTable, MatcherIndex); + if (CaseSize == 0) break; + + MVT::SimpleValueType CaseVT = + (MVT::SimpleValueType)MatcherTable[MatcherIndex++]; + if (CaseVT == MVT::iPTR) + CaseVT = TLI.getPointerTy().SimpleTy; + + // If the VT matches, then we will execute this case. + if (CurNodeVT == CaseVT) + break; + + // Otherwise, skip over this case. + MatcherIndex += CaseSize; + } + + // If no cases matched, bail out. + if (CaseSize == 0) break; + + // Otherwise, execute the case we found. + DEBUG(errs() << " TypeSwitch[" << EVT(CurNodeVT).getEVTString() + << "] from " << SwitchStart << " to " << MatcherIndex<<'\n'); + continue; + } + case OPC_CheckChild0Type: case OPC_CheckChild1Type: + case OPC_CheckChild2Type: case OPC_CheckChild3Type: + case OPC_CheckChild4Type: case OPC_CheckChild5Type: + case OPC_CheckChild6Type: case OPC_CheckChild7Type: + if (!::CheckChildType(MatcherTable, MatcherIndex, N, TLI, + Opcode-OPC_CheckChild0Type)) + break; + continue; + case OPC_CheckCondCode: + if (!::CheckCondCode(MatcherTable, MatcherIndex, N)) break; + continue; + case OPC_CheckValueType: + if (!::CheckValueType(MatcherTable, MatcherIndex, N, TLI)) break; + continue; + case OPC_CheckInteger: + if (!::CheckInteger(MatcherTable, MatcherIndex, N)) break; + continue; + case OPC_CheckAndImm: + if (!::CheckAndImm(MatcherTable, MatcherIndex, N, *this)) break; + continue; + case OPC_CheckOrImm: + if (!::CheckOrImm(MatcherTable, MatcherIndex, N, *this)) break; + continue; + + case OPC_CheckFoldableChainNode: { + assert(NodeStack.size() != 1 && "No parent node"); + // Verify that all intermediate nodes between the root and this one have + // a single use. + bool HasMultipleUses = false; + for (unsigned i = 1, e = NodeStack.size()-1; i != e; ++i) + if (!NodeStack[i].hasOneUse()) { + HasMultipleUses = true; + break; + } + if (HasMultipleUses) break; + + // Check to see that the target thinks this is profitable to fold and that + // we can fold it without inducing cycles in the graph. + if (!IsProfitableToFold(N, NodeStack[NodeStack.size()-2].getNode(), + NodeToMatch) || + !IsLegalToFold(N, NodeStack[NodeStack.size()-2].getNode(), + NodeToMatch, true/*We validate our own chains*/)) + break; + + continue; + } + case OPC_EmitInteger: { + MVT::SimpleValueType VT = + (MVT::SimpleValueType)MatcherTable[MatcherIndex++]; + int64_t Val = MatcherTable[MatcherIndex++]; + if (Val & 128) + Val = GetVBR(Val, MatcherTable, MatcherIndex); + RecordedNodes.push_back(CurDAG->getTargetConstant(Val, VT)); + continue; + } + case OPC_EmitRegister: { + MVT::SimpleValueType VT = + (MVT::SimpleValueType)MatcherTable[MatcherIndex++]; + unsigned RegNo = MatcherTable[MatcherIndex++]; + RecordedNodes.push_back(CurDAG->getRegister(RegNo, VT)); + continue; + } + + case OPC_EmitConvertToTarget: { + // Convert from IMM/FPIMM to target version. + unsigned RecNo = MatcherTable[MatcherIndex++]; + assert(RecNo < RecordedNodes.size() && "Invalid CheckSame"); + SDValue Imm = RecordedNodes[RecNo]; + + if (Imm->getOpcode() == ISD::Constant) { + int64_t Val = cast<ConstantSDNode>(Imm)->getZExtValue(); + Imm = CurDAG->getTargetConstant(Val, Imm.getValueType()); + } else if (Imm->getOpcode() == ISD::ConstantFP) { + const ConstantFP *Val=cast<ConstantFPSDNode>(Imm)->getConstantFPValue(); + Imm = CurDAG->getTargetConstantFP(*Val, Imm.getValueType()); + } + + RecordedNodes.push_back(Imm); + continue; + } + + case OPC_EmitMergeInputChains: { + assert(InputChain.getNode() == 0 && + "EmitMergeInputChains should be the first chain producing node"); + // This node gets a list of nodes we matched in the input that have + // chains. We want to token factor all of the input chains to these nodes + // together. However, if any of the input chains is actually one of the + // nodes matched in this pattern, then we have an intra-match reference. + // Ignore these because the newly token factored chain should not refer to + // the old nodes. + unsigned NumChains = MatcherTable[MatcherIndex++]; + assert(NumChains != 0 && "Can't TF zero chains"); + + assert(ChainNodesMatched.empty() && + "Should only have one EmitMergeInputChains per match"); + + // Read all of the chained nodes. + for (unsigned i = 0; i != NumChains; ++i) { + unsigned RecNo = MatcherTable[MatcherIndex++]; + assert(RecNo < RecordedNodes.size() && "Invalid CheckSame"); + ChainNodesMatched.push_back(RecordedNodes[RecNo].getNode()); + + // FIXME: What if other value results of the node have uses not matched + // by this pattern? + if (ChainNodesMatched.back() != NodeToMatch && + !RecordedNodes[RecNo].hasOneUse()) { + ChainNodesMatched.clear(); + break; + } + } + + // If the inner loop broke out, the match fails. + if (ChainNodesMatched.empty()) + break; + + // Merge the input chains if they are not intra-pattern references. + InputChain = HandleMergeInputChains(ChainNodesMatched, CurDAG); + + if (InputChain.getNode() == 0) + break; // Failed to merge. + + continue; + } + + case OPC_EmitCopyToReg: { + unsigned RecNo = MatcherTable[MatcherIndex++]; + assert(RecNo < RecordedNodes.size() && "Invalid CheckSame"); + unsigned DestPhysReg = MatcherTable[MatcherIndex++]; + + if (InputChain.getNode() == 0) + InputChain = CurDAG->getEntryNode(); + + InputChain = CurDAG->getCopyToReg(InputChain, NodeToMatch->getDebugLoc(), + DestPhysReg, RecordedNodes[RecNo], + InputFlag); + + InputFlag = InputChain.getValue(1); + continue; + } + + case OPC_EmitNodeXForm: { + unsigned XFormNo = MatcherTable[MatcherIndex++]; + unsigned RecNo = MatcherTable[MatcherIndex++]; + assert(RecNo < RecordedNodes.size() && "Invalid CheckSame"); + RecordedNodes.push_back(RunSDNodeXForm(RecordedNodes[RecNo], XFormNo)); + continue; + } + + case OPC_EmitNode: + case OPC_MorphNodeTo: { + uint16_t TargetOpc = MatcherTable[MatcherIndex++]; + TargetOpc |= (unsigned short)MatcherTable[MatcherIndex++] << 8; + unsigned EmitNodeInfo = MatcherTable[MatcherIndex++]; + // Get the result VT list. + unsigned NumVTs = MatcherTable[MatcherIndex++]; + SmallVector<EVT, 4> VTs; + for (unsigned i = 0; i != NumVTs; ++i) { + MVT::SimpleValueType VT = + (MVT::SimpleValueType)MatcherTable[MatcherIndex++]; + if (VT == MVT::iPTR) VT = TLI.getPointerTy().SimpleTy; + VTs.push_back(VT); + } + + if (EmitNodeInfo & OPFL_Chain) + VTs.push_back(MVT::Other); + if (EmitNodeInfo & OPFL_FlagOutput) + VTs.push_back(MVT::Flag); + + // This is hot code, so optimize the two most common cases of 1 and 2 + // results. + SDVTList VTList; + if (VTs.size() == 1) + VTList = CurDAG->getVTList(VTs[0]); + else if (VTs.size() == 2) + VTList = CurDAG->getVTList(VTs[0], VTs[1]); + else + VTList = CurDAG->getVTList(VTs.data(), VTs.size()); + + // Get the operand list. + unsigned NumOps = MatcherTable[MatcherIndex++]; + SmallVector<SDValue, 8> Ops; + for (unsigned i = 0; i != NumOps; ++i) { + unsigned RecNo = MatcherTable[MatcherIndex++]; + if (RecNo & 128) + RecNo = GetVBR(RecNo, MatcherTable, MatcherIndex); + + assert(RecNo < RecordedNodes.size() && "Invalid EmitNode"); + Ops.push_back(RecordedNodes[RecNo]); + } + + // If there are variadic operands to add, handle them now. + if (EmitNodeInfo & OPFL_VariadicInfo) { + // Determine the start index to copy from. + unsigned FirstOpToCopy = getNumFixedFromVariadicInfo(EmitNodeInfo); + FirstOpToCopy += (EmitNodeInfo & OPFL_Chain) ? 1 : 0; + assert(NodeToMatch->getNumOperands() >= FirstOpToCopy && + "Invalid variadic node"); + // Copy all of the variadic operands, not including a potential flag + // input. + for (unsigned i = FirstOpToCopy, e = NodeToMatch->getNumOperands(); + i != e; ++i) { + SDValue V = NodeToMatch->getOperand(i); + if (V.getValueType() == MVT::Flag) break; + Ops.push_back(V); + } + } + + // If this has chain/flag inputs, add them. + if (EmitNodeInfo & OPFL_Chain) + Ops.push_back(InputChain); + if ((EmitNodeInfo & OPFL_FlagInput) && InputFlag.getNode() != 0) + Ops.push_back(InputFlag); + + // Create the node. + SDNode *Res = 0; + if (Opcode != OPC_MorphNodeTo) { + // If this is a normal EmitNode command, just create the new node and + // add the results to the RecordedNodes list. + Res = CurDAG->getMachineNode(TargetOpc, NodeToMatch->getDebugLoc(), + VTList, Ops.data(), Ops.size()); + + // Add all the non-flag/non-chain results to the RecordedNodes list. + for (unsigned i = 0, e = VTs.size(); i != e; ++i) { + if (VTs[i] == MVT::Other || VTs[i] == MVT::Flag) break; + RecordedNodes.push_back(SDValue(Res, i)); + } + + } else { + Res = MorphNode(NodeToMatch, TargetOpc, VTList, Ops.data(), Ops.size(), + EmitNodeInfo); + } + + // If the node had chain/flag results, update our notion of the current + // chain and flag. + if (EmitNodeInfo & OPFL_FlagOutput) { + InputFlag = SDValue(Res, VTs.size()-1); + if (EmitNodeInfo & OPFL_Chain) + InputChain = SDValue(Res, VTs.size()-2); + } else if (EmitNodeInfo & OPFL_Chain) + InputChain = SDValue(Res, VTs.size()-1); + + // If the OPFL_MemRefs flag is set on this node, slap all of the + // accumulated memrefs onto it. + // + // FIXME: This is vastly incorrect for patterns with multiple outputs + // instructions that access memory and for ComplexPatterns that match + // loads. + if (EmitNodeInfo & OPFL_MemRefs) { + MachineSDNode::mmo_iterator MemRefs = + MF->allocateMemRefsArray(MatchedMemRefs.size()); + std::copy(MatchedMemRefs.begin(), MatchedMemRefs.end(), MemRefs); + cast<MachineSDNode>(Res) + ->setMemRefs(MemRefs, MemRefs + MatchedMemRefs.size()); + } + + DEBUG(errs() << " " + << (Opcode == OPC_MorphNodeTo ? "Morphed" : "Created") + << " node: "; Res->dump(CurDAG); errs() << "\n"); + + // If this was a MorphNodeTo then we're completely done! + if (Opcode == OPC_MorphNodeTo) { + // Update chain and flag uses. + UpdateChainsAndFlags(NodeToMatch, InputChain, ChainNodesMatched, + InputFlag, FlagResultNodesMatched, true); + return Res; + } + + continue; + } + + case OPC_MarkFlagResults: { + unsigned NumNodes = MatcherTable[MatcherIndex++]; + + // Read and remember all the flag-result nodes. + for (unsigned i = 0; i != NumNodes; ++i) { + unsigned RecNo = MatcherTable[MatcherIndex++]; + if (RecNo & 128) + RecNo = GetVBR(RecNo, MatcherTable, MatcherIndex); + + assert(RecNo < RecordedNodes.size() && "Invalid CheckSame"); + FlagResultNodesMatched.push_back(RecordedNodes[RecNo].getNode()); + } + continue; + } + + case OPC_CompleteMatch: { + // The match has been completed, and any new nodes (if any) have been + // created. Patch up references to the matched dag to use the newly + // created nodes. + unsigned NumResults = MatcherTable[MatcherIndex++]; + + for (unsigned i = 0; i != NumResults; ++i) { + unsigned ResSlot = MatcherTable[MatcherIndex++]; + if (ResSlot & 128) + ResSlot = GetVBR(ResSlot, MatcherTable, MatcherIndex); + + assert(ResSlot < RecordedNodes.size() && "Invalid CheckSame"); + SDValue Res = RecordedNodes[ResSlot]; + + // FIXME2: Eliminate this horrible hack by fixing the 'Gen' program + // after (parallel) on input patterns are removed. This would also + // allow us to stop encoding #results in OPC_CompleteMatch's table + // entry. + if (NodeToMatch->getNumValues() <= i || + NodeToMatch->getValueType(i) == MVT::Other || + NodeToMatch->getValueType(i) == MVT::Flag) + break; + assert((NodeToMatch->getValueType(i) == Res.getValueType() || + NodeToMatch->getValueType(i) == MVT::iPTR || + Res.getValueType() == MVT::iPTR || + NodeToMatch->getValueType(i).getSizeInBits() == + Res.getValueType().getSizeInBits()) && + "invalid replacement"); + CurDAG->ReplaceAllUsesOfValueWith(SDValue(NodeToMatch, i), Res); + } + + // If the root node defines a flag, add it to the flag nodes to update + // list. + if (NodeToMatch->getValueType(NodeToMatch->getNumValues()-1) == MVT::Flag) + FlagResultNodesMatched.push_back(NodeToMatch); + + // Update chain and flag uses. + UpdateChainsAndFlags(NodeToMatch, InputChain, ChainNodesMatched, + InputFlag, FlagResultNodesMatched, false); + + assert(NodeToMatch->use_empty() && + "Didn't replace all uses of the node?"); + + // FIXME: We just return here, which interacts correctly with SelectRoot + // above. We should fix this to not return an SDNode* anymore. + return 0; + } + } + + // If the code reached this point, then the match failed. See if there is + // another child to try in the current 'Scope', otherwise pop it until we + // find a case to check. + while (1) { + if (MatchScopes.empty()) { + CannotYetSelect(NodeToMatch); + return 0; + } + + // Restore the interpreter state back to the point where the scope was + // formed. + MatchScope &LastScope = MatchScopes.back(); + RecordedNodes.resize(LastScope.NumRecordedNodes); + NodeStack.clear(); + NodeStack.append(LastScope.NodeStack.begin(), LastScope.NodeStack.end()); + N = NodeStack.back(); + + DEBUG(errs() << " Match failed at index " << MatcherIndex + << " continuing at " << LastScope.FailIndex << "\n"); + + if (LastScope.NumMatchedMemRefs != MatchedMemRefs.size()) + MatchedMemRefs.resize(LastScope.NumMatchedMemRefs); + MatcherIndex = LastScope.FailIndex; + + InputChain = LastScope.InputChain; + InputFlag = LastScope.InputFlag; + if (!LastScope.HasChainNodesMatched) + ChainNodesMatched.clear(); + if (!LastScope.HasFlagResultNodesMatched) + FlagResultNodesMatched.clear(); + + // Check to see what the offset is at the new MatcherIndex. If it is zero + // we have reached the end of this scope, otherwise we have another child + // in the current scope to try. + unsigned NumToSkip = MatcherTable[MatcherIndex++]; + if (NumToSkip & 128) + NumToSkip = GetVBR(NumToSkip, MatcherTable, MatcherIndex); + + // If we have another child in this scope to match, update FailIndex and + // try it. + if (NumToSkip != 0) { + LastScope.FailIndex = MatcherIndex+NumToSkip; + break; + } + + // End of this scope, pop it and try the next child in the containing + // scope. + MatchScopes.pop_back(); + } + } +} + + + void SelectionDAGISel::CannotYetSelect(SDNode *N) { + if (N->getOpcode() == ISD::INTRINSIC_W_CHAIN || + N->getOpcode() == ISD::INTRINSIC_WO_CHAIN || + N->getOpcode() == ISD::INTRINSIC_VOID) + return CannotYetSelectIntrinsic(N); + std::string msg; raw_string_ostream Msg(msg); Msg << "Cannot yet select: "; |