#define LLVM_CODEGEN_SCHEDULEDAG_H
#include "llvm/CodeGen/SelectionDAG.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallSet.h"
namespace llvm {
- class InstrStage;
+ struct InstrStage;
class MachineConstantPool;
- class MachineDebugInfo;
+ class MachineModuleInfo;
class MachineInstr;
class MRegisterInfo;
class SelectionDAG;
+ class SelectionDAGISel;
class SSARegMap;
class TargetInstrInfo;
class TargetInstrDescriptor;
class TargetMachine;
- class NodeInfo;
- typedef NodeInfo *NodeInfoPtr;
- typedef std::vector<NodeInfoPtr> NIVector;
- typedef std::vector<NodeInfoPtr>::iterator NIIterator;
-
-
- //===--------------------------------------------------------------------===//
- ///
- /// Node group - This struct is used to manage flagged node groups.
- ///
- class NodeGroup {
- private:
- NIVector Members; // Group member nodes
- NodeInfo *Dominator; // Node with highest latency
- unsigned Latency; // Total latency of the group
- int Pending; // Number of visits pending before
- // adding to order
-
+ /// HazardRecognizer - This determines whether or not an instruction can be
+ /// issued this cycle, and whether or not a noop needs to be inserted to handle
+ /// the hazard.
+ class HazardRecognizer {
public:
- // Ctor.
- NodeGroup() : Dominator(NULL), Pending(0) {}
-
- // Accessors
- inline void setDominator(NodeInfo *D) { Dominator = D; }
- inline NodeInfo *getDominator() { return Dominator; }
- inline void setLatency(unsigned L) { Latency = L; }
- inline unsigned getLatency() { return Latency; }
- inline int getPending() const { return Pending; }
- inline void setPending(int P) { Pending = P; }
- inline int addPending(int I) { return Pending += I; }
-
- // Pass thru
- inline bool group_empty() { return Members.empty(); }
- inline NIIterator group_begin() { return Members.begin(); }
- inline NIIterator group_end() { return Members.end(); }
- inline void group_push_back(const NodeInfoPtr &NI) {
- Members.push_back(NI);
+ virtual ~HazardRecognizer();
+
+ enum HazardType {
+ NoHazard, // This instruction can be emitted at this cycle.
+ Hazard, // This instruction can't be emitted at this cycle.
+ NoopHazard // This instruction can't be emitted, and needs noops.
+ };
+
+ /// getHazardType - Return the hazard type of emitting this node. There are
+ /// three possible results. Either:
+ /// * NoHazard: it is legal to issue this instruction on this cycle.
+ /// * Hazard: issuing this instruction would stall the machine. If some
+ /// other instruction is available, issue it first.
+ /// * NoopHazard: issuing this instruction would break the program. If
+ /// some other instruction can be issued, do so, otherwise issue a noop.
+ virtual HazardType getHazardType(SDNode *Node) {
+ return NoHazard;
}
- inline NIIterator group_insert(NIIterator Pos, const NodeInfoPtr &NI) {
- return Members.insert(Pos, NI);
+
+ /// EmitInstruction - This callback is invoked when an instruction is
+ /// emitted, to advance the hazard state.
+ virtual void EmitInstruction(SDNode *Node) {
}
- inline void group_insert(NIIterator Pos, NIIterator First,
- NIIterator Last) {
- Members.insert(Pos, First, Last);
+
+ /// AdvanceCycle - This callback is invoked when no instructions can be
+ /// issued on this cycle without a hazard. This should increment the
+ /// internal state of the hazard recognizer so that previously "Hazard"
+ /// instructions will now not be hazards.
+ virtual void AdvanceCycle() {
}
-
- static void Add(NodeInfo *D, NodeInfo *U);
- static unsigned CountInternalUses(NodeInfo *D, NodeInfo *U);
- };
-
- //===--------------------------------------------------------------------===//
- ///
- /// NodeInfo - This struct tracks information used to schedule the a node.
- ///
- class NodeInfo {
- private:
- int Pending; // Number of visits pending before
- // adding to order
- public:
- SDNode *Node; // DAG node
- InstrStage *StageBegin; // First stage in itinerary
- InstrStage *StageEnd; // Last+1 stage in itinerary
- unsigned Latency; // Total cycles to complete instr
- bool IsCall : 1; // Is function call
- bool IsLoad : 1; // Is memory load
- bool IsStore : 1; // Is memory store
- unsigned Slot; // Node's time slot
- NodeGroup *Group; // Grouping information
- unsigned VRBase; // Virtual register base
-#ifndef NDEBUG
- unsigned Preorder; // Index before scheduling
-#endif
-
- // Ctor.
- NodeInfo(SDNode *N = NULL)
- : Pending(0)
- , Node(N)
- , StageBegin(NULL)
- , StageEnd(NULL)
- , Latency(0)
- , IsCall(false)
- , Slot(0)
- , Group(NULL)
- , VRBase(0)
-#ifndef NDEBUG
- , Preorder(0)
-#endif
- {}
-
- // Accessors
- inline bool isInGroup() const {
- assert(!Group || !Group->group_empty() && "Group with no members");
- return Group != NULL;
- }
- inline bool isGroupDominator() const {
- return isInGroup() && Group->getDominator() == this;
- }
- inline int getPending() const {
- return Group ? Group->getPending() : Pending;
- }
- inline void setPending(int P) {
- if (Group) Group->setPending(P);
- else Pending = P;
- }
- inline int addPending(int I) {
- if (Group) return Group->addPending(I);
- else return Pending += I;
+
+ /// EmitNoop - This callback is invoked when a noop was added to the
+ /// instruction stream.
+ virtual void EmitNoop() {
}
};
-
- //===--------------------------------------------------------------------===//
- ///
- /// NodeGroupIterator - Iterates over all the nodes indicated by the node
- /// info. If the node is in a group then iterate over the members of the
- /// group, otherwise just the node info.
- ///
- class NodeGroupIterator {
- private:
- NodeInfo *NI; // Node info
- NIIterator NGI; // Node group iterator
- NIIterator NGE; // Node group iterator end
- public:
- // Ctor.
- NodeGroupIterator(NodeInfo *N) : NI(N) {
- // If the node is in a group then set up the group iterator. Otherwise
- // the group iterators will trip first time out.
- if (N->isInGroup()) {
- // get Group
- NodeGroup *Group = NI->Group;
- NGI = Group->group_begin();
- NGE = Group->group_end();
- // Prevent this node from being used (will be in members list
- NI = NULL;
- }
+ /// SUnit - Scheduling unit. It's an wrapper around either a single SDNode or
+ /// a group of nodes flagged together.
+ struct SUnit {
+ SDNode *Node; // Representative node.
+ SmallVector<SDNode*,4> FlaggedNodes;// All nodes flagged to Node.
+
+ // Preds/Succs - The SUnits before/after us in the graph. The boolean value
+ // is true if the edge is a token chain edge, false if it is a value edge.
+ SmallVector<std::pair<SUnit*,bool>, 4> Preds; // All sunit predecessors.
+ SmallVector<std::pair<SUnit*,bool>, 4> Succs; // All sunit successors.
+
+ typedef SmallVector<std::pair<SUnit*,bool>, 4>::iterator pred_iterator;
+ typedef SmallVector<std::pair<SUnit*,bool>, 4>::iterator succ_iterator;
+ typedef SmallVector<std::pair<SUnit*,bool>, 4>::const_iterator
+ const_pred_iterator;
+ typedef SmallVector<std::pair<SUnit*,bool>, 4>::const_iterator
+ const_succ_iterator;
+
+ short NumPreds; // # of preds.
+ short NumSuccs; // # of sucss.
+ short NumPredsLeft; // # of preds not scheduled.
+ short NumSuccsLeft; // # of succs not scheduled.
+ short NumChainPredsLeft; // # of chain preds not scheduled.
+ short NumChainSuccsLeft; // # of chain succs not scheduled.
+ bool isTwoAddress : 1; // Is a two-address instruction.
+ bool isCommutable : 1; // Is a commutable instruction.
+ bool isPending : 1; // True once pending.
+ bool isAvailable : 1; // True once available.
+ bool isScheduled : 1; // True once scheduled.
+ unsigned short Latency; // Node latency.
+ unsigned CycleBound; // Upper/lower cycle to be scheduled at.
+ unsigned Cycle; // Once scheduled, the cycle of the op.
+ unsigned Depth; // Node depth;
+ unsigned Height; // Node height;
+ unsigned NodeNum; // Entry # of node in the node vector.
+
+ SUnit(SDNode *node, unsigned nodenum)
+ : Node(node), NumPreds(0), NumSuccs(0), NumPredsLeft(0), NumSuccsLeft(0),
+ NumChainPredsLeft(0), NumChainSuccsLeft(0),
+ isTwoAddress(false), isCommutable(false),
+ isPending(false), isAvailable(false), isScheduled(false),
+ Latency(0), CycleBound(0), Cycle(0), Depth(0), Height(0),
+ NodeNum(nodenum) {}
+
+ /// addPred - This adds the specified node as a pred of the current node if
+ /// not already. This returns true if this is a new pred.
+ bool addPred(SUnit *N, bool isChain) {
+ for (unsigned i = 0, e = Preds.size(); i != e; ++i)
+ if (Preds[i].first == N && Preds[i].second == isChain)
+ return false;
+ Preds.push_back(std::make_pair(N, isChain));
+ return true;
}
-
- /// next - Return the next node info, otherwise NULL.
- ///
- NodeInfo *next() {
- // If members list
- if (NGI != NGE) return *NGI++;
- // Use node as the result (may be NULL)
- NodeInfo *Result = NI;
- // Only use once
- NI = NULL;
- // Return node or NULL
- return Result;
+
+ /// addSucc - This adds the specified node as a succ of the current node if
+ /// not already. This returns true if this is a new succ.
+ bool addSucc(SUnit *N, bool isChain) {
+ for (unsigned i = 0, e = Succs.size(); i != e; ++i)
+ if (Succs[i].first == N && Succs[i].second == isChain)
+ return false;
+ Succs.push_back(std::make_pair(N, isChain));
+ return true;
}
+
+ void dump(const SelectionDAG *G) const;
+ void dumpAll(const SelectionDAG *G) const;
};
- //===--------------------------------------------------------------------===//
-
//===--------------------------------------------------------------------===//
- ///
- /// NodeGroupOpIterator - Iterates over all the operands of a node. If the
- /// node is a member of a group, this iterates over all the operands of all
- /// the members of the group.
- ///
- class NodeGroupOpIterator {
- private:
- NodeInfo *NI; // Node containing operands
- NodeGroupIterator GI; // Node group iterator
- SDNode::op_iterator OI; // Operand iterator
- SDNode::op_iterator OE; // Operand iterator end
-
- /// CheckNode - Test if node has more operands. If not get the next node
- /// skipping over nodes that have no operands.
- void CheckNode() {
- // Only if operands are exhausted first
- while (OI == OE) {
- // Get next node info
- NodeInfo *NI = GI.next();
- // Exit if nodes are exhausted
- if (!NI) return;
- // Get node itself
- SDNode *Node = NI->Node;
- // Set up the operand iterators
- OI = Node->op_begin();
- OE = Node->op_end();
- }
- }
-
+ /// SchedulingPriorityQueue - This interface is used to plug different
+ /// priorities computation algorithms into the list scheduler. It implements
+ /// the interface of a standard priority queue, where nodes are inserted in
+ /// arbitrary order and returned in priority order. The computation of the
+ /// priority and the representation of the queue are totally up to the
+ /// implementation to decide.
+ ///
+ class SchedulingPriorityQueue {
public:
- // Ctor.
- NodeGroupOpIterator(NodeInfo *N)
- : NI(N), GI(N), OI(SDNode::op_iterator()), OE(SDNode::op_iterator()) {}
+ virtual ~SchedulingPriorityQueue() {}
- /// isEnd - Returns true when not more operands are available.
- ///
- inline bool isEnd() { CheckNode(); return OI == OE; }
+ virtual void initNodes(DenseMap<SDNode*, SUnit*> &SUMap,
+ std::vector<SUnit> &SUnits) = 0;
+ virtual void releaseState() = 0;
- /// next - Returns the next available operand.
- ///
- inline SDOperand next() {
- assert(OI != OE &&
- "Not checking for end of NodeGroupOpIterator correctly");
- return *OI++;
- }
+ virtual bool empty() const = 0;
+ virtual void push(SUnit *U) = 0;
+
+ virtual void push_all(const std::vector<SUnit *> &Nodes) = 0;
+ virtual SUnit *pop() = 0;
+
+ /// ScheduledNode - As each node is scheduled, this method is invoked. This
+ /// allows the priority function to adjust the priority of node that have
+ /// already been emitted.
+ virtual void ScheduledNode(SUnit *Node) {}
};
class ScheduleDAG {
const MRegisterInfo *MRI; // Target processor register info
SSARegMap *RegMap; // Virtual/real register map
MachineConstantPool *ConstPool; // Target constant pool
- std::map<SDNode *, NodeInfo *> Map; // Map nodes to info
+ std::vector<SUnit*> Sequence; // The schedule. Null SUnit*'s
+ // represent noop instructions.
+ DenseMap<SDNode*, SUnit*> SUnitMap; // SDNode to SUnit mapping (n -> 1).
+ std::vector<SUnit> SUnits; // The scheduling units.
+ SmallSet<SDNode*, 16> CommuteSet; // Nodes the should be commuted.
ScheduleDAG(SelectionDAG &dag, MachineBasicBlock *bb,
const TargetMachine &tm)
: DAG(dag), BB(bb), TM(tm) {}
- virtual ~ScheduleDAG() {};
+ virtual ~ScheduleDAG() {}
/// Run - perform scheduling.
///
MachineBasicBlock *Run();
- /// getNI - Returns the node info for the specified node.
+ /// isPassiveNode - Return true if the node is a non-scheduled leaf.
///
- NodeInfo *getNI(SDNode *Node) { return Map[Node]; }
-
- /// getVR - Returns the virtual register number of the node.
+ static bool isPassiveNode(SDNode *Node) {
+ if (isa<ConstantSDNode>(Node)) return true;
+ if (isa<RegisterSDNode>(Node)) return true;
+ if (isa<GlobalAddressSDNode>(Node)) return true;
+ if (isa<BasicBlockSDNode>(Node)) return true;
+ if (isa<FrameIndexSDNode>(Node)) return true;
+ if (isa<ConstantPoolSDNode>(Node)) return true;
+ if (isa<JumpTableSDNode>(Node)) return true;
+ if (isa<ExternalSymbolSDNode>(Node)) return true;
+ return false;
+ }
+
+ /// NewSUnit - Creates a new SUnit and return a ptr to it.
///
- unsigned getVR(SDOperand Op) {
- NodeInfo *NI = getNI(Op.Val);
- assert(NI->VRBase != 0 && "Node emitted out of order - late");
- return NI->VRBase + Op.ResNo;
+ SUnit *NewSUnit(SDNode *N) {
+ SUnits.push_back(SUnit(N, SUnits.size()));
+ return &SUnits.back();
}
- void EmitNode(NodeInfo *NI);
+ /// BuildSchedUnits - Build SUnits from the selection dag that we are input.
+ /// This SUnit graph is similar to the SelectionDAG, but represents flagged
+ /// together nodes with a single SUnit.
+ void BuildSchedUnits();
- virtual void Schedule() {};
+ /// CalculateDepths, CalculateHeights - Calculate node depth / height.
+ ///
+ void CalculateDepths();
+ void CalculateHeights();
+
+ /// CountResults - The results of target nodes have register or immediate
+ /// operands first, then an optional chain, and optional flag operands
+ /// (which do not go into the machine instrs.)
+ static unsigned CountResults(SDNode *Node);
- virtual void print(std::ostream &O) const {};
+ /// CountOperands The inputs to target nodes have any actual inputs first,
+ /// followed by an optional chain operand, then flag operands. Compute the
+ /// number of actual operands that will go into the machine instr.
+ static unsigned CountOperands(SDNode *Node);
- void dump(const char *tag) const;
+ /// EmitNode - Generate machine code for an node and needed dependencies.
+ /// VRBaseMap contains, for each already emitted node, the first virtual
+ /// register number for the results of the node.
+ ///
+ void EmitNode(SDNode *Node, DenseMap<SDNode*, unsigned> &VRBaseMap);
+
+ /// EmitNoop - Emit a noop instruction.
+ ///
+ void EmitNoop();
+
+ void EmitSchedule();
- void dump() const;
+ void dumpSchedule() const;
+
+ /// Schedule - Order nodes according to selected style.
+ ///
+ virtual void Schedule() {}
private:
- unsigned CreateVirtualRegisters(MachineInstr *MI,
- unsigned NumResults,
- const TargetInstrDescriptor &II);
+ void AddOperand(MachineInstr *MI, SDOperand Op, unsigned IIOpNum,
+ const TargetInstrDescriptor *II,
+ DenseMap<SDNode*, unsigned> &VRBaseMap);
};
- /// createSimpleDAGScheduler - This creates a simple two pass instruction
+ /// createBFS_DAGScheduler - This creates a simple breadth first instruction
/// scheduler.
- ScheduleDAG* createSimpleDAGScheduler(SelectionDAG &DAG,
+ ScheduleDAG *createBFS_DAGScheduler(SelectionDAGISel *IS,
+ SelectionDAG *DAG,
+ MachineBasicBlock *BB);
+
+ /// createSimpleDAGScheduler - This creates a simple two pass instruction
+ /// scheduler using instruction itinerary.
+ ScheduleDAG* createSimpleDAGScheduler(SelectionDAGISel *IS,
+ SelectionDAG *DAG,
+ MachineBasicBlock *BB);
+
+ /// createNoItinsDAGScheduler - This creates a simple two pass instruction
+ /// scheduler without using instruction itinerary.
+ ScheduleDAG* createNoItinsDAGScheduler(SelectionDAGISel *IS,
+ SelectionDAG *DAG,
+ MachineBasicBlock *BB);
+
+ /// createBURRListDAGScheduler - This creates a bottom up register usage
+ /// reduction list scheduler.
+ ScheduleDAG* createBURRListDAGScheduler(SelectionDAGISel *IS,
+ SelectionDAG *DAG,
+ MachineBasicBlock *BB);
+
+ /// createTDRRListDAGScheduler - This creates a top down register usage
+ /// reduction list scheduler.
+ ScheduleDAG* createTDRRListDAGScheduler(SelectionDAGISel *IS,
+ SelectionDAG *DAG,
+ MachineBasicBlock *BB);
+
+ /// createTDListDAGScheduler - This creates a top-down list scheduler with
+ /// a hazard recognizer.
+ ScheduleDAG* createTDListDAGScheduler(SelectionDAGISel *IS,
+ SelectionDAG *DAG,
MachineBasicBlock *BB);
+
+ /// createDefaultScheduler - This creates an instruction scheduler appropriate
+ /// for the target.
+ ScheduleDAG* createDefaultScheduler(SelectionDAGISel *IS,
+ SelectionDAG *DAG,
+ MachineBasicBlock *BB);
}
#endif