Code refactoring, no functionality changes.

llvm-svn: 105775

lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp

@@ -128,33 +128,19 @@ static void AddFlags(SDNode *N, SDValue Flag, bool AddFlag,
 /// offsets are not far apart (target specific), it add MVT::Flag inputs and
 /// outputs to ensure they are scheduled together and in order. This
 /// optimization may benefit some targets by improving cache locality.
-void ScheduleDAGSDNodes::ClusterNeighboringLoads() {
-  SmallPtrSet<SDNode*, 16> Visited;
-  SmallVector<int64_t, 4> Offsets;
-  DenseMap<long long, SDNode*> O2SMap;  // Map from offset to SDNode.
-  for (SelectionDAG::allnodes_iterator NI = DAG->allnodes_begin(),
-       E = DAG->allnodes_end(); NI != E; ++NI) {
-    SDNode *Node = &*NI;
-    if (!Node || !Node->isMachineOpcode())
-      continue;
-
-    unsigned Opc = Node->getMachineOpcode();
-    const TargetInstrDesc &TID = TII->get(Opc);
-    if (!TID.mayLoad())
-      continue;
-
+void ScheduleDAGSDNodes::ClusterNeighboringLoads(SDNode *Node) {
   SDNode *Chain = 0;
   unsigned NumOps = Node->getNumOperands();
   if (Node->getOperand(NumOps-1).getValueType() == MVT::Other)
     Chain = Node->getOperand(NumOps-1).getNode();
   if (!Chain)
-      continue;
+    return;
 
   // Look for other loads of the same chain. Find loads that are loading from
   // the same base pointer and different offsets.
-    Visited.clear();
-    Offsets.clear();
-    O2SMap.clear();
+  SmallPtrSet<SDNode*, 16> Visited;
+  SmallVector<int64_t, 4> Offsets;
+  DenseMap<long long, SDNode*> O2SMap;  // Map from offset to SDNode.
   bool Cluster = false;
   SDNode *Base = Node;
   int64_t BaseOffset;
@@ -183,7 +169,7 @@ void ScheduleDAGSDNodes::ClusterNeighboringLoads() {
   }
 
   if (!Cluster)
-      continue;
+    return;
 
   // Sort them in increasing order.
   std::sort(Offsets.begin(), Offsets.end());
@@ -197,15 +183,14 @@ void ScheduleDAGSDNodes::ClusterNeighboringLoads() {
   for (unsigned i = 1, e = Offsets.size(); i != e; ++i) {
     int64_t Offset = Offsets[i];
     SDNode *Load = O2SMap[Offset];
-      if (!TII->shouldScheduleLoadsNear(BaseLoad, Load, BaseOff, Offset,
-                                        NumLoads))
+    if (!TII->shouldScheduleLoadsNear(BaseLoad, Load, BaseOff, Offset,NumLoads))
       break; // Stop right here. Ignore loads that are further away.
     Loads.push_back(Load);
     ++NumLoads;
   }
 
   if (NumLoads == 0)
-      continue;
+    return;
 
   // Cluster loads by adding MVT::Flag outputs and inputs. This also
   // ensure they are scheduled in order of increasing addresses.
@@ -221,6 +206,22 @@ void ScheduleDAGSDNodes::ClusterNeighboringLoads() {
     ++LoadsClustered;
   }
 }
+
+/// ClusterNodes - Cluster certain nodes which should be scheduled together.
+///
+void ScheduleDAGSDNodes::ClusterNodes() {
+  for (SelectionDAG::allnodes_iterator NI = DAG->allnodes_begin(),
+       E = DAG->allnodes_end(); NI != E; ++NI) {
+    SDNode *Node = &*NI;
+    if (!Node || !Node->isMachineOpcode())
+      continue;
+
+    unsigned Opc = Node->getMachineOpcode();
+    const TargetInstrDesc &TID = TII->get(Opc);
+    if (TID.mayLoad())
+      // Cluster loads from "near" addresses into combined SUnits.
+      ClusterNeighboringLoads(Node);
+  }
 }
 
 void ScheduleDAGSDNodes::BuildSchedUnits() {
@@ -388,8 +389,8 @@ void ScheduleDAGSDNodes::AddSchedEdges() {
 /// excludes nodes that aren't interesting to scheduling, and represents
 /// flagged together nodes with a single SUnit.
 void ScheduleDAGSDNodes::BuildSchedGraph(AliasAnalysis *AA) {
-  // Cluster loads from "near" addresses into combined SUnits.
-  ClusterNeighboringLoads();
+  // Cluster certain nodes which should be scheduled together.
+  ClusterNodes();
   // Populate the SUnits array.
   BuildSchedUnits();
   // Compute all the scheduling dependencies between nodes.

lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.h

@@ -108,7 +108,10 @@ namespace llvm {
   private:
     /// ClusterNeighboringLoads - Cluster loads from "near" addresses into
     /// combined SUnits.
-    void ClusterNeighboringLoads();
+    void ClusterNeighboringLoads(SDNode *Node);
+    /// ClusterNodes - Cluster certain nodes which should be scheduled together.
+    ///
+    void ClusterNodes();
 
     /// BuildSchedUnits, AddSchedEdges - Helper functions for BuildSchedGraph.
     void BuildSchedUnits();