Code refactoring, no functionality changes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105775 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2010-06-10 02:09:31 +00:00
parent aa4b5429ef
commit 302ef834e0
2 changed files with 88 additions and 84 deletions

View File

@ -128,10 +128,88 @@ 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() {
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)
return;
// Look for other loads of the same chain. Find loads that are loading from
// the same base pointer and different offsets.
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;
for (SDNode::use_iterator I = Chain->use_begin(), E = Chain->use_end();
I != E; ++I) {
SDNode *User = *I;
if (User == Node || !Visited.insert(User))
continue;
int64_t Offset1, Offset2;
if (!TII->areLoadsFromSameBasePtr(Base, User, Offset1, Offset2) ||
Offset1 == Offset2)
// FIXME: Should be ok if they addresses are identical. But earlier
// optimizations really should have eliminated one of the loads.
continue;
if (O2SMap.insert(std::make_pair(Offset1, Base)).second)
Offsets.push_back(Offset1);
O2SMap.insert(std::make_pair(Offset2, User));
Offsets.push_back(Offset2);
if (Offset2 < Offset1) {
Base = User;
BaseOffset = Offset2;
} else {
BaseOffset = Offset1;
}
Cluster = true;
}
if (!Cluster)
return;
// Sort them in increasing order.
std::sort(Offsets.begin(), Offsets.end());
// Check if the loads are close enough.
SmallVector<SDNode*, 4> Loads;
unsigned NumLoads = 0;
int64_t BaseOff = Offsets[0];
SDNode *BaseLoad = O2SMap[BaseOff];
Loads.push_back(BaseLoad);
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))
break; // Stop right here. Ignore loads that are further away.
Loads.push_back(Load);
++NumLoads;
}
if (NumLoads == 0)
return;
// Cluster loads by adding MVT::Flag outputs and inputs. This also
// ensure they are scheduled in order of increasing addresses.
SDNode *Lead = Loads[0];
AddFlags(Lead, SDValue(0,0), true, DAG);
SDValue InFlag = SDValue(Lead, Lead->getNumValues()-1);
for (unsigned i = 1, e = Loads.size(); i != e; ++i) {
bool OutFlag = i < e-1;
SDNode *Load = Loads[i];
AddFlags(Load, InFlag, OutFlag, DAG);
if (OutFlag)
InFlag = SDValue(Load, Load->getNumValues()-1);
++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;
@ -140,86 +218,9 @@ void ScheduleDAGSDNodes::ClusterNeighboringLoads() {
unsigned Opc = Node->getMachineOpcode();
const TargetInstrDesc &TID = TII->get(Opc);
if (!TID.mayLoad())
continue;
SDNode *Chain = 0;
unsigned NumOps = Node->getNumOperands();
if (Node->getOperand(NumOps-1).getValueType() == MVT::Other)
Chain = Node->getOperand(NumOps-1).getNode();
if (!Chain)
continue;
// 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();
bool Cluster = false;
SDNode *Base = Node;
int64_t BaseOffset;
for (SDNode::use_iterator I = Chain->use_begin(), E = Chain->use_end();
I != E; ++I) {
SDNode *User = *I;
if (User == Node || !Visited.insert(User))
continue;
int64_t Offset1, Offset2;
if (!TII->areLoadsFromSameBasePtr(Base, User, Offset1, Offset2) ||
Offset1 == Offset2)
// FIXME: Should be ok if they addresses are identical. But earlier
// optimizations really should have eliminated one of the loads.
continue;
if (O2SMap.insert(std::make_pair(Offset1, Base)).second)
Offsets.push_back(Offset1);
O2SMap.insert(std::make_pair(Offset2, User));
Offsets.push_back(Offset2);
if (Offset2 < Offset1) {
Base = User;
BaseOffset = Offset2;
} else {
BaseOffset = Offset1;
}
Cluster = true;
}
if (!Cluster)
continue;
// Sort them in increasing order.
std::sort(Offsets.begin(), Offsets.end());
// Check if the loads are close enough.
SmallVector<SDNode*, 4> Loads;
unsigned NumLoads = 0;
int64_t BaseOff = Offsets[0];
SDNode *BaseLoad = O2SMap[BaseOff];
Loads.push_back(BaseLoad);
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))
break; // Stop right here. Ignore loads that are further away.
Loads.push_back(Load);
++NumLoads;
}
if (NumLoads == 0)
continue;
// Cluster loads by adding MVT::Flag outputs and inputs. This also
// ensure they are scheduled in order of increasing addresses.
SDNode *Lead = Loads[0];
AddFlags(Lead, SDValue(0,0), true, DAG);
SDValue InFlag = SDValue(Lead, Lead->getNumValues()-1);
for (unsigned i = 1, e = Loads.size(); i != e; ++i) {
bool OutFlag = i < e-1;
SDNode *Load = Loads[i];
AddFlags(Load, InFlag, OutFlag, DAG);
if (OutFlag)
InFlag = SDValue(Load, Load->getNumValues()-1);
++LoadsClustered;
}
if (TID.mayLoad())
// Cluster loads from "near" addresses into combined SUnits.
ClusterNeighboringLoads(Node);
}
}
@ -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.

View File

@ -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();