R600: Use depth first scheduling algorithm

It should increase PV substitution opportunities and lower gpr
usage (pending computations path are "flushed" sooner)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182128 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 27 deletions

diff --git a/lib/Target/R600/R600MachineScheduler.h b/lib/Target/R600/R600MachineScheduler.h
index 3d0367fd8e..c82ee49c78 100644
--- a/lib/Target/R600/R600MachineScheduler.h
+++ b/lib/Target/R600/R600MachineScheduler.h
@@ -24,13 +24,6 @@ using namespace llvm;
 
 namespace llvm {
 
-class CompareSUnit {
-public:
-  bool operator()(const SUnit *S1, const SUnit *S2) {
-    return S1->getDepth() > S2->getDepth();
-  }
-};
-
 class R600SchedStrategy : public MachineSchedStrategy {
 
   const ScheduleDAGMI *DAG;
@@ -38,12 +31,6 @@ class R600SchedStrategy : public MachineSchedStrategy {
   const R600RegisterInfo *TRI;
   MachineRegisterInfo *MRI;
 
-  enum InstQueue {
-    QAlu = 1,
-    QFetch = 2,
-    QOther = 4
-  };
-
   enum InstKind {
     IDAlu,
     IDFetch,
@@ -62,8 +49,9 @@ class R600SchedStrategy : public MachineSchedStrategy {
     AluLast
   };
 
-  ReadyQueue *Available[IDLast], *Pending[IDLast];
-  std::multiset<SUnit *, CompareSUnit> AvailableAlus[AluLast];
+  std::vector<SUnit *> Available[IDLast], Pending[IDLast];
+  std::vector<SUnit *> AvailableAlus[AluLast];
+  std::vector<SUnit *> FakeCopy;
 
   InstKind CurInstKind;
   int CurEmitted;
@@ -76,19 +64,9 @@ class R600SchedStrategy : public MachineSchedStrategy {
 public:
   R600SchedStrategy() :
     DAG(0), TII(0), TRI(0), MRI(0) {
-    Available[IDAlu] = new ReadyQueue(QAlu, "AAlu");
-    Available[IDFetch] = new ReadyQueue(QFetch, "AFetch");
-    Available[IDOther] = new ReadyQueue(QOther, "AOther");
-    Pending[IDAlu] = new ReadyQueue(QAlu<<4, "PAlu");
-    Pending[IDFetch] = new ReadyQueue(QFetch<<4, "PFetch");
-    Pending[IDOther] = new ReadyQueue(QOther<<4, "POther");
   }
 
   virtual ~R600SchedStrategy() {
-    for (unsigned I = 0; I < IDLast; ++I) {
-      delete Available[I];
-      delete Pending[I];
-    }
   }
 
   virtual void initialize(ScheduleDAGMI *dag);
@@ -107,12 +85,12 @@ private:
   bool isAvailablesAluEmpty() const;
   SUnit *AttemptFillSlot (unsigned Slot);
   void PrepareNextSlot();
-  SUnit *PopInst(std::multiset<SUnit *, CompareSUnit> &Q);
+  SUnit *PopInst(std::vector<SUnit*> &Q);
 
   void AssignSlot(MachineInstr *MI, unsigned Slot);
   SUnit* pickAlu();
   SUnit* pickOther(int QID);
-  void MoveUnits(ReadyQueue *QSrc, ReadyQueue *QDst);
+  void MoveUnits(std::vector<SUnit *> &QSrc, std::vector<SUnit *> &QDst);
 };
 
 } // namespace llvm