Factor out scoreboard into separate class. This way we might have several different score boards.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100644 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 70 insertions, 58 deletions

diff --git a/lib/CodeGen/ExactHazardRecognizer.cpp b/lib/CodeGen/ExactHazardRecognizer.cpp
index 61959bb..52908ed 100644
--- a/lib/CodeGen/ExactHazardRecognizer.cpp
+++ b/lib/CodeGen/ExactHazardRecognizer.cpp
@@ -29,7 +29,7 @@ ExactHazardRecognizer(const InstrItineraryData &LItinData) :
   // Determine the maximum depth of any itinerary. This determines the
   // depth of the scoreboard. We always make the scoreboard at least 1
   // cycle deep to avoid dealing with the boundary condition.
-  ScoreboardDepth = 1;
+  unsigned ScoreboardDepth = 1;
   if (!ItinData.isEmpty()) {
     for (unsigned idx = 0; ; ++idx) {
       if (ItinData.isEndMarker(idx))
@@ -45,35 +45,25 @@ ExactHazardRecognizer(const InstrItineraryData &LItinData) :
     }
   }
 
-  Scoreboard = new unsigned[ScoreboardDepth];
-  ScoreboardHead = 0;
+  Scoreboard.reset(ScoreboardDepth);
 
   DEBUG(dbgs() << "Using exact hazard recognizer: ScoreboardDepth = " 
                << ScoreboardDepth << '\n');
 }
 
-ExactHazardRecognizer::~ExactHazardRecognizer() {
-  delete [] Scoreboard;
-}
-
 void ExactHazardRecognizer::Reset() {
-  memset(Scoreboard, 0, ScoreboardDepth * sizeof(unsigned));
-  ScoreboardHead = 0;
-}
-
-unsigned ExactHazardRecognizer::getFutureIndex(unsigned offset) {
-  return (ScoreboardHead + offset) % ScoreboardDepth;
+  Scoreboard.reset();
 }
 
-void ExactHazardRecognizer::dumpScoreboard() {
+void ExactHazardRecognizer::ScoreBoard::dump() const {
   dbgs() << "Scoreboard:\n";
-  
-  unsigned last = ScoreboardDepth - 1;
-  while ((last > 0) && (Scoreboard[getFutureIndex(last)] == 0))
+
+  unsigned last = Depth - 1;
+  while ((last > 0) && ((*this)[last] == 0))
     last--;
 
   for (unsigned i = 0; i <= last; i++) {
-    unsigned FUs = Scoreboard[getFutureIndex(i)];
+    unsigned FUs = (*this)[i];
     dbgs() << "\t";
     for (int j = 31; j >= 0; j--)
       dbgs() << ((FUs & (1 << j)) ? '1' : '0');
@@ -96,11 +86,10 @@ ExactHazardRecognizer::HazardType ExactHazardRecognizer::getHazardType(SUnit *SU
     // stage is occupied. FIXME it would be more accurate to find the
     // same unit free in all the cycles.
     for (unsigned int i = 0; i < IS->getCycles(); ++i) {
-      assert(((cycle + i) < ScoreboardDepth) && 
+      assert(((cycle + i) < Scoreboard.getDepth()) &&
              "Scoreboard depth exceeded!");
-      
-      unsigned index = getFutureIndex(cycle + i);
-      unsigned freeUnits = IS->getUnits() & ~Scoreboard[index];
+
+      unsigned freeUnits = IS->getUnits() & ~Scoreboard[cycle + i];
       if (!freeUnits) {
         DEBUG(dbgs() << "*** Hazard in cycle " << (cycle + i) << ", ");
         DEBUG(dbgs() << "SU(" << SU->NodeNum << "): ");
@@ -108,14 +97,14 @@ ExactHazardRecognizer::HazardType ExactHazardRecognizer::getHazardType(SUnit *SU
         return Hazard;
       }
     }
-    
+
     // Advance the cycle to the next stage.
     cycle += IS->getNextCycles();
   }
 
   return NoHazard;
 }
-    
+
 void ExactHazardRecognizer::EmitInstruction(SUnit *SU) {
   if (ItinData.isEmpty())
     return;
@@ -131,31 +120,30 @@ void ExactHazardRecognizer::EmitInstruction(SUnit *SU) {
     // stage is occupied. FIXME it would be more accurate to reserve
     // the same unit free in all the cycles.
     for (unsigned int i = 0; i < IS->getCycles(); ++i) {
-      assert(((cycle + i) < ScoreboardDepth) &&
+      assert(((cycle + i) < Scoreboard.getDepth()) &&
              "Scoreboard depth exceeded!");
-      
-      unsigned index = getFutureIndex(cycle + i);
-      unsigned freeUnits = IS->getUnits() & ~Scoreboard[index];
-      
+
+      unsigned freeUnits = IS->getUnits() & ~Scoreboard[cycle + i];
+
       // reduce to a single unit
       unsigned freeUnit = 0;
       do {
         freeUnit = freeUnits;
         freeUnits = freeUnit & (freeUnit - 1);
       } while (freeUnits);
-      
+
       assert(freeUnit && "No function unit available!");
-      Scoreboard[index] |= freeUnit;
+      Scoreboard[cycle + i] |= freeUnit;
     }
-    
+
     // Advance the cycle to the next stage.
     cycle += IS->getNextCycles();
   }
-  
-  DEBUG(dumpScoreboard());
+
+  DEBUG(Scoreboard.dump());
 }
-    
+
 void ExactHazardRecognizer::AdvanceCycle() {
-  Scoreboard[ScoreboardHead] = 0;
-  ScoreboardHead = getFutureIndex(1);
+  Scoreboard[0] = 0;
+  Scoreboard.advance();
 }
diff --git a/lib/CodeGen/ExactHazardRecognizer.h b/lib/CodeGen/ExactHazardRecognizer.h
index 71ac979..50fe024 100644
--- a/lib/CodeGen/ExactHazardRecognizer.h
+++ b/lib/CodeGen/ExactHazardRecognizer.h
@@ -22,35 +22,59 @@
 
 namespace llvm {
   class ExactHazardRecognizer : public ScheduleHazardRecognizer {
-    // Itinerary data for the target.
-    const InstrItineraryData &ItinData;
-
-    // Scoreboard to track function unit usage. Scoreboard[0] is a
+    // ScoreBoard to track function unit usage. ScoreBoard[0] is a
     // mask of the FUs in use in the cycle currently being
-    // schedule. Scoreboard[1] is a mask for the next cycle. The
-    // Scoreboard is used as a circular buffer with the current cycle
-    // indicated by ScoreboardHead.
-    unsigned *Scoreboard;
+    // schedule. ScoreBoard[1] is a mask for the next cycle. The
+    // ScoreBoard is used as a circular buffer with the current cycle
+    // indicated by Head.
+    class ScoreBoard {
+      unsigned *Data;
+
+      // The maximum number of cycles monitored by the Scoreboard. This
+      // value is determined based on the target itineraries to ensure
+      // that all hazards can be tracked.
+      size_t Depth;
+      // Indices into the Scoreboard that represent the current cycle.
+      size_t Head;
+    public:
+      ScoreBoard():Data(NULL), Depth(0), Head(0) { }
+      ~ScoreBoard() {
+        delete[] Data;
+      }
+
+      size_t getDepth() const { return Depth; }
+      unsigned& operator[](size_t idx) const {
+        assert(Depth && "ScoreBoard was not initialized properly!");
+
+        return Data[(Head + idx) % Depth];
+      }
 
-    // The maximum number of cycles monitored by the Scoreboard. This
-    // value is determined based on the target itineraries to ensure
-    // that all hazards can be tracked.
-    unsigned ScoreboardDepth;
+      void reset(size_t d = 1) {
+        if (Data == NULL) {
+          Depth = d;
+          Data = new unsigned[Depth];
+        }
 
-    // Indices into the Scoreboard that represent the current cycle.
-    unsigned ScoreboardHead;
+        memset(Data, 0, Depth * sizeof(Data[0]));
+        Head = 0;
+      }
 
-    // Return the scoreboard index to use for 'offset' cycles in the
-    // future. 'offset' of 0 returns ScoreboardHead.
-    unsigned getFutureIndex(unsigned offset);
+      void advance() {
+        Head = (Head + 1) % Depth;
+      }
 
-    // Print the scoreboard.
-    void dumpScoreboard();
+      // Print the scoreboard.
+      void dump() const;
+    };
+
+    // Itinerary data for the target.
+    const InstrItineraryData &ItinData;
+
+    ScoreBoard Scoreboard;
 
   public:
     ExactHazardRecognizer(const InstrItineraryData &ItinData);
-    ~ExactHazardRecognizer();
-    
+
     virtual HazardType getHazardType(SUnit *SU);
     virtual void Reset();
     virtual void EmitInstruction(SUnit *SU);