X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FExactHazardRecognizer.cpp;h=af5f2892c2f07f2f1a56321e96688b4037688308;hb=95c57ea1825fedc10dc2a311b0d97105f6e61148;hp=266c74c9995ed542180b3a3d1e2cf1126e058d41;hpb=73242dd692c0226073c367c2fe573287a3d63fc1;p=oota-llvm.git

diff --git a/lib/CodeGen/ExactHazardRecognizer.cpp b/lib/CodeGen/ExactHazardRecognizer.cpp
index 266c74c9995..af5f2892c2f 100644
--- a/lib/CodeGen/ExactHazardRecognizer.cpp
+++ b/lib/CodeGen/ExactHazardRecognizer.cpp
@@ -7,7 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// This implements a a hazard recognizer using the instructions itineraries
+// This implements a hazard recognizer using the instructions itineraries
 // defined for the current target.
 //
 //===----------------------------------------------------------------------===//
@@ -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 +45,27 @@ ExactHazardRecognizer(const InstrItineraryData &LItinData) :
     }
   }
 
-  Scoreboard = new unsigned[ScoreboardDepth];
-  ScoreboardHead = 0;
+  ReservedScoreboard.reset(ScoreboardDepth);
+  RequiredScoreboard.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;
+  RequiredScoreboard.reset();
+  ReservedScoreboard.reset();
 }
 
-unsigned ExactHazardRecognizer::getFutureIndex(unsigned offset) {
-  return (ScoreboardHead + offset) % ScoreboardDepth;
-}
-
-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 +88,23 @@ 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) < RequiredScoreboard.getDepth()) &&
              "Scoreboard depth exceeded!");
-      
-      unsigned index = getFutureIndex(cycle + i);
-      unsigned freeUnits = IS->getUnits() & ~Scoreboard[index];
+
+      unsigned freeUnits = IS->getUnits();
+      switch (IS->getReservationKind()) {
+      default:
+       assert(0 && "Invalid FU reservation");
+      case InstrStage::Required:
+        // Required FUs conflict with both reserved and required ones
+        freeUnits &= ~ReservedScoreboard[cycle + i];
+        // FALLTHROUGH
+      case InstrStage::Reserved:
+        // Reserved FUs can conflict only with required ones.
+        freeUnits &= ~RequiredScoreboard[cycle + i];
+        break;
+      }
+
       if (!freeUnits) {
         DEBUG(dbgs() << "*** Hazard in cycle " << (cycle + i) << ", ");
         DEBUG(dbgs() << "SU(" << SU->NodeNum << "): ");
@@ -108,14 +112,14 @@ 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;
@@ -125,37 +129,52 @@ void ExactHazardRecognizer::EmitInstruction(SUnit *SU) {
   // Use the itinerary for the underlying instruction to reserve FU's
   // in the scoreboard at the appropriate future cycles.
   unsigned idx = SU->getInstr()->getDesc().getSchedClass();
-  for (const InstrStage *IS = ItinData.beginStage(idx), 
+  for (const InstrStage *IS = ItinData.beginStage(idx),
          *E = ItinData.endStage(idx); IS != E; ++IS) {
     // We must reserve one of the stage's units for every cycle the
     // 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) < RequiredScoreboard.getDepth()) &&
              "Scoreboard depth exceeded!");
-      
-      unsigned index = getFutureIndex(cycle + i);
-      unsigned freeUnits = IS->getUnits() & ~Scoreboard[index];
-      
+
+      unsigned freeUnits = IS->getUnits();
+      switch (IS->getReservationKind()) {
+      default:
+       assert(0 && "Invalid FU reservation");
+      case InstrStage::Required:
+        // Required FUs conflict with both reserved and required ones
+        freeUnits &= ~ReservedScoreboard[cycle + i];
+        // FALLTHROUGH
+      case InstrStage::Reserved:
+        // Reserved FUs can conflict only with required ones.
+        freeUnits &= ~RequiredScoreboard[cycle + i];
+        break;
+      }
+
       // 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;
+      if (IS->getReservationKind() == InstrStage::Required)
+        RequiredScoreboard[cycle + i] |= freeUnit;
+      else
+        ReservedScoreboard[cycle + i] |= freeUnit;
     }
-    
+
     // Advance the cycle to the next stage.
     cycle += IS->getNextCycles();
   }
-  
-  DEBUG(dumpScoreboard());
+
+  DEBUG(ReservedScoreboard.dump());
+  DEBUG(RequiredScoreboard.dump());
 }
-    
+
 void ExactHazardRecognizer::AdvanceCycle() {
-  Scoreboard[ScoreboardHead] = 0;
-  ScoreboardHead = getFutureIndex(1);
+  ReservedScoreboard[0] = 0; ReservedScoreboard.advance();
+  RequiredScoreboard[0] = 0; RequiredScoreboard.advance();
 }