Generalize PostRAHazardRecognizer so it can be used in any pass for
both forward and backward scheduling. Rename it to
ScoreboardHazardRecognizer (Scoreboard is one word). Remove integer
division from the scoreboard's critical path.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121274 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMHazardRecognizer.cpp b/lib/Target/ARM/ARMHazardRecognizer.cpp
index 317934f..b8d385b 100644
--- a/lib/Target/ARM/ARMHazardRecognizer.cpp
+++ b/lib/Target/ARM/ARMHazardRecognizer.cpp
@@ -68,14 +68,14 @@
     }
   }
 
-  return PostRAHazardRecognizer::getHazardType(SU);
+  return ScoreboardHazardRecognizer::getHazardType(SU);
 }
 
 void ARMHazardRecognizer::Reset() {
   LastMI = 0;
   Stalls = 0;
   ITBlockSize = 0;
-  PostRAHazardRecognizer::Reset();
+  ScoreboardHazardRecognizer::Reset();
 }
 
 void ARMHazardRecognizer::EmitInstruction(SUnit *SU) {
@@ -103,12 +103,16 @@
     Stalls = 0;
   }
 
-  PostRAHazardRecognizer::EmitInstruction(SU);
+  ScoreboardHazardRecognizer::EmitInstruction(SU);
 }
 
 void ARMHazardRecognizer::AdvanceCycle() {
   if (Stalls && --Stalls == 0)
     // Stalled for 4 cycles but still can't schedule any other instructions.
     LastMI = 0;
-  PostRAHazardRecognizer::AdvanceCycle();
+  ScoreboardHazardRecognizer::AdvanceCycle();
+}
+
+void ARMHazardRecognizer::RecedeCycle() {
+  llvm_unreachable("reverse ARM hazard checking unsupported");
 }