De-duplicate the two implementations of ARMBaseInstrInfo::isProfitableToIfCvt() ...

Reviewers: congh, rengolin

Subscribers: aemerson, llvm-commits

Differential Revision: https://reviews.llvm.org/D30934

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297738 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/ARMBaseInstrInfo.cpp b/lib/Target/ARM/ARMBaseInstrInfo.cpp
index ca6b869..0ff01e6 100644 (file)
--- a/lib/Target/ARM/ARMBaseInstrInfo.cpp
+++ b/lib/Target/ARM/ARMBaseInstrInfo.cpp
@@ -1789,25 +1789,17 @@ isProfitableToIfCvt(MachineBasicBlock &MBB,
       }
     }
   }
-
-  // Attempt to estimate the relative costs of predication versus branching.
-  // Here we scale up each component of UnpredCost to avoid precision issue when
-  // scaling NumCycles by Probability.
-  const unsigned ScalingUpFactor = 1024;
-  unsigned UnpredCost = Probability.scale(NumCycles * ScalingUpFactor);
-  UnpredCost += ScalingUpFactor; // The branch itself
-  UnpredCost += Subtarget.getMispredictionPenalty() * ScalingUpFactor / 10;
-
-  return (NumCycles + ExtraPredCycles) * ScalingUpFactor <= UnpredCost;
+  return isProfitableToIfCvt(MBB, NumCycles, ExtraPredCycles,
+                             MBB, 0, 0, Probability);
 }
 
 bool ARMBaseInstrInfo::
-isProfitableToIfCvt(MachineBasicBlock &TMBB,
+isProfitableToIfCvt(MachineBasicBlock &,
                     unsigned TCycles, unsigned TExtra,
-                    MachineBasicBlock &FMBB,
+                    MachineBasicBlock &,
                     unsigned FCycles, unsigned FExtra,
                     BranchProbability Probability) const {
-  if (!TCycles || !FCycles)
+  if (!TCycles)
     return false;
 
   // Attempt to estimate the relative costs of predication versus branching.