[llvm] r216141 - [LoopVectorize] Up the maximum unroll factor to 4 for AArch64

[James Molloy]

Author: jamesm
Date: Wed Aug 20 19:02:51 2014
New Revision: 216141

URL: http://llvm.org/viewvc/llvm-project?rev=216141&view=rev
Log:
[LoopVectorize] Up the maximum unroll factor to 4 for AArch64

Only for Cortex-A57 and Cyclone for now, where it has shown wins.


Modified:
    llvm/trunk/lib/Target/AArch64/AArch64TargetTransformInfo.cpp

Modified: llvm/trunk/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AArch64/AArch64TargetTransformInfo.cpp?rev=216141&r1=216140&r2=216141&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AArch64/AArch64TargetTransformInfo.cpp (original)
+++ llvm/trunk/lib/Target/AArch64/AArch64TargetTransformInfo.cpp Wed Aug 20 19:02:51 2014
@@ -104,7 +104,7 @@ public:
     return 64;
   }
 
-  unsigned getMaximumUnrollFactor() const override { return 2; }
+  unsigned getMaximumUnrollFactor() const override;
 
   unsigned getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src) const
       override;
@@ -513,3 +513,9 @@ unsigned AArch64TTI::getCostOfKeepingLiv
   }
   return Cost;
 }
+
+unsigned AArch64TTI::getMaximumUnrollFactor() const {
+  if (ST->isCortexA57() || ST->isCyclone())
+    return 4;
+  return 2;
+}