Add getUnrollingPreferences to TTI

Allow targets to customize the default behavior of the generic loop unrolling
transformation. This will be used by the PowerPC backend when targeting the A2
core (which is in-order with a deep pipeline), and using more aggressive
defaults is important.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190542 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 3 insertions, 0 deletions

diff --git a/lib/CodeGen/BasicTargetTransformInfo.cpp b/lib/CodeGen/BasicTargetTransformInfo.cpp
index d5340e6..9c4b49a 100644
--- a/lib/CodeGen/BasicTargetTransformInfo.cpp
+++ b/lib/CodeGen/BasicTargetTransformInfo.cpp
@@ -84,6 +84,7 @@ public:
   virtual unsigned getJumpBufSize() const;
   virtual bool shouldBuildLookupTables() const;
   virtual bool haveFastSqrt(Type *Ty) const;
+  virtual void getUnrollingPreferences(Loop *L, UnrollingPreferences &UP) const;
 
   /// @}
 
@@ -189,6 +190,8 @@ bool BasicTTI::haveFastSqrt(Type *Ty) const {
   return TLI->isTypeLegal(VT) && TLI->isOperationLegalOrCustom(ISD::FSQRT, VT);
 }
 
+void BasicTTI::getUnrollingPreferences(Loop *, UnrollingPreferences &) const { }
+
 //===----------------------------------------------------------------------===//
 //
 // Calls used by the vectorizers.