TargetTransformInfo: address calculation parameter for gather/scather

Address calculation for gather/scather in vectorized code can incur a
significant cost making vectorization unbeneficial. Add infrastructure to add
cost.
Tests and cost model for targets will be in follow-up commits.

radar://14351991

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186187 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 1 deletions

diff --git a/include/llvm/Analysis/TargetTransformInfo.h b/include/llvm/Analysis/TargetTransformInfo.h
index eb29e34..b8a44b5 100644
--- a/include/llvm/Analysis/TargetTransformInfo.h
+++ b/include/llvm/Analysis/TargetTransformInfo.h
@@ -339,7 +339,11 @@ public:
   /// merged into the instruction indexing mode. Some targets might want to
   /// distinguish between address computation for memory operations on vector
   /// types and scalar types. Such targets should override this function.
-  virtual unsigned getAddressComputationCost(Type *Ty) const;
+  /// The 'IsComplex' parameter is a hint that the address computation is likely
+  /// to involve multiple instructions and as such unlikely to be merged into
+  /// the address indexing mode.
+  virtual unsigned getAddressComputationCost(Type *Ty,
+                                             bool IsComplex = false) const;
 
   /// @}