Revert "[CodeGenPrepare] Move sign/zero extensions near loads using type promotion."

This reverts commit r224351. It causes assertion failures when building
ICU.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224397 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Target/TargetLowering.h

@@ -264,11 +264,6 @@ public:
     return MaskAndBranchFoldingIsLegal;
   }
 
-  /// \brief Return true if the target wants to use the optimization that
-  /// turns ext(promotableInst1(...(promotableInstN(load)))) into
-  /// promotedInst1(...(promotedInstN(ext(load)))).
-  bool enableExtLdPromotion() const { return EnableExtLdPromotion; }
-
   /// Return true if the target can combine store(extractelement VectorTy,
   /// Idx).
   /// \p Cost[out] gives the cost of that transformation when this is true.
@@ -1959,9 +1954,6 @@ protected:
   /// a mask of a single bit, a compare, and a branch into a single instruction.
   bool MaskAndBranchFoldingIsLegal;
 
-  /// \see enableExtLdPromotion.
-  bool EnableExtLdPromotion;
-
 protected:
   /// Return true if the value types that can be represented by the specified
   /// register class are all legal.