[APInt] Remove the And/Or/Xor/Not functions from the APIntOps namespace.

[craig.topper]

Summary

They aren't used anywhere in tree and its preferable to use the &, |, ^, or ~ operators.

With my patch to add rvalue reference support to &, |, ^ operators it also becomes less performant to use these functions.

[RKSimon]

LGTM

include/llvm/ADT/APInt.h

 /// Performs addition on APInt values.
 inline APInt add(const APInt &LHS, const APInt &RHS) { return LHS + RHS; }
 
 /// \brief Function for subtraction operation.
 ///
 /// Performs subtraction on APInt values.
 inline APInt sub(const APInt &LHS, const APInt &RHS) { return LHS - RHS; }
 
-/// \brief Bitwise AND function for APInt.
-///
-/// Performs bitwise AND operation on APInt LHS and
-/// APInt RHS.
-inline APInt And(const APInt &LHS, const APInt &RHS) { return LHS & RHS; }
-
-/// \brief Bitwise OR function for APInt.
-///
-/// Performs bitwise OR operation on APInt LHS and APInt RHS.
-inline APInt Or(const APInt &LHS, const APInt &RHS) { return LHS | RHS; }
-
-/// \brief Bitwise XOR function for APInt.
-///
-/// Performs bitwise XOR operation on APInt.
-inline APInt Xor(const APInt &LHS, const APInt &RHS) { return LHS ^ RHS; }
-
-/// \brief Bitwise complement function.
-///
-/// Performs a bitwise complement operation on APInt.
-inline APInt Not(const APInt &APIVal) { return ~APIVal; }
-
 } // End of APIntOps namespace
 
 // See friend declaration above. This additional declaration is required in
 // order to compile LLVM with IBM xlC compiler.
 hash_code hash_value(const APInt &Arg);
 } // End of llvm namespace
 
 #endif