インテル® Fortran コンパイラー XE 13.1 ユーザー・リファレンス・ガイド
Elemental Intrinsic Function (Generic): Returns the number of 1 bits in the integer argument.
The result type and kind is the same as i. The result value is the number of 1 bits in the binary representation of the integer i.
The model for the interpretation of an integer value as a sequence of bits is shown in Model for Bit Data.