Bit Manipulation Functions

There are three new functions in this class plus the new intrinsic ILEN:

• LEADZ -- number of leading zeros
• POPCNT -- number of 1 bits
• POPPAR -- parity of integer

All functions are elemental but must take INTEGER arguments and report on the bit patterns of INTEGER variables. The Fortran 90 Standard (Section 13.5.7) explains how integers are interpreted. Consider the artificial binary number I = 00001011,

• LEADZ(I) is 4
• POPCNT(I) is 3
• POPPAR(I) is 1 (the alternative is 0)

The result is always of the same kind as the argument.