IBM Extension

LEADZ(I)

Purpose

Returns the number of leading zero-bits in the binary representation of an integer.

Class

Elemental function

Argument type and attributes

I
must be of type integer.

Result type and attributes

Same as I.

Result value

The result is the count of zero-bits to the left of the leftmost one-bit for an integer.

Examples

 I = LEADZ(0_4)  ! I=32
 J = LEADZ(4_4)  ! J=29
 K = LEADZ(-1_4) ! K=0
End of IBM Extension