strings.h File Reference

Go to the source code of this file.

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
static	__attribute__ ((always_inline)) int __ffsl(long value)
	Find first (i.e.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

__attribute__()

__attribute__ ( (always_inline) )

inlinestatic

Find first (i.e.

Find last (i.e.

least significant) set bit

Parameters

value

Value

Return values

lsb	Least significant bit set in value (LSB=1), or zero

most significant) set bit

Parameters

value

Value

Return values

msb	Most significant bit set in value (LSB=1), or zero

Definition at line 12 of file strings.h.

                                                                          {
        long lsb_minus_one;
 
        /* If the input value is zero, the BSF instruction returns
         * ZF=0 and leaves an undefined value in the output register.
         * Perform this check in C rather than asm so that it can be
         * omitted in cases where the compiler is able to prove that
         * the input is non-zero.
         */
        if ( value ) {
                __asm__ ( "bsfl %1, %0"
                          : "=r" ( lsb_minus_one )
                          : "rm" ( value ) );
                return ( lsb_minus_one + 1 );
        } else {
                return 0;
        }
}

References __asm__(), and value.