ggidev-invert_3

Section: GGI (3)
Updated: 2006-12-30
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NAME

ggidev-invert_3, ggidev-lshift_3, ggidev-rshift_3 : Bitwise triple-int operations

SYNOPSIS

#include <ggi/internal/triple-int.h>

unsigned *invert_3(unsigned x[3]);

unsigned *lshift_3(unsigned l[3], unsigned r);
unsigned *rshift_3(unsigned l[3], unsigned r);

DESCRIPTION

invert_3 inverts all bits of x. Equivalent to x=~x.

lshift_3 shifts l to the left by r bits. Equivalent to l<<=r.

rshift_3 shifts l to the right by r bits. This shift is arithmetic, so the sign of l is kept as is. Equivalent to l>>=r.

RETURN VALUE

invert_3 returns a pointer to x which has been updated in place.

Both lshift_3 and rshift_3 return a pointer to l which has been updated in place.

EXAMPLES

Some bitwise operations on triple-ints:

unsigned x[3];

assign_int_3(x, -4);
invert_3(x);     /* x is now 3 */
lshift_3(x, 42); /* x is now 3*2^42, if that fits in a triple-int */
rshift_3(x, 17); /* x is now 3*2^25 */