shithub: asif

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add bitwise round up to next power of 2

--- a/asif.h

+++ b/asif.h

@@ -16,6 +16,7 @@

 void	vinsert(VArray*, char*);

 VArray*	valloc(ulong, int);

+u32int	next32pow2(u32int);

 int	lsb64(uvlong);

 int	msb64(uvlong);

--- a/bit.c

+++ b/bit.c

@@ -2,6 +2,19 @@

 #include <libc.h>

 #include "asif.h"

+/* 32bit round up to next power of 2 */

+u32int

+next32pow2(u32int v)

+{

+	v--;

+	v |= v >> 1;

+	v |= v >> 2;

+	v |= v >> 4;

+	v |= v >> 8;

+	v |= v >> 16;

+	return v + 1;

+}

+

 /* find least significant set bit in 64bit integers */

 int

 lsb64(uvlong v)