Move BitCount() macro from hamt.c to util.h.

svn path=/trunk/yasm/; revision=488

1 files changed, 13 insertions, 0 deletions

diff --git a/util.h b/util.h
index abd7f539..2dbd480f 100644
--- a/util.h
+++ b/util.h
@@ -135,6 +135,19 @@ int strncasecmp(const char *s1, const char *s2, size_t n);
 void xfree(/*@only@*/ /*@out@*/ /*@null@*/ void *p);
 #endif
 
+/* Bit-counting: used primarily by HAMT but also in a few other places. */
+#define SK5	0x55555555
+#define SK3	0x33333333
+#define SKF0	0x0F0F0F0F
+#define BitCount(d, s)		do {		\
+	d = s;					\
+	d -= (d>>1) & SK5;			\
+	d = (d & SK3) + ((d>>2) & SK3);		\
+	d = (d & SKF0) + ((d>>4) & SKF0);	\
+	d += d>>16;				\
+	d += d>>8;				\
+    } while (0)
+
 #include "coretype.h"
 
 #include "valparam.h"