[Commit] libic/src iccolor.c,1.2,1.3

[Richard Henderson]

Committed by: rth

Update of /local/src/CVS/libic/src
In directory home.keithp.com:/tmp/cvs-serv4135/src

Modified Files:
	iccolor.c 
Log Message:
	* src/iccolor.c (Ones): Define as __builtin_popcount when available.


Index: iccolor.c
===================================================================
RCS file: /local/src/CVS/libic/src/iccolor.c,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -d -r1.2 -r1.3
--- iccolor.c	31 Jul 2003 17:00:09 -0000	1.2
+++ iccolor.c	1 Aug 2003 03:46:21 -0000	1.3
@@ -25,11 +25,20 @@
 
 #include "icint.h"
 
+/* GCC 3.4 supports a "population count" builtin, which on many targets is
+   implemented with a single instruction.  There is a fallback definition
+   in libgcc in case a target does not have one, which should be just as
+   good as the static function below.  */
+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
+# if __INT_MIN__ == 0x7fffffff
+#  define Ones(mask)		__builtin_popcount(mask)
+# else
+#  define Ones(mask)		__builtin_popcountl((mask) & 0xffffffff)
+# endif
+#else
+/* Otherwise fall back on HACKMEM 169.  */
 static int
-Ones(unsigned long mask);
-
-static int
-Ones(unsigned long mask)                /* HACKMEM 169 */
+Ones(unsigned long mask)
 {
     register unsigned long y;
 
@@ -37,6 +46,7 @@
     y = mask - y - ((y >>1) & 033333333333);
     return (((y + (y >> 3)) & 030707070707) % 077);
 }
+#endif
 
 void
 IcColorToPixel (const IcFormat	*format,