diff libiberty/ffs.c @ 0:a06113de4d67

first commit
author kent <kent@cr.ie.u-ryukyu.ac.jp>
date Fri, 17 Jul 2009 14:47:48 +0900
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libiberty/ffs.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,26 @@
+/* ffs -- Find the first bit set in the parameter
+
+@deftypefn Supplemental int ffs (int @var{valu})
+
+Find the first (least significant) bit set in @var{valu}.  Bits are
+numbered from right to left, starting with bit 1 (corresponding to the
+value 1).  If @var{valu} is zero, zero is returned.
+
+@end deftypefn
+
+*/
+
+int
+ffs (register int valu)
+{
+  register int bit;
+
+  if (valu == 0)
+    return 0;
+
+  for (bit = 1; !(valu & 1); bit++)
+  	valu >>= 1;
+
+  return bit;
+}
+