patch-2.1.106 linux/include/asm-i386/bitops.h
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- Lines: 34
- Date:
Sat Jun 13 12:56:46 1998
- Orig file:
v2.1.105/linux/include/asm-i386/bitops.h
- Orig date:
Mon Dec 1 11:16:57 1997
diff -u --recursive --new-file v2.1.105/linux/include/asm-i386/bitops.h linux/include/asm-i386/bitops.h
@@ -187,6 +187,33 @@
return word;
}
+/*
+ * ffs: find first bit set. This is defined the same way as
+ * the libc and compiler builtin ffs routines, therefore
+ * differs in spirit from the above ffz (man ffs).
+ */
+
+extern __inline__ int ffs(int x)
+{
+ int r;
+
+ __asm__("bsfl %1,%0\n\t"
+ "jnz 1f\n\t"
+ "movl $-1,%0\n"
+ "1:" : "=r" (r) : "g" (x));
+ return r+1;
+}
+
+/*
+ * hweightN: returns the hamming weight (i.e. the number
+ * of bits set) of a N-bit word
+ */
+
+#define hweight32(x) generic_hweight32(x)
+#define hweight16(x) generic_hweight16(x)
+#define hweight8(x) generic_hweight8(x)
+
+
#ifdef __KERNEL__
#define ext2_set_bit test_and_set_bit
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