X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Flinux%2Fbitops.h;h=5d1eabcde5d5f273e6b3e9450c23e0861f69c84c;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=cb3c3ef50f504408c242028ef3b2e9f1feb7347a;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git

diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index cb3c3ef50..5d1eabcde 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -2,74 +2,6 @@
 #define _LINUX_BITOPS_H
 #include <asm/types.h>
 
-/*
- * 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).
- */
-
-static inline int generic_ffs(int x)
-{
-	int r = 1;
-
-	if (!x)
-		return 0;
-	if (!(x & 0xffff)) {
-		x >>= 16;
-		r += 16;
-	}
-	if (!(x & 0xff)) {
-		x >>= 8;
-		r += 8;
-	}
-	if (!(x & 0xf)) {
-		x >>= 4;
-		r += 4;
-	}
-	if (!(x & 3)) {
-		x >>= 2;
-		r += 2;
-	}
-	if (!(x & 1)) {
-		x >>= 1;
-		r += 1;
-	}
-	return r;
-}
-
-/*
- * fls: find last bit set.
- */
-
-static __inline__ int generic_fls(int x)
-{
-	int r = 32;
-
-	if (!x)
-		return 0;
-	if (!(x & 0xffff0000u)) {
-		x <<= 16;
-		r -= 16;
-	}
-	if (!(x & 0xff000000u)) {
-		x <<= 8;
-		r -= 8;
-	}
-	if (!(x & 0xf0000000u)) {
-		x <<= 4;
-		r -= 4;
-	}
-	if (!(x & 0xc0000000u)) {
-		x <<= 2;
-		r -= 2;
-	}
-	if (!(x & 0x80000000u)) {
-		x <<= 1;
-		r -= 1;
-	}
-	return r;
-}
-
 /*
  * Include this here because some architectures need generic_ffs/fls in
  * scope
@@ -84,54 +16,19 @@ static __inline__ int get_bitmask_order(unsigned int count)
 	return order;	/* We could be slightly more clever with -1 here... */
 }
 
-/*
- * hweightN: returns the hamming weight (i.e. the number
- * of bits set) of a N-bit word
- */
-
-static inline unsigned int generic_hweight32(unsigned int w)
-{
-        unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
-        res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
-        res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
-        res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
-        return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
-}
-
-static inline unsigned int generic_hweight16(unsigned int w)
-{
-        unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555);
-        res = (res & 0x3333) + ((res >> 2) & 0x3333);
-        res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F);
-        return (res & 0x00FF) + ((res >> 8) & 0x00FF);
-}
-
-static inline unsigned int generic_hweight8(unsigned int w)
-{
-        unsigned int res = (w & 0x55) + ((w >> 1) & 0x55);
-        res = (res & 0x33) + ((res >> 2) & 0x33);
-        return (res & 0x0F) + ((res >> 4) & 0x0F);
-}
-
-static inline unsigned long generic_hweight64(__u64 w)
+static __inline__ int get_count_order(unsigned int count)
 {
-#if BITS_PER_LONG < 64
-	return generic_hweight32((unsigned int)(w >> 32)) +
-				generic_hweight32((unsigned int)w);
-#else
-	u64 res;
-	res = (w & 0x5555555555555555ul) + ((w >> 1) & 0x5555555555555555ul);
-	res = (res & 0x3333333333333333ul) + ((res >> 2) & 0x3333333333333333ul);
-	res = (res & 0x0F0F0F0F0F0F0F0Ful) + ((res >> 4) & 0x0F0F0F0F0F0F0F0Ful);
-	res = (res & 0x00FF00FF00FF00FFul) + ((res >> 8) & 0x00FF00FF00FF00FFul);
-	res = (res & 0x0000FFFF0000FFFFul) + ((res >> 16) & 0x0000FFFF0000FFFFul);
-	return (res & 0x00000000FFFFFFFFul) + ((res >> 32) & 0x00000000FFFFFFFFul);
-#endif
+	int order;
+	
+	order = fls(count) - 1;
+	if (count & (count - 1))
+		order++;
+	return order;
 }
 
 static inline unsigned long hweight_long(unsigned long w)
 {
-	return sizeof(w) == 4 ? generic_hweight32(w) : generic_hweight64(w);
+	return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
 }
 
 /*
@@ -156,4 +53,11 @@ static inline __u32 ror32(__u32 word, unsigned int shift)
 	return (word >> shift) | (word << (32 - shift));
 }
 
+static inline unsigned fls_long(unsigned long l)
+{
+	if (sizeof(l) == 4)
+		return fls(l);
+	return fls64(l);
+}
+
 #endif