[PATCH] arm: fix undefined reference to generic_fls

[powerpc.git] / include / asm-arm / bitops.h

diff --git a/include/asm-arm/bitops.h b/include/asm-arm/bitops.h
index d02de72..eaecd55 100644 (file)
--- a/include/asm-arm/bitops.h
+++ b/include/asm-arm/bitops.h
@@ -344,13 +344,42 @@ static inline unsigned long __ffs(unsigned long word)
 
 #else
 
+static inline int constant_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;
+}
+
 /*
  * On ARMv5 and above those functions can be implemented around
  * the clz instruction for much better code efficiency.
  */
 
 #define fls(x) \
-       ( __builtin_constant_p(x) ? generic_fls(x) : \
+       ( __builtin_constant_p(x) ? constant_fls(x) : \
          ({ int __r; asm("clz\t%0, %1" : "=r"(__r) : "r"(x) : "cc"); 32-__r; }) )
 #define fls64(x)   generic_fls64(x)
 #define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); })