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authorSamuel Thibault <samuel.thibault@ens-lyon.org>2013-07-27 22:15:10 +0000
committerSamuel Thibault <samuel.thibault@ens-lyon.org>2013-07-27 22:15:10 +0000
commitb5875be0451b92bdd99663c8305ae46bd6a7d90c (patch)
tree68a6a5f79ac618c79ba3777c21faaea9aec2f0b4 /libdde-linux26/contrib/include/asm-generic/bitops/fls.h
parentce6a36c7f7c88e7ca0fda816f9282237bb86829d (diff)
parent7996a3d79d55b7f879dfd62e202bbfe2963718d3 (diff)
Merge branch 'upstream-merged'
Diffstat (limited to 'libdde-linux26/contrib/include/asm-generic/bitops/fls.h')
-rw-r--r--libdde-linux26/contrib/include/asm-generic/bitops/fls.h41
1 files changed, 41 insertions, 0 deletions
diff --git a/libdde-linux26/contrib/include/asm-generic/bitops/fls.h b/libdde-linux26/contrib/include/asm-generic/bitops/fls.h
new file mode 100644
index 00000000..0576d1f4
--- /dev/null
+++ b/libdde-linux26/contrib/include/asm-generic/bitops/fls.h
@@ -0,0 +1,41 @@
+#ifndef _ASM_GENERIC_BITOPS_FLS_H_
+#define _ASM_GENERIC_BITOPS_FLS_H_
+
+/**
+ * fls - find last (most-significant) bit set
+ * @x: the word to search
+ *
+ * This is defined the same way as ffs.
+ * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
+ */
+
+static __always_inline int 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;
+}
+
+#endif /* _ASM_GENERIC_BITOPS_FLS_H_ */