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Diffstat (limited to 'include/asm-generic/bitops/builtin-__fls.h')
-rw-r--r--include/asm-generic/bitops/builtin-__fls.h15
1 files changed, 15 insertions, 0 deletions
diff --git a/include/asm-generic/bitops/builtin-__fls.h b/include/asm-generic/bitops/builtin-__fls.h
new file mode 100644
index 00000000000..0248f386635
--- /dev/null
+++ b/include/asm-generic/bitops/builtin-__fls.h
@@ -0,0 +1,15 @@
+#ifndef _ASM_GENERIC_BITOPS_BUILTIN___FLS_H_
+#define _ASM_GENERIC_BITOPS_BUILTIN___FLS_H_
+
+/**
+ * __fls - find last (most-significant) set bit in a long word
+ * @word: the word to search
+ *
+ * Undefined if no set bit exists, so code should check against 0 first.
+ */
+static __always_inline unsigned long __fls(unsigned long word)
+{
+ return (sizeof(word) * 8) - 1 - __builtin_clzl(word);
+}
+
+#endif