048fa2df92
This patch implements ffs, __ffs, fls, __fls using __builtin_* gcc functions. These header files can be used by other architectures that rely on the gcc builtins. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
16 lines
397 B
C
16 lines
397 B
C
#ifndef _ASM_GENERIC_BITOPS_BUILTIN___FLS_H_
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#define _ASM_GENERIC_BITOPS_BUILTIN___FLS_H_
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/**
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* __fls - find last (most-significant) set bit in a long word
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* @word: the word to search
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*
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* Undefined if no set bit exists, so code should check against 0 first.
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*/
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static __always_inline unsigned long __fls(unsigned long word)
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{
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return (sizeof(word) * 8) - 1 - __builtin_clzl(word);
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}
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#endif
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