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Some architectures need __c[lt]z[sd]i2() for __builtin_c[lt]z[ll] and that causes a build failure. They can be implemented using the fls()/__ffs() and overridden by linking arch-specific versions may not be implemented yet. This is required by "lib: add lz4 compressor module". Reference: https://lkml.org/lkml/2013/4/18/603 Signed-off-by: Chanho Min <chanho.min@lge.com> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: "Darrick J. Wong" <djwong@us.ibm.com> Cc: Bob Pearson <rpearson@systemfabricworks.com> Cc: Richard Weinberger <richard@nod.at> Cc: Herbert Xu <herbert@gondor.hengli.com.au> Cc: Yann Collet <yann.collet.73@gmail.com> Cc: Kyungsik Lee <kyungsik.lee@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
58 lines
1,009 B
C
58 lines
1,009 B
C
/*
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* lib/clz_ctz.c
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*
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* Copyright (C) 2013 Chanho Min <chanho.min@lge.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* __c[lt]z[sd]i2 can be overridden by linking arch-specific versions.
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*/
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#include <linux/export.h>
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#include <linux/kernel.h>
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int __weak __ctzsi2(int val)
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{
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return __ffs(val);
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}
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EXPORT_SYMBOL(__ctzsi2);
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int __weak __clzsi2(int val)
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{
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return 32 - fls(val);
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}
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EXPORT_SYMBOL(__clzsi2);
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#if BITS_PER_LONG == 32
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int __weak __clzdi2(long val)
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{
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return 32 - fls((int)val);
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}
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EXPORT_SYMBOL(__clzdi2);
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int __weak __ctzdi2(long val)
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{
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return __ffs((u32)val);
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}
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EXPORT_SYMBOL(__ctzdi2);
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#elif BITS_PER_LONG == 64
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int __weak __clzdi2(long val)
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{
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return 64 - fls64((u64)val);
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}
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EXPORT_SYMBOL(__clzdi2);
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int __weak __ctzdi2(long val)
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{
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return __ffs64((u64)val);
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}
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EXPORT_SYMBOL(__ctzdi2);
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#else
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#error BITS_PER_LONG not 32 or 64
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#endif
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