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| 3 | * lib/clz_ctz.c
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| 4 | *
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| 5 | * Copyright (C) 2013 Chanho Min <[email protected]>
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| 6 | *
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| 7 | * The functions in this file aren't called directly, but are required by
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| 8 | * GCC builtins such as __builtin_ctz, and therefore they can't be removed
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| 9 | * despite appearing unreferenced in kernel source.
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| 10 | *
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| 11 | * __c[lt]z[sd]i2 can be overridden by linking arch-specific versions.
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| 12 |
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| 13 |
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| 14 | #include <linux/export.h>
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| 15 | #include <linux/kernel.h>
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| 16 |
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| 17 | int __weak __ctzsi2(int val);
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| 18 | int __weak __attribute_const__ __ctzsi2(int val)
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| 19 | {
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| 20 | return __ffs(val);
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| 21 | }
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| 22 | EXPORT_SYMBOL(__ctzsi2);
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| 23 |
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| 24 | int __weak __clzsi2(int val);
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| 25 | int __weak __attribute_const__ __clzsi2(int val)
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| 26 | {
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| 27 | return 32 - fls(val);
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| 28 | }
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| 29 | EXPORT_SYMBOL(__clzsi2);
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| 30 |
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| 31 | int __weak __clzdi2(u64 val);
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| 32 | int __weak __attribute_const__ __clzdi2(u64 val)
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| 33 | {
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| 34 | return 64 - fls64(val);
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| 35 | }
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| 36 | EXPORT_SYMBOL(__clzdi2);
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| 37 |
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| 38 | int __weak __ctzdi2(u64 val);
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| 39 | int __weak __attribute_const__ __ctzdi2(u64 val)
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| 40 | {
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| 41 | return __ffs64(val);
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| 42 | }
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| 43 | EXPORT_SYMBOL(__ctzdi2);
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