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/* ===-- ffsti2.c - Implement __ffsti2 -------------------------------------=== |
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* |
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* The LLVM Compiler Infrastructure |
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* |
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* This file is dual licensed under the MIT and the University of Illinois Open |
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* Source Licenses. See LICENSE.TXT for details. |
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* |
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* ===----------------------------------------------------------------------=== |
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* |
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* This file implements __ffsti2 for the compiler_rt library. |
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* |
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* ===----------------------------------------------------------------------=== |
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*/ |
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#include "int_lib.h" |
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#ifdef CRT_HAS_128BIT |
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/* Returns: the index of the least significant 1-bit in a, or |
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* the value zero if a is zero. The least significant bit is index one. |
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*/ |
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COMPILER_RT_ABI si_int |
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__ffsti2(ti_int a) |
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{ |
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twords x; |
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x.all = a; |
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if (x.s.low == 0) |
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{ |
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if (x.s.high == 0) |
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return 0; |
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return __builtin_ctzll(x.s.high) + (1 + sizeof(di_int) * CHAR_BIT); |
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} |
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return __builtin_ctzll(x.s.low) + 1; |
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} |
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#endif /* CRT_HAS_128BIT */ |