41 lines
1.1 KiB
C
41 lines
1.1 KiB
C
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/* clang-format off */
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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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STATIC_YOINK("huge_compiler_rt_license");
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#include "third_party/compiler_rt/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 */
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