813b8a9e89
Newer versions of GCC include an __ffssi2() symbol in libgcc and the compiler can emit calls to it in generated code. This is true for at least GCC 6.2 when compiling world for mips and mips64. Reviewed by: jmallett, dim Sponsored by: DARPA / AFRL Differential Revision: https://reviews.freebsd.org/D10086
30 lines
793 B
C
30 lines
793 B
C
/* ===-- ffssi2.c - Implement __ffssi2 -------------------------------------===
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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 __ffssi2 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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/* 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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__ffssi2(si_int a)
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{
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if (a == 0)
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{
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return 0;
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}
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return __builtin_ctz(a) + 1;
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}
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