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/* ===-- clzti2.c - Implement __clzti2 -------------------------------------=== |
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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 __clzti2 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 number of leading 0-bits */ |
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/* Precondition: a != 0 */ |
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COMPILER_RT_ABI si_int |
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__clzti2(ti_int a) |
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{ |
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twords x; |
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x.all = a; |
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const di_int f = -(x.s.high == 0); |
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return __builtin_clzll((x.s.high & ~f) | (x.s.low & f)) + |
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((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT))); |
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} |
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#endif /* CRT_HAS_128BIT */ |