29 lines
791 B
C
29 lines
791 B
C
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//===-- ctzdi2.c - Implement __ctzdi2 -------------------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements __ctzdi2 for the compiler_rt library.
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//
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//===----------------------------------------------------------------------===//
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#include "int_lib.h"
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// Returns: the number of trailing 0-bits
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// Precondition: a != 0
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si_int
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__ctzdi2(di_int a)
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{
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dwords x;
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x.all = a;
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const si_int f = -(x.low == 0);
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return __builtin_ctz((x.high & f) | (x.low & ~f)) +
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(f & ((si_int)(sizeof(si_int) * CHAR_BIT)));
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}
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