GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libcompiler_rt/popcountsi2.c Lines: 0 5 0.0 %
Date: 2017-11-13 Branches: 0 0 0.0 %

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/* ===-- popcountsi2.c - Implement __popcountsi2 ---------------------------===
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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 __popcountsi2 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: count of 1 bits */
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COMPILER_RT_ABI si_int
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__popcountsi2(si_int a)
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{
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    su_int x = (su_int)a;
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    x = x - ((x >> 1) & 0x55555555);
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    /* Every 2 bits holds the sum of every pair of bits */
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    x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
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    /* Every 4 bits holds the sum of every 4-set of bits (3 significant bits) */
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    x = (x + (x >> 4)) & 0x0F0F0F0F;
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    /* Every 8 bits holds the sum of every 8-set of bits (4 significant bits) */
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    x = (x + (x >> 16));
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    /* The lower 16 bits hold two 8 bit sums (5 significant bits).*/
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    /*    Upper 16 bits are garbage */
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    return (x + (x >> 8)) & 0x0000003F;  /* (6 significant bits) */
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}