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/* ===-- fixunsxfti.c - Implement __fixunsxfti -----------------------------=== 
 * 
 *      	       The LLVM Compiler Infrastructure 
 * 
 * This file is dual licensed under the MIT and the University of Illinois Open 
 * Source Licenses. See LICENSE.TXT for details. 
 * 
 * ===----------------------------------------------------------------------=== 
 * 
 * This file implements __fixunsxfti for the compiler_rt library. 
 * 
 * ===----------------------------------------------------------------------=== 
 */ 
 
#include "int_lib.h" 
 
#ifdef CRT_HAS_128BIT 
 
/* Returns: convert a to a unsigned long long, rounding toward zero. 
 *          Negative values all become zero. 
 */ 
 
/* Assumption: long double is an intel 80 bit floating point type padded with 6 bytes 
 *             tu_int is a 128 bit integral type 
 *             value in long double is representable in tu_int or is negative  
 */ 
 
/* gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee eeee | 
 * 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm 
 */ 
 
COMPILER_RT_ABI tu_int 
__fixunsxfti(long double a) 
{ 
    long_double_bits fb; 
    fb.f = a; 
    int e = (fb.u.high.s.low & 0x00007FFF) - 16383; 
    if (e < 0 || (fb.u.high.s.low & 0x00008000)) 
        return 0; 
    if ((unsigned)e > sizeof(tu_int) * CHAR_BIT) 
        return ~(tu_int)0; 
    tu_int r = fb.u.low.all; 
    if (e > 63) 
        r <<= (e - 63); 
    else 
        r >>= (63 - e); 
    return r; 
} 
 
#endif /* CRT_HAS_128BIT */