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/* ===-- lshrdi3.c - Implement __lshrdi3 -----------------------------------=== 
 * 
 *                     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 __lshrdi3 for the compiler_rt library. 
 * 
 * ===----------------------------------------------------------------------=== 
 */ 
 
#include "int_lib.h" 
 
/* Returns: logical a >> b */ 
 
/* Precondition:  0 <= b < bits_in_dword */ 
 
ARM_EABI_FNALIAS(llsr, lshrdi3) 
 
COMPILER_RT_ABI di_int 
__lshrdi3(di_int a, si_int b) 
{ 
    const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT); 
    udwords input; 
    udwords result; 
    input.all = a; 
    if (b & bits_in_word)  /* bits_in_word <= b < bits_in_dword */ 
    { 
        result.s.high = 0; 
        result.s.low = input.s.high >> (b - bits_in_word); 
    } 
    else  /* 0 <= b < bits_in_word */ 
    { 
        if (b == 0) 
            return a; 
        result.s.high  = input.s.high >> b; 
        result.s.low = (input.s.high << (bits_in_word - b)) | (input.s.low >> b); 
    } 
    return result.all; 
}