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//===-- lshrti3.c - Implement __lshrti3 -----------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __lshrti3 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#if __x86_64
#include "int_lib.h"
// Returns: logical a >> b
// Precondition: 0 <= b < bits_in_tword
ti_int
__lshrti3(ti_int a, si_int b)
{
const int bits_in_dword = (int)(sizeof(di_int) * CHAR_BIT);
utwords input;
utwords result;
input.all = a;
if (b & bits_in_dword) // bits_in_dword <= b < bits_in_tword
{
result.high = 0;
result.low = input.high >> (b - bits_in_dword);
}
else // 0 <= b < bits_in_dword
{
if (b == 0)
return a;
result.high = input.high >> b;
result.low = (input.high << (bits_in_dword - b)) | (input.low >> b);
}
return result.all;
}
#endif
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