1 /*===-- ashrdi3.c - Implement __ashrdi3 -----------------------------------===
3 * The LLVM Compiler Infrastructure
5 * This file is dual licensed under the MIT and the University of Illinois Open
6 * Source Licenses. See LICENSE.TXT for details.
8 * ===----------------------------------------------------------------------===
10 * This file implements __ashrdi3 for the compiler_rt library.
12 * ===----------------------------------------------------------------------===
18 /* Returns: arithmetic a >> b */
20 /* Precondition: 0 <= b < bits_in_dword */
22 ARM_EABI_FNALIAS(lasr, ashrdi3);
24 COMPILER_RT_ABI di_int
25 __ashrdi3(di_int a, si_int b)
27 const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT);
31 if (b & bits_in_word) /* bits_in_word <= b < bits_in_dword */
33 /* result.s.high = input.s.high < 0 ? -1 : 0 */
34 result.s.high = input.s.high >> (bits_in_word - 1);
35 result.s.low = input.s.high >> (b - bits_in_word);
37 else /* 0 <= b < bits_in_word */
41 result.s.high = input.s.high >> b;
42 result.s.low = (input.s.high << (bits_in_word - b)) | (input.s.low >> b);