1 /* ===-- lshrdi3.c - Implement __lshrdi3 -----------------------------------===
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 __lshrdi3 for the compiler_rt library.
12 * ===----------------------------------------------------------------------===
17 /* Returns: logical a >> b */
19 /* Precondition: 0 <= b < bits_in_dword */
21 ARM_EABI_FNALIAS(llsr
, lshrdi3
)
23 COMPILER_RT_ABI di_int
24 __lshrdi3(di_int a
, si_int b
)
26 const int bits_in_word
= (int)(sizeof(si_int
) * CHAR_BIT
);
30 if (b
& bits_in_word
) /* bits_in_word <= b < bits_in_dword */
33 result
.s
.low
= input
.s
.high
>> (b
- bits_in_word
);
35 else /* 0 <= b < bits_in_word */
39 result
.s
.high
= input
.s
.high
>> b
;
40 result
.s
.low
= (input
.s
.high
<< (bits_in_word
- b
)) | (input
.s
.low
>> b
);