1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * ashrdi3.c extracted from gcc-2.7.2/libgcc2.c which is:
4  * Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
5  */
6 
7 #define BITS_PER_UNIT 8
8 
9 typedef		 int SItype	__attribute__((mode(SI)));
10 typedef unsigned int USItype	__attribute__((mode(SI)));
11 typedef		 int DItype	__attribute__((mode(DI)));
12 typedef int word_type           __attribute__((mode(__word__)));
13 
14 struct DIstruct {
15 	SItype high, low;
16 };
17 
18 typedef union {
19 	struct DIstruct s;
20 	DItype ll;
21 } di_union;
22 
__ashrdi3(DItype u,word_type b)23 DItype __ashrdi3(DItype u, word_type b)
24 {
25 	di_union w;
26 	word_type bm;
27 	di_union uu;
28 
29 	if (b == 0)
30 		return u;
31 
32 	uu.ll = u;
33 
34 	bm = (sizeof(SItype) * BITS_PER_UNIT) - b;
35 	if (bm <= 0) {
36 		/* w.s.high = 1..1 or 0..0 */
37 		w.s.high = uu.s.high >> (sizeof(SItype) * BITS_PER_UNIT - 1);
38 		w.s.low = uu.s.high >> -bm;
39 	} else {
40 		USItype carries = (USItype)uu.s.high << bm;
41 
42 		w.s.high = uu.s.high >> b;
43 		w.s.low = ((USItype)uu.s.low >> b) | carries;
44 	}
45 
46 	return w.ll;
47 }
48 
49