xref: /openbmc/u-boot/arch/arc/lib/libgcc2.c (revision f739fcd8)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 1989-2013 Free Software Foundation, Inc.
4  */
5 
6 #include "libgcc2.h"
7 
8 DWtype
9 __ashldi3(DWtype u, shift_count_type b)
10 {
11 	if (b == 0)
12 		return u;
13 
14 	const DWunion uu = {.ll = u};
15 	const shift_count_type bm = W_TYPE_SIZE - b;
16 	DWunion w;
17 
18 	if (bm <= 0) {
19 		w.s.low = 0;
20 		w.s.high = (UWtype)uu.s.low << -bm;
21 	} else {
22 		const UWtype carries = (UWtype) uu.s.low >> bm;
23 
24 		w.s.low = (UWtype)uu.s.low << b;
25 		w.s.high = ((UWtype)uu.s.high << b) | carries;
26 	}
27 
28 	return w.ll;
29 }
30 
31 DWtype
32 __ashrdi3(DWtype u, shift_count_type b)
33 {
34 	if (b == 0)
35 		return u;
36 
37 	const DWunion uu = {.ll = u};
38 	const shift_count_type bm = W_TYPE_SIZE - b;
39 	DWunion w;
40 
41 	if (bm <= 0) {
42 		/* w.s.high = 1..1 or 0..0 */
43 		w.s.high = uu.s.high >> (W_TYPE_SIZE - 1);
44 		w.s.low = uu.s.high >> -bm;
45 	} else {
46 		const UWtype carries = (UWtype) uu.s.high << bm;
47 
48 		w.s.high = uu.s.high >> b;
49 		w.s.low = ((UWtype)uu.s.low >> b) | carries;
50 	}
51 
52 	return w.ll;
53 }
54 
55 DWtype
56 __lshrdi3(DWtype u, shift_count_type b)
57 {
58 	if (b == 0)
59 		return u;
60 
61 	const DWunion uu = {.ll = u};
62 	const shift_count_type bm = W_TYPE_SIZE - b;
63 	DWunion w;
64 
65 	if (bm <= 0) {
66 		w.s.high = 0;
67 		w.s.low = (UWtype)uu.s.high >> -bm;
68 	} else {
69 		const UWtype carries = (UWtype)uu.s.high << bm;
70 
71 		w.s.high = (UWtype)uu.s.high >> b;
72 		w.s.low = ((UWtype)uu.s.low >> b) | carries;
73 	}
74 
75 	return w.ll;
76 }
77 
78 unsigned long
79 udivmodsi4(unsigned long num, unsigned long den, int modwanted)
80 {
81 	unsigned long bit = 1;
82 	unsigned long res = 0;
83 
84 	while (den < num && bit && !(den & (1L<<31))) {
85 		den <<= 1;
86 		bit <<= 1;
87 	}
88 
89 	while (bit) {
90 		if (num >= den) {
91 			num -= den;
92 			res |= bit;
93 		}
94 		bit >>= 1;
95 		den >>= 1;
96 	}
97 
98 	if (modwanted)
99 		return num;
100 
101 	return res;
102 }
103 
104 long
105 __divsi3(long a, long b)
106 {
107 	int neg = 0;
108 	long res;
109 
110 	if (a < 0) {
111 		a = -a;
112 		neg = !neg;
113 	}
114 
115 	if (b < 0) {
116 		b = -b;
117 		neg = !neg;
118 	}
119 
120 	res = udivmodsi4(a, b, 0);
121 
122 	if (neg)
123 		res = -res;
124 
125 	return res;
126 }
127 
128 long
129 __modsi3(long a, long b)
130 {
131 	int neg = 0;
132 	long res;
133 
134 	if (a < 0) {
135 		a = -a;
136 		neg = 1;
137 	}
138 
139 	if (b < 0)
140 		b = -b;
141 
142 	res = udivmodsi4(a, b, 1);
143 
144 	if (neg)
145 		res = -res;
146 
147 	return res;
148 }
149 
150 long
151 __udivsi3(long a, long b)
152 {
153 	return udivmodsi4(a, b, 0);
154 }
155 
156 long
157 __umodsi3(long a, long b)
158 {
159 	return udivmodsi4(a, b, 1);
160 }
161