tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* longlong.h -- based on code from gcc-2.95.3
2
3 definitions for mixed size 32/64 bit arithmetic.
4 Copyright (C) 1991, 92, 94, 95, 96, 1997, 1998 Free Software Foundation, Inc.
5
6 This definition file is free software; you can redistribute it
7 and/or modify it under the terms of the GNU General Public
8 License as published by the Free Software Foundation; either
9 version 2, or (at your option) any later version.
10
11 This definition file is distributed in the hope that it will be
12 useful, but WITHOUT ANY WARRANTY; without even the implied
13 warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
14 See the GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
20
21/* Borrowed from GCC 2.95.3, I Molton 29/07/01 */
22
23#ifndef SI_TYPE_SIZE
24#define SI_TYPE_SIZE 32
25#endif
26
27#define __BITS4 (SI_TYPE_SIZE / 4)
28#define __ll_B (1L << (SI_TYPE_SIZE / 2))
29#define __ll_lowpart(t) ((USItype) (t) % __ll_B)
30#define __ll_highpart(t) ((USItype) (t) / __ll_B)
31
32/* Define auxiliary asm macros.
33
34 1) umul_ppmm(high_prod, low_prod, multipler, multiplicand)
35 multiplies two USItype integers MULTIPLER and MULTIPLICAND,
36 and generates a two-part USItype product in HIGH_PROD and
37 LOW_PROD.
38
39 2) __umulsidi3(a,b) multiplies two USItype integers A and B,
40 and returns a UDItype product. This is just a variant of umul_ppmm.
41
42 3) udiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
43 denominator) divides a two-word unsigned integer, composed by the
44 integers HIGH_NUMERATOR and LOW_NUMERATOR, by DENOMINATOR and
45 places the quotient in QUOTIENT and the remainder in REMAINDER.
46 HIGH_NUMERATOR must be less than DENOMINATOR for correct operation.
47 If, in addition, the most significant bit of DENOMINATOR must be 1,
48 then the pre-processor symbol UDIV_NEEDS_NORMALIZATION is defined to 1.
49
50 4) sdiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
51 denominator). Like udiv_qrnnd but the numbers are signed. The
52 quotient is rounded towards 0.
53
54 5) count_leading_zeros(count, x) counts the number of zero-bits from
55 the msb to the first non-zero bit. This is the number of steps X
56 needs to be shifted left to set the msb. Undefined for X == 0.
57
58 6) add_ssaaaa(high_sum, low_sum, high_addend_1, low_addend_1,
59 high_addend_2, low_addend_2) adds two two-word unsigned integers,
60 composed by HIGH_ADDEND_1 and LOW_ADDEND_1, and HIGH_ADDEND_2 and
61 LOW_ADDEND_2 respectively. The result is placed in HIGH_SUM and
62 LOW_SUM. Overflow (i.e. carry out) is not stored anywhere, and is
63 lost.
64
65 7) sub_ddmmss(high_difference, low_difference, high_minuend,
66 low_minuend, high_subtrahend, low_subtrahend) subtracts two
67 two-word unsigned integers, composed by HIGH_MINUEND_1 and
68 LOW_MINUEND_1, and HIGH_SUBTRAHEND_2 and LOW_SUBTRAHEND_2
69 respectively. The result is placed in HIGH_DIFFERENCE and
70 LOW_DIFFERENCE. Overflow (i.e. carry out) is not stored anywhere,
71 and is lost.
72
73 If any of these macros are left undefined for a particular CPU,
74 C macros are used. */
75
76#if defined (__arm__)
77#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
78 __asm__ ("adds %1, %4, %5 \n\
79 adc %0, %2, %3" \
80 : "=r" ((USItype) (sh)), \
81 "=&r" ((USItype) (sl)) \
82 : "%r" ((USItype) (ah)), \
83 "rI" ((USItype) (bh)), \
84 "%r" ((USItype) (al)), \
85 "rI" ((USItype) (bl)))
86#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
87 __asm__ ("subs %1, %4, %5 \n\
88 sbc %0, %2, %3" \
89 : "=r" ((USItype) (sh)), \
90 "=&r" ((USItype) (sl)) \
91 : "r" ((USItype) (ah)), \
92 "rI" ((USItype) (bh)), \
93 "r" ((USItype) (al)), \
94 "rI" ((USItype) (bl)))
95#define umul_ppmm(xh, xl, a, b) \
96{register USItype __t0, __t1, __t2; \
97 __asm__ ("%@ Inlined umul_ppmm \n\
98 mov %2, %5, lsr #16 \n\
99 mov %0, %6, lsr #16 \n\
100 bic %3, %5, %2, lsl #16 \n\
101 bic %4, %6, %0, lsl #16 \n\
102 mul %1, %3, %4 \n\
103 mul %4, %2, %4 \n\
104 mul %3, %0, %3 \n\
105 mul %0, %2, %0 \n\
106 adds %3, %4, %3 \n\
107 addcs %0, %0, #65536 \n\
108 adds %1, %1, %3, lsl #16 \n\
109 adc %0, %0, %3, lsr #16" \
110 : "=&r" ((USItype) (xh)), \
111 "=r" ((USItype) (xl)), \
112 "=&r" (__t0), "=&r" (__t1), "=r" (__t2) \
113 : "r" ((USItype) (a)), \
114 "r" ((USItype) (b)));}
115#define UMUL_TIME 20
116#define UDIV_TIME 100
117#endif /* __arm__ */
118
119#define __umulsidi3(u, v) \
120 ({DIunion __w; \
121 umul_ppmm (__w.s.high, __w.s.low, u, v); \
122 __w.ll; })
123
124#define __udiv_qrnnd_c(q, r, n1, n0, d) \
125 do { \
126 USItype __d1, __d0, __q1, __q0; \
127 USItype __r1, __r0, __m; \
128 __d1 = __ll_highpart (d); \
129 __d0 = __ll_lowpart (d); \
130 \
131 __r1 = (n1) % __d1; \
132 __q1 = (n1) / __d1; \
133 __m = (USItype) __q1 * __d0; \
134 __r1 = __r1 * __ll_B | __ll_highpart (n0); \
135 if (__r1 < __m) \
136 { \
137 __q1--, __r1 += (d); \
138 if (__r1 >= (d)) /* i.e. we didn't get carry when adding to __r1 */\
139 if (__r1 < __m) \
140 __q1--, __r1 += (d); \
141 } \
142 __r1 -= __m; \
143 \
144 __r0 = __r1 % __d1; \
145 __q0 = __r1 / __d1; \
146 __m = (USItype) __q0 * __d0; \
147 __r0 = __r0 * __ll_B | __ll_lowpart (n0); \
148 if (__r0 < __m) \
149 { \
150 __q0--, __r0 += (d); \
151 if (__r0 >= (d)) \
152 if (__r0 < __m) \
153 __q0--, __r0 += (d); \
154 } \
155 __r0 -= __m; \
156 \
157 (q) = (USItype) __q1 * __ll_B | __q0; \
158 (r) = __r0; \
159 } while (0)
160
161#define UDIV_NEEDS_NORMALIZATION 1
162#define udiv_qrnnd __udiv_qrnnd_c
163
164#define count_leading_zeros(count, x) \
165 do { \
166 USItype __xr = (x); \
167 USItype __a; \
168 \
169 if (SI_TYPE_SIZE <= 32) \
170 { \
171 __a = __xr < ((USItype)1<<2*__BITS4) \
172 ? (__xr < ((USItype)1<<__BITS4) ? 0 : __BITS4) \
173 : (__xr < ((USItype)1<<3*__BITS4) ? 2*__BITS4 : 3*__BITS4); \
174 } \
175 else \
176 { \
177 for (__a = SI_TYPE_SIZE - 8; __a > 0; __a -= 8) \
178 if (((__xr >> __a) & 0xff) != 0) \
179 break; \
180 } \
181 \
182 (count) = SI_TYPE_SIZE - (__clz_tab[__xr >> __a] + __a); \
183 } while (0)