xref: /netbsd-src/regress/lib/libc/divrem/divremtest.c (revision 9fbd88883c38d0c0fbfcbe66d76fe6b0fab3f9de)
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <unistd.h>
4 #include <fcntl.h>
5 #include <stdint.h>
6 #include <assert.h>
7 #include <time.h>
8 
9 #define	KLE	3	// exponent for k and l salt values
10 #define	NEARBY	600	// all numbers +-NEARBY 0 and INTxx_MIN will be tried
11 #define	RANDOMCOUNT 300000	// number of random(3)-based cases to run
12 
13 #define	 IM(x)	 ((intmax_t)(x))
14 #define	UIM(x)	((uintmax_t)(x))
15 
16 #define TEST(id, a, b, c)                             			\
17     if (b) {                            				\
18 	c = (a) / (b);                        				\
19 	printf(id "%16jx / %16jx => %16jx\n", UIM(a), UIM(b), UIM(c));  \
20 	c = (a) % (b);                        				\
21 	printf(id "%16jx / %16jx => %16jx\n", UIM(a), UIM(b), UIM(c));  \
22     }
23 
24 #define	T64S(a, b, c)	TEST("64 ", (a), (b), (c))
25 #define	T64U(a, b, c)	TEST("64U", (a), (b), (c))
26 
27 union {
28 	char	ranstate[128];
29 	long	alignme;
30 } ranalign;
31 
32 int enable_time_output;
33 
34 void mark_time(const int phase)
35 {
36 static	time_t startphase;
37 	time_t t;
38 
39 	t = time(NULL);
40 	if (enable_time_output && phase != 0) {
41 		fprintf(stderr, "phase %d/6: %5d seconds\n", phase,
42 		    (int)(t - startphase));
43 		fflush(stderr);
44 	}
45 	startphase = t;
46 }
47 
48 int main(int ac, char **av)
49 {
50      int32_t a32, b32, sr32;
51     uint32_t ur32;
52      intmax_t a64, b64, sr64;
53     uintmax_t ur64;
54      int i, j, k, l;
55 
56     enable_time_output = ac <= 1;
57     mark_time(0);
58     for(i = KLE; i <= 30; ++i) {
59 	a32 = 1 << i;
60 	for(j = KLE; j <= 30; ++j) {
61 	    b32 = 1 << j;
62 	    for(k = -(1 << KLE); k <= 1 << KLE; ++k) {
63 		for(l = -(1 << KLE); l <= 1 << KLE; ++l) {
64 		    TEST("32 ",  a32 + k,  b32 + l, sr32);
65 		    TEST("32 ",  a32 + k, -(b32 + l), sr32);
66 		    TEST("32 ", -(a32 + k),   b32 + l, sr32);
67 		    TEST("32 ", -(a32 + k), -(b32 + l), sr32);
68 		    assert((1U << i) + k >= 0);
69 		    assert((1U << j) + l >= 0);
70 		    TEST("32U", (1U << i) + k, (1U << j) + l, ur32);
71 		}
72 	    }
73 	}
74     }
75 
76     mark_time(1);
77     for(a32 = -NEARBY; a32 < NEARBY; ++a32) {
78 	for(b32 = -NEARBY; b32 < NEARBY; ++b32) {
79 	    TEST("32 ", a32, b32, sr32);
80 	    if (a32 >= 0 && b32 >= 0)
81 		TEST("32U", (unsigned)a32, (unsigned)b32, ur32);
82 	}
83     }
84     mark_time(2);
85     for(a32 = INT32_MIN; a32 < INT32_MIN + NEARBY; ++a32) {
86 	for(b32 = INT32_MIN; b32 < INT32_MIN + NEARBY; ++b32)
87 	    TEST("32 ", a32, b32, sr32);
88 	for(b32 = -NEARBY; b32 < NEARBY; ++b32)
89 	    if (a32 != INT32_MIN || b32 != -1)
90 		TEST("32 ", a32, b32, sr32);
91     }
92 
93     mark_time(3);
94     if (sizeof(intmax_t) == 4)
95 	exit(0);
96     for(i = KLE; i <= 62; ++i) {
97 	a64 = IM(1) << i;
98 	for(j = KLE; j <= 62; ++j) {
99 	    b64 = IM(1) << j;
100 	    for(k = -(1 << KLE); k <= 1 << KLE; ++k) {
101 		for(l = -(1 << KLE); l <= 1 << KLE; ++l) {
102 		    T64S( a64 + k,  b64 + l, sr64);
103 		    T64S( a64 + k, -b64 + l, sr64);
104 		    T64S(-a64 + k,  b64 + l, sr64);
105 		    T64S(-a64 + k, -b64 + l, sr64);
106 		    T64U(UIM(a64) + k, UIM(b64) + l, ur64);
107 		}
108 	    }
109 	}
110     }
111 
112     mark_time(4);
113     for(a64 = -(1 << KLE); a64 < 1 << KLE; ++a64) {
114 	for(b64 = -(1 << KLE); b64 < 1 << KLE; ++b64) {
115 	    TEST("64 ", a64, b64, sr64);
116 	    if (a64 >= 0 && b64 >= 0)
117 		TEST("64U", (unsigned)a64, (unsigned)b64, ur64);
118 	}
119     }
120     for(a64 = INT64_MIN; a64 < INT64_MIN + NEARBY; ++a64) {
121 	for(b64 = INT64_MIN; b64 < INT64_MIN + NEARBY; ++b64)
122 	    TEST("64 ", a64, b64, sr64);
123 	for(b64 = -NEARBY; b64 < NEARBY; ++b64)
124 	    if (a64 != INT64_MIN || b64 != -1)
125 		TEST("64 ", a64, b64, sr64);
126     }
127     mark_time(5);
128     initstate(1UL, ranalign.ranstate, sizeof ranalign.ranstate);
129     for(i = 0; i < RANDOMCOUNT; ++i) {
130 	int32_t low32 = random();
131 	int64_t low64 = (intmax_t)random() << 32 | low32;
132 
133 	a32 = random();
134 	b32 = random();
135 	a64 = ((intmax_t)random() << 32) | a32;
136 	b64 = ((intmax_t)random() << 32) | b32;
137 	TEST("32 ", a32, b32, sr32);
138 	TEST("32u", (unsigned)a32 + low32, (unsigned)b32 + low32, ur32);
139 	TEST("32 ", -a32 - 1, b32, sr32);
140 	TEST("32 ", a32, -b32, sr32);
141 	if (a32 != INT32_MAX || b32 != 1)
142 	    TEST("32 ", -a32 - 1, -b32, sr32);
143 	TEST("64 ", a64, b64, sr64);
144 	TEST("64u", (unsigned)a64 + low64, (unsigned)b64 + low64, ur64);
145 	TEST("64 ", -a64 - 1, b64, sr64);
146 	TEST("64 ", a64, -b64, sr64);
147 	if (a64 != INT64_MAX || b64 != 1)
148 	    TEST("64 ", -a64 - 1, -b64, sr64);
149     }
150     mark_time(6);
151     exit(0);
152     return 0;
153 }
154