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4
5#include <stdio.h>
6#include <inttypes.h>
7#include <assert.h>
8
9struct quotient_remainder { int32_t quotient, remainder; };
10
11static struct quotient_remainder div1(int32_t rs, int32_t rt)
12{
13 int32_t lo, hi;
14
15 __asm__ __volatile__ (
16 " div1 $0, %2, %3\n"
17 " mflo1 %0\n"
18 " mfhi1 %1\n"
19 : "=r" (lo), "=r" (hi)
20 : "r" (rs), "r" (rt));
21
22 assert(rs / rt == lo);
23 assert(rs % rt == hi);
24
25 return (struct quotient_remainder) { .quotient = lo, .remainder = hi };
26}
27
28static void verify_div1(int32_t rs, int32_t rt,
29 int32_t expected_quotient,
30 int32_t expected_remainder)
31{
32 struct quotient_remainder qr = div1(rs, rt);
33
34 assert(qr.quotient == expected_quotient);
35 assert(qr.remainder == expected_remainder);
36}
37
38static void verify_div1_negations(int32_t rs, int32_t rt,
39 int32_t expected_quotient,
40 int32_t expected_remainder)
41{
42 verify_div1(rs, rt, expected_quotient, expected_remainder);
43 verify_div1(rs, -rt, -expected_quotient, expected_remainder);
44 verify_div1(-rs, rt, -expected_quotient, -expected_remainder);
45 verify_div1(-rs, -rt, expected_quotient, -expected_remainder);
46}
47
48int main()
49{
50 verify_div1_negations(0, 1, 0, 0);
51 verify_div1_negations(1, 1, 1, 0);
52 verify_div1_negations(1, 2, 0, 1);
53 verify_div1_negations(17, 19, 0, 17);
54 verify_div1_negations(19, 17, 1, 2);
55 verify_div1_negations(77773, 101, 770, 3);
56
57 verify_div1(-0x80000000, 1, -0x80000000, 0);
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69
70 verify_div1(-0x80000000, -1, -0x80000000, 0);
71
72 return 0;
73}
74