1// RUN: %clang_builtins %s %librt -o %t && %run %t
2
3#define DOUBLE_PRECISION
4#include <math.h>
5#include <stdio.h>
6#include "fp_lib.h"
7
8int test__compiler_rt_logb(fp_t x) {
9 fp_t crt_value = __compiler_rt_logb(x);
10 fp_t libm_value = logb(x);
11 // Compare the values, considering all NaNs equivalent, as the spec doesn't
12 // specify the NaN signedness/payload.
13 if (crt_value != libm_value &&
14 !(crt_isnan(crt_value) && crt_isnan(libm_value))) {
15 printf("error: in __compiler_rt_logb(%a [%lX]) = %a [%lX] != %a [%lX]\n",
16 x, toRep(x), crt_value, toRep(crt_value), libm_value,
17 toRep(libm_value));
18 return 1;
19 }
20 return 0;
21}
22
23double cases[] = {
24 1.e-6, -1.e-6, NAN, -NAN, INFINITY, -INFINITY, -1,
25 -0.0, 0.0, 1, -2, 2, -0.5, 0.5,
26};
27
28#ifndef __GLIBC_PREREQ
29#define __GLIBC_PREREQ(x, y) 0
30#endif
31
32int main() {
33 // Do not the run the compiler-rt logb test case if using GLIBC version
34 // < 2.23. Older versions might not compute to the same value as the
35 // compiler-rt value.
36#if __GLIBC_PREREQ(2, 23)
37 const unsigned N = sizeof(cases) / sizeof(cases[0]);
38 unsigned i;
39 for (i = 0; i < N; ++i) {
40 if (test__compiler_rt_logb(cases[i])) return 1;
41 }
42
43 // Test a moving 1 bit, especially to handle denormal values.
44 // Test the negation as well.
45 rep_t x = signBit;
46 while (x) {
47 if (test__compiler_rt_logb(fromRep(x))) return 1;
48 if (test__compiler_rt_logb(fromRep(signBit ^ x))) return 1;
49 x >>= 1;
50 }
51 // Also try a couple moving ones
52 x = signBit | (signBit >> 1) | (signBit >> 2);
53 while (x) {
54 if (test__compiler_rt_logb(fromRep(x))) return 1;
55 if (test__compiler_rt_logb(fromRep(signBit ^ x))) return 1;
56 x >>= 1;
57 }
58#else
59 printf("skipped\n");
60#endif
61
62 return 0;
63}
64