1 // RUN: %clang_builtins %s %librt -o %t && %run %t
2
3 #define SINGLE_PRECISION
4 #include "fp_lib.h"
5 #include "int_math.h"
6 #include <math.h>
7 #include <stdio.h>
8
test__compiler_rt_logbf(fp_t x)9 int test__compiler_rt_logbf(fp_t x) {
10 fp_t crt_value = __compiler_rt_logbf(x);
11 fp_t libm_value = logbf(x);
12 // `!=` operator on fp_t returns false for NaNs so also check if operands are
13 // both NaN. We don't do `toRepr(crt_value) != toRepr(libm_value)` because
14 // that treats different representations of NaN as not equivalent.
15 if (crt_value != libm_value &&
16 !(crt_isnan(crt_value) && crt_isnan(libm_value))) {
17 printf("error: in __compiler_rt_logb(%a [%X]) = %a [%X] != %a [%X]\n", x,
18 toRep(x), crt_value, toRep(crt_value), libm_value,
19 toRep(libm_value));
20 return 1;
21 }
22 return 0;
23 }
24
25 double cases[] = {
26 1.e-6, -1.e-6, NAN, -NAN, INFINITY, -INFINITY, -1,
27 -0.0, 0.0, 1, -2, 2, -0.5, 0.5,
28 };
29
main()30 int main() {
31 const unsigned N = sizeof(cases) / sizeof(cases[0]);
32 unsigned i;
33 for (i = 0; i < N; ++i) {
34 if (test__compiler_rt_logbf(cases[i])) return 1;
35 }
36
37 // Test a moving 1 bit, especially to handle denormal values.
38 // Test the negation as well.
39 rep_t x = signBit;
40 while (x) {
41 if (test__compiler_rt_logbf(fromRep(x))) return 1;
42 if (test__compiler_rt_logbf(fromRep(signBit ^ x))) return 1;
43 x >>= 1;
44 }
45 // Also try a couple moving ones
46 x = signBit | (signBit >> 1) | (signBit >> 2);
47 while (x) {
48 if (test__compiler_rt_logbf(fromRep(x))) return 1;
49 if (test__compiler_rt_logbf(fromRep(signBit ^ x))) return 1;
50 x >>= 1;
51 }
52
53 return 0;
54 }
55