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
9int test__compiler_rt_logbf(fp_t x) {
10#if defined(__ve__)
11 if (fpclassify(x) == FP_SUBNORMAL)
12 return 0;
13#endif
14 fp_t crt_value = __compiler_rt_logbf(x);
15 fp_t libm_value = logbf(x: x);
16 // `!=` operator on fp_t returns false for NaNs so also check if operands are
17 // both NaN. We don't do `toRepr(crt_value) != toRepr(libm_value)` because
18 // that treats different representations of NaN as not equivalent.
19 if (crt_value != libm_value &&
20 !(crt_isnan(crt_value) && crt_isnan(libm_value))) {
21 printf(format: "error: in __compiler_rt_logb(%a [%X]) = %a [%X] != %a [%X]\n", x,
22 toRep(x), crt_value, toRep(x: crt_value), libm_value,
23 toRep(x: libm_value));
24 return 1;
25 }
26 return 0;
27}
28
29double cases[] = {
30 1.e-6, -1.e-6, NAN, -NAN, INFINITY, -INFINITY, -1,
31 -0.0, 0.0, 1, -2, 2, -0.5, 0.5,
32};
33
34int main() {
35 const unsigned N = sizeof(cases) / sizeof(cases[0]);
36 unsigned i;
37 for (i = 0; i < N; ++i) {
38 if (test__compiler_rt_logbf(x: cases[i])) return 1;
39 }
40
41 // Test a moving 1 bit, especially to handle denormal values.
42 // Test the negation as well.
43 rep_t x = signBit;
44 while (x) {
45 if (test__compiler_rt_logbf(x: fromRep(x))) return 1;
46 if (test__compiler_rt_logbf(x: fromRep(signBit ^ x))) return 1;
47 x >>= 1;
48 }
49 // Also try a couple moving ones
50 x = signBit | (signBit >> 1) | (signBit >> 2);
51 while (x) {
52 if (test__compiler_rt_logbf(x: fromRep(x))) return 1;
53 if (test__compiler_rt_logbf(x: fromRep(signBit ^ x))) return 1;
54 x >>= 1;
55 }
56
57 return 0;
58}
59

source code of compiler-rt/test/builtins/Unit/compiler_rt_logbf_test.c