1// RUN: %clang_builtins %s %librt -o %t && %run %t
2
3#define DOUBLE_PRECISION
4#include <fenv.h>
5#include <float.h>
6#include <limits.h>
7#include <math.h>
8#include <stdio.h>
9#include "fp_lib.h"
10
11int test__compiler_rt_scalbn(const char *mode, fp_t x, int y) {
12#if defined(__ve__)
13 if (fpclassify(x) == FP_SUBNORMAL)
14 return 0;
15#endif
16 fp_t crt_value = __compiler_rt_scalbn(x, y);
17 fp_t libm_value = scalbn(x: x, n: y);
18 // Consider +/-0 unequal, but disregard the sign/payload of NaN.
19 if (toRep(x: crt_value) != toRep(x: libm_value) &&
20 !(crt_isnan(crt_value) && crt_isnan(libm_value))) {
21 printf(format: "error: [%s] in __compiler_rt_scalbn(%a [%llX], %d) = %a [%llX] "
22 "!= %a [%llX]\n",
23 mode, x, (unsigned long long)toRep(x), y,
24 crt_value, (unsigned long long)toRep(x: crt_value),
25 libm_value, (unsigned long long)toRep(x: libm_value));
26 return 1;
27 }
28 return 0;
29}
30
31fp_t cases[] = {
32 -NAN, NAN, -INFINITY, INFINITY, -0.0, 0.0, -1, 1, -2, 2,
33 DBL_TRUE_MIN, DBL_TRUE_MIN*7, DBL_MIN, DBL_MAX,
34 -1.001, 1.001, -1.002, 1.002, 1.e-6, -1.e-6,
35 0x1.0p-1021,
36 0x1.0p-1022,
37 0x1.0p-1023, // subnormal
38 0x1.0p-1024, // subnormal
39};
40
41int iterate_cases(const char *mode) {
42 const unsigned N = sizeof(cases) / sizeof(cases[0]);
43 unsigned i;
44 for (i = 0; i < N; ++i) {
45 int j;
46 for (j = -5; j <= 5; ++j) {
47 if (test__compiler_rt_scalbn(mode, x: cases[i], y: j)) return 1;
48 }
49 if (test__compiler_rt_scalbn(mode, x: cases[i], y: -10000)) return 1;
50 if (test__compiler_rt_scalbn(mode, x: cases[i], y: 10000)) return 1;
51 if (test__compiler_rt_scalbn(mode, x: cases[i], INT_MIN)) return 1;
52 if (test__compiler_rt_scalbn(mode, x: cases[i], INT_MAX)) return 1;
53 }
54 return 0;
55}
56
57int main() {
58 if (iterate_cases(mode: "default")) return 1;
59
60 // Rounding mode tests on supported architectures. __compiler_rt_scalbn
61 // should have the same rounding behavior as double-precision multiplication.
62#if (defined(__arm__) || defined(__aarch64__)) && defined(__ARM_FP) || \
63 defined(__i386__) || defined(__x86_64__)
64// Skip these tests on Windows because the UCRT scalbn function always behaves
65// as if the default rounding mode is set (FE_TONEAREST).
66// Also skip for newlib because although its scalbn function does respect the
67// rounding mode, where the tests trigger an underflow or overflow using a
68// large exponent the result is rounded in the opposite direction to that which
69// would be expected in the (FE_UPWARD) and (FE_DOWNWARD) modes.
70# if !defined(_WIN32) && !defined(_NEWLIB_VERSION)
71 fesetround(FE_UPWARD);
72 if (iterate_cases(mode: "FE_UPWARD")) return 1;
73
74 fesetround(FE_DOWNWARD);
75 if (iterate_cases(mode: "FE_DOWNWARD")) return 1;
76
77 fesetround(FE_TOWARDZERO);
78 if (iterate_cases(mode: "FE_TOWARDZERO")) return 1;
79#endif
80
81 fesetround(FE_TONEAREST);
82 if (iterate_cases(mode: "FE_TONEAREST")) return 1;
83#endif
84
85 return 0;
86}
87

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