68 lines · c
1// RUN: %clang_builtins %s %librt -o %t && %run %t2 3#define DOUBLE_PRECISION4#include <math.h>5#include <stdio.h>6#include "fp_lib.h"7 8int test__compiler_rt_logb(fp_t x) {9#if defined(__ve__)10 if (fpclassify(x) == FP_SUBNORMAL)11 return 0;12#endif13 fp_t crt_value = __compiler_rt_logb(x);14 fp_t libm_value = logb(x);15 // Compare the values, considering all NaNs equivalent, as the spec doesn't16 // specify the NaN signedness/payload.17 if (crt_value != libm_value &&18 !(crt_isnan(crt_value) && crt_isnan(libm_value))) {19 printf("error: in __compiler_rt_logb(%a [%lX]) = %a [%lX] != %a [%lX]\n",20 x, toRep(x), crt_value, toRep(crt_value), libm_value,21 toRep(libm_value));22 return 1;23 }24 return 0;25}26 27double cases[] = {28 1.e-6, -1.e-6, NAN, -NAN, INFINITY, -INFINITY, -1,29 -0.0, 0.0, 1, -2, 2, -0.5, 0.5,30};31 32#ifndef __GLIBC_PREREQ33#define __GLIBC_PREREQ(x, y) 034#endif35 36int main() {37 // Do not the run the compiler-rt logb test case if using GLIBC version38 // < 2.23. Older versions might not compute to the same value as the39 // compiler-rt value.40#if __GLIBC_PREREQ(2, 23)41 const unsigned N = sizeof(cases) / sizeof(cases[0]);42 unsigned i;43 for (i = 0; i < N; ++i) {44 if (test__compiler_rt_logb(cases[i])) return 1;45 }46 47 // Test a moving 1 bit, especially to handle denormal values.48 // Test the negation as well.49 rep_t x = signBit;50 while (x) {51 if (test__compiler_rt_logb(fromRep(x))) return 1;52 if (test__compiler_rt_logb(fromRep(signBit ^ x))) return 1;53 x >>= 1;54 }55 // Also try a couple moving ones56 x = signBit | (signBit >> 1) | (signBit >> 2);57 while (x) {58 if (test__compiler_rt_logb(fromRep(x))) return 1;59 if (test__compiler_rt_logb(fromRep(signBit ^ x))) return 1;60 x >>= 1;61 }62#else63 printf("skipped\n");64#endif65 66 return 0;67}68