compiler-rt/test/builtins/Unit/compiler_rt_logbf_test.c

   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
   9 int 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);
  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("error: in __compiler_rt_logb(%a [%X]) = %a [%X] !=  %a [%X]\n", x,
  22            toRep(x), crt_value, toRep(crt_value), libm_value,
  23            toRep(libm_value));
  24     return 1;
  25   }
  26   return 0;
  27 }
  28
  29 double 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
  34 int 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(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(fromRep(x))) return 1;
  46     if (test__compiler_rt_logbf(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(fromRep(x))) return 1;
  53     if (test__compiler_rt_logbf(fromRep(signBit ^ x))) return 1;
  54     x >>= 1;
  55   }
  56
  57   return 0;
  58 }