1 #include <fenv.h> 2 #include <limits.h> 3 #include <math.h> 4 #include <stdint.h> 5 #include <stdio.h> 6 7 static void DivideByZero() { 8 // volatile to prevent compiler optimizations. 9 volatile float zero = 0.0f; 10 volatile float result __attribute__((unused)) = 123.0f / zero; 11 } 12 13 int main () { 14 /* Testing lrint. */ 15 fesetround(FE_UPWARD); // lrint/lrintf/lrintl obey the rounding mode. 16 printf("fesetround(FE_UPWARD)\n"); 17 printf("lrint(1234.01): %ld\n", lrint(1234.01)); 18 printf("lrintf(1234.01f): %ld\n", lrintf(1234.01f)); 19 printf("lrintl(1234.01): %ld\n", lrintl(1234.01)); 20 fesetround(FE_TOWARDZERO); // lrint/lrintf/lrintl obey the rounding mode. 21 printf("fesetround(FE_TOWARDZERO)\n"); 22 printf("lrint(1234.01): %ld\n", lrint(1234.01)); 23 printf("lrintf(1234.01f): %ld\n", lrintf(1234.01f)); 24 printf("lrintl(1234.01): %ld\n", lrintl(1234.01)); 25 fesetround(FE_UPWARD); // llrint/llrintf/llrintl obey the rounding mode. 26 printf("fesetround(FE_UPWARD)\n"); 27 printf("llrint(1234.01): %lld\n", llrint(1234.01)); 28 printf("llrintf(1234.01f): %lld\n", llrintf(1234.01f)); 29 printf("llrintf(1234.01f): %lld\n", llrintl(1234.01)); 30 fesetround(FE_TOWARDZERO); // llrint/llrintf/llrintl obey the rounding mode. 31 printf("fesetround(FE_TOWARDZERO)\n"); 32 printf("llrint(1234.01): %lld\n", llrint(1234.01)); 33 printf("llrintf(1234.01f): %lld\n", llrintf(1234.01f)); 34 printf("llrintl(1234.01): %lld\n", llrintl(1234.01)); 35 36 /* Tesing rint. */ 37 fesetround(FE_UPWARD); // rint/rintf/rintl obey the rounding mode. 38 printf("fesetround(FE_UPWARD)\n"); 39 feclearexcept(FE_ALL_EXCEPT); // rint/rintf/rintl do set the FE_INEXACT flag. 40 printf("feclearexcept(FE_ALL_EXCEPT)\n"); 41 printf("rint(1234.0): %f\n", rint(1234.0)); 42 printf("(fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT): %d\n", 43 (fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT)); 44 printf("rint(1234.01): %f\n", rint(1234.01)); 45 printf("(fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT): %d\n", 46 (fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT)); 47 48 feclearexcept(FE_ALL_EXCEPT); // rint/rintf/rintl do set the FE_INEXACT flag. 49 printf("feclearexcept(FE_ALL_EXCEPT)\n"); 50 printf("rintf(1234.0f): %f\n", rintf(1234.0f)); 51 printf("(fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT): %d\n", 52 (fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT)); 53 printf("rintf(1234.01f): %f\n", rintf(1234.01f)); 54 printf("(fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT): %d\n", 55 (fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT)); 56 57 feclearexcept(FE_ALL_EXCEPT); // rint/rintf/rintl do set the FE_INEXACT flag. 58 printf("feclearexcept(FE_ALL_EXCEPT)\n"); 59 printf("rintl(1234.0): %Lf\n", rintl(1234.0)); 60 printf("(fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT): %d\n", 61 (fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT)); 62 printf("rintl(1234.01): %Lf\n", rintl(1234.01)); 63 printf("(fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT): %d\n", 64 (fetestexcept(FE_ALL_EXCEPT) & FE_INEXACT)); 65 66 fesetround(FE_TOWARDZERO); // rint/rintf obey the rounding mode. 67 printf("fesetround(FE_TOWARDZERO)\n"); 68 printf("rint(1234.01): %f\n", rint(1234.01)); 69 printf("rintf(1234.01f): %f\n", rintf(1234.01f)); 70 printf("rintl(1234.01): %Lf\n", rintl(1234.01)); 71 72 /* Testing nearbyint. */ 73 fesetround(FE_UPWARD); // nearbyint/nearbyintf/nearbyintl obey the rounding mode. 74 printf("fesetround(FE_UPWARD)\n"); 75 feclearexcept(FE_ALL_EXCEPT); // nearbyint/nearbyintf/nearbyintl don't set the FE_INEXACT flag. 76 printf("feclearexcept(FE_ALL_EXCEPT)\n"); 77 printf("nearbyint(1234.0): %f\n", nearbyint(1234.0)); 78 printf("nearbyint(1234.01): %f\n", nearbyint(1234.01)); 79 80 feclearexcept(FE_ALL_EXCEPT); 81 printf("feclearexcept(FE_ALL_EXCEPT)\n"); 82 printf("nearbyintf(1234.0f): %f\n", nearbyintf(1234.0f)); 83 printf("nearbyintf(1234.01f): %f\n", nearbyintf(1234.01f)); 84 85 feclearexcept(FE_ALL_EXCEPT); // nearbyint/nearbyintf/nearbyintl don't set the FE_INEXACT flag. 86 printf("feclearexcept(FE_ALL_EXCEPT)\n"); 87 printf("nearbyintl(1234.0f): %Lf\n", nearbyintl(1234.0f)); 88 printf("nearbyintl(1234.01f): %Lf\n", nearbyintl(1234.01f)); 89 90 fesetround(FE_TOWARDZERO); // nearbyint/nearbyintf/nearbyintl obey the rounding mode. 91 printf("fesetround(FE_TOWARDZERO)\n"); 92 printf("nearbyint(1234.01): %f\n", nearbyint(1234.01)); 93 printf("nearbyintf(1234.01f): %f\n", nearbyintf(1234.01f)); 94 printf("nearbyintl(1234.01): %Lf\n", nearbyintl(1234.01)); 95 96 /* Test log. */ 97 printf("log(M_E): %lf\n", log(M_E)); 98 99 /* Test tgamma. */ 100 printf("tgamma(5.0): %lf\n", tgamma(5.0)); 101 102 /* Test cbrt. */ 103 printf("cbrt(27.0): %lf\n", cbrt(27.0)); 104 105 /* Test dividing by zero. */ 106 // Clearing clears. 107 printf("feclearexcept(FE_ALL_EXCEPT): %d\n", feclearexcept(FE_ALL_EXCEPT)); 108 109 // Dividing by zero sets FE_DIVBYZERO. 110 DivideByZero(); 111 int raised = fetestexcept(FE_DIVBYZERO | FE_OVERFLOW); 112 printf("raised: %d\n", raised); 113 114 return 0; 115 } 116
