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: 0; #elif defined(TRIO_COMPILER_MSVC) || defined(TRIO_COMPILER_BCB) /* * Microsoft Visual C++ and Borland C++ Builder have an _fpclass() * function that can be used to detect infinity. */ return ((_fpclass(number) == _FPCLASS_PINF) ? 1 : ((_fpclass(number) == _FPCLASS_NINF) ? -1 : 0));#elif defined(USE_IEEE_754) /* * Examine IEEE 754 bit-pattern. Infinity must have a special exponent * pattern, and an empty mantissa. */ int has_mantissa; int is_special_quantity; is_special_quantity = trio_is_special_quantity(number, &has_mantissa); return (is_special_quantity && !has_mantissa) ? ((number < 0.0) ? -1 : 1) : 0;#else /* * Fallback solution. */ int status; # if defined(TRIO_PLATFORM_UNIX) void (*signal_handler)(int) = signal(SIGFPE, SIG_IGN);# endif double infinity = trio_pinf(); status = ((number == infinity) ? 1 : ((number == -infinity) ? -1 : 0)); # if defined(TRIO_PLATFORM_UNIX) signal(SIGFPE, signal_handler);# endif return status; #endif}#if 0 /* Temporary fix - this routine is not used anywhere *//** Check for finity. @param number An arbitrary floating-point number. @return Boolean value indicating whether or not the number is a finite.*/TRIO_PUBLIC inttrio_isfiniteTRIO_ARGS1((number), double number){#if defined(TRIO_COMPILER_SUPPORTS_C99) && defined(isfinite) /* * C99 defines isfinite() as a macro. */ return isfinite(number); #elif defined(TRIO_COMPILER_MSVC) || defined(TRIO_COMPILER_BCB) /* * Microsoft Visual C++ and Borland C++ Builder use _finite(). */ return _finite(number);#elif defined(USE_IEEE_754) /* * Examine IEEE 754 bit-pattern. For finity we do not care about the * mantissa. */ int dummy; return (! trio_is_special_quantity(number, &dummy));#else /* * Fallback solution. */ return ((trio_isinf(number) == 0) && (trio_isnan(number) == 0)); #endif}#endif/* * The sign of NaN is always false */TRIO_PUBLIC inttrio_fpclassify_and_signbitTRIO_ARGS2((number, is_negative), double number, int *is_negative){#if defined(fpclassify) && defined(signbit) /* * C99 defines fpclassify() and signbit() as a macros */ *is_negative = signbit(number); switch (fpclassify(number)) { case FP_NAN: return TRIO_FP_NAN; case FP_INFINITE: return TRIO_FP_INFINITE; case FP_SUBNORMAL: return TRIO_FP_SUBNORMAL; case FP_ZERO: return TRIO_FP_ZERO; default: return TRIO_FP_NORMAL; }#else# if defined(TRIO_COMPILER_DECC) /* * DECC has an fp_class() function. */# define TRIO_FPCLASSIFY(n) fp_class(n)# define TRIO_QUIET_NAN FP_QNAN# define TRIO_SIGNALLING_NAN FP_SNAN# define TRIO_POSITIVE_INFINITY FP_POS_INF# define TRIO_NEGATIVE_INFINITY FP_NEG_INF# define TRIO_POSITIVE_SUBNORMAL FP_POS_DENORM# define TRIO_NEGATIVE_SUBNORMAL FP_NEG_DENORM# define TRIO_POSITIVE_ZERO FP_POS_ZERO# define TRIO_NEGATIVE_ZERO FP_NEG_ZERO# define TRIO_POSITIVE_NORMAL FP_POS_NORM# define TRIO_NEGATIVE_NORMAL FP_NEG_NORM # elif defined(TRIO_COMPILER_MSVC) || defined(TRIO_COMPILER_BCB) /* * Microsoft Visual C++ and Borland C++ Builder have an _fpclass() * function. */# define TRIO_FPCLASSIFY(n) _fpclass(n)# define TRIO_QUIET_NAN _FPCLASS_QNAN# define TRIO_SIGNALLING_NAN _FPCLASS_SNAN# define TRIO_POSITIVE_INFINITY _FPCLASS_PINF# define TRIO_NEGATIVE_INFINITY _FPCLASS_NINF# define TRIO_POSITIVE_SUBNORMAL _FPCLASS_PD# define TRIO_NEGATIVE_SUBNORMAL _FPCLASS_ND# define TRIO_POSITIVE_ZERO _FPCLASS_PZ# define TRIO_NEGATIVE_ZERO _FPCLASS_NZ# define TRIO_POSITIVE_NORMAL _FPCLASS_PN# define TRIO_NEGATIVE_NORMAL _FPCLASS_NN # elif defined(FP_PLUS_NORM) /* * HP-UX 9.x and 10.x have an fpclassify() function, that is different * from the C99 fpclassify() macro supported on HP-UX 11.x. * * AIX has class() for C, and _class() for C++, which returns the * same values as the HP-UX fpclassify() function. */# if defined(TRIO_PLATFORM_AIX)# if defined(__cplusplus)# define TRIO_FPCLASSIFY(n) _class(n)# else# define TRIO_FPCLASSIFY(n) class(n)# endif# else# define TRIO_FPCLASSIFY(n) fpclassify(n)# endif# define TRIO_QUIET_NAN FP_QNAN# define TRIO_SIGNALLING_NAN FP_SNAN# define TRIO_POSITIVE_INFINITY FP_PLUS_INF# define TRIO_NEGATIVE_INFINITY FP_MINUS_INF# define TRIO_POSITIVE_SUBNORMAL FP_PLUS_DENORM# define TRIO_NEGATIVE_SUBNORMAL FP_MINUS_DENORM# define TRIO_POSITIVE_ZERO FP_PLUS_ZERO# define TRIO_NEGATIVE_ZERO FP_MINUS_ZERO# define TRIO_POSITIVE_NORMAL FP_PLUS_NORM# define TRIO_NEGATIVE_NORMAL FP_MINUS_NORM# endif# if defined(TRIO_FPCLASSIFY) switch (TRIO_FPCLASSIFY(number)) { case TRIO_QUIET_NAN: case TRIO_SIGNALLING_NAN: *is_negative = TRIO_FALSE; /* NaN has no sign */ return TRIO_FP_NAN; case TRIO_POSITIVE_INFINITY: *is_negative = TRIO_FALSE; return TRIO_FP_INFINITE; case TRIO_NEGATIVE_INFINITY: *is_negative = TRIO_TRUE; return TRIO_FP_INFINITE; case TRIO_POSITIVE_SUBNORMAL: *is_negative = TRIO_FALSE; return TRIO_FP_SUBNORMAL; case TRIO_NEGATIVE_SUBNORMAL: *is_negative = TRIO_TRUE; return TRIO_FP_SUBNORMAL; case TRIO_POSITIVE_ZERO: *is_negative = TRIO_FALSE; return TRIO_FP_ZERO; case TRIO_NEGATIVE_ZERO: *is_negative = TRIO_TRUE; return TRIO_FP_ZERO; case TRIO_POSITIVE_NORMAL: *is_negative = TRIO_FALSE; return TRIO_FP_NORMAL; case TRIO_NEGATIVE_NORMAL: *is_negative = TRIO_TRUE; return TRIO_FP_NORMAL; default: /* Just in case... */ *is_negative = (number < 0.0); return TRIO_FP_NORMAL; } # else /* * Fallback solution. */ int rc; if (number == 0.0) { /* * In IEEE 754 the sign of zero is ignored in comparisons, so we * have to handle this as a special case by examining the sign bit * directly. */# if defined(USE_IEEE_754) *is_negative = trio_is_negative(number);# else *is_negative = TRIO_FALSE; /* FIXME */# endif return TRIO_FP_ZERO; } if (trio_isnan(number)) { *is_negative = TRIO_FALSE; return TRIO_FP_NAN; } if ((rc = trio_isinf(number))) { *is_negative = (rc == -1); return TRIO_FP_INFINITE; } if ((number > 0.0) && (number < DBL_MIN)) { *is_negative = TRIO_FALSE; return TRIO_FP_SUBNORMAL; } if ((number < 0.0) && (number > -DBL_MIN)) { *is_negative = TRIO_TRUE; return TRIO_FP_SUBNORMAL; } *is_negative = (number < 0.0); return TRIO_FP_NORMAL; # endif#endif}/** Examine the sign of a number. @param number An arbitrary floating-point number. @return Boolean value indicating whether or not the number has the sign bit set (i.e. is negative).*/TRIO_PUBLIC inttrio_signbitTRIO_ARGS1((number), double number){ int is_negative; (void)trio_fpclassify_and_signbit(number, &is_negative); return is_negative;}#if 0 /* Temporary fix - this routine is not used in libxml *//** Examine the class of a number. @param number An arbitrary floating-point number. @return Enumerable value indicating the class of @p number*/TRIO_PUBLIC inttrio_fpclassifyTRIO_ARGS1((number), double number){ int dummy; return trio_fpclassify_and_signbit(number, &dummy);}#endif/** @} SpecialQuantities *//************************************************************************* * For test purposes. * * Add the following compiler option to include this test code. * * Unix : -DSTANDALONE * VMS : /DEFINE=(STANDALONE) */#if defined(STANDALONE)# include <stdio.h>static TRIO_CONST char *getClassificationTRIO_ARGS1((type), int type){ switch (type) { case TRIO_FP_INFINITE: return "FP_INFINITE"; case TRIO_FP_NAN: return "FP_NAN"; case TRIO_FP_NORMAL: return "FP_NORMAL"; case TRIO_FP_SUBNORMAL: return "FP_SUBNORMAL"; case TRIO_FP_ZERO: return "FP_ZERO"; default: return "FP_UNKNOWN"; }}static voidprint_classTRIO_ARGS2((prefix, number), TRIO_CONST char *prefix, double number){ printf("%-6s: %s %-15s %g\n", prefix, trio_signbit(number) ? "-" : "+", getClassification(TRIO_FPCLASSIFY(number)), number);}int main(TRIO_NOARGS){ double my_nan; double my_pinf; double my_ninf;# if defined(TRIO_PLATFORM_UNIX) void (*signal_handler) TRIO_PROTO((int));# endif my_nan = trio_nan(); my_pinf = trio_pinf(); my_ninf = trio_ninf(); print_class("Nan", my_nan); print_class("PInf", my_pinf); print_class("NInf", my_ninf); print_class("PZero", 0.0); print_class("NZero", -0.0); print_class("PNorm", 1.0); print_class("NNorm", -1.0); print_class("PSub", 1.01e-307 - 1.00e-307); print_class("NSub", 1.00e-307 - 1.01e-307); printf("NaN : %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n", my_nan, ((unsigned char *)&my_nan)[0], ((unsigned char *)&my_nan)[1], ((unsigned char *)&my_nan)[2], ((unsigned char *)&my_nan)[3], ((unsigned char *)&my_nan)[4], ((unsigned char *)&my_nan)[5], ((unsigned char *)&my_nan)[6], ((unsigned char *)&my_nan)[7], trio_isnan(my_nan), trio_isinf(my_nan)); printf("PInf: %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n", my_pinf, ((unsigned char *)&my_pinf)[0], ((unsigned char *)&my_pinf)[1], ((unsigned char *)&my_pinf)[2], ((unsigned char *)&my_pinf)[3], ((unsigned char *)&my_pinf)[4], ((unsigned char *)&my_pinf)[5], ((unsigned char *)&my_pinf)[6], ((unsigned char *)&my_pinf)[7], trio_isnan(my_pinf), trio_isinf(my_pinf)); printf("NInf: %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n", my_ninf, ((unsigned char *)&my_ninf)[0], ((unsigned char *)&my_ninf)[1], ((unsigned char *)&my_ninf)[2], ((unsigned char *)&my_ninf)[3], ((unsigned char *)&my_ninf)[4], ((unsigned char *)&my_ninf)[5], ((unsigned char *)&my_ninf)[6], ((unsigned char *)&my_ninf)[7], trio_isnan(my_ninf), trio_isinf(my_ninf)); # if defined(TRIO_PLATFORM_UNIX) signal_handler = signal(SIGFPE, SIG_IGN);# endif my_pinf = DBL_MAX + DBL_MAX; my_ninf = -my_pinf; my_nan = my_pinf / my_pinf;# if defined(TRIO_PLATFORM_UNIX) signal(SIGFPE, signal_handler);# endif printf("NaN : %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n", my_nan, ((unsigned char *)&my_nan)[0], ((unsigned char *)&my_nan)[1], ((unsigned char *)&my_nan)[2], ((unsigned char *)&my_nan)[3], ((unsigned char *)&my_nan)[4], ((unsigned char *)&my_nan)[5], ((unsigned char *)&my_nan)[6], ((unsigned char *)&my_nan)[7], trio_isnan(my_nan), trio_isinf(my_nan)); printf("PInf: %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n", my_pinf, ((unsigned char *)&my_pinf)[0], ((unsigned char *)&my_pinf)[1], ((unsigned char *)&my_pinf)[2], ((unsigned char *)&my_pinf)[3], ((unsigned char *)&my_pinf)[4], ((unsigned char *)&my_pinf)[5], ((unsigned char *)&my_pinf)[6], ((unsigned char *)&my_pinf)[7], trio_isnan(my_pinf), trio_isinf(my_pinf)); printf("NInf: %4g 0x%02x%02x%02x%02x%02x%02x%02x%02x (%2d, %2d)\n", my_ninf, ((unsigned char *)&my_ninf)[0], ((unsigned char *)&my_ninf)[1], ((unsigned char *)&my_ninf)[2], ((unsigned char *)&my_ninf)[3], ((unsigned char *)&my_ninf)[4], ((unsigned char *)&my_ninf)[5], ((unsigned char *)&my_ninf)[6], ((unsigned char *)&my_ninf)[7], trio_isnan(my_ninf), trio_isinf(my_ninf)); return 0;}#endif
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