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Diffstat (limited to 'newlib/libm/common/s_isnan.c')
| -rw-r--r-- | newlib/libm/common/s_isnan.c | 206 |
1 files changed, 0 insertions, 206 deletions
diff --git a/newlib/libm/common/s_isnan.c b/newlib/libm/common/s_isnan.c deleted file mode 100644 index 5ae6c9b81..000000000 --- a/newlib/libm/common/s_isnan.c +++ /dev/null @@ -1,206 +0,0 @@ - -/* @(#)s_isnan.c 5.1 93/09/24 */ -/* - * ==================================================== - * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. - * - * Developed at SunPro, a Sun Microsystems, Inc. business. - * Permission to use, copy, modify, and distribute this - * software is freely granted, provided that this notice - * is preserved. - * ==================================================== - */ - -/* -FUNCTION -<<fpclassify>>, <<isfinite>>, <<isinf>>, <<isnan>>, and <<isnormal>>--floating-point classification macros; <<finite>>, <<finitef>>, <<isinf>>, <<isinff>>, <<isnan>>, <<isnanf>>--test for exceptional numbers - -@c C99 (start -INDEX - fpclassify -INDEX - isfinite -INDEX - isinf -INDEX - isnan -INDEX - isnormal -@c C99 end) -@c SUSv2 (start -INDEX - isnan -INDEX - isinf -INDEX - finite - -INDEX - isnanf -INDEX - isinff -INDEX - finitef -@c SUSv2 end) - -ANSI_SYNOPSIS - [C99 standard macros:] - #include <math.h> - int fpclassify(real-floating <[x]>); - int isfinite(real-floating <[x]>); - int isinf(real-floating <[x]>); - int isnan(real-floating <[x]>); - int isnormal(real-floating <[x]>); - - [Archaic SUSv2 functions:] - #include <ieeefp.h> - int isnan(double <[arg]>); - int isinf(double <[arg]>); - int finite(double <[arg]>); - int isnanf(float <[arg]>); - int isinff(float <[arg]>); - int finitef(float <[arg]>); - -DESCRIPTION -<<fpclassify>>, <<isfinite>>, <<isinf>>, <<isnan>>, and <<isnormal>> are macros -defined for use in classifying floating-point numbers. This is a help because -of special "values" like NaN and infinities. In the synopses shown, -"real-floating" indicates that the argument is an expression of real floating -type. These function-like macros are C99 and POSIX-compliant, and should be -used instead of the now-archaic SUSv2 functions. - -The <<fpclassify>> macro classifies its argument value as NaN, infinite, normal, -subnormal, zero, or into another implementation-defined category. First, an -argument represented in a format wider than its semantic type is converted to -its semantic type. Then classification is based on the type of the argument. -The <<fpclassify>> macro returns the value of the number classification macro -appropriate to the value of its argument: - -o+ -o FP_INFINITE - <[x]> is either plus or minus infinity; -o FP_NAN - <[x]> is "Not A Number" (plus or minus); -o FP_NORMAL - <[x]> is a "normal" number (i.e. is none of the other special forms); -o FP_SUBNORMAL - <[x]> is too small be stored as a regular normalized number (i.e. loss of precision is likely); or -o FP_ZERO - <[x]> is 0 (either plus or minus). -o- - -The "<<is>>" set of macros provide a useful set of shorthand ways for -classifying floating-point numbers, providing the following equivalent -relations: - -o+ -o <<isfinite>>(<[x]>) -returns non-zero if <[x]> is finite. (It is equivalent to -(<<fpclassify>>(<[x]>) != FP_INFINITE && <<fpclassify>>(<[x]>) != FP_NAN).) - -o <<isinf>>(<[x]>) -returns non-zero if <[x]> is infinite. (It is equivalent to -(<<fpclassify>>(<[x]>) == FP_INFINITE).) - -o <<isnan>>(<[x]>) -returns non-zero if <[x]> is NaN. (It is equivalent to -(<<fpclassify>>(<[x]>) == FP_NAN).) - -o <<isnormal>>(<[x]>) -returns non-zero if <[x]> is normal. (It is equivalent to -(<<fpclassify>>(<[x]>) == FP_NORMAL).) -o- - - The archaic SUSv2 functions provide information on the floating-point - argument supplied. - - There are five major number formats ("exponent" referring to the - biased exponent in the binary-encoded number): - o+ - o zero - A number which contains all zero bits, excluding the sign bit. - o subnormal - A number with a zero exponent but a nonzero fraction. - o normal - A number with an exponent and a fraction. - o infinity - A number with an all 1's exponent and a zero fraction. - o NAN - A number with an all 1's exponent and a nonzero fraction. - - o- - - <<isnan>> returns 1 if the argument is a nan. <<isinf>> - returns 1 if the argument is infinity. <<finite>> returns 1 if the - argument is zero, subnormal or normal. - - The <<isnanf>>, <<isinff>> and <<finitef>> functions perform the same - operations as their <<isnan>>, <<isinf>> and <<finite>> - counterparts, but on single-precision floating-point numbers. - - It should be noted that the C99 standard dictates that <<isnan>> - and <<isinf>> are macros that operate on multiple types of - floating-point. The SUSv2 standard declares <<isnan>> as - a function taking double. Newlib has decided to declare - them both as macros in math.h and as functions in ieeefp.h to - maintain backward compatibility. - -RETURNS -@comment Formatting note: "$@" forces a new line -The fpclassify macro returns the value corresponding to the appropriate FP_ macro.@* -The isfinite macro returns nonzero if <[x]> is finite, else 0.@* -The isinf macro returns nonzero if <[x]> is infinite, else 0.@* -The isnan macro returns nonzero if <[x]> is an NaN, else 0.@* -The isnormal macro returns nonzero if <[x]> has a normal value, else 0. - -PORTABILITY -math.h macros are C99, POSIX. - -ieeefp.h funtions are outdated and should be avoided. - -QUICKREF - isnan - pure -QUICKREF - isinf - pure -QUICKREF - finite - pure -QUICKREF - isnan - pure -QUICKREF - isinf - pure -QUICKREF - finite - pure -*/ - -/* - * isnan(x) returns 1 is x is nan, else 0; - * no branching! - * - * The C99 standard dictates that isnan is a macro taking - * multiple floating-point types while the SUSv2 standard - * notes it is a function taking a double argument. Newlib - * has chosen to implement it as a macro in <math.h> and - * declare it as a function in <ieeefp.h>. - */ - -#include "fdlibm.h" -#include <ieeefp.h> - -#ifndef _DOUBLE_IS_32BITS - -#ifdef __STDC__ - int isnan(double x) -#else - int isnan(x) - double x; -#endif -{ - __int32_t hx,lx; - EXTRACT_WORDS(hx,lx,x); - hx &= 0x7fffffff; - hx |= (__uint32_t)(lx|(-lx))>>31; - hx = 0x7ff00000 - hx; - return (int)(((__uint32_t)(hx))>>31); -} - -#endif /* _DOUBLE_IS_32BITS */ |