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Diffstat (limited to 'lib/libm/fdlibm.h')
| -rw-r--r-- | lib/libm/fdlibm.h | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/lib/libm/fdlibm.h b/lib/libm/fdlibm.h new file mode 100644 index 0000000000..529a3975ac --- /dev/null +++ b/lib/libm/fdlibm.h @@ -0,0 +1,227 @@ +/* + * This file is part of the Micro Python project, http://micropython.org/ + * + * This file is adapted from from newlib-nano-2, the newlib/libm/common/fdlib.h, + * available from https://github.com/32bitmicro/newlib-nano-2. The main change + * is removal of anything to do with double precision. + * + * Appropriate copyright headers are reproduced below. + */ + +/* @(#)fdlibm.h 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. + * ==================================================== + */ + +#include <math.h> + +/* Default to XOPEN_MODE. */ +#define _XOPEN_MODE + +/* Most routines need to check whether a float is finite, infinite, or not a + number, and many need to know whether the result of an operation will + overflow. These conditions depend on whether the largest exponent is + used for NaNs & infinities, or whether it's used for finite numbers. The + macros below wrap up that kind of information: + + FLT_UWORD_IS_FINITE(X) + True if a positive float with bitmask X is finite. + + FLT_UWORD_IS_NAN(X) + True if a positive float with bitmask X is not a number. + + FLT_UWORD_IS_INFINITE(X) + True if a positive float with bitmask X is +infinity. + + FLT_UWORD_MAX + The bitmask of FLT_MAX. + + FLT_UWORD_HALF_MAX + The bitmask of FLT_MAX/2. + + FLT_UWORD_EXP_MAX + The bitmask of the largest finite exponent (129 if the largest + exponent is used for finite numbers, 128 otherwise). + + FLT_UWORD_LOG_MAX + The bitmask of log(FLT_MAX), rounded down. This value is the largest + input that can be passed to exp() without producing overflow. + + FLT_UWORD_LOG_2MAX + The bitmask of log(2*FLT_MAX), rounded down. This value is the + largest input than can be passed to cosh() without producing + overflow. + + FLT_LARGEST_EXP + The largest biased exponent that can be used for finite numbers + (255 if the largest exponent is used for finite numbers, 254 + otherwise) */ + +#ifdef _FLT_LARGEST_EXPONENT_IS_NORMAL +#define FLT_UWORD_IS_FINITE(x) 1 +#define FLT_UWORD_IS_NAN(x) 0 +#define FLT_UWORD_IS_INFINITE(x) 0 +#define FLT_UWORD_MAX 0x7fffffff +#define FLT_UWORD_EXP_MAX 0x43010000 +#define FLT_UWORD_LOG_MAX 0x42b2d4fc +#define FLT_UWORD_LOG_2MAX 0x42b437e0 +#define HUGE ((float)0X1.FFFFFEP128) +#else +#define FLT_UWORD_IS_FINITE(x) ((x)<0x7f800000L) +#define FLT_UWORD_IS_NAN(x) ((x)>0x7f800000L) +#define FLT_UWORD_IS_INFINITE(x) ((x)==0x7f800000L) +#define FLT_UWORD_MAX 0x7f7fffffL +#define FLT_UWORD_EXP_MAX 0x43000000 +#define FLT_UWORD_LOG_MAX 0x42b17217 +#define FLT_UWORD_LOG_2MAX 0x42b2d4fc +#define HUGE ((float)3.40282346638528860e+38) +#endif +#define FLT_UWORD_HALF_MAX (FLT_UWORD_MAX-(1L<<23)) +#define FLT_LARGEST_EXP (FLT_UWORD_MAX>>23) + +/* Many routines check for zero and subnormal numbers. Such things depend + on whether the target supports denormals or not: + + FLT_UWORD_IS_ZERO(X) + True if a positive float with bitmask X is +0. Without denormals, + any float with a zero exponent is a +0 representation. With + denormals, the only +0 representation is a 0 bitmask. + + FLT_UWORD_IS_SUBNORMAL(X) + True if a non-zero positive float with bitmask X is subnormal. + (Routines should check for zeros first.) + + FLT_UWORD_MIN + The bitmask of the smallest float above +0. Call this number + REAL_FLT_MIN... + + FLT_UWORD_EXP_MIN + The bitmask of the float representation of REAL_FLT_MIN's exponent. + + FLT_UWORD_LOG_MIN + The bitmask of |log(REAL_FLT_MIN)|, rounding down. + + FLT_SMALLEST_EXP + REAL_FLT_MIN's exponent - EXP_BIAS (1 if denormals are not supported, + -22 if they are). +*/ + +#ifdef _FLT_NO_DENORMALS +#define FLT_UWORD_IS_ZERO(x) ((x)<0x00800000L) +#define FLT_UWORD_IS_SUBNORMAL(x) 0 +#define FLT_UWORD_MIN 0x00800000 +#define FLT_UWORD_EXP_MIN 0x42fc0000 +#define FLT_UWORD_LOG_MIN 0x42aeac50 +#define FLT_SMALLEST_EXP 1 +#else +#define FLT_UWORD_IS_ZERO(x) ((x)==0) +#define FLT_UWORD_IS_SUBNORMAL(x) ((x)<0x00800000L) +#define FLT_UWORD_MIN 0x00000001 +#define FLT_UWORD_EXP_MIN 0x43160000 +#define FLT_UWORD_LOG_MIN 0x42cff1b5 +#define FLT_SMALLEST_EXP -22 +#endif + +#ifdef __STDC__ +#undef __P +#define __P(p) p +#else +#define __P(p) () +#endif + +/* + * set X_TLOSS = pi*2**52, which is possibly defined in <values.h> + * (one may replace the following line by "#include <values.h>") + */ + +#define X_TLOSS 1.41484755040568800000e+16 + +/* Functions that are not documented, and are not in <math.h>. */ + +/* Undocumented float functions. */ +#ifdef _SCALB_INT +extern float scalbf __P((float, int)); +#else +extern float scalbf __P((float, float)); +#endif +extern float significandf __P((float)); + +/* ieee style elementary float functions */ +extern float __ieee754_sqrtf __P((float)); +extern float __ieee754_acosf __P((float)); +extern float __ieee754_acoshf __P((float)); +extern float __ieee754_logf __P((float)); +extern float __ieee754_atanhf __P((float)); +extern float __ieee754_asinf __P((float)); +extern float __ieee754_atan2f __P((float,float)); +extern float __ieee754_expf __P((float)); +extern float __ieee754_coshf __P((float)); +extern float __ieee754_fmodf __P((float,float)); +extern float __ieee754_powf __P((float,float)); +extern float __ieee754_lgammaf_r __P((float,int *)); +extern float __ieee754_gammaf_r __P((float,int *)); +extern float __ieee754_log10f __P((float)); +extern float __ieee754_sinhf __P((float)); +extern float __ieee754_hypotf __P((float,float)); +extern float __ieee754_j0f __P((float)); +extern float __ieee754_j1f __P((float)); +extern float __ieee754_y0f __P((float)); +extern float __ieee754_y1f __P((float)); +extern float __ieee754_jnf __P((int,float)); +extern float __ieee754_ynf __P((int,float)); +extern float __ieee754_remainderf __P((float,float)); +extern __int32_t __ieee754_rem_pio2f __P((float,float*)); +#ifdef _SCALB_INT +extern float __ieee754_scalbf __P((float,int)); +#else +extern float __ieee754_scalbf __P((float,float)); +#endif + +/* float versions of fdlibm kernel functions */ +extern float __kernel_sinf __P((float,float,int)); +extern float __kernel_cosf __P((float,float)); +extern float __kernel_tanf __P((float,float,int)); +extern int __kernel_rem_pio2f __P((float*,float*,int,int,int,const __int32_t*)); + +/* A union which permits us to convert between a float and a 32 bit + int. */ + +typedef union +{ + float value; + __uint32_t word; +} ieee_float_shape_type; + +/* Get a 32 bit int from a float. */ + +#define GET_FLOAT_WORD(i,d) \ +do { \ + ieee_float_shape_type gf_u; \ + gf_u.value = (d); \ + (i) = gf_u.word; \ +} while (0) + +/* Set a float from a 32 bit int. */ + +#define SET_FLOAT_WORD(d,i) \ +do { \ + ieee_float_shape_type sf_u; \ + sf_u.word = (i); \ + (d) = sf_u.value; \ +} while (0) + +/* Macros to avoid undefined behaviour that can arise if the amount + of a shift is exactly equal to the size of the shifted operand. */ + +#define SAFE_LEFT_SHIFT(op,amt) \ + (((amt) < 8 * sizeof(op)) ? ((op) << (amt)) : 0) + +#define SAFE_RIGHT_SHIFT(op,amt) \ + (((amt) < 8 * sizeof(op)) ? ((op) >> (amt)) : 0) |