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-rw-r--r--sysdeps/ieee754/dbl-64/s_exp2.c130
-rw-r--r--sysdeps/ieee754/flt-32/s_exp2f.c128
2 files changed, 0 insertions, 258 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_exp2.c b/sysdeps/ieee754/dbl-64/s_exp2.c
deleted file mode 100644
index d02af15ecc..0000000000
--- a/sysdeps/ieee754/dbl-64/s_exp2.c
+++ /dev/null
@@ -1,130 +0,0 @@
-/* Double-precision floating point 2^x.
- Copyright (C) 1997, 1998, 2000 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Geoffrey Keating <geoffk@ozemail.com.au>
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Library General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Library General Public License for more details.
-
- You should have received a copy of the GNU Library General Public
- License along with the GNU C Library; see the file COPYING.LIB. If not,
- write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
-
-/* The basic design here is from
- Shmuel Gal and Boris Bachelis, "An Accurate Elementary Mathematical
- Library for the IEEE Floating Point Standard", ACM Trans. Math. Soft.,
- 17 (1), March 1991, pp. 26-45.
- It has been slightly modified to compute 2^x instead of e^x.
- */
-#ifndef _GNU_SOURCE
-#define _GNU_SOURCE
-#endif
-#include <stdlib.h>
-#include <float.h>
-#include <ieee754.h>
-#include <math.h>
-#include <fenv.h>
-#include <inttypes.h>
-#include <math_private.h>
-
-#include "t_exp2.h"
-
-static const volatile double TWO1023 = 8.988465674311579539e+307;
-static const volatile double TWOM1000 = 9.3326361850321887899e-302;
-
-double
-__ieee754_exp2 (double x)
-{
- static const double himark = (double) DBL_MAX_EXP;
- static const double lomark = (double) (DBL_MIN_EXP - DBL_MANT_DIG - 1) - 1.0;
-
- /* Check for usual case. */
- if (isless (x, himark) && isgreater (x, lomark))
- {
- static const double THREEp42 = 13194139533312.0;
- int tval, unsafe;
- double rx, x22, result;
- union ieee754_double ex2_u, scale_u;
- fenv_t oldenv;
-
- feholdexcept (&oldenv);
-#ifdef FE_TONEAREST
- /* If we don't have this, it's too bad. */
- fesetround (FE_TONEAREST);
-#endif
-
- /* 1. Argument reduction.
- Choose integers ex, -256 <= t < 256, and some real
- -1/1024 <= x1 <= 1024 so that
- x = ex + t/512 + x1.
-
- First, calculate rx = ex + t/512. */
- rx = x + THREEp42;
- rx -= THREEp42;
- x -= rx; /* Compute x=x1. */
- /* Compute tval = (ex*512 + t)+256.
- Now, t = (tval mod 512)-256 and ex=tval/512 [that's mod, NOT %; and
- /-round-to-nearest not the usual c integer /]. */
- tval = (int) (rx * 512.0 + 256.0);
-
- /* 2. Adjust for accurate table entry.
- Find e so that
- x = ex + t/512 + e + x2
- where -1e6 < e < 1e6, and
- (double)(2^(t/512+e))
- is accurate to one part in 2^-64. */
-
- /* 'tval & 511' is the same as 'tval%512' except that it's always
- positive.
- Compute x = x2. */
- x -= exp2_deltatable[tval & 511];
-
- /* 3. Compute ex2 = 2^(t/512+e+ex). */
- ex2_u.d = exp2_accuratetable[tval & 511];
- tval >>= 9;
- unsafe = abs(tval) >= -DBL_MIN_EXP - 1;
- ex2_u.ieee.exponent += tval >> unsafe;
- scale_u.d = 1.0;
- scale_u.ieee.exponent += tval - (tval >> unsafe);
-
- /* 4. Approximate 2^x2 - 1, using a fourth-degree polynomial,
- with maximum error in [-2^-10-2^-30,2^-10+2^-30]
- less than 10^-19. */
-
- x22 = (((.0096181293647031180
- * x + .055504110254308625)
- * x + .240226506959100583)
- * x + .69314718055994495) * ex2_u.d;
-
- /* 5. Return (2^x2-1) * 2^(t/512+e+ex) + 2^(t/512+e+ex). */
- fesetenv (&oldenv);
-
- result = x22 * x + ex2_u.d;
-
- if (!unsafe)
- return result;
- else
- return result * scale_u.d;
- }
- /* Exceptional cases: */
- else if (isless (x, himark))
- {
- if (__isinf (x))
- /* e^-inf == 0, with no error. */
- return 0;
- else
- /* Underflow */
- return TWOM1000 * TWOM1000;
- }
- else
- /* Return x, if x is a NaN or Inf; or overflow, otherwise. */
- return TWO1023*x;
-}
diff --git a/sysdeps/ieee754/flt-32/s_exp2f.c b/sysdeps/ieee754/flt-32/s_exp2f.c
deleted file mode 100644
index 4d529ea285..0000000000
--- a/sysdeps/ieee754/flt-32/s_exp2f.c
+++ /dev/null
@@ -1,128 +0,0 @@
-/* Single-precision floating point 2^x.
- Copyright (C) 1997, 1998, 2000 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Geoffrey Keating <geoffk@ozemail.com.au>
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Library General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Library General Public License for more details.
-
- You should have received a copy of the GNU Library General Public
- License along with the GNU C Library; see the file COPYING.LIB. If not,
- write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
-
-/* The basic design here is from
- Shmuel Gal and Boris Bachelis, "An Accurate Elementary Mathematical
- Library for the IEEE Floating Point Standard", ACM Trans. Math. Soft.,
- 17 (1), March 1991, pp. 26-45.
- It has been slightly modified to compute 2^x instead of e^x, and for
- single-precision.
- */
-#ifndef _GNU_SOURCE
-# define _GNU_SOURCE
-#endif
-#include <stdlib.h>
-#include <float.h>
-#include <ieee754.h>
-#include <math.h>
-#include <fenv.h>
-#include <inttypes.h>
-#include <math_private.h>
-
-#include "t_exp2f.h"
-
-static const volatile float TWOM100 = 7.88860905e-31;
-static const volatile float TWO127 = 1.7014118346e+38;
-
-float
-__ieee754_exp2f (float x)
-{
- static const float himark = (float) FLT_MAX_EXP;
- static const float lomark = (float) (FLT_MIN_EXP - FLT_MANT_DIG - 1) - 1.0;
-
- /* Check for usual case. */
- if (isless (x, himark) && isgreater (x, lomark))
- {
- static const float THREEp14 = 49152.0;
- int tval, unsafe;
- float rx, x22, result;
- union ieee754_float ex2_u, scale_u;
- fenv_t oldenv;
-
- feholdexcept (&oldenv);
-#ifdef FE_TONEAREST
- /* If we don't have this, it's too bad. */
- fesetround (FE_TONEAREST);
-#endif
-
- /* 1. Argument reduction.
- Choose integers ex, -128 <= t < 128, and some real
- -1/512 <= x1 <= 1/512 so that
- x = ex + t/512 + x1.
-
- First, calculate rx = ex + t/256. */
- rx = x + THREEp14;
- rx -= THREEp14;
- x -= rx; /* Compute x=x1. */
- /* Compute tval = (ex*256 + t)+128.
- Now, t = (tval mod 256)-128 and ex=tval/256 [that's mod, NOT %; and
- /-round-to-nearest not the usual c integer /]. */
- tval = (int) (rx * 256.0f + 128.0f);
-
- /* 2. Adjust for accurate table entry.
- Find e so that
- x = ex + t/256 + e + x2
- where -7e-4 < e < 7e-4, and
- (float)(2^(t/256+e))
- is accurate to one part in 2^-64. */
-
- /* 'tval & 255' is the same as 'tval%256' except that it's always
- positive.
- Compute x = x2. */
- x -= __exp2f_deltatable[tval & 255];
-
- /* 3. Compute ex2 = 2^(t/255+e+ex). */
- ex2_u.f = __exp2f_atable[tval & 255];
- tval >>= 8;
- unsafe = abs(tval) >= -FLT_MIN_EXP - 1;
- ex2_u.ieee.exponent += tval >> unsafe;
- scale_u.f = 1.0;
- scale_u.ieee.exponent += tval - (tval >> unsafe);
-
- /* 4. Approximate 2^x2 - 1, using a second-degree polynomial,
- with maximum error in [-2^-9 - 2^-14, 2^-9 + 2^-14]
- less than 1.3e-10. */
-
- x22 = (.24022656679f * x + .69314736128f) * ex2_u.f;
-
- /* 5. Return (2^x2-1) * 2^(t/512+e+ex) + 2^(t/512+e+ex). */
- fesetenv (&oldenv);
-
- result = x22 * x + ex2_u.f;
-
- if (!unsafe)
- return result;
- else
- return result * scale_u.f;
- }
- /* Exceptional cases: */
- else if (isless (x, himark))
- {
- if (__isinff (x))
- /* e^-inf == 0, with no error. */
- return 0;
- else
- /* Underflow */
- return TWOM100 * TWOM100;
- }
- else
- /* Return x, if x is a NaN or Inf; or overflow, otherwise. */
- return TWO127*x;
-}
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