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authorGuo Mang <mang.guo@intel.com>2017-08-02 09:54:47 +0800
committerGuo Mang <mang.guo@intel.com>2017-09-05 19:45:08 +0800
commit6c128c65b5ec0e5b8b5a0ccb165f3afd29e485f8 (patch)
tree444372d92a0ae8991fe4d15eb3937df43690dfda /StdLib/LibC/Math/e_log10.c
parentb207c6434d7a5a4502975d322312e07017e8a8cb (diff)
downloadedk2-platforms-6c128c65b5ec0e5b8b5a0ccb165f3afd29e485f8.tar.xz
Remove core packages since we can get them from edk2 repository
Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Guo Mang <mang.guo@intel.com>
Diffstat (limited to 'StdLib/LibC/Math/e_log10.c')
-rw-r--r--StdLib/LibC/Math/e_log10.c106
1 files changed, 0 insertions, 106 deletions
diff --git a/StdLib/LibC/Math/e_log10.c b/StdLib/LibC/Math/e_log10.c
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--- a/StdLib/LibC/Math/e_log10.c
+++ /dev/null
@@ -1,106 +0,0 @@
-/** @file
- Compute the base 10 logrithm of x.
-
- Copyright (c) 2010 - 2011, Intel Corporation. All rights reserved.<BR>
- This program and the accompanying materials are licensed and made available under
- the terms and conditions of the BSD License that accompanies this distribution.
- The full text of the license may be found at
- http://opensource.org/licenses/bsd-license.
-
- THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
- WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
-
- * ====================================================
- * 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.
- * ====================================================
-
- e_log10.c 5.1 93/09/24
- NetBSD: e_log10.c,v 1.12 2002/05/26 22:01:51 wiz Exp
-**/
-#include <LibConfig.h>
-#include <sys/EfiCdefs.h>
-
-/* __ieee754_log10(x)
- * Return the base 10 logarithm of x
- *
- * Method :
- * Let log10_2hi = leading 40 bits of log10(2) and
- * log10_2lo = log10(2) - log10_2hi,
- * ivln10 = 1/log(10) rounded.
- * Then
- * n = ilogb(x),
- * if(n<0) n = n+1;
- * x = scalbn(x,-n);
- * log10(x) := n*log10_2hi + (n*log10_2lo + ivln10*log(x))
- *
- * Note 1:
- * To guarantee log10(10**n)=n, where 10**n is normal, the rounding
- * mode must set to Round-to-Nearest.
- * Note 2:
- * [1/log(10)] rounded to 53 bits has error .198 ulps;
- * log10 is monotonic at all binary break points.
- *
- * Special cases:
- * log10(x) is NaN with signal if x < 0;
- * log10(+INF) is +INF with no signal; log10(0) is -INF with signal;
- * log10(NaN) is that NaN with no signal;
- * log10(10**N) = N for N=0,1,...,22.
- *
- * Constants:
- * The hexadecimal values are the intended ones for the following constants.
- * The decimal values may be used, provided that the compiler will convert
- * from decimal to binary accurately enough to produce the hexadecimal values
- * shown.
- */
-
-#include "math.h"
-#include "math_private.h"
-#include <errno.h>
-
-#if defined(_MSC_VER) /* Handle Microsoft VC++ compiler specifics. */
- // potential divide by 0 -- near line 80, (x-x)/zero is on purpose
- #pragma warning ( disable : 4723 )
-#endif
-
-static const double
-two54 = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */
-ivln10 = 4.34294481903251816668e-01, /* 0x3FDBCB7B, 0x1526E50E */
-log10_2hi = 3.01029995663611771306e-01, /* 0x3FD34413, 0x509F6000 */
-log10_2lo = 3.69423907715893078616e-13; /* 0x3D59FEF3, 0x11F12B36 */
-
-static const double zero = 0.0;
-
-double
-__ieee754_log10(double x)
-{
- double y,z;
- int32_t i,k,hx;
- u_int32_t lx;
-
- EXTRACT_WORDS(hx,lx,x);
-
- k=0;
- if (hx < 0x00100000) { /* x < 2**-1022 */
- if (((hx&0x7fffffff)|lx)==0)
- return -two54/zero; /* log(+-0)=-inf */
- if (hx<0) {
- errno = EDOM;
- return (x-x)/zero; /* log(-#) = NaN */
- }
- k -= 54; x *= two54; /* subnormal number, scale up x */
- GET_HIGH_WORD(hx,x);
- }
- if (hx >= 0x7ff00000) return x+x;
- k += (hx>>20)-1023;
- i = ((u_int32_t)k&0x80000000)>>31;
- hx = (hx&0x000fffff)|((0x3ff-i)<<20);
- y = (double)(k+i);
- SET_HIGH_WORD(x,hx);
- z = y*log10_2lo + ivln10*__ieee754_log(x);
- return z+y*log10_2hi;
-}