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authorRoland McGrath <roland@gnu.org>1996-03-05 21:41:30 +0000
committerRoland McGrath <roland@gnu.org>1996-03-05 21:41:30 +0000
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parent1521668f2afae1dc2ef5d7ffaeb84353b36874dd (diff)
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Mon Mar 4 20:54:40 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>
* Makeconfig ($(common-objpfx)config.make): Depend on config.h.in. Mon Mar 4 17:35:09 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu> * hurd/catch-signal.c (hurd_safe_memmove): New function. (hurd_safe_copyin, hurd_safe_copyout): New functions. * hurd/hurd/sigpreempt.h: Declare them. Sun Mar 3 08:43:44 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu> Replace math code with fdlibm from Sun as modified for netbsd by JT Conklin and Ian Taylor, including x86 FPU support. * sysdeps/libm-ieee754, sysdeps/libm-i387: New directories. * math/math_private.h: New file. * sysdeps/i386/fpu/Implies: New file. * sysdeps/ieee754/Implies: New file. * math/machine/asm.h, math/machine/endian.h: New files. * math/Makefile, math/math.h: Rewritten. * mathcalls.h, math/mathcalls.h: New file, broken out of math.h. * math/finite.c: File removed. * sysdeps/generic/Makefile [$(subdir)=math]: Frobnication removed. * math/test-math.c: Include errno.h and string.h. * sysdeps/unix/bsd/dirstream.h: File removed. * sysdeps/unix/bsd/readdir.c: File removed.
Diffstat (limited to 'sysdeps/libm-ieee754/e_log10f.c')
-rw-r--r--sysdeps/libm-ieee754/e_log10f.c67
1 files changed, 67 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/e_log10f.c b/sysdeps/libm-ieee754/e_log10f.c
new file mode 100644
index 0000000000..2082a763bb
--- /dev/null
+++ b/sysdeps/libm-ieee754/e_log10f.c
@@ -0,0 +1,67 @@
+/* e_log10f.c -- float version of e_log10.c.
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: e_log10f.c,v 1.5 1995/05/10 20:45:53 jtc Exp $";
+#endif
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const float
+#else
+static float
+#endif
+two25 = 3.3554432000e+07, /* 0x4c000000 */
+ivln10 = 4.3429449201e-01, /* 0x3ede5bd9 */
+log10_2hi = 3.0102920532e-01, /* 0x3e9a2080 */
+log10_2lo = 7.9034151668e-07; /* 0x355427db */
+
+#ifdef __STDC__
+static const float zero = 0.0;
+#else
+static float zero = 0.0;
+#endif
+
+#ifdef __STDC__
+ float __ieee754_log10f(float x)
+#else
+ float __ieee754_log10f(x)
+ float x;
+#endif
+{
+ float y,z;
+ int32_t i,k,hx;
+
+ GET_FLOAT_WORD(hx,x);
+
+ k=0;
+ if (hx < 0x00800000) { /* x < 2**-126 */
+ if ((hx&0x7fffffff)==0)
+ return -two25/zero; /* log(+-0)=-inf */
+ if (hx<0) return (x-x)/zero; /* log(-#) = NaN */
+ k -= 25; x *= two25; /* subnormal number, scale up x */
+ GET_FLOAT_WORD(hx,x);
+ }
+ if (hx >= 0x7f800000) return x+x;
+ k += (hx>>23)-127;
+ i = ((u_int32_t)k&0x80000000)>>31;
+ hx = (hx&0x007fffff)|((0x7f-i)<<23);
+ y = (float)(k+i);
+ SET_FLOAT_WORD(x,hx);
+ z = y*log10_2lo + ivln10*__ieee754_logf(x);
+ return z+y*log10_2hi;
+}