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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
commitf7eac6eb504f4baf13dbb4d26717942df050ebe6 (patch)
tree95ff129c06c7f6f246a5e2bfa489ba6382659d19 /sysdeps/libm-ieee754/s_rint.c
parent1521668f2afae1dc2ef5d7ffaeb84353b36874dd (diff)
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/s_rint.c')
-rw-r--r--sysdeps/libm-ieee754/s_rint.c87
1 files changed, 87 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_rint.c b/sysdeps/libm-ieee754/s_rint.c
new file mode 100644
index 0000000000..e24feaf1ac
--- /dev/null
+++ b/sysdeps/libm-ieee754/s_rint.c
@@ -0,0 +1,87 @@
+/* @(#)s_rint.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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: s_rint.c,v 1.8 1995/05/10 20:48:04 jtc Exp $";
+#endif
+
+/*
+ * rint(x)
+ * Return x rounded to integral value according to the prevailing
+ * rounding mode.
+ * Method:
+ * Using floating addition.
+ * Exception:
+ * Inexact flag raised if x not equal to rint(x).
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const double
+#else
+static double
+#endif
+TWO52[2]={
+ 4.50359962737049600000e+15, /* 0x43300000, 0x00000000 */
+ -4.50359962737049600000e+15, /* 0xC3300000, 0x00000000 */
+};
+
+#ifdef __STDC__
+ double __rint(double x)
+#else
+ double __rint(x)
+ double x;
+#endif
+{
+ int32_t i0,j0,sx;
+ u_int32_t i,i1;
+ double w,t;
+ EXTRACT_WORDS(i0,i1,x);
+ sx = (i0>>31)&1;
+ j0 = ((i0>>20)&0x7ff)-0x3ff;
+ if(j0<20) {
+ if(j0<0) {
+ if(((i0&0x7fffffff)|i1)==0) return x;
+ i1 |= (i0&0x0fffff);
+ i0 &= 0xfffe0000;
+ i0 |= ((i1|-i1)>>12)&0x80000;
+ SET_HIGH_WORD(x,i0);
+ w = TWO52[sx]+x;
+ t = w-TWO52[sx];
+ GET_HIGH_WORD(i0,t);
+ SET_HIGH_WORD(t,(i0&0x7fffffff)|(sx<<31));
+ return t;
+ } else {
+ i = (0x000fffff)>>j0;
+ if(((i0&i)|i1)==0) return x; /* x is integral */
+ i>>=1;
+ if(((i0&i)|i1)!=0) {
+ if(j0==19) i1 = 0x40000000; else
+ i0 = (i0&(~i))|((0x20000)>>j0);
+ }
+ }
+ } else if (j0>51) {
+ if(j0==0x400) return x+x; /* inf or NaN */
+ else return x; /* x is integral */
+ } else {
+ i = ((u_int32_t)(0xffffffff))>>(j0-20);
+ if((i1&i)==0) return x; /* x is integral */
+ i>>=1;
+ if((i1&i)!=0) i1 = (i1&(~i))|((0x40000000)>>(j0-20));
+ }
+ INSERT_WORDS(x,i0,i1);
+ w = TWO52[sx]+x;
+ return w-TWO52[sx];
+}
+weak_alias (__rint, rint)