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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_floor.c
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/s_floor.c')
-rw-r--r--sysdeps/libm-ieee754/s_floor.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_floor.c b/sysdeps/libm-ieee754/s_floor.c
new file mode 100644
index 0000000000..4dabc77a78
--- /dev/null
+++ b/sysdeps/libm-ieee754/s_floor.c
@@ -0,0 +1,82 @@
+/* @(#)s_floor.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_floor.c,v 1.8 1995/05/10 20:47:20 jtc Exp $";
+#endif
+
+/*
+ * floor(x)
+ * Return x rounded toward -inf to integral value
+ * Method:
+ *	Bit twiddling.
+ * Exception:
+ *	Inexact flag raised if x not equal to floor(x).
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const double huge = 1.0e300;
+#else
+static double huge = 1.0e300;
+#endif
+
+#ifdef __STDC__
+	double __floor(double x)
+#else
+	double __floor(x)
+	double x;
+#endif
+{
+	int32_t i0,i1,j0;
+	u_int32_t i,j;
+	EXTRACT_WORDS(i0,i1,x);
+	j0 = ((i0>>20)&0x7ff)-0x3ff;
+	if(j0<20) {
+	    if(j0<0) { 	/* raise inexact if x != 0 */
+		if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */
+		    if(i0>=0) {i0=i1=0;} 
+		    else if(((i0&0x7fffffff)|i1)!=0)
+			{ i0=0xbff00000;i1=0;}
+		}
+	    } else {
+		i = (0x000fffff)>>j0;
+		if(((i0&i)|i1)==0) return x; /* x is integral */
+		if(huge+x>0.0) {	/* raise inexact flag */
+		    if(i0<0) i0 += (0x00100000)>>j0;
+		    i0 &= (~i); i1=0;
+		}
+	    }
+	} 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 */
+	    if(huge+x>0.0) { 		/* raise inexact flag */
+		if(i0<0) {
+		    if(j0==20) i0+=1; 
+		    else {
+			j = i1+(1<<(52-j0));
+			if(j<i1) i0 +=1 ; 	/* got a carry */
+			i1=j;
+		    }
+		}
+		i1 &= (~i);
+	    }
+	}
+	INSERT_WORDS(x,i0,i1);
+	return x;
+}
+weak_alias (__floor, floor)