From: Ulrich Drepper <drepper@redhat.com>
Date: Fri, 29 Jan 1999 16:55:14 +0000 (+0000)
Subject: (__floor): Copy commentary from bits/mathinclude.h.  Kill unused defines.
X-Git-Tag: upstream/2.30~10627^2~2941
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=92a38c359c748628f33f1352675610755724dbc7;p=external%2Fglibc.git

(__floor): Copy commentary from bits/mathinclude.h.  Kill unused defines.
---

diff --git a/sysdeps/alpha/fpu/s_floor.c b/sysdeps/alpha/fpu/s_floor.c
index c7e1466..146e19b 100644
--- a/sysdeps/alpha/fpu/s_floor.c
+++ b/sysdeps/alpha/fpu/s_floor.c
@@ -17,18 +17,17 @@
    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
    Boston, MA 02111-1307, USA.  */
 
-#ifndef __USE_EXTERN_INLINES
-#define __USE_EXTERN_INLINES
-#endif
-#define __floor __i_floor
-
 #include <math.h>
 
-#undef __floor
+
+/* Use the -inf rounding mode conversion instructions to implement
+   floor.  We note when the exponent is large enough that the value
+   must be integral, as this avoids unpleasant integer overflows.  */
 
 double
 __floor (double x)
 {
+  /* Check not zero since floor(-0) == -0.  */
   if (x != 0 && fabs (x) < 9007199254740992.0)  /* 1 << DBL_MANT_DIG */
     {
       double __tmp1;