use signbit for vasnprintf

[Bruno Haible]

This makes use of the signbit macro in the vasnprintf module, as proposed by
Paul.

2007-04-06  Bruno Haible  <address@hidden>

        * lib/vasnprintf.c: Include <math.h>. Don't include float+.h.
        (VASNPRINTF): Use signbit for faster determination whether to print a
        minus sign.
        * modules/vasnprintf (Files): Remove lib/float+.h.
        * modules/fprintf-posix (Depends-on): Add signbit.
        * modules/snprintf-posix (Depends-on): Likewise.
        * modules/sprintf-posix (Depends-on): Likewise.
        * modules/vasnprintf-posix (Depends-on): Likewise.
        * modules/vasprintf-posix (Depends-on): Likewise.
        * modules/vfprintf-posix (Depends-on): Likewise.
        * modules/vsnprintf-posix (Depends-on): Likewise.
        * modules/vsprintf-posix (Depends-on): Likewise.

*** lib/vasnprintf.c    6 Apr 2007 14:36:56 -0000       1.38
--- lib/vasnprintf.c    6 Apr 2007 21:15:59 -0000
***************
*** 54,60 ****
  #include "xsize.h"
  
  #if NEED_PRINTF_DIRECTIVE_A && !defined IN_LIBINTL
! # include "float+.h"
  # include "isnan.h"
  # include "printf-frexp.h"
  # include "isnanl-nolibm.h"
--- 54,60 ----
  #include "xsize.h"
  
  #if NEED_PRINTF_DIRECTIVE_A && !defined IN_LIBINTL
! # include <math.h>
  # include "isnan.h"
  # include "printf-frexp.h"
  # include "isnanl-nolibm.h"
***************
*** 445,466 ****
  
                        BEGIN_LONG_DOUBLE_ROUNDING ();
  
!                       if (arg < 0.0L)
                          {
                            sign = -1;
                            arg = -arg;
                          }
-                       else if (arg == 0.0L)
-                         {
-                           /* Distinguish 0.0L and -0.0L.  */
-                           static long double plus_zero = 0.0L;
-                           long double arg_mem = arg;
-                           if (memcmp (&plus_zero, &arg_mem, SIZEOF_LDBL) != 0)
-                             {
-                               sign = -1;
-                               arg = -arg;
-                             }
-                         }
  
                        if (sign < 0)
                          *p++ = '-';
--- 445,455 ----
  
                        BEGIN_LONG_DOUBLE_ROUNDING ();
  
!                       if (signbit (arg)) /* arg < 0.0L or negative zero */
                          {
                            sign = -1;
                            arg = -arg;
                          }
  
                        if (sign < 0)
                          *p++ = '-';
***************
*** 590,611 ****
                      {
                        int sign = 0;
  
!                       if (arg < 0.0)
                          {
                            sign = -1;
                            arg = -arg;
                          }
-                       else if (arg == 0.0)
-                         {
-                           /* Distinguish 0.0 and -0.0.  */
-                           static double plus_zero = 0.0;
-                           double arg_mem = arg;
-                           if (memcmp (&plus_zero, &arg_mem, SIZEOF_DBL) != 0)
-                             {
-                               sign = -1;
-                               arg = -arg;
-                             }
-                         }
  
                        if (sign < 0)
                          *p++ = '-';
--- 579,589 ----
                      {
                        int sign = 0;
  
!                       if (signbit (arg)) /* arg < 0.0 or negative zero */
                          {
                            sign = -1;
                            arg = -arg;
                          }
  
                        if (sign < 0)
                          *p++ = '-';
*** modules/fprintf-posix       25 Mar 2007 02:30:04 -0000      1.2
--- modules/fprintf-posix       6 Apr 2007 21:15:59 -0000
***************
*** 14,19 ****
--- 14,20 ----
  isnanl-nolibm
  printf-frexp
  printf-frexpl
+ signbit
  fpucw
  
  configure.ac:
*** modules/snprintf-posix      25 Mar 2007 02:30:04 -0000      1.2
--- modules/snprintf-posix      6 Apr 2007 21:15:59 -0000
***************
*** 13,18 ****
--- 13,19 ----
  isnanl-nolibm
  printf-frexp
  printf-frexpl
+ signbit
  fpucw
  
  configure.ac:
*** modules/sprintf-posix       25 Mar 2007 02:30:04 -0000      1.2
--- modules/sprintf-posix       6 Apr 2007 21:15:59 -0000
***************
*** 13,18 ****
--- 13,19 ----
  isnanl-nolibm
  printf-frexp
  printf-frexpl
+ signbit
  fpucw
  
  configure.ac:
*** modules/vasnprintf  6 Apr 2007 14:36:56 -0000       1.14
--- modules/vasnprintf  6 Apr 2007 21:15:59 -0000
***************
*** 6,12 ****
  lib/printf-args.c
  lib/printf-parse.h
  lib/printf-parse.c
- lib/float+.h
  lib/vasnprintf.h
  lib/vasnprintf.c
  lib/asnprintf.c
--- 6,11 ----
*** modules/vasnprintf-posix    25 Mar 2007 02:30:04 -0000      1.2
--- modules/vasnprintf-posix    6 Apr 2007 21:15:59 -0000
***************
*** 12,17 ****
--- 12,18 ----
  isnanl-nolibm
  printf-frexp
  printf-frexpl
+ signbit
  fpucw
  
  configure.ac:
*** modules/vasprintf-posix     25 Mar 2007 02:30:04 -0000      1.2
--- modules/vasprintf-posix     6 Apr 2007 21:15:59 -0000
***************
*** 12,17 ****
--- 12,18 ----
  isnanl-nolibm
  printf-frexp
  printf-frexpl
+ signbit
  fpucw
  
  configure.ac:
*** modules/vfprintf-posix      25 Mar 2007 02:30:04 -0000      1.2
--- modules/vfprintf-posix      6 Apr 2007 21:15:59 -0000
***************
*** 14,19 ****
--- 14,20 ----
  isnanl-nolibm
  printf-frexp
  printf-frexpl
+ signbit
  fpucw
  
  configure.ac:
*** modules/vsnprintf-posix     25 Mar 2007 02:30:04 -0000      1.2
--- modules/vsnprintf-posix     6 Apr 2007 21:15:59 -0000
***************
*** 13,18 ****
--- 13,19 ----
  isnanl-nolibm
  printf-frexp
  printf-frexpl
+ signbit
  fpucw
  
  configure.ac:
*** modules/vsprintf-posix      25 Mar 2007 02:30:04 -0000      1.2
--- modules/vsprintf-posix      6 Apr 2007 21:15:59 -0000
***************
*** 13,18 ****
--- 13,19 ----
  isnanl-nolibm
  printf-frexp
  printf-frexpl
+ signbit
  fpucw
  
  configure.ac: