PowerPC floating point little-endian [1 of 15]

http://sourceware.org/ml/libc-alpha/2013-08/msg00081.html

This is the first of a series of patches to ban ieee854_long_double
and the ieee854_long_double macros when using IBM long double.  union
ieee854_long_double just isn't correct for IBM long double, especially
when little-endian, and pretending it is OK has allowed a number of
bugs to remain undetected in sysdeps/ieee754/ldbl-128ibm/.

This changes the few places in generic code that use it.

	* stdio-common/printf_size.c (__printf_size): Don't use
	union ieee854_long_double in fpnum union.
	* stdio-common/printf_fphex.c (__printf_fphex): Likewise.  Use
	signbit macro to retrieve sign from long double.
	* stdio-common/printf_fp.c (___printf_fp): Use signbit macro to
	retrieve sign from long double.
	* sysdeps/ieee754/ldbl-128ibm/printf_fphex.c: Adjust for fpnum change.
	* sysdeps/ieee754/ldbl-128/printf_fphex.c: Likewise.
	* sysdeps/ieee754/ldbl-96/printf_fphex.c: Likewise.
	* sysdeps/x86_64/fpu/printf_fphex.c: Likewise.
	* math/test-misc.c (main): Don't use union ieee854_long_double.
ports/
	* sysdeps/ia64/fpu/printf_fphex.c: Adjust for fpnum change.

3 files changed, 12 insertions, 17 deletions

diff --git a/stdio-common/printf_fp.c b/stdio-common/printf_fp.c
index e20eab6a34..2b93e6c57a 100644
--- a/stdio-common/printf_fp.c
+++ b/stdio-common/printf_fp.c
@@ -332,8 +332,7 @@ ___printf_fp (FILE *fp,
       int res;
       if (__isnanl (fpnum.ldbl))
 	{
-	  union ieee854_long_double u = { .d = fpnum.ldbl };
-	  is_neg = u.ieee.negative != 0;
+	  is_neg = signbit (fpnum.ldbl);
 	  if (isupper (info->spec))
 	    {
 	      special = "NAN";
diff --git a/stdio-common/printf_fphex.c b/stdio-common/printf_fphex.c
index 3da2eec40c..50b6fbfbc7 100644
--- a/stdio-common/printf_fphex.c
+++ b/stdio-common/printf_fphex.c
@@ -93,7 +93,7 @@ __printf_fphex (FILE *fp,
   union
     {
       union ieee754_double dbl;
-      union ieee854_long_double ldbl;
+      long double ldbl;
     }
   fpnum;
 
@@ -162,12 +162,11 @@ __printf_fphex (FILE *fp,
 #ifndef __NO_LONG_DOUBLE_MATH
   if (info->is_long_double && sizeof (long double) > sizeof (double))
     {
-      fpnum.ldbl.d = *(const long double *) args[0];
+      fpnum.ldbl = *(const long double *) args[0];
 
       /* Check for special values: not a number or infinity.  */
-      if (__isnanl (fpnum.ldbl.d))
+      if (__isnanl (fpnum.ldbl))
 	{
-	  negative = fpnum.ldbl.ieee.negative != 0;
 	  if (isupper (info->spec))
 	    {
 	      special = "NAN";
@@ -181,8 +180,7 @@ __printf_fphex (FILE *fp,
 	}
       else
 	{
-	  int res = __isinfl (fpnum.ldbl.d);
-	  if (res)
+	  if (__isinfl (fpnum.ldbl))
 	    {
 	      if (isupper (info->spec))
 		{
@@ -194,11 +192,9 @@ __printf_fphex (FILE *fp,
 		  special = "inf";
 		  wspecial = L"inf";
 		}
-	      negative = res < 0;
 	    }
-	  else
-	    negative = signbit (fpnum.ldbl.d);
 	}
+      negative = signbit (fpnum.ldbl);
     }
   else
 #endif	/* no long double */
diff --git a/stdio-common/printf_size.c b/stdio-common/printf_size.c
index 2c496e5b2f..dfb3a539b9 100644
--- a/stdio-common/printf_size.c
+++ b/stdio-common/printf_size.c
@@ -103,7 +103,7 @@ __printf_size (FILE *fp, const struct printf_info *info,
   union
     {
       union ieee754_double dbl;
-      union ieee854_long_double ldbl;
+      long double ldbl;
     }
   fpnum;
   const void *ptr = &fpnum;
@@ -123,25 +123,25 @@ __printf_size (FILE *fp, const struct printf_info *info,
 #ifndef __NO_LONG_DOUBLE_MATH
   if (info->is_long_double && sizeof (long double) > sizeof (double))
     {
-      fpnum.ldbl.d = *(const long double *) args[0];
+      fpnum.ldbl = *(const long double *) args[0];
 
       /* Check for special values: not a number or infinity.  */
-      if (__isnanl (fpnum.ldbl.d))
+      if (__isnanl (fpnum.ldbl))
 	{
 	  special = "nan";
 	  wspecial = L"nan";
 	  // fpnum_sign = 0;	Already zero
 	}
-      else if ((res = __isinfl (fpnum.ldbl.d)))
+      else if ((res = __isinfl (fpnum.ldbl)))
 	{
 	  fpnum_sign = res;
 	  special = "inf";
 	  wspecial = L"inf";
 	}
       else
-	while (fpnum.ldbl.d >= divisor && tag[1] != '\0')
+	while (fpnum.ldbl >= divisor && tag[1] != '\0')
 	  {
-	    fpnum.ldbl.d /= divisor;
+	    fpnum.ldbl /= divisor;
 	    ++tag;
 	  }
     }