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PowerPC floating point little-endian [1 of 15]


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.

	2013-07-10  Alan Modra <amodra@gmail.com>

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

diff --git a/stdio-common/printf_fp.c b/stdio-common/printf_fp.c
index e20eab6..2b93e6c 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 3da2eec..1e9c168 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 2c496e5..dfb3a53 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;
 	  }
     }
diff --git a/sysdeps/ieee754/ldbl-128ibm/printf_fphex.c b/sysdeps/ieee754/ldbl-128ibm/printf_fphex.c
index 247dc20..96e1733 100644
--- a/sysdeps/ieee754/ldbl-128ibm/printf_fphex.c
+++ b/sysdeps/ieee754/ldbl-128ibm/printf_fphex.c
@@ -27,7 +27,7 @@ do {									      \
       unsigned long long hi, lo;					      \
       int ediff;							      \
       union ibm_extended_long_double eldbl;				      \
-      eldbl.d = fpnum.ldbl.d;						      \
+      eldbl.d = fpnum.ldbl;						      \
 									      \
       assert (sizeof (long double) == 16);				      \
 									      \
diff --git a/math/test-misc.c b/math/test-misc.c
index 27d673b..f5276eb 100644
--- a/math/test-misc.c
+++ b/math/test-misc.c
@@ -722,300 +722,161 @@ main (void)
 
 #ifndef NO_LONG_DOUBLE
   {
-    union ieee854_long_double v1;
-    union ieee854_long_double v2;
-    long double ld;
+    long double v1, v2;
 
-    v1.d = ld = LDBL_MIN;
-    if (fpclassify (ld) != FP_NORMAL)
+    v1 = LDBL_MIN;
+    if (fpclassify (v1) != FP_NORMAL)
       {
-	printf ("fpclassify (LDBL_MIN) failed: %d\n", fpclassify (ld));
+	printf ("fpclassify (LDBL_MIN) failed: %d (%La)\n",
+		fpclassify (v1), v1);
 	result = 1;
       }
-    ld = nextafterl (ld, LDBL_MIN / 2.0);
-    if (fpclassify (ld) != FP_SUBNORMAL)
+    v2 = nextafterl (v1, LDBL_MIN / 2.0);
+    if (fpclassify (v2) != FP_SUBNORMAL)
       {
 	printf ("fpclassify (LDBL_MIN-epsilon) failed: %d (%La)\n",
-		fpclassify (ld), ld);
+		fpclassify (v2), v2);
 	result = 1;
       }
-    v2.d = ld = nextafterl (ld, LDBL_MIN);
-    if (fpclassify (ld) != FP_NORMAL)
+    v2 = nextafterl (v2, LDBL_MIN);
+    if (fpclassify (v2) != FP_NORMAL)
       {
 	printf ("fpclassify (LDBL_MIN-epsilon+epsilon) failed: %d (%La)\n",
-		fpclassify (ld), ld);
+		fpclassify (v2), v2);
 	result = 1;
       }
 
-    if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
+    if (v1 != v2)
       {
-	printf ("LDBL_MIN: mantissa0 differs: %8x vs %8x\n",
-		v1.ieee.mantissa0, v2.ieee.mantissa0);
-	result = 1;
-      }
-    if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
-      {
-	printf ("LDBL_MIN: mantissa1 differs: %8x vs %8x\n",
-		v1.ieee.mantissa1, v2.ieee.mantissa1);
-	result = 1;
-      }
-    if (v1.ieee.exponent != v2.ieee.exponent)
-      {
-	printf ("LDBL_MIN: exponent differs: %4x vs %4x\n",
-		v1.ieee.exponent, v2.ieee.exponent);
-	result = 1;
-      }
-    if (v1.ieee.negative != v2.ieee.negative)
-      {
-	printf ("LDBL_MIN: negative differs: %d vs %d\n",
-		v1.ieee.negative, v2.ieee.negative);
+	printf ("LDBL_MIN-epsilon+epsilon != LDBL_MIN: %La vs %La\n", v2, v1);
 	result = 1;
       }
 
-    v1.d = ld = -LDBL_MIN;
-    if (fpclassify (ld) != FP_NORMAL)
+    v1 = -LDBL_MIN;
+    if (fpclassify (v1) != FP_NORMAL)
       {
-	printf ("fpclassify (-LDBL_MIN) failed: %d\n", fpclassify (ld));
+	printf ("fpclassify (-LDBL_MIN) failed: %d (%La)\n",
+		fpclassify (v1), v1);
 	result = 1;
       }
-    ld = nextafterl (ld, -LDBL_MIN / 2.0);
-    if (fpclassify (ld) != FP_SUBNORMAL)
+    v2 = nextafterl (v1, -LDBL_MIN / 2.0);
+    if (fpclassify (v2) != FP_SUBNORMAL)
       {
 	printf ("fpclassify (-LDBL_MIN-epsilon) failed: %d (%La)\n",
-		fpclassify (ld), ld);
+		fpclassify (v2), v2);
 	result = 1;
       }
-    v2.d = ld = nextafterl (ld, -LDBL_MIN);
-    if (fpclassify (ld) != FP_NORMAL)
+    v2 = nextafterl (v2, -LDBL_MIN);
+    if (fpclassify (v2) != FP_NORMAL)
       {
 	printf ("fpclassify (-LDBL_MIN-epsilon+epsilon) failed: %d (%La)\n",
-		fpclassify (ld), ld);
+		fpclassify (v2), v2);
 	result = 1;
       }
 
-    if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
-      {
-	printf ("-LDBL_MIN: mantissa0 differs: %8x vs %8x\n",
-		v1.ieee.mantissa0, v2.ieee.mantissa0);
-	result = 1;
-      }
-    if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
-      {
-	printf ("-LDBL_MIN: mantissa1 differs: %8x vs %8x\n",
-		v1.ieee.mantissa1, v2.ieee.mantissa1);
-	result = 1;
-      }
-    if (v1.ieee.exponent != v2.ieee.exponent)
+    if (v1 != v2)
       {
-	printf ("-LDBL_MIN: exponent differs: %4x vs %4x\n",
-		v1.ieee.exponent, v2.ieee.exponent);
-	result = 1;
-      }
-    if (v1.ieee.negative != v2.ieee.negative)
-      {
-	printf ("-LDBL_MIN: negative differs: %d vs %d\n",
-		v1.ieee.negative, v2.ieee.negative);
+	printf ("-LDBL_MIN-epsilon+epsilon != -LDBL_MIN: %La vs %La\n", v2, v1);
 	result = 1;
       }
 
-    ld = LDBL_MAX;
-    if (fpclassify (ld) != FP_NORMAL)
+    v1 = LDBL_MAX;
+    if (fpclassify (v1) != FP_NORMAL)
       {
-	printf ("fpclassify (LDBL_MAX) failed: %d\n", fpclassify (ld));
+	printf ("fpclassify (LDBL_MAX) failed: %d (%La)\n",
+		fpclassify (v1), v1);
 	result = 1;
       }
-    ld = nextafterl (ld, INFINITY);
-    if (fpclassify (ld) != FP_INFINITE)
+    v2 = nextafterl (v1, INFINITY);
+    if (fpclassify (v2) != FP_INFINITE)
       {
-	printf ("fpclassify (LDBL_MAX+epsilon) failed: %d\n", fpclassify (ld));
+	printf ("fpclassify (LDBL_MAX+epsilon) failed: %d (%La)\n",
+		fpclassify (v2), v2);
 	result = 1;
       }
 
-    ld = -LDBL_MAX;
-    if (fpclassify (ld) != FP_NORMAL)
+    v1 = -LDBL_MAX;
+    if (fpclassify (v1) != FP_NORMAL)
       {
-	printf ("fpclassify (-LDBL_MAX) failed: %d\n", fpclassify (ld));
+	printf ("fpclassify (-LDBL_MAX) failed: %d (%La)\n",
+		fpclassify (v1), v1);
 	result = 1;
       }
-    ld = nextafterl (ld, -INFINITY);
-    if (fpclassify (ld) != FP_INFINITE)
+    v2 = nextafterl (v1, -INFINITY);
+    if (fpclassify (v2) != FP_INFINITE)
       {
-	printf ("fpclassify (-LDBL_MAX-epsilon) failed: %d\n",
-		fpclassify (ld));
+	printf ("fpclassify (-LDBL_MAX-epsilon) failed: %d (%La)\n",
+		fpclassify (v2), v2);
 	result = 1;
       }
 
-    v1.d = ld = 0.0625;
-    ld = nextafterl (ld, 0.0);
-    v2.d = ld = nextafterl (ld, 1.0);
+    v1 = 0.0625;
+    v2 = nextafterl (v1, 0.0);
+    v2 = nextafterl (v2, 1.0);
 
-    if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
-      {
-	printf ("0.0625L down: mantissa0 differs: %8x vs %8x\n",
-		v1.ieee.mantissa0, v2.ieee.mantissa0);
-	result = 1;
-      }
-    if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
-      {
-	printf ("0.0625L down: mantissa1 differs: %8x vs %8x\n",
-		v1.ieee.mantissa1, v2.ieee.mantissa1);
-	result = 1;
-      }
-    if (v1.ieee.exponent != v2.ieee.exponent)
-      {
-	printf ("0.0625L down: exponent differs: %4x vs %4x\n",
-		v1.ieee.exponent, v2.ieee.exponent);
-	result = 1;
-      }
-    if (v1.ieee.negative != v2.ieee.negative)
+    if (v1 != v2)
       {
-	printf ("0.0625L down: negative differs: %d vs %d\n",
-		v1.ieee.negative, v2.ieee.negative);
+	printf ("0.0625L-epsilon+epsilon != 0.0625L: %La vs %La\n", v2, v1);
 	result = 1;
       }
 
-    v1.d = ld = 0.0625;
-    ld = nextafterl (ld, 1.0);
-    v2.d = ld = nextafterl (ld, 0.0);
+    v1 = 0.0625;
+    v2 = nextafterl (v1, 1.0);
+    v2 = nextafterl (v2, 0.0);
 
-    if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
-      {
-	printf ("0.0625L up: mantissa0 differs: %8x vs %8x\n",
-		v1.ieee.mantissa0, v2.ieee.mantissa0);
-	result = 1;
-      }
-    if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
-      {
-	printf ("0.0625L up: mantissa1 differs: %8x vs %8x\n",
-		v1.ieee.mantissa1, v2.ieee.mantissa1);
-	result = 1;
-      }
-    if (v1.ieee.exponent != v2.ieee.exponent)
-      {
-	printf ("0.0625L up: exponent differs: %4x vs %4x\n",
-		v1.ieee.exponent, v2.ieee.exponent);
-	result = 1;
-      }
-    if (v1.ieee.negative != v2.ieee.negative)
+    if (v1 != v2)
       {
-	printf ("0.0625L up: negative differs: %d vs %d\n",
-		v1.ieee.negative, v2.ieee.negative);
+	printf ("0.0625L+epsilon-epsilon != 0.0625L: %La vs %La\n", v2, v1);
 	result = 1;
       }
 
-    v1.d = ld = -0.0625;
-    ld = nextafterl (ld, 0.0);
-    v2.d = ld = nextafterl (ld, -1.0);
+    v1 = -0.0625;
+    v2 = nextafterl (v1, 0.0);
+    v2 = nextafterl (v2, -1.0);
 
-    if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
+    if (v1 != v2)
       {
-	printf ("-0.0625L up: mantissa0 differs: %8x vs %8x\n",
-		v1.ieee.mantissa0, v2.ieee.mantissa0);
-	result = 1;
-      }
-    if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
-      {
-	printf ("-0.0625L up: mantissa1 differs: %8x vs %8x\n",
-		v1.ieee.mantissa1, v2.ieee.mantissa1);
-	result = 1;
-      }
-    if (v1.ieee.exponent != v2.ieee.exponent)
-      {
-	printf ("-0.0625L up: exponent differs: %4x vs %4x\n",
-		v1.ieee.exponent, v2.ieee.exponent);
-	result = 1;
-      }
-    if (v1.ieee.negative != v2.ieee.negative)
-      {
-	printf ("-0.0625L up: negative differs: %d vs %d\n",
-		v1.ieee.negative, v2.ieee.negative);
+	printf ("-0.0625L+epsilon-epsilon != -0.0625L: %La vs %La\n", v2, v1);
 	result = 1;
       }
 
-    v1.d = ld = -0.0625;
-    ld = nextafterl (ld, -1.0);
-    v2.d = ld = nextafterl (ld, 0.0);
+    v1 = -0.0625;
+    v2 = nextafterl (v1, -1.0);
+    v2 = nextafterl (v2, 0.0);
 
-    if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
-      {
-	printf ("-0.0625L down: mantissa0 differs: %8x vs %8x\n",
-		v1.ieee.mantissa0, v2.ieee.mantissa0);
-	result = 1;
-      }
-    if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
-      {
-	printf ("-0.0625L down: mantissa1 differs: %8x vs %8x\n",
-		v1.ieee.mantissa1, v2.ieee.mantissa1);
-	result = 1;
-      }
-    if (v1.ieee.exponent != v2.ieee.exponent)
+    if (v1 != v2)
       {
-	printf ("-0.0625L down: exponent differs: %4x vs %4x\n",
-		v1.ieee.exponent, v2.ieee.exponent);
-	result = 1;
-      }
-    if (v1.ieee.negative != v2.ieee.negative)
-      {
-	printf ("-0.0625L down: negative differs: %d vs %d\n",
-		v1.ieee.negative, v2.ieee.negative);
+	printf ("-0.0625L-epsilon+epsilon != -0.0625L: %La vs %La\n", v2, v1);
 	result = 1;
       }
 
-    v1.d = ld = 0.0;
-    ld = nextafterl (ld, 1.0);
-    v2.d = nextafterl (ld, -1.0);
+    v1 = 0.0;
+    v2 = nextafterl (v1, 1.0);
+    v2 = nextafterl (v2, -1.0);
 
-    if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
-      {
-	printf ("0.0L up: mantissa0 differs: %8x vs %8x\n",
-		v1.ieee.mantissa0, v2.ieee.mantissa0);
-	result = 1;
-      }
-    if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
-      {
-	printf ("0.0L up: mantissa1 differs: %8x vs %8x\n",
-		v1.ieee.mantissa1, v2.ieee.mantissa1);
-	result = 1;
-      }
-    if (v1.ieee.exponent != v2.ieee.exponent)
+    if (v1 != v2)
       {
-	printf ("0.0L up: exponent differs: %4x vs %4x\n",
-		v1.ieee.exponent, v2.ieee.exponent);
+	printf ("0.0+epsilon-epsilon != 0.0L: %La vs %La\n", v2, v1);
 	result = 1;
       }
-    if (0 != v2.ieee.negative)
+    if (signbit (v2))
       {
-	printf ("0.0L up: negative differs: 0 vs %d\n",
-		v2.ieee.negative);
+	printf ("0.0+epsilon-epsilon is negative\n");
 	result = 1;
       }
 
-    v1.d = ld = 0.0;
-    ld = nextafterl (ld, -1.0);
-    v2.d = nextafterl (ld, 1.0);
+    v1 = 0.0;
+    v2 = nextafterl (v1, -1.0);
+    v2 = nextafterl (v2, 1.0);
 
-    if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
-      {
-	printf ("0.0L down: mantissa0 differs: %8x vs %8x\n",
-		v1.ieee.mantissa0, v2.ieee.mantissa0);
-	result = 1;
-      }
-    if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
+    if (v1 != v2)
       {
-	printf ("0.0L down: mantissa1 differs: %8x vs %8x\n",
-		v1.ieee.mantissa1, v2.ieee.mantissa1);
-	result = 1;
-      }
-    if (v1.ieee.exponent != v2.ieee.exponent)
-      {
-	printf ("0.0L down: exponent differs: %4x vs %4x\n",
-		v1.ieee.exponent, v2.ieee.exponent);
+	printf ("0.0-epsilon+epsilon != 0.0L: %La vs %La\n", v2, v1);
 	result = 1;
       }
-    if (1 != v2.ieee.negative)
+    if (!signbit (v2))
       {
-	printf ("0.0L down: negative differs: 1 vs %d\n",
-		v2.ieee.negative);
+	printf ("0.0-epsilon+epsilon is positive\n");
 	result = 1;
       }
 

-- 
Alan Modra
Australia Development Lab, IBM


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