(e64toe): Properly distinguish between NaN and infinity bit patterns for real-words...

(e64toe): Properly distinguish between NaN and infinity bit patterns
for real-words-big-endian targets.
(endian): Add two explicit casts.
(e64toe): Support ARM extended precision fp format.  Check negative
infinities properly for NaNs.
(toe64): Support ARM extended precision fp format.

From-SVN: r11688

diff --git a/gcc/real.c b/gcc/real.c
index ec443706aa3e9a106f4385397b85baab64845e92..e8f78ad73cfb296f6cd9de6eca989a51c76e524b 100644 (file)
--- a/gcc/real.c
+++ b/gcc/real.c
@@ -471,7 +471,7 @@ endian (e, x, mode)
          th = (unsigned long) e[0] & 0xffff;
          t = (unsigned long) e[1] & 0xffff;
          t |= th << 16;
-         x[0] = t;
+         x[0] = (long) t;
          break;
 
        default:
@@ -520,7 +520,7 @@ endian (e, x, mode)
          th = (unsigned long) e[1] & 0xffff;
          t = (unsigned long) e[0] & 0xffff;
          t |= th << 16;
-         x[0] = t;
+         x[0] = (long) t;
          break;
 
        default:
@@ -2978,8 +2978,14 @@ e64toe (pe, y)
   else
     {
       p = &yy[0] + (NE - 1);
+#ifdef ARM_EXTENDED_IEEE_FORMAT
+      /* For ARMs, the exponent is in the lowest 15 bits of the word.  */
+      *p-- = (e[0] & 0x8000) | (e[1] & 0x7ffff);
+      e += 2;
+#else
       *p-- = *e++;
       ++e;
+#endif
       for (i = 0; i < 4; i++)
        *p-- = *e++;
     }
@@ -2987,7 +2993,7 @@ e64toe (pe, y)
 #ifdef INFINITY
   /* Point to the exponent field and check max exponent cases.  */
   p = &yy[NE - 1];
-  if (*p == 0x7fff)
+  if ((*p & 0x7fff) == 0x7fff)
     {
 #ifdef NANS
       if (! REAL_WORDS_BIG_ENDIAN)
@@ -3005,7 +3011,8 @@ e64toe (pe, y)
        }
       else
        {
-         for (i = 1; i <= 4; i++)
+#ifdef ARM_EXTENDED_IEEE_FORMAT
+         for (i = 2; i <= 5; i++)
            {
              if (pe[i] != 0)
                {
@@ -3013,6 +3020,23 @@ e64toe (pe, y)
                  return;
                }
            }
+#else /* not ARM */
+         /* In Motorola extended precision format, the most significant
+            bit of an infinity mantissa could be either 1 or 0.  It is
+            the lower order bits that tell whether the value is a NaN.  */
+         if ((pe[2] & 0x7fff) != 0)
+           goto bigend_nan;
+
+         for (i = 3; i <= 5; i++)
+           {
+             if (pe[i] != 0)
+               {
+bigend_nan:
+                 enan (y, (*p & 0x8000) != 0);
+                 return;
+               }
+           }
+#endif /* not ARM */
        }
 #endif /* NANS */
       eclear (y);
@@ -3390,11 +3414,17 @@ toe64 (a, b)
 #ifdef IEEE
   if (REAL_WORDS_BIG_ENDIAN)
     {
+#ifdef ARM_EXTENDED_IEEE_FORMAT
+      /* The exponent is in the lowest 15 bits of the first word.  */
+      *q++ = i ? 0x8000 : 0;
+      *q++ = *p++;
+#else
       if (i)
        *q++ = *p++ | 0x8000;
       else
        *q++ = *p++;
       *q++ = 0;
+#endif
     }
   else
     {