real.c (do_fix_trunc): New.

        * real.c (do_fix_trunc): New.
        (real_arithmetic): Call it.
        * simplify-rtx.c (simplify_unary_operation): Handle FIX
        with a floating-point result mode.

From-SVN: r57223

gcc/ChangeLog

 2002-09-16  Richard Henderson  <rth@redhat.com>
 
+	* real.c (do_fix_trunc): New.
+	(real_arithmetic): Call it.
+	* simplify-rtx.c (simplify_unary_operation): Handle FIX
+	with a floating-point result mode.
+
+2002-09-16  Richard Henderson  <rth@redhat.com>
+
 	* builtin-types.def (BT_FN_FLOAT_CONST_STRING): New.
 	(BT_FN_DOUBLE_CONST_STRING, BT_FN_LONG_DOUBLE_CONST_STRING): New.
 	* builtins.def (__builtin_nan, __builtin_nanf, __builtin_nanl): New.

gcc/real.c

@@ -174,6 +174,8 @@ static void do_divide PARAMS ((struct real_value *, const struct real_value *,
 			       const struct real_value *));
 static int do_compare PARAMS ((const struct real_value *,
 			       const struct real_value *, int));
+static void do_fix_trunc PARAMS ((struct real_value *,
+				  const struct real_value *));
 
 static const struct real_value * ten_to_ptwo PARAMS ((int));
 static const struct real_value * real_digit PARAMS ((int));
@@ -1013,6 +1015,34 @@ do_compare (a, b, nan_result)
   return (a->sign ? -ret : ret);
 }
 
+/* Return A truncated to an integral value toward zero.  */
+
+void
+do_fix_trunc (r, a)
+     struct real_value *r;
+     const struct real_value *a;
+{
+  *r = *a;
+
+  switch (a->class)
+    {
+    case rvc_zero:
+    case rvc_inf:
+    case rvc_nan:
+      break;
+
+    case rvc_normal:
+      if (r->exp <= 0)
+	get_zero (r, r->sign);
+      else if (r->exp < SIGNIFICAND_BITS)
+	clear_significand_below (r, SIGNIFICAND_BITS - r->exp);
+      break;
+
+    default:
+      abort ();
+    }
+}
+
 /* Perform the binary or unary operation described by CODE.
    For a unary operation, leave OP1 NULL.  */
 
@@ -1073,6 +1103,10 @@ real_arithmetic (tr, icode, top0, top1)
       r->sign = 0;
       break;
 
+    case FIX_TRUNC_EXPR:
+      do_fix_trunc (r, op0);
+      break;
+
     default:
       abort ();
     }

gcc/simplify-rtx.c

@@ -599,10 +599,22 @@ simplify_unary_operation (code, mode, op, op_mode)
 	  /* We don't attempt to optimize this.  */
 	  return 0;
 
-	case ABS:	      d = REAL_VALUE_ABS (d);			break;
-	case NEG:	      d = REAL_VALUE_NEGATE (d);		break;
-	case FLOAT_TRUNCATE:  d = real_value_truncate (mode, d);	break;
-	case FLOAT_EXTEND:    /* All this does is change the mode.  */  break;
+	case ABS:
+	  d = REAL_VALUE_ABS (d);
+	  break;
+	case NEG:
+	  d = REAL_VALUE_NEGATE (d);
+	  break;
+	case FLOAT_TRUNCATE:
+	  d = real_value_truncate (mode, d);
+	  break;
+	case FLOAT_EXTEND:
+	  /* All this does is change the mode.  */
+	  break;
+	case FIX:
+	  real_arithmetic (&d, FIX_TRUNC_EXPR, &d, NULL);
+	  break;
+
 	default:
 	  abort ();
 	}