@@ -1373,302 +1411,87 @@ simplify_const_unary_operation (enum rtx_code code, enum machine_mode mode,
       return CONST_DOUBLE_FROM_REAL_VALUE (d, mode);
     }
 
-  if (CONST_INT_P (op)
-      && width <= HOST_BITS_PER_WIDE_INT && width > 0)
+  if (CONST_SCALAR_INT_P (op) && width > 0)
     {
-      HOST_WIDE_INT arg0 = INTVAL (op);
-      HOST_WIDE_INT val;
+      wide_int result;
+      enum machine_mode imode = op_mode == VOIDmode ? mode : op_mode;
+      wide_int op0 = wide_int::from_rtx (op, imode);
+
+#if TARGET_SUPPORTS_WIDE_INT == 0
+      /* This assert keeps the simplification from producing a result
+	 that cannot be represented in a CONST_DOUBLE but a lot of
+	 upstream callers expect that this function never fails to
+	 simplify something and so you if you added this to the test
+	 above the code would die later anyway.  If this assert
+	 happens, you just need to make the port support wide int.  */
+      gcc_assert (width <= HOST_BITS_PER_DOUBLE_INT); 
+#endif
 
       switch (code)
 	{
 	case NOT:
-	  val = ~ arg0;
+	  result = ~op0;
 	  break;
 
 	case NEG:
-	  val = - arg0;
+	  result = op0.neg ();
 	  break;
 
 	case ABS:
-	  val = (arg0 >= 0 ? arg0 : - arg0);
+	  result = op0.abs ();
 	  break;
 
 	case FFS:
-	  arg0 &= GET_MODE_MASK (mode);
-	  val = ffs_hwi (arg0);
+	  result = op0.ffs ();
 	  break;
 
 	case CLZ:
-	  arg0 &= GET_MODE_MASK (mode);
-	  if (arg0 == 0 && CLZ_DEFINED_VALUE_AT_ZERO (mode, val))
-	    ;
-	  else
-	    val = GET_MODE_PRECISION (mode) - floor_log2 (arg0) - 1;
+	  result = op0.clz (GET_MODE_BITSIZE (mode), 
+			    GET_MODE_PRECISION (mode));
 	  break;
 
 	case CLRSB:
-	  arg0 &= GET_MODE_MASK (mode);
-	  if (arg0 == 0)
-	    val = GET_MODE_PRECISION (mode) - 1;
-	  else if (arg0 >= 0)
-	    val = GET_MODE_PRECISION (mode) - floor_log2 (arg0) - 2;
-	  else if (arg0 < 0)
-	    val = GET_MODE_PRECISION (mode) - floor_log2 (~arg0) - 2;
+	  result = op0.clrsb (GET_MODE_BITSIZE (mode), 
+			      GET_MODE_PRECISION (mode));
 	  break;
-
+	  
 	case CTZ:
-	  arg0 &= GET_MODE_MASK (mode);
-	  if (arg0 == 0)
-	    {
-	      /* Even if the value at zero is undefined, we have to come
-		 up with some replacement.  Seems good enough.  */
-	      if (! CTZ_DEFINED_VALUE_AT_ZERO (mode, val))
-		val = GET_MODE_PRECISION (mode);
-	    }
-	  else
-	    val = ctz_hwi (arg0);
+	  result = op0.ctz (GET_MODE_BITSIZE (mode), 
+			    GET_MODE_PRECISION (mode));
 	  break;
 
 	case POPCOUNT:
-	  arg0 &= GET_MODE_MASK (mode);
-	  val = 0;
-	  while (arg0)
-	    val++, arg0 &= arg0 - 1;
+	  result = op0.popcount (GET_MODE_BITSIZE (mode), 
+				 GET_MODE_PRECISION (mode));
 	  break;
 
 	case PARITY:
-	  arg0 &= GET_MODE_MASK (mode);
-	  val = 0;
-	  while (arg0)
-	    val++, arg0 &= arg0 - 1;
-	  val &= 1;
+	  result = op0.parity (GET_MODE_BITSIZE (mode), 
+			       GET_MODE_PRECISION (mode));
 	  break;
 
 	case BSWAP:
-	  {
-	    unsigned int s;
-
-	    val = 0;
-	    for (s = 0; s < width; s += 8)
-	      {
-		unsigned int d = width - s - 8;
-		unsigned HOST_WIDE_INT byte;
-		byte = (arg0 >> s) & 0xff;
-		val |= byte << d;
-	      }
-	  }
+	  result = op0.bswap ();
 	  break;
 
 	case TRUNCATE:
-	  val = arg0;
+	  result = op0.sext (mode);
 	  break;
 
 	case ZERO_EXTEND:
-	  /* When zero-extending a CONST_INT, we need to know its
-             original mode.  */
-	  gcc_assert (op_mode != VOIDmode);
-	  if (op_width == HOST_BITS_PER_WIDE_INT)
-	    {
-	      /* If we were really extending the mode,
-		 we would have to distinguish between zero-extension
-		 and sign-extension.  */
-	      gcc_assert (width == op_width);
-	      val = arg0;
-	    }
-	  else if (GET_MODE_BITSIZE (op_mode) < HOST_BITS_PER_WIDE_INT)
-	    val = arg0 & GET_MODE_MASK (op_mode);
-	  else
-	    return 0;
+	  result = op0.zext (mode);
 	  break;
 
 	case SIGN_EXTEND:
-	  if (op_mode == VOIDmode)
-	    op_mode = mode;
-	  op_width = GET_MODE_PRECISION (op_mode);
-	  if (op_width == HOST_BITS_PER_WIDE_INT)
-	    {
-	      /* If we were really extending the mode,
-		 we would have to distinguish between zero-extension
-		 and sign-extension.  */
-	      gcc_assert (width == op_width);
-	      val = arg0;
-	    }
-	  else if (op_width < HOST_BITS_PER_WIDE_INT)
-	    {
-	      val = arg0 & GET_MODE_MASK (op_mode);
-	      if (val_signbit_known_set_p (op_mode, val))
-		val |= ~GET_MODE_MASK (op_mode);
-	    }
-	  else
-	    return 0;
+	  result = op0.sext (mode);
 	  break;
 
 	case SQRT:
-	case FLOAT_EXTEND:
-	case FLOAT_TRUNCATE:
-	case SS_TRUNCATE:
-	case US_TRUNCATE:
-	case SS_NEG:
-	case US_NEG:
-	case SS_ABS:
-	  return 0;
-
-	default:
-	  gcc_unreachable ();
-	}
-
-      return gen_int_mode (val, mode);
-    }
-
-  /* We can do some operations on integer CONST_DOUBLEs.  Also allow
-     for a DImode operation on a CONST_INT.  */
-  else if (width <= HOST_BITS_PER_DOUBLE_INT
-	   && (CONST_DOUBLE_AS_INT_P (op) || CONST_INT_P (op)))
-    {
-      double_int first, value;
-
-      if (CONST_DOUBLE_AS_INT_P (op))
-	first = double_int::from_pair (CONST_DOUBLE_HIGH (op),
-				       CONST_DOUBLE_LOW (op));
-      else
-	first = double_int::from_shwi (INTVAL (op));
-
-      switch (code)
-	{
-	case NOT:
-	  value = ~first;
-	  break;
-
-	case NEG:
-	  value = -first;
-	  break;
-
-	case ABS:
-	  if (first.is_negative ())
-	    value = -first;
-	  else
-	    value = first;
-	  break;
-
-	case FFS:
-	  value.high = 0;
-	  if (first.low != 0)
-	    value.low = ffs_hwi (first.low);
-	  else if (first.high != 0)
-	    value.low = HOST_BITS_PER_WIDE_INT + ffs_hwi (first.high);
-	  else
-	    value.low = 0;
-	  break;
-
-	case CLZ:
-	  value.high = 0;
-	  if (first.high != 0)
-	    value.low = GET_MODE_PRECISION (mode) - floor_log2 (first.high) - 1
-	              - HOST_BITS_PER_WIDE_INT;
-	  else if (first.low != 0)
-	    value.low = GET_MODE_PRECISION (mode) - floor_log2 (first.low) - 1;
-	  else if (! CLZ_DEFINED_VALUE_AT_ZERO (mode, value.low))
-	    value.low = GET_MODE_PRECISION (mode);
-	  break;
-
-	case CTZ:
-	  value.high = 0;
-	  if (first.low != 0)
-	    value.low = ctz_hwi (first.low);
-	  else if (first.high != 0)
-	    value.low = HOST_BITS_PER_WIDE_INT + ctz_hwi (first.high);
-	  else if (! CTZ_DEFINED_VALUE_AT_ZERO (mode, value.low))
-	    value.low = GET_MODE_PRECISION (mode);
-	  break;
-
-	case POPCOUNT:
-	  value = double_int_zero;
-	  while (first.low)
-	    {
-	      value.low++;
-	      first.low &= first.low - 1;
-	    }
-	  while (first.high)
-	    {
-	      value.low++;
-	      first.high &= first.high - 1;
-	    }
-	  break;
-
-	case PARITY:
-	  value = double_int_zero;
-	  while (first.low)
-	    {
-	      value.low++;
-	      first.low &= first.low - 1;
-	    }
-	  while (first.high)
-	    {
-	      value.low++;
-	      first.high &= first.high - 1;
-	    }
-	  value.low &= 1;
-	  break;
-
-	case BSWAP:
-	  {
-	    unsigned int s;
-
-	    value = double_int_zero;
-	    for (s = 0; s < width; s += 8)
-	      {
-		unsigned int d = width - s - 8;
-		unsigned HOST_WIDE_INT byte;
-
-		if (s < HOST_BITS_PER_WIDE_INT)
-		  byte = (first.low >> s) & 0xff;
-		else
-		  byte = (first.high >> (s - HOST_BITS_PER_WIDE_INT)) & 0xff;
-
-		if (d < HOST_BITS_PER_WIDE_INT)
-		  value.low |= byte << d;
-		else
-		  value.high |= byte << (d - HOST_BITS_PER_WIDE_INT);
-	      }
-	  }
-	  break;
-
-	case TRUNCATE:
-	  /* This is just a change-of-mode, so do nothing.  */
-	  value = first;
-	  break;
-
-	case ZERO_EXTEND:
-	  gcc_assert (op_mode != VOIDmode);
-
-	  if (op_width > HOST_BITS_PER_WIDE_INT)
-	    return 0;
-
-	  value = double_int::from_uhwi (first.low & GET_MODE_MASK (op_mode));
-	  break;
-
-	case SIGN_EXTEND:
-	  if (op_mode == VOIDmode
-	      || op_width > HOST_BITS_PER_WIDE_INT)
-	    return 0;
-	  else
-	    {
-	      value.low = first.low & GET_MODE_MASK (op_mode);
-	      if (val_signbit_known_set_p (op_mode, value.low))
-		value.low |= ~GET_MODE_MASK (op_mode);
-
-	      value.high = HWI_SIGN_EXTEND (value.low);
-	    }
-	  break;
-
-	case SQRT:
-	  return 0;
-
 	default:
 	  return 0;
 	}
 
-      return immed_double_int_const (value, mode);
+      return immed_wide_int_const (result, mode);
     }