1 /*
  2  * Copyright (c) 1999, 2026, Oracle and/or its affiliates. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  *
 23  */
 24 
 25 #include "ci/ciConstant.hpp"
 26 #include "ci/ciUtilities.hpp"
 27 #include "memory/allocation.hpp"
 28 #include "memory/allocation.inline.hpp"
 29 
 30 // ciConstant
 31 //
 32 // This class represents a constant value.
 33 
 34 ciConstant ciConstant::make_zero_or_null(BasicType bt) {
 35   switch (bt) {
 36   case T_FLOAT: return ciConstant((jfloat).0f);
 37   case T_DOUBLE: return ciConstant((jdouble).0);
 38   case T_LONG: return ciConstant((jlong)0L);
 39   case T_BOOLEAN:
 40   case T_CHAR:
 41   case T_BYTE:
 42   case T_SHORT:
 43   case T_INT:
 44     return ciConstant(bt, 0);
 45   case T_OBJECT:
 46   case T_ARRAY:
 47     return ciConstant(bt, CURRENT_ENV->get_object(nullptr));
 48   default:
 49     ShouldNotReachHere();
 50     return ciConstant();
 51   }
 52 }
 53 
 54 // ------------------------------------------------------------------
 55 // ciConstant::is_null_or_zero
 56 // This assumes `this->is_valid()`, otherwise, `as_object` will assert.
 57 bool ciConstant::is_null_or_zero() const {
 58   if (!is_java_primitive(basic_type())) {
 59     return as_object()->is_null_object();
 60   } else if (type2size[basic_type()] == 1) {
 61     // treat float bits as int, to avoid comparison with -0 and NaN
 62     return (_value._int == 0);
 63   } else if (type2size[basic_type()] == 2) {
 64     // treat double bits as long, to avoid comparison with -0 and NaN
 65     return (_value._long == 0);
 66   } else {
 67     return false;
 68   }
 69 }
 70 
 71 // ------------------------------------------------------------------
 72 // ciConstant::is_loaded
 73 bool ciConstant::is_loaded() const {
 74   if (is_valid()) {
 75     if (is_reference_type(basic_type())) {
 76       return as_object()->is_loaded();
 77     } else {
 78       return true;
 79     }
 80   }
 81   return false;
 82 }
 83 
 84 // ------------------------------------------------------------------
 85 // ciConstant::print
 86 void ciConstant::print() const {
 87   tty->print("<ciConstant type=%s value=",
 88              basictype_to_str(basic_type()));
 89   switch (basic_type()) {
 90   case T_BOOLEAN:
 91     tty->print("%s", bool_to_str(_value._int != 0));
 92     break;
 93   case T_CHAR:
 94   case T_BYTE:
 95   case T_SHORT:
 96   case T_INT:
 97     tty->print("%d", _value._int);
 98     break;
 99   case T_LONG:
100     tty->print(INT64_FORMAT, (int64_t)(_value._long));
101     break;
102   case T_FLOAT:
103     tty->print("%f", _value._float);
104     break;
105   case T_DOUBLE:
106     tty->print("%lf", _value._double);
107     break;
108   default:
109     if (is_reference_type(basic_type())) {
110       _value._object->print();
111     } else {
112       tty->print("ILLEGAL");
113     }
114     break;
115   }
116   tty->print(">");
117 }