jdk8-mips64-public/hotspot: src/share/vm/ci/ciArray.cpp@edb5ab0f3fe5

8001107: @Stable annotation for constant folding of lazily evaluated variables
Reviewed-by: rbackman, twisti, kvn
Contributed-by: john.r.rose@oracle.com, vladimir.x.ivanov@oracle.com

     1 /*

     2  * Copyright (c) 1999, 2010, 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  */

    25 #include "precompiled.hpp"

    26 #include "ci/ciArray.hpp"

    27 #include "ci/ciArrayKlass.hpp"

    28 #include "ci/ciConstant.hpp"

    29 #include "ci/ciKlass.hpp"

    30 #include "ci/ciUtilities.hpp"

    31 #include "oops/objArrayOop.hpp"

    32 #include "oops/typeArrayOop.hpp"

    34 // ciArray

    35 //

    36 // This class represents an arrayOop in the HotSpot virtual

    37 // machine.

    38 static BasicType fixup_element_type(BasicType bt) {

    39   if (bt == T_ARRAY)    return T_OBJECT;

    40   if (bt == T_BOOLEAN)  return T_BYTE;

    41   return bt;

    42 }

    44 ciConstant ciArray::element_value_impl(BasicType elembt,

    45                                        arrayOop ary,

    46                                        int index) {

    47   if (ary == NULL)

    48     return ciConstant();

    49   assert(ary->is_array(), "");

    50   if (index < 0 || index >= ary->length())

    51     return ciConstant();

    52   ArrayKlass* ak = (ArrayKlass*) ary->klass();

    53   BasicType abt = ak->element_type();

    54   if (fixup_element_type(elembt) !=

    55       fixup_element_type(abt))

    56     return ciConstant();

    57   switch (elembt) {

    58   case T_ARRAY:

    59   case T_OBJECT:

    60     {

    61       assert(ary->is_objArray(), "");

    62       objArrayOop objary = (objArrayOop) ary;

    63       oop elem = objary->obj_at(index);

    64       ciEnv* env = CURRENT_ENV;

    65       ciObject* box = env->get_object(elem);

    66       return ciConstant(T_OBJECT, box);

    67     }

    68   }

    69   assert(ary->is_typeArray(), "");

    70   typeArrayOop tary = (typeArrayOop) ary;

    71   jint value = 0;

    72   switch (elembt) {

    73   case T_LONG:          return ciConstant(tary->long_at(index));

    74   case T_FLOAT:         return ciConstant(tary->float_at(index));

    75   case T_DOUBLE:        return ciConstant(tary->double_at(index));

    76   default:              return ciConstant();

    77   case T_BYTE:          value = tary->byte_at(index);           break;

    78   case T_BOOLEAN:       value = tary->byte_at(index) & 1;       break;

    79   case T_SHORT:         value = tary->short_at(index);          break;

    80   case T_CHAR:          value = tary->char_at(index);           break;

    81   case T_INT:           value = tary->int_at(index);            break;

    82   }

    83   return ciConstant(elembt, value);

    84 }

    86 // ------------------------------------------------------------------

    87 // ciArray::element_value

    88 //

    89 // Current value of an element.

    90 // Returns T_ILLEGAL if there is no element at the given index.

    91 ciConstant ciArray::element_value(int index) {

    92   BasicType elembt = element_basic_type();

    93   GUARDED_VM_ENTRY(

    94     return element_value_impl(elembt, get_arrayOop(), index);

    95   )

    96 }

    98 // ------------------------------------------------------------------

    99 // ciArray::element_value_by_offset

   100 //

   101 // Current value of an element at the specified offset.

   102 // Returns T_ILLEGAL if there is no element at the given offset.

   103 ciConstant ciArray::element_value_by_offset(intptr_t element_offset) {

   104   BasicType elembt = element_basic_type();

   105   intptr_t shift  = exact_log2(type2aelembytes(elembt));

   106   intptr_t header = arrayOopDesc::base_offset_in_bytes(elembt);

   107   intptr_t index = (element_offset - header) >> shift;

   108   intptr_t offset = header + ((intptr_t)index << shift);

   109   if (offset != element_offset || index != (jint)index)

   110     return ciConstant();

   111   return element_value((jint) index);

   112 }

   114 // ------------------------------------------------------------------

   115 // ciArray::print_impl

   116 //

   117 // Implementation of the print method.

   118 void ciArray::print_impl(outputStream* st) {

   119   st->print(" length=%d type=", length());

   120   klass()->print(st);

   121 }

Mercurial > jdk8-mips64-public > hotspot / file revision

src/share/vm/ci/ciArray.cpp@edb5ab0f3fe5

src/share/vm/ci/ciArray.cpp