1 /*
   2  * Copyright (c) 1997, 2018, 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 "precompiled.hpp"
  26 #include "classfile/systemDictionary.hpp"
  27 #include "memory/oopFactory.hpp"
  28 #include "memory/resourceArea.hpp"
  29 #include "oops/oop.inline.hpp"
  30 #include "oops/typeArrayKlass.hpp"
  31 #include "runtime/fieldType.hpp"
  32 #include "runtime/signature.hpp"
  33 
  34 BasicType FieldType::basic_type(Symbol* signature) {
  35   return char2type(signature->char_at(0));
  36 }
  37 
  38 // Check if it is a valid array signature
  39 bool FieldType::is_valid_array_signature(Symbol* sig) {
  40   assert(sig->utf8_length() > 1, "this should already have been checked");
  41   assert(sig->char_at(0) == '[', "this should already have been checked");
  42   // The first character is already checked
  43   int i = 1;
  44   int len = sig->utf8_length();
  45   // First skip all '['s
  46   while(i < len - 1 && sig->char_at(i) == '[') i++;
  47 
  48   // Check type
  49   switch(sig->char_at(i)) {
  50     case 'B': // T_BYTE
  51     case 'C': // T_CHAR
  52     case 'D': // T_DOUBLE
  53     case 'F': // T_FLOAT
  54     case 'I': // T_INT
  55     case 'J': // T_LONG
  56     case 'S': // T_SHORT
  57     case 'Z': // T_BOOLEAN
  58       // If it is an array, the type is the last character
  59       return (i + 1 == len);
  60     case 'Q': // fall through
  61     case 'L':
  62       // If it is a class name, the last character must be a ';'
  63       return sig->char_at(len - 1) == ';';
  64   }
  65 
  66   return false;
  67 }
  68 
  69 BasicType FieldType::get_array_info(Symbol* signature, FieldArrayInfo& fd, TRAPS) {
  70   assert(basic_type(signature) == T_ARRAY, "must be array");
  71   int index = 1;
  72   int dim   = 1;
  73   while (signature->char_at(index) == '[') {
  74     index++;
  75     dim++;
  76   }
  77   ResourceMark rm;
  78   char *element = signature->as_C_string() + index;
  79   BasicType element_type = char2type(element[0]);
  80   if (element_type == T_OBJECT || element_type == T_VALUETYPE) {
  81     int len = (int)strlen(element);
  82     assert(element[len-1] == ';', "last char should be a semicolon");
  83     element[len-1] = '\0';        // chop off semicolon
  84     fd._object_key = SymbolTable::new_symbol(element + 1, CHECK_(T_BYTE));
  85   }
  86   // Pass dimension back to caller
  87   fd._dimension = dim;
  88   fd._storage_props = get_array_storage_properties(signature);
  89   return element_type;
  90 }
  91 
  92 ArrayStorageProperties FieldType::get_array_storage_properties(Symbol* signature) {
  93   return (signature->is_Q_array_signature() || signature->is_Q_signature()) ? ArrayStorageProperties::flattened_and_null_free : ArrayStorageProperties::empty;
  94 }