jdk8-mips64-public/hotspot: src/share/vm/classfile/verificationType.hpp@01522ca68fc7

8015237: Parallelize string table scanning during strong root processing
Summary: Parallelize the scanning of the intern string table by having each GC worker claim a given number of buckets. Changes were also reviewed by Per Liden <per.liden@oracle.com>.
Reviewed-by: tschatzl, stefank, twisti

     1 /*

     2  * Copyright (c) 2003, 2012, 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 #ifndef SHARE_VM_CLASSFILE_VERIFICATIONTYPE_HPP

    26 #define SHARE_VM_CLASSFILE_VERIFICATIONTYPE_HPP

    28 #include "classfile/systemDictionary.hpp"

    29 #include "memory/allocation.hpp"

    30 #include "oops/instanceKlass.hpp"

    31 #include "oops/oop.inline.hpp"

    32 #include "oops/symbol.hpp"

    33 #include "runtime/handles.hpp"

    34 #include "runtime/signature.hpp"

    36 enum {

    37   // As specifed in the JVM spec

    38   ITEM_Top = 0,

    39   ITEM_Integer = 1,

    40   ITEM_Float = 2,

    41   ITEM_Double = 3,

    42   ITEM_Long = 4,

    43   ITEM_Null = 5,

    44   ITEM_UninitializedThis = 6,

    45   ITEM_Object = 7,

    46   ITEM_Uninitialized = 8,

    47   ITEM_Bogus = (uint)-1

    48 };

    50 class ClassVerifier;

    52 class VerificationType VALUE_OBJ_CLASS_SPEC {

    53   private:

    54     // Least significant bits of _handle are always 0, so we use these as

    55     // the indicator that the _handle is valid.  Otherwise, the _data field

    56     // contains encoded data (as specified below).  Should the VM change

    57     // and the lower bits on oops aren't 0, the assert in the constructor

    58     // will catch this and we'll have to add a descriminator tag to this

    59     // structure.

    60     union {

    61       Symbol*   _sym;

    62       uintptr_t _data;

    63     } _u;

    65     enum {

    66       // These rest are not found in classfiles, but used by the verifier

    67       ITEM_Boolean = 9, ITEM_Byte, ITEM_Short, ITEM_Char,

    68       ITEM_Long_2nd, ITEM_Double_2nd

    69     };

    71     // Enum for the _data field

    72     enum {

    73       // Bottom two bits determine if the type is a reference, primitive,

    74       // uninitialized or a query-type.

    75       TypeMask           = 0x00000003,

    77       // Topmost types encoding

    78       Reference          = 0x0,        // _sym contains the name

    79       Primitive          = 0x1,        // see below for primitive list

    80       Uninitialized      = 0x2,        // 0x00ffff00 contains bci

    81       TypeQuery          = 0x3,        // Meta-types used for category testing

    83       // Utility flags

    84       ReferenceFlag      = 0x00,       // For reference query types

    85       Category1Flag      = 0x01,       // One-word values

    86       Category2Flag      = 0x02,       // First word of a two-word value

    87       Category2_2ndFlag  = 0x04,       // Second word of a two-word value

    89       // special reference values

    90       Null               = 0x00000000, // A reference with a 0 sym is null

    92       // Primitives categories (the second byte determines the category)

    93       Category1          = (Category1Flag     << 1 * BitsPerByte) | Primitive,

    94       Category2          = (Category2Flag     << 1 * BitsPerByte) | Primitive,

    95       Category2_2nd      = (Category2_2ndFlag << 1 * BitsPerByte) | Primitive,

    97       // Primitive values (type descriminator stored in most-signifcant bytes)

    98       Bogus              = (ITEM_Bogus      << 2 * BitsPerByte) | Category1,

    99       Boolean            = (ITEM_Boolean    << 2 * BitsPerByte) | Category1,

   100       Byte               = (ITEM_Byte       << 2 * BitsPerByte) | Category1,

   101       Short              = (ITEM_Short      << 2 * BitsPerByte) | Category1,

   102       Char               = (ITEM_Char       << 2 * BitsPerByte) | Category1,

   103       Integer            = (ITEM_Integer    << 2 * BitsPerByte) | Category1,

   104       Float              = (ITEM_Float      << 2 * BitsPerByte) | Category1,

   105       Long               = (ITEM_Long       << 2 * BitsPerByte) | Category2,

   106       Double             = (ITEM_Double     << 2 * BitsPerByte) | Category2,

   107       Long_2nd           = (ITEM_Long_2nd   << 2 * BitsPerByte) | Category2_2nd,

   108       Double_2nd         = (ITEM_Double_2nd << 2 * BitsPerByte) | Category2_2nd,

   110       // Used by Uninitialized (second and third bytes hold the bci)

   111       BciMask            = 0xffff << 1 * BitsPerByte,

   112       BciForThis         = ((u2)-1),   // A bci of -1 is an Unintialized-This

   114       // Query values

   115       ReferenceQuery     = (ReferenceFlag     << 1 * BitsPerByte) | TypeQuery,

   116       Category1Query     = (Category1Flag     << 1 * BitsPerByte) | TypeQuery,

   117       Category2Query     = (Category2Flag     << 1 * BitsPerByte) | TypeQuery,

   118       Category2_2ndQuery = (Category2_2ndFlag << 1 * BitsPerByte) | TypeQuery

   119     };

   121   VerificationType(uintptr_t raw_data) {

   122     _u._data = raw_data;

   123   }

   125  public:

   127   VerificationType() { *this = bogus_type(); }

   129   // Create verification types

   130   static VerificationType bogus_type() { return VerificationType(Bogus); }

   131   static VerificationType top_type() { return bogus_type(); } // alias

   132   static VerificationType null_type() { return VerificationType(Null); }

   133   static VerificationType integer_type() { return VerificationType(Integer); }

   134   static VerificationType float_type() { return VerificationType(Float); }

   135   static VerificationType long_type() { return VerificationType(Long); }

   136   static VerificationType long2_type() { return VerificationType(Long_2nd); }

   137   static VerificationType double_type() { return VerificationType(Double); }

   138   static VerificationType boolean_type() { return VerificationType(Boolean); }

   139   static VerificationType byte_type() { return VerificationType(Byte); }

   140   static VerificationType char_type() { return VerificationType(Char); }

   141   static VerificationType short_type() { return VerificationType(Short); }

   142   static VerificationType double2_type()

   143     { return VerificationType(Double_2nd); }

   145   // "check" types are used for queries.  A "check" type is not assignable

   146   // to anything, but the specified types are assignable to a "check".  For

   147   // example, any category1 primitive is assignable to category1_check and

   148   // any reference is assignable to reference_check.

   149   static VerificationType reference_check()

   150     { return VerificationType(ReferenceQuery); }

   151   static VerificationType category1_check()

   152     { return VerificationType(Category1Query); }

   153   static VerificationType category2_check()

   154     { return VerificationType(Category2Query); }

   155   static VerificationType category2_2nd_check()

   156     { return VerificationType(Category2_2ndQuery); }

   158   // For reference types, store the actual Symbol

   159   static VerificationType reference_type(Symbol* sh) {

   160       assert(((uintptr_t)sh & 0x3) == 0, "Symbols must be aligned");

   161       // If the above assert fails in the future because oop* isn't aligned,

   162       // then this type encoding system will have to change to have a tag value

   163       // to descriminate between oops and primitives.

   164       return VerificationType((uintptr_t)sh);

   165   }

   166   static VerificationType uninitialized_type(u2 bci)

   167     { return VerificationType(bci << 1 * BitsPerByte | Uninitialized); }

   168   static VerificationType uninitialized_this_type()

   169     { return uninitialized_type(BciForThis); }

   171   // Create based on u1 read from classfile

   172   static VerificationType from_tag(u1 tag);

   174   bool is_bogus() const     { return (_u._data == Bogus); }

   175   bool is_null() const      { return (_u._data == Null); }

   176   bool is_boolean() const   { return (_u._data == Boolean); }

   177   bool is_byte() const      { return (_u._data == Byte); }

   178   bool is_char() const      { return (_u._data == Char); }

   179   bool is_short() const     { return (_u._data == Short); }

   180   bool is_integer() const   { return (_u._data == Integer); }

   181   bool is_long() const      { return (_u._data == Long); }

   182   bool is_float() const     { return (_u._data == Float); }

   183   bool is_double() const    { return (_u._data == Double); }

   184   bool is_long2() const     { return (_u._data == Long_2nd); }

   185   bool is_double2() const   { return (_u._data == Double_2nd); }

   186   bool is_reference() const { return ((_u._data & TypeMask) == Reference); }

   187   bool is_category1() const {

   188     // This should return true for all one-word types, which are category1

   189     // primitives, and references (including uninitialized refs).  Though

   190     // the 'query' types should technically return 'false' here, if we

   191     // allow this to return true, we can perform the test using only

   192     // 2 operations rather than 8 (3 masks, 3 compares and 2 logical 'ands').

   193     // Since noone should call this on a query type anyway, this is ok.

   194     assert(!is_check(), "Must not be a check type (wrong value returned)");

   195     return ((_u._data & Category1) != Primitive);

   196     // should only return false if it's a primitive, and the category1 flag

   197     // is not set.

   198   }

   199   bool is_category2() const { return ((_u._data & Category2) == Category2); }

   200   bool is_category2_2nd() const {

   201     return ((_u._data & Category2_2nd) == Category2_2nd);

   202   }

   203   bool is_reference_check() const { return _u._data == ReferenceQuery; }

   204   bool is_category1_check() const { return _u._data == Category1Query; }

   205   bool is_category2_check() const { return _u._data == Category2Query; }

   206   bool is_category2_2nd_check() const { return _u._data == Category2_2ndQuery; }

   207   bool is_check() const { return (_u._data & TypeQuery) == TypeQuery; }

   209   bool is_x_array(char sig) const {

   210     return is_null() || (is_array() && (name()->byte_at(1) == sig));

   211   }

   212   bool is_int_array() const { return is_x_array('I'); }

   213   bool is_byte_array() const { return is_x_array('B'); }

   214   bool is_bool_array() const { return is_x_array('Z'); }

   215   bool is_char_array() const { return is_x_array('C'); }

   216   bool is_short_array() const { return is_x_array('S'); }

   217   bool is_long_array() const { return is_x_array('J'); }

   218   bool is_float_array() const { return is_x_array('F'); }

   219   bool is_double_array() const { return is_x_array('D'); }

   220   bool is_object_array() const { return is_x_array('L'); }

   221   bool is_array_array() const { return is_x_array('['); }

   222   bool is_reference_array() const

   223     { return is_object_array() || is_array_array(); }

   224   bool is_object() const

   225     { return (is_reference() && !is_null() && name()->utf8_length() >= 1 &&

   226               name()->byte_at(0) != '['); }

   227   bool is_array() const

   228     { return (is_reference() && !is_null() && name()->utf8_length() >= 2 &&

   229               name()->byte_at(0) == '['); }

   230   bool is_uninitialized() const

   231     { return ((_u._data & Uninitialized) == Uninitialized); }

   232   bool is_uninitialized_this() const

   233     { return is_uninitialized() && bci() == BciForThis; }

   235   VerificationType to_category2_2nd() const {

   236     assert(is_category2(), "Must be a double word");

   237     return VerificationType(is_long() ? Long_2nd : Double_2nd);

   238   }

   240   u2 bci() const {

   241     assert(is_uninitialized(), "Must be uninitialized type");

   242     return ((_u._data & BciMask) >> 1 * BitsPerByte);

   243   }

   245   Symbol* name() const {

   246     assert(is_reference() && !is_null(), "Must be a non-null reference");

   247     return _u._sym;

   248   }

   250   bool equals(const VerificationType& t) const {

   251     return (_u._data == t._u._data ||

   252       (is_reference() && t.is_reference() && !is_null() && !t.is_null() &&

   253        name() == t.name()));

   254   }

   256   bool operator ==(const VerificationType& t) const {

   257     return equals(t);

   258   }

   260   bool operator !=(const VerificationType& t) const {

   261     return !equals(t);

   262   }

   264   // The whole point of this type system - check to see if one type

   265   // is assignable to another.  Returns true if one can assign 'from' to

   266   // this.

   267   bool is_assignable_from(

   268       const VerificationType& from, ClassVerifier* context, TRAPS) const {

   269     if (equals(from) || is_bogus()) {

   270       return true;

   271     } else {

   272       switch(_u._data) {

   273         case Category1Query:

   274           return from.is_category1();

   275         case Category2Query:

   276           return from.is_category2();

   277         case Category2_2ndQuery:

   278           return from.is_category2_2nd();

   279         case ReferenceQuery:

   280           return from.is_reference() || from.is_uninitialized();

   281         case Boolean:

   282         case Byte:

   283         case Char:

   284         case Short:

   285           // An int can be assigned to boolean, byte, char or short values.

   286           return from.is_integer();

   287         default:

   288           if (is_reference() && from.is_reference()) {

   289             return is_reference_assignable_from(from, context, CHECK_false);

   290           } else {

   291             return false;

   292           }

   293       }

   294     }

   295   }

   297   VerificationType get_component(ClassVerifier* context, TRAPS) const;

   299   int dimensions() const {

   300     assert(is_array(), "Must be an array");

   301     int index = 0;

   302     while (name()->byte_at(index++) == '[');

   303     return index;

   304   }

   306   void print_on(outputStream* st) const;

   308  private:

   310   bool is_reference_assignable_from(

   311     const VerificationType&, ClassVerifier*, TRAPS) const;

   312 };

   314 #endif // SHARE_VM_CLASSFILE_VERIFICATIONTYPE_HPP

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

src/share/vm/classfile/verificationType.hpp@01522ca68fc7

src/share/vm/classfile/verificationType.hpp