src/share/vm/code/exceptionHandlerTable.cpp

Wed, 02 Jun 2010 22:45:42 -0700

author
jrose
date
Wed, 02 Jun 2010 22:45:42 -0700
changeset 1934
e9ff18c4ace7
parent 1907
c18cbe5936b8
child 2103
3e8fbc61cee8
permissions
-rw-r--r--

Merge

     1 /*
     2  * Copyright (c) 1998, 2005, 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 "incls/_precompiled.incl"
    26 #include "incls/_exceptionHandlerTable.cpp.incl"
    28 void ExceptionHandlerTable::add_entry(HandlerTableEntry entry) {
    29   _nesting.check();
    30   if (_length >= _size) {
    31     // not enough space => grow the table (amortized growth, double its size)
    32     guarantee(_size > 0, "no space allocated => cannot grow the table since it is part of nmethod");
    33     int new_size = _size * 2;
    34     _table = REALLOC_RESOURCE_ARRAY(HandlerTableEntry, _table, _size, new_size);
    35     _size = new_size;
    36   }
    37   assert(_length < _size, "sanity check");
    38   _table[_length++] = entry;
    39 }
    42 HandlerTableEntry* ExceptionHandlerTable::subtable_for(int catch_pco) const {
    43   int i = 0;
    44   while (i < _length) {
    45     HandlerTableEntry* t = _table + i;
    46     if (t->pco() == catch_pco) {
    47       // found subtable matching the catch_pco
    48       return t;
    49     } else {
    50       // advance to next subtable
    51       i += t->len() + 1; // +1 for header
    52     }
    53   }
    54   return NULL;
    55 }
    58 ExceptionHandlerTable::ExceptionHandlerTable(int initial_size) {
    59   guarantee(initial_size > 0, "initial size must be > 0");
    60   _table  = NEW_RESOURCE_ARRAY(HandlerTableEntry, initial_size);
    61   _length = 0;
    62   _size   = initial_size;
    63 }
    66 ExceptionHandlerTable::ExceptionHandlerTable(const nmethod* nm) {
    67   _table  = (HandlerTableEntry*)nm->handler_table_begin();
    68   _length = nm->handler_table_size() / sizeof(HandlerTableEntry);
    69   _size   = 0; // no space allocated by ExeptionHandlerTable!
    70 }
    73 void ExceptionHandlerTable::add_subtable(
    74   int                 catch_pco,
    75   GrowableArray<intptr_t>* handler_bcis,
    76   GrowableArray<intptr_t>* scope_depths_from_top_scope,
    77   GrowableArray<intptr_t>* handler_pcos
    78 ) {
    79   assert(subtable_for(catch_pco) == NULL, "catch handlers for this catch_pco added twice");
    80   assert(handler_bcis->length() == handler_pcos->length(), "bci & pc table have different length");
    81   assert(scope_depths_from_top_scope == NULL || handler_bcis->length() == scope_depths_from_top_scope->length(), "bci & scope_depths table have different length");
    82   if (handler_bcis->length() > 0) {
    83     // add subtable header
    84     add_entry(HandlerTableEntry(handler_bcis->length(), catch_pco, 0));
    85     // add individual entries
    86     for (int i = 0; i < handler_bcis->length(); i++) {
    87       intptr_t scope_depth = 0;
    88       if (scope_depths_from_top_scope != NULL) {
    89         scope_depth = scope_depths_from_top_scope->at(i);
    90       }
    91       add_entry(HandlerTableEntry(handler_bcis->at(i), handler_pcos->at(i), scope_depth));
    92       assert(entry_for(catch_pco, handler_bcis->at(i), scope_depth)->pco() == handler_pcos->at(i), "entry not added correctly (1)");
    93       assert(entry_for(catch_pco, handler_bcis->at(i), scope_depth)->scope_depth() == scope_depth, "entry not added correctly (2)");
    94     }
    95   }
    96 }
    99 void ExceptionHandlerTable::copy_to(nmethod* nm) {
   100   assert(size_in_bytes() == nm->handler_table_size(), "size of space allocated in nmethod incorrect");
   101   memmove(nm->handler_table_begin(), _table, size_in_bytes());
   102 }
   105 HandlerTableEntry* ExceptionHandlerTable::entry_for(int catch_pco, int handler_bci, int scope_depth) const {
   106   HandlerTableEntry* t = subtable_for(catch_pco);
   107   if (t != NULL) {
   108     int l = t->len();
   109     while (l-- > 0) {
   110       t++;
   111       if (t->bci() == handler_bci && t->scope_depth() == scope_depth) return t;
   112     }
   113   }
   114   return NULL;
   115 }
   118 void ExceptionHandlerTable::print_subtable(HandlerTableEntry* t) const {
   119   int l = t->len();
   120   tty->print_cr("catch_pco = %d (%d entries)", t->pco(), l);
   121   while (l-- > 0) {
   122     t++;
   123     tty->print_cr("  bci %d at scope depth %d -> pco %d", t->bci(), t->scope_depth(), t->pco());
   124   }
   125 }
   128 void ExceptionHandlerTable::print() const {
   129   tty->print_cr("ExceptionHandlerTable (size = %d bytes)", size_in_bytes());
   130   int i = 0;
   131   while (i < _length) {
   132     HandlerTableEntry* t = _table + i;
   133     print_subtable(t);
   134     // advance to next subtable
   135     i += t->len() + 1; // +1 for header
   136   }
   137 }
   139 void ExceptionHandlerTable::print_subtable_for(int catch_pco) const {
   140   HandlerTableEntry* subtable = subtable_for(catch_pco);
   142   if( subtable != NULL ) { print_subtable( subtable ); }
   143 }
   145 // ----------------------------------------------------------------------------
   146 // Implicit null exception tables.  Maps an exception PC offset to a
   147 // continuation PC offset.  During construction it's a variable sized
   148 // array with a max size and current length.  When stored inside an
   149 // nmethod a zero length table takes no space.  This is detected by
   150 // nul_chk_table_size() == 0.  Otherwise the table has a length word
   151 // followed by pairs of <excp-offset, const-offset>.
   152 void ImplicitExceptionTable::set_size( uint size ) {
   153   _size = size;
   154   _data = NEW_RESOURCE_ARRAY(implicit_null_entry, (size*2));
   155   _len = 0;
   156 }
   158 void ImplicitExceptionTable::append( uint exec_off, uint cont_off ) {
   159   assert( (sizeof(implicit_null_entry) >= 4) || (exec_off < 65535), "" );
   160   assert( (sizeof(implicit_null_entry) >= 4) || (cont_off < 65535), "" );
   161   uint l = len();
   162   if (l == _size) {
   163     uint old_size_in_elements = _size*2;
   164     if (_size == 0) _size = 4;
   165     _size *= 2;
   166     uint new_size_in_elements = _size*2;
   167     _data = REALLOC_RESOURCE_ARRAY(uint, _data, old_size_in_elements, new_size_in_elements);
   168   }
   169   *(adr(l)  ) = exec_off;
   170   *(adr(l)+1) = cont_off;
   171   _len = l+1;
   172 };
   174 uint ImplicitExceptionTable::at( uint exec_off ) const {
   175   uint l = len();
   176   for( uint i=0; i<l; i++ )
   177     if( *adr(i) == exec_off )
   178       return *(adr(i)+1);
   179   return 0;                     // Failed to find any execption offset
   180 }
   182 void ImplicitExceptionTable::print(address base) const {
   183   tty->print("{");
   184   for( uint i=0; i<len(); i++ )
   185     tty->print("< "INTPTR_FORMAT", "INTPTR_FORMAT" > ",base + *adr(i), base + *(adr(i)+1));
   186   tty->print_cr("}");
   187 }
   189 ImplicitExceptionTable::ImplicitExceptionTable(const nmethod* nm) {
   190   if (nm->nul_chk_table_size() == 0) {
   191     _len = 0;
   192     _data = NULL;
   193   } else {
   194     // the first word is the length if non-zero, so read it out and
   195     // skip to the next word to get the table.
   196     _data  = (implicit_null_entry*)nm->nul_chk_table_begin();
   197     _len = _data[0];
   198     _data++;
   199   }
   200   _size = len();
   201   assert(size_in_bytes() <= nm->nul_chk_table_size(), "size of space allocated in nmethod incorrect");
   202 }
   204 void ImplicitExceptionTable::copy_to( nmethod* nm ) {
   205   assert(size_in_bytes() <= nm->nul_chk_table_size(), "size of space allocated in nmethod incorrect");
   206   if (len() != 0) {
   207     implicit_null_entry* nmdata = (implicit_null_entry*)nm->nul_chk_table_begin();
   208     // store the length in the first uint
   209     nmdata[0] = _len;
   210     nmdata++;
   211     // copy the table after the length
   212     memmove( nmdata, _data, 2 * len() * sizeof(implicit_null_entry));
   213   } else {
   214     // zero length table takes zero bytes
   215     assert(size_in_bytes() == 0, "bad size");
   216     assert(nm->nul_chk_table_size() == 0, "bad size");
   217   }
   218 }
   220 void ImplicitExceptionTable::verify(nmethod *nm) const {
   221   for (uint i = 0; i < len(); i++) {
   222      if ((*adr(i) > (unsigned int)nm->code_size()) ||
   223          (*(adr(i)+1) > (unsigned int)nm->code_size()))
   224        fatal(err_msg("Invalid offset in ImplicitExceptionTable at " PTR_FORMAT, _data));
   225   }
   226 }

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