1 /*
   2  * Copyright 2003-2007 Sun Microsystems, Inc.  All Rights Reserved.
   3  * Copyright 2010 Red Hat, Inc.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  */
  25 
  26 #include "incls/_precompiled.incl"
  27 #include "incls/_stack_zero.cpp.incl"
  28 
  29 int ZeroStack::suggest_size(Thread *thread) const {
  30   assert(needs_setup(), "already set up");
  31   return align_size_down(abi_stack_available(thread) / 2, wordSize);
  32 }
  33 
  34 void ZeroStack::handle_overflow(TRAPS) {
  35   JavaThread *thread = (JavaThread *) THREAD;
  36 
  37   // Set up the frame anchor if it isn't already
  38   bool has_last_Java_frame = thread->has_last_Java_frame();
  39   if (!has_last_Java_frame) {
  40     intptr_t *sp = thread->zero_stack()->sp();
  41     ZeroFrame *frame = thread->top_zero_frame();
  42     while (frame) {
  43       if (frame->is_shark_frame())
  44         break;
  45 
  46       if (frame->is_interpreter_frame()) {
  47         interpreterState istate =
  48           frame->as_interpreter_frame()->interpreter_state();
  49         if (istate->self_link() == istate)
  50           break;
  51       }
  52 
  53       sp = ((intptr_t *) frame) + 1;
  54       frame = frame->next();
  55     }
  56 
  57     if (frame == NULL)
  58       fatal("unrecoverable stack overflow");
  59 
  60     thread->set_last_Java_frame(frame, sp);
  61   }
  62 
  63   // Throw the exception
  64   switch (thread->thread_state()) {
  65   case _thread_in_Java:
  66     InterpreterRuntime::throw_StackOverflowError(thread);
  67     break;
  68 
  69   case _thread_in_vm:
  70     Exceptions::throw_stack_overflow_exception(thread, __FILE__, __LINE__);
  71     break;
  72 
  73   default:
  74     ShouldNotReachHere();
  75   }
  76 
  77   // Reset the frame anchor if necessary
  78   if (!has_last_Java_frame)
  79     thread->reset_last_Java_frame();
  80 }
  81 
  82 #ifndef PRODUCT
  83 void ZeroStack::zap(int c) {
  84   memset(_base, c, available_words() * wordSize);
  85 }
  86 #endif // PRODUCT