1 /*

     2  * Copyright (c) 2008, 2011, 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 #ifndef CPU_ARM_VM_JAVAFRAMEANCHOR_ARM_HPP

    26 #define CPU_ARM_VM_JAVAFRAMEANCHOR_ARM_HPP

    27 

    28 private:

    29 

    30   // FP value associated with _last_Java_sp:

    31   intptr_t* volatile        _last_Java_fp;           // pointer is volatile not what it points to

    32 

    33 public:

    34   // Each arch must define reset, save, restore

    35   // These are used by objects that only care about:

    36   //  1 - initializing a new state (thread creation, javaCalls)

    37   //  2 - saving a current state (javaCalls)

    38   //  3 - restoring an old state (javaCalls)

    39 

    40   void clear(void) {

    41     // clearing _last_Java_sp must be first

    42     _last_Java_sp = NULL;

    43     // fence?

    44     _last_Java_fp = NULL;

    45     _last_Java_pc = NULL;

    46   }

    47 

    48   void copy(JavaFrameAnchor* src) {

    49     // In order to make sure the transition state is valid for "this"

    50     // We must clear _last_Java_sp before copying the rest of the new data

    51     //

    52     // Hack Alert: Temporary bugfix for 4717480/4721647

    53     // To act like previous version (pd_cache_state) don't NULL _last_Java_sp

    54     // unless the value is changing

    55     //

    56     if (_last_Java_sp != src->_last_Java_sp)

    57       _last_Java_sp = NULL;

    58 

    59     _last_Java_fp = src->_last_Java_fp;

    60     _last_Java_pc = src->_last_Java_pc;

    61     // Must be last so profiler will always see valid frame if has_last_frame() is true

    62     _last_Java_sp = src->_last_Java_sp;

    63   }

    64 

    65   // Always walkable

    66   bool walkable(void) { return true; }

    67   // Never any thing to do since we are always walkable and can find address of return addresses

    68   void make_walkable(JavaThread* thread) { }

    69 

    70   intptr_t* last_Java_sp(void) const             { return _last_Java_sp; }

    71 

    72   address last_Java_pc(void)                     { return _last_Java_pc; }

    73 

    74 private:

    75 

    76   static ByteSize last_Java_fp_offset()          { return byte_offset_of(JavaFrameAnchor, _last_Java_fp); }

    77 

    78 public:

    79 

    80   void set_last_Java_sp(intptr_t* sp)            { _last_Java_sp = sp; }

    81 

    82   intptr_t*   last_Java_fp(void)                     { return _last_Java_fp; }

    83   // Assert (last_Java_sp == NULL || fp == NULL)

    84   void set_last_Java_fp(intptr_t* fp)                { _last_Java_fp = fp; }

    85 

    86 #endif // CPU_ARM_VM_JAVAFRAMEANCHOR_ARM_HPP