1 /*

     2  * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.

     3  * Copyright (c) 2016 SAP SE. All rights reserved.

     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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    21  * or visit www.oracle.com if you need additional information or have any

    22  * questions.

    23  *

    24  */

    25 

    26 #ifndef CPU_S390_VM_JAVAFRAMEANCHOR_S390_HPP

    27 #define CPU_S390_VM_JAVAFRAMEANCHOR_S390_HPP

    28 

    29  public:

    30 

    31   // Each arch must define reset, save, restore.

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

    33   //  1 - initializing a new state (thread creation, javaCalls)

    34   //  2 - saving a current state (javaCalls)

    35   //  3 - restoring an old state (javaCalls).

    36 

    37   inline void clear(void) {

    38     // Clearing _last_Java_sp must be first.

    39     OrderAccess::release();

    40     _last_Java_sp = NULL;

    41     // Fence?

    42     OrderAccess::fence();

    43 

    44     _last_Java_pc = NULL;

    45   }

    46 

    47   inline void set(intptr_t* sp, address pc) {

    48     _last_Java_pc = pc;

    49 

    50     OrderAccess::release();

    51     _last_Java_sp = sp;

    52   }

    53 

    54   void copy(JavaFrameAnchor* src) {

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

    56     // we must clear _last_Java_sp before copying the rest of the new data.

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

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

    59     // unless the value is changing.

    60     //

    61     if (_last_Java_sp != src->_last_Java_sp) {

    62       OrderAccess::release();

    63       _last_Java_sp = NULL;

    64       OrderAccess::fence();

    65     }

    66     _last_Java_pc = src->_last_Java_pc;

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

    68 

    69     OrderAccess::release();

    70     _last_Java_sp = src->_last_Java_sp;

    71   }

    72 

    73   // We don't have to flush registers, so the stack is always walkable.

    74   inline bool walkable(void) { return true; }

    75   inline void make_walkable(JavaThread* thread) { }

    76 

    77  public:

    78 

    79   // We don't have a frame pointer.

    80   intptr_t* last_Java_fp(void)        { return NULL; }

    81 

    82   intptr_t* last_Java_sp() const      { return _last_Java_sp; }

    83   void set_last_Java_sp(intptr_t* sp) { OrderAccess::release(); _last_Java_sp = sp; }

    84 

    85   address last_Java_pc(void)          { return _last_Java_pc; }

    86 

    87 #endif // CPU_S390_VM_JAVAFRAMEANCHOR_S390_HPP