| /* |
| * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #ifndef SHARE_VM_CODE_STUBS_HPP |
| #define SHARE_VM_CODE_STUBS_HPP |
| |
| #include "asm/codeBuffer.hpp" |
| #include "memory/allocation.hpp" |
| #ifdef TARGET_OS_FAMILY_linux |
| # include "os_linux.inline.hpp" |
| #endif |
| #ifdef TARGET_OS_FAMILY_solaris |
| # include "os_solaris.inline.hpp" |
| #endif |
| #ifdef TARGET_OS_FAMILY_windows |
| # include "os_windows.inline.hpp" |
| #endif |
| #ifdef TARGET_OS_FAMILY_aix |
| # include "os_aix.inline.hpp" |
| #endif |
| #ifdef TARGET_OS_FAMILY_bsd |
| # include "os_bsd.inline.hpp" |
| #endif |
| |
| // The classes in this file provide a simple framework for the |
| // management of little pieces of machine code - or stubs - |
| // created on the fly and frequently discarded. In this frame- |
| // work stubs are stored in a queue. |
| |
| |
| // Stub serves as abstract base class. A concrete stub |
| // implementation is a subclass of Stub, implementing |
| // all (non-virtual!) functions required sketched out |
| // in the Stub class. |
| // |
| // A concrete stub layout may look like this (both data |
| // and code sections could be empty as well): |
| // |
| // ________ |
| // stub -->| | <--+ |
| // | data | | |
| // |________| | |
| // code_begin -->| | | |
| // | | | |
| // | code | | size |
| // | | | |
| // |________| | |
| // code_end -->| | | |
| // | data | | |
| // |________| | |
| // <--+ |
| |
| |
| class Stub VALUE_OBJ_CLASS_SPEC { |
| public: |
| // Initialization/finalization |
| void initialize(int size, |
| CodeStrings& strings) { ShouldNotCallThis(); } // called to initialize/specify the stub's size |
| void finalize() { ShouldNotCallThis(); } // called before the stub is deallocated |
| |
| // General info/converters |
| int size() const { ShouldNotCallThis(); return 0; } // must return the size provided by initialize |
| static int code_size_to_size(int code_size) { ShouldNotCallThis(); return 0; } // computes the size given the code size |
| |
| // Code info |
| address code_begin() const { ShouldNotCallThis(); return NULL; } // points to the first byte of the code |
| address code_end() const { ShouldNotCallThis(); return NULL; } // points to the first byte after the code |
| |
| // Debugging |
| void verify() { ShouldNotCallThis(); } // verifies the Stub |
| void print() { ShouldNotCallThis(); } // prints some information about the stub |
| }; |
| |
| |
| // A stub interface defines the interface between a stub queue |
| // and the stubs it queues. In order to avoid a vtable and |
| // (and thus the extra word) in each stub, a concrete stub |
| // interface object is created and associated with a stub |
| // buffer which in turn uses the stub interface to interact |
| // with its stubs. |
| // |
| // StubInterface serves as an abstract base class. A concrete |
| // stub interface implementation is a subclass of StubInterface, |
| // forwarding its virtual function calls to non-virtual calls |
| // of the concrete stub (see also macro below). There's exactly |
| // one stub interface instance required per stub queue. |
| |
| class StubInterface: public CHeapObj<mtCode> { |
| public: |
| // Initialization/finalization |
| virtual void initialize(Stub* self, int size, |
| CodeStrings& strings) = 0; // called after creation (called twice if allocated via (request, commit)) |
| virtual void finalize(Stub* self) = 0; // called before deallocation |
| |
| // General info/converters |
| virtual int size(Stub* self) const = 0; // the total size of the stub in bytes (must be a multiple of CodeEntryAlignment) |
| virtual int code_size_to_size(int code_size) const = 0; // computes the total stub size in bytes given the code size in bytes |
| |
| // Code info |
| virtual address code_begin(Stub* self) const = 0; // points to the first code byte |
| virtual address code_end(Stub* self) const = 0; // points to the first byte after the code |
| |
| // Debugging |
| virtual void verify(Stub* self) = 0; // verifies the stub |
| virtual void print(Stub* self) = 0; // prints information about the stub |
| }; |
| |
| |
| // DEF_STUB_INTERFACE is used to create a concrete stub interface |
| // class, forwarding stub interface calls to the corresponding |
| // stub calls. |
| |
| #define DEF_STUB_INTERFACE(stub) \ |
| class stub##Interface: public StubInterface { \ |
| private: \ |
| static stub* cast(Stub* self) { return (stub*)self; } \ |
| \ |
| public: \ |
| /* Initialization/finalization */ \ |
| virtual void initialize(Stub* self, int size, \ |
| CodeStrings& strings) { cast(self)->initialize(size, strings); } \ |
| virtual void finalize(Stub* self) { cast(self)->finalize(); } \ |
| \ |
| /* General info */ \ |
| virtual int size(Stub* self) const { return cast(self)->size(); } \ |
| virtual int code_size_to_size(int code_size) const { return stub::code_size_to_size(code_size); } \ |
| \ |
| /* Code info */ \ |
| virtual address code_begin(Stub* self) const { return cast(self)->code_begin(); } \ |
| virtual address code_end(Stub* self) const { return cast(self)->code_end(); } \ |
| \ |
| /* Debugging */ \ |
| virtual void verify(Stub* self) { cast(self)->verify(); } \ |
| virtual void print(Stub* self) { cast(self)->print(); } \ |
| }; |
| |
| |
| // A StubQueue maintains a queue of stubs. |
| // Note: All sizes (spaces) are given in bytes. |
| |
| class StubQueue: public CHeapObj<mtCode> { |
| friend class VMStructs; |
| private: |
| StubInterface* _stub_interface; // the interface prototype |
| address _stub_buffer; // where all stubs are stored |
| int _buffer_size; // the buffer size in bytes |
| int _buffer_limit; // the (byte) index of the actual buffer limit (_buffer_limit <= _buffer_size) |
| int _queue_begin; // the (byte) index of the first queue entry (word-aligned) |
| int _queue_end; // the (byte) index of the first entry after the queue (word-aligned) |
| int _number_of_stubs; // the number of buffered stubs |
| Mutex* const _mutex; // the lock used for a (request, commit) transaction |
| |
| void check_index(int i) const { assert(0 <= i && i < _buffer_limit && i % CodeEntryAlignment == 0, "illegal index"); } |
| bool is_contiguous() const { return _queue_begin <= _queue_end; } |
| int index_of(Stub* s) const { int i = (address)s - _stub_buffer; check_index(i); return i; } |
| Stub* stub_at(int i) const { check_index(i); return (Stub*)(_stub_buffer + i); } |
| Stub* current_stub() const { return stub_at(_queue_end); } |
| |
| // Stub functionality accessed via interface |
| void stub_initialize(Stub* s, int size, |
| CodeStrings& strings) { assert(size % CodeEntryAlignment == 0, "size not aligned"); _stub_interface->initialize(s, size, strings); } |
| void stub_finalize(Stub* s) { _stub_interface->finalize(s); } |
| int stub_size(Stub* s) const { return _stub_interface->size(s); } |
| bool stub_contains(Stub* s, address pc) const { return _stub_interface->code_begin(s) <= pc && pc < _stub_interface->code_end(s); } |
| int stub_code_size_to_size(int code_size) const { return _stub_interface->code_size_to_size(code_size); } |
| void stub_verify(Stub* s) { _stub_interface->verify(s); } |
| void stub_print(Stub* s) { _stub_interface->print(s); } |
| |
| static void register_queue(StubQueue*); |
| |
| public: |
| StubQueue(StubInterface* stub_interface, int buffer_size, Mutex* lock, |
| const char* name); |
| ~StubQueue(); |
| |
| // General queue info |
| bool is_empty() const { return _queue_begin == _queue_end; } |
| int total_space() const { return _buffer_size - 1; } |
| int available_space() const { int d = _queue_begin - _queue_end - 1; return d < 0 ? d + _buffer_size : d; } |
| int used_space() const { return total_space() - available_space(); } |
| int number_of_stubs() const { return _number_of_stubs; } |
| bool contains(address pc) const { return _stub_buffer <= pc && pc < _stub_buffer + _buffer_limit; } |
| Stub* stub_containing(address pc) const; |
| address code_start() const { return _stub_buffer; } |
| address code_end() const { return _stub_buffer + _buffer_limit; } |
| |
| // Stub allocation (atomic transactions) |
| Stub* request_committed(int code_size); // request a stub that provides exactly code_size space for code |
| Stub* request(int requested_code_size); // request a stub with a (maximum) code space - locks the queue |
| void commit (int committed_code_size, |
| CodeStrings& strings); // commit the previously requested stub - unlocks the queue |
| |
| // Stub deallocation |
| void remove_first(); // remove the first stub in the queue |
| void remove_first(int n); // remove the first n stubs in the queue |
| void remove_all(); // remove all stubs in the queue |
| |
| // Iteration |
| static void queues_do(void f(StubQueue* s)); // call f with each StubQueue |
| void stubs_do(void f(Stub* s)); // call f with all stubs |
| Stub* first() const { return number_of_stubs() > 0 ? stub_at(_queue_begin) : NULL; } |
| Stub* next(Stub* s) const { int i = index_of(s) + stub_size(s); |
| if (i == _buffer_limit) i = 0; |
| return (i == _queue_end) ? NULL : stub_at(i); |
| } |
| |
| address stub_code_begin(Stub* s) const { return _stub_interface->code_begin(s); } |
| address stub_code_end(Stub* s) const { return _stub_interface->code_end(s); } |
| |
| // Debugging/printing |
| void verify(); // verifies the stub queue |
| void print(); // prints information about the stub queue |
| }; |
| |
| #endif // SHARE_VM_CODE_STUBS_HPP |
