Mon, 23 Jun 2008 14:11:12 -0700
6708714: Optimize long LShift on 32-bits x86
Summary: For small (1-3 bits) left long shifts in 32-bits VM use sets of add+addc instructions instead of shld+shl on new AMD cpus.
Reviewed-by: never
Contributed-by: shrinivas.joshi@amd.com
duke@435 | 1 | /* |
duke@435 | 2 | * Copyright 2005 Sun Microsystems, Inc. All Rights Reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
duke@435 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
duke@435 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
duke@435 | 21 | * have any questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | #ifdef CHECK_UNHANDLED_OOPS |
duke@435 | 25 | |
duke@435 | 26 | // Detect unhanded oops in VM code |
duke@435 | 27 | |
duke@435 | 28 | // The design is that when an oop is declared on the stack as a local |
duke@435 | 29 | // variable, the oop is actually a C++ struct with constructor and |
duke@435 | 30 | // destructor. The constructor adds the oop address on a list |
duke@435 | 31 | // off each thread and the destructor removes the oop. At a potential |
duke@435 | 32 | // safepoint, the stack addresses of the local variable oops are trashed |
duke@435 | 33 | // with a recognizeable value. If the local variable is used again, it |
duke@435 | 34 | // will segfault, indicating an unsafe use of that oop. |
duke@435 | 35 | // eg: |
duke@435 | 36 | // oop o; //register &o on list |
duke@435 | 37 | // funct(); // if potential safepoint - causes clear_naked_oops() |
duke@435 | 38 | // // which trashes o above. |
duke@435 | 39 | // o->do_something(); // Crashes because o is unsafe. |
duke@435 | 40 | // |
duke@435 | 41 | // This code implements the details of the unhandled oop list on the thread. |
duke@435 | 42 | // |
duke@435 | 43 | |
duke@435 | 44 | class oop; |
duke@435 | 45 | class Thread; |
duke@435 | 46 | |
duke@435 | 47 | class UnhandledOopEntry { |
duke@435 | 48 | friend class UnhandledOops; |
duke@435 | 49 | private: |
duke@435 | 50 | oop* _oop_ptr; |
duke@435 | 51 | bool _ok_for_gc; |
duke@435 | 52 | address _pc; |
duke@435 | 53 | public: |
duke@435 | 54 | oop* oop_ptr() { return _oop_ptr; } |
duke@435 | 55 | UnhandledOopEntry() : _oop_ptr(NULL), _ok_for_gc(false), _pc(NULL) {} |
duke@435 | 56 | UnhandledOopEntry(oop* op, address pc) : |
duke@435 | 57 | _oop_ptr(op), _ok_for_gc(false), _pc(pc) {} |
duke@435 | 58 | }; |
duke@435 | 59 | |
duke@435 | 60 | |
duke@435 | 61 | class UnhandledOops { |
duke@435 | 62 | friend class Thread; |
duke@435 | 63 | private: |
duke@435 | 64 | Thread* _thread; |
duke@435 | 65 | int _level; |
duke@435 | 66 | GrowableArray<UnhandledOopEntry> *_oop_list; |
duke@435 | 67 | void allow_unhandled_oop(oop* op); |
duke@435 | 68 | void clear_unhandled_oops(); |
duke@435 | 69 | UnhandledOops(Thread* thread); |
duke@435 | 70 | ~UnhandledOops(); |
duke@435 | 71 | |
duke@435 | 72 | public: |
duke@435 | 73 | static void dump_oops(UnhandledOops* list); |
duke@435 | 74 | void register_unhandled_oop(oop* op, address pc); |
duke@435 | 75 | void unregister_unhandled_oop(oop* op); |
duke@435 | 76 | }; |
duke@435 | 77 | |
duke@435 | 78 | #ifdef _LP64 |
duke@435 | 79 | const intptr_t BAD_OOP_ADDR = 0xfffffffffffffff1; |
duke@435 | 80 | #else |
duke@435 | 81 | const intptr_t BAD_OOP_ADDR = 0xfffffff1; |
duke@435 | 82 | #endif // _LP64 |
duke@435 | 83 | #endif // CHECK_UNHANDLED_OOPS |