1 /*
2  * Copyright (c) 2016, 2018, 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 #include "precompiled.hpp"
25 
26 #include "aot/compiledIC_aot.hpp"
27 #include "code/codeCache.hpp"
28 #include "memory/resourceArea.hpp"
29 
set_to_far(const methodHandle & callee,address entry)30 void CompiledDirectStaticCall::set_to_far(const methodHandle& callee, address entry) {
31   address stub = find_stub(true /* is_far */);
32   guarantee(stub != NULL, "stub not found");
33 
34   if (TraceICs) {
35     ResourceMark rm;
36     tty->print_cr("CompiledDirectStaticCall@" INTPTR_FORMAT ": set_to_far %s",
37                   p2i(instruction_address()),
38                   callee->name_and_sig_as_C_string());
39   }
40 
41   // Creation also verifies the object.
42   // mov rax,imm_aot_addr
43   // jmp rax
44   NativeMovConstReg* destination_holder = nativeMovConstReg_at(stub);
45 
46 #ifdef ASSERT
47   // read the value once
48   intptr_t data = destination_holder->data();
49   assert(data == 0 || data == (intptr_t)entry,
50          "MT-unsafe modification of inline cache");
51 #endif
52 
53   // Update stub.
54   destination_holder->set_data((intptr_t)entry);
55 
56   // Update jump to call.
57   set_destination_mt_safe(stub);
58 }
59 
set_to_interpreted(const methodHandle & callee,address entry)60 void CompiledPltStaticCall::set_to_interpreted(const methodHandle& callee, address entry) {
61   address stub = find_stub();
62   guarantee(stub != NULL, "stub not found");
63   if (TraceICs) {
64     ResourceMark rm;
65     tty->print_cr("CompiledPltStaticCall@" INTPTR_FORMAT ": set_to_interpreted %s",
66                   p2i(instruction_address()),
67                   callee->name_and_sig_as_C_string());
68   }
69 
70   // Creation also verifies the object.
71   NativeLoadGot* method_loader = nativeLoadGot_at(stub);
72   NativeGotJump* jump          = nativeGotJump_at(method_loader->next_instruction_address());
73 
74   intptr_t data = method_loader->data();
75   address destination = jump->destination();
76   assert(data == 0 || data == (intptr_t)callee(),
77          "a) MT-unsafe modification of inline cache");
78   assert(destination == (address)-1 || destination == entry,
79          "b) MT-unsafe modification of inline cache");
80 
81   // Update stub.
82   method_loader->set_data((intptr_t)callee());
83   jump->set_jump_destination(entry);
84 
85   // Update jump to call.
86   set_destination_mt_safe(stub);
87 }
88 
89 #ifdef NEVER_CALLED
set_stub_to_clean(static_stub_Relocation * static_stub)90 void CompiledPltStaticCall::set_stub_to_clean(static_stub_Relocation* static_stub) {
91   // Reset stub.
92   address stub = static_stub->addr();
93   assert(stub != NULL, "stub not found");
94   assert(CompiledICLocker::is_safe(stub), "mt unsafe call");
95   // Creation also verifies the object.
96   NativeLoadGot* method_loader = nativeLoadGot_at(stub);
97   NativeGotJump* jump          = nativeGotJump_at(method_loader->next_instruction_address());
98   method_loader->set_data(0);
99   jump->set_jump_destination((address)-1);
100 }
101 #endif
102 
103 #ifndef PRODUCT
verify()104 void CompiledPltStaticCall::verify() {
105   // Verify call.
106   _call->verify();
107 
108 #ifdef ASSERT
109   CodeBlob *cb = CodeCache::find_blob_unsafe((address) _call);
110   assert(cb && cb->is_aot(), "CompiledPltStaticCall can only be used on AOTCompiledMethod");
111 #endif
112 
113   // Verify stub.
114   address stub = find_stub();
115   assert(stub != NULL, "no stub found for static call");
116   // Creation also verifies the object.
117   NativeLoadGot*     method_loader = nativeLoadGot_at(stub);
118   NativeGotJump*     jump          = nativeGotJump_at(method_loader->next_instruction_address());
119   // Verify state.
120   assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
121 }
122 #endif // !PRODUCT
123