1 /*
 2  * Copyright (c) 2020, 2022 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 #include "precompiled.hpp"
26 #include "opto/c2_MacroAssembler.hpp"
27 #include "opto/c2_CodeStubs.hpp"
28 #include "runtime/objectMonitor.hpp"
29 #include "runtime/sharedRuntime.hpp"
30 #include "runtime/stubRoutines.hpp"
31 
32 #define __ masm.
33 
34 int C2SafepointPollStub::max_size() const {
35   return 20;
36 }
37 
38 void C2SafepointPollStub::emit(C2_MacroAssembler& masm) {
39   assert(SharedRuntime::polling_page_return_handler_blob() != NULL,
40          "polling page return stub not created yet");
41   address stub = SharedRuntime::polling_page_return_handler_blob()->entry_point();
42 
43   RuntimeAddress callback_addr(stub);
44 
45   __ bind(entry());
46   InternalAddress safepoint_pc(masm.pc() - masm.offset() + _safepoint_offset);
47   __ adr(rscratch1, safepoint_pc);
48   __ str(rscratch1, Address(rthread, JavaThread::saved_exception_pc_offset()));
49   __ far_jump(callback_addr);
50 }
51 
52 int C2HandleAnonOMOwnerStub::max_size() const {
53   // Max size of stub has been determined by testing with 0, in which case
54   // C2CodeStubList::emit() will throw an assertion and report the actual size that
55   // is needed.
56   return 24;
57 }
58 
59 void C2HandleAnonOMOwnerStub::emit(C2_MacroAssembler& masm) {
60   __ bind(entry());
61   Register mon = monitor();
62   Register t = tmp();
63   assert(t != noreg, "need tmp register");
64 
65   // Fix owner to be the current thread.
66   __ str(rthread, Address(mon, ObjectMonitor::owner_offset_in_bytes()));
67 
68   // Pop owner object from lock-stack.
69   __ ldrw(t, Address(rthread, JavaThread::lock_stack_top_offset()));
70   __ subw(t, t, oopSize);
71 #ifdef ASSERT
72   __ str(zr, Address(rthread, t));
73 #endif
74   __ strw(t, Address(rthread, JavaThread::lock_stack_top_offset()));
75 
76   __ b(continuation());
77 }
78 
79 int C2LoadNKlassStub::max_size() const {
80   return 8;
81 }
82 
83 void C2LoadNKlassStub::emit(C2_MacroAssembler& masm) {
84   __ bind(entry());
85   Register d = dst();
86   __ ldr(d, Address(d, OM_OFFSET_NO_MONITOR_VALUE_TAG(header)));
87   __ b(continuation());
88 }
89 
90 
91 #undef __