1 /*
  2  * Copyright (c) 2020, 2023, Oracle and/or its affiliates. All rights reserved.
  3  * Copyright (c) 2020, 2023, Huawei Technologies Co., Ltd. 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 #include "precompiled.hpp"
 27 #include "opto/c2_CodeStubs.hpp"
 28 #include "opto/c2_MacroAssembler.hpp"
 29 #include "runtime/objectMonitor.hpp"
 30 #include "runtime/sharedRuntime.hpp"
 31 #include "runtime/stubRoutines.hpp"
 32 
 33 #define __ masm.
 34 
 35 int C2SafepointPollStub::max_size() const {
 36   return 13 * 4;
 37 }
 38 
 39 void C2SafepointPollStub::emit(C2_MacroAssembler& masm) {
 40   assert(SharedRuntime::polling_page_return_handler_blob() != nullptr,
 41          "polling page return stub not created yet");
 42   address stub = SharedRuntime::polling_page_return_handler_blob()->entry_point();
 43   RuntimeAddress callback_addr(stub);
 44 
 45   __ bind(entry());
 46   InternalAddress safepoint_pc(__ pc() - __ offset() + _safepoint_offset);
 47   __ relocate(safepoint_pc.rspec(), [&] {
 48     int32_t offset;
 49     __ la(t0, safepoint_pc.target(), offset);
 50     __ addi(t0, t0, offset);
 51   });
 52   __ sd(t0, Address(xthread, JavaThread::saved_exception_pc_offset()));
 53   __ far_jump(callback_addr);
 54 }
 55 
 56 int C2EntryBarrierStub::max_size() const {
 57   // 4 bytes for alignment
 58   return 8 * 4 + 4;
 59 }
 60 
 61 void C2EntryBarrierStub::emit(C2_MacroAssembler& masm) {
 62   __ bind(entry());
 63   __ rt_call(StubRoutines::method_entry_barrier());
 64 
 65   __ j(continuation());
 66 
 67   // make guard value 4-byte aligned so that it can be accessed by atomic instructions on RISC-V
 68   __ align(4);
 69   __ bind(guard());
 70   __ relocate(entry_guard_Relocation::spec());
 71   __ emit_int32(0);  // nmethod guard value
 72 }
 73 
 74 int C2HandleAnonOMOwnerStub::max_size() const {
 75   // Max size of stub has been determined by testing with 0 without using RISC-V compressed
 76   // instruction-set extension, in which case C2CodeStubList::emit() will throw an assertion
 77   // and report the actual size that is needed.
 78   return 20 DEBUG_ONLY(+8);
 79 }
 80 
 81 void C2HandleAnonOMOwnerStub::emit(C2_MacroAssembler& masm) {
 82   __ bind(entry());
 83   Register mon = monitor();
 84   Register t = tmp();
 85   assert(t != noreg, "need tmp register");
 86 
 87   // Fix owner to be the current thread.
 88   __ sd(xthread, Address(mon, ObjectMonitor::owner_offset()));
 89 
 90   // Pop owner object from lock-stack.
 91   __ lwu(t, Address(xthread, JavaThread::lock_stack_top_offset()));
 92   __ subw(t, t, oopSize);
 93 #ifdef ASSERT
 94   __ add(t0, xthread, t);
 95   __ sd(zr, Address(t0, 0));
 96 #endif
 97   __ sw(t, Address(xthread, JavaThread::lock_stack_top_offset()));
 98 
 99   __ j(continuation());
100 }
101 
102 #undef __