1/*
2 * Copyright (c) 2013, 2015, 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 */
23package org.graalvm.compiler.hotspot.aarch64;
24
25import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.ILLEGAL;
26import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.REG;
27import static jdk.vm.ci.aarch64.AArch64.lr;
28import static jdk.vm.ci.code.ValueUtil.asRegister;
29
30import org.graalvm.compiler.asm.aarch64.AArch64MacroAssembler;
31import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;
32import org.graalvm.compiler.lir.LIRInstructionClass;
33import org.graalvm.compiler.lir.Opcode;
34import org.graalvm.compiler.lir.asm.CompilationResultBuilder;
35
36import jdk.vm.ci.meta.Value;
37
38/**
39 * Returns from a function.
40 */
41@Opcode("RETURN")
42public final class AArch64HotSpotReturnOp extends AArch64HotSpotEpilogueOp {
43
44    public static final LIRInstructionClass<AArch64HotSpotReturnOp> TYPE = LIRInstructionClass.create(AArch64HotSpotReturnOp.class);
45
46    @Use({REG, ILLEGAL}) private Value result;
47    private final boolean isStub;
48
49    public AArch64HotSpotReturnOp(Value result, boolean isStub, GraalHotSpotVMConfig config) {
50        super(TYPE, config);
51        assert validReturnValue(result);
52        this.result = result;
53        this.isStub = isStub;
54    }
55
56    private static boolean validReturnValue(Value result) {
57        if (result.equals(Value.ILLEGAL)) {
58            return true;
59        }
60        return asRegister(result).encoding == 0;
61    }
62
63    @Override
64    public void emitCode(CompilationResultBuilder crb, AArch64MacroAssembler masm) {
65        final boolean emitSafepoint = !isStub;
66        leaveFrame(crb, masm, emitSafepoint);
67        masm.ret(lr);
68    }
69}
70