/*

 * Copyright (c) 2013, 2019, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package org.graalvm.compiler.hotspot.aarch64;

import static jdk.vm.ci.aarch64.AArch64.sp;

import static jdk.vm.ci.code.ValueUtil.asRegister;

import static jdk.vm.ci.hotspot.aarch64.AArch64HotSpotRegisterConfig.fp;

import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.REG;

import org.graalvm.compiler.asm.Label;

import org.graalvm.compiler.asm.aarch64.AArch64Address;

import org.graalvm.compiler.asm.aarch64.AArch64MacroAssembler;

import org.graalvm.compiler.asm.aarch64.AArch64MacroAssembler.ScratchRegister;

import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;

import org.graalvm.compiler.lir.LIRInstructionClass;

import org.graalvm.compiler.lir.Opcode;

import org.graalvm.compiler.lir.asm.CompilationResultBuilder;

import org.graalvm.compiler.serviceprovider.JavaVersionUtil;

import jdk.vm.ci.code.Register;

import jdk.vm.ci.meta.AllocatableValue;

/**

 * Sets up the arguments for an exception handler in the callers frame, removes the current frame

 * and jumps to the handler.

 */

@Opcode("JUMP_TO_EXCEPTION_HANDLER_IN_CALLER")

public class AArch64HotSpotJumpToExceptionHandlerInCallerOp extends AArch64HotSpotEpilogueOp {

    public static final LIRInstructionClass<AArch64HotSpotJumpToExceptionHandlerInCallerOp> TYPE = LIRInstructionClass.create(AArch64HotSpotJumpToExceptionHandlerInCallerOp.class);

    @Use(REG) private AllocatableValue handlerInCallerPc;

    @Use(REG) private AllocatableValue exception;

    @Use(REG) private AllocatableValue exceptionPc;

    private final Register thread;

    private final int isMethodHandleReturnOffset;

    public AArch64HotSpotJumpToExceptionHandlerInCallerOp(AllocatableValue handlerInCallerPc, AllocatableValue exception, AllocatableValue exceptionPc, int isMethodHandleReturnOffset,

                    Register thread, GraalHotSpotVMConfig config) {

        super(TYPE, config);

        this.handlerInCallerPc = handlerInCallerPc;

        this.exception = exception;

        this.exceptionPc = exceptionPc;

        this.isMethodHandleReturnOffset = isMethodHandleReturnOffset;

        this.thread = thread;

    }

    @Override

    public void emitCode(CompilationResultBuilder crb, AArch64MacroAssembler masm) {

        leaveFrame(crb, masm, /* emitSafepoint */false, false);

        if (JavaVersionUtil.JAVA_SPEC < 8) {

            // Restore sp from fp if the exception PC is a method handle call site.

            try (ScratchRegister sc = masm.getScratchRegister()) {

                Register scratch = sc.getRegister();

                final boolean allowOverwrite = false;

                AArch64Address address = masm.makeAddress(thread, isMethodHandleReturnOffset, scratch, 4, allowOverwrite);

                masm.ldr(32, scratch, address);

                Label noRestore = new Label();

                masm.cbz(32, scratch, noRestore);

                masm.mov(64, sp, fp);

                masm.bind(noRestore);

            }

        }

        masm.jmp(asRegister(handlerInCallerPc));

    }

}