hotspot/src/jdk.vm.compiler/share/classes/org.graalvm.compiler.hotspot.aarch64/src/org/graalvm/compiler/hotspot/aarch64/AArch64HotSpotPatchReturnAddressOp.java

/*
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 * 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.
 *
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package org.graalvm.compiler.hotspot.aarch64;

import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.REG;
import static jdk.vm.ci.aarch64.AArch64.sp;
import static jdk.vm.ci.code.ValueUtil.asRegister;

import org.graalvm.compiler.asm.aarch64.AArch64Address;
import org.graalvm.compiler.asm.aarch64.AArch64MacroAssembler;
import org.graalvm.compiler.asm.aarch64.AArch64MacroAssembler.AArch64ExceptionCode;
import org.graalvm.compiler.lir.LIRInstructionClass;
import org.graalvm.compiler.lir.Opcode;
import org.graalvm.compiler.lir.aarch64.AArch64LIRInstruction;
import org.graalvm.compiler.lir.asm.CompilationResultBuilder;

import jdk.vm.ci.meta.AllocatableValue;

/**
 * Patch the return address of the current frame.
 */
@Opcode("PATCH_RETURN")
final class AArch64HotSpotPatchReturnAddressOp extends AArch64LIRInstruction {

    public static final LIRInstructionClass<AArch64HotSpotPatchReturnAddressOp> TYPE = LIRInstructionClass.create(AArch64HotSpotPatchReturnAddressOp.class);

    @Use(REG) AllocatableValue address;

    AArch64HotSpotPatchReturnAddressOp(AllocatableValue address) {
        super(TYPE);
        this.address = address;
    }

    @Override
    public void emitCode(CompilationResultBuilder crb, AArch64MacroAssembler masm) {
        final int frameSize = crb.frameMap.frameSize();
        // XXX where is lr exactly?
        AArch64Address lrAddress = AArch64Address.createUnscaledImmediateAddress(sp, frameSize);
        masm.brk(AArch64ExceptionCode.BREAKPOINT); // XXX
        masm.str(64, asRegister(address), lrAddress);
    }
}