/*

 * 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

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 */

package org.graalvm.compiler.core.common.type;

import org.graalvm.compiler.core.common.LIRKind;

import org.graalvm.compiler.core.common.spi.LIRKindTool;

import org.graalvm.compiler.debug.GraalError;

import jdk.vm.ci.meta.Constant;

import jdk.vm.ci.meta.JavaKind;

import jdk.vm.ci.meta.MemoryAccessProvider;

import jdk.vm.ci.meta.MetaAccessProvider;

import jdk.vm.ci.meta.PrimitiveConstant;

import jdk.vm.ci.meta.ResolvedJavaType;

/**

 * This stamp represents the type of the {@link JavaKind#Illegal} value in the second slot of

 * {@link JavaKind#Long} and {@link JavaKind#Double} values. It can only appear in framestates or

 * virtual objects.

 */

public final class IllegalStamp extends Stamp {

    private IllegalStamp() {

    }

    @Override

    public void accept(Visitor v) {

    }

    @Override

    public JavaKind getStackKind() {

        return JavaKind.Illegal;

    }

    @Override

    public LIRKind getLIRKind(LIRKindTool tool) {

        return LIRKind.Illegal;

    }

    @Override

    public Stamp unrestricted() {

        return this;

    }

    @Override

    public boolean isUnrestricted() {

        return true;

    }

    @Override

    public Stamp empty() {

        return this;

    }

    @Override

    public Stamp constant(Constant c, MetaAccessProvider meta) {

        assert ((PrimitiveConstant) c).getJavaKind() == JavaKind.Illegal;

        return this;

    }

    @Override

    public ResolvedJavaType javaType(MetaAccessProvider metaAccess) {

        throw GraalError.shouldNotReachHere("illegal stamp has no Java type");

    }

    @Override

    public Stamp meet(Stamp other) {

        assert other instanceof IllegalStamp;

        return this;

    }

    @Override

    public Stamp join(Stamp other) {

        assert other instanceof IllegalStamp;

        return this;

    }

    @Override

    public boolean isCompatible(Stamp stamp) {

        return stamp instanceof IllegalStamp;

    }

    @Override

    public boolean isCompatible(Constant constant) {

        if (constant instanceof PrimitiveConstant) {

            PrimitiveConstant prim = (PrimitiveConstant) constant;

            return prim.getJavaKind() == JavaKind.Illegal;

        }

        return false;

    }

    @Override

    public String toString() {

        return "ILLEGAL";

    }

    @Override

    public boolean hasValues() {

        return true;

    }

    @Override

    public Stamp improveWith(Stamp other) {

        assert other instanceof IllegalStamp;

        return this;

    }

    @Override

    public Constant readConstant(MemoryAccessProvider provider, Constant base, long displacement) {

        throw GraalError.shouldNotReachHere("can't read values of illegal stamp");

    }

    private static final IllegalStamp instance = new IllegalStamp();

    static IllegalStamp getInstance() {

        return instance;

    }

}