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 * Redistribution and use in source and binary forms, with or without modification, are
 * permitted provided that the following conditions are met:
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 * 1. Redistributions of source code must retain the above copyright notice, this list of
 * conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other materials provided
 * with the distribution.
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 * 3. Neither the name of the copyright holder nor the names of its contributors may be used to
 * endorse or promote products derived from this software without specific prior written
 * permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
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package com.oracle.truffle.llvm.runtime.nodes.base;

import com.oracle.truffle.api.CompilerAsserts;
import com.oracle.truffle.api.CompilerDirectives;
import com.oracle.truffle.api.frame.FrameSlot;
import com.oracle.truffle.api.frame.FrameSlotKind;
import com.oracle.truffle.api.frame.VirtualFrame;

public final class LLVMFrameNullerUtil {
    private LLVMFrameNullerUtil() {
        // no instances
    }

    public static void nullFrameSlot(VirtualFrame frame, FrameSlot frameSlot) {
        CompilerAsserts.partialEvaluationConstant(frameSlot);
        if (CompilerDirectives.inInterpreter()) {
            // Nulling frame slots is only necessary in compiled code (otherwise, we would compute
            // values that are only used in framestates). This code must NOT be moved to a separate
            // method as it would cause endless deopts (the method or classes that are used within
            // the method might be unresolved because they were never executed). For the same
            // reason, we also must NOT use a switch statement.
            return;
        }
        FrameSlotKind kind = frame.getFrameDescriptor().getFrameSlotKind(frameSlot);
        if (kind == FrameSlotKind.Object) {
            frame.setObject(frameSlot, null);
        } else if (kind == FrameSlotKind.Boolean) {
            frame.setBoolean(frameSlot, false);
        } else if (kind == FrameSlotKind.Byte) {
            frame.setByte(frameSlot, (byte) 0);
        } else if (kind == FrameSlotKind.Int) {
            frame.setInt(frameSlot, 0);
        } else if (kind == FrameSlotKind.Long) {
            frame.setLong(frameSlot, 0L);
        } else if (kind == FrameSlotKind.Float) {
            frame.setFloat(frameSlot, 0f);
        } else if (kind == FrameSlotKind.Double) {
            frame.setDouble(frameSlot, 0d);
        } else {
            CompilerDirectives.transferToInterpreter();
            throw new UnsupportedOperationException("unexpected frameslot kind");
        }
    }
}