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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
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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
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
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package com.oracle.truffle.llvm.runtime.nodes.asm;

import java.security.SecureRandom;

import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
import com.oracle.truffle.api.dsl.Specialization;
import com.oracle.truffle.api.frame.VirtualFrame;
import com.oracle.truffle.llvm.runtime.nodes.asm.support.LLVMAMD64WriteBooleanNode;
import com.oracle.truffle.llvm.runtime.nodes.api.LLVMExpressionNode;

public abstract class LLVMAMD64RdRandNode extends LLVMExpressionNode {
    private final SecureRandom random = new SecureRandom();

    @Child protected LLVMAMD64WriteBooleanNode writeCFNode;

    // TODO: OF, SF, ZF, AF, PF = 0

    @TruffleBoundary
    protected int nextInt() {
        return random.nextInt();
    }

    @TruffleBoundary
    protected long nextLong() {
        return random.nextLong();
    }

    public LLVMAMD64RdRandNode(LLVMAMD64WriteBooleanNode writeCFNode) {
        this.writeCFNode = writeCFNode;
    }

    public abstract static class LLVMAMD64RdRandwNode extends LLVMAMD64RdRandNode {
        public LLVMAMD64RdRandwNode(LLVMAMD64WriteBooleanNode writeCFNode) {
            super(writeCFNode);
        }

        @Specialization
        protected short doI16(VirtualFrame frame) {
            writeCFNode.execute(frame, true);
            return (short) nextInt();
        }
    }

    public abstract static class LLVMAMD64RdRandlNode extends LLVMAMD64RdRandNode {
        public LLVMAMD64RdRandlNode(LLVMAMD64WriteBooleanNode cf) {
            super(cf);
        }

        @Specialization
        protected int doI32(VirtualFrame frame) {
            writeCFNode.execute(frame, true);
            return nextInt();
        }
    }

    public abstract static class LLVMAMD64RdRandqNode extends LLVMAMD64RdRandNode {
        public LLVMAMD64RdRandqNode(LLVMAMD64WriteBooleanNode cf) {
            super(cf);
        }

        @Specialization
        protected long doI64(VirtualFrame frame) {
            writeCFNode.execute(frame, true);
            return nextLong();
        }
    }
}