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 * 3. Neither the name of the copyright holder nor the names of its contributors may be used to
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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.nodes.asm;

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.nodes.asm.LLVMAMD64RdtscNodeGen.LLVMAMD64RdtscReadNodeGen;
import com.oracle.truffle.llvm.nodes.asm.support.LLVMAMD64WriteRegisterNode.LLVMAMD64WriteI64RegisterNode;
import com.oracle.truffle.llvm.runtime.nodes.api.LLVMExpressionNode;

public abstract class LLVMAMD64RdtscNode extends LLVMExpressionNode {
    private final LLVMAMD64WriteI64RegisterNode low;
    private final LLVMAMD64WriteI64RegisterNode high;
    private final LLVMExpressionNode rdtsc;

    public LLVMAMD64RdtscNode(LLVMAMD64WriteI64RegisterNode low, LLVMAMD64WriteI64RegisterNode high) {
        this.low = low;
        this.high = high;
        rdtsc = LLVMAMD64RdtscReadNodeGen.create();
    }

    @Specialization
    public Object execute(VirtualFrame frame) {
        long value = rdtsc.executeI64(frame);
        long lo = value & LLVMExpressionNode.I32_MASK;
        long hi = (value >> LLVMExpressionNode.I32_SIZE_IN_BITS) & LLVMExpressionNode.I32_MASK;
        low.execute(frame, lo);
        high.execute(frame, hi);
        return null;
    }

    public abstract static class LLVMAMD64RdtscReadNode extends LLVMExpressionNode {
        @TruffleBoundary
        @Specialization
        public long executeRdtsc() {
            return System.currentTimeMillis();
        }
    }
}