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package com.oracle.svm.core.graal.amd64;
import org.graalvm.compiler.asm.amd64.AMD64Address.Scale;
import org.graalvm.compiler.core.amd64.AMD64AddressNode;
import org.graalvm.compiler.core.amd64.AMD64CompressAddressLowering;
import org.graalvm.compiler.core.common.CompressEncoding;
import org.graalvm.compiler.nodes.CompressionNode;
import org.graalvm.compiler.nodes.ValueNode;
import com.oracle.svm.core.ReservedRegisters;
import com.oracle.svm.core.SubstrateOptions;
import jdk.vm.ci.code.Register;
public class SubstrateAMD64AddressLowering extends AMD64CompressAddressLowering {
private final long heapBase;
private final Register heapBaseRegister;
public SubstrateAMD64AddressLowering(CompressEncoding encoding) {
heapBase = encoding.getBase();
heapBaseRegister = ReservedRegisters.singleton().getHeapBaseRegister();
}
@Override
protected final boolean improveUncompression(AMD64AddressNode addr, CompressionNode compression, ValueNode other) {
assert SubstrateOptions.SpawnIsolates.getValue();
CompressEncoding encoding = compression.getEncoding();
if (!Scale.isScaleShiftSupported(encoding.getShift())) {
return false;
}
long encodingBase = encoding.getBase();
ValueNode base = other;
if (heapBaseRegister != null && encodingBase == heapBase) {
if (other != null) {
return false;
}
base = compression.graph().unique(new HeapBaseNode(heapBaseRegister));
} else if (encodingBase != 0) {
if (!updateDisplacement(addr, encodingBase, false)) {
return false;
}
}
Scale scale = Scale.fromShift(encoding.getShift());
addr.setBase(base);
addr.setScale(scale);
addr.setIndex(compression.getValue());
return true;
}
}