/*

 * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved.

 * 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

 * questions.

 */

package jdk.tools.jaotc;

import jdk.tools.jaotc.binformat.BinaryContainer;

import jdk.tools.jaotc.binformat.Relocation.RelocType;

import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage;

import jdk.vm.ci.code.site.Call;

/**

 * This is a foreign call site. This means either a call to the VM or a call to a Graal stub. If

 * it's a call directly to the VM, mangle the name. The call should go through regular .plt used by

 * the system loader, at least for now. If it's a call to a Graal stub, it should always be a direct

 * call, since the Graal stubs are contained within the .so file.

 */

final class ForeignCallSiteRelocationInfo extends CallSiteRelocationInfo {

    ForeignCallSiteRelocationInfo(Call call, HotSpotForeignCallLinkage callTarget) {

        super(getTargetSymbol(call, callTarget), getRelocType(callTarget));

    }

    private static String getTargetSymbol(Call call, HotSpotForeignCallLinkage callTarget) {

        // If it specifies a foreign call linkage, find the symbol corresponding to the address in

        // HotSpotVMConfig's fields.

        final long foreignCallTargetAddress = callTarget.getAddress();

        // Get the C/C++ function name associated with the foreign call target address.

        String functionName = DataBuilder.getVMFunctionNameForAddress(foreignCallTargetAddress);

        if (functionName != null) {

            // Use the known global AOT symbol associated with function name, if one exists

            String aotSymbol = BinaryContainer.getAOTSymbolForVMFunctionName(functionName);

            if (aotSymbol == null) {

                throw new InternalError("no global symbol found for: " + functionName);

            }

            return aotSymbol;

        }

        // Is it a Graal stub we are calling?

        if (callTarget.isCompiledStub()) {

            assert call.direct : "Should always be a direct call to stubs";

            return callTarget.getSymbol();

        }

        throw new InternalError("no symbol found for: " + callTarget);

    }

    private static RelocType getRelocType(HotSpotForeignCallLinkage callTarget) {

        return callTarget.isCompiledStub() ? RelocType.STUB_CALL_DIRECT : RelocType.FOREIGN_CALL_INDIRECT_GOT;

    }

}