/*
 * Copyright (c) 2013, 2014, 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 com.oracle.graal.hotspot;

import static com.oracle.graal.api.code.BytecodeFrame.*;

import com.oracle.graal.api.code.*;
import com.oracle.graal.api.meta.*;
import com.oracle.graal.compiler.gen.*;
import com.oracle.graal.graph.*;
import com.oracle.graal.nodes.*;
import com.oracle.jvmci.common.*;

/**
 * Extends {@link DebugInfoBuilder} to allocate the extra debug information required for locks.
 */
public class HotSpotDebugInfoBuilder extends DebugInfoBuilder {

    private final HotSpotLockStack lockStack;

    public HotSpotDebugInfoBuilder(NodeMap<Value> nodeOperands, HotSpotLockStack lockStack) {
        super(nodeOperands);
        this.lockStack = lockStack;
    }

    public HotSpotLockStack lockStack() {
        return lockStack;
    }

    @Override
    protected Value computeLockValue(FrameState state, int lockIndex) {
        int lockDepth = lockIndex;
        if (state.outerFrameState() != null) {
            lockDepth += state.outerFrameState().nestedLockDepth();
        }
        StackSlotValue slot = lockStack.makeLockSlot(lockDepth);
        ValueNode lock = state.lockAt(lockIndex);
        Value object = toValue(lock);
        boolean eliminated = object instanceof VirtualObject || state.monitorIdAt(lockIndex) == null;
        assert state.monitorIdAt(lockIndex) == null || state.monitorIdAt(lockIndex).getLockDepth() == lockDepth;
        return new StackLockValue(object, slot, eliminated);
    }

    @Override
    protected BytecodeFrame computeFrameForState(FrameState state) {
        if (isPlaceholderBci(state.bci) && state.bci != BytecodeFrame.BEFORE_BCI) {
            // This is really a hard error since an incorrect state could crash hotspot
            throw JVMCIError.shouldNotReachHere("Invalid state " + BytecodeFrame.getPlaceholderBciName(state.bci) + " " + state);
        }
        return super.computeFrameForState(state);
    }
}