/*

 * Copyright (c) 2009, 2015, 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.sun.hotspot.tools.compiler;

import java.io.PrintStream;

import java.util.ArrayDeque;

import java.util.ArrayList;

import java.util.List;

/**

 * Representation of a compilation scope in a compilation log. This class is a

 * hybrid: its instances can represent original scopes of methods being

 * compiled, but are also used to represent call sites in given methods.

 */

public class CallSite {

    /**

     * The index of the call in the caller. This will be 0 if this instance

     * represents a compilation root.

     */

    private int bci;

    /**

     * The method that is called at this call site. This will be {@code null}

     * if this instance represents a compilation root.

     */

    private Method method;

    /**

     * The invocation count for this call site.

     */

    private int count;

    /**

     * The receiver type of the call represented by this instance, if known.

     */

    private String receiver;

    /**

     * In case the {@linkplain receiver receiver type} of the call represented

     * by this instance is known, this is how often the type was encountered.

     */

    private int receiver_count;

    /**

     * The reason for a success or failure of an inlining operation at this

     * call site.

     */

    private String reason;

    /**

     * A list of all calls in this compilation scope.

     */

    private List<CallSite> calls;

    /**

     * Number of nodes in the graph at the end of parsing this compilation

     * scope.

     */

    private int endNodes;

    /**

     * Number of live nodes in the graph at the end of parsing this compilation

     * scope.

     */

    private int endLiveNodes;

    /**

     * Time in seconds since VM startup at which parsing this compilation scope

     * ended.

     */

    private double timeStamp;

    /**

     * The inline ID in case the call represented by this instance is inlined,

     * 0 otherwise.

     */

    private long inlineId;

    /**

     * List of uncommon traps in this compilation scope.

     */

    private List<UncommonTrap> traps;

    /**

     * Default constructor: used to create an instance that represents the top

     * scope of a compilation.

     */

    CallSite() {}

    /**

     * Constructor to create an instance that represents an actual method call.

     */

    CallSite(int bci, Method m) {

        this.bci = bci;

        this.method = m;

    }

    /**

     * Add a call site to the compilation scope represented by this instance.

     */

    void add(CallSite site) {

        if (getCalls() == null) {

            calls = new ArrayList<>();

        }

        getCalls().add(site);

    }

    /**

     * Return the last of the {@linkplain #getCalls() call sites} in this

     * compilation scope.

     */

    CallSite last() {

        return getCalls().get(getCalls().size() - 1);

    }

    /**

     * Return the last-but-one of the {@linkplain #getCalls() call sites} in

     * this compilation scope.

     */

    CallSite lastButOne() {

        return getCalls().get(getCalls().size() - 2);

    }

    public String toString() {

        StringBuilder sb = new StringBuilder();

        if (getReason() == null) {

            sb.append("  @ " + getBci() + " " + getMethod());

        } else {

            sb.append("- @ " + getBci() + " " + getMethod() + " " + getReason());

        }

        sb.append("\n");

        if (getCalls() != null) {

            for (CallSite site : getCalls()) {

                sb.append(site);

                sb.append("\n");

            }

        }

        return sb.toString();

    }

    public void print(PrintStream stream) {

        print(stream, 0, true, false);

    }

    void emit(PrintStream stream, int indent) {

        for (int i = 0; i < indent; i++) {

            stream.print(' ');

        }

    }

    public void print(PrintStream stream, int indent, boolean printInlining, boolean printUncommonTraps) {

        emit(stream, indent);

        String m = getMethod().getHolder() + "::" + getMethod().getName();

        if (getReason() == null) {

            stream.print("  @ " + getBci() + " " + m + " (" + getMethod().getBytes() + " bytes)");

        } else {

            stream.print("  @ " + getBci() + " " + m + " " + getReason());

        }

        stream.printf(" (end time: %6.4f", getTimeStamp());

        if (getEndNodes() > 0) {

            stream.printf(" nodes: %d live: %d", getEndNodes(), getEndLiveNodes());

        }

        stream.println(")");

        if (getReceiver() != null) {

            emit(stream, indent + 4);

            stream.println("type profile " + getMethod().getHolder() + " -> " + getReceiver() + " (" +

                    (getReceiverCount() * 100 / getCount()) + "%)");

        }

        if (printInlining && getCalls() != null) {

            for (CallSite site : getCalls()) {

                site.print(stream, indent + 2, printInlining, printUncommonTraps);

            }

        }

        if (printUncommonTraps && getTraps() != null) {

            for (UncommonTrap site : getTraps()) {

                site.print(stream, indent + 2);

            }

        }

    }

    public int getBci() {

        return bci;

    }

    public void setBci(int bci) {

        this.bci = bci;

    }

    public Method getMethod() {

        return method;

    }

    public void setMethod(Method method) {

        this.method = method;

    }

    public int getCount() {

        return count;

    }

    public void setCount(int count) {

        this.count = count;

    }

    public String getReceiver() {

        return receiver;

    }

    public void setReceiver(String receiver) {

        this.receiver = receiver;

    }

    public int getReceiverCount() {

        return receiver_count;

    }

    public void setReceiver_count(int receiver_count) {

        this.receiver_count = receiver_count;

    }

    public String getReason() {

        return reason;

    }

    public void setReason(String reason) {

        this.reason = reason;

    }

    public List<CallSite> getCalls() {

        return calls;

    }

    public List<UncommonTrap> getTraps() {

        return traps;

    }

    void add(UncommonTrap e) {

        if (traps == null) {

            traps = new ArrayList<UncommonTrap>();

        }

        traps.add(e);

    }

    void setEndNodes(int n) {

        endNodes = n;

    }

    public int getEndNodes() {

        return endNodes;

    }

    void setEndLiveNodes(int n) {

        endLiveNodes = n;

    }

    public int getEndLiveNodes() {

        return endLiveNodes;

    }

    void setTimeStamp(double time) {

        timeStamp = time;

    }

    public double getTimeStamp() {

        return timeStamp;

    }

    /**

     * Check whether this call site matches another. Every late inline call

     * site has a unique inline ID. If the call site we're looking for has one,

     * then use it; otherwise rely on method name and byte code index.

     */

    private boolean matches(CallSite other) {

        if (other.inlineId != 0) {

            return inlineId == other.inlineId;

        }

        return method.equals(other.method) && bci == other.bci;

    }

    /**

     * Locate a late inline call site: find, in this instance's

     * {@linkplain #calls call sites}, the one furthest down the given call

     * stack.

     *

     * Multiple chains of identical call sites with the same method name / bci

     * combination are possible, so we have to try them all until we find the

     * late inline call site that has a matching inline ID.

     *

     * @return a matching call site, or {@code null} if none was found.

     */

    public CallSite findCallSite(ArrayDeque<CallSite> sites) {

        if (calls == null) {

            return null;

        }

        CallSite site = sites.pop();

        for (CallSite c : calls) {

            if (c.matches(site)) {

                if (!sites.isEmpty()) {

                    CallSite res = c.findCallSite(sites);

                    if (res != null) {

                        sites.push(site);

                        return res;

                    }

                } else {

                    sites.push(site);

                    return c;

                }

            }

        }

        sites.push(site);

        return null;

    }

    /**

     * Locate a late inline call site in the tree spanned by all this instance's

     * {@linkplain #calls call sites}, and return the sequence of call sites

     * (scopes) leading to that late inline call site.

     */

    public ArrayDeque<CallSite> findCallSite2(CallSite site) {

        if (calls == null) {

            return null;

        }

        for (CallSite c : calls) {

            if (c.matches(site)) {

                ArrayDeque<CallSite> stack = new ArrayDeque<>();

                stack.push(c);

                return stack;

            } else {

                ArrayDeque<CallSite> stack = c.findCallSite2(site);

                if (stack != null) {

                    stack.push(c);

                    return stack;

                }

            }

        }

        return null;

    }

    public long getInlineId() {

        return inlineId;

    }

    public void setInlineId(long inlineId) {

        this.inlineId = inlineId;

    }

}