1/*
2 * Copyright (C) 2013 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include "config.h"
32#include "core/css/resolver/StyleResolverStats.h"
33
34#include "wtf/text/CString.h"
35#include "wtf/text/StringBuilder.h"
36
37#define PERCENT(x, y) ((!y) ? 0 : (((x) * 100.0) / (y)))
38
39namespace blink {
40
41void StyleResolverStats::reset()
42{
43    sharedStyleLookups = 0;
44    sharedStyleCandidates = 0;
45    sharedStyleFound = 0;
46    sharedStyleMissed = 0;
47    sharedStyleRejectedByUncommonAttributeRules = 0;
48    sharedStyleRejectedBySiblingRules = 0;
49    sharedStyleRejectedByParent = 0;
50    matchedPropertyApply = 0;
51    matchedPropertyCacheHit = 0;
52    matchedPropertyCacheInheritedHit = 0;
53    matchedPropertyCacheAdded = 0;
54}
55
56String StyleResolverStats::report() const
57{
58    StringBuilder output;
59
60    unsigned sharedStylesRejected = sharedStyleRejectedByUncommonAttributeRules + sharedStyleRejectedBySiblingRules + sharedStyleRejectedByParent;
61    unsigned sharedStylesUsed = sharedStyleFound - sharedStylesRejected;
62
63    output.appendLiteral("Style sharing:\n");
64    output.append(String::format("  %u elements were added to the sharing candidate list.\n", sharedStyleCandidates));
65    output.append(String::format("  %u calls were made to findSharedStyle, %u found a candidate to share with (%.2f%%).\n", sharedStyleLookups, sharedStyleFound, PERCENT(sharedStyleFound, sharedStyleLookups)));
66    if (printMissedCandidateCount)
67        output.append(String::format("  %u candidates could have matched but were not in the list when searching (%.2f%%).\n", sharedStyleMissed, PERCENT(sharedStyleMissed, sharedStyleLookups)));
68    output.append(String::format("  %u of found styles were rejected (%.2f%%), %.2f%% by uncommon attribute rules, %.2f%% by sibling rules and %.2f%% by parents disabling sharing.\n",
69        sharedStylesRejected,
70        PERCENT(sharedStylesRejected, sharedStyleFound),
71        PERCENT(sharedStyleRejectedByUncommonAttributeRules, sharedStylesRejected),
72        PERCENT(sharedStyleRejectedBySiblingRules, sharedStylesRejected),
73        PERCENT(sharedStyleRejectedByParent, sharedStylesRejected)));
74    output.append(String::format("  %u of found styles were used for sharing (%.2f%%).\n", sharedStylesUsed, PERCENT(sharedStylesUsed, sharedStyleFound)));
75    output.append(String::format("  %.2f%% of calls to findSharedStyle returned a shared style.\n", PERCENT(sharedStylesUsed, sharedStyleLookups)));
76
77    output.append('\n');
78
79    output.appendLiteral("Matched property cache:\n");
80    output.append(String::format("  %u calls to applyMatchedProperties, %u hit the cache (%.2f%%).\n", matchedPropertyApply, matchedPropertyCacheHit, PERCENT(matchedPropertyCacheHit, matchedPropertyApply)));
81    output.append(String::format("  %u cache hits also shared the inherited style (%.2f%%).\n", matchedPropertyCacheInheritedHit, PERCENT(matchedPropertyCacheInheritedHit, matchedPropertyCacheHit)));
82    output.append(String::format("  %u styles created in applyMatchedProperties were added to the cache (%.2f%%).\n", matchedPropertyCacheAdded, PERCENT(matchedPropertyCacheAdded, matchedPropertyApply)));
83
84    return output.toString();
85}
86
87} // namespace blink
88