summaryrefslogtreecommitdiff
path: root/compilerplugins/clang/mergeclasses.cxx
blob: bac4a36df1d81c8483c02eabc50fb488b42785b1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

#include <cassert>
#include <set>
#include <string>
#include <iostream>
#include "plugin.hxx"
#include <fstream>

/**

Idea from Norbert (shm_get) - look for classes that are
(a) not instantiated
(b) have zero or one subclasses
and warn about them - would allow us to remove a bunch of abstract classes
that can be merged into one class and simplified.

Dump a list of
- unique classes that exist (A)
- unique classes that are instantiated (B)
- unique class-subclass relationships (C)
Then
   let D = A minus B
   for each class in D, look in C and count the entries, then dump it if no-entries == 1

The process goes something like this:
  $ make check
  $ make FORCE_COMPILE_ALL=1 COMPILER_PLUGIN_TOOL='mergeclasses' check
  $ ./compilerplugins/clang/mergeclasses.py

FIXME exclude 'static-only' classes, which some people may use/have used instead of a namespace to tie together a bunch of functions

*/

namespace {

// try to limit the voluminous output a little
static std::set<std::string> instantiatedSet;
static std::set<std::pair<std::string,std::string> > childToParentClassSet; // childClassName -> parentClassName
static std::map<std::string,std::string> definitionMap;  // className -> filename

class MergeClasses:
    public loplugin::FilteringPlugin<MergeClasses>
{
public:
    explicit MergeClasses(loplugin::InstantiationData const & data):
        FilteringPlugin(data) {}

    virtual void run() override
    {
        TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());

        // dump all our output in one write call - this is to try and limit IO "crosstalk" between multiple processes
        // writing to the same logfile
        std::string output;
        for (const std::string & s : instantiatedSet)
            output += "instantiated:\t" + s + "\n";
        for (const std::pair<std::string,std::string> & s : childToParentClassSet)
            output += "has-subclass:\t" + s.first + "\t" + s.second + "\n";
        for (const std::pair<std::string,std::string> & s : definitionMap)
            output += "definition:\t" + s.first + "\t" + s.second + "\n";
        std::ofstream myfile;
        myfile.open( WORKDIR "/loplugin.mergeclasses.log", std::ios::app | std::ios::out);
        myfile << output;
        myfile.close();
    }

    bool shouldVisitTemplateInstantiations () const { return true; }

    bool VisitVarDecl(const VarDecl *);
    bool VisitFieldDecl(const FieldDecl *);
    bool VisitCXXConstructExpr( const CXXConstructExpr* var );
    bool VisitCXXRecordDecl( const CXXRecordDecl* decl);
};

bool startsWith(const std::string& rStr, const char* pSubStr) {
    return rStr.compare(0, strlen(pSubStr), pSubStr) == 0;
}

bool ignoreClass(StringRef s)
{
    // ignore stuff in the standard library, and UNO stuff we can't touch.
    if (startsWith(s, "rtl::") || startsWith(s, "sal::") || startsWith(s, "com::sun::")
        || startsWith(s, "std::") || startsWith(s, "boost::")
        || s == "OString" || s == "OUString" || s == "bad_alloc")
    {
        return true;
    }
    // ignore instantiations of pointers and arrays
    if (s.endswith("*") || s.endswith("]")) {
        return true;
    }
    return false;
}

// check for implicit construction
bool MergeClasses::VisitVarDecl( const VarDecl* pVarDecl )
{
    if (ignoreLocation(pVarDecl)) {
        return true;
    }
    std::string s = pVarDecl->getType().getAsString();
    if (!ignoreClass(s))
        instantiatedSet.insert(s);
    return true;
}

// check for implicit construction
bool MergeClasses::VisitFieldDecl( const FieldDecl* pFieldDecl )
{
    if (ignoreLocation(pFieldDecl)) {
        return true;
    }
    std::string s = pFieldDecl->getType().getAsString();
    if (!ignoreClass(s))
        instantiatedSet.insert(s);
    return true;
}

bool MergeClasses::VisitCXXConstructExpr( const CXXConstructExpr* pCXXConstructExpr )
{
    if (ignoreLocation(pCXXConstructExpr)) {
        return true;
    }
    // ignore calls when a sub-class is constructing its superclass
    if (pCXXConstructExpr->getConstructionKind() != CXXConstructExpr::ConstructionKind::CK_Complete) {
        return true;
    }
    const CXXConstructorDecl* pCXXConstructorDecl = pCXXConstructExpr->getConstructor();
    const CXXRecordDecl* pParentCXXRecordDecl = pCXXConstructorDecl->getParent();
    std::string s = pParentCXXRecordDecl->getQualifiedNameAsString();
    if (!ignoreClass(s))
        instantiatedSet.insert(s);
    return true;
}

bool MergeClasses::VisitCXXRecordDecl(const CXXRecordDecl* decl)
{
    if (ignoreLocation(decl)) {
        return true;
    }
    if (decl->isThisDeclarationADefinition())
    {
        SourceLocation spellingLocation = compiler.getSourceManager().getSpellingLoc(compat::getBeginLoc(decl));
        std::string filename = compiler.getSourceManager().getFilename(spellingLocation);
        filename = filename.substr(strlen(SRCDIR));
        std::string s = decl->getQualifiedNameAsString();
        if (ignoreClass(s))
            return true;
        definitionMap.insert( std::pair<std::string,std::string>(s, filename) );
        for (auto it = decl->bases_begin(); it != decl->bases_end(); ++it)
        {
            const CXXBaseSpecifier spec = *it;
            // need to look through typedefs, hence the getUnqualifiedDesugaredType
            QualType baseType = spec.getType().getDesugaredType(compiler.getASTContext());
            childToParentClassSet.insert( std::pair<std::string,std::string>(s, baseType.getAsString()) );
        }
    }
    return true;
}

loplugin::Plugin::Registration< MergeClasses > X("mergeclasses", false);

}

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */