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
174
175
|
//===--- FunctionSize.cpp - clang-tidy ------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "FunctionSizeCheck.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
using namespace clang::ast_matchers;
namespace clang {
namespace tidy {
namespace readability {
namespace {
class FunctionASTVisitor : public RecursiveASTVisitor<FunctionASTVisitor> {
using Base = RecursiveASTVisitor<FunctionASTVisitor>;
public:
bool TraverseStmt(Stmt *Node) {
if (!Node)
return Base::TraverseStmt(Node);
if (TrackedParent.back() && !isa<CompoundStmt>(Node))
++Info.Statements;
switch (Node->getStmtClass()) {
case Stmt::IfStmtClass:
case Stmt::WhileStmtClass:
case Stmt::DoStmtClass:
case Stmt::CXXForRangeStmtClass:
case Stmt::ForStmtClass:
case Stmt::SwitchStmtClass:
++Info.Branches;
LLVM_FALLTHROUGH;
case Stmt::CompoundStmtClass:
TrackedParent.push_back(true);
break;
default:
TrackedParent.push_back(false);
break;
}
Base::TraverseStmt(Node);
TrackedParent.pop_back();
return true;
}
bool TraverseCompoundStmt(CompoundStmt *Node) {
// If this new compound statement is located in a compound statement, which
// is already nested NestingThreshold levels deep, record the start location
// of this new compound statement.
if (CurrentNestingLevel == Info.NestingThreshold)
Info.NestingThresholders.push_back(Node->getLocStart());
++CurrentNestingLevel;
Base::TraverseCompoundStmt(Node);
--CurrentNestingLevel;
return true;
}
bool TraverseDecl(Decl *Node) {
TrackedParent.push_back(false);
Base::TraverseDecl(Node);
TrackedParent.pop_back();
return true;
}
struct FunctionInfo {
unsigned Lines = 0;
unsigned Statements = 0;
unsigned Branches = 0;
unsigned NestingThreshold = 0;
std::vector<SourceLocation> NestingThresholders;
};
FunctionInfo Info;
std::vector<bool> TrackedParent;
unsigned CurrentNestingLevel = 0;
};
} // namespace
FunctionSizeCheck::FunctionSizeCheck(StringRef Name, ClangTidyContext *Context)
: ClangTidyCheck(Name, Context),
LineThreshold(Options.get("LineThreshold", -1U)),
StatementThreshold(Options.get("StatementThreshold", 800U)),
BranchThreshold(Options.get("BranchThreshold", -1U)),
ParameterThreshold(Options.get("ParameterThreshold", -1U)),
NestingThreshold(Options.get("NestingThreshold", -1U)) {}
void FunctionSizeCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
Options.store(Opts, "LineThreshold", LineThreshold);
Options.store(Opts, "StatementThreshold", StatementThreshold);
Options.store(Opts, "BranchThreshold", BranchThreshold);
Options.store(Opts, "ParameterThreshold", ParameterThreshold);
Options.store(Opts, "NestingThreshold", NestingThreshold);
}
void FunctionSizeCheck::registerMatchers(MatchFinder *Finder) {
Finder->addMatcher(functionDecl(unless(isInstantiated())).bind("func"), this);
}
void FunctionSizeCheck::check(const MatchFinder::MatchResult &Result) {
const auto *Func = Result.Nodes.getNodeAs<FunctionDecl>("func");
FunctionASTVisitor Visitor;
Visitor.Info.NestingThreshold = NestingThreshold;
Visitor.TraverseDecl(const_cast<FunctionDecl *>(Func));
auto &FI = Visitor.Info;
if (FI.Statements == 0)
return;
// Count the lines including whitespace and comments. Really simple.
if (const Stmt *Body = Func->getBody()) {
SourceManager *SM = Result.SourceManager;
if (SM->isWrittenInSameFile(Body->getLocStart(), Body->getLocEnd())) {
FI.Lines = SM->getSpellingLineNumber(Body->getLocEnd()) -
SM->getSpellingLineNumber(Body->getLocStart());
}
}
unsigned ActualNumberParameters = Func->getNumParams();
if (FI.Lines > LineThreshold || FI.Statements > StatementThreshold ||
FI.Branches > BranchThreshold ||
ActualNumberParameters > ParameterThreshold ||
!FI.NestingThresholders.empty()) {
diag(Func->getLocation(),
"function %0 exceeds recommended size/complexity thresholds")
<< Func;
}
if (FI.Lines > LineThreshold) {
diag(Func->getLocation(),
"%0 lines including whitespace and comments (threshold %1)",
DiagnosticIDs::Note)
<< FI.Lines << LineThreshold;
}
if (FI.Statements > StatementThreshold) {
diag(Func->getLocation(), "%0 statements (threshold %1)",
DiagnosticIDs::Note)
<< FI.Statements << StatementThreshold;
}
if (FI.Branches > BranchThreshold) {
diag(Func->getLocation(), "%0 branches (threshold %1)", DiagnosticIDs::Note)
<< FI.Branches << BranchThreshold;
}
if (ActualNumberParameters > ParameterThreshold) {
diag(Func->getLocation(), "%0 parameters (threshold %1)",
DiagnosticIDs::Note)
<< ActualNumberParameters << ParameterThreshold;
}
for (const auto &CSPos : FI.NestingThresholders) {
diag(CSPos, "nesting level %0 starts here (threshold %1)",
DiagnosticIDs::Note)
<< NestingThreshold + 1 << NestingThreshold;
}
}
} // namespace readability
} // namespace tidy
} // namespace clang
|
