clang 19.0.0git
AnalyzerStatsChecker.cpp
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1//==--AnalyzerStatsChecker.cpp - Analyzer visitation statistics --*- C++ -*-==//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8// This file reports various statistics about analyzer visitation.
9//===----------------------------------------------------------------------===//
10#include "clang/AST/DeclObjC.h"
18#include "llvm/ADT/STLExtras.h"
19#include "llvm/ADT/SmallPtrSet.h"
20#include "llvm/ADT/SmallString.h"
21#include "llvm/ADT/Statistic.h"
22#include "llvm/Support/raw_ostream.h"
23#include <optional>
24
25using namespace clang;
26using namespace ento;
27
28#define DEBUG_TYPE "StatsChecker"
29
30STATISTIC(NumBlocks,
31 "The # of blocks in top level functions");
32STATISTIC(NumBlocksUnreachable,
33 "The # of unreachable blocks in analyzing top level functions");
34
35namespace {
36class AnalyzerStatsChecker : public Checker<check::EndAnalysis> {
37public:
38 void checkEndAnalysis(ExplodedGraph &G, BugReporter &B,ExprEngine &Eng) const;
39};
40}
41
42void AnalyzerStatsChecker::checkEndAnalysis(ExplodedGraph &G,
43 BugReporter &B,
44 ExprEngine &Eng) const {
45 const CFG *C = nullptr;
48
49 // Root node should have the location context of the top most function.
50 const ExplodedNode *GraphRoot = *G.roots_begin();
51 const LocationContext *LC = GraphRoot->getLocation().getLocationContext();
52
53 const Decl *D = LC->getDecl();
54
55 // Iterate over the exploded graph.
56 for (const ExplodedNode &N : G.nodes()) {
57 const ProgramPoint &P = N.getLocation();
58
59 // Only check the coverage in the top level function (optimization).
60 if (D != P.getLocationContext()->getDecl())
61 continue;
62
63 if (std::optional<BlockEntrance> BE = P.getAs<BlockEntrance>()) {
64 const CFGBlock *CB = BE->getBlock();
65 reachable.insert(CB);
66 }
67 }
68
69 // Get the CFG and the Decl of this block.
70 C = LC->getCFG();
71
72 unsigned total = 0, unreachable = 0;
73
74 // Find CFGBlocks that were not covered by any node
75 for (CFG::const_iterator I = C->begin(); I != C->end(); ++I) {
76 const CFGBlock *CB = *I;
77 ++total;
78 // Check if the block is unreachable
79 if (!reachable.count(CB)) {
81 }
82 }
83
84 // We never 'reach' the entry block, so correct the unreachable count
86 // There is no BlockEntrance corresponding to the exit block as well, so
87 // assume it is reached as well.
89
90 // Generate the warning string
92 llvm::raw_svector_ostream output(buf);
93 PresumedLoc Loc = SM.getPresumedLoc(D->getLocation());
94 if (!Loc.isValid())
95 return;
96
97 if (isa<FunctionDecl, ObjCMethodDecl>(D)) {
98 const NamedDecl *ND = cast<NamedDecl>(D);
99 output << *ND;
100 } else if (isa<BlockDecl>(D)) {
101 output << "block(line:" << Loc.getLine() << ":col:" << Loc.getColumn();
102 }
103
104 NumBlocksUnreachable += unreachable;
105 NumBlocks += total;
106 std::string NameOfRootFunction = std::string(output.str());
107
108 output << " -> Total CFGBlocks: " << total << " | Unreachable CFGBlocks: "
109 << unreachable << " | Exhausted Block: "
110 << (Eng.wasBlocksExhausted() ? "yes" : "no")
111 << " | Empty WorkList: "
112 << (Eng.hasEmptyWorkList() ? "yes" : "no");
113
114 B.EmitBasicReport(D, this, "Analyzer Statistics", "Internal Statistics",
115 output.str(), PathDiagnosticLocation(D, SM));
116
117 // Emit warning for each block we bailed out on.
118 const CoreEngine &CE = Eng.getCoreEngine();
119 for (const BlockEdge &BE : make_first_range(CE.exhausted_blocks())) {
120 const CFGBlock *Exit = BE.getDst();
121 if (Exit->empty())
122 continue;
123 const CFGElement &CE = Exit->front();
124 if (std::optional<CFGStmt> CS = CE.getAs<CFGStmt>()) {
125 SmallString<128> bufI;
126 llvm::raw_svector_ostream outputI(bufI);
127 outputI << "(" << NameOfRootFunction << ")" <<
128 ": The analyzer generated a sink at this point";
130 D, this, "Sink Point", "Internal Statistics", outputI.str(),
131 PathDiagnosticLocation::createBegin(CS->getStmt(), SM, LC));
132 }
133 }
134}
135
136void ento::registerAnalyzerStatsChecker(CheckerManager &mgr) {
137 mgr.registerChecker<AnalyzerStatsChecker>();
138}
139
140bool ento::shouldRegisterAnalyzerStatsChecker(const CheckerManager &mgr) {
141 return true;
142}
StringRef P
STATISTIC(NumBlocks, "The # of blocks in top level functions")
#define SM(sm)
Definition: Cuda.cpp:83
const Decl * D
Defines the SourceManager interface.
#define unreachable()
Represents a single basic block in a source-level CFG.
Definition: CFG.h:604
Represents a top-level expression in a basic block.
Definition: CFG.h:55
std::optional< T > getAs() const
Convert to the specified CFGElement type, returning std::nullopt if this CFGElement is not of the des...
Definition: CFG.h:109
Represents a source-level, intra-procedural CFG that represents the control-flow of a Stmt.
Definition: CFG.h:1214
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:86
SourceLocation getLocation() const
Definition: DeclBase.h:445
It wraps the AnalysisDeclContext to represent both the call stack with the help of StackFrameContext ...
const Decl * getDecl() const
This represents a decl that may have a name.
Definition: Decl.h:249
Represents an unpacked "presumed" location which can be presented to the user.
const LocationContext * getLocationContext() const
Definition: ProgramPoint.h:175
This class handles loading and caching of source files into memory.
BugReporter is a utility class for generating PathDiagnostics for analysis.
Definition: BugReporter.h:585
const SourceManager & getSourceManager()
Definition: BugReporter.h:623
void EmitBasicReport(const Decl *DeclWithIssue, const CheckerBase *Checker, StringRef BugName, StringRef BugCategory, StringRef BugStr, PathDiagnosticLocation Loc, ArrayRef< SourceRange > Ranges=std::nullopt, ArrayRef< FixItHint > Fixits=std::nullopt)
CHECKER * registerChecker(AT &&... Args)
Used to register checkers.
CoreEngine - Implements the core logic of the graph-reachability analysis.
Definition: CoreEngine.h:56
auto exhausted_blocks() const
Definition: CoreEngine.h:173
bool isValid() const =delete
llvm::iterator_range< node_iterator > nodes()
roots_iterator roots_begin()
ProgramPoint getLocation() const
getLocation - Returns the edge associated with the given node.
const CoreEngine & getCoreEngine() const
Definition: ExprEngine.h:433
bool hasEmptyWorkList() const
Definition: ExprEngine.h:430
bool wasBlocksExhausted() const
Definition: ExprEngine.h:429
static PathDiagnosticLocation createBegin(const Decl *D, const SourceManager &SM)
Create a location for the beginning of the declaration.
The JSON file list parser is used to communicate input to InstallAPI.