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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 05:54:39 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 05:54:39 +0000
commit267c6f2ac71f92999e969232431ba04678e7437e (patch)
tree358c9467650e1d0a1d7227a21dac2e3d08b622b2 /compilerplugins/clang/unusedmethods.cxx
parentInitial commit. (diff)
downloadlibreoffice-267c6f2ac71f92999e969232431ba04678e7437e.tar.xz
libreoffice-267c6f2ac71f92999e969232431ba04678e7437e.zip
Adding upstream version 4:24.2.0.upstream/4%24.2.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--compilerplugins/clang/unusedmethods.cxx429
1 files changed, 429 insertions, 0 deletions
diff --git a/compilerplugins/clang/unusedmethods.cxx b/compilerplugins/clang/unusedmethods.cxx
new file mode 100644
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+++ b/compilerplugins/clang/unusedmethods.cxx
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+/* -*- 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 <string>
+#include <iostream>
+#include <fstream>
+#include <set>
+#include <unordered_map>
+
+
+#include "clang/AST/Attr.h"
+
+#include "config_clang.h"
+
+#include "plugin.hxx"
+
+/**
+This plugin performs 3 different analyses:
+
+(1) Find unused methods
+(2) Find methods whose return types are never evaluated
+(3) Find methods which are public, but are never called from outside the class i.e. they can be private
+
+It does so, by dumping various call/definition/use info to a log file.
+Then we will post-process the various lists and find the set of unused methods.
+
+Be warned that it produces around 15G of log file.
+
+The process goes something like this:
+ $ make check
+ $ make FORCE_COMPILE=all COMPILER_PLUGIN_TOOL='unusedmethods' check
+ $ ./compilerplugins/clang/unusedmethods.py
+
+and then
+ $ for dir in *; do make FORCE_COMPILE=all UPDATE_FILES=$dir COMPILER_PLUGIN_TOOL='unusedmethodsremove' $dir; done
+to auto-remove the method declarations
+
+Note that the actual process may involve a fair amount of undoing, hand editing, and general messing around
+to get it to work :-)
+
+*/
+
+namespace {
+
+struct MyFuncInfo
+{
+ std::string access;
+ std::string returnType;
+ std::string nameAndParams;
+ std::string sourceLocation;
+ std::string virtualness;
+
+};
+bool operator < (const MyFuncInfo &lhs, const MyFuncInfo &rhs)
+{
+ return std::tie(lhs.returnType, lhs.nameAndParams)
+ < std::tie(rhs.returnType, rhs.nameAndParams);
+}
+
+// try to limit the voluminous output a little
+
+// for the "unused method" analysis
+static std::set<MyFuncInfo> callSet;
+static std::set<MyFuncInfo> definitionSet;
+// for the "unused return type" analysis
+static std::set<MyFuncInfo> usedReturnSet;
+// for the "can be private" analysis
+static std::set<MyFuncInfo> calledFromOutsideSet;
+
+
+class UnusedMethods:
+ public RecursiveASTVisitor<UnusedMethods>, public loplugin::Plugin
+{
+public:
+ explicit UnusedMethods(loplugin::InstantiationData const & data):
+ Plugin(data) {}
+
+ virtual void run() override
+ {
+ handler.enableTreeWideAnalysisMode();
+
+ StringRef fn(handler.getMainFileName());
+ // ignore external code, makes this run faster
+ if (fn.contains("UnpackedTarball"))
+ return;
+
+ 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 MyFuncInfo & s : definitionSet)
+ {
+ output += "definition:\t" + s.access + "\t" + s.returnType + "\t" + s.nameAndParams
+ + "\t" + s.sourceLocation + "\t" + s.virtualness + "\n";
+ }
+ // for the "unused method" analysis
+ for (const MyFuncInfo & s : callSet)
+ output += "call:\t" + s.returnType + "\t" + s.nameAndParams + "\n";
+ // for the "unused return type" analysis
+ for (const MyFuncInfo & s : usedReturnSet)
+ output += "usedReturn:\t" + s.returnType + "\t" + s.nameAndParams + "\n";
+ // for the "method can be private" analysis
+ for (const MyFuncInfo & s : calledFromOutsideSet)
+ output += "outside:\t" + s.returnType + "\t" + s.nameAndParams + "\n";
+ std::ofstream myfile;
+ myfile.open( WORKDIR "/loplugin.unusedmethods.log", std::ios::app | std::ios::out);
+ myfile << output;
+ myfile.close();
+ }
+
+ bool shouldVisitTemplateInstantiations () const { return true; }
+ bool shouldVisitImplicitCode() const { return true; }
+
+ bool VisitCallExpr(CallExpr* );
+ bool VisitFunctionDecl( const FunctionDecl* decl );
+ bool VisitDeclRefExpr( const DeclRefExpr* );
+ bool VisitCXXConstructExpr( const CXXConstructExpr* );
+ bool TraverseCXXRecordDecl( CXXRecordDecl* );
+ bool TraverseFunctionDecl( FunctionDecl* );
+ bool TraverseCXXMethodDecl( CXXMethodDecl* );
+ bool TraverseCXXConversionDecl( CXXConversionDecl* );
+ bool TraverseCXXDeductionGuideDecl( CXXDeductionGuideDecl* );
+
+private:
+ void logCallToRootMethods(const FunctionDecl* functionDecl, std::set<MyFuncInfo>& funcSet);
+ MyFuncInfo niceName(const FunctionDecl* functionDecl);
+ std::string toString(SourceLocation loc);
+ void functionTouchedFromExpr( const FunctionDecl* calleeFunctionDecl, const Expr* expr );
+
+ CXXRecordDecl const * currentCxxRecordDecl = nullptr;
+ FunctionDecl const * currentFunctionDecl = nullptr;
+};
+
+MyFuncInfo UnusedMethods::niceName(const FunctionDecl* functionDecl)
+{
+ for(;;)
+ {
+ if (functionDecl->getInstantiatedFromMemberFunction())
+ functionDecl = functionDecl->getInstantiatedFromMemberFunction();
+ else if (functionDecl->getTemplateInstantiationPattern())
+ functionDecl = functionDecl->getTemplateInstantiationPattern();
+ else
+ break;
+ }
+
+ MyFuncInfo aInfo;
+ switch (functionDecl->getAccess())
+ {
+ case AS_public: aInfo.access = "public"; break;
+ case AS_private: aInfo.access = "private"; break;
+ case AS_protected: aInfo.access = "protected"; break;
+ default: aInfo.access = "unknown"; break;
+ }
+ if (!isa<CXXConstructorDecl>(functionDecl)) {
+ aInfo.returnType = functionDecl->getReturnType().getCanonicalType().getAsString();
+ } else {
+ aInfo.returnType = "";
+ }
+
+ if (auto methodDecl = dyn_cast<CXXMethodDecl>(functionDecl)) {
+ const CXXRecordDecl* recordDecl = methodDecl->getParent();
+ aInfo.nameAndParams = recordDecl->getQualifiedNameAsString()
+ + "::"
+ + functionDecl->getNameAsString()
+ + "(";
+ if (methodDecl->isVirtual())
+ aInfo.virtualness = "virtual";
+ }
+ else
+ {
+ aInfo.nameAndParams = functionDecl->getQualifiedNameAsString() + "(";
+ }
+ bool bFirst = true;
+ for (const ParmVarDecl *pParmVarDecl : functionDecl->parameters()) {
+ if (bFirst)
+ bFirst = false;
+ else
+ aInfo.nameAndParams += ",";
+ aInfo.nameAndParams += pParmVarDecl->getType().getCanonicalType().getAsString();
+ }
+ aInfo.nameAndParams += ")";
+ if (isa<CXXMethodDecl>(functionDecl) && dyn_cast<CXXMethodDecl>(functionDecl)->isConst()) {
+ aInfo.nameAndParams += " const";
+ }
+
+ aInfo.sourceLocation = toString( functionDecl->getLocation() );
+
+ return aInfo;
+}
+
+std::string UnusedMethods::toString(SourceLocation loc)
+{
+ SourceLocation expansionLoc = compiler.getSourceManager().getExpansionLoc( loc );
+ StringRef name = getFilenameOfLocation(expansionLoc);
+ std::string sourceLocation = std::string(name.substr(strlen(SRCDIR)+1)) + ":" + std::to_string(compiler.getSourceManager().getSpellingLineNumber(expansionLoc));
+ loplugin::normalizeDotDotInFilePath(sourceLocation);
+ return sourceLocation;
+}
+
+// For virtual/overriding methods, we need to pretend we called the root method(s),
+// so that they get marked as used.
+void UnusedMethods::logCallToRootMethods(const FunctionDecl* functionDecl, std::set<MyFuncInfo>& funcSet)
+{
+ functionDecl = functionDecl->getCanonicalDecl();
+ bool bCalledSuperMethod = false;
+ if (isa<CXXMethodDecl>(functionDecl)) {
+ const CXXMethodDecl* methodDecl = dyn_cast<CXXMethodDecl>(functionDecl);
+ for(CXXMethodDecl::method_iterator it = methodDecl->begin_overridden_methods();
+ it != methodDecl->end_overridden_methods(); ++it)
+ {
+ logCallToRootMethods(*it, funcSet);
+ bCalledSuperMethod = true;
+ }
+ }
+ if (!bCalledSuperMethod)
+ {
+ while (functionDecl->getTemplateInstantiationPattern())
+ functionDecl = functionDecl->getTemplateInstantiationPattern();
+ if (functionDecl->getLocation().isValid() && !ignoreLocation( functionDecl->getBeginLoc() )
+ && !functionDecl->isExternC())
+ funcSet.insert(niceName(functionDecl));
+ }
+}
+
+bool UnusedMethods::VisitCallExpr(CallExpr* expr)
+{
+ // Note that I don't ignore ANYTHING here, because I want to get calls to my code that result
+ // from template instantiation deep inside the STL and other external code
+
+ FunctionDecl* calleeFunctionDecl = expr->getDirectCallee();
+ if (calleeFunctionDecl == nullptr) {
+ Expr* callee = expr->getCallee()->IgnoreParenImpCasts();
+ DeclRefExpr* dr = dyn_cast<DeclRefExpr>(callee);
+ if (dr) {
+ calleeFunctionDecl = dyn_cast<FunctionDecl>(dr->getDecl());
+ if (calleeFunctionDecl)
+ goto gotfunc;
+ }
+ return true;
+ }
+
+gotfunc:
+
+
+ if (currentFunctionDecl == calleeFunctionDecl)
+ ; // for "unused method" analysis, ignore recursive calls
+ else if (currentFunctionDecl
+ && currentFunctionDecl->getIdentifier()
+ && currentFunctionDecl->getName() == "Clone"
+ && currentFunctionDecl->getParent() == calleeFunctionDecl->getParent()
+ && isa<CXXConstructorDecl>(calleeFunctionDecl))
+ ; // if we are inside Clone(), ignore calls to the same class's constructor
+ else
+ logCallToRootMethods(calleeFunctionDecl, callSet);
+
+ const Stmt* parent = getParentStmt(expr);
+
+ // Now do the checks necessary for the "can be private" analysis
+ CXXMethodDecl* calleeMethodDecl = dyn_cast<CXXMethodDecl>(calleeFunctionDecl);
+ if (calleeMethodDecl && calleeMethodDecl->getAccess() != AS_private)
+ {
+ const FunctionDecl* parentFunctionOfCallSite = getParentFunctionDecl(expr);
+ if (parentFunctionOfCallSite != calleeFunctionDecl) {
+ if (!parentFunctionOfCallSite || !ignoreLocation(parentFunctionOfCallSite->getBeginLoc())) {
+ calledFromOutsideSet.insert(niceName(calleeFunctionDecl));
+ }
+ }
+ }
+
+ // Now do the checks necessary for the "unused return value" analysis
+ if (calleeFunctionDecl->getReturnType()->isVoidType()) {
+ return true;
+ }
+ if (!parent) {
+ // we will get null parent if it's under a CXXConstructExpr node
+ logCallToRootMethods(calleeFunctionDecl, usedReturnSet);
+ return true;
+ }
+ if (isa<Expr>(parent) || isa<ReturnStmt>(parent) || isa<DeclStmt>(parent)
+ || isa<IfStmt>(parent) || isa<SwitchStmt>(parent) || isa<ForStmt>(parent)
+ || isa<WhileStmt>(parent) || isa<DoStmt>(parent)
+ || isa<CXXForRangeStmt>(parent))
+ {
+ logCallToRootMethods(calleeFunctionDecl, usedReturnSet);
+ return true;
+ }
+ if (isa<CompoundStmt>(parent) || isa<DefaultStmt>(parent) || isa<CaseStmt>(parent)
+ || isa<LabelStmt>(parent))
+ {
+ return true;
+ }
+ parent->dump();
+ return true;
+}
+
+bool UnusedMethods::VisitCXXConstructExpr( const CXXConstructExpr* constructExpr )
+{
+ // Note that I don't ignore ANYTHING here, because I want to get calls to my code that result
+ // from template instantiation deep inside the STL and other external code
+
+ const CXXConstructorDecl* constructorDecl = constructExpr->getConstructor();
+ constructorDecl = constructorDecl->getCanonicalDecl();
+
+ if (!constructorDecl->getLocation().isValid() || ignoreLocation(constructorDecl->getBeginLoc())) {
+ return true;
+ }
+
+ logCallToRootMethods(constructorDecl, callSet);
+
+ // Now do the checks necessary for the "can be private" analysis
+ if (constructorDecl->getParent() != currentCxxRecordDecl)
+ calledFromOutsideSet.insert(niceName(constructorDecl));
+
+ return true;
+}
+
+bool UnusedMethods::VisitFunctionDecl( const FunctionDecl* functionDecl )
+{
+ // ignore stuff that forms part of the stable URE interface
+ if (isInUnoIncludeFile(functionDecl)) {
+ return true;
+ }
+ const FunctionDecl* canonicalFunctionDecl = functionDecl->getCanonicalDecl();
+ if (isa<CXXDestructorDecl>(functionDecl)) {
+ return true;
+ }
+ if (functionDecl->isDeleted() || functionDecl->isDefaulted()) {
+ return true;
+ }
+ if (isa<CXXConstructorDecl>(functionDecl)
+ && dyn_cast<CXXConstructorDecl>(functionDecl)->isCopyOrMoveConstructor())
+ {
+ return true;
+ }
+ if (!canonicalFunctionDecl->getLocation().isValid() || ignoreLocation(canonicalFunctionDecl->getBeginLoc())) {
+ return true;
+ }
+ // ignore method overrides, since the call will show up as being directed to the root method
+ const CXXMethodDecl* methodDecl = dyn_cast<CXXMethodDecl>(functionDecl);
+ if (methodDecl && (methodDecl->size_overridden_methods() != 0 || methodDecl->hasAttr<OverrideAttr>())) {
+ return true;
+ }
+ if (!functionDecl->isExternC()) {
+ MyFuncInfo funcInfo = niceName(canonicalFunctionDecl);
+ definitionSet.insert(funcInfo);
+ }
+ return true;
+}
+
+bool UnusedMethods::VisitDeclRefExpr( const DeclRefExpr* declRefExpr )
+{
+ const FunctionDecl* functionDecl = dyn_cast<FunctionDecl>(declRefExpr->getDecl());
+ if (!functionDecl) {
+ return true;
+ }
+ logCallToRootMethods(functionDecl->getCanonicalDecl(), callSet);
+ logCallToRootMethods(functionDecl->getCanonicalDecl(), usedReturnSet);
+
+ // Now do the checks necessary for the "can be private" analysis
+ const CXXMethodDecl* methodDecl = dyn_cast<CXXMethodDecl>(functionDecl);
+ if (methodDecl && methodDecl->getAccess() != AS_private)
+ {
+ const FunctionDecl* parentFunctionOfCallSite = getParentFunctionDecl(declRefExpr);
+ if (parentFunctionOfCallSite != functionDecl) {
+ if (!parentFunctionOfCallSite || !ignoreLocation(parentFunctionOfCallSite->getBeginLoc())) {
+ calledFromOutsideSet.insert(niceName(functionDecl));
+ }
+ }
+ }
+
+ return true;
+}
+
+bool UnusedMethods::TraverseCXXRecordDecl(CXXRecordDecl* cxxRecordDecl)
+{
+ auto copy = currentCxxRecordDecl;
+ currentCxxRecordDecl = cxxRecordDecl;
+ bool ret = RecursiveASTVisitor::TraverseCXXRecordDecl(cxxRecordDecl);
+ currentCxxRecordDecl = copy;
+ return ret;
+}
+
+bool UnusedMethods::TraverseFunctionDecl(FunctionDecl* f)
+{
+ auto copy = currentFunctionDecl;
+ currentFunctionDecl = f;
+ bool ret = RecursiveASTVisitor::TraverseFunctionDecl(f);
+ currentFunctionDecl = copy;
+ return ret;
+}
+bool UnusedMethods::TraverseCXXMethodDecl(CXXMethodDecl* f)
+{
+ auto copy = currentFunctionDecl;
+ currentFunctionDecl = f;
+ bool ret = RecursiveASTVisitor::TraverseCXXMethodDecl(f);
+ currentFunctionDecl = copy;
+ return ret;
+}
+bool UnusedMethods::TraverseCXXConversionDecl(CXXConversionDecl* f)
+{
+ auto copy = currentFunctionDecl;
+ currentFunctionDecl = f;
+ bool ret = RecursiveASTVisitor::TraverseCXXConversionDecl(f);
+ currentFunctionDecl = copy;
+ return ret;
+}
+bool UnusedMethods::TraverseCXXDeductionGuideDecl(CXXDeductionGuideDecl* f)
+{
+ auto copy = currentFunctionDecl;
+ currentFunctionDecl = f;
+ bool ret = RecursiveASTVisitor::TraverseCXXDeductionGuideDecl(f);
+ currentFunctionDecl = copy;
+ return ret;
+}
+
+loplugin::Plugin::Registration< UnusedMethods > X("unusedmethods", false);
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */