Adding upstream version 4:24.2.0.upstream/4%24.2.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 548 insertions, 0 deletions

diff --git a/compilerplugins/clang/referencecasting.cxx b/compilerplugins/clang/referencecasting.cxx
new file mode 100644
index 0000000000..cff5b050ea
--- /dev/null
+++ b/compilerplugins/clang/referencecasting.cxx
@@ -0,0 +1,548 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * Based on LLVM/Clang.
+ *
+ * This file is distributed under the University of Illinois Open Source
+ * License. See LICENSE.TXT for details.
+ *
+ */
+#ifndef LO_CLANG_SHARED_PLUGINS
+
+#include "plugin.hxx"
+#include "check.hxx"
+#include "config_clang.h"
+#include <iostream>
+
+/*
+This is a compile-time checker.
+
+Check for cases where we have
+ - two IDL interfaces A and B,
+ - B extends A
+ - we are converting a Reference<B> to a Reference<A> using UNO_QUERY
+
+This makes the code simpler and cheaper, because UNO_QUERY can be surprisingly expensive if used a lot.
+
+*/
+
+namespace
+{
+class ReferenceCasting : public loplugin::FilteringPlugin<ReferenceCasting>
+{
+public:
+    explicit ReferenceCasting(loplugin::InstantiationData const& data)
+        : FilteringPlugin(data)
+    {
+    }
+
+    bool preRun() override
+    {
+        std::string fn(handler.getMainFileName());
+        loplugin::normalizeDotDotInFilePath(fn);
+        // macros
+        if (fn == SRCDIR "/dbaccess/source/ui/browser/formadapter.cxx")
+            return false;
+        // UNO aggregation
+        if (fn == SRCDIR "/toolkit/source/controls/stdtabcontroller.cxx")
+            return false;
+        return true;
+    }
+
+    void run() override
+    {
+        if (preRun())
+        {
+            TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
+        }
+    }
+
+    bool VisitCXXConstructExpr(const CXXConstructExpr* cce);
+    bool VisitCXXMemberCallExpr(const CXXMemberCallExpr* mce);
+    bool VisitCallExpr(const CallExpr*);
+    bool VisitInitListExpr(const InitListExpr*);
+
+private:
+    bool CheckForUnnecessaryGet(const Expr*, bool includeRtlReference);
+};
+
+static const RecordType* extractTemplateType(QualType);
+static bool isDerivedFrom(const CXXRecordDecl* subtypeRecord, const CXXRecordDecl* baseRecord);
+
+bool ReferenceCasting::VisitInitListExpr(const InitListExpr* ile)
+{
+    if (ignoreLocation(ile))
+        return true;
+    for (const Expr* expr : ile->inits())
+    {
+        if (CheckForUnnecessaryGet(expr, /*includeRtlReference*/ true))
+        {
+            report(DiagnosticsEngine::Warning, "unnecessary get() call", expr->getBeginLoc())
+                << expr->getSourceRange();
+            return true;
+        }
+    }
+    return true;
+}
+bool ReferenceCasting::VisitCXXConstructExpr(const CXXConstructExpr* cce)
+{
+    if (ignoreLocation(cce))
+        return true;
+    // don't bother processing anything in the Reference.h file. Makes my life easier when debugging this.
+    StringRef aFileName
+        = getFilenameOfLocation(compiler.getSourceManager().getSpellingLoc(cce->getBeginLoc()));
+    if (loplugin::isSamePathname(aFileName, SRCDIR "/include/com/sun/star/uno/Reference.h"))
+        return true;
+    if (loplugin::isSamePathname(aFileName, SRCDIR "/include/com/sun/star/uno/Reference.hxx"))
+        return true;
+
+    if (cce->getNumArgs() == 0)
+        return true;
+
+    // look for calls to the Reference<T>(x, UNO_something) constructor
+    auto constructorClass = cce->getConstructor()->getParent();
+    auto dc = loplugin::DeclCheck(constructorClass);
+    bool isUnoReference(dc.Class("Reference").Namespace("uno"));
+    bool isRtlReference(dc.Class("Reference").Namespace("rtl").GlobalNamespace());
+    if (!isUnoReference && !isRtlReference)
+        return true;
+
+    if (isUnoReference)
+        if (CheckForUnnecessaryGet(cce->getArg(0), /*includeRtlReference*/ cce->getNumArgs() == 1))
+        {
+            report(DiagnosticsEngine::Warning, "unnecessary get() call",
+                   cce->getArg(0)->getBeginLoc())
+                << cce->getArg(0)->getSourceRange();
+            return true;
+        }
+    if (isRtlReference && cce->getNumArgs() == 1)
+        if (CheckForUnnecessaryGet(cce->getArg(0), /*includeRtlReference*/ true))
+        {
+            report(DiagnosticsEngine::Warning, "unnecessary get() call",
+                   cce->getArg(0)->getBeginLoc())
+                << cce->getArg(0)->getSourceRange();
+            return true;
+        }
+
+    if (isRtlReference)
+        return true;
+    if (isUnoReference && cce->getNumArgs() != 2)
+        return true;
+
+    // ignore the up-casting constructor, which has a std::enable_if second parameter
+    if (isUnoReference && cce->getNumArgs() == 2
+        && !cce->getConstructor()->getParamDecl(1)->getType()->isEnumeralType())
+        return true;
+
+    // extract the type parameter passed to the template
+    const RecordType* templateParamType = extractTemplateType(cce->getType());
+    if (!templateParamType)
+        return true;
+
+    // extract the type of the first parameter passed to the constructor
+    const Expr* constructorArg0 = cce->getArg(0);
+    if (!constructorArg0)
+        return true;
+
+    // drill down the expression tree till we hit the bottom, because at the top, the type is BaseReference
+    QualType argType;
+    for (;;)
+    {
+        if (auto castExpr = dyn_cast<CastExpr>(constructorArg0))
+        {
+            constructorArg0 = castExpr->getSubExprAsWritten();
+            continue;
+        }
+        if (auto matTempExpr = dyn_cast<MaterializeTemporaryExpr>(constructorArg0))
+        {
+            constructorArg0 = matTempExpr->getSubExpr();
+            continue;
+        }
+        if (auto bindTempExpr = dyn_cast<CXXBindTemporaryExpr>(constructorArg0))
+        {
+            constructorArg0 = bindTempExpr->getSubExpr();
+            continue;
+        }
+        if (auto tempObjExpr = dyn_cast<CXXTemporaryObjectExpr>(constructorArg0))
+        {
+            constructorArg0 = tempObjExpr->getArg(0);
+            continue;
+        }
+        if (auto parenExpr = dyn_cast<ParenExpr>(constructorArg0))
+        {
+            constructorArg0 = parenExpr->getSubExpr();
+            continue;
+        }
+        // for the "uno::Reference<X>(*this, UNO_QUERY)" case
+        if (auto unaryOper = dyn_cast<UnaryOperator>(constructorArg0))
+        {
+            if (unaryOper->getOpcode() == UO_Deref)
+            {
+                constructorArg0 = unaryOper->getSubExpr();
+                continue;
+            }
+        }
+        argType = constructorArg0->getType();
+        break;
+    }
+
+    const RecordType* argTemplateType = extractTemplateType(argType);
+    if (!argTemplateType)
+        return true;
+
+    CXXRecordDecl* templateParamRD = dyn_cast<CXXRecordDecl>(templateParamType->getDecl());
+    CXXRecordDecl* constructorArgRD = dyn_cast<CXXRecordDecl>(argTemplateType->getDecl());
+
+    // querying for XInterface (instead of doing an upcast) has special semantics,
+    // to check for UNO object equivalence.
+    if (templateParamRD->getName() == "XInterface")
+        return true;
+
+    // XShape is used in UNO aggregates in very "entertaining" ways, which means an UNO_QUERY
+    // can return a completely different object, e.g. see SwXShape::queryInterface
+    if (templateParamRD->getName() == "XShape")
+        return true;
+
+    if (cce->getNumArgs() == 2)
+        if (auto declRefExpr = dyn_cast<DeclRefExpr>(cce->getArg(1)))
+        {
+            // no warning expected, used to reject null references
+            if (auto enumConstantDecl = dyn_cast<EnumConstantDecl>(declRefExpr->getDecl()))
+            {
+                if (enumConstantDecl->getName() == "UNO_SET_THROW")
+                    return true;
+                if (enumConstantDecl->getName() == "UNO_QUERY_THROW")
+                    return true;
+                if (enumConstantDecl->getName() == "SAL_NO_ACQUIRE")
+                    return true;
+            }
+        }
+
+    if (constructorArgRD->Equals(templateParamRD)
+        || isDerivedFrom(constructorArgRD, templateParamRD))
+    {
+        report(DiagnosticsEngine::Warning,
+               "the source reference is already a subtype of the destination reference, just use =",
+               cce->getBeginLoc())
+            << cce->getSourceRange();
+    }
+    return true;
+}
+
+bool ReferenceCasting::VisitCXXMemberCallExpr(const CXXMemberCallExpr* mce)
+{
+    if (ignoreLocation(mce))
+        return true;
+    // don't bother processing anything in the Reference.h file. Makes my life easier when debugging this.
+    StringRef aFileName
+        = getFilenameOfLocation(compiler.getSourceManager().getSpellingLoc(mce->getBeginLoc()));
+    if (loplugin::isSamePathname(aFileName, SRCDIR "/include/com/sun/star/uno/Reference.h"))
+        return true;
+    if (loplugin::isSamePathname(aFileName, SRCDIR "/include/com/sun/star/uno/Reference.hxx"))
+        return true;
+
+    if (mce->getNumArgs() == 0)
+        return true;
+
+    // look for calls to the Reference<T>.set(x, UNO_QUERY) constructor
+    auto method = mce->getMethodDecl();
+    if (!method || !method->getIdentifier() || method->getName() != "set")
+        return true;
+
+    auto methodRecordDecl = dyn_cast<ClassTemplateSpecializationDecl>(mce->getRecordDecl());
+    if (!methodRecordDecl || !methodRecordDecl->getIdentifier()
+        || methodRecordDecl->getName() != "Reference")
+        return true;
+
+    if (CheckForUnnecessaryGet(mce->getArg(0), /*includeRtlReference*/ mce->getNumArgs() == 1))
+    {
+        report(DiagnosticsEngine::Warning, "unnecessary get() call", mce->getArg(0)->getBeginLoc())
+            << mce->getArg(0)->getSourceRange();
+        return true;
+    }
+
+    if (mce->getNumArgs() != 2)
+        return true;
+
+    // extract the type parameter passed to the template
+    const RecordType* templateParamType
+        = dyn_cast<RecordType>(methodRecordDecl->getTemplateArgs()[0].getAsType());
+    if (!templateParamType)
+        return true;
+
+    // extract the type of the first parameter passed to the method
+    const Expr* arg0 = mce->getArg(0);
+    if (!arg0)
+        return true;
+
+    // drill down the expression tree till we hit the bottom, because at the top, the type is BaseReference
+    QualType argType;
+    for (;;)
+    {
+        if (auto castExpr = dyn_cast<CastExpr>(arg0))
+        {
+            arg0 = castExpr->getSubExpr();
+            continue;
+        }
+        if (auto matTempExpr = dyn_cast<MaterializeTemporaryExpr>(arg0))
+        {
+            arg0 = matTempExpr->getSubExpr();
+            continue;
+        }
+        if (auto bindTempExpr = dyn_cast<CXXBindTemporaryExpr>(arg0))
+        {
+            arg0 = bindTempExpr->getSubExpr();
+            continue;
+        }
+        if (auto tempObjExpr = dyn_cast<CXXTemporaryObjectExpr>(arg0))
+        {
+            arg0 = tempObjExpr->getArg(0);
+            continue;
+        }
+        if (auto parenExpr = dyn_cast<ParenExpr>(arg0))
+        {
+            arg0 = parenExpr->getSubExpr();
+            continue;
+        }
+        argType = arg0->getType();
+        break;
+    }
+
+    const RecordType* argTemplateType = extractTemplateType(argType);
+    if (!argTemplateType)
+        return true;
+
+    CXXRecordDecl* templateParamRD = dyn_cast<CXXRecordDecl>(templateParamType->getDecl());
+    CXXRecordDecl* methodArgRD = dyn_cast<CXXRecordDecl>(argTemplateType->getDecl());
+
+    // querying for XInterface (instead of doing an upcast) has special semantics,
+    // to check for UNO object equivalence.
+    if (templateParamRD->getName() == "XInterface")
+        return true;
+
+    // XShape is used in UNO aggregates in very "entertaining" ways, which means an UNO_QUERY
+    // can return a completely different object, e.g. see SwXShape::queryInterface
+    if (templateParamRD->getName() == "XShape")
+        return true;
+
+    if (mce->getNumArgs() == 2)
+        if (auto declRefExpr = dyn_cast<DeclRefExpr>(mce->getArg(1)))
+        {
+            // no warning expected, used to reject null references
+            if (auto enumConstantDecl = dyn_cast<EnumConstantDecl>(declRefExpr->getDecl()))
+            {
+                if (enumConstantDecl->getName() == "UNO_SET_THROW")
+                    return true;
+                if (enumConstantDecl->getName() == "UNO_QUERY_THROW")
+                    return true;
+                if (enumConstantDecl->getName() == "SAL_NO_ACQUIRE")
+                    return true;
+            }
+        }
+
+    if (methodArgRD->Equals(templateParamRD) || isDerivedFrom(methodArgRD, templateParamRD))
+    {
+        report(DiagnosticsEngine::Warning,
+               "the source reference is already a subtype of the destination reference, just use =",
+               mce->getBeginLoc())
+            << mce->getSourceRange();
+    }
+    return true;
+}
+
+bool ReferenceCasting::VisitCallExpr(const CallExpr* ce)
+{
+    if (ignoreLocation(ce))
+        return true;
+    // don't bother processing anything in the Reference.h file. Makes my life easier when debugging this.
+    StringRef aFileName
+        = getFilenameOfLocation(compiler.getSourceManager().getSpellingLoc(ce->getBeginLoc()));
+    if (loplugin::isSamePathname(aFileName, SRCDIR "/include/com/sun/star/uno/Reference.h"))
+        return true;
+    if (loplugin::isSamePathname(aFileName, SRCDIR "/include/com/sun/star/uno/Reference.hxx"))
+        return true;
+
+    // look for calls to Reference<T>::query(x)
+    auto method = dyn_cast_or_null<CXXMethodDecl>(ce->getDirectCallee());
+    if (!method || !method->getIdentifier() || method->getName() != "query")
+        return true;
+    if (ce->getNumArgs() != 1)
+        return true;
+
+    auto methodRecordDecl = dyn_cast<ClassTemplateSpecializationDecl>(method->getParent());
+    if (!methodRecordDecl || !methodRecordDecl->getIdentifier()
+        || methodRecordDecl->getName() != "Reference")
+        return true;
+
+    if (CheckForUnnecessaryGet(ce->getArg(0), /*includeRtlReference*/ true))
+        report(DiagnosticsEngine::Warning, "unnecessary get() call", ce->getArg(0)->getBeginLoc())
+            << ce->getArg(0)->getSourceRange();
+
+    // extract the type parameter passed to the template
+    const RecordType* templateParamType
+        = dyn_cast<RecordType>(methodRecordDecl->getTemplateArgs()[0].getAsType());
+    if (!templateParamType)
+        return true;
+
+    // extract the type of the first parameter passed to the method
+    const Expr* arg0 = ce->getArg(0);
+    if (!arg0)
+        return true;
+
+    // drill down the expression tree till we hit the bottom, because at the top, the type is BaseReference
+    QualType argType;
+    for (;;)
+    {
+        if (auto castExpr = dyn_cast<CastExpr>(arg0))
+        {
+            arg0 = castExpr->getSubExpr();
+            continue;
+        }
+        if (auto matTempExpr = dyn_cast<MaterializeTemporaryExpr>(arg0))
+        {
+            arg0 = matTempExpr->getSubExpr();
+            continue;
+        }
+        if (auto bindTempExpr = dyn_cast<CXXBindTemporaryExpr>(arg0))
+        {
+            arg0 = bindTempExpr->getSubExpr();
+            continue;
+        }
+        if (auto tempObjExpr = dyn_cast<CXXTemporaryObjectExpr>(arg0))
+        {
+            arg0 = tempObjExpr->getArg(0);
+            continue;
+        }
+        if (auto parenExpr = dyn_cast<ParenExpr>(arg0))
+        {
+            arg0 = parenExpr->getSubExpr();
+            continue;
+        }
+        argType = arg0->getType();
+        break;
+    }
+
+    const RecordType* argTemplateType = extractTemplateType(argType);
+    if (!argTemplateType)
+        return true;
+
+    CXXRecordDecl* templateParamRD = dyn_cast<CXXRecordDecl>(templateParamType->getDecl());
+    CXXRecordDecl* methodArgRD = dyn_cast<CXXRecordDecl>(argTemplateType->getDecl());
+
+    // querying for XInterface (instead of doing an upcast) has special semantics,
+    // to check for UNO object equivalence.
+    if (templateParamRD->getName() == "XInterface")
+        return true;
+
+    // XShape is used in UNO aggregates in very "entertaining" ways, which means an UNO_QUERY
+    // can return a completely different object, e.g. see SwXShape::queryInterface
+    if (templateParamRD->getName() == "XShape")
+        return true;
+
+    if (methodArgRD->Equals(templateParamRD) || isDerivedFrom(methodArgRD, templateParamRD))
+    {
+        report(DiagnosticsEngine::Warning,
+               "the source reference is already a subtype of the destination reference, just use =",
+               ce->getBeginLoc())
+            << ce->getSourceRange();
+    }
+    return true;
+}
+
+/**
+    Check for
+        Reference<T>(x.get(), UNO_QUERY)
+    because sometimes simplifying that means the main purpose of this plugin can kick in.
+ */
+bool ReferenceCasting::CheckForUnnecessaryGet(const Expr* expr, bool includeRtlReference)
+{
+    expr = expr->IgnoreImplicit();
+    auto cxxMemberCallExpr = dyn_cast<CXXMemberCallExpr>(expr);
+    if (!cxxMemberCallExpr)
+        return false;
+    auto methodDecl = cxxMemberCallExpr->getMethodDecl();
+    if (!methodDecl)
+        return false;
+    if (!methodDecl->getIdentifier() || methodDecl->getName() != "get")
+        return false;
+
+    if (!loplugin::TypeCheck(expr->getType()).Pointer())
+        return false;
+    auto dc = loplugin::DeclCheck(methodDecl->getParent());
+    if (dc.Class("Reference").Namespace("uno"))
+        ; // ok
+    else if (includeRtlReference && dc.Class("Reference").Namespace("rtl"))
+        ; // ok
+    else
+        return false;
+
+    StringRef aFileName
+        = getFilenameOfLocation(compiler.getSourceManager().getSpellingLoc(expr->getBeginLoc()));
+    if (loplugin::isSamePathname(aFileName, SRCDIR "/cppu/qa/test_reference.cxx"))
+        return false;
+
+    return true;
+}
+
+static const RecordType* extractTemplateType(QualType cceType)
+{
+    // check for passing raw pointer to interface case
+    if (cceType->isPointerType())
+    {
+        auto pointeeType = cceType->getPointeeType();
+        if (auto elaboratedType = dyn_cast<ElaboratedType>(pointeeType))
+            pointeeType = elaboratedType->desugar();
+        if (auto substTemplateTypeParmType = dyn_cast<SubstTemplateTypeParmType>(pointeeType))
+            pointeeType = substTemplateTypeParmType->desugar();
+        if (auto recordType = dyn_cast<RecordType>(pointeeType))
+            return recordType;
+    }
+
+    // extract Foo from Reference<Foo>
+    if (auto subst = dyn_cast<SubstTemplateTypeParmType>(cceType))
+    {
+        if (auto recType = dyn_cast<RecordType>(subst->desugar()))
+        {
+            if (auto ctsd = dyn_cast<ClassTemplateSpecializationDecl>(recType->getDecl()))
+            {
+                auto const& args = ctsd->getTemplateArgs();
+                if (args.size() > 0 && args[0].getKind() == TemplateArgument::ArgKind::Type)
+                    return dyn_cast_or_null<RecordType>(args[0].getAsType().getTypePtr());
+            }
+        }
+    }
+
+    if (auto elaboratedType = dyn_cast<ElaboratedType>(cceType))
+        cceType = elaboratedType->desugar();
+    auto cceTST = dyn_cast<TemplateSpecializationType>(cceType);
+    if (!cceTST)
+        return NULL;
+    auto const args = cceTST->template_arguments();
+    if (args.size() != 1)
+        return NULL;
+    const TemplateArgument& cceTA = args[0];
+    QualType templateParamType = cceTA.getAsType();
+    if (auto elaboratedType = dyn_cast<ElaboratedType>(templateParamType))
+        templateParamType = elaboratedType->desugar();
+    return dyn_cast<RecordType>(templateParamType);
+}
+
+/**
+  Implement my own isDerived because we can't always see all the definitions of the classes involved.
+  which will cause an assert with the normal clang isDerivedFrom code.
+*/
+static bool isDerivedFrom(const CXXRecordDecl* subtypeRecord, const CXXRecordDecl* baseRecord)
+{
+    // if there is more than one case, then we have an ambiguous conversion, and we can't change the code
+    // to use the upcasting constructor.
+    return loplugin::derivedFromCount(subtypeRecord, baseRecord) == 1;
+}
+
+loplugin::Plugin::Registration<ReferenceCasting> referencecasting("referencecasting");
+
+} // namespace
+
+#endif // LO_CLANG_SHARED_PLUGINS
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */