extract some common code for checking if a functions address was taken

Change-Id: I292b4e9bf17c83f83ff43ac4c5870d33092d0c71

1 files changed, 120 insertions, 0 deletions

diff --git a/compilerplugins/clang/functionaddress.hxx b/compilerplugins/clang/functionaddress.hxx
new file mode 100644
index 000000000000..dc34262a50b0
--- /dev/null
+++ b/compilerplugins/clang/functionaddress.hxx
@@ -0,0 +1,120 @@
+/* -*- 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/.
+ */
+
+#ifndef INCLUDED_COMPILERPLUGINS_CLANG_FUNCTIONADDRESS_HXX
+#define INCLUDED_COMPILERPLUGINS_CLANG_FUNCTIONADDRESS_HXX
+
+#include <clang/AST/RecursiveASTVisitor.h>
+#include <unordered_set>
+#include "plugin.hxx"
+
+/**
+ * Common code for checking if the address of a function was taken.
+ */
+namespace loplugin {
+
+template<typename Derived>
+class FunctionAddress : public RecursiveASTVisitor<Derived>, public loplugin::Plugin
+{
+public:
+    explicit FunctionAddress( const InstantiationData& data ) : loplugin::Plugin(data) {}
+
+    bool TraverseCallExpr(CallExpr * expr) {
+        auto const saved = callee_;
+        callee_ = expr->getCallee();
+        auto const ret = RecursiveASTVisitor<Derived>::TraverseCallExpr(expr);
+        callee_ = saved;
+        return ret;
+    }
+
+    bool TraverseCXXOperatorCallExpr(CXXOperatorCallExpr * expr) {
+        auto const saved = callee_;
+        callee_ = expr->getCallee();
+        auto const ret = RecursiveASTVisitor<Derived>::TraverseCXXOperatorCallExpr(expr);
+        callee_ = saved;
+        return ret;
+    }
+
+    bool TraverseCXXMemberCallExpr(CXXMemberCallExpr * expr) {
+        auto const saved = callee_;
+        callee_ = expr->getCallee();
+        auto const ret = RecursiveASTVisitor<Derived>::TraverseCXXMemberCallExpr(expr);
+        callee_ = saved;
+        return ret;
+    }
+
+    bool TraverseCUDAKernelCallExpr(CUDAKernelCallExpr * expr) {
+        auto const saved = callee_;
+        callee_ = expr->getCallee();
+        auto const ret = RecursiveASTVisitor<Derived>::TraverseCUDAKernelCallExpr(expr);
+        callee_ = saved;
+        return ret;
+    }
+
+    bool TraverseUserDefinedLiteral(UserDefinedLiteral * expr) {
+        auto const saved = callee_;
+        callee_ = expr->getCallee();
+        auto const ret = RecursiveASTVisitor<Derived>::TraverseUserDefinedLiteral(expr);
+        callee_ = saved;
+        return ret;
+    }
+
+    bool VisitImplicitCastExpr(ImplicitCastExpr const * expr) {
+        if (expr == callee_) {
+            return true;
+        }
+        if (ignoreLocation(expr)) {
+            return true;
+        }
+        if (expr->getCastKind() != CK_FunctionToPointerDecay) {
+            return true;
+        }
+        auto const dre = dyn_cast<DeclRefExpr>(
+            expr->getSubExpr()->IgnoreParens());
+        if (dre == nullptr) {
+            return true;
+        }
+        auto const fd = dyn_cast<FunctionDecl>(dre->getDecl());
+        if (fd == nullptr) {
+            return true;
+        }
+        ignoredFunctions_.insert(fd->getCanonicalDecl());
+        return true;
+    }
+
+    bool VisitUnaryAddrOf(UnaryOperator const * expr) {
+        if (ignoreLocation(expr)) {
+            return true;
+        }
+        auto const dre = dyn_cast<DeclRefExpr>(
+            expr->getSubExpr()->IgnoreParenImpCasts());
+        if (dre == nullptr) {
+            return true;
+        }
+        auto const fd = dyn_cast<FunctionDecl>(dre->getDecl());
+        if (fd == nullptr) {
+            return true;
+        }
+        ignoredFunctions_.insert(fd->getCanonicalDecl());
+        return true;
+    }
+
+protected:
+    std::unordered_set<FunctionDecl const *> const & getFunctionsWithAddressTaken() { return ignoredFunctions_; }
+
+private:
+    std::unordered_set<FunctionDecl const *> ignoredFunctions_;
+    Expr const * callee_ = nullptr;
+};
+
+}
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */