rewriter for postfix->prefix operator++

Change-Id: I59a7490ec76b10fd31033d1ceccd1e3eae0ad398

compilerplugins/clang/postfixincrementfix.hxx

@@ -0,0 +1,40 @@
+/*
+ * 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 POSTFIXINCREMENTFIX_H
+#define POSTFIXINCREMENTFIX_H
+
+#include "plugin.hxx"
+
+namespace loplugin
+{
+
+class PostfixIncrementFix
+    : public RecursiveASTVisitor< PostfixIncrementFix >
+    , public RewritePlugin
+    {
+    public:
+        explicit PostfixIncrementFix( ASTContext& context, Rewriter& rewriter );
+        void run();
+        bool VisitFunctionDecl( FunctionDecl* declaration );
+    private:
+        typedef std::vector< const Stmt* > StmtParents;
+        void fixPostfixOperator( const CXXOperatorCallExpr* op, StmtParents& parents );
+        void fixPostfixOperators( const Stmt* stmt, StmtParents& parents );
+        bool canChangePostfixToPrefix( const CXXOperatorCallExpr* op, StmtParents& parents, int parent_pos );
+        bool canChangeInConditionStatement( const CXXOperatorCallExpr* op, const Expr* condition,
+            const StmtParents& parents, int parent_pos );
+        bool shouldDoChange( const Expr* op );
+    };
+
+} // namespace
+
+#endif // POSTFIXINCREMENTFIX_H
+