diff --git a/lib/astutils.cpp b/lib/astutils.cpp
index 0ffb97645..293e7b6a1 100644
--- a/lib/astutils.cpp
+++ b/lib/astutils.cpp
@@ -135,16 +135,9 @@ const Token * astIsVariableComparison(const Token *tok, const std::string &comp,
 
 const Token * nextAfterAstRightmostLeaf(const Token * tok)
 {
-    const Token * rightmostLeaf = tok;
-    if (!rightmostLeaf || !rightmostLeaf->astOperand1())
+    if (!tok || !tok->astOperand1())
         return nullptr;
-    do {
-        if (rightmostLeaf->astOperand2())
-            rightmostLeaf = rightmostLeaf->astOperand2();
-        else
-            rightmostLeaf = rightmostLeaf->astOperand1();
-    } while (rightmostLeaf->astOperand1());
-    return rightmostLeaf->next();
+    return tok->findExpressionStartEndTokens().second->next();
 }
 
 static const Token * getVariableInitExpression(const Variable * var)
diff --git a/lib/token.cpp b/lib/token.cpp
index 6e3b018f8..bce14ced5 100644
--- a/lib/token.cpp
+++ b/lib/token.cpp
@@ -1166,6 +1166,62 @@ void Token::astOperand2(Token *tok)
     mAstOperand2 = tok;
 }
 
+static const Token* goToLeftParenthesis(const Token* start, const Token* end)
+{
+    // move start to lpar in such expression: '(*it).x'
+    int par = 0;
+    for (const Token *tok = start; tok && tok != end; tok = tok->next()) {
+        if (tok->str() == "(")
+            ++par;
+        else if (tok->str() == ")") {
+            if (par == 0)
+                start = tok->link();
+            else
+                --par;
+        }
+    }
+    return start;
+}
+
+static const Token* goToRightParenthesis(const Token* start, const Token* end)
+{
+    // move end to rpar in such expression: '2>(x+1)'
+    int par = 0;
+    for (const Token *tok = end; tok && tok != start; tok = tok->previous()) {
+        if (tok->str() == ")")
+            ++par;
+        else if (tok->str() == "(") {
+            if (par == 0)
+                end = tok->link();
+            else
+                --par;
+        }
+    }
+    return end;
+}
+
+std::pair<const Token *, const Token *> Token::findExpressionStartEndTokens() const
+{
+    const Token * const top = this;
+    const Token *start = top;
+    while (start->astOperand1() &&
+           (start->astOperand2() || !start->isUnaryPreOp() || Token::simpleMatch(start, "( )") || start->str() == "{"))
+        start = start->astOperand1();
+    const Token *end = top;
+    while (end->astOperand1() && (end->astOperand2() || end->isUnaryPreOp())) {
+        if (Token::Match(end,"(|[") &&
+            !(Token::Match(end, "( %type%") && !end->astOperand2())) {
+            end = end->link();
+            break;
+        }
+        end = end->astOperand2() ? end->astOperand2() : end->astOperand1();
+    }
+
+    start = goToLeftParenthesis(start, end);
+    end = goToRightParenthesis(start, end);
+    return std::pair<const Token *, const Token *>(start,end);
+}
+
 bool Token::isCalculation() const
 {
     if (!Token::Match(this, "%cop%|++|--"))
@@ -1221,40 +1277,6 @@ bool Token::isUnaryPreOp() const
     return false; // <- guess
 }
 
-static const Token* goToLeftParenthesis(const Token* start, const Token* end)
-{
-    // move start to lpar in such expression: '(*it).x'
-    int par = 0;
-    for (const Token *tok = start; tok && tok != end; tok = tok->next()) {
-        if (tok->str() == "(")
-            ++par;
-        else if (tok->str() == ")") {
-            if (par == 0)
-                start = tok->link();
-            else
-                --par;
-        }
-    }
-    return start;
-}
-
-static const Token* goToRightParenthesis(const Token* start, const Token* end)
-{
-    // move end to rpar in such expression: '2>(x+1)'
-    int par = 0;
-    for (const Token *tok = end; tok && tok != start; tok = tok->previous()) {
-        if (tok->str() == ")")
-            ++par;
-        else if (tok->str() == "(") {
-            if (par == 0)
-                end = tok->link();
-            else
-                --par;
-        }
-    }
-    return end;
-}
-
 static std::string stringFromTokenRange(const Token* start, const Token* end)
 {
     std::ostringstream ret;
@@ -1277,25 +1299,8 @@ static std::string stringFromTokenRange(const Token* start, const Token* end)
 
 std::string Token::expressionString() const
 {
-    const Token * const top = this;
-    const Token *start = top;
-    while (start->astOperand1() &&
-           (start->astOperand2() || !start->isUnaryPreOp() || Token::simpleMatch(start, "( )") || start->str() == "{"))
-        start = start->astOperand1();
-    const Token *end = top;
-    while (end->astOperand1() && (end->astOperand2() || end->isUnaryPreOp())) {
-        if (Token::Match(end,"(|[") &&
-            !(Token::Match(end, "( %type%") && !end->astOperand2())) {
-            end = end->link();
-            break;
-        }
-        end = end->astOperand2() ? end->astOperand2() : end->astOperand1();
-    }
-
-    start = goToLeftParenthesis(start, end);
-    end = goToRightParenthesis(start, end);
-
-    return stringFromTokenRange(start, end);
+    const auto tokens = findExpressionStartEndTokens();
+    return stringFromTokenRange(tokens.first, tokens.second);
 }
 
 static void astStringXml(const Token *tok, std::size_t indent, std::ostream &out)
diff --git a/lib/token.h b/lib/token.h
index 9cf9d5886..094597c3e 100644
--- a/lib/token.h
+++ b/lib/token.h
@@ -1049,6 +1049,8 @@ public:
         return ret;
     }
 
+    std::pair<const Token *, const Token *> findExpressionStartEndTokens() const;
+
     /**
      * Is current token a calculation? Only true for operands.
      * For '*' and '&' tokens it is looked up if this is a