Token: introduced cache for isAliasOf() calls

Author: firewave

lib/astutils.cpp

@@ -2920,7 +2920,7 @@ static bool isExpressionChangedAt(const F& getExprTok,
         if (!expr && !(tok->valueType() && tok->valueType()->pointer == 0 && tok->valueType()->reference == Reference::None))
             aliased = true;
         if (!aliased)
-            aliased = isAliasOf(tok, expr, &i);
+            aliased = tok->isAliasOf(expr, &i);
         if (!aliased)
             return false;
         if (isVariableChanged(tok, indirect + i, settings, depth))

lib/token.cpp

@@ -2754,3 +2754,20 @@ const SmallVector<ReferenceToken>& Token::refs(bool temporary) const
         mImpl->mRefs = new SmallVector<ReferenceToken>(followAllReferences(this, false));
     return *mImpl->mRefs;
 }
+
+bool Token::isAliasOf(const Token* expr, int* indirect) const
+{
+    auto it = mImpl->mAliases.find(expr);
+    if (it != mImpl->mAliases.end()) {
+        if (indirect)
+            *indirect = it->second.second;
+        return it->second.first;
+    }
+    int i = 0;
+    const bool b = ::isAliasOf(this, expr, &i);
+    mImpl->mAliases[expr] = std::make_pair(b, i);
+    if (indirect)
+        *indirect = i;
+    return b;
+}
+

lib/token.h

@@ -154,6 +154,8 @@ struct TokenImpl {
     SmallVector<ReferenceToken>* mRefs{};
     SmallVector<ReferenceToken>* mRefsTemp{};
 
+    std::map<const Token*, std::pair<bool, int>> mAliases;
+
     TokenImpl() : mFunction(nullptr) {}
 
     ~TokenImpl();
@@ -1357,6 +1359,8 @@ class CPPCHECKLIB Token {
     // provides and caches result of a followAllReferences() call
     const SmallVector<ReferenceToken>& refs(bool temporary = true) const;
 
+    bool isAliasOf(const Token* expr, int* indirect) const;
+
     /**
      * Sets the original name.
      */