cmGeneratorExpressionDAGChecker: Simplify finding evaluation graph root

Source/cmGeneratorExpressionDAGChecker.cxx

@@ -31,12 +31,13 @@ cmGeneratorExpressionDAGChecker::cmGeneratorExpressionDAGChecker(
   std::string property, const GeneratorExpressionContent* content,
   cmGeneratorExpressionDAGChecker* parent)
   : Parent(parent)
+  , Top(parent ? parent->Top : this)
   , Target(target)
   , Property(std::move(property))
   , Content(content)
   , Backtrace(std::move(backtrace))
 {
-  const auto* top = this->Top();
+  const auto* top = this->Top;
   this->CheckResult = this->CheckGraph();
 
 #define TEST_TRANSITIVE_PROPERTY_METHOD(METHOD) top->METHOD() ||
@@ -129,13 +130,13 @@ cmGeneratorExpressionDAGChecker::CheckGraph() const
 
 bool cmGeneratorExpressionDAGChecker::GetTransitivePropertiesOnly() const
 {
-  return this->Top()->TransitivePropertiesOnly;
+  return this->Top->TransitivePropertiesOnly;
 }
 
 bool cmGeneratorExpressionDAGChecker::GetTransitivePropertiesOnlyCMP0131()
   const
 {
-  return this->Top()->CMP0131;
+  return this->Top->CMP0131;
 }
 
 bool cmGeneratorExpressionDAGChecker::EvaluatingGenexExpression() const
@@ -146,12 +147,12 @@ bool cmGeneratorExpressionDAGChecker::EvaluatingGenexExpression() const
 
 bool cmGeneratorExpressionDAGChecker::EvaluatingPICExpression() const
 {
-  return this->Top()->Property == "INTERFACE_POSITION_INDEPENDENT_CODE";
+  return this->Top->Property == "INTERFACE_POSITION_INDEPENDENT_CODE";
 }
 
 bool cmGeneratorExpressionDAGChecker::EvaluatingCompileExpression() const
 {
-  cm::string_view property(this->Top()->Property);
+  cm::string_view property(this->Top->Property);
 
   return property == "INCLUDE_DIRECTORIES"_s ||
     property == "COMPILE_DEFINITIONS"_s || property == "COMPILE_OPTIONS"_s;
@@ -159,7 +160,7 @@ bool cmGeneratorExpressionDAGChecker::EvaluatingCompileExpression() const
 
 bool cmGeneratorExpressionDAGChecker::EvaluatingLinkExpression() const
 {
-  cm::string_view property(this->Top()->Property);
+  cm::string_view property(this->Top->Property);
 
   return property == "LINK_DIRECTORIES"_s || property == "LINK_OPTIONS"_s ||
     property == "LINK_DEPENDS"_s || property == "LINK_LIBRARY_OVERRIDE"_s ||
@@ -168,14 +169,14 @@ bool cmGeneratorExpressionDAGChecker::EvaluatingLinkExpression() const
 
 bool cmGeneratorExpressionDAGChecker::EvaluatingLinkOptionsExpression() const
 {
-  cm::string_view property(this->Top()->Property);
+  cm::string_view property(this->Top->Property);
 
   return property == "LINK_OPTIONS"_s || property == "LINKER_TYPE"_s;
 }
 
 bool cmGeneratorExpressionDAGChecker::EvaluatingLinkerLauncher() const
 {
-  cm::string_view property(this->Top()->Property);
+  cm::string_view property(this->Top->Property);
 
   return property.length() > cmStrLen("_LINKER_LAUNCHER") &&
     property.substr(property.length() - cmStrLen("_LINKER_LAUNCHER")) ==
@@ -185,7 +186,7 @@ bool cmGeneratorExpressionDAGChecker::EvaluatingLinkerLauncher() const
 bool cmGeneratorExpressionDAGChecker::EvaluatingLinkLibraries(
   cmGeneratorTarget const* tgt, ForGenex genex) const
 {
-  const auto* top = this->Top();
+  const auto* top = this->Top;
 
   cm::string_view prop(top->Property);
 
@@ -206,21 +207,9 @@ bool cmGeneratorExpressionDAGChecker::EvaluatingLinkLibraries(
     : (result || prop == "INTERFACE_LINK_LIBRARIES_DIRECT_EXCLUDE"_s);
 }
 
-cmGeneratorExpressionDAGChecker const* cmGeneratorExpressionDAGChecker::Top()
-  const
-{
-  const cmGeneratorExpressionDAGChecker* top = this;
-  const cmGeneratorExpressionDAGChecker* parent = this->Parent;
-  while (parent) {
-    top = parent;
-    parent = parent->Parent;
-  }
-  return top;
-}
-
 cmGeneratorTarget const* cmGeneratorExpressionDAGChecker::TopTarget() const
 {
-  return this->Top()->Target;
+  return this->Top->Target;
 }
 
 enum class TransitiveProperty

Source/cmGeneratorExpressionDAGChecker.h

@@ -94,13 +94,13 @@ struct cmGeneratorExpressionDAGChecker
   bool GetTransitivePropertiesOnlyCMP0131() const;
   void SetTransitivePropertiesOnlyCMP0131() { this->CMP0131 = true; }
 
-  cmGeneratorExpressionDAGChecker const* Top() const;
   cmGeneratorTarget const* TopTarget() const;
 
 private:
   Result CheckGraph() const;
 
   const cmGeneratorExpressionDAGChecker* const Parent;
+  const cmGeneratorExpressionDAGChecker* const Top;
   cmGeneratorTarget const* Target;
   const std::string Property;
   mutable std::map<cmGeneratorTarget const*, std::set<std::string>> Seen;