Bug 86654 - Cache final overrider maps in the AST

Change-Id: I33d79c160b7aa7b014042ea06e0b851abc9cb608
Signed-off-by: Nathan Ridge <zeratul976@hotmail.com>

2 files changed, 31 insertions, 3 deletions

diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/CPPASTTranslationUnit.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/CPPASTTranslationUnit.java
index 58f8062dae0..6ec93159519 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/CPPASTTranslationUnit.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/CPPASTTranslationUnit.java
@@ -12,6 +12,9 @@
  *******************************************************************************/
 package org.eclipse.cdt.internal.core.dom.parser.cpp;
 
+import java.util.HashMap;
+import java.util.Map;
+
 import org.eclipse.cdt.core.dom.ILinkage;
 import org.eclipse.cdt.core.dom.ast.IASTName;
 import org.eclipse.cdt.core.dom.ast.IASTNode;
@@ -33,6 +36,7 @@ import org.eclipse.cdt.core.parser.util.ArrayUtil;
 import org.eclipse.cdt.internal.core.dom.Linkage;
 import org.eclipse.cdt.internal.core.dom.parser.ASTTranslationUnit;
 import org.eclipse.cdt.internal.core.dom.parser.IASTAmbiguityParent;
+import org.eclipse.cdt.internal.core.dom.parser.cpp.semantics.CPPInheritance.FinalOverriderMap;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.semantics.CPPVisitor;
 import org.eclipse.cdt.internal.core.index.IIndexScope;
 import org.eclipse.cdt.internal.core.parser.scanner.InternalFileContent;
@@ -46,6 +50,9 @@ public class CPPASTTranslationUnit extends ASTTranslationUnit implements ICPPAST
 	private final CPPScopeMapper fScopeMapper= new CPPScopeMapper(this);
 	private CPPASTAmbiguityResolver fAmbiguityResolver;
 	
+	// Caches
+	private Map<ICPPClassType, FinalOverriderMap> fFinalOverriderMapCache = new HashMap<>();
+	
 	public CPPASTTranslationUnit() {
 	}
 	
@@ -211,4 +218,8 @@ public class CPPASTTranslationUnit extends ASTTranslationUnit implements ICPPAST
 			fAmbiguityResolver.resolvePendingAmbiguities(node);
 		}
 	}
+	
+	public Map<ICPPClassType, FinalOverriderMap> getFinalOverriderMapCache() {
+		return fFinalOverriderMapCache;
+	}
 }
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPInheritance.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPInheritance.java
index e09a06242e4..dce110964db 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPInheritance.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPInheritance.java
@@ -19,6 +19,7 @@ import org.eclipse.cdt.core.dom.ast.cpp.ICPPBase;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPClassType;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPMethod;
 import org.eclipse.cdt.core.parser.util.CollectionUtils;
+import org.eclipse.cdt.internal.core.dom.parser.cpp.CPPASTTranslationUnit;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.ClassTypeHelper;
 
 /**
@@ -96,13 +97,29 @@ public class CPPInheritance {
 
 	/**
 	 * Returns the final overrider map for a class hierarchy.
-	 *
+	 * Final overrider maps are cached in the AST.
+	 * 
 	 * @param classType the root of the class hierarchy
-	 * @param point the point of template instantiation, if applicable
+	 * @param point The point of template instantiation, if applicable.
+	 *              Also used to access the cache in the AST.
 	 * @return the computed final overrider map
 	 */
 	public static FinalOverriderMap getFinalOverriderMap(ICPPClassType classType, IASTNode point) {
-		return FinalOverriderAnalysis.computeFinalOverriderMap(classType, point);
+		Map<ICPPClassType, FinalOverriderMap> cache = null;
+		if (point != null && point.getTranslationUnit() instanceof CPPASTTranslationUnit) {
+			cache = ((CPPASTTranslationUnit) point.getTranslationUnit()).getFinalOverriderMapCache();
+		}
+		FinalOverriderMap result = null;
+		if (cache != null) {
+			result = cache.get(classType);
+		}
+		if (result == null) {
+			result = FinalOverriderAnalysis.computeFinalOverriderMap(classType, point);
+		}
+		if (result != null && cache != null) {
+			cache.put(classType, result);
+		}
+		return result;
 	}
 
 	private static class FinalOverriderAnalysis {