Refactor the code that walks a C++ inheritance hierarchy, searching

for bases, members, overridden virtual methods, etc. The operations
isDerivedFrom and lookupInBases are now provided by CXXRecordDecl,
rather than by Sema, so that CodeGen and other clients can use them
directly.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@83396 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 37 insertions, 6 deletions

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 8e69caae5c..a1fcf89c54 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -12,11 +12,11 @@
 //===----------------------------------------------------------------------===//
 
 #include "Sema.h"
-#include "SemaInherit.h"
 #include "clang/AST/APValue.h"
 #include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/Analysis/CFG.h"
+#include "clang/AST/CXXInheritance.h"
 #include "clang/AST/DeclObjC.h"
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/ExprCXX.h"
@@ -2455,6 +2455,35 @@ static bool isUsingDecl(Decl *D) {
   return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D);
 }
 
+/// \brief Data used with FindOverriddenMethod
+struct FindOverriddenMethodData {
+  Sema *S;
+  CXXMethodDecl *Method;
+};
+
+/// \brief Member lookup function that determines whether a given C++
+/// method overrides a method in a base class, to be used with
+/// CXXRecordDecl::lookupInBases().
+static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier,
+                                 CXXBasePath &Path,
+                                 void *UserData) {
+  RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl();
+  
+  FindOverriddenMethodData *Data 
+    = reinterpret_cast<FindOverriddenMethodData*>(UserData);
+  for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName());
+       Path.Decls.first != Path.Decls.second;
+       ++Path.Decls.first) {
+    if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) {
+      OverloadedFunctionDecl::function_iterator MatchedDecl;
+      if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl))
+        return true;
+    }
+  }
+  
+  return false;
+}
+
 NamedDecl*
 Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC,
                               QualType R, DeclaratorInfo *DInfo,
@@ -2690,11 +2719,13 @@ Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC,
 
   if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) {
     // Look for virtual methods in base classes that this method might override.
-
-    BasePaths Paths;
-    if (LookupInBases(cast<CXXRecordDecl>(DC),
-                      MemberLookupCriteria(NewMD), Paths)) {
-      for (BasePaths::decl_iterator I = Paths.found_decls_begin(),
+    CXXBasePaths Paths;
+    FindOverriddenMethodData Data;
+    Data.Method = NewMD;
+    Data.S = this;
+    if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data,
+                                                Paths)) {
+      for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(),
            E = Paths.found_decls_end(); I != E; ++I) {
         if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) {
           if (!CheckOverridingFunctionReturnType(NewMD, OldMD) &&