Augment the interface of ExternalASTSource::FindExternalLexicalDecls()

to allow clients to specify that they've already (correctly) loaded
declarations, and that no further action is needed.

Also, make sure that we clear the "has external lexical declarations"
bit before calling FindExternalLexicalDecls(), to avoid infinite
recursion.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@135306 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/AST/ExternalASTSource.h b/include/clang/AST/ExternalASTSource.h
index 846813adf7c34e137eaa59b65b7324aa81220d0a..ef1f1618ba1d8ababf37626bb5398255ca50afeb 100644 (file)
--- a/include/clang/AST/ExternalASTSource.h
+++ b/include/clang/AST/ExternalASTSource.h
@@ -32,6 +32,20 @@ class Selector;
 class Stmt;
 class TagDecl;
 
+/// \brief Enumeration describing the result of loading information from
+/// an external source.
+enum ExternalLoadResult {
+  /// \brief Loading the external information has succeeded.
+  ELR_Success,
+  
+  /// \brief Loading the external information has failed.
+  ELR_Failure,
+  
+  /// \brief The external information has already been loaded, and therefore
+  /// no additional processing is required.
+  ELR_AlreadyLoaded
+};
+  
 /// \brief Abstract interface for external sources of AST nodes.
 ///
 /// External AST sources provide AST nodes constructed from some
@@ -132,10 +146,10 @@ public:
   /// declaration kind is one we are looking for. If NULL, all declarations
   /// are returned.
   ///
-  /// \return true if an error occurred
+  /// \return an indication of whether the load succeeded or failed.
   ///
   /// The default implementation of this method is a no-op.
-  virtual bool FindExternalLexicalDecls(const DeclContext *DC,
+  virtual ExternalLoadResult FindExternalLexicalDecls(const DeclContext *DC,
                                         bool (*isKindWeWant)(Decl::Kind),
                                         llvm::SmallVectorImpl<Decl*> &Result);
 
@@ -143,14 +157,14 @@ public:
   /// DeclContext.
   ///
   /// \return true if an error occurred
-  bool FindExternalLexicalDecls(const DeclContext *DC,
+  ExternalLoadResult FindExternalLexicalDecls(const DeclContext *DC,
                                 llvm::SmallVectorImpl<Decl*> &Result) {
     return FindExternalLexicalDecls(DC, 0, Result);
   }
 
   template <typename DeclTy>
-  bool FindExternalLexicalDeclsBy(const DeclContext *DC,
-                                llvm::SmallVectorImpl<Decl*> &Result) {
+  ExternalLoadResult FindExternalLexicalDeclsBy(const DeclContext *DC,
+                                  llvm::SmallVectorImpl<Decl*> &Result) {
     return FindExternalLexicalDecls(DC, DeclTy::classofKind, Result);
   }
 

diff --git a/include/clang/Serialization/ASTReader.h b/include/clang/Serialization/ASTReader.h
index a6c32aafd3356cf1b344eb32b0046db90f10fac6..9e210c3db28cb152ddacec801c080e92539f2c40 100644 (file)
--- a/include/clang/Serialization/ASTReader.h
+++ b/include/clang/Serialization/ASTReader.h
@@ -1070,7 +1070,7 @@ public:
   ///
   /// \returns true if there was an error while reading the
   /// declarations for this declaration context.
-  virtual bool FindExternalLexicalDecls(const DeclContext *DC,
+  virtual ExternalLoadResult FindExternalLexicalDecls(const DeclContext *DC,
                                         bool (*isKindWeWant)(Decl::Kind),
                                         llvm::SmallVectorImpl<Decl*> &Decls);
 

diff --git a/include/clang/Serialization/ChainedIncludesSource.h b/include/clang/Serialization/ChainedIncludesSource.h
index 0c3e86faf414f50614a129260e71c0402ead4346..f547902ef0eb1d94a54e121ba9cccc499e29a447 100644 (file)
--- a/include/clang/Serialization/ChainedIncludesSource.h
+++ b/include/clang/Serialization/ChainedIncludesSource.h
@@ -47,7 +47,7 @@ protected:
   virtual DeclContextLookupResult
   FindExternalVisibleDeclsByName(const DeclContext *DC, DeclarationName Name);
   virtual void MaterializeVisibleDecls(const DeclContext *DC);
-  virtual bool FindExternalLexicalDecls(const DeclContext *DC,
+  virtual ExternalLoadResult FindExternalLexicalDecls(const DeclContext *DC,
                                         bool (*isKindWeWant)(Decl::Kind),
                                         llvm::SmallVectorImpl<Decl*> &Result);
   virtual void CompleteType(TagDecl *Tag);

diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 9b507cfc5e2425a6e1c9f1b96167b9f94ddd6536..4c323da7eee3fb6525ced64689faae75fc66f037 100644 (file)
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -2361,8 +2361,15 @@ void RecordDecl::LoadFieldsFromExternalStorage() const {
   ExternalASTSource::Deserializing TheFields(Source);
 
   llvm::SmallVector<Decl*, 64> Decls;
-  if (Source->FindExternalLexicalDeclsBy<FieldDecl>(this, Decls))
+  LoadedFieldsFromExternalStorage = true;  
+  switch (Source->FindExternalLexicalDeclsBy<FieldDecl>(this, Decls)) {
+  case ELR_Success:
+    break;
+    
+  case ELR_AlreadyLoaded:
+  case ELR_Failure:
     return;
+  }
 
 #ifndef NDEBUG
   // Check that all decls we got were FieldDecls.
@@ -2370,8 +2377,6 @@ void RecordDecl::LoadFieldsFromExternalStorage() const {
     assert(isa<FieldDecl>(Decls[i]));
 #endif
 
-  LoadedFieldsFromExternalStorage = true;
-
   if (Decls.empty())
     return;
 

diff --git a/lib/AST/DeclBase.cpp b/lib/AST/DeclBase.cpp
index 7d146572bf6d2cac525a754c11875685c9cc0c8c..b2806f092cbdcaecb354e1cf05cb895282410f56 100644 (file)
--- a/lib/AST/DeclBase.cpp
+++ b/lib/AST/DeclBase.cpp
@@ -839,12 +839,17 @@ DeclContext::LoadLexicalDeclsFromExternalStorage() const {
   // Notify that we have a DeclContext that is initializing.
   ExternalASTSource::Deserializing ADeclContext(Source);
 
+  // Load the external declarations, if any.
   llvm::SmallVector<Decl*, 64> Decls;
-  if (Source->FindExternalLexicalDecls(this, Decls))
-    return;
-
-  // There is no longer any lexical storage in this context
   ExternalLexicalStorage = false;
+  switch (Source->FindExternalLexicalDecls(this, Decls)) {
+  case ELR_Success:
+    break;
+    
+  case ELR_Failure:
+  case ELR_AlreadyLoaded:
+    return;
+  }
 
   if (Decls.empty())
     return;

diff --git a/lib/AST/ExternalASTSource.cpp b/lib/AST/ExternalASTSource.cpp
index f428318a21e329795ca5c79aa0bbfc819ab7b06f..b96d65a729cae29eff1a6bb392d632fd74ccf764 100644 (file)
--- a/lib/AST/ExternalASTSource.cpp
+++ b/lib/AST/ExternalASTSource.cpp
@@ -51,11 +51,11 @@ ExternalASTSource::FindExternalVisibleDeclsByName(const DeclContext *DC,
 
 void ExternalASTSource::MaterializeVisibleDecls(const DeclContext *DC) { }
 
-bool 
+ExternalLoadResult 
 ExternalASTSource::FindExternalLexicalDecls(const DeclContext *DC,
                                             bool (*isKindWeWant)(Decl::Kind),
                                          llvm::SmallVectorImpl<Decl*> &Result) {
-  return true;
+  return ELR_AlreadyLoaded;
 }
 
 void ExternalASTSource::getMemoryBufferSizes(MemoryBufferSizes &sizes) const { }

diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index 13933b3eb3f2da5d73351dd12f8d232e29e5cf7c..a4ed5f4da48c1a6781e14d9213ea82034ae78b25 100644 (file)
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -4008,12 +4008,9 @@ Stmt *ASTReader::GetExternalDeclStmt(uint64_t Offset) {
   llvm_unreachable("Broken chain");
 }
 
-bool ASTReader::FindExternalLexicalDecls(const DeclContext *DC,
+ExternalLoadResult ASTReader::FindExternalLexicalDecls(const DeclContext *DC,
                                          bool (*isKindWeWant)(Decl::Kind),
                                          llvm::SmallVectorImpl<Decl*> &Decls) {
-  assert(DC->hasExternalLexicalStorage() &&
-         "DeclContext has no lexical decls in storage");
-
   // There might be lexical decls in multiple parts of the chain, for the TU
   // at least.
   // DeclContextOffsets might reallocate as we load additional decls below,
@@ -4038,7 +4035,7 @@ bool ASTReader::FindExternalLexicalDecls(const DeclContext *DC,
   }
 
   ++NumLexicalDeclContextsRead;
-  return false;
+  return ELR_Success;
 }
 
 DeclContext::lookup_result

diff --git a/lib/Serialization/ChainedIncludesSource.cpp b/lib/Serialization/ChainedIncludesSource.cpp
index da5be957a530f993a10cf6628cfa38915fa520ae..3b7cd23b92ae411339ea790e276cb49afd764027 100644 (file)
--- a/lib/Serialization/ChainedIncludesSource.cpp
+++ b/lib/Serialization/ChainedIncludesSource.cpp
@@ -185,7 +185,8 @@ ChainedIncludesSource::FindExternalVisibleDeclsByName(const DeclContext *DC,
 void ChainedIncludesSource::MaterializeVisibleDecls(const DeclContext *DC) {
   return getFinalReader().MaterializeVisibleDecls(DC);
 }
-bool ChainedIncludesSource::FindExternalLexicalDecls(const DeclContext *DC,
+ExternalLoadResult 
+ChainedIncludesSource::FindExternalLexicalDecls(const DeclContext *DC,
                                       bool (*isKindWeWant)(Decl::Kind),
                                       llvm::SmallVectorImpl<Decl*> &Result) {
   return getFinalReader().FindExternalLexicalDecls(DC, isKindWeWant, Result);