Implement basic __is_trivial type-trait support, enough to close PR9472.

This introduces a few APIs on the AST to bundle up the standard-based
logic so that programmatic clients have access to exactly the same
behavior.

There is only one serious FIXME here: checking for non-trivial move
constructors and move assignment operators. Those bits need to be added
to the declaration and accessors provided.

This implementation should be enough for the uses of __is_trivial in
libstdc++ 4.6's C++98 library implementation.

Ideas for more thorough test cases or any edge cases missing would be
appreciated. =D

llvm-svn: 130057

4 files changed, 10 insertions, 0 deletions

diff --git a/clang/include/clang/AST/DeclCXX.h b/clang/include/clang/AST/DeclCXX.h
index 76510ca3148..dfd3bd6e262 100644
--- a/clang/include/clang/AST/DeclCXX.h
+++ b/clang/include/clang/AST/DeclCXX.h
@@ -741,6 +741,10 @@ public:
   // (C++ [class.dtor]p3)
   bool hasTrivialDestructor() const { return data().HasTrivialDestructor; }
 
+  // isTriviallyCopyable - Whether this class is considered trivially copyable
+  // (C++0x [class]p5).
+  bool isTriviallyCopyable() const;
+
   /// \brief If this record is an instantiation of a member class,
   /// retrieves the member class from which it was instantiated.
   ///
diff --git a/clang/include/clang/AST/Type.h b/clang/include/clang/AST/Type.h
index 5d1588726b9..9ed30563598 100644
--- a/clang/include/clang/AST/Type.h
+++ b/clang/include/clang/AST/Type.h
@@ -1171,6 +1171,10 @@ public:
   /// (C++0x [basic.types]p10)
   bool isLiteralType() const;
 
+  /// isTrivialType - Return true if this is a literal type
+  /// (C++0x [basic.types]p9)
+  bool isTrivialType() const;
+
   /// Helper methods to distinguish type categories. All type predicates
   /// operate on the canonical type, ignoring typedefs and qualifiers.
 
diff --git a/clang/include/clang/Basic/TokenKinds.def b/clang/include/clang/Basic/TokenKinds.def
index 6e0dd056a1a..96f5aa9cada 100644
--- a/clang/include/clang/Basic/TokenKinds.def
+++ b/clang/include/clang/Basic/TokenKinds.def
@@ -340,6 +340,7 @@ KEYWORD(__is_enum                   , KEYCXX)
 KEYWORD(__is_literal                , KEYCXX)
 KEYWORD(__is_pod                    , KEYCXX)
 KEYWORD(__is_polymorphic            , KEYCXX)
+KEYWORD(__is_trivial                , KEYCXX)
 KEYWORD(__is_union                  , KEYCXX)
 
 // Apple Extension.
diff --git a/clang/include/clang/Basic/TypeTraits.h b/clang/include/clang/Basic/TypeTraits.h
index 791ed34bc3f..5883efe3bb0 100644
--- a/clang/include/clang/Basic/TypeTraits.h
+++ b/clang/include/clang/Basic/TypeTraits.h
@@ -33,6 +33,7 @@ namespace clang {
     UTT_IsLiteral,
     UTT_IsPOD,
     UTT_IsPolymorphic,
+    UTT_IsTrivial,
     UTT_IsUnion
   };