Add traits to common utils data structures.

Many of our basic data structures are trivially movable using
memcpy() even if they are not trivially constructable, destructable
or copyable.  It's worth taking advantage of this *ahem* trait.

Adding trivial_move_trait to String16 reduces appt running
time on frameworks/base/core/res by 40%!

Change-Id: I630a1a027e2d0ded96856e4ca042ea82906289fe

include/utils/BitSet.h

@@ -18,6 +18,7 @@
 #define UTILS_BITSET_H
 
 #include <stdint.h>
+#include <utils/TypeHelpers.h>
 
 /*
  * Contains some bit manipulation helpers.
@@ -102,6 +103,8 @@ struct BitSet32 {
     inline bool operator!= (const BitSet32& other) const { return value != other.value; }
 };
 
+ANDROID_BASIC_TYPES_TRAITS(BitSet32)
+
 } // namespace android
 
 #endif // UTILS_BITSET_H

include/utils/KeyedVector.h

@@ -91,6 +91,13 @@ private:
             SortedVector< key_value_pair_t<KEY, VALUE> >    mVector;
 };
 
+// KeyedVector<KEY, VALUE> can be trivially moved using memcpy() because its
+// underlying SortedVector can be trivially moved.
+template<typename KEY, typename VALUE> struct trait_trivial_move<KeyedVector<KEY, VALUE> > {
+    enum { value = trait_trivial_move<SortedVector< key_value_pair_t<KEY, VALUE> > >::value };
+};
+
+
 // ---------------------------------------------------------------------------
 
 /**

include/utils/RefBase.h

@@ -25,6 +25,7 @@
 #include <string.h>
 
 #include <utils/StrongPointer.h>
+#include <utils/TypeHelpers.h>
 
 // ---------------------------------------------------------------------------
 namespace android {

include/utils/SortedVector.h

@@ -133,6 +133,9 @@ protected:
     virtual int     do_compare(const void* lhs, const void* rhs) const;
 };
 
+// SortedVector<T> can be trivially moved using memcpy() because moving does not
+// require any change to the underlying SharedBuffer contents or reference count.
+template<typename T> struct trait_trivial_move<SortedVector<T> > { enum { value = true }; };
 
 // ---------------------------------------------------------------------------
 // No user serviceable parts from here...

include/utils/String16.h

@@ -20,6 +20,7 @@
 #include <utils/Errors.h>
 #include <utils/SharedBuffer.h>
 #include <utils/Unicode.h>
+#include <utils/TypeHelpers.h>
 
 // ---------------------------------------------------------------------------
 
@@ -112,6 +113,10 @@ private:
             const char16_t*     mString;
 };
 
+// String16 can be trivially moved using memcpy() because moving does not
+// require any change to the underlying SharedBuffer contents or reference count.
+ANDROID_TRIVIAL_MOVE_TRAIT(String16)
+
 TextOutput& operator<<(TextOutput& to, const String16& val);
 
 // ---------------------------------------------------------------------------

include/utils/String8.h

@@ -20,6 +20,7 @@
 #include <utils/Errors.h>
 #include <utils/SharedBuffer.h>
 #include <utils/Unicode.h>
+#include <utils/TypeHelpers.h>
 
 #include <string.h> // for strcmp
 #include <stdarg.h>
@@ -219,6 +220,10 @@ private:
             const char* mString;
 };
 
+// String8 can be trivially moved using memcpy() because moving does not
+// require any change to the underlying SharedBuffer contents or reference count.
+ANDROID_TRIVIAL_MOVE_TRAIT(String8)
+
 TextOutput& operator<<(TextOutput& to, const String16& val);
 
 // ---------------------------------------------------------------------------

include/utils/TypeHelpers.h

@@ -68,12 +68,24 @@ struct aggregate_traits {
     };
 };
 
-#define ANDROID_BASIC_TYPES_TRAITS( T )                                     \
-    template<> struct trait_trivial_ctor< T >   { enum { value = true }; }; \
-    template<> struct trait_trivial_dtor< T >   { enum { value = true }; }; \
-    template<> struct trait_trivial_copy< T >   { enum { value = true }; }; \
+#define ANDROID_TRIVIAL_CTOR_TRAIT( T ) \
+    template<> struct trait_trivial_ctor< T >   { enum { value = true }; };
+
+#define ANDROID_TRIVIAL_DTOR_TRAIT( T ) \
+    template<> struct trait_trivial_dtor< T >   { enum { value = true }; };
+
+#define ANDROID_TRIVIAL_COPY_TRAIT( T ) \
+    template<> struct trait_trivial_copy< T >   { enum { value = true }; };
+
+#define ANDROID_TRIVIAL_MOVE_TRAIT( T ) \
     template<> struct trait_trivial_move< T >   { enum { value = true }; };
 
+#define ANDROID_BASIC_TYPES_TRAITS( T ) \
+    ANDROID_TRIVIAL_CTOR_TRAIT( T ) \
+    ANDROID_TRIVIAL_DTOR_TRAIT( T ) \
+    ANDROID_TRIVIAL_COPY_TRAIT( T ) \
+    ANDROID_TRIVIAL_MOVE_TRAIT( T )
+
 // ---------------------------------------------------------------------------
 
 /*

include/utils/Vector.h

@@ -201,6 +201,9 @@ protected:
     virtual void    do_move_backward(void* dest, const void* from, size_t num) const;
 };
 
+// Vector<T> can be trivially moved using memcpy() because moving does not
+// require any change to the underlying SharedBuffer contents or reference count.
+template<typename T> struct trait_trivial_move<Vector<T> > { enum { value = true }; };
 
 // ---------------------------------------------------------------------------
 // No user serviceable parts from here...