Fast copy between TypedData and ExternalTypedData

runtime/lib/typeddata.cc

Index: runtime/lib/typeddata.cc
diff --git a/runtime/lib/typeddata.cc b/runtime/lib/typeddata.cc
index d9859751826042829d86f41cc4353fe26c166478..7b1e118dc76236ebc0787b6bcd3ad46f1c6671e1 100644
--- a/runtime/lib/typeddata.cc
+++ b/runtime/lib/typeddata.cc
@@ -79,24 +79,34 @@ DEFINE_NATIVE_ENTRY(TypedData_length, 1) {
 }
 
 
-#define COPY_DATA(type, dst, src)                                              \
-  const type& dst_array = type::Cast(dst);                                     \
-  const type& src_array = type::Cast(src);                                     \
-  intptr_t element_size_in_bytes = dst_array.ElementSizeInBytes();             \
-  intptr_t length_in_bytes = length.Value() * element_size_in_bytes;           \
-  intptr_t src_offset_in_bytes = src_start.Value() * element_size_in_bytes;    \
-  intptr_t dst_offset_in_bytes = dst_start.Value() * element_size_in_bytes;    \
+#define COPY_DATA_AND_RETURN(dsttype, dst, srctype, src)                       \

[Vyacheslav Egorov (Google), 2013/04/16 14:22:23]

I'd prefer good old template to this huge macro.

+  const dsttype& dst_array = dsttype::Cast(dst);                               \
+  const srctype& src_array = srctype::Cast(src);                               \
+  intptr_t dst_element_size_in_bytes = dst_array.ElementSizeInBytes();         \
+  intptr_t src_element_size_in_bytes = src_array.ElementSizeInBytes();         \
+  intptr_t dst_offset_in_bytes = dst_start.Value() * dst_element_size_in_bytes;\
+  intptr_t src_offset_in_bytes = src_start.Value() * src_element_size_in_bytes;\
+  intptr_t length_in_bytes = length.Value() * src_element_size_in_bytes;       \
+  if (src_element_size_in_bytes != dst_element_size_in_bytes) {                \
+    return Bool::False().raw();                                                \
+  }                                                                            \
   SetRangeCheck(src_offset_in_bytes,                                           \
                 length_in_bytes,                                               \
                 src_array.LengthInBytes(),                                     \
-                element_size_in_bytes);                                        \
+                src_element_size_in_bytes);                                    \
   SetRangeCheck(dst_offset_in_bytes,                                           \
                 length_in_bytes,                                               \
                 dst_array.LengthInBytes(),                                     \
-                element_size_in_bytes);                                        \
-  type::Copy(dst_array, dst_offset_in_bytes,                                   \
-             src_array, src_offset_in_bytes,                                   \
-             length_in_bytes);
+                dst_element_size_in_bytes);                                    \
+  {                                                                            \
+    NoGCScope no_gc;                                                           \
+    if (length_in_bytes > 0) {                                                 \
+      memmove(dst_array.DataAddr(dst_offset_in_bytes),                         \
+              src_array.DataAddr(src_offset_in_bytes),                         \
+              length_in_bytes);                                                \
+    }                                                                          \
+    return Bool::True().raw();                                                 \
+  }
 
 DEFINE_NATIVE_ENTRY(TypedData_setRange, 5) {
   GET_NON_NULL_NATIVE_ARGUMENT(Instance, dst, arguments->NativeArgAt(0));
@@ -112,17 +122,18 @@ DEFINE_NATIVE_ENTRY(TypedData_setRange, 5) {
     args.SetAt(0, error);
     Exceptions::ThrowByType(Exceptions::kArgument, args);
   }
-  if ((dst.IsTypedData() || dst.IsExternalTypedData()) &&
-      (dst.clazz() == src.clazz())) {
-    if (dst.IsTypedData()) {
-      ASSERT(src.IsTypedData());
-      COPY_DATA(TypedData, dst, src);
-    } else {
-      ASSERT(src.IsExternalTypedData());
-      ASSERT(dst.IsExternalTypedData());
-      COPY_DATA(ExternalTypedData, dst, src);
+  if (dst.IsTypedData()) {
+    if (src.IsTypedData()) {
+      COPY_DATA_AND_RETURN(TypedData, dst, TypedData, src);
+    } else if (src.IsExternalTypedData()) {
+      COPY_DATA_AND_RETURN(TypedData, dst, ExternalTypedData, src);
+    }
+  } else if (dst.IsExternalTypedData()) {
+    if (src.IsTypedData()) {
+      COPY_DATA_AND_RETURN(ExternalTypedData, dst, TypedData, src);
+    } else if (src.IsExternalTypedData()) {
+      COPY_DATA_AND_RETURN(ExternalTypedData, dst, ExternalTypedData, src);
     }
-    return Bool::True().raw();
   }
   return Bool::False().raw();
 }