Reduce unnecessary COW on Vector by make writing explicit

This commit makes operator[] on Vector const and adds a write proxy to it.  From
now on writes to Vectors need to happen through the .write proxy. So for
instance:

Vector<int> vec;
vec.push_back(10);
std::cout << vec[0] << std::endl;
vec.write[0] = 20;

Failing to use the .write proxy will cause a compilation error.

In addition COWable datatypes can now embed a CowData pointer to their data.
This means that String, CharString, and VMap no longer use or derive from
Vector.

_ALWAYS_INLINE_ and _FORCE_INLINE_ are now equivalent for debug and non-debug
builds. This is a lot faster for Vector in the editor and while running tests.
The reason why this difference used to exist is because force-inlined methods
used to give a bad debugging experience. After extensive testing with modern
compilers this is no longer the case.

1 files changed, 9 insertions, 9 deletions

diff --git a/core/packed_data_container.cpp b/core/packed_data_container.cpp
index eaccdba9bf..45e060fa4a 100644
--- a/core/packed_data_container.cpp
+++ b/core/packed_data_container.cpp
@@ -251,7 +251,7 @@ uint32_t PackedDataContainer::_pack(const Variant &p_data, Vector<uint8_t> &tmpd
 			int len;
 			encode_variant(p_data, NULL, len);
 			tmpdata.resize(tmpdata.size() + len);
-			encode_variant(p_data, &tmpdata[pos], len);
+			encode_variant(p_data, &tmpdata.write[pos], len);
 			return pos;
 
 		} break;
@@ -268,8 +268,8 @@ uint32_t PackedDataContainer::_pack(const Variant &p_data, Vector<uint8_t> &tmpd
 			uint32_t pos = tmpdata.size();
 			int len = d.size();
 			tmpdata.resize(tmpdata.size() + len * 12 + 8);
-			encode_uint32(TYPE_DICT, &tmpdata[pos + 0]);
-			encode_uint32(len, &tmpdata[pos + 4]);
+			encode_uint32(TYPE_DICT, &tmpdata.write[pos + 0]);
+			encode_uint32(len, &tmpdata.write[pos + 4]);
 
 			List<Variant> keys;
 			d.get_key_list(&keys);
@@ -288,11 +288,11 @@ uint32_t PackedDataContainer::_pack(const Variant &p_data, Vector<uint8_t> &tmpd
 			int idx = 0;
 			for (List<DictKey>::Element *E = sortk.front(); E; E = E->next()) {
 
-				encode_uint32(E->get().hash, &tmpdata[pos + 8 + idx * 12 + 0]);
+				encode_uint32(E->get().hash, &tmpdata.write[pos + 8 + idx * 12 + 0]);
 				uint32_t ofs = _pack(E->get().key, tmpdata, string_cache);
-				encode_uint32(ofs, &tmpdata[pos + 8 + idx * 12 + 4]);
+				encode_uint32(ofs, &tmpdata.write[pos + 8 + idx * 12 + 4]);
 				ofs = _pack(d[E->get().key], tmpdata, string_cache);
-				encode_uint32(ofs, &tmpdata[pos + 8 + idx * 12 + 8]);
+				encode_uint32(ofs, &tmpdata.write[pos + 8 + idx * 12 + 8]);
 				idx++;
 			}
 
@@ -306,13 +306,13 @@ uint32_t PackedDataContainer::_pack(const Variant &p_data, Vector<uint8_t> &tmpd
 			uint32_t pos = tmpdata.size();
 			int len = a.size();
 			tmpdata.resize(tmpdata.size() + len * 4 + 8);
-			encode_uint32(TYPE_ARRAY, &tmpdata[pos + 0]);
-			encode_uint32(len, &tmpdata[pos + 4]);
+			encode_uint32(TYPE_ARRAY, &tmpdata.write[pos + 0]);
+			encode_uint32(len, &tmpdata.write[pos + 4]);
 
 			for (int i = 0; i < len; i++) {
 
 				uint32_t ofs = _pack(a[i], tmpdata, string_cache);
-				encode_uint32(ofs, &tmpdata[pos + 8 + i * 4]);
+				encode_uint32(ofs, &tmpdata.write[pos + 8 + i * 4]);
 			}
 
 			return pos;