Avoid copying

6 files changed, 24 insertions, 20 deletions

diff --git a/document/src/vespa/document/base/fieldpath.cpp b/document/src/vespa/document/base/fieldpath.cpp
index 7d861dc782b..b173d393316 100644
--- a/document/src/vespa/document/base/fieldpath.cpp
+++ b/document/src/vespa/document/base/fieldpath.cpp
@@ -183,8 +183,10 @@ FieldPath::FieldPath(const FieldPath &) = default;
 FieldPath & FieldPath::operator=(const FieldPath &) = default;
 FieldPath::~FieldPath() { }
 
-FieldPath::iterator FieldPath::insert(iterator pos, FieldPathEntry && entry) { return _path.insert(pos, std::move(entry)); }
-void FieldPath::push_back(FieldPathEntry && entry) { _path.push_back(std::move(entry)); }
+FieldPath::iterator FieldPath::insert(iterator pos, std::unique_ptr<FieldPathEntry> entry) {
+    return _path.insert(pos, vespalib::CloneablePtr<FieldPathEntry>(entry.release()));
+}
+void FieldPath::push_back(std::unique_ptr<FieldPathEntry> entry) { _path.emplace_back(entry.release()); }
 void FieldPath::pop_back() { _path.pop_back(); }
 void FieldPath::clear() { _path.clear(); }
 void FieldPath::reserve(size_t sz) { _path.reserve(sz); }
diff --git a/document/src/vespa/document/base/fieldpath.h b/document/src/vespa/document/base/fieldpath.h
index 00dad12581a..d2a60ebfbed 100644
--- a/document/src/vespa/document/base/fieldpath.h
+++ b/document/src/vespa/document/base/fieldpath.h
@@ -67,6 +67,8 @@ public:
     */
     FieldPathEntry(const DataType & dataType, const vespalib::stringref & variableName);
 
+    FieldPathEntry * clone() const { return new FieldPathEntry(*this); }
+
     Type getType() const { return _type; }
     const vespalib::string & getName() const { return _name; }
 
@@ -106,7 +108,7 @@ private:
 //typedef std::deque<FieldPathEntry> FieldPath;
 // Facade over FieldPathEntry container that exposes cloneability
 class FieldPath {
-    typedef std::vector<FieldPathEntry> Container;
+    typedef std::vector<vespalib::CloneablePtr<FieldPathEntry>> Container;
 public:
     typedef Container::reference reference;
     typedef Container::const_reference const_reference;
@@ -128,8 +130,8 @@ public:
         : _path(first, last)
     { }
 
-    iterator insert(iterator pos, FieldPathEntry && entry);
-    void push_back(FieldPathEntry && entry);
+    iterator insert(iterator pos, std::unique_ptr<FieldPathEntry> entry);
+    void push_back(std::unique_ptr<FieldPathEntry> entry);
 
     iterator begin() { return _path.begin(); }
     iterator end() { return _path.end(); }
@@ -140,10 +142,10 @@ public:
     const_reverse_iterator rbegin() const { return _path.rbegin(); }
     const_reverse_iterator rend() const { return _path.rend(); }
 
-    reference front() { return _path.front(); }
-    const_reference front() const { return _path.front(); }
-    reference back() { return _path.back(); }
-    const_reference back() const { return _path.back(); }
+    FieldPathEntry & front() { return *_path.front(); }
+    const FieldPathEntry & front() const { return *_path.front(); }
+    FieldPathEntry & back() { return *_path.back(); }
+    const FieldPathEntry & back() const { return *_path.back(); }
 
     void pop_back();
     void clear();
@@ -151,9 +153,9 @@ public:
 
     Container::size_type size() const { return _path.size(); }
     bool empty() const { return _path.empty(); }
-    reference operator[](Container::size_type i) { return _path[i]; }
+    FieldPathEntry & operator[](Container::size_type i) { return *_path[i]; }
 
-    const_reference operator[](Container::size_type i) const { return _path[i]; }
+    const FieldPathEntry & operator[](Container::size_type i) const { return *_path[i]; }
 
     void visitMembers(vespalib::ObjectVisitor &visitor) const;
 
@@ -164,7 +166,7 @@ public:
         Range(IT begin_, IT end_) : _begin(begin_), _end(end_) { }
         Range next() const { return Range(_begin+1, _end); }
         bool atEnd() const { return _begin == _end; }
-        const FieldPathEntry & cur() { return *_begin; }
+        const FieldPathEntry & cur() { return **_begin; }
     private:
         IT _begin;
         IT _end;
diff --git a/document/src/vespa/document/datatype/arraydatatype.cpp b/document/src/vespa/document/datatype/arraydatatype.cpp
index 8a4b39ecbff..5ced6053b05 100644
--- a/document/src/vespa/document/datatype/arraydatatype.cpp
+++ b/document/src/vespa/document/datatype/arraydatatype.cpp
@@ -58,9 +58,9 @@ ArrayDataType::onBuildFieldPath(FieldPath & path, const vespalib::stringref & re
             getNestedType().buildFieldPath(path, remainFieldName.substr(pos));
 
             if (remainFieldName[1] == '$') {
-                path.insert(path.begin(), FieldPathEntry(getNestedType(), remainFieldName.substr(2, endPos - 2)));
+                path.insert(path.begin(), std::make_unique<FieldPathEntry>(getNestedType(), remainFieldName.substr(2, endPos - 2)));
             } else {
-                path.insert(path.begin(), FieldPathEntry(getNestedType(), atoi(remainFieldName.substr(1, endPos - 1).c_str())));
+                path.insert(path.begin(), std::make_unique<FieldPathEntry>(getNestedType(), atoi(remainFieldName.substr(1, endPos - 1).c_str())));
             }
         }
     } else {
diff --git a/document/src/vespa/document/datatype/mapdatatype.cpp b/document/src/vespa/document/datatype/mapdatatype.cpp
index ee345040a24..6eece4e487d 100644
--- a/document/src/vespa/document/datatype/mapdatatype.cpp
+++ b/document/src/vespa/document/datatype/mapdatatype.cpp
@@ -67,11 +67,11 @@ MapDataType::buildFieldPathImpl(FieldPath & path, const DataType &dataType,
         valueType.buildFieldPath(path, (rest[0] == '.') ? rest.substr(1) : rest);
 
         if (remainFieldName[1] == '$') {
-            path.insert(path.begin(), FieldPathEntry(valueType, keyValue.substr(1)));
+            path.insert(path.begin(), std::make_unique<FieldPathEntry>(valueType, keyValue.substr(1)));
         } else {
             FieldValue::UP fv = keyType.createFieldValue();
             *fv = keyValue;
-            path.insert(path.begin(), FieldPathEntry(valueType, dataType, std::move(fv)));
+            path.insert(path.begin(), std::make_unique<FieldPathEntry>(valueType, dataType, std::move(fv)));
         }
     } else if (memcmp(remainFieldName.c_str(), "key", 3) == 0) {
         size_t endPos = 3;
@@ -81,7 +81,7 @@ MapDataType::buildFieldPathImpl(FieldPath & path, const DataType &dataType,
 
         keyType.buildFieldPath(path, remainFieldName.substr(endPos));
 
-        path.insert(path.begin(), FieldPathEntry(dataType, keyType, valueType, true, false));
+        path.insert(path.begin(), std::make_unique<FieldPathEntry>(dataType, keyType, valueType, true, false));
     } else if (memcmp(remainFieldName.c_str(), "value", 5) == 0) {
         size_t endPos = 5;
         if (remainFieldName[endPos] == '.') {
@@ -90,7 +90,7 @@ MapDataType::buildFieldPathImpl(FieldPath & path, const DataType &dataType,
 
         valueType.buildFieldPath(path, remainFieldName.substr(endPos));
 
-        path.insert(path.begin(), FieldPathEntry(dataType, keyType, valueType, false, true));
+        path.insert(path.begin(), std::make_unique<FieldPathEntry>(dataType, keyType, valueType, false, true));
     } else {
         keyType.buildFieldPath(path, remainFieldName);
     }
diff --git a/document/src/vespa/document/datatype/structureddatatype.cpp b/document/src/vespa/document/datatype/structureddatatype.cpp
index 748da0efa50..e054cf24706 100644
--- a/document/src/vespa/document/datatype/structureddatatype.cpp
+++ b/document/src/vespa/document/datatype/structureddatatype.cpp
@@ -79,7 +79,7 @@ StructuredDataType::onBuildFieldPath(FieldPath & path, const vespalib::stringref
         const document::Field &fp = getField(currFieldName);
         fp.getDataType().buildFieldPath(path, subFieldName);
 
-        path.insert(path.begin(), FieldPathEntry(fp));
+        path.insert(path.begin(), std::make_unique<FieldPathEntry>(fp));
     } else {
         throw FieldNotFoundException(currFieldName, make_string("Invalid field path '%s', no field named '%s'",
                                                    remainFieldName.c_str(), currFieldName.c_str()));
diff --git a/document/src/vespa/document/update/fieldpathupdate.cpp b/document/src/vespa/document/update/fieldpathupdate.cpp
index 256439a039b..7265329d4d5 100644
--- a/document/src/vespa/document/update/fieldpathupdate.cpp
+++ b/document/src/vespa/document/update/fieldpathupdate.cpp
@@ -113,7 +113,7 @@ FieldPathUpdate::getResultingDataType(const FieldPath & path) const
     if (path.empty()) {
         throw vespalib::IllegalStateException("Cannot get resulting data type from an empty field path", VESPA_STRLOC);
     }
-    return path.rbegin()->getDataType();
+    return path.back().getDataType();
 }
 
 vespalib::string