Introduce StringImpl::createPreallocatedStatic

third_party/WebKit/Source/build/scripts/templates/MakeNames.cpp.tmpl

Index: third_party/WebKit/Source/build/scripts/templates/MakeNames.cpp.tmpl
diff --git a/third_party/WebKit/Source/build/scripts/templates/MakeNames.cpp.tmpl b/third_party/WebKit/Source/build/scripts/templates/MakeNames.cpp.tmpl
index ed0c03160f41f7ef42c01dc3f783c5c1a13ca419..2889987e7c57729a48b468e122b132a98c7dd274 100644
--- a/third_party/WebKit/Source/build/scripts/templates/MakeNames.cpp.tmpl
+++ b/third_party/WebKit/Source/build/scripts/templates/MakeNames.cpp.tmpl
@@ -27,20 +27,25 @@ const AtomicString& {{entry|symbol}} = reinterpret_cast<AtomicString*>(&{{suffix
 
 void init{{suffix}}()
 {
+    const int kMaxNameLength = {{entries|map(attribute='name')|map('length')|max}} + 1;
     struct NameEntry {
-        const char* name;
+        // StringImpl instances are created at |stringImplStorage| in-place.
+        // |name| must be placed soon after |stringImplStorage| to match the memory layout requirement of StringImpl.
+        char stringImplStorage[sizeof(StringImpl)];
+        char name[kMaxNameLength];
         unsigned hash;
         unsigned char length;
     };
 
-    static const NameEntry kNames[] = {
+    static NameEntry kNames[] = {
     {% for entry in entries|sort(attribute='name', case_sensitive=True) %}
-        { "{{entry|cpp_name}}", {{entry|cpp_name|hash}}, {{entry|cpp_name|length}} },
+        { "", "{{entry|cpp_name}}", {{entry|cpp_name|hash}}, {{entry|cpp_name|length}} },
     {% endfor %}
     };
 
     for (size_t i = 0; i < WTF_ARRAY_LENGTH(kNames); i++) {
-        StringImpl* stringImpl = StringImpl::createStatic(kNames[i].name, kNames[i].length, kNames[i].hash);
+        StringImpl* stringImpl = StringImpl::createPreallocatedStatic(kNames[i].stringImplStorage, kNames[i].length, kNames[i].hash);
+        ASSERT(reinterpret_cast<char*>(stringImpl + 1) == kNames[i].name);
         void* address = reinterpret_cast<AtomicString*>(&{{suffix}}NamesStorage) + i;
         new (address) AtomicString(stringImpl);
     }