Parser: Delay internalizing strings and values.

src/func-name-inferrer.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/ast.h"
+#include "src/ast-value-factory.h"
 #include "src/func-name-inferrer.h"
 #include "src/list-inl.h"
 
 namespace v8 {
 namespace internal {
 
-FuncNameInferrer::FuncNameInferrer(Isolate* isolate, Zone* zone)
-    : isolate_(isolate),
+FuncNameInferrer::FuncNameInferrer(AstValueFactory* ast_value_factory,
+                                   Zone* zone)
+    : ast_value_factory_(ast_value_factory),
       entries_stack_(10, zone),
       names_stack_(5, zone),
       funcs_to_infer_(4, zone),
       zone_(zone) {
 }
 
 
-void FuncNameInferrer::PushEnclosingName(Handle<String> name) {
+void FuncNameInferrer::PushEnclosingName(const AstString* name) {
   // Enclosing name is a name of a constructor function. To check
   // that it is really a constructor, we check that it is not empty
   // and starts with a capital letter.
-  if (name->length() > 0 && Runtime::IsUpperCaseChar(
-          isolate()->runtime_state(), name->Get(0))) {
+  if (!name->IsEmpty() && unibrow::Uppercase::Is(name->FirstCharacter())) {
     names_stack_.Add(Name(name, kEnclosingConstructorName), zone());
   }
 }
 
 
-void FuncNameInferrer::PushLiteralName(Handle<String> name) {
-  if (IsOpen() &&
-      !String::Equals(isolate()->factory()->prototype_string(), name)) {
+void FuncNameInferrer::PushLiteralName(const AstString* name) {
+  if (IsOpen() && name != ast_value_factory_->prototype_string()) {
     names_stack_.Add(Name(name, kLiteralName), zone());
   }
 }
 
 
-void FuncNameInferrer::PushVariableName(Handle<String> name) {
-  if (IsOpen() &&
-      !String::Equals(isolate()->factory()->dot_result_string(), name)) {
+void FuncNameInferrer::PushVariableName(const AstString* name) {
+  if (IsOpen() && name != ast_value_factory_->dot_result_string()) {
     names_stack_.Add(Name(name, kVariableName), zone());
   }
 }
 
 
-Handle<String> FuncNameInferrer::MakeNameFromStack() {
-  return MakeNameFromStackHelper(0, isolate()->factory()->empty_string());
-}
-
-
-Handle<String> FuncNameInferrer::MakeNameFromStackHelper(int pos,
-                                                         Handle<String> prev) {
-  if (pos >= names_stack_.length()) return prev;
-  if (pos < names_stack_.length() - 1 &&
-      names_stack_.at(pos).type == kVariableName &&
-      names_stack_.at(pos + 1).type == kVariableName) {
-    // Skip consecutive variable declarations.
-    return MakeNameFromStackHelper(pos + 1, prev);
+const AstString* FuncNameInferrer::MakeNameFromStack() {
+  // First see how many names we will use.
+  int length = 0;
+  bool one_byte = true;
+  int pos = 0;
+  while (pos < names_stack_.length()) {
+    if (pos < names_stack_.length() - 1 &&
+        names_stack_.at(pos).type == kVariableName &&
+        names_stack_.at(pos + 1).type == kVariableName) {
+      // Skip consecutive variable declarations.
+      ++pos;
+      continue;
+    }
+    int cur_length = names_stack_.at(pos).name->length();
+    if (length + 1 + cur_length > String::kMaxLength) {
+      break;
+    }
+    if (length == 0) {
+      length = cur_length;
+    } else {  // Add the . between names.
+      length += (1 + cur_length);
+    }
+    one_byte = one_byte && names_stack_.at(pos).name->is_one_byte();
+    ++pos;
+  }
+  const AstString* to_return = NULL;
+  const char* dot = ".";
+  if (one_byte) {
+    Vector<uint8_t> new_name = Vector<uint8_t>::New(length);
+    int name_pos = 0;
+    for (int i = 0; i < pos; ++i) {
+      if (i < names_stack_.length() - 1 &&
+          names_stack_.at(i).type == kVariableName &&
+          names_stack_.at(i + 1).type == kVariableName) {
+        // Skip consecutive variable declarations.
+        continue;
+      }
+      if (name_pos != 0) {
+        CopyChars(new_name.start() + name_pos, dot, 1);
+        ++name_pos;
+      }
+      CopyChars(new_name.start() + name_pos,
+                names_stack_.at(i).name->raw_data(),
+                names_stack_.at(i).name->length());
+      name_pos += names_stack_.at(i).name->length();
+    }
+    to_return = ast_value_factory_->GetOneByteString(Vector<const uint8_t>(
+        reinterpret_cast<const uint8_t*>(new_name.start()),
+        new_name.length()));
+    new_name.Dispose();
   } else {
-    if (prev->length() > 0) {
-      Handle<String> name = names_stack_.at(pos).name;
-      if (prev->length() + name->length() + 1 > String::kMaxLength) return prev;
-      Factory* factory = isolate()->factory();
-      Handle<String> curr =
-          factory->NewConsString(factory->dot_string(), name).ToHandleChecked();
-      curr = factory->NewConsString(prev, curr).ToHandleChecked();
-      return MakeNameFromStackHelper(pos + 1, curr);
-    } else {
-      return MakeNameFromStackHelper(pos + 1, names_stack_.at(pos).name);
+    Vector<uint16_t> new_name = Vector<uint16_t>::New(length);
+    int name_pos = 0;
+    for (int i = 0; i < pos; ++i) {
+      if (i < names_stack_.length() - 1 &&
+          names_stack_.at(i).type == kVariableName &&
+          names_stack_.at(i + 1).type == kVariableName) {
+        // Skip consecutive variable declarations.
+        continue;
+      }
+      if (name_pos != 0) {
+        CopyChars(new_name.start() + name_pos, dot, 1);
+        ++name_pos;
+      }
+      if (names_stack_.at(i).name->is_one_byte()) {
+        CopyChars(new_name.start() + name_pos,
+                  names_stack_.at(i).name->raw_data(),
+                  names_stack_.at(i).name->length());
+      } else {
+        CopyChars(new_name.start() + name_pos,
+                  reinterpret_cast<const uint16_t*>(
+                      names_stack_.at(i).name->raw_data()),
+                  names_stack_.at(i).name->length());
+      }
+      name_pos += names_stack_.at(i).name->length();
     }
+    to_return = ast_value_factory_->GetTwoByteString(Vector<const uint16_t>(
+        reinterpret_cast<const uint16_t*>(new_name.start()),
+        new_name.length()));
+    new_name.Dispose();
   }
+  return to_return;
 }
 
 
 void FuncNameInferrer::InferFunctionsNames() {
-  Handle<String> func_name = MakeNameFromStack();
+  const AstString* func_name = MakeNameFromStack();
   for (int i = 0; i < funcs_to_infer_.length(); ++i) {
-    funcs_to_infer_[i]->set_inferred_name(func_name);
+    funcs_to_infer_[i]->set_raw_inferred_name(func_name);
   }
   funcs_to_infer_.Rewind(0);
 }
 
 
 } }  // namespace v8::internal