[builtins] Move StringIndexOf to a builtin.

src/runtime/runtime-strings.cc

 // Copyright 2014 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/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/regexp/jsregexp-inl.h"
 #include "src/string-builder.h"
 #include "src/string-search.h"
@@ skipping 25 matching lines @@
     Handle<String> new_second;
     if (!StringReplaceOneCharWithString(isolate, second, search, replace, found,
                                         recursion_limit)
              .ToHandle(&new_second)) {
       return MaybeHandle<String>();
     }
     if (*found) return isolate->factory()->NewConsString(first, new_second);
 
     return subject;
   } else {
-    int index = String::IndexOf(isolate, subject, search, 0);
-    if (index == -1) return subject;
+    Object* index = String::IndexOf(isolate, subject, search,
+                                    isolate->factory()->undefined_value());
+    int index_int = -1;
+    index->ToInt32(&index_int);
+
+    if (index_int == -1) return subject;
     *found = true;
-    Handle<String> first = isolate->factory()->NewSubString(subject, 0, index);
+    Handle<String> first =
+        isolate->factory()->NewSubString(subject, 0, index_int);
     Handle<String> cons1;
     ASSIGN_RETURN_ON_EXCEPTION(
         isolate, cons1, isolate->factory()->NewConsString(first, replace),
         String);
-    Handle<String> second =
-        isolate->factory()->NewSubString(subject, index + 1, subject->length());
+    Handle<String> second = isolate->factory()->NewSubString(
+        subject, index_int + 1, subject->length());
     return isolate->factory()->NewConsString(cons1, second);
   }
 }
 
 
 RUNTIME_FUNCTION(Runtime_StringReplaceOneCharWithString) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 3);
   CONVERT_ARG_HANDLE_CHECKED(String, subject, 0);
   CONVERT_ARG_HANDLE_CHECKED(String, search, 1);
@@ skipping 17 matching lines @@
   }
   if (isolate->has_pending_exception()) return isolate->heap()->exception();
   // In case of empty handle and no pending exception we have stack overflow.
   return isolate->StackOverflow();
 }
 
 
 RUNTIME_FUNCTION(Runtime_StringIndexOf) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 3);
-
-  CONVERT_ARG_HANDLE_CHECKED(String, sub, 0);
-  CONVERT_ARG_HANDLE_CHECKED(String, pat, 1);
-  CONVERT_ARG_HANDLE_CHECKED(Object, index, 2);
-
-  uint32_t start_index = 0;
-  if (!index->ToArrayIndex(&start_index)) return Smi::FromInt(-1);
-
-  CHECK(start_index <= static_cast<uint32_t>(sub->length()));
-  int position = String::IndexOf(isolate, sub, pat, start_index);
-  return Smi::FromInt(position);
+  return String::IndexOf(isolate, args.at<Object>(0), args.at<Object>(1),
+                         args.at<Object>(2));
 }
 
 RUNTIME_FUNCTION(Runtime_StringLastIndexOf) {
   HandleScope handle_scope(isolate);
   return String::LastIndexOf(isolate, args.at<Object>(0), args.at<Object>(1),
                              isolate->factory()->undefined_value());
 }
 
 RUNTIME_FUNCTION(Runtime_SubString) {
   HandleScope scope(isolate);
@@ skipping 932 matching lines @@
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 2);
   if (!args[0]->IsString()) return isolate->heap()->undefined_value();
   if (!args[1]->IsNumber()) return isolate->heap()->undefined_value();
   if (std::isinf(args.number_at(1))) return isolate->heap()->nan_value();
   return __RT_impl_Runtime_StringCharCodeAtRT(args, isolate);
 }
 
 }  // namespace internal
 }  // namespace v8