KMP string search using direct memory access and templates for type specialization.

src/jsregexp.cc

Index: src/jsregexp.cc
diff --git a/src/jsregexp.cc b/src/jsregexp.cc
index 0e4dee19ded0d754c157bc1c1e3e23455dbd67c2..8425fff1e8290bdd4e5186b06da09fc1e1ce64f5 100644
--- a/src/jsregexp.cc
+++ b/src/jsregexp.cc
@@ -231,13 +231,16 @@ Handle<Object> RegExpImpl::AtomExecGlobal(Handle<JSRegExp> re,
                                           Handle<String> subject) {
   Handle<String> needle(String::cast(re->data()));
   Handle<JSArray> result = Factory::NewJSArray(1);
-  bool keep_going = true;
   int index = 0;
   int match_count = 0;
+  int subject_length = subject->length();
   int needle_length = needle->length();
-  while (keep_going) {
+  while (true) {
     LOG(RegExpExecEvent(re, index, subject));
-    int value = Runtime::StringMatchKmp(*subject, *needle, index);
+    int value = -1;
+    if (index + needle_length <= subject_length) {
+      value = Runtime::StringMatchKmp(*subject, *needle, index);
+    }
     if (value == -1) break;
     HandleScope scope;
     int end = value + needle_length;