Fix for issue 349: Make initial boundary check for BM text search.

src/runtime.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2017 matching lines @@
                              int idx) {
   int n = subject.length();
   int m = pattern.length();
   // Only preprocess at most kBMMaxShift last characters of pattern.
   int start = m < kBMMaxShift ? 0 : m - kBMMaxShift;
 
   // Build the Good Suffix table and continue searching.
   BoyerMoorePopulateGoodSuffixTable(pattern, start);
   pchar last_char = pattern[m - 1];
   // Continue search from i.
-  do {
+  while (idx <= n - m) {
     int j = m - 1;
     schar c;
     while (last_char != (c = subject[idx + j])) {
       int shift = j - CharOccurrence<schar, pchar>(c);
       idx += shift;
       if (idx > n - m) {
         return -1;
       }
     }
     while (j >= 0 && pattern[j] == (c = subject[idx + j])) j--;
     if (j < 0) {
       return idx;
     } else if (j < start) {
       // we have matched more than our tables allow us to be smart about.
       // Fall back on BMH shift.
       idx += m - 1 - CharOccurrence<schar, pchar>(last_char);
     } else {
       int gs_shift = bmgs_buffers.shift(j + 1);       // Good suffix shift.
       int bc_occ = CharOccurrence<schar, pchar>(c);
       int shift = j - bc_occ;                         // Bad-char shift.
       if (gs_shift > shift) {
         shift = gs_shift;
       }
       idx += shift;
     }
-  } while (idx <= n - m);
+  }
 
   return -1;
 }
 
 
 template <typename schar>
 static int SingleCharIndexOf(Vector<const schar> string,
                              schar pattern_char,
                              int start_index) {
   for (int i = start_index, n = string.length(); i < n; i++) {
@@ skipping 4952 matching lines @@
   } else {
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     Counters::gc_last_resort_from_js.Increment();
     Heap::CollectAllGarbage();
   }
 }
 
 
 } }  // namespace v8::internal