Rewrite base::JSONReader to be 35-40% faster, depending on the input string.

base/string_util.cc

Index: base/string_util.cc
diff --git a/base/string_util.cc b/base/string_util.cc
index 2b9e1bcda47743f7a823954442799e7d9b345af7..0c7701c25edc58ffc74c1b9d25d186b399c6f4ef 100644
--- a/base/string_util.cc
+++ b/base/string_util.cc
@@ -475,8 +475,15 @@ bool IsStringUTF8(const std::string& str) {
   while (char_index < src_len) {
     int32 code_point;
     CBU8_NEXT(src, char_index, src_len, code_point);
-    if (!base::IsValidCharacter(code_point))
-       return false;
+    if (!base::IsValidCharacter(code_point)) {
+      for (size_t i = 0; i < str.length(); ++i) {

[Mark Mentovai, 2012/05/08 20:19:41]

Dump the debugging code.

[Robert Sesek, 2012/05/15 16:57:51]

Done.

+        printf("0x%x ", str[i]);
+      }
+      printf("\n");
+      LOG(INFO) << "STRING = <<<" << str << ">>>";
+      LOG(INFO) << "**** char_index = " << char_index << " // " << code_point;
+      return false;
+    }
   }
   return true;
 }