Don't preparse large files to find boundaries of lazy functions.

src/scanner.h

 // Copyright 2011 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 24 matching lines @@
 #include "checks.h"
 #include "globals.h"
 #include "token.h"
 #include "unicode-inl.h"
 #include "utils.h"
 
 namespace v8 {
 namespace internal {
 
 
-// General collection of bit-flags that can be passed to scanners and
+// General collection of (multi-)bit-flags that can be passed to scanners and
 // parsers to signify their (initial) mode of operation.
 enum ParsingFlags {
   kNoParsingFlags = 0,
-  kAllowLazy = 1,
-  kAllowNativesSyntax = 2,
-  kHarmonyScoping = 4
+  // Embed LanguageMode values in parsing flags, i.e., equivalent to:
+  // CLASSIC_MODE = 0,
+  // STRICT_MODE,
+  // EXTENDED_MODE,
+  kLanguageModeMask = 0x03,
+  kAllowLazy = 4,
+  kAllowNativesSyntax = 8
 };
 
+STATIC_ASSERT((kLanguageModeMask & CLASSIC_MODE) == CLASSIC_MODE);
+STATIC_ASSERT((kLanguageModeMask & STRICT_MODE) == STRICT_MODE);
+STATIC_ASSERT((kLanguageModeMask & EXTENDED_MODE) == EXTENDED_MODE);
+
 
 // Returns the value (0 .. 15) of a hexadecimal character c.
 // If c is not a legal hexadecimal character, returns a value < 0.
 inline int HexValue(uc32 c) {
   c -= '0';
   if (static_cast<unsigned>(c) <= 9) return c;
   c = (c | 0x20) - ('a' - '0');  // detect 0x11..0x16 and 0x31..0x36.
   if (static_cast<unsigned>(c) <= 5) return c + 10;
   return -1;
 }
@@ skipping 481 matching lines @@
   // line-terminator after the current token, and before the next.
   bool has_multiline_comment_before_next_;
   // Whether we scan 'let' as a keyword for harmony block scoped
   // let bindings.
   bool harmony_scoping_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_SCANNER_H_