Direct call to native RegExp code from JavaScript

src/x64/regexp-macro-assembler-x64.cc

Index: src/x64/regexp-macro-assembler-x64.cc
===================================================================
--- src/x64/regexp-macro-assembler-x64.cc	(revision 3531)
+++ src/x64/regexp-macro-assembler-x64.cc	(working copy)
@@ -67,13 +67,17 @@
  *
  * The stack will have the following content, in some order, indexable from the
  * frame pointer (see, e.g., kStackHighEnd):
- *    - stack_area_base       (High end of the memory area to use as
- *                             backtracking stack)
- *    - at_start              (if 1, start at start of string, if 0, don't)
- *    - int* capture_array    (int[num_saved_registers_], for output).
- *    - end of input          (Address of end of string)
- *    - start of input        (Address of first character in string)
- *    - String** input_string (location of a handle containing the string)
+ *    - direct_call          (if 1, direct call from JavaScript code, if 0 call
+ *                            through the runtime system)
+ *    - stack_area_base      (High end of the memory area to use as
+ *                            backtracking stack)
+ *    - at_start             (if 1, we are starting at the start of the
+ *                            string, otherwise 0)
+ *    - int* capture_array   (int[num_saved_registers_], for output).
+ *    - end of input         (Address of end of string)
+ *    - start of input       (Address of first character in string)
+ *    - start index          (character index of start)
+ *    - String* input_string (input string)
  *    - return address
  *    - backup of callee save registers (rbx, possibly rsi and rdi).
  *    - Offset of location before start of input (effectively character
@@ -90,11 +94,13 @@
  * calling the code's entry address cast to a function pointer with the
  * following signature:
  * int (*match)(String* input_string,
+ *              int start_index,
  *              Address start,
  *              Address end,
  *              int* capture_output_array,
  *              bool at_start,
- *              byte* stack_area_base)
+ *              byte* stack_area_base,
+ *              bool direct_call)
  */
 
 #define __ ACCESS_MASM(masm_)