Refactoring of RegExp interface to better support calling several times in a row.

src/x64/codegen-x64.cc

 // Copyright 2010 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 7164 matching lines @@
   Label next_capture, done;
   __ movq(rax, Operand(rsp, kPreviousIndexOffset));
   // Capture register counter starts from number of capture registers and
   // counts down until wraping after zero.
   __ bind(&next_capture);
   __ subq(rdx, Immediate(1));
   __ j(negative, &done);
   // Read the value from the static offsets vector buffer and make it a smi.
   __ movl(rdi, Operand(rcx, rdx, times_int_size, 0));
   __ Integer32ToSmi(rdi, rdi, &runtime);
-  // Add previous index (from its stack slot) if value is not negative.
-  Label capture_negative;
-  // Negative flag set by smi convertion above.
-  __ j(negative, &capture_negative);
-  __ SmiAdd(rdi, rdi, rax, &runtime);  // Add previous index.
-  __ bind(&capture_negative);
   // Store the smi value in the last match info.
   __ movq(FieldOperand(rbx,
                        rdx,
                        times_pointer_size,
                        RegExpImpl::kFirstCaptureOffset),
                        rdi);
   __ jmp(&next_capture);
   __ bind(&done);
 
   // Return last match info.
@@ skipping 2685 matching lines @@
   // Call the function from C++.
   return FUNCTION_CAST<ModuloFunction>(buffer);
 }
 
 #endif
 
 
 #undef __
 
 } }  // namespace v8::internal