MIPS: port Fix for a possible bug in RegExp stack guard.

Ported r9058 (43f127bd)

BUG=
TEST=

Review URL: http://codereview.chromium.org/7776027

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9074 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

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

@@ -1050,7 +1050,7 @@ int RegExpMacroAssemblerMIPS::CheckStackGuardState(Address* return_address,
   MaybeObject* result = Execution::HandleStackGuardInterrupt();
 
   if (*code_handle != re_code) {  // Return address no longer valid.
-    int delta = *code_handle - re_code;
+    int delta = code_handle->address() - re_code->address();
     // Overwrite the return address on the stack.
     *return_address += delta;
   }