Tweak Mir2Lir::GenInstanceofCallingHelper for X86

Make this virtual, and split out the X86 logic.  Take advantage of SETcc
instruction for X86.

I don't think I can do much more due to need to preserve arguments for
the calls.

Change-Id: I10e3eaa61b61ceac384267e3078bb6f75c37cee4
Signed-off-by: Mark Mendell <mark.p.mendell@intel.com>
diff --git a/compiler/dex/quick/mir_to_lir.h b/compiler/dex/quick/mir_to_lir.h
index 3a68044..37990e8 100644
--- a/compiler/dex/quick/mir_to_lir.h
+++ b/compiler/dex/quick/mir_to_lir.h
@@ -1046,13 +1046,13 @@
 
     void AddSlowPath(LIRSlowPath* slowpath);
 
-  private:
-    void GenInstanceofCallingHelper(bool needs_access_check, bool type_known_final,
-                                    bool type_known_abstract, bool use_declaring_class,
-                                    bool can_assume_type_is_in_dex_cache,
-                                    uint32_t type_idx, RegLocation rl_dest,
-                                    RegLocation rl_src);
+    virtual void GenInstanceofCallingHelper(bool needs_access_check, bool type_known_final,
+                                            bool type_known_abstract, bool use_declaring_class,
+                                            bool can_assume_type_is_in_dex_cache,
+                                            uint32_t type_idx, RegLocation rl_dest,
+                                            RegLocation rl_src);
 
+  private:
     void ClobberBody(RegisterInfo* p);
     void ResetDefBody(RegisterInfo* p) {
       p->def_start = NULL;