VM: Avoid repeated deoptimization on speculatively hoisted smi-checks.

runtime/vm/intermediate_language.h

Index: runtime/vm/intermediate_language.h
===================================================================
--- runtime/vm/intermediate_language.h	(revision 41117)
+++ runtime/vm/intermediate_language.h	(working copy)
@@ -4615,7 +4615,11 @@
 
   virtual bool MayThrow() const { return false; }
 
+  void set_licm_hoisted(bool value) { licm_hoisted_ = value; }
+
  private:
+  bool licm_hoisted_;
+
   DISALLOW_COPY_AND_ASSIGN(CheckEitherNonSmiInstr);
 };
 
@@ -7885,8 +7889,11 @@
 
   virtual bool MayThrow() const { return false; }
 
+  void set_licm_hoisted(bool value) { licm_hoisted_ = value; }
+
  private:
   const intptr_t token_pos_;
+  bool licm_hoisted_;
 
   DISALLOW_COPY_AND_ASSIGN(CheckSmiInstr);
 };