Generate some intrinsics using our IR.

runtime/vm/assembler_arm.h

Index: runtime/vm/assembler_arm.h
===================================================================
--- runtime/vm/assembler_arm.h	(revision 39909)
+++ runtime/vm/assembler_arm.h	(working copy)
@@ -295,7 +295,9 @@
         object_pool_(GrowableObjectArray::Handle()),
         prologue_offset_(-1),
         use_far_branches_(use_far_branches),
-        comments_() { }
+        comments_(),
+        allow_constant_pool_(true) { }
+
   ~Assembler() { }
 
   void PopRegister(Register r) { Pop(r); }
@@ -828,6 +830,13 @@
   static bool IsSafe(const Object& object) { return true; }
   static bool IsSafeSmi(const Object& object) { return object.IsSmi(); }
 
+  bool allow_constant_pool() const {
+    return allow_constant_pool_;
+  }
+  void set_allow_constant_pool(bool b) {
+    allow_constant_pool_ = b;
+  }
+
  private:
   AssemblerBuffer buffer_;  // Contains position independent code.
   GrowableObjectArray& object_pool_;  // Objects and patchable jump targets.
@@ -858,6 +867,8 @@
 
   GrowableArray<CodeComment*> comments_;
 
+  bool allow_constant_pool_;
+
   void EmitType01(Condition cond,
                   int type,
                   Opcode opcode,