Generate some intrinsics using our IR.

runtime/vm/assembler_x64.cc

Index: runtime/vm/assembler_x64.cc
===================================================================
--- runtime/vm/assembler_x64.cc	(revision 39651)
+++ runtime/vm/assembler_x64.cc	(working copy)
@@ -25,7 +25,8 @@
       object_pool_(GrowableObjectArray::Handle()),
       patchable_pool_entries_(),
       prologue_offset_(-1),
-      comments_() {
+      comments_(),
+      allow_constant_pool_(true) {
   // Far branching mode is only needed and implemented for MIPS and ARM.
   ASSERT(!use_far_branches);
   Isolate* isolate = Isolate::Current();
@@ -2589,6 +2590,8 @@
 
 
 bool Assembler::CanLoadFromObjectPool(const Object& object) {
+  if (!allow_constant_pool()) return false;
+
   // TODO(zra, kmillikin): Also load other large immediates from the object
   // pool
   if (object.IsSmi()) {
@@ -2672,6 +2675,7 @@
 
 
 bool Assembler::CanLoadImmediateFromPool(const Immediate& imm, Register pp) {
+  if (!allow_constant_pool()) return false;
   return !imm.is_int32() &&
          (pp != kNoRegister) &&
          (Isolate::Current() != Dart::vm_isolate());