Generate some intrinsics using our IR.

runtime/vm/flow_graph_compiler_x64.cc

Index: runtime/vm/flow_graph_compiler_x64.cc
===================================================================
--- runtime/vm/flow_graph_compiler_x64.cc	(revision 39726)
+++ runtime/vm/flow_graph_compiler_x64.cc	(working copy)
@@ -57,6 +57,20 @@
 }
 
 
+void FlowGraphCompiler::EnterIntrinsicMode() {
+  ASSERT(!intrinsic_mode());
+  intrinsic_mode_ = true;
+  assembler()->set_allow_constant_pool(false);
+}
+
+
+void FlowGraphCompiler::ExitIntrinsicMode() {
+  ASSERT(intrinsic_mode());
+  intrinsic_mode_ = false;
+  assembler()->set_allow_constant_pool(true);
+}
+
+
 RawDeoptInfo* CompilerDeoptInfo::CreateDeoptInfo(FlowGraphCompiler* compiler,
                                                  DeoptInfoBuilder* builder,
                                                  const Array& deopt_table) {
@@ -1695,12 +1709,16 @@
 }
 
 
-void ParallelMoveResolver::Exchange(Register reg, intptr_t stack_offset) {
+void ParallelMoveResolver::Exchange(Register reg,
+                                    Register base_reg,
+                                    intptr_t stack_offset) {
   UNREACHABLE();
 }
 
 
-void ParallelMoveResolver::Exchange(intptr_t stack_offset1,
+void ParallelMoveResolver::Exchange(Register base_reg1,
+                                    intptr_t stack_offset1,
+                                    Register base_reg2,
                                     intptr_t stack_offset2) {
   UNREACHABLE();
 }