Generate some intrinsics using our IR.

runtime/vm/intermediate_language_arm64.cc

Index: runtime/vm/intermediate_language_arm64.cc
===================================================================
--- runtime/vm/intermediate_language_arm64.cc	(revision 39909)
+++ runtime/vm/intermediate_language_arm64.cc	(working copy)
@@ -61,7 +61,7 @@
     } else {
       ASSERT(value.IsStackSlot());
       const intptr_t value_offset = value.ToStackSlotOffset();
-      __ LoadFromOffset(TMP, FP, value_offset, PP);
+      __ LoadFromOffset(TMP, value.base_reg(), value_offset, PP);
       __ Push(TMP);
     }
   }
@@ -85,6 +85,13 @@
 void ReturnInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   const Register result = locs()->in(0).reg();
   ASSERT(result == R0);
+
+  if (compiler->intrinsic_mode()) {
+    // Intrinsics don't have a frame.
+    __ ret();
+    return;
+  }
+
 #if defined(DEBUG)
   Label stack_ok;
   __ Comment("Stack Check");
@@ -1575,10 +1582,12 @@
  public:
   BoxAllocationSlowPath(Instruction* instruction,
                         const Class& cls,
-                        Register result)
+                        Register result,
+                        bool is_intrinsic)
       : instruction_(instruction),
         cls_(cls),
-        result_(result) { }
+        result_(result),
+        is_intrinsic_(is_intrinsic) { }
 
   virtual void EmitNativeCode(FlowGraphCompiler* compiler) {
     Isolate* isolate = compiler->isolate();
@@ -1591,6 +1600,10 @@
     }
     __ Bind(entry_label());
 
+    if (is_intrinsic_) {
+      __ EnterStubFrame(true);
+    }
+
     const Code& stub =
         Code::Handle(isolate, stub_code->GetAllocationStubForClass(cls_));
     const ExternalLabel label(stub.EntryPoint());
@@ -1607,6 +1620,9 @@
     __ mov(result_, R0);
     compiler->RestoreLiveRegisters(locs);
 
+    if (is_intrinsic_) {
+      __ LeaveStubFrame();
+    }
     __ b(exit_label());
   }
 
@@ -1616,7 +1632,8 @@
                        Register result,
                        Register temp) {
     BoxAllocationSlowPath* slow_path =
-        new BoxAllocationSlowPath(instruction, cls, result);
+        new BoxAllocationSlowPath(instruction, cls, result,
+                                  compiler->intrinsic_mode());
     compiler->AddSlowPathCode(slow_path);
 
     __ TryAllocate(cls,
@@ -1631,6 +1648,7 @@
   Instruction* instruction_;
   const Class& cls_;
   Register result_;
+  bool is_intrinsic_;
 };