We can throw an exception but we cannot deoptimize at a runtime call.

runtime/vm/intermediate_language.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/intermediate_language.h"
 
 #include "vm/bit_vector.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_allocator.h"
 #include "vm/flow_graph_builder.h"
@@ skipping 1158 matching lines @@
 }
 
 
 LocationSummary* ThrowInstr::MakeLocationSummary() const {
   return new LocationSummary(0, 0, LocationSummary::kCall);
 }
 
 
 
 void ThrowInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  compiler->GenerateCallRuntime(deopt_id(),
-                                token_pos(),
+  compiler->GenerateCallRuntime(token_pos(),
                                 kThrowRuntimeEntry,
                                 locs());
   __ int3();
 }
 
 
 LocationSummary* ReThrowInstr::MakeLocationSummary() const {
   return new LocationSummary(0, 0, LocationSummary::kCall);
 }
 
 
 void ReThrowInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  compiler->GenerateCallRuntime(deopt_id(),
-                                token_pos(),
+  compiler->GenerateCallRuntime(token_pos(),
                                 kReThrowRuntimeEntry,
                                 locs());
   __ int3();
 }
 
 
 LocationSummary* GotoInstr::MakeLocationSummary() const {
   return new LocationSummary(0, 0, LocationSummary::kNoCall);
 }
 
@@ skipping 165 matching lines @@
                                function(),
                                ArgumentCount(),
                                argument_names(),
                                locs());
   __ Bind(&done);
 }
 
 
 void AssertAssignableComp::EmitNativeCode(FlowGraphCompiler* compiler) {
   if (!is_eliminated()) {
-    compiler->GenerateAssertAssignable(deopt_id(),
-                                       token_pos(),
+    compiler->GenerateAssertAssignable(token_pos(),
                                        dst_type(),
                                        dst_name(),
                                        locs());
   }
   ASSERT(locs()->in(0).reg() == locs()->out().reg());
 }
 
 
 LocationSummary* BooleanNegateComp::MakeLocationSummary() const {
   return LocationSummary::Make(1,
@@ skipping 136 matching lines @@
     value->set_use_index(i);
     value->AddToEnvUseList();
   }
   instr->set_env(copy);
 }
 
 
 #undef __
 
 }  // namespace dart