Unbox phis that were proven to be of type Double.

runtime/vm/intermediate_language_test.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/unit_test.h"
 
 namespace dart {
 
 TEST_CASE(InstructionTests) {
   TargetEntryInstr* target_instr =
       new TargetEntryInstr(CatchClauseNode::kInvalidTryIndex);
   EXPECT(target_instr->IsBlockEntry());
   EXPECT(!target_instr->IsBind());
   BindInstr* bind_instr =
       new BindInstr(BindInstr::kUnused, new CurrentContextComp());
   EXPECT(bind_instr->IsBind());
   EXPECT(!bind_instr->IsBlockEntry());
 }
 
 
 TEST_CASE(OptimizationTests) {
-  Definition* def1 = new PhiInstr(0);
-  Definition* def2 = new PhiInstr(0);
+  JoinEntryInstr* join =
+      new JoinEntryInstr(CatchClauseNode::kInvalidTryIndex);
+
+  Definition* def1 = new PhiInstr(join, 0);
+  Definition* def2 = new PhiInstr(join, 0);
   Value* use1a = new Value(def1);
   Value* use1b = new Value(def1);
   EXPECT(use1a->Equals(use1b));
   Value* use2 = new Value(def2);
   EXPECT(!use2->Equals(use1a));
 
   ConstantComp* c1 = new ConstantComp(Bool::ZoneHandle(Bool::True()));
   ConstantComp* c2 = new ConstantComp(Bool::ZoneHandle(Bool::True()));
   EXPECT(c1->Equals(c2));
   ConstantComp* c3 = new ConstantComp(Object::ZoneHandle());
   ConstantComp* c4 = new ConstantComp(Object::ZoneHandle());
   EXPECT(c3->Equals(c4));
   EXPECT(!c3->Equals(c1));
 }
 
 }  // namespace dart