VM: Fix precompiler running with multiple iterations.

runtime/vm/precompiler.cc

 // Copyright (c) 2015, 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/precompiler.h"
 
 #include "vm/aot_optimizer.h"
 #include "vm/assembler.h"
 #include "vm/ast_printer.h"
 #include "vm/branch_optimizer.h"
@@ skipping 750 matching lines @@
       AddConstObject(Instance::Cast(value));
     }
 
     if (field.has_initializer()) {
       // Should not be in the middle of initialization while precompiling.
       ASSERT(value.raw() != Object::transition_sentinel().raw());
 
       const bool is_initialized = value.raw() != Object::sentinel().raw();
       if (is_initialized && !reset_fields_) return;
 
-      if (!field.HasPrecompiledInitializer()) {
+      if (!field.HasPrecompiledInitializer() ||
+          !Function::Handle(Z, field.PrecompiledInitializer()).HasCode()) {
         if (FLAG_trace_precompiler) {
           THR_Print("Precompiling initializer for %s\n", field.ToCString());
         }
         ASSERT(Dart::snapshot_kind() != Snapshot::kAppNoJIT);
-        field.SetStaticValue(Instance::Handle(field.SavedInitialStaticValue()));
         const Function& initializer =
             Function::Handle(CompileStaticInitializer(field));

[rmacnak, 2016/05/10 19:43:04]

Handle(Z, ...

[Florian Schneider, 2016/05/10 19:49:59]

Done.

-        if (!initializer.IsNull()) {
-          field.SetPrecompiledInitializer(initializer);
-        }
-        ASSERT(field.HasPrecompiledInitializer());
-        const Function& function =
-            Function::Handle(Z, field.PrecompiledInitializer());
-        AddCalleesOf(function);
+        ASSERT(!initializer.IsNull());
+        field.SetPrecompiledInitializer(initializer);
+        AddCalleesOf(initializer);
       }
     }
   }
 }
 
 
 RawFunction* Precompiler::CompileStaticInitializer(const Field& field) {
   ASSERT(field.is_static());
   ASSERT(!field.HasPrecompiledInitializer());
   Thread* thread = Thread::Current();
@@ skipping 1971 matching lines @@
       CompilationPipeline::New(thread->zone(), function);
 
   ASSERT(FLAG_precompiled_mode);
   const bool optimized = function.IsOptimizable();  // False for natives.
   return PrecompileFunctionHelper(pipeline, function, optimized);
 }
 
 #endif  // DART_PRECOMPILER
 
 }  // namespace dart