Disable reg-exp compilation in background via a flag

runtime/vm/compiler.cc

Index: runtime/vm/compiler.cc
diff --git a/runtime/vm/compiler.cc b/runtime/vm/compiler.cc
index 5b67de0488728362a0a9205fa30cd2a2c3a7cb68..aaf0787fc23f6858bb842c94bac689beebc6bb81 100644
--- a/runtime/vm/compiler.cc
+++ b/runtime/vm/compiler.cc
@@ -518,28 +518,20 @@ void CompileParsedFunctionHelper::FinalizeCompilation(
     }
 
     // Register code with the classes it depends on because of CHA and
-    // fields it depends on because of store guards.
-    // Deoptimize field dependent code first, before registering
-    // this yet uninstalled code as dependent on a field.
-    // TODO(srdjan): Debugging dart2js crashes;
-    // FlowGraphOptimizer::VisitStoreInstanceField populates
-    // deoptimize_dependent_code() list, currently disabled.
-    for (intptr_t i = 0;
-         i < flow_graph->deoptimize_dependent_code().length();
-         i++) {
-      const Field* field = flow_graph->deoptimize_dependent_code()[i];
-      field->DeoptimizeDependentCode();
-    }
-    for (intptr_t i = 0;
-         i < thread()->cha()->leaf_classes().length();
-         ++i) {
-      thread()->cha()->leaf_classes()[i]->RegisterCHACode(code);
-    }
-    for (intptr_t i = 0;
-         i < flow_graph->guarded_fields()->length();
-         i++) {
-      const Field* field = (*flow_graph->guarded_fields())[i];
-      field->RegisterDependentCode(code);
+    // fields it depends on because of store guards, unless we cannot
+    // deopt.
+    if (!FLAG_precompilation) {

[rmacnak, 2016/02/09 20:26:11]

Always true as precompiled code doesn't go through here anymore. It goes through
the FinalizeCompilation in precompiler.cc instead.

[srdjan, 2016/02/09 20:44:43]

Thanks, that was a sync issue,.

+      for (intptr_t i = 0;
+           i < thread()->cha()->leaf_classes().length();
+           ++i) {
+        thread()->cha()->leaf_classes()[i]->RegisterCHACode(code);
+      }
+      for (intptr_t i = 0;
+           i < flow_graph->guarded_fields()->length();
+           i++) {
+        const Field* field = (*flow_graph->guarded_fields())[i];
+        field->RegisterDependentCode(code);
+      }
     }
   } else {  // not optimized.
     if (function.ic_data_array() == Array::null()) {
@@ -1325,8 +1317,11 @@ RawError* Compiler::CompileOptimizedFunction(Thread* thread,
 
   // Optimization must happen in non-mutator/Dart thread if background
   // compilation is on. OSR compilation still occurs in the main thread.
+  // TODO(Srdjan): Remove assert allowance for regular expression functions
+  // once they can be compiled in background.
   ASSERT((osr_id != kNoOSRDeoptId) || !FLAG_background_compilation ||
-         !thread->IsMutatorThread());
+         !thread->IsMutatorThread() ||
+         function.IsIrregexpFunction());
   CompilationPipeline* pipeline =
       CompilationPipeline::New(thread->zone(), function);
   return CompileFunctionHelper(pipeline,