Disable reg-exp compilation in background via a flag

runtime/vm/compiler.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/compiler.h"
 
 #include "vm/assembler.h"
 
 #include "vm/ast_printer.h"
 #include "vm/block_scheduler.h"
@@ skipping 500 matching lines @@
         ASSERT(!is_osr);  // OSR is compiled in background.
         function.InstallOptimizedCode(code, is_osr);
       }
       if (function.usage_counter() < 0) {
         // Reset to 0 so that it can be recompiled if needed.
         function.set_usage_counter(0);
       }
     }
 
     // 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();
-    }
+    // fields it depends on because of store guards, unless we cannot
+    // deopt.
     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);
@@ skipping 775 matching lines @@
 
 RawError* Compiler::CompileOptimizedFunction(Thread* thread,
                                              const Function& function,
                                              intptr_t osr_id) {
   VMTagScope tagScope(thread, VMTag::kCompileOptimizedTagId);
   TIMELINE_FUNCTION_COMPILATION_DURATION(thread,
                                          "OptimizedFunction", function);
 
   // 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,
                                function,
                                true,  /* optimized */
                                osr_id);
 }
 
 
 // This is only used from unit tests.
@@ skipping 549 matching lines @@
 }
 
 
 void BackgroundCompiler::EnsureInit(Thread* thread) {
   UNREACHABLE();
 }
 
 #endif  // DART_PRECOMPILED_RUNTIME
 
 }  // namespace dart