Make compiler more acceptive wrt Isolate::use_crankshaft.

This allows using %OptimizeFunctionOnNextCall and friends even when
Crankshaft is disabled. Note that this should only affect code paths
that are not relevant to performance. By now we have a single bailout
point in place within OptimizedCompileJob::CreateGraph that ensures
Crankshaft is only used when enabled and supported.

R=titzer@chromium.org

Review URL: https://codereview.chromium.org/999173007

Cr-Commit-Position: refs/heads/master@{#27367}

src/factory.cc

@@ -1353,8 +1353,8 @@ Handle<JSObject> Factory::NewFunctionPrototype(Handle<JSFunction> function) {
 
 static bool ShouldOptimizeNewClosure(Isolate* isolate,
                                      Handle<SharedFunctionInfo> info) {
-  return isolate->use_crankshaft() && !info->is_toplevel() &&
-         info->is_compiled() && info->allows_lazy_compilation();
+  return !info->is_toplevel() && info->is_compiled() &&
+         info->allows_lazy_compilation();
 }
 
 

src/objects.cc

@@ -9626,7 +9626,6 @@ void JSFunction::JSFunctionIterateBody(int object_size, ObjectVisitor* v) {
 
 void JSFunction::MarkForOptimization() {
   Isolate* isolate = GetIsolate();
-  DCHECK(isolate->use_crankshaft());
   DCHECK(!IsOptimized());
   DCHECK(shared()->allows_lazy_compilation() || code()->optimizable());
   set_code_no_write_barrier(
@@ -9650,7 +9649,6 @@ void JSFunction::AttemptConcurrentOptimization() {
     // recompilation race.  This goes away as soon as OSR becomes one-shot.
     return;
   }
-  DCHECK(isolate->use_crankshaft());
   DCHECK(!IsInOptimizationQueue());
   DCHECK(is_compiled() || isolate->debug()->has_break_points());
   DCHECK(!IsOptimized());

src/runtime/runtime-compiler.cc

@@ -47,7 +47,6 @@ RUNTIME_FUNCTION(Runtime_CompileOptimized) {
   DCHECK(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSFunction, function, 0);
   CONVERT_BOOLEAN_ARG_CHECKED(concurrent, 1);
-  DCHECK(isolate->use_crankshaft());
 
   Compiler::ConcurrencyMode mode =
       concurrent ? Compiler::CONCURRENT : Compiler::NOT_CONCURRENT;

src/runtime/runtime-test.cc

@@ -89,8 +89,6 @@ RUNTIME_FUNCTION(Runtime_OptimizeFunctionOnNextCall) {
                  (function->code()->kind() == Code::FUNCTION &&
                   function->code()->optimizable()));
 
-  if (!isolate->use_crankshaft()) return isolate->heap()->undefined_value();
-
   // If the function is already optimized, just return.
   if (function->IsOptimized()) return isolate->heap()->undefined_value();
 
@@ -136,8 +134,6 @@ RUNTIME_FUNCTION(Runtime_OptimizeOsr) {
                  (function->code()->kind() == Code::FUNCTION &&
                   function->code()->optimizable()));
 
-  if (!isolate->use_crankshaft()) return isolate->heap()->undefined_value();
-
   // If the function is already optimized, just return.
   if (function->IsOptimized()) return isolate->heap()->undefined_value();