Avoid creating an Engine during RubyLauncher.preprocessArguments()

PullRequest: truffleruby/522

Author: eregon

spec/tags/truffle/launcher_tags.txt

@@ -62,3 +62,4 @@ slow:The launcher does not create context on --version and -v
 aot(no sulong):The launcher 'gem' in `RbConfig::CONFIG['bindir']` directory runs when symlinked
 aot(no sulong):The launcher 'gem' in `RbConfig::CONFIG['extra_bindirs'][0]` directory runs when symlinked
 aot(no sulong):The launcher 'gem' in `RbConfig::CONFIG['extra_bindirs'][1]` directory runs when symlinked
+slow:The launcher applies Truffle options

spec/truffle/launcher_spec.rb

@@ -280,4 +280,15 @@ def should_print_full_java_command(options, env: {})
     out.should include(':b')
   end
 
+  guard -> { TruffleRuby.graal? } do
+    it "applies Truffle options" do
+      prefix = TruffleRuby.native? ? '--native.' : '--jvm.'
+      options = [
+        "#{prefix}Dgraal.TraceTruffleCompilation=true",
+        "#{prefix}Dgraal.TruffleBackgroundCompilation=false",
+      ].join(" ")
+      out = ruby_exe("2000.times {}", options: options, args: "2>&1")
+      out.should include("[truffle] opt done")
+    end
+  end
 end

src/launcher/java/org/truffleruby/launcher/RubyLauncher.java

@@ -13,7 +13,6 @@
 import org.graalvm.nativeimage.ProcessProperties;
 import org.graalvm.options.OptionCategory;
 import org.graalvm.polyglot.Context;
-import org.graalvm.polyglot.Engine;
 import org.graalvm.polyglot.PolyglotException;
 import org.graalvm.polyglot.Source;
 import org.truffleruby.launcher.options.CommandLineException;
@@ -44,12 +43,6 @@ public static void main(String[] args) {
         new RubyLauncher().launch(args);
     }
 
-    static boolean isSulongAvailable() {
-        try (Engine engine = Engine.create()) {
-            return engine.getLanguages().containsKey(TruffleRuby.LLVM_ID);
-        }
-    }
-
     @Override
     protected String getLanguageId() {
         return TruffleRuby.LANGUAGE_ID;
@@ -121,7 +114,7 @@ protected List<String> preprocessArguments(List<String> args, Map<String, String
                 }
 
                 // In a native standalone distribution outside of GraalVM, we need to give the path to libsulong
-                if (!isGraalVMAvailable() && isSulongAvailable()) {
+                if (!isGraalVMAvailable()) { // TODO (eregon, 9 Jan 2019): This should check if Sulong is available.
                     final String rubyHome = new File(launcher).getParentFile().getParent();
                     final String libSulongPath = rubyHome + "/lib/cext/sulong-libs";