[Truffle] Lazily initialised, shared string literals.

jruby · Feb 19, 2016 · 36c437e · 36c437e
1 parent 6ee231d
commit 36c437e
Showing 5 changed files with 104 additions and 1 deletion.
diff --git a/truffle/src/main/java/org/jruby/truffle/RubyContext.java b/truffle/src/main/java/org/jruby/truffle/RubyContext.java
@@ -24,6 +24,7 @@
 import org.jruby.truffle.core.objectspace.ObjectSpaceManager;
 import org.jruby.truffle.core.rope.RopeTable;
 import org.jruby.truffle.core.rubinius.RubiniusPrimitiveManager;
+import org.jruby.truffle.core.string.StringLiterals;
 import org.jruby.truffle.core.symbol.SymbolTable;
 import org.jruby.truffle.core.thread.ThreadManager;
 import org.jruby.truffle.extra.AttachmentsManager;
@@ -74,6 +75,7 @@ public class RubyContext extends ExecutionContext {
     private final AtExitManager atExitManager = new AtExitManager(this);
     private final SourceCache sourceCache = new SourceCache(new SourceLoader(this));
     private final CallStackManager callStack = new CallStackManager(this);
+    private final StringLiterals stringLiterals = new StringLiterals(this);
 
     private final CompilerOptions compilerOptions = Truffle.getRuntime().createCompilerOptions();
 
@@ -316,4 +318,8 @@ public InteropManager getInteropManager() {
     public CallStackManager getCallStack() {
         return callStack;
     }
+
+    public StringLiterals getStringLiterals() {
+        return stringLiterals;
+    }
 }
diff --git a/truffle/src/main/java/org/jruby/truffle/core/string/StringLiteral.java b/truffle/src/main/java/org/jruby/truffle/core/string/StringLiteral.java
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2016 Oracle and/or its affiliates. All rights reserved. This
+ * code is released under a tri EPL/GPL/LGPL license. You can use it,
+ * redistribute it and/or modify it under the terms of the:
+ *
+ * Eclipse Public License version 1.0
+ * GNU General Public License version 2
+ * GNU Lesser General Public License version 2.1
+ */
+package org.jruby.truffle.core.string;
+
+import com.oracle.truffle.api.CompilerDirectives;
+import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
+import com.oracle.truffle.api.object.DynamicObject;
+import org.jcodings.specific.USASCIIEncoding;
+import org.jruby.truffle.RubyContext;
+import org.jruby.truffle.core.rope.CodeRange;
+import org.jruby.truffle.core.rope.Rope;
+
+import java.nio.charset.StandardCharsets;
+
+public class StringLiteral {
+
+    private final RubyContext context;
+    private final String literal;
+
+    @CompilationFinal private volatile Rope rope;
+
+    public StringLiteral(RubyContext context, String literal) {
+        assert is7Bit(literal);
+        this.context = context;
+        this.literal = literal;
+    }
+
+    public Rope getRope() {
+        if (rope == null) {
+            CompilerDirectives.transferToInterpreterAndInvalidate();
+            rope = createRope();
+        }
+
+        return rope;
+    }
+
+    public DynamicObject getString() {
+        return StringOperations.createString(context, getRope());
+    }
+
+    private Rope createRope() {
+        // getRope is fully synchronised and returns identically the same object for the same parameters
+
+        return context.getRopeTable().getRope(
+                literal.getBytes(StandardCharsets.US_ASCII),
+                USASCIIEncoding.INSTANCE,
+                CodeRange.CR_7BIT);
+    }
+
+    private static boolean is7Bit(String literal) {
+        for (int n = 0; n < literal.length(); n++) {
+            if (literal.charAt(n) > 0b1111111) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+}
diff --git a/truffle/src/main/java/org/jruby/truffle/core/string/StringLiterals.java b/truffle/src/main/java/org/jruby/truffle/core/string/StringLiterals.java
@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2016 Oracle and/or its affiliates. All rights reserved. This
+ * code is released under a tri EPL/GPL/LGPL license. You can use it,
+ * redistribute it and/or modify it under the terms of the:
+ *
+ * Eclipse Public License version 1.0
+ * GNU General Public License version 2
+ * GNU Lesser General Public License version 2.1
+ */
+package org.jruby.truffle.core.string;
+
+import org.jruby.truffle.RubyContext;
+
+public class StringLiterals {
+
+    private final RubyContext context;
+
+    public final StringLiteral NIL;
+
+    public StringLiterals(RubyContext context) {
+        this.context = context;
+        NIL = new StringLiteral(context, "nil");
+    }
+
+}
diff --git a/truffle/src/main/java/org/jruby/truffle/language/RubyNode.java b/truffle/src/main/java/org/jruby/truffle/language/RubyNode.java
@@ -25,6 +25,7 @@
 import org.jruby.truffle.core.Layouts;
 import org.jruby.truffle.core.rope.CodeRange;
 import org.jruby.truffle.core.rope.Rope;
+import org.jruby.truffle.core.string.StringLiterals;
 import org.jruby.truffle.core.string.StringOperations;
 import org.jruby.truffle.platform.Sockets;
 import org.jruby.util.ByteList;
@@ -170,6 +171,10 @@ protected DynamicObject createString(Rope rope) {
         return StringOperations.createString(getContext(), rope);
     }
 
+    protected StringLiterals stringLiterals() {
+        return getContext().getStringLiterals();
+    }
+
     protected POSIX posix() {
         return getContext().getNativePlatform().getPosix();
     }

diff --git a/truffle/src/main/java/org/jruby/truffle/language/literal/NilNode.java b/truffle/src/main/java/org/jruby/truffle/language/literal/NilNode.java
@@ -32,7 +32,7 @@ public Object execute(VirtualFrame frame) {
 
     @Override
     public Object isDefined(VirtualFrame frame) {
-        return create7BitString("nil", UTF8Encoding.INSTANCE);
+        return stringLiterals().NIL.getString();
     }
 
 }