--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.jvmci.options.processor/src/com/oracle/jvmci/options/processor/OptionProcessor.java	Tue May 26 23:21:15 2015 +0200
@@ -0,0 +1,331 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.jvmci.options.processor;
+
+import java.io.*;
+import java.util.*;
+
+import javax.annotation.processing.*;
+import javax.lang.model.*;
+import javax.lang.model.element.*;
+import javax.lang.model.type.*;
+import javax.lang.model.util.*;
+import javax.tools.Diagnostic.Kind;
+import javax.tools.*;
+
+import com.oracle.jvmci.options.*;
+
+
+/**
+ * Processes static fields annotated with {@link Option}. An {@link Options} service is generated
+ * for each top level class containing at least one such field. These service objects can be
+ * retrieved as follows:
+ *
+ * <pre>
+ * ServiceLoader&lt;Options&gt; sl = ServiceLoader.load(Options.class);
+ * for (Options opts : sl) {
+ *     for (OptionDescriptor desc : sl) {
+ *         // use desc
+ *     }
+ * }
+ * </pre>
+ */
+@SupportedAnnotationTypes({"com.oracle.jvmci.options.Option"})
+public class OptionProcessor extends AbstractProcessor {
+
+    @Override
+    public SourceVersion getSupportedSourceVersion() {
+        return SourceVersion.latest();
+    }
+
+    private final Set<Element> processed = new HashSet<>();
+
+    private void processElement(Element element, OptionsInfo info) {
+
+        if (!element.getModifiers().contains(Modifier.STATIC)) {
+            processingEnv.getMessager().printMessage(Kind.ERROR, "Option field must be static", element);
+            return;
+        }
+
+        Option annotation = element.getAnnotation(Option.class);
+        assert annotation != null;
+        assert element instanceof VariableElement;
+        assert element.getKind() == ElementKind.FIELD;
+        VariableElement field = (VariableElement) element;
+        String fieldName = field.getSimpleName().toString();
+
+        Elements elements = processingEnv.getElementUtils();
+        Types types = processingEnv.getTypeUtils();
+
+        TypeMirror fieldType = field.asType();
+        if (fieldType.getKind() != TypeKind.DECLARED) {
+            processingEnv.getMessager().printMessage(Kind.ERROR, "Option field must be of type " + OptionValue.class.getName(), element);
+            return;
+        }
+        DeclaredType declaredFieldType = (DeclaredType) fieldType;
+
+        TypeMirror optionValueType = elements.getTypeElement(OptionValue.class.getName()).asType();
+        if (!types.isSubtype(fieldType, types.erasure(optionValueType))) {
+            String msg = String.format("Option field type %s is not a subclass of %s", fieldType, optionValueType);
+            processingEnv.getMessager().printMessage(Kind.ERROR, msg, element);
+            return;
+        }
+
+        if (!field.getModifiers().contains(Modifier.STATIC)) {
+            processingEnv.getMessager().printMessage(Kind.ERROR, "Option field must be static", element);
+            return;
+        }
+
+        String help = annotation.help();
+        if (help.length() != 0) {
+            char firstChar = help.charAt(0);
+            if (!Character.isUpperCase(firstChar)) {
+                processingEnv.getMessager().printMessage(Kind.ERROR, "Option help text must start with upper case letter", element);
+                return;
+            }
+        }
+
+        String optionName = annotation.name();
+        if (optionName.equals("")) {
+            optionName = fieldName;
+        }
+
+        DeclaredType declaredOptionValueType = declaredFieldType;
+        while (!types.isSameType(types.erasure(declaredOptionValueType), types.erasure(optionValueType))) {
+            List<? extends TypeMirror> directSupertypes = types.directSupertypes(declaredFieldType);
+            assert !directSupertypes.isEmpty();
+            declaredOptionValueType = (DeclaredType) directSupertypes.get(0);
+        }
+
+        assert !declaredOptionValueType.getTypeArguments().isEmpty();
+        String optionType = declaredOptionValueType.getTypeArguments().get(0).toString();
+        if (optionType.startsWith("java.lang.")) {
+            optionType = optionType.substring("java.lang.".length());
+        }
+
+        Element enclosing = element.getEnclosingElement();
+        String declaringClass = "";
+        String separator = "";
+        Set<Element> originatingElementsList = info.originatingElements;
+        originatingElementsList.add(field);
+        while (enclosing != null) {
+            if (enclosing.getKind() == ElementKind.CLASS || enclosing.getKind() == ElementKind.INTERFACE) {
+                if (enclosing.getModifiers().contains(Modifier.PRIVATE)) {
+                    String msg = String.format("Option field cannot be declared in a private %s %s", enclosing.getKind().name().toLowerCase(), enclosing);
+                    processingEnv.getMessager().printMessage(Kind.ERROR, msg, element);
+                    return;
+                }
+                originatingElementsList.add(enclosing);
+                declaringClass = enclosing.getSimpleName() + separator + declaringClass;
+                separator = ".";
+            } else {
+                assert enclosing.getKind() == ElementKind.PACKAGE;
+            }
+            enclosing = enclosing.getEnclosingElement();
+        }
+
+        info.options.add(new OptionInfo(optionName, help, optionType, declaringClass, field));
+    }
+
+    private void createFiles(OptionsInfo info) {
+        String pkg = ((PackageElement) info.topDeclaringType.getEnclosingElement()).getQualifiedName().toString();
+        Name topDeclaringClass = info.topDeclaringType.getSimpleName();
+
+        String optionsClassName = topDeclaringClass + "_" + Options.class.getSimpleName();
+        Element[] originatingElements = info.originatingElements.toArray(new Element[info.originatingElements.size()]);
+
+        Filer filer = processingEnv.getFiler();
+        try (PrintWriter out = createSourceFile(pkg, optionsClassName, filer, originatingElements)) {
+
+            out.println("// CheckStyle: stop header check");
+            out.println("// GENERATED CONTENT - DO NOT EDIT");
+            out.println("// Source: " + topDeclaringClass + ".java");
+            out.println("package " + pkg + ";");
+            out.println("");
+            out.println("import java.util.*;");
+            out.println("import " + Options.class.getPackage().getName() + ".*;");
+            out.println("");
+            out.println("public class " + optionsClassName + " implements " + Options.class.getSimpleName() + " {");
+            out.println("    @Override");
+            String desc = OptionDescriptor.class.getSimpleName();
+            out.println("    public Iterator<" + desc + "> iterator() {");
+            out.println("        // CheckStyle: stop line length check");
+            out.println("        List<" + desc + "> options = Arrays.asList(");
+
+            boolean needPrivateFieldAccessor = false;
+            int i = 0;
+            Collections.sort(info.options);
+            for (OptionInfo option : info.options) {
+                String optionValue;
+                if (option.field.getModifiers().contains(Modifier.PRIVATE)) {
+                    needPrivateFieldAccessor = true;
+                    optionValue = "field(" + option.declaringClass + ".class, \"" + option.field.getSimpleName() + "\")";
+                } else {
+                    optionValue = option.declaringClass + "." + option.field.getSimpleName();
+                }
+                String name = option.name;
+                String type = option.type;
+                String help = option.help;
+                String declaringClass = option.declaringClass;
+                Name fieldName = option.field.getSimpleName();
+                String comma = i == info.options.size() - 1 ? "" : ",";
+                out.printf("            new %s(\"%s\", %s.class, \"%s\", %s.class, \"%s\", %s)%s\n", desc, name, type, help, declaringClass, fieldName, optionValue, comma);
+                i++;
+            }
+            out.println("        );");
+            out.println("        // CheckStyle: resume line length check");
+            out.println("        return options.iterator();");
+            out.println("    }");
+            if (needPrivateFieldAccessor) {
+                out.println("    private static " + OptionValue.class.getSimpleName() + "<?> field(Class<?> declaringClass, String fieldName) {");
+                out.println("        try {");
+                out.println("            java.lang.reflect.Field field = declaringClass.getDeclaredField(fieldName);");
+                out.println("            field.setAccessible(true);");
+                out.println("            return (" + OptionValue.class.getSimpleName() + "<?>) field.get(null);");
+                out.println("        } catch (Exception e) {");
+                out.println("            throw (InternalError) new InternalError().initCause(e);");
+                out.println("        }");
+                out.println("    }");
+            }
+            out.println("}");
+        }
+
+        try {
+            createProviderFile(pkg, optionsClassName, originatingElements);
+        } catch (IOException e) {
+            processingEnv.getMessager().printMessage(Kind.ERROR, e.getMessage(), info.topDeclaringType);
+        }
+    }
+
+    private void createProviderFile(String pkg, String providerClassName, Element... originatingElements) throws IOException {
+        String filename = "META-INF/providers/" + pkg + "." + providerClassName;
+        FileObject file = processingEnv.getFiler().createResource(StandardLocation.CLASS_OUTPUT, "", filename, originatingElements);
+        PrintWriter writer = new PrintWriter(new OutputStreamWriter(file.openOutputStream(), "UTF-8"));
+        writer.println(Options.class.getName());
+        writer.close();
+    }
+
+    protected PrintWriter createSourceFile(String pkg, String relativeName, Filer filer, Element... originatingElements) {
+        try {
+            // Ensure Unix line endings to comply with Graal code style guide checked by Checkstyle
+            JavaFileObject sourceFile = filer.createSourceFile(pkg + "." + relativeName, originatingElements);
+            return new PrintWriter(sourceFile.openWriter()) {
+
+                @Override
+                public void println() {
+                    print("\n");
+                }
+            };
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    static class OptionInfo implements Comparable<OptionInfo> {
+
+        final String name;
+        final String help;
+        final String type;
+        final String declaringClass;
+        final VariableElement field;
+
+        public OptionInfo(String name, String help, String type, String declaringClass, VariableElement field) {
+            this.name = name;
+            this.help = help;
+            this.type = type;
+            this.declaringClass = declaringClass;
+            this.field = field;
+        }
+
+        @Override
+        public int compareTo(OptionInfo other) {
+            return name.compareTo(other.name);
+        }
+
+        @Override
+        public String toString() {
+            return declaringClass + "." + field;
+        }
+    }
+
+    static class OptionsInfo {
+
+        final Element topDeclaringType;
+        final List<OptionInfo> options = new ArrayList<>();
+        final Set<Element> originatingElements = new HashSet<>();
+
+        public OptionsInfo(Element topDeclaringType) {
+            this.topDeclaringType = topDeclaringType;
+        }
+    }
+
+    private static Element topDeclaringType(Element element) {
+        Element enclosing = element.getEnclosingElement();
+        if (enclosing == null || enclosing.getKind() == ElementKind.PACKAGE) {
+            assert element.getKind() == ElementKind.CLASS || element.getKind() == ElementKind.INTERFACE;
+            return element;
+        }
+        return topDeclaringType(enclosing);
+    }
+
+    @Override
+    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
+        if (roundEnv.processingOver()) {
+            return true;
+        }
+
+        Map<Element, OptionsInfo> map = new HashMap<>();
+        for (Element element : roundEnv.getElementsAnnotatedWith(Option.class)) {
+            if (!processed.contains(element)) {
+                processed.add(element);
+                Element topDeclaringType = topDeclaringType(element);
+                OptionsInfo options = map.get(topDeclaringType);
+                if (options == null) {
+                    options = new OptionsInfo(topDeclaringType);
+                    map.put(topDeclaringType, options);
+                }
+                processElement(element, options);
+            }
+        }
+
+        boolean ok = true;
+        Map<String, OptionInfo> uniqueness = new HashMap<>();
+        for (OptionsInfo info : map.values()) {
+            for (OptionInfo option : info.options) {
+                OptionInfo conflict = uniqueness.put(option.name, option);
+                if (conflict != null) {
+                    processingEnv.getMessager().printMessage(Kind.ERROR, "Duplicate option names for " + option + " and " + conflict, option.field);
+                    ok = false;
+                }
+            }
+        }
+
+        if (ok) {
+            for (OptionsInfo info : map.values()) {
+                createFiles(info);
+            }
+        }
+
+        return true;
+    }
+}