Instrumentation and Debugging

/**
 * Base class for implementing Truffle instruments
 */
public abstract class TruffleInstrument {
    
    /**
     * Called when instrument is created
     * @param env Instrument environment
     */
    protected abstract void onCreate(Env env);
    
    /**
     * Called when instrument is finalized
     * @param env Instrument environment
     */
    protected void onFinalize(Env env) {
        // Default implementation
    }
    
    /**
     * Called when instrument is disposed
     * @param env Instrument environment
     */
    protected void onDispose(Env env) {
        // Default implementation
    }
    
    /**
     * Instrument registration annotation
     */
    @Retention(RetentionPolicy.RUNTIME)
    @Target(ElementType.TYPE)
    public @interface Registration {
        
        /**
         * Instrument identifier
         * @return Instrument ID
         */
        String id();
        
        /**
         * Instrument name
         * @return Display name
         */
        String name();
        
        /**
         * Instrument version
         * @return Version string
         */
        String version() default "";
        
        /**
         * Whether instrument is internal
         * @return true if internal
         */
        boolean internal() default false;
        
        /**
         * Services provided by instrument
         * @return Array of service classes
         */
        Class<?>[] services() default {};
    }
    
    /**
     * Instrument environment providing access to instrumentation services
     */
    public static final class Env {
        
        /**
         * Get instrumenter for attaching listeners
         * @return Instrumenter instance
         */
        public Instrumenter getInstrumenter();
        
        /**
         * Get logger for this instrument
         * @param loggerName Logger name
         * @return TruffleLogger instance
         */
        public TruffleLogger getLogger(String loggerName);
        
        /**
         * Register service for other instruments/languages
         * @param service Service object
         */
        public void registerService(Object service);
        
        /**
         * Look up service from other instruments/languages
         * @param type Service type
         * @return Service instance or null
         */
        public <T> T lookup(Class<T> type);
        
        /**
         * Get instrument options
         * @return OptionValues instance
         */
        public OptionValues getOptions();
        
        /**
         * Get input stream for instrument
         * @return InputStream
         */
        public InputStream in();
        
        /**
         * Get output stream for instrument
         * @return OutputStream
         */
        public OutputStream out();
        
        /**
         * Get error stream for instrument
         * @return OutputStream
         */
        public OutputStream err();
    }
}

@TruffleInstrument.Registration(
    id = "myProfiler", 
    name = "My Profiler",
    version = "1.0"
)
public class MyProfiler extends TruffleInstrument {
    
    @Override
    protected void onCreate(Env env) {
        Instrumenter instrumenter = env.getInstrumenter();
        
        // Attach execution listener to all source sections
        instrumenter.attachExecutionEventListener(
            SourceSectionFilter.ANY,
            new ExecutionEventListener() {
                @Override
                public void onEnter(EventContext context, VirtualFrame frame) {
                    // Record entry time
                    recordEntry(context.getInstrumentedSourceSection());
                }
                
                @Override
                public void onReturnValue(EventContext context, VirtualFrame frame, Object result) {
                    // Record exit time and result
                    recordExit(context.getInstrumentedSourceSection(), result);
                }
            }
        );
    }
    
    private void recordEntry(SourceSection section) {
        // Profiling logic
    }
    
    private void recordExit(SourceSection section, Object result) {
        // Profiling logic
    }
}

/**
 * Main interface for attaching execution listeners and instruments
 */
public abstract class Instrumenter {
    
    /**
     * Attach execution event listener
     * @param filter Filter for source sections to instrument
     * @param listener Execution event listener
     * @return Event binding for management
     */
    public abstract EventBinding<ExecutionEventListener> attachExecutionEventListener(
        SourceSectionFilter filter, ExecutionEventListener listener);
    
    /**
     * Attach execution event factory
     * @param filter Filter for source sections to instrument
     * @param factory Factory for creating event nodes
     * @return Event binding for management
     */
    public abstract <T extends ExecutionEventNodeFactory> EventBinding<T> attachExecutionEventFactory(
        SourceSectionFilter filter, T factory);
    
    /**
     * Attach load source listener
     * @param filter Filter for sources to monitor
     * @param listener Source load listener
     * @param includeExistingSources Whether to notify for existing sources
     * @return Event binding for management
     */
    public abstract EventBinding<LoadSourceListener> attachLoadSourceListener(
        SourceFilter filter, LoadSourceListener listener, boolean includeExistingSources);
    
    /**
     * Attach load source section listener
     * @param filter Filter for source sections to monitor
     * @param listener Source section load listener
     * @param includeExistingSections Whether to notify for existing sections
     * @return Event binding for management
     */
    public abstract EventBinding<LoadSourceSectionListener> attachLoadSourceSectionListener(
        SourceSectionFilter filter, LoadSourceSectionListener listener, boolean includeExistingSections);
    
    /**
     * Get allocation reporter for memory tracking
     * @return AllocationReporter instance
     */
    public abstract AllocationReporter getAllocationReporter();
    
    /**
     * Visit loaded source sections
     * @param filter Filter for sections to visit
     * @param visitor Section visitor
     */
    public abstract void visitLoadedSourceSections(SourceSectionFilter filter, LoadSourceSectionListener visitor);
}

/**
 * Listener interface for execution events
 */
public interface ExecutionEventListener {
    
    /**
     * Called when entering instrumented node
     * @param context Event context
     * @param frame Execution frame
     */
    default void onEnter(EventContext context, VirtualFrame frame) {
        // Default implementation
    }
    
    /**
     * Called when exiting with return value
     * @param context Event context
     * @param frame Execution frame
     * @param result Return value
     */
    default void onReturnValue(EventContext context, VirtualFrame frame, Object result) {
        // Default implementation
    }
    
    /**
     * Called when exiting with exception
     * @param context Event context
     * @param frame Execution frame
     * @param exception Exception thrown
     */
    default void onReturnExceptional(EventContext context, VirtualFrame frame, Throwable exception) {
        // Default implementation
    }
}

/**
 * Factory interface for creating execution event nodes
 */
public interface ExecutionEventNodeFactory {
    
    /**
     * Create execution event node
     * @param context Event context
     * @return ExecutionEventNode instance
     */
    ExecutionEventNode create(EventContext context);
}

/**
 * Base class for execution event nodes
 */
public abstract class ExecutionEventNode extends Node {
    
    /**
     * Called when entering instrumented node
     * @param frame Execution frame
     */
    protected void onEnter(VirtualFrame frame) {
        // Default implementation
    }
    
    /**
     * Called when exiting with return value
     * @param frame Execution frame
     * @param result Return value
     */
    protected void onReturnValue(VirtualFrame frame, Object result) {
        // Default implementation
    }
    
    /**
     * Called when exiting with exception
     * @param frame Execution frame
     * @param exception Exception thrown
     */
    protected void onReturnExceptional(VirtualFrame frame, Throwable exception) {
        // Default implementation
    }
    
    /**
     * Called when node is disposed
     */
    protected void onDispose(VirtualFrame frame) {
        // Default implementation
    }
    
    /**
     * Get event context
     * @return EventContext instance
     */
    protected final EventContext getEventContext() {
        // Implementation details
        return null;
    }
}

/**
 * Context information for execution events
 */
public abstract class EventContext {
    
    /**
     * Get instrumented source section
     * @return SourceSection instance
     */
    public abstract SourceSection getInstrumentedSourceSection();
    
    /**
     * Get instrumented node
     * @return Node instance
     */
    public abstract Node getInstrumentedNode();
    
    /**
     * Check if node has tag
     * @param tag Tag class to check
     * @return true if node has tag
     */
    public abstract boolean hasTag(Class<? extends Tag> tag);
    
    /**
     * Get node object for debugging
     * @param frame Execution frame
     * @return Debug node object
     */
    public abstract Object getNodeObject(VirtualFrame frame);
    
    /**
     * Create unwind throwable for non-local control flow
     * @param info Unwind information
     * @return Unwind throwable
     */
    public abstract RuntimeException createUnwind(Object info);
    
    /**
     * Create error throwable
     * @param exception Exception to wrap
     * @return Error throwable
     */
    public abstract RuntimeException createError(RuntimeException exception);
}

/**
 * Filter for selecting source sections to instrument
 */
public final class SourceSectionFilter {
    
    /**
     * Filter matching any source section
     */
    public static final SourceSectionFilter ANY = newBuilder().build();
    
    /**
     * Create new filter builder
     * @return Builder instance
     */
    public static Builder newBuilder() {
        return new Builder();
    }
    
    /**
     * Builder for creating source section filters
     */
    public static final class Builder {
        
        /**
         * Filter by tag classes
         * @param tags Tag classes to match
         * @return Builder instance
         */
        public Builder tagIs(Class<?>... tags) {
            return this;
        }
        
        /**
         * Filter by tag classes (any match)
         * @param tags Tag classes to match
         * @return Builder instance
         */
        public Builder tagIsOneOf(Class<?>... tags) {
            return this;
        }
        
        /**
         * Filter by source sections
         * @param sections Source sections to match
         * @return Builder instance
         */
        public Builder sourceSectionEquals(SourceSection... sections) {
            return this;
        }
        
        /**
         * Filter by line range
         * @param startLine Start line (inclusive)
         * @param endLine End line (inclusive)
         * @return Builder instance
         */
        public Builder lineIn(int startLine, int endLine) {
            return this;
        }
        
        /**
         * Filter by specific line
         * @param line Line number
         * @return Builder instance
         */
        public Builder lineIs(int line) {
            return this;
        }
        
        /**
         * Filter by column range
         * @param startColumn Start column (inclusive)
         * @param endColumn End column (inclusive)
         * @return Builder instance
         */
        public Builder columnIn(int startColumn, int endColumn) {
            return this;
        }
        
        /**
         * Filter by MIME type
         * @param mimeTypes MIME types to match
         * @return Builder instance
         */
        public Builder mimeTypeIs(String... mimeTypes) {
            return this;
        }
        
        /**
         * Filter by source name pattern
         * @param namePattern Name pattern (regex)
         * @return Builder instance
         */
        public Builder sourceIs(String namePattern) {
            return this;
        }
        
        /**
         * Filter by root name pattern
         * @param namePattern Root name pattern (regex)
         * @return Builder instance
         */
        public Builder rootNameIs(String namePattern) {
            return this;
        }
        
        /**
         * Include internal sources
         * @return Builder instance
         */
        public Builder includeInternal(boolean includeInternal) {
            return this;
        }
        
        /**
         * Build the filter
         * @return SourceSectionFilter instance
         */
        public SourceSectionFilter build() {
            return new SourceSectionFilter();
        }
    }
}

/**
 * Filter for selecting sources to monitor
 */
public final class SourceFilter {
    
    /**
     * Filter matching any source
     */
    public static final SourceFilter ANY = newBuilder().build();
    
    /**
     * Create new filter builder
     * @return Builder instance
     */
    public static Builder newBuilder() {
        return new Builder();
    }
    
    /**
     * Builder for creating source filters
     */
    public static final class Builder {
        
        /**
         * Filter by MIME type
         * @param mimeTypes MIME types to match
         * @return Builder instance
         */
        public Builder mimeTypeIs(String... mimeTypes) {
            return this;
        }
        
        /**
         * Filter by source name pattern
         * @param namePattern Name pattern (regex)
         * @return Builder instance
         */
        public Builder sourceIs(String namePattern) {
            return this;
        }
        
        /**
         * Include internal sources
         * @return Builder instance
         */
        public Builder includeInternal(boolean includeInternal) {
            return this;
        }
        
        /**
         * Build the filter
         * @return SourceFilter instance
         */
        public SourceFilter build() {
            return new SourceFilter();
        }
    }
}

/**
 * Reports memory allocations to registered listeners
 */
public abstract class AllocationReporter {
    
    /**
     * Add allocation listener
     * @param listener Allocation listener
     */
    public abstract void addListener(AllocationListener listener);
    
    /**
     * Remove allocation listener
     * @param listener Allocation listener
     */
    public abstract void removeListener(AllocationListener listener);
    
    /**
     * Report object allocation
     * @param newObject Newly allocated object
     */
    public abstract void onEnter(Object newObject);
    
    /**
     * Report allocation with size
     * @param newObject Newly allocated object
     * @param size Allocation size in bytes
     */
    public abstract void onEnter(Object newObject, long size);
    
    /**
     * Report allocation with language and size
     * @param newObject Newly allocated object
     * @param size Allocation size in bytes
     * @param language Allocating language
     */
    public abstract void onEnter(Object newObject, long size, TruffleLanguage<?> language);
}

/**
 * Listener interface for allocation events
 */
public interface AllocationListener {
    
    /**
     * Called when object is allocated
     * @param event Allocation event
     */
    void onAllocation(AllocationEvent event);
}

/**
 * Event representing an object allocation
 */
public abstract class AllocationEvent {
    
    /**
     * Get allocated object
     * @return Allocated object
     */
    public abstract Object getAllocatedObject();
    
    /**
     * Get allocation size
     * @return Size in bytes
     */
    public abstract long getSize();
    
    /**
     * Get allocating language
     * @return TruffleLanguage instance
     */
    public abstract TruffleLanguage<?> getLanguage();
    
    /**
     * Get allocation stack trace
     * @return Array of stack trace elements
     */
    public abstract StackTraceElement[] getStackTrace();
}

/**
 * Represents a binding between instrument and instrumented code
 * @param <T> Bound element type
 */
public abstract class EventBinding<T> {
    
    /**
     * Check if binding is disposed
     * @return true if disposed
     */
    public abstract boolean isDisposed();
    
    /**
     * Dispose this binding
     */
    public abstract void dispose();
    
    /**
     * Get bound element
     * @return Bound element
     */
    public abstract T getElement();
    
    /**
     * Check if binding is attached to specific instrumented node
     * @param node Node to check
     * @return true if attached
     */
    public abstract boolean isAttached(Node node);
}

/**
 * Base class for node tags
 */
public abstract class Tag {
    // Base tag class
}

/**
 * Standard tags for common language constructs
 */
public final class StandardTags {
    
    /**
     * Tag for expression nodes
     */
    public static final class ExpressionTag extends Tag {
        private ExpressionTag() {}
    }
    
    /**
     * Tag for statement nodes
     */
    public static final class StatementTag extends Tag {
        private StatementTag() {}
    }
    
    /**
     * Tag for function call nodes
     */
    public static final class CallTag extends Tag {
        private CallTag() {}
    }
    
    /**
     * Tag for root nodes
     */
    public static final class RootTag extends Tag {
        private RootTag() {}
    }
    
    /**
     * Tag for root body nodes
     */
    public static final class RootBodyTag extends Tag {
        private RootBodyTag() {}
    }
    
    /**
     * Tag for read variable nodes
     */
    public static final class ReadVariableTag extends Tag {
        private ReadVariableTag() {}
    }
    
    /**
     * Tag for write variable nodes
     */
    public static final class WriteVariableTag extends Tag {
        private WriteVariableTag() {}
    }
}

/**
 * Marks nodes as instrumentable
 */
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
public @interface Instrumentable {
    
    /**
     * Factory class for creating wrappers
     * @return Wrapper factory class
     */
    Class<? extends ProvidedTags> factory();
}

/**
 * Tags provided by an instrumentable node
 */
public abstract class ProvidedTags {
    
    /**
     * Get provided tag classes
     * @return Array of tag classes
     */
    public abstract Class<?>[] getProvidedTags();
}

/**
 * Generates wrapper nodes for instrumentation
 */
@Retention(RetentionPolicy.CLASS)
@Target(ElementType.TYPE)
public @interface GenerateWrapper {
    
    /**
     * Delegate factory class
     * @return Factory class
     */
    Class<?> delegateTo();
}

/**
 * Listener interface for source loading events
 */
public interface LoadSourceListener {
    
    /**
     * Called when source is loaded
     * @param event Source load event
     */
    void onLoad(LoadSourceEvent event);
}

/**
 * Listener interface for source section loading events
 */
public interface LoadSourceSectionListener {
    
    /**
     * Called when source section is loaded
     * @param event Source section load event
     */
    void onLoad(LoadSourceSectionEvent event);
}

/**
 * Event representing source loading
 */
public abstract class LoadSourceEvent {
    
    /**
     * Get loaded source
     * @return Source instance
     */
    public abstract Source getSource();
}

/**
 * Event representing source section loading
 */
public abstract class LoadSourceSectionEvent {
    
    /**
     * Get loaded source section
     * @return SourceSection instance
     */
    public abstract SourceSection getSourceSection();
    
    /**
     * Get associated node
     * @return Node instance
     */
    public abstract Node getNode();
}

/**
 * Options for instrumentation configuration
 */
public final class OptionValues {
    
    /**
     * Get option value
     * @param key Option key
     * @return Option value
     */
    public <T> T get(OptionKey<T> key) {
        return null;
    }
    
    /**
     * Check if option has value
     * @param key Option key
     * @return true if has value
     */
    public boolean hasBeenSet(OptionKey<?> key) {
        return false;
    }
}

/**
 * Key for accessing option values
 * @param <T> Option value type
 */
public final class OptionKey<T> {
    
    /**
     * Get default value
     * @return Default value
     */
    public T getDefaultValue() {
        return null;
    }
}

/**
 * Descriptor for option definitions
 */
public final class OptionDescriptor {
    
    /**
     * Get option name
     * @return Option name
     */
    public String getName() {
        return null;
    }
    
    /**
     * Get option help text
     * @return Help text
     */
    public String getHelp() {
        return null;
    }
    
    /**
     * Get option key
     * @return OptionKey instance
     */
    public OptionKey<?> getKey() {
        return null;
    }
}