initial version of builtin that dumps function ASTs to IGV before and after calling

com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/builtin/fastr/FastRRunDump.java

+package com.oracle.truffle.r.nodes.builtin.fastr;
+
+import static com.oracle.truffle.r.runtime.RBuiltinKind.*;
+
+import com.oracle.graal.debug.*;
+import com.oracle.graal.debug.Debug.Scope;
+import com.oracle.truffle.api.*;
+import com.oracle.truffle.api.dsl.*;
+import com.oracle.truffle.api.frame.*;
+import com.oracle.truffle.api.nodes.*;
+import com.oracle.truffle.r.nodes.*;
+import com.oracle.truffle.r.nodes.access.*;
+import com.oracle.truffle.r.nodes.builtin.*;
+import com.oracle.truffle.r.runtime.*;
+import com.oracle.truffle.r.runtime.data.*;
+
+/**
+ * Run a FastR function, and dump its AST to IGV before and after running. If no function is passed,
+ * this builtin does not do anything.
+ */
+@RBuiltin(name = "fastr.rundump", parameterNames = {"function"}, kind = PRIMITIVE)
+public abstract class FastRRunDump extends RInvisibleBuiltinNode {
+
+    // TODO Make this more versatile by allowing actual function calls with arguments to be
+    // observed. This requires ... to work properly.
+
+    @Child private IndirectCallNode call = Truffle.getRuntime().createIndirectCallNode();
+
+    private final GraphPrintVisitor graphPrinter = new GraphPrintVisitor();
+
+    @Override
+    public RNode[] getParameterValues() {
+        return new RNode[]{ConstantNode.create(RNull.instance)};
+    }
+
+    @Specialization
+    public Object runDump(RNull function) {
+        return function;
+    }
+
+    @Specialization
+    public Object runDump(VirtualFrame frame, RFunction function) {
+        controlVisibility();
+        Object r = RNull.instance;
+        graphPrinter.beginGroup(RRuntime.toString(function));
+        try (Scope s = Debug.scope("FastR")) {
+            graphPrinter.beginGraph("before").visit(function.getTarget().getRootNode());
+            r = call.call(frame, function.getTarget(), RArguments.create(function));
+            graphPrinter.beginGraph("after").visit(function.getTarget().getRootNode());
+        } catch (Throwable t) {
+            Debug.handle(t);
+        } finally {
+            graphPrinter.printToNetwork(true);
+        }
+        return r;
+    }
+
+}