6model bits for representing continuations as objects, also s/shift/c…

…ontrol/ (oops)

docs/continuations.pod

@@ -48,8 +48,8 @@ B<Details here are subject greatly to change.>
 
     # should be 3 * 3 * 10 = 90
     # will infinite loop if the clones are removed
-    my $cont := nqp::continuationreset(-> $ {
-        3 * (nqp::continuationshift(0, -> $k { $k }))();
+    my $cont := nqp::continuationreset(nqp::null(), {
+        3 * (nqp::continuationshift(nqp::null(), -> $k { $k }))();
     });
     nqp::continuationinvoke(nqp::continuationclone($cont),
         -> { nqp::continuationinvoke(nqp::continuationclone($cont)), -> { 10 }) });

src/vm/jvm/QAST/Compiler.nqp

@@ -2403,8 +2403,8 @@ sub contop($name, @params) {
 }
 QAST::OperationsJAST.map_classlib_core_op('continuationclone', $TYPE_OPS, 'continuationclone', [$RT_OBJ], $RT_OBJ, :tc);
 contop('continuationreset', [$RT_OBJ, $RT_OBJ]);
-contop('continuationshift', [$RT_OBJ, $RT_OBJ]);
-contop('continuationinvoke', [$RT_OBJ]);
+contop('continuationcontrol', [$RT_INT, $RT_OBJ, $RT_OBJ]);
+contop('continuationinvoke', [$RT_OBJ, $RT_OBJ]);
 
 
 class QAST::CompilerJAST {

src/vm/jvm/runtime/org/perl6/nqp/runtime/GlobalContext.java

@@ -60,6 +60,11 @@ public class GlobalContext {
      */
     public SixModelObject SCRef;
 
+    /**
+     * Continuation type; a basic, method-less type with the Continuation REPR.
+     */
+    public SixModelObject Continuation;
+
     /**
      * ContextRef type; a basic, method-less type with the ContextRef REPR.
      */

src/vm/jvm/runtime/org/perl6/nqp/runtime/Ops.java

@@ -4148,10 +4148,10 @@ public static SixModelObject continuationclone(SixModelObject in, ThreadContext
     public static SixModelObject continuationreset(SixModelObject key, SixModelObject run, ThreadContext tc, ResumeStatus.Frame resume) {
         throw new UnsupportedOperationException();
     }
-    public static SixModelObject continuationshift(SixModelObject key, SixModelObject run, ThreadContext tc, ResumeStatus.Frame resume) {
+    public static SixModelObject continuationcontrol(long protect, SixModelObject key, SixModelObject run, ThreadContext tc, ResumeStatus.Frame resume) {
         throw new UnsupportedOperationException();
     }
-    public static SixModelObject continuationinvoke(SixModelObject cont, ThreadContext tc, ResumeStatus.Frame resume) {
+    public static SixModelObject continuationinvoke(SixModelObject cont, SixModelObject arg, ThreadContext tc, ResumeStatus.Frame resume) {
         throw new UnsupportedOperationException();
     }
 }

src/vm/jvm/runtime/org/perl6/nqp/runtime/ResumeStatus.java

@@ -1,11 +1,12 @@
 package org.perl6.nqp.runtime;
 
 import java.lang.invoke.MethodHandle;
+import org.perl6.nqp.sixmodel.SixModelObject;
 
 /**
  * Represents a composable continuation.
  */
-public class ResumeStatus {
+public class ResumeStatus extends SixModelObject {
     /**
      * Represents one saved, not-currently-executing execution frame.
      */
@@ -48,9 +49,4 @@ public void resumeNext() throws Throwable {
 
     /** The first frame of this continuation.  Subsequent frames can be accessed using {@link Frame#next}. */
     public Frame top;
-
-    /** Builds a new continuation from the stack stored in a {@link SaveStackException}. */
-    public ResumeStatus(SaveStackException ex) {
-        this.top = ex.top;
-    }
 }

src/vm/jvm/runtime/org/perl6/nqp/sixmodel/KnowHOWBootstrapper.java

@@ -39,6 +39,8 @@ public static void bootstrap(ThreadContext tc)
         tc.gc.BOOTStrArray = bootTypedArray(tc, "BOOTStrArray", tc.gc.BOOTStr);
 
         tc.gc.MultiCache = bootType(tc, "MultiCache", "MultiCache");
+
+        tc.gc.Continuation = bootType(tc, "Continuation", "Continuation");
 
         Ops.setboolspec(tc.gc.BOOTIter, BoolificationSpec.MODE_ITER, null, tc);
         Ops.setboolspec(tc.gc.BOOTInt, BoolificationSpec.MODE_UNBOX_INT, null, tc);

src/vm/jvm/runtime/org/perl6/nqp/sixmodel/REPRRegistry.java

@@ -6,6 +6,7 @@
 import org.perl6.nqp.sixmodel.reprs.CallCapture;
 import org.perl6.nqp.sixmodel.reprs.CodeRefREPR;
 import org.perl6.nqp.sixmodel.reprs.ContextRef;
+import org.perl6.nqp.sixmodel.reprs.Continuation;
 import org.perl6.nqp.sixmodel.reprs.IOHandle;
 import org.perl6.nqp.sixmodel.reprs.KnowHOWAttribute;
 import org.perl6.nqp.sixmodel.reprs.KnowHOWREPR;
@@ -61,6 +62,7 @@ public static void setup() {
         addREPR("Uninstantiable", new Uninstantiable());
         addREPR("SCRef", new SCRef());
         addREPR("ContextRef", new ContextRef());
+        addREPR("Continuation", new Continuation());
         addREPR("CodeRef", new CodeRefREPR());
         addREPR("CallCapture", new CallCapture());
         addREPR("NFA", new NFA());

src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/Continuation.java

@@ -0,0 +1,35 @@
+package org.perl6.nqp.sixmodel.reprs;
+
+import org.perl6.nqp.runtime.ExceptionHandling;
+import org.perl6.nqp.runtime.ResumeStatus;
+import org.perl6.nqp.runtime.ThreadContext;
+import org.perl6.nqp.sixmodel.REPR;
+import org.perl6.nqp.sixmodel.STable;
+import org.perl6.nqp.sixmodel.SerializationReader;
+import org.perl6.nqp.sixmodel.SixModelObject;
+import org.perl6.nqp.sixmodel.TypeObject;
+
+public class Continuation extends REPR {
+    public SixModelObject type_object_for(ThreadContext tc, SixModelObject HOW) {
+        STable st = new STable(this, HOW);
+        SixModelObject obj = new TypeObject();
+        obj.st = st;
+        st.WHAT = obj;
+        return st.WHAT;
+    }
+
+    public SixModelObject allocate(ThreadContext tc, STable st) {
+        ResumeStatus obj = new ResumeStatus();
+        obj.st = st;
+        return obj;
+    }
+
+    public SixModelObject deserialize_stub(ThreadContext tc, STable st) {
+        throw ExceptionHandling.dieInternal(tc, "Continuation does not participate in serialization");
+    }
+
+    public void deserialize_finish(ThreadContext tc, STable st,
+            SerializationReader reader, SixModelObject obj) {
+        throw ExceptionHandling.dieInternal(tc, "Continuation does not participate in serialization");
+    }
+}