public static void Init(IScriptable scope, bool zealed)
{
Continuation obj = new Continuation();
obj.ExportAsJSClass(MAX_PROTOTYPE_ID, scope, zealed);
}
static void captureContinuation (Context cx, CallFrame frame, int stackTop)
{
Continuation c = new Continuation ();
ScriptRuntime.setObjectProtoAndParent (c, ScriptRuntime.getTopCallScope (cx));
// Make sure that all frames upstack frames are frozen
CallFrame x = frame.parentFrame;
while (x != null && !x.frozen) {
x.frozen = true;
// Allow to GC unused stack space
for (int i = x.savedStackTop + 1; i != x.stack.Length; ++i) {
// Allow to GC unused stack space
x.stack [i] = null;
}
if (x.savedCallOp == Token.CALL) {
// the call will always overwrite the stack top with the result
x.stack [x.savedStackTop] = null;
}
else {
if (x.savedCallOp != Token.NEW)
Context.CodeBug ();
// the new operator uses stack top to store the constructed
// object so it shall not be cleared: see comments in
// setCallResult
}
x = x.parentFrame;
}
c.initImplementation (frame.parentFrame);
frame.stack [stackTop] = c;
}
internal ContinuationJump (Continuation c, CallFrame current)
{
this.capturedFrame = (CallFrame)c.Implementation;
if (this.capturedFrame == null || current == null) {
// Continuation and current execution does not share
// any frames if there is nothing to capture or
// if there is no currently executed frames
this.branchFrame = null;
}
else {
// Search for branch frame where parent frame chains starting
// from captured and current meet.
CallFrame chain1 = this.capturedFrame;
CallFrame chain2 = current;
// First work parents of chain1 or chain2 until the same
// frame depth.
int diff = chain1.frameIndex - chain2.frameIndex;
if (diff != 0) {
if (diff < 0) {
// swap to make sure that
// chain1.frameIndex > chain2.frameIndex and diff > 0
chain1 = current;
chain2 = this.capturedFrame;
diff = -diff;
}
do {
chain1 = chain1.parentFrame;
}
while (--diff != 0);
if (chain1.frameIndex != chain2.frameIndex)
Context.CodeBug ();
}
// Now walk parents in parallel until a shared frame is found
// or until the root is reached.
while (chain1 != chain2 && chain1 != null) {
chain1 = chain1.parentFrame;
chain2 = chain2.parentFrame;
}
this.branchFrame = chain1;
if (this.branchFrame != null && !this.branchFrame.frozen)
Context.CodeBug ();
}
}
public static object restartContinuation (Continuation c, Context cx, IScriptable scope, object [] args)
{
if (!ScriptRuntime.hasTopCall (cx)) {
return ScriptRuntime.DoTopCall (c, cx, scope, null, args);
}
object arg;
if (args.Length == 0) {
arg = Undefined.Value;
}
else {
arg = args [0];
}
CallFrame capturedFrame = (CallFrame)c.Implementation;
if (capturedFrame == null) {
// No frames to restart
return arg;
}
ContinuationJump cjump = new ContinuationJump (c, null);
cjump.result = arg;
return InterpretLoop (cx, null, cjump);
}
public static void Init (IScriptable scope, bool zealed)
{
Continuation obj = new Continuation ();
obj.ExportAsJSClass (MAX_PROTOTYPE_ID, scope, zealed);
}
