private Select VisitSelect(Select select)
{
JoinStatementList newJoinStatementList = new JoinStatementList();
int numJoinStatements = 0;
for (int i = 0, n = select.joinStatementList.Length; i < n; i++)
{
if (select.joinStatementList[i] != null)
numJoinStatements++;
if (numJoinStatements <= 64)
newJoinStatementList.Add((JoinStatement)this.VisitJoinStatement(select.joinStatementList[i]));
else
this.HandleError(select.joinStatementList[i], Error.TooManyJoinStatements);
}
select.joinStatementList = newJoinStatementList;
return select;
}
private Select VisitSelect(Select select)
{
WriteStart("select ");
if (select.deterministicSelection)
Write("first ");
if (select.Visible)
Write("visible ");
if (select.validEndState)
Write("end ");
if (this.braceOnNewLine)
{
WriteFinish(string.Empty);
WriteLine("{");
}
else
WriteFinish("{");
In();
for (int i = 0, n = select.joinStatementList.Length; i < n; i++)
this.VisitJoinStatement(select.joinStatementList[i]);
Out();
WriteLine("}");
return select;
}
private Select VisitSelect(Select select)
{
JoinStatementList newJoinStatementList = new JoinStatementList();
for (int i = 0, n = select.joinStatementList.Length; i < n; i++)
{
JoinStatement js = this.VisitJoinStatement(select.joinStatementList[i]);
js.visible = select.visible;
newJoinStatementList.Add(js);
}
select.joinStatementList = newJoinStatementList;
return select;
}
private Select VisitSelect(Select select)
{
if (select == null) return null;
Select result = (Select)select.Clone();
result.joinStatementList = new JoinStatementList();
for (int i = 0, n = select.joinStatementList.Length; i < n; i++)
result.joinStatementList.Add((JoinStatement)this.VisitJoinStatement(select.joinStatementList[i]));
return result;
}
private Select VisitSelect(Select select)
{
JoinStatementList newJoinStatementList = new JoinStatementList();
for (int i = 0, n = select.joinStatementList.Length; i < n; i++)
newJoinStatementList.Add((JoinStatement)this.VisitJoinStatement(select.joinStatementList[i]));
select.joinStatementList = newJoinStatementList;
return select;
}
private Select VisitSelect(Select select)
{
if (select == null) return null;
BasicBlock[] jsBodies = new BasicBlock[select.joinStatementList.Length];
// Traverse each join statement body, with the current continuation
// pointing to the statement following the "select". Remember where
// each join statement body begins so we can wire things up correctly.
for (int i = 0, n = select.joinStatementList.Length; i < n; i++)
{
PushContinuationStack();
this.Visit(select.joinStatementList[i].statement);
// We add an extra block in front of the body because all of the transitions
// within the internal processing of select are atomic. We need for the
// transition to a join statement body to be appropriate for the context
// (atomic or not). Having an extra block here is the simplest way to do
// that. Otherwise, for our tester blocks, we'd need for one outgoing link
// to be atomic, and the other one not. In the case of a select within an
// atomic block, these extra blocks should be optimized away at some point.
jsBodies[i] = new BasicBlock(null, PopContinuationStack());
jsBodies[i].SourceContext = select.joinStatementList[i].statement.SourceContext;
AddBlock(jsBodies[i]);
}
// For each join statement, create a pair of basic blocks - one to
// see whether the join statement is runnable, and another to do
// any "receives" contained in the join pattern list. If there are
// no receives to be processed, the second block may be omitted.
//
// We walk through the list backward to make the wiring easier.
BasicBlock nextTester = null;
for (int i = select.joinStatementList.Length - 1; i >= 0; i--)
{
JoinStatement js = select.joinStatementList[i];
if (i == select.joinStatementList.Length - 1)
{
// If we fall through all of the select test blocks, then we must have
// reached this select statement from within an atomic block. Otherwise,
// we'd know that at least one branch is runnable. In this case, we raise
// a well-known exception and report this as an invalid state.
nextTester = new BasicBlock(Templates.GetStatementTemplate("InvalidBlockingSelect"));
nextTester.SourceContext = select.SourceContext;
AddBlock(nextTester);
nextTester.SkipNormalizer = true;
}
BasicBlock jsTester = new BasicBlock(js);
AddBlock(jsTester);
jsTester.MiddleOfTransition = true;
jsTester.UnconditionalTarget = nextTester;
nextTester = jsTester;
jsTester.ConditionalExpression = Templates.GetExpressionTemplate("JoinStatementTester");
Replacer.Replace(jsTester.ConditionalExpression, "_jsBitMask", (Expression)new Literal((ulong)1 << i, SystemTypes.UInt64));
bool jsHasReceives = false;
for (int j = 0, n = js.joinPatternList.Length; j < n; j++)
{
if (js.joinPatternList[j] is ReceivePattern)
{
jsHasReceives = true;
break;
}
}
//
// We need an executable block if there are receives to be processed
// OR if we need to generate any external events OR if there are
// attributes that we need to deal with on the join statement.
//
if (jsHasReceives || select.visible || js.attributes != null)
{
BasicBlock jsReceiver = new BasicBlock(js);
AddBlock(jsReceiver);
jsReceiver.Attributes = js.Attributes;
jsReceiver.MiddleOfTransition = true;
jsReceiver.SecondOfTwo = true;
jsReceiver.UnconditionalTarget = jsBodies[i];
jsTester.ConditionalTarget = jsReceiver;
}
else
jsTester.ConditionalTarget = jsBodies[i];
}
BasicBlock selectBlock = new BasicBlock(Templates.GetStatementTemplate("SelectStatementProlog"));
if (select.deterministicSelection || select.joinStatementList.Length == 1)
{
// For deterministic selection, we fall directly through to the first
// "tester" block.
selectBlock.UnconditionalTarget = nextTester;
selectBlock.MiddleOfTransition = true;
}
else
{
// For non-deterministic selection, we conditionally branch to a "choice" block if
// more than one join statement is runnable. Otherwise, we fall through to the first
// tester.
BasicBlock choiceHelper = new BasicBlock(Templates.GetStatementTemplate("NDSelectBlock"));
choiceHelper.UnconditionalTarget = nextTester;
AddBlock(choiceHelper);
choiceHelper.MiddleOfTransition = true;
choiceHelper.SkipNormalizer = true;
choiceHelper.SourceContext = select.SourceContext;
selectBlock.UnconditionalTarget = nextTester;
selectBlock.ConditionalExpression = Templates.GetExpressionTemplate("NDSelectTest");
selectBlock.ConditionalTarget = choiceHelper;
selectBlock.MiddleOfTransition = false;
}
AddBlock(selectBlock);
selectBlock.selectStmt = select;
selectBlock.SkipNormalizer = true;
// selectBlock.MiddleOfTransition = true;
selectBlock.SourceContext = select.SourceContext;
CurrentContinuation = selectBlock;
return select;
}
private Select VisitSelect(Select select)
{
if (select == null) return null;
PushSelectStatement(select);
JoinStatementList newJoinStatementList = new JoinStatementList();
int timeoutIndex = -1;
for (int i = 0, n = select.joinStatementList.Length; i < n; i++)
{
if (select.joinStatementList[i].joinPatternList[0] is TimeoutPattern)
{
if (timeoutIndex >= 0)
{
// If we've already seen a "timeout" join statement, then skip
// subsequent ones and report an error.
HandleError(select.joinStatementList[i], Error.TooManyTimeouts);
continue;
}
timeoutIndex = i;
}
JoinStatement newJoinStatement = (JoinStatement)this.VisitJoinStatement(select.joinStatementList[i]);
if (newJoinStatement != null)
newJoinStatementList.Add(newJoinStatement);
}
select.joinStatementList = newJoinStatementList;
// If a timeout is present and it isn't already last, move it to the
// end of the list. This will be helpful during code generation.
if (timeoutIndex >= 0 && timeoutIndex != (select.joinStatementList.Length - 1))
{
JoinStatement temp;
temp = select.joinStatementList[select.joinStatementList.Length - 1];
select.joinStatementList[select.joinStatementList.Length - 1] = select.joinStatementList[timeoutIndex];
select.joinStatementList[timeoutIndex] = temp;
}
if (select.joinStatementList.Length == 1)
select.deterministicSelection = true;
PopSelectStatement();
if (select.joinStatementList.Length == 0)
return null;
return select;
}
private void PushSelectStatement(Select select)
{
selectStatementStack.Push(select);
}
private Select VisitSelect(Select select)
{
if (select == null) return null;
for (int i = 0, n = select.joinStatementList.Length; i < n; i++)
select.joinStatementList[i] = (JoinStatement)this.VisitJoinStatement(select.joinStatementList[i]);
return select;
}