Clocked thread SC_CTHREAD exclusion during initialization phase

[SystemCInDepth]

Hi,

I have a very basic question "Why clocked threads are excluded from the initialization phase when processes are added to the runnable queue" ?

Thanks !

[Philipp A Hartmann]

Because clocked threads are sensitive to an explicit clock.  This clock does not have to be active during the start of the simulation.

Greetings from Duisburg,
  Philipp

[SystemCInDepth]

Hi Philipp

So, if  SC_METHOD or SC_THREADis sensitive to some clock event. It will also be excluded from the initialization phase. Is it ?

Thanks !

[Philipp A Hartmann]

2 minutes ago, SystemCInDepth said:

So, if  SC_METHOD or SC_THREADis sensitive to some clock event. It will also be excluded from the initialization phase. Is it ?

No.  These process flavors are subject to the dont_initialize() setting.

See IEEE 1666-2011, 4.2.1.1, step (b):

Quote

Add every method and thread process instance in the object hierarchy to the set of runnable
processes, but exclude those process instances for which the function dont_initialize has been
called, and exclude clocked thread processes.

Greetings from Duisburg,
 Philipp

[SystemCInDepth]

2 minutes ago, Philipp A Hartmann said:

No.  These process flavors are subject to the dont_initialize() setting.

See IEEE 1666-2011, 4.2.1.1, step (b):

Greetings from Duisburg,
 Philipp

I have read that and thats why I am curious about to know the reason behind this. As Method and thread are allowed to be added to the runnable queue with clock on sensitivity but SC_CTHREAD are excluded having the same clock on sensitivity. 

[apfitch]

Hi Mr SystemCInDepth,

   I think it's important to realise that SC_CTHREAD is special, in that the specified sensitivity is a clock (the rising or falling edge event of a bool or sc_logic).

There's no such thing as a "clock" for SC_METHOD and SC_THREAD - just events on channels such as sc_signal, sc_fifo, or any other channel that implements an event.

So I would not say

Quote

As Method and thread are allowed to be added to the runnable queue with clock

because an SC_METHOD or an SC_THREAD does not have a clock. That's what Philipp meant when he said

Quote

clocked threads are sensitive to an explicit clock

Does that make it clearer?

regards

Alan