systemc: Get rid of leftovers from unimplemented warnings past.

These warnings were removed when the functionality they warned about
was implemented, but there were some leftovers like unnecessary
includes and some helper functions which hid gem5 specific headers
from the ext directory.

Change-Id: Ic886ac0f1264687524e3a7b7eaab8836f318a5a2
Reviewed-on: https://gem5-review.googlesource.com/c/13398
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Switch to using predefined messages for core.

Create and use predefined messages for core which match the ones
Accellera uses.

Change-Id: I05b1398933f753946d5917f39d0f39c7cb45ed9f
Reviewed-on: https://gem5-review.googlesource.com/c/13323
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Distinguish internal events from normal sc_events.

The internal events aren't supposed to show up in the namespace or as
children of objects.

Change-Id: Id04b9bfe2e1f8f216390dd989797558eaf33d715
Reviewed-on: https://gem5-review.googlesource.com/c/13309
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Implement sc_get_curr_process_handle().

The implementation is fairly trivial, but the pieces it relies on
weren't always available.

Change-Id: Ie77168ff336febd3ebe22c400f2b1f133e43aca7
Reviewed-on: https://gem5-review.googlesource.com/c/12973
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Improve handling of empty process handles.

Most had checks, but didn't print any message. throw_it needed a check
as well.

Change-Id: I916c837112f9b27852583f01b3e16a6f53d5e7ca
Reviewed-on: https://gem5-review.googlesource.com/c/12440
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Make sc_process_b less hokey, and make WAIT* work.

This change puts sc_process_b into the inheritance hierarchy for the
Process types. It also adds the nonstandard sc_set_location function
and calls it from the nonstandard WAIT* macros.

Change-Id: Ic997dcf74d262774dd7b53504146e372e03af2e0
Reviewed-on: https://gem5-review.googlesource.com/12259
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Fix a "problem" with kill/reset exceptions.

Despite what it says in the spec, the proc_ctrl compliance test throws
a copy of the reset exception it catches, not the original. Because of
that, the code in the kernel which catches the exception gets the base
class, not the derived class with overridden virtual methods, etc.
This happens to work for the Accellera implementation because they
manipulate members of the base class itself which are preserved despite
this bug. To make the test work, we imitate their implementation, even
though it exposes more implementation details through the header files.

Change-Id: I7ed9818c0552869ec790cb7f7bfbe365ade5e49c
Reviewed-on: https://gem5-review.googlesource.com/12045
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Implement sc_get_current_process_handle's other personality.

When run during simulation, sc_get_current_process_handle returns a
handle for the currently running process or a invalid handle if no
process is running (ie sc_main is running).

When run during elaboration, it returns a handle to the most recently
created process. This second context is what this change handles.

Change-Id: I3fb247b9b7bf83891c782966cfef474753159158
Reviewed-on: https://gem5-review.googlesource.com/12030
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Partially implement the scheduler.

This change implements the "evaluate" part of the delta cycles, and
sketches out a function to run delta cycles and the initialization
phase. The kernel object now schedules an event at time zero which
runs the initialization phase.

Also, some small places which were stubbed out pending a way to check
the currently running process have been filled in now that that's
being tracked.

Change-Id: I6899569eb0195ff1c059fa4e68e90ef162b2f2df
Reviewed-on: https://gem5-review.googlesource.com/11709
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Fill out sc_process_handle and create Process classes.

The sc_process_handle class now primarily delegates to a Process object
it points at. The Process object does book keeping as far as its
internal state, but doesn't yet have a way to run its target function
or to schedule itself or inject exceptions into its context of
execution.

Change-Id: I98389778abe29aa26e3e3a91bf02e6721acc8a9c
Reviewed-on: https://gem5-review.googlesource.com/11613
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Add a minimal version of the deprecated sc_process_b.

This type is deprecated, but some tests still rely on it. This change
adds just enough of it to satisfy the tests, and also the several
different mechanisms for retrieving the sc_process_b which refers to
the currently active process.

Change-Id: Id122ae5df23744b5de1e1c97573412f97a73b77a
Reviewed-on: https://gem5-review.googlesource.com/11351
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Add the nonstandard variable sc_allow_process_control_corners.

This variable controls what happens in some situations which are left
as undefined in the spec. It's behavior is explained in a big comment
in the Accellera implementation. Since it's used in the regression
tests, we need to at least have that variable so they'll compile and
link properly.

Change-Id: I1ac4592641be3d9dd10e7bf6144704a6fac1b2d4
Reviewed-on: https://gem5-review.googlesource.com/11186
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Stub out the sc_process_handle class.

Change-Id: I2250ccb369e0a5f2b9172d35662a9ce5e41ab1c1
Reviewed-on: https://gem5-review.googlesource.com/10836
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>