systemc: Switch to using predefined messages for datatypes.

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

Change-Id: I92dd52f62462b864264217bb81f3ff1dcec020bf
Reviewed-on: https://gem5-review.googlesource.com/c/13331
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Switch to using predefined messages for utils.

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

Change-Id: I932b7206fc16181d01a0d5b7441ce617b30e5365
Reviewed-on: https://gem5-review.googlesource.com/c/13328
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Implement general and VCD trace support.

This doesn't include WIF trace support, but does make allowances for
adding it in the future.

Change-Id: Ifb62f40a7d8a13e94463930a44ac4b1cf41e3009
Reviewed-on: https://gem5-review.googlesource.com/c/12826
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Ensure SC_LONG_64 is defined and available.

The datatype code was checking if SC_LONG_64 was defined to determine
if a long was 64 bits. The code that would define that value was
dropped when porting over from the Accellera implementation, and so
the wrong code was being included. This change both makes those checks
look at the *value* of SC_LONG_64 to ensure that it's not missing by
accident, and assigns it a value in sc_fxdefs.hh.

Change-Id: Ie9bb1146452a3db1d9d99c0db575098bb06463ff
Reviewed-on: https://gem5-review.googlesource.com/c/12616
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: "Fix" some error message formatting.

These changes make the output match what Accellera outputs so that the
tests will pass.

Change-Id: I1260cec35fa39586fbef39047b9da4ff3c03b3ed
Reviewed-on: https://gem5-review.googlesource.com/c/12592
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Fix a typo/bug in sc_int_base.hh.

When being turned into gem5 coding style, a pair of "!" operators were
dropped, reversing the behavior of the functions involved.

Change-Id: Ife795c22aff953c5ab592e7baa3a5e1c15e63c84
Reviewed-on: https://gem5-review.googlesource.com/c/12591
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Adjust some error messages to match Accellera.

Those messages include an error number in the Accellera implementation.
Add those numbers to gem5 so it's easier to check against golden
reference output for the regression tests.

Change-Id: I35054dd187e86a87eb177f4695d61044c58ce262
Reviewed-on: https://gem5-review.googlesource.com/c/12450
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

Systemc: Port over all of the systemc "datatype" headers.

These are the headers originally written by Accellera with a few
modifications. Most significantly, I went through and mostly (but not
entirely) manually editted them to conform to gem5 style and to be
more self consistent. Second, I resolved some macros which optionally
select features. I removed support for deprecated functions, and
otherwise enabled everything.

The actual implementation behind these headers will also be ported
over, but in a subsequent change.

Change-Id: I203d3f6c8a3af9120b946001d01defbb0643a6b6
Reviewed-on: https://gem5-review.googlesource.com/10843
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Add systemc and systemc.h header files.

These are the header files as defined by the standard, although some
predefined channel types and most of the sc_dt namespace have yet to be
stubbed out, and so those portions are excluded.

Change-Id: Ic70f887c06e591974a4265c820eb0fdfa740d19a
Reviewed-on: https://gem5-review.googlesource.com/10838
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

systemc: Seperate the "external" header interface.

Most (but not all) of the SystemC headers are part of the "external"
interface that an existing, standard compliant module would include
through <systemc.h> or <systemc>. Since those follow slightly different
rules (relative includes, no gem5 includes), this change separates them
out so that they're easier to identify.

Also, this change moves the other files into a "core" subdirectory,
with the intention to add a "dt", aka data type, directory some time in
the future when those standard defined types are implemented.

Change-Id: Ida63f9cc0bc0431024d4dd691cc5b22b944a99a8
Reviewed-on: https://gem5-review.googlesource.com/10835
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>