For NBAs that might execute a dynamic number of times in a single
evaluation (specifically: those that assign to array elements inside
loops), we introduce a new run-time VlNBACommitQueue data-structure
(currently a vector), which stores all pending updates and the necessary
info to reconstruct the LHS reference of the AstAssignDly at run-time.
All variables needing a commit queue has their corresponding unique
commit queue.
All NBAs to a variable that requires a commit queue go through the
commit queue. This is necessary to preserve update order in sequential
code, e.g.:
a[7] <= 10
for (int i = 1 ; i < 10; ++i) a[i] <= i;
a[2] <= 10
needs to end with array elements 1..9 being 1, 10, 3, 4, 5, 6, 7, 8, 9.
This enables supporting common forms of NBAs to arrays on the left hand
side of <= in non-suspendable/non-fork code. (Suspendable/fork
implementation is unclear to me so I left it unchanged, see #5084).
Any NBA that does not need a commit queue (i.e.: those that were
supported before), use the same scheme as before, and this patch should
have no effect on the generated code for those NBAs.
No functional change. Postpone the conversion of all AstAssignDlys that
use the 'VdlySet' scheme for array LHSs until after the complete
traversal of the netlist. The next patch takes advantage of this by
using some extra information also gathered through the traversal to
change the conversion.
AstAssignDlys inside suspendable or fork are not deferred and are
processed identical to the previous version.
There are some TODOs in this patch that are fixed in the next patch.
Output code perturbed due to variable ordering.
MULTIDRIVEN message ordering perturbed due to processing order change.
This adheres more to the wording used in IEEE 1800-2017 22.5.1,
specifying the join operator to be more of a delimiter than join:
> A `` delimits lexical tokens without introducing white space,
> allowing identifiers to be constructed from arguments.
Before, string RHS arguments to the join operator were silently dropped.
Signed-off-by: Arkadiusz Kozdra <akozdra@antmicro.com>
Todd Strader
Wilson Snyder
Geza Lore
Arkadiusz Kozdra
Yinan Xu
Bartłomiej Chmiel
Aleksander Kiryk
Iztok Jeras
Paul Wright
Krzysztof Bieganski
Andrew Nolte
Szymon Gizler
Fuad Ismail
Ryszard Rozak