* Fix broken support of unassigned virtual interfaces
Unassigned virtual interface support added by #6245 is broken - PR marks
dead module as alive - we can't do that as once a module is dead it
needs to remain dead because earlier steps (e.g. port resolution) have
already been skipped.
This commit handles unassigned virtual interfaces at the beginning of
first pass of LinkDot (so it is never marked as dead, and no linking
steps are getting skipped).
Fixes#6253.
* Apply suggestions from code review
Co-authored-by: Wilson Snyder <wsnyder@wsnyder.org>
* Apply 'make format'
* Revert add of redundant iterateChildren() call
* Add original test case
---------
Co-authored-by: Wilson Snyder <wsnyder@wsnyder.org>
Co-authored-by: github action <action@example.com>
The previous algorithm was designed to handle the general case where a
full control flow path predicate is required to select which value to
use when synthesizing control flow join point in an always block.
Here we add a better algorithm that tries to use the predicate of
the closest dominating branch if the branch paths dominate the joining
paths. This is almost universally true in synthesizable logic (RTLMeter
has no exceptions), however there are cases where this is not
applicable, for which we fall back on the previous generic algorithm.
Overall this significantly simplifies the synthesized Dfg graphs and
enables further optimization.
* Skip profiling tests on non-glibc platforms
* Enforce dumb terminal in tests
* Include POSIX headers whenever __unix__ macro is defined
* Treat no procfs as normal condition
* Respect MAKE variable when running make
There were a couple corner case bugs in V3Inline, and one in Dfg when
dealing with inlining of modules/variables.
V3Inline:
- Invalid code generated when inlining an input that also had an
assignment to it (Throws an ASSIGNIN, but this is sometimes reasonable
to do, e.g. hiererchical reference to an unonnected input port)
- Inlining (aliasing) publicly writeable input port.
- Inlining forcable port connected to constant.
Dfg:
- Inining publicly writeable variables
The tests that cover these are the same and fixing one will trigger the
other bug, so fixing them all in one go. Also cleanup V3Inline to be less
out of order and rely less on unique APIs only used by V3Inine (will
remove those in follow up patch).
Small step towards #6280.
This patch adds DfgLogic, which is a vertex that represents a whole,
arbitrarily complex combinational AstAlways or AstAssignW in the
DfgGraph.
Implementing this requires computing the variables live at entry to the
AstAlways (variables read by the block), so there is a new
ControlFlowGraph data structure and a classical data-flow analysis based
live variable analysis to do that at the variable level (as opposed to
bit/element level).
The actual CFG construction and live variable analysis is best effort,
and might fail for currently unhandled constructs or data types. This
can be extended later.
V3DfgAstToDfg is changed to convert the Ast into an initial DfgGraph
containing only DfgLogic, DfgVertexSplice and DfgVertexVar vertices.
The DfgLogic are then subsequently synthesized into primitive operations
by the new V3DfgSynthesize pass, which is a combination of the old
V3DfgAstToDfg conversion and new code to handle AstAlways blocks with
complex flow control.
V3DfgSynthesize by default will synthesize roughly the same constructs
as V3DfgAstToDfg used to handle before, plus any logic that is part of a
combinational cycle within the DfgGraph. This enables breaking up these
cycles, for which there are extensions to V3DfgBreakCycles in this patch
as well. V3DfgSynthesize will then delete all non synthesized or non
synthesizable DfgLogic vertices and the rest of the Dfg pipeline is
identical, with minor changes to adjust for the changed representation.
Because with this change we can now eliminate many more UNOPTFLAT, DFG
has been disabled in all the tests that specifically target testing the
scheduling and reporting of circular combinational logic.
NBAs targeting a variable in a different scope are now allocated
temporary variables for captured values in the scope of the NBA, not the
scope of the target variable.
Fixes#6286
Wilson Snyder
Krzysztof Bieganski
Szymon Gizler
Geza Lore
Ryszard Rozak
Igor Zaworski
Aleksander Kiryk
Artur Bieniek
Mateusz Gancarz