The lowerDistConstraints() function was not recursing into ConstraintIf
nodes, causing dist operators inside if-else blocks to remain unlowered
and trigger an internal error when ConstraintExprVisitor encountered them.
Fix by adding recursive handling of ConstraintIf nodes in lowerDistConstraints:
- Check for AstConstraintIf nodes before AstConstraintExpr
- Recursively process thensp() and elsesp() branches
- This ensures all dist operators are lowered regardless of nesting
Test case: t_randomize_dist_conditional.v demonstrates conditional dist:
constraint c {
if (randd) {
x dist { 8'd0 := 1, 8'd255 := 3 }; // 25% / 75%
} else {
x dist { 8'd0 := 3, 8'd255 := 1 }; // 75% / 25%
}
}
Fixes#7221
Also add array bounds and struct/union member counts to trace pushPrefix
(not used by vcd/fst/saif). Together these improve consistency in some
waveform formats.
- Allow reordering pure statements with DPI import calls iff no public
variables (including those read via a DPI export) are involved. This
ensures the DPI import can't observe the reordering
- Allow reordering of pure statements with AstDisplay and AstStop. This
requires an assumption that AstDisplay and AstStop will not read or
write model state other than via a VarRef explicitly present int the
Ast.
Overall this allows eliminating a lot of conditionals around assertions,
which were previously not possible.
Introduce new pass that converts impure expressions, or those with
function and method calls into simple assignment statements. Please see
the blurb at the top of the file why this is useful and how it works.
In particular currently it enables more Dfg optimization as functions
will be inlined without AstExprStmt.
Ideally we should enforce this lowering is applied to every procedural
statement (there are still a handful of exceptions). With that, long
term with this pass + #6820, there should be no need to ever use an
AstExprStmt past this new lowering pass, which should enable more easier
optimization down the line.
Also ideally this should be run earlier. Currently it's after V3Tristate
as that calls pinReconnectSimple so we don't have to touch Cell ports.
Currently disabled when code coverage is enabled due to #7119.
Pawel Kojma
Yilou Wang
Wilson Snyder
Rahul Behl
em2machine
Veripool API Bot
Christian Hecken
Rahul Behl
Geza Lore
Julian Carrier
Ryszard Rozak
Nick Brereton
Igor Zaworski
jalcim
Kamil Danecki