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Merge 51a377be44 into 9d0cdb8551

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Zachary Snow 2026-05-23 11:42:48 +08:00 • committed by GitHub
commit ec42748e66
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6 changed files with 84 additions and 10 deletions
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13
frontends/ast/simplify.cc
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@ -1434,6 +1434,8 @@ bool AstNode::simplify(bool const_fold, int stage, int width_hint, bool sign_hin
}
if (type == AST_CELL) {
// when a module lookup is suggested, any port connection that is not a
// plain identifier will be indirected through a new wire
bool lookup_suggested = false;
for (auto& child : children) {
@ -1456,7 +1458,7 @@ bool AstNode::simplify(bool const_fold, int stage, int width_hint, bool sign_hin
continue;
}
if (elem->type == AST_MEMORY)
// need to determine is the is a read or wire
// need to determine is the is a read or write
lookup_suggested = true;
else if (elem->type == AST_WIRE && elem->is_signed && !value->children.empty())
// this may be a fully sliced signed wire which needs
@ -1466,6 +1468,15 @@ bool AstNode::simplify(bool const_fold, int stage, int width_hint, bool sign_hin
else if (contains_unbased_unsized(value.get()))
// unbased unsized literals extend to width of the context
lookup_suggested = true;
else if (value->type == AST_TO_UNSIGNED)
// inner expression may be signed by default
lookup_suggested = true;
else if (value->type == AST_CONCAT) {
// concat of a single expression is equivalent to $unsigned;
// concats could also contain one or references to memories,
// which may ambiguously be reads or writes
lookup_suggested = true;
}
}
}