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Optimize constant folding in wide expression expansion (#6381) 

Do not apply V3Const in V3Expand after a function if nothing was
expanded in it.

Also fix statistics counter while at it.

Inspired by #6379, follow up from #6111
This commit is contained in:
Geza Lore 2025-09-10 11:45:08 +01:00 committed by GitHub
parent 220a3faf7c
commit 7f945bf89e
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GPG Key ID: B5690EEEBB952194
1 changed files with 4 additions and 3 deletions
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7
src/V3Expand.cpp
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@ -95,8 +95,8 @@ class ExpandVisitor final : public VNVisitor {
bool doExpandWide(AstNode* nodep) {
if (isImpure(nodep)) return false;
++m_statWides;
if (nodep->widthWords() <= v3Global.opt.expandLimit()) {
++m_statWides;
m_statWideWords += nodep->widthWords();
return true;
} else {
@ -393,10 +393,11 @@ class ExpandVisitor final : public VNVisitor {
VL_RESTORER(m_nTmps);
m_funcp = nodep;
m_nTmps = 0;
const VDouble0 statWidesBefore = m_statWides;
iterateChildren(nodep);
// Constant fold here, as Ast size can likely be reduced
if (v3Global.opt.fConstEager()) {
// Constant fold here if anything was expanded, as Ast size can likely be reduced
if (v3Global.opt.fConstEager() && m_statWides != statWidesBefore) {
AstNode* const editedp = V3Const::constifyEditCpp(nodep);
UASSERT_OBJ(editedp == nodep, editedp, "Should not have replaced CFunc");
}