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Optimize DFG De Morgan patterns (#6090) 

It's ok if the replaced vertex has multiple sinks, this pattern cannot
increase the size of logic even then.
This commit is contained in:
Geza Lore 2025-06-15 16:00:11 +01:00 committed by GitHub
parent 47f5a6a52b
commit bca2e2c16e
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GPG Key ID: B5690EEEBB952194
1 changed files with 4 additions and 4 deletions
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8
src/V3DfgPeephole.cpp
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@ -895,8 +895,8 @@ class V3DfgPeephole final : public DfgVisitor {
DfgVertex* const rhsp = vtxp->rhsp();
FileLine* const flp = vtxp->fileline();
// Bubble pushing
if (!vtxp->hasMultipleSinks() && !lhsp->hasMultipleSinks() && !rhsp->hasMultipleSinks()) {
// Bubble pushing (De Morgan)
if (!lhsp->hasMultipleSinks() && !rhsp->hasMultipleSinks()) {
if (DfgNot* const lhsNotp = lhsp->cast<DfgNot>()) {
if (DfgNot* const rhsNotp = rhsp->cast<DfgNot>()) {
APPLYING(REPLACE_AND_OF_NOT_AND_NOT) {
@ -964,8 +964,8 @@ class V3DfgPeephole final : public DfgVisitor {
DfgVertex* const rhsp = vtxp->rhsp();
FileLine* const flp = vtxp->fileline();
// Bubble pushing
if (!vtxp->hasMultipleSinks() && !lhsp->hasMultipleSinks() && !rhsp->hasMultipleSinks()) {
// Bubble pushing (De Morgan)
if (!lhsp->hasMultipleSinks() && !rhsp->hasMultipleSinks()) {
if (DfgNot* const lhsNotp = lhsp->cast<DfgNot>()) {
if (DfgNot* const rhsNotp = rhsp->cast<DfgNot>()) {
APPLYING(REPLACE_OR_OF_NOT_AND_NOT) {