Rematerialize zero literals

libyul/optimiser/Metrics.cpp

@@ -158,6 +158,10 @@ void CodeCost::operator()(Literal const& _literal)
 	case LiteralKind::Number:
 		for (u256 n = u256(_literal.value.str()); n >= 0x100; n >>= 8)
 			cost++;
+		if (valueOfLiteral(_literal) == 0)
+			if (auto evmDialect = dynamic_cast<EVMDialect const*>(&m_dialect))
+				if (evmDialect->evmVersion().hasPush0())
+					--m_cost;
 		break;
 	case LiteralKind::String:
 		cost = _literal.value.str().size();