public void definePredicateInAlt(int currentAlt, PredAST predAST) {
		actions.add(predAST);
		alt[currentAlt].actions.add(predAST);
		if ( g.sempreds.get(predAST)==null ) {
			g.sempreds.put(predAST, g.sempreds.size());
		}
	}
Lexer actions are numbered across rules 0..n-1
tool/src/org/antlr/v4/tool/Rule.java