compiler doubt

Question

what is semantic stack? and where it is used?

Answer 1

1. To make the stack directly accessible to the semantic routines. Using this approach, the action routines take their parameters from the top of the stack rather than receiving them explicitly when they are called. Similarly, any semantic record produced by an action routine is pushed onto the stack after the parameters are removed. It is called an Action-Controlled Semantic Stack.
2. it is mainly used in semantic routines