S-Attributed SDTs can be naturally evaluated during which type of parsing?
Since S-attributed definitions use only synthesized attributes, semantic actions can execute immediately whenever a production reduction occurs on the LR stack.
Consider the SDD: E -> E1 + T { E.val = E1.val + T.val }. What type of attribute is E.val?
E.val is computed from child attributes E1.val and T.val, making it a Synthesized attribute.
Which intermediate code representation uses explicit pointers to operational tuples and eliminates redundant temporary variable names?
Indirect Triples use an array of pointers to triple instructions, allowing code reordering without changing internal instruction operand references.
In Three-Address Code (TAC), how many memory operands at most can appear on the right hand side of any instruction?
Each TAC instruction has at most 3 addresses in total (e.g. x = y op z), meaning at most 2 source operands on the right-hand side and 1 result on the left.
What is the Quadruple structure representation for Three-Address Code instruction x = y + z?
A Quadruple record consists of four fields: (op, arg1, arg2, result). For x = y + z, it is stored as (+, y, z, x).