What is the maximum number of operands in a standard Three-Address Code instruction?
A standard TAC instruction has at most three operands, typically of the form $x = y op z$. The exact number of memory operands depends on the target representation, so the standard bound is on operands, not specifically memory operands.
Convert the statement 'if (a < b) $x = 1$; else x = 2;' into Three-Address Code using conditional jumps. What is the minimum number of TAC instructions?
TAC:
1: if a < b goto 4
2: $x = 2$
3: goto 5
4: $x = 1$
5: (next instruction)
Total = 4 instructions.
What is the primary difference between an Abstract Syntax Tree (AST) and a Parse Tree (Concrete Syntax Tree)?
An AST condenses the parse tree by discarding pure syntax tokens (e.g. punctuation, keywords) and retaining only operator-operand relationships.
In intermediate code generation using backpatching, what are 'truelist' and 'falselist' synthesized attributes used for?
In backpatching, truelist contains lists of jump instructions to be patched when a Boolean expression evaluates to true, and falselist handles the false evaluation path.
Which intermediate code format represents expressions as a syntax tree where operators are interior nodes and operands are children?
In an AST, operators form interior nodes and operands form child nodes, providing a structural intermediate representation.