Syntax-Directed Translation

One or more correct

• AThe languages P and Q are the same
• BSDD2 is S-attributed and contains only synthesized attributes
• CSDD1 is L-attributed and contains only inherited attributes
• DThe specifications of SDD1 and SDD2 are such that the same entries get added to the symbol table

Single correct

• ARule 1 is S-attributed and L-attributed; Rule 2 is S-attributed and not L-attributed; Rule 3 is neither S-attributed nor L-attributed
• BRule 1 is neither S-attributed nor L-attributed; Rule 2 is S-attributed and L-attributed; Rule 3 is S-attributed and L-attributed
• CRule 1 is neither S-attributed nor L-attributed; Rule 2 is not S-attributed and is L-attributed; Rule 3 is S-attributed and L-attributed
• DRule 1 is S-attributed and not L-attributed; Rule 2 is not S-attributed and is L-attributed; Rule 3 is S-attributed and L-attributed

S → DHTU      { S.val = D.val + H.val + T.val + U.val; }
D → "M" D1    { D.val = 5 + D1.val; }
D → ε         { D.val = −5; }
H → "L" H1    { H.val = 5 * 10 + H1.val; }
H → ε         { H.val = −10; }
T → "C" T1    { T.val = 5 * 100 + T1.val; }
T → ε         { T.val = −5; }
U → "K"       { U.val = 5; }

Single correct

• A45
• B50
• C55
• D65

One or more correct

• AAn attribute grammar is a syntax-directed definition (SDD) in which the functions in the semantic rules have no side effects
• BThe attributes in a L-attributed definition cannot always be evaluated in a depth-first order
• CSynthesized attributes can be evaluated by a bottom-up parser as the input is parsed
• DAll L-attributed definitions based on LR(1) grammar can be evaluated using a bottom-up parsing strategy

Numerical answer

Answer key coming soon

Numerical answer

Answer key coming soon

P → D* E*
D → int ID  {record that ID.lexeme is of type int}
D → bool ID {record that ID.lexeme is of type bool}
E → E1 + E2 {check that E1.type = E2.type = int; set E.type := int}
E → !E1     {check that E1.type = bool; set E.type := bool}
E → ID      {set E.type := int}

Single correct

• AThe actions can be used to correctly type-check any syntactically correct program.
• BThe actions can be used to type-check syntactically correct integer variable declarations and integer expressions.
• CThe actions can be used to type-check syntactically correct boolean variable declarations and boolean expressions.
• DThe actions will lead to an infinite loop.

Answer key coming soon

Single correct

• ABoth Rule 1 and Rule 2 are L-attributed.
• BOnly Rule 1 is L-attributed.
• COnly Rule 2 is L-attributed.
• DNeither Rule 1 nor Rule 2 is L-attributed.

Answer key coming soon

Single correct

• A$X_1 = L, X_2 = T, X_3 = L_1, X_4 = L$
• B$X_1 = T, X_2 = L, X_3 = L_1, X_4 = T$
• C$X_1 = L, X_2 = L, X_3 = L_1, X_4 = T$
• D$X_1 = T, X_2 = L, X_3 = T, X_4 = L_1$

Single correct

• A1 3 2
• B2 2 3
• C2 3 1
• Dsyntax error

Answer key coming soon