Consider the intermediate code given below. (1) i=1 (2) j=1 (3) t1 = 5 * i (4)…

Solution overview: construct the control-flow graph by identifying leaders, forming basic blocks, then counting nodes and edges (including explicit entry and exit nodes).

• Leaders (statement numbers): first statement (1); targets of jumps (3) and (2); statement following the conditional at (9) is (10). So leaders are 1, 2, 3, and 10.

• Basic blocks formed from leaders:

  • Block 1: statement (1) alone.

  • Block 2: statement (2) alone.

  • Block 3: statements (3) through (9) (includes the conditional at (9)).

  • Block 4: statements (10) and (11).

• Count nodes: 4 basic blocks plus an explicit entry and exit node gives 6 nodes.

• Count edges (succinctly):

  • Entry → Block containing (1).

  • Block (1) → Block (2).

  • Block (2) → Block (3).

  • From the conditional at (9) inside Block (3): true branch goes back to the start of Block (3) (a self-loop).

  • From the conditional at (9): false branch goes to Block (4) (statement (10)).

  • From the conditional at (11) in Block (4): true branch goes to Block (2).

  • From the conditional at (11): false branch goes to Exit.

• Total edges counted above = 7.

Answer: 6 nodes and 7 edges.