Modify the grammar of Figure 15.6 to generate jump code for Boolean expressions, as described in Section 6.4.1. You should assume short circuit evaluation.

Figure 15.6:

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reg_names : array [0..k-1] of register.name := ["r1, "r2" .., "rk"] -- ordered set of temporaries program + stmt stmt.next.free_reg := 0 program.code := ["main:"] + stmt.code + ["goto exit"] while : stmt expr stmtz stmtz expr.next.free_reg := stmt2.next.free_reg := stmt3.next.free.reg := stmtj.next.free_reg L1:= new.label(); L2 := newJabel() stmtj.code := ["goto" L1] + [L2 ":"] + stmt2.code + [L1 ":"] + expr.code + ["if" expr.reg "goto" L2] + stmt3.code if : stmti expr stmt2 stmtz stmtą expr.next_free_reg := stmt2.next.free reg := stmt3.next.free_reg := stmt4.next.free_reg := stmtj.next.free-reg L1:= new.label); L2 := newJabel() stmtj.code := expr.code + ["if" expr.reg "goto" L1] + stmt3.code + ["goto" L2] + [L1 ":"] + stmt2.code + [L2 ":"] + stmtą.code assign : stmt - id expr stmtz expr.next.free_reg := stmt2.next.freereg := stmtj.next.free.reg stmtı.code := expr.code + [id.stp→name ":=" expr.reg] + stmt2.code read : stmt + id, idz stmt2 stmtj.code := ["a1 := &" id.stp→name] + ["call" if id2.stp>type = int then "readint" else ...] + [idz.stp→name ":= rv"] + stmt2.code %3D -- file write : stmt → id expr stmt2 expr.next_free_reg := stmt2.next.freereg := stmtj.next.free.reg stmtj.code := ["a1 := &" id.stp→name] + ["a2 :=" expr.reg] + ["call" if id.stp type = int then "writeint" else ..] + stmt2.code -- file -- value writeln : stmti + id stmtz stmtj.code := ["a1 := &" id.stpname] + ["call writeln"] + stmt2.code null : stmt €