编译原理学习笔记（十三）

课堂题目

1．把下列语句翻译成三地址代码
while a > 10 do
if b = 100 then
while a < 20 do
a := a + b – 1

2．把下列语句翻译成三地址代码
if a>10 and c>d then
if b=100 then a := a / b
else a := a * b

题目答案

题目一：
(1) if a>10 goto (3)
(2) goto -
(3) if b==100 goto (5) M3.stat
(4) goto (1) M1.stat
(5) if a<20 goto (7) M5.stat
(6) goto (1) M1.stat
(7) t1 := a+b
(8) t2 := t1-1
(9) a := t2
(10) goto (5) M4.stat
(11) goto (1) M1.stat

题目二：
(1) if a>10 goto (3)
(2) goto –
(3) if c>d goto (5) M1.stat
(4) goto –
(5) if b==100 goto (7) M2.stat
(6) goto (10) M3.stat
(7) t1 := a/b
(8) a := t1
(9) goto -
(10) t2 := a*b
(11) a := t2