CS 2420-20 Homework 18

Due: Thursday, March 31st, 2011 9:10am

Suppose a garbage-collected interepreter uses the following three kinds of records:

• Tag 1: a record containing two pointers
• Tag 2: a record containing one pointer and one integer
• Tag 3: a record containing one integer

The interpreter has one register, which always contains a pointer, and a memory pool of size 22. The allocator/collector is a two-space copying collector, so each space is of size 11. Records are allocated consecutively in to-space, starting from the first memory location, 0.

The following is a snapshot of memory just before a collection where all memory has been allocated:

• Register: 8
• To space: 1 3 8 3 0 2 3 7 2 0 8

What are the values in the register and the new to-space (which is also addressed starting from 0) after collection? Assume that unallocated memory in to-space contains 0.