Techniques are disclosed for initializing a representation of a cache in a microprocessor design under test. The cache representation includes a plurality of cache entries, each of which is uniquely referenced by an address-way pair. A test case includes a plurality of cache initialization records, each of which includes a cache entry reference and an initial cache entry value. Each cache entry reference includes an address identifier and a way identifier. An initializer reads the cache initialization records and uses the records which contain valid address-way pairs to initialize cache entries in the cache representation. The initializer then uses the remaining records, in which the way identifier is an invalid (e.g., null) value, to initialize cache entries in the cache representation. Valid way identifiers are selected for these records in a manner which ensures that cache entries are not initialized more than once.