Topic: register allocation by usage counts

topics > computer science > programming > Group: code generation

memory management

memory management by reference counting
register allocation
register allocation by use-def graphs

Subtopic: usage counts up

Quote: usage count is number of distinct references to a value in a program [»freiRA11_1974]
Quote: last use of value when its usage count drops to zero [»freiRA11_1974]
Quote: a register's value should be discarded after last use [»freiRA11_1974]
Quote: usages counts used by Gries for last use of temporaries [»freiRA11_1974]

Subtopic: using usage counts up

Quote: spill the register containing value with the lowest usage count [»freiRA11_1974]
Quote: assign registers using bottom-up usage counts for variable addresses and values [»webeM2_1980]
Quote: allocates registers for loop by two passes; second pass uses usages counts from first pass [»webeM2_1980]
Quote: min usage count propagated at top of if statements (a merge); current usage count propagated at bottom (a fork) [»webeM2_1980]
Quote: during code generation model machine state by value assignments and their usage counts [»freiRA11_1974]

Subtopic: usage count vs LRU up

Quote: spilling registers by least usage count better than LRU or least recently loaded [»freiRA11_1974, OK]
Quote: usage counts better than least-recent information since it depends on future instead of past history [»freiRA11_1974]

Subtopic: pointer rotation up

Quote: straight-line code that preserves reference counts and does not create records is implemented by a pointer rotation

Related Topics up

Group: memory management   (11 topics, 367 quotes)

Topic: memory management by reference counting (23 items)
Topic: register allocation (28 items)
Topic: register allocation by use-def graphs
(9 items)

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