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Logical Operations
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CF=0, OF=0
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shift
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CF=value of last bit shifted out; OF=0
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INC, DEC
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OF and ZF may change, CF unchanged
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cmpl b, a
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a-b result not stored anywhere
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testq b, a
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a&b result not stored anywhere
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Enough registers
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No reference to & so no need to go to memory
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No arrays, structures
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3 cases
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compulsory, capacity, conflict
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How to reduce miss
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block size++, associativity++, cache size++
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Reducing miss penalty
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write through (update all) vs write back (update when needed)
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multilevel cache (optimize hit rate L1, miss rate L2)
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Replacement policies
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LRU, LFU, FIFO, rand
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memory management and protection
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permission bits; uses main efficiently(send unneeded to disk)
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Process isolation/memory protection
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own add spaces; can't interfere with another's memory
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loading linking simplified
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Unallocated
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not yet created, no data, no space
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Uncached/cached
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currently cached/not cached
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cache uses PA, since with VA, although can be accessed asap, aliasing, 2 VA may map to same block, would not know which one
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memory utilization (sum of malloc'd data/heap size)
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good performance (malloc/free calls return quick)
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constraints: can't modify malloc'd memory; can't move malloc'd block
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