Defragmented and efficient micro-operation cache
A processor includes a processor core and a micro-op cache communicably coupled to the processor core. The micro-op cache includes a micro-op tag array, wherein tag array entries in the micro-op tag array are indexed according to set and way of set-associative cache, and a micro-op data array to store multiple micro-ops. The data array entries in the micro-op data array are indexed according to bank number of a plurality of cache banks and to a set within one cache bank of the plurality of cache banks.
1. A processor comprising:
a processor core circuitry; and
a micro-op cache communicably coupled to the processor core circuitry, the micro-op cache comprising:
a micro-op tag array, wherein tag array entries in the micro-op tag array are indexed according to set and way of set-associative cache; and
a micro-op data array to store multiple micro-ops, wherein data array entries in the micro-op data array are indexed according to bank number of a plurality of physical cache banks and to a set within one physical cache bank of the plurality of physical cache banks, and wherein allocation to the micro-op data array is according to sequential bank numbers of the plurality of physical cache banks.
2. The processor of claim 1 , wherein a next sequential bank number after a last cache bank of the plurality of physical cache banks comprises a first bank number associated with a first cache bank of the plurality of physical cache banks.
3. The processor of claim 2 , further comprising a cache controller coupled to the micro-op cache, the cache controller to:
store, in a register of the processor, identification of a final cache bank of the plurality of physical cache banks to which a final micro-op of a first entry was allocated in the micro-op data array; and
allocate, to a next cache bank that sequentially follows the final cache bank of the plurality of physical cache banks, a first micro-op of a second entry to the micro-op data array, wherein allocation of the second entry sequentially follows allocation of the first entry.
4. The processor of claim 2 , wherein allocation to the micro-op data array is to begin allocation to a physical cache bank of the plurality of physical cache banks other than a first physical cache bank of the plurality of physical cache banks in at least some cache entry allocations.
5. The processor of claim 1 , wherein the micro-op tag array comprises a plurality of index pointers, each index pointer of the plurality of index pointers to point to a bank number and set within a physical cache bank of the plurality of physical cache banks of the micro-op data array.
6. The processor of claim 5 , wherein each physical cache bank of the plurality of physical cache banks of the micro-op data array is partitioned into a plurality of regions, each region spanning multiple consecutively-numbered sets, and wherein each index pointer of the plurality of index pointers is to point to a set within an identified region of the plurality of regions.
7. The processor of claim 1 , wherein the micro-op data array is sized to be at least thirty percent smaller than the micro-op tag array.
8. An integrated circuit comprising:
a micro-op cache comprising a micro-op tag array and a micro-op data array; and
a cache controller coupled to the micro-op cache, wherein to allocate a first entry to the micro-op cache, the cache controller is to:
allocate indexing metadata of the first entry to the micro-op tag array according to a plurality of sets of ways of set-associative cache; and
allocate a plurality of micro-ops to the micro-op data array according to an index within the micro-op data array, the index comprising bank number of a plurality of physical cache banks and a set within one physical cache bank of the plurality of physical cache banks of the micro-op data array, wherein allocation to the micro-op data array is according to sequential bank numbers of the plurality of physical cache banks.
9. The integrated circuit of claim 8 , wherein a sequential bank number after a last cache bank of the plurality of physical cache banks comprises a first bank number of a first cache bank of the plurality of physical cache banks.
10. The integrated circuit of claim 9 , wherein, upon further allocation to the micro-op cache after a period of micro-op cache hits, the cache controller is further to:
store, in a register, identification of a final cache bank of the plurality of physical cache banks associated with a final micro-op of a most-recent-hit entry in the micro-op data array; and
allocate, to a next cache bank that sequentially follows the final cache bank of the plurality of physical cache banks, a first micro-op of a second entry to the micro-op data array, wherein allocation of the second entry sequentially follows the final cache bank identified in the register.
11. The integrated circuit of claim 8 , wherein, to allocate the plurality of micro-ops to the micro-op data array, the cache controller is to begin allocation to a physical cache bank of the plurality of physical cache banks other than a first physical cache bank of the plurality of physical cache banks.
12. The integrated circuit of claim 8 , wherein the micro-op tag array comprises a plurality of index pointers, each index pointer of the plurality of index pointers to point to a bank number and set within a cache bank of the plurality of physical cache banks of the micro-op data array.
13. The integrated circuit of claim 12 , wherein each physical cache bank of the plurality of physical cache banks of the micro-op data array is partitioned into a plurality of regions, each region spanning multiple consecutively-numbered sets, and wherein each index pointer of the plurality of index pointers is to point to a set within an identified region of the plurality of regions.
14. The integrated circuit of claim 8 , wherein the micro-op data array is sized to be at least thirty percent smaller than the micro-op tag array.
15. A method comprising:
allocating, by a cache controller of a processor, indexing metadata of a first entry to a micro-op tag array of a micro-op cache according to a plurality of sets of ways of set-associative cache; and
allocating, by the cache controller, a plurality of micro-ops of the first entry to a micro-op data array of the micro-op cache, wherein allocating the plurality of micro-ops is according to an index comprising bank number of a plurality of physical cache banks and a set within one physical cache bank of the plurality of physical cache banks of the micro-op data array, and
wherein allocating the plurality of micro-ops to the micro-op data array comprises sequentially allocating each micro-op of the plurality of micro-ops across the plurality of physical cache banks according to a sequential bank number.
16. The method of claim 15 , wherein the sequential bank number after a last cache bank of the plurality of physical cache banks comprises a first bank number of a first physical cache bank of the plurality of physical cache banks.
17. The method of claim 16 , further comprising:
storing, in a register, identification of a final cache bank of the plurality of physical cache banks of the micro-op data array to which a final micro-op of the first entry was allocated; and
allocating, to a next cache bank that sequentially follows the final cache bank of the plurality of physical cache banks, a first micro-op of a second entry to the micro-op data array, wherein allocating the second entry sequentially follows allocating the first entry.
18. The method of claim 15 , wherein allocating the plurality of micro-ops to the micro-op data array comprises beginning allocation to a physical cache bank of the plurality of physical cache banks other than a first physical cache bank of the plurality of physical cache banks.
19. The method of claim 15 , wherein allocating the indexing metadata to the micro-op tag array comprises storing an index pointer for each of a plurality of micro-ops, the index pointer to point to a bank number and set within a physical cache bank of the plurality of physical cache banks of the micro-op data array.
20. The method of claim 19 , further comprising:
partitioning each physical cache bank of the plurality of physical cache banks into a plurality of regions, each region spanning multiple consecutively-numbered sets; and
configuring each index pointer to point to a set within an identified region of the plurality of regions.