I read several articles, and they either use the storage buffer, or replace the storage queue, or are associated with different structures, and I just can not follow. This is what I was thinking of was the store's turn:
- This is the FIFO associative search queue, which stores information about store instructions in a sample order.
- Saves store addresses and data.
- It stores store instruction data until instructions become speculative, i.e. reached the retirement stage. These store instructions are sent to the memory (L1 cache in this case) from the store line only when it reaches the retirement stage. This is important because we do not want the speculative data of the storage to be written into memory, because it would depend on the state of the memory in order, and we would not be able to fix the state of the memory in case of incorrect prediction.
- After an incorrect prediction, the information in the store queue corresponding to the store instructions that were extracted after the incorrect prediction command is deleted.
- Download instructions send a read request to both the L1 cache and the storage queue. If data with the same address is in the queue for storage, it is sent to the download instruction. Otherwise, data obtained from L1 is used.
I'm not sure what a storage buffer is, but I thought it was just a buffer space to store data in legacy storage instructions awaiting write to memory (again, L1).
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