Data Memory
The memory region that holds program data, accessed via load and store instructions in the memory stage.
Detailed Explanation
Data memory is where the processor's runtime state lives — the stack, the heap, and any global variables. Load instructions read from it into a register; store instructions write a register value back. The memory stage of the pipeline presents an effective address (usually `rs1 + imm`) plus a byte-enable mask derived from the access width (LB, LH, LW and their unsigned variants), and receives the data one cycle later.
Unlike instruction memory, data memory is read-write, which means it participates in the processor's hazard story. A store followed immediately by a load to the same address must either stall or be forwarded; misaligned accesses may need two memory transactions; and on cached systems, coherence protocols make sure that multiple cores see a consistent view. Even in a minimal single-cycle core, the load/store datapath — byte masking, sign-extending LB/LH, handling word alignment — is one of the trickier parts to get right.