RISC-V Design · All levels

Forwarding Network and Stall Control for Data Hazards: Software and Programmer View

Software and Programmer View for Forwarding Network and Stall Control for Data Hazards.

Software and programmer view

Software and Programmer View for Forwarding Network and Stall Control for Data Hazards is anchored on RAW hazard coverage percentage with zero incorrect-commit events and minimum load-use stall cycles per kilo-instruction.. Convert observations into mechanism-backed decisions with explicit ownership.

  • Keep ISA profile, ABI, and extension assumptions explicit.

  • Validate runtime feature detection against hardware contract.

  • Correlate compiler output with microarchitectural counters.

  • Preserve deterministic trap and privilege behavior in all modes.

Decode contract

diagram
DECODE CONTROL MAP - Forwarding Network and Stall Control for Data Hazards

opcode/funct3/funct7      controls asserted
-----------------------   ---------------------------------------
LUI / AUIPC               rd_write, imm_select(U), alu_add_pc
JAL / JALR                rd_write, pc_redirect, link_write
BRANCH                    cmp_enable, branch_type, pc_redirect
LOAD                      mem_read, rd_write, wb_sel(memory)
STORE                     mem_write, store_size, addr_calc
OP-IMM                    alu_enable, imm_select(I), rd_write
OP                        alu_enable, src2_reg, rd_write
SYSTEM / CSR              csr_readwrite, trap_check, privilege_gate
VECTOR (V extension)      vdecode, lane_mask, vtype_update