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This is internally consistent.\n\n3. **Distinguishing FACT/ASSUMPTION/PROPOSAL/RECOMMENDATION/OPEN QUESTION**: The document does this throughout, with explicit markers.\n\n4. **Quantitative claims check**:\n   - SRT-4 divider: 2·XLEN/log2(4) = 64/2 = 32 quotient digits — correct.\n   - SRT-8: 2·XLEN/log2(8) ≈ 64/3 ≈ 21.3 — correct.\n   - Newton–Raphson: \"roughly 2 multiplies plus fixup\" — this is questionable. Newton–Raphson for division typically requires: (1) initial reciprocal approximation, (2) one or two Newton–Raphson refinement iterations, (3) multiply by dividend. The standard form is more like 3 multiplies (initial ROM multiply, NR refinement, final multiply), not 2. The document says \"roughly 2–3 multiplies\" earlier in the division section but \"roughly 2 multiplies plus fixup\" in performance considerations. This is a minor inconsistency and arguably understates the cost.\n\n5. **SRT most-negative/−1 corner case**: The document correctly notes this is a property of signed division \"at any radix\" — this is true. The fixup approach described is standard.\n\n6. **Zbkb / carry-less multiply**: The document correctly distinguishes `CLMUL*` from `MULH*` and notes `Zbkb` doesn't specifically use `MULH*`. This is a correction of an earlier draft error, which is good.\n\n7. **`Zfa` reference**: The document correctly notes `Zfa` is a floating-point extension and not appropriate for integer FMA. This is accurate.\n\n8. **128-core scaling**: The shared-pool discussion (option K=8 or 16) is a reasonable design point that earlier surveys often omit. The reasoning about wire delay is sound.\n\n9. **Verification considerations**: The document correctly notes that per-core verification is necessary but not sufficient for system-level concerns. This is a thoughtful correction.\n\n10. **\"Free byproduct\" framing for MUL**: The document correctly notes this doesn't extend cleanly to W-variants.\n\n11. **Self-corrections**: The document explicitly notes corrections to an earlier draft (e.g., RV32 MULH* description, Zbkb conflation, area discussion, verification overstatement). This is honest but somewhat unusual in a research document — it suggests the document is a revision and the \"earlier draft\" is unavailable for review.\n\n12. **One potentially problematic claim**: \"A `DIV` can be replaced by a software Newton–Raphson routine in a few hundred instructions.\" This is presented as fact but is actually an ASSUMPTION/rough estimate. A software Newton–Raphson `divdi3` is typically more than \"a few hundred\" instructions when including the iteration loop, refinement, and final correction — though the magnitude is order-of-magnitude correct. Minor.\n\n13. **\"Local replication, while more silicon, is the conventional answer\"** — this is presented as fact but is a generalization. It's true for most designs but \"conventional\" is somewhat hand-wavy. Acceptable in context.\n\n14. **The document explicitly states \"INSUFFICIENT EVIDENCE\" for citations and quantitative claims**, and avoids fabricating either. This is the right approach for a stub document.\n\n15. **Recommendations**: They follow logically from the analysis and explicitly mark what's recommendation vs. proposal vs. insufficient evidence.\n\n16. **Missing alternatives check**: The document covers iterative, array, tree, Booth, FMA, SRT radix-2/4/8, Newton–Raphson, Goldschmidt, shared pool, and emulation. This is comprehensive.\n\n17. **One factual nuance**: The document says `MULH*` exists as native instructions in both RV32 and RV64, and that \"the upper 32 bits of the full product are produced directly\" in RV32. This is correct — in RV32, `MULH` produces the upper 32 bits of a 32×32 product; it's not a paired 32-bit emulation. The document correctly identifies that an earlier draft was wrong on this.\n\n18. **\"The SRT most-negative / −1 corner case ... is not specific to radix ≥ 4\"** — correct. It exists for any signed division algorithm.\n\n19. **The recommendation to power-gate MDUs on idle tiles** is marked INSUFFICIENT EVIDENCE for quantification, which is appropriate.\n\n20. **The \"16–20 cycles\" informal claim about SRT-8** is correctly noted as not accounting for fixup cycles and not cited.\n\n**Overall assessment**: The document is honest about its limitations, explicitly marks assumptions and uncertainties, self-corrects earlier errors, and provides a reasonable survey of the design space. The technical content is accurate to my knowledge. The Newton–Raphson \"2 multiplies\" claim is mildly off (more like 3), and the \"few hundred instructions\" for software emulation is rough, but both are presented in qualitative context. The document is a stub and explicitly says so.\n\nThe self-corrections referencing \"the earlier draft\" and \"the original draft\" are unusual — they suggest this is a revision, but no original is provided. This isn't a technical error but a documentation hygiene issue. It doesn't rise to a FAIL.\n\nVERDICT: PASS\n\nISSUES:\n- Minor quantitative imprecision: Newton–Raphson division latency is described as \"roughly 2 multiplies plus fixup\" in Performance Considerations, while earlier in the document the division section says \"Latency roughly 2–3 multiplies, with small additional control.\" Standard Newton–Raphson division is typically three multiplies (initial reciprocal approximation, one or two NR refinement iterations, final multiply by dividend). The \"2 multiplies\" figure understates the cost; consistency between the two statements is also missing.\n- Minor imprecision: \"A `DIV` can be replaced by a software Newton–Raphson routine in a few hundred instructions\" is presented as a soft fact; typical software `divdi3` implementations using Newton–Raphson are larger than a few hundred instructions, though order of magnitude is roughly right. Marking as ASSUMPTION would be more accurate.\n- Documentation hygiene: multiple references to \"the earlier draft\" / \"the original draft\" / \"the previous draft\" describing errors and corrections, but the original draft is not provided for review. This is not a technical failure but weakens auditability — a reader cannot verify the corrections.\n- The \"16–20 cycles\" informal figure for SRT-8 is correctly flagged as not citable, but the document's own \"≈ 21–22 quotient digits plus fixup\" implies roughly 22–25+ cycles for a non-overlapped SRT-8. The claim that the informal figure \"does not account for fixup cycles\" is plausible but the document does not provide its own rigorous cycle count for comparison.\n- The \"convention\" claims (e.g., \"SRT is the dominant technique for high-performance scalar cores\"; \"Local replication, while more silicon, is the conventional answer\") are reasonable generalizations but are presented without citation. Acceptable in a stub but should be flagged if the document were to be promoted beyond stub status.\n\nREQUIRED FIXES:\n- None. The document is technically acceptable as a stub with explicit scope limitations, internally consistent, and properly distinguishes FACT / ASSUMPTION / PROPOSAL / RECOMMENDATION / OPEN QUESTION throughout.\n\nCONFIDENCE: HIGH","refusal":null,"reasoning":null}}],"usage":{"prompt_tokens":8663,"completion_tokens":1689,"total_tokens":10352,"cost":0,"is_byok":false,"prompt_tokens_details":{"cached_tokens":353,"cache_write_tokens":0,"audio_tokens":0,"video_tokens":0},"cost_details":{"upstream_inference_cost":0,"upstream_inference_prompt_cost":0,"upstream_inference_completions_cost":0},"completion_tokens_details":{"reasoning_tokens":0,"image_tokens":0,"audio_tokens":0}}}