docs: localize shared-core deep path (GftSadd=54, GftSmul=44) — pipeline the RNE cascade (Refs #1764)

[gHashTag]

Measures where the shared-core critical combinational depth actually is, so the eventual pipeline cut lands in the right place instead of guessing.

• GftSmul is purely combinational (assign result = smul(a,b); the clk/en/ready ports are unused) — so there is no read-before-ready handshake bug.
• Yosys ltp (longest topological path): GftSadd = 54, GftSmul = 44.
• The depth is not the multiplier width: magmul's * lowers to a 32-iteration shift-add, but its operands are 512+mant ∈ [512,1023] (10-bit), so yosys already prunes the dead upper iterations. Hand-narrowing the loop to 10 leaves the depth unchanged (44 → 45) and area flat — a dead end, tested before touching the verified spec (observe-before-mutate).
• The real depth is the dependent normalize/round cascade: magsub's 4-stage priority-shift + <<14 fixed-point + round-to-nearest-even in GftSadd, and magmul's post-product RNE carry in GftSmul.

Concrete pipeline cut (for the Variant-1 work): split each cascade into two registered stages (~27 / ~22 deep), which both halves the path and resynchronises it (killing the placement hazard); the microsequencer then waits a fixed 2-cycle latency instead of a settle counter. The ~47 ns nominal path is already ~100× under the µs settle window, which is why the glitch is a placement hazard a static-timing fix cannot see.

Docs-only; no code or gate changes. Refs #1764

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PR Dashboard

Generated at: 2026-08-07 19:40:41 UTC

• docs: localize shared-core deep path (GftSadd=54, GftSmul=44) — pipeline the RNE cascade (Refs #1764) #1898 docs: localize shared-core deep path (GftSadd=54, GftSmul=44) — pipeline the RNE cascade (Refs #1764) | Created: 2026-08-07 | Updated: 2026-08-07 | 10 failing / 15 total
• chore: civilian mesh positioning — drop drone wording (bpsk.t27) #1874 chore: civilian mesh positioning — drop drone wording (bpsk.t27) | Created: 2026-08-07 | Updated: 2026-08-07 | 2 failing / 25 total
• feat(igla): Wave Loop 897 — module-scope [613][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1858 feat(igla): Wave Loop 897 — module-scope [613][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 896 — module-scope [611][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1856 feat(igla): Wave Loop 896 — module-scope [611][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 895 — module-scope [609][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1854 feat(igla): Wave Loop 895 — module-scope [609][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 894 — module-scope [607][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1852 feat(igla): Wave Loop 894 — module-scope [607][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 893 — module-scope [605][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1850 feat(igla): Wave Loop 893 — module-scope [605][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 892 — module-scope [603][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1847 feat(igla): Wave Loop 892 — module-scope [603][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 1 failing / 3 total
• feat(igla): Wave Loop 891 — module-scope [601][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1844 feat(igla): Wave Loop 891 — module-scope [601][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 0 failing / 4 total
• feat(igla): Wave Loop 890 — module-scope [599][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1842 feat(igla): Wave Loop 890 — module-scope [599][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-07 | Updated: 2026-08-07 | 0 failing / 4 total
• feat(igla): Wave Loop 883 — module-scope [585][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1815 feat(igla): Wave Loop 883 — module-scope [585][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-06 | Updated: 2026-08-06 | 0 failing / 1 total
• feat(igla): Wave Loop 882 — module-scope [583][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1813 feat(igla): Wave Loop 882 — module-scope [583][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-06 | Updated: 2026-08-06 | 0 failing / 12 total
• feat(igla): Wave Loop 881 — module-scope [581][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1810 feat(igla): Wave Loop 881 — module-scope [581][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-06 | Updated: 2026-08-06 | 0 failing / 12 total

Summary

Status	Count
Total Open PRs	13
PRs with Failing Checks	1
PRs with All Checks Green	12
READY	5
FAILING	1
PENDING	0

Seal Status

• ⚠️ STALE -- sha256(compiler.rs)=f74459fc23c3 != manifest seal=87e5cbd3ad94.
  The committed NMSE numbers were certified against an older compiler.rs.
  Run scripts/reseal-check.sh locally for the two-step reseal command (advisory; not a merge gate).

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