conformance: promote gf128 selfconsistent -> strict SW-bitexact (72/3/8)#1377
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gf128 (GoldenFloat128: S1 E49 M78, BIAS=281474976710655=2^48-1, storage u128) promoted from bitexact_selfconsistent to strict bitexact. M=78 > 52 -> no FP lowering, every finite value is an EXACT dyadic odd*2^k (parametric separation- bound lemma, same as gf96). Three witnesses (all abs_error=0): 1. independent dyadic normalizer (gf_wide_independent_witness.py, parametric) 15/15; 2. golden Fraction oracle (conformance/witness/gf128/gf128_decode_ref.py) 15/15; 3. analytic separation-bound (SEPARATION_BOUND.md, zero rounding over 2^128). Cross-check dyadic==Fraction: 201512 representative codes (seed=128) agree. OOM-safe: +-2^48 exponent kept symbolic, numerators <= ~2^80. INDEX: bitexact 71->72, selfconsistent 4->3, structural 8 (sum=83). Status [verified SW] -- NOT on-silicon Tier-E (HW decode/compute [REQUIRES USER ACTION], trinity-fpga #199). Catalog = 83. Closes #1370
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This was referenced Jul 6, 2026
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Promote gf128 (GoldenFloat128: S1 E49 M78, BIAS=2^48-1, u128) selfconsistent -> strict bitexact. M=78>52 -> no FP lowering; every finite value is exact dyadic odd*2^k (parametric separation-bound, same lemma as gf96).
Witnesses (all abs_error=0):
Cross-check dyadic==Fraction: 201512 representative codes (seed=128) agree. OOM-safe (+-2^48 exponent symbolic, numerators <= ~2^80).
INDEX: bitexact 71->72, selfconsistent 4->3, structural 8 (sum=83). E/M/BIAS verified against SSOT specs/numeric/formats_catalog.t27 (e=round(127/phi^2)=49, corrects v1.1 typo e=48).
Status [verified SW] — NOT on-silicon Tier-E (HW [REQUIRES USER ACTION], trinity-fpga #199). Catalog=83.
Closes #1370.