noun: migrate lagoon jet to stateless SoftBLAS (64-bit)#1022
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Bump ext/softblas to urbit/SoftBLAS 40ff4fa (allocation-free; per-call
rndMode arg replacing the global softblas_roundingMode; B1-B5 fixes) and
drop the deleted src/softblas_state.c from the wrapper.
Update the lagoon jet for the new API: thread the active rounding mode
through all 32 BLAS calls via a file-static _la_rnd, and rename the local
_set_rounding -> _set_rounding_la to avoid colliding with softblas.h's new
inline. Preserves the 64-bit calling convention (braced u3r_mean
{sample,&ptr} pairs) and syz_x+1 byte handling.
Built on ml/64 with zig 0.15.2; booted fake ~tex and the full lagoon test
suite passes (9 suites, ok=%.y). Jet source matches numerics
lagoon/vere64.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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LGTM, will wait for #1021 before merging this one. |
The %mod ray-op (u3qi_la_mod_i754) and mod-scalar (u3qi_la_mods_i754) jets rounded the quotient to nearest (IEEE remainder) and returned the dividend on a zero divisor, diverging from the Hoon +mod, which does C fmod: truncate the quotient toward zero, and returns NaN on a zero divisor or non-finite operand. Truncate the quotient with softfloat_round_minMag, and when the quotient is non-finite (exp bits all 1) overwrite the result with the width's qNaN. Applied to both functions, all four widths (f16/f32/f64/f128). Verified on ~tex (64-bit jet): 5 mod 3 -> 2.0 (was -1.0); 5 mod 0 -> NaN (was 5.0); for f32 and f64, ray-mod and mod-scalar. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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The %mod ray-op (u3qi_la_mod_i754) and mod-scalar (u3qi_la_mods_i754) jets rounded the quotient to nearest (IEEE remainder) and returned the dividend on a zero divisor, diverging from the Hoon +mod (C fmod: truncate toward zero; NaN on /0 or a non-finite operand). Truncate the quotient with softfloat_round_minMag, and on a non-finite quotient overwrite the result with the width's qNaN. Both functions, all four widths. The 64-bit variant of this fix (PR #1022) was verified on a live ship. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
u3qeq_sub hardcoded u3i_words(4, e.c) where every other f128 op uses the width constant n. On the 64-bit build c3_w is uint64_t, so a float128 is n=2 words; writing 4 emitted a ~256-bit atom whose high half is stack garbage read past the alloca(16) buffer (the observed 254-bit [operand|difference] result). On 32-bit builds n=4, so the literal was accidentally correct -- which is why only the 64-bit (vere64) build mis-evaluated ~(sub rq ...). Verified on a fresh ~lex booted with the rebuilt 64-bit binary: (met 0 (sub:rq .~~~1.0 .~~~0.877)) now 126 bits (was 254), value .~~~0.123..., matching add/mul and the SoftFloat reference. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Summary
Migrates the 64-bit lagoon jet to the current SoftBLAS API, on top of
ml/64.ext/softblasto40ff4fa— allocation-free / stateless rewrite (per-callrndModereplacing the globalsoftblas_roundingMode; B1–B5 correctness fixes). Drop the deletedsrc/softblas_state.cfrom the wrapper.pkg/noun/jets/i/lagoon.cfor the new API: thread the active rounding mode through all 32 BLAS calls via a file-static_la_rnd, and rename the local_set_rounding→_set_rounding_la(avoids colliding withsoftblas.h's new inline). Preserves the 64-bit calling convention — the bracedu3r_mean {sample, &ptr}pairs andsyz_x+1byte handling.The jet also picks up the recent numerics correctness fixes the 64-bit copy was missing (mod round-the-quotient,
_get_dimsleak, range/bloq guards, argmin/argmax index). Source tracks numericslagoon/vere64; see urbit/numerics#37.Testing
Built on
ml/64with zig 0.15.2. Booted a fake~tex, verifiedadd/dot/mmul/modproduce correct values, and the full lagoon test suite passes — all 9 suites,ok=%.y.🤖 Generated with Claude Code