Robert Allan JamesandClaude Sonnet 5
70db955ac9
mixed_math_word_m_slash_mod() had the identical bug class already fixed
in M* (commit 9a09949): it reconstructed the dividend from
`(dhigh << 32) | (dlow & 0xFFFFFFFF)`, the same wrong "32-bit halves of a
64-bit value" assumption. Latent for small inputs (fits in 32 bits, so the
reconstruction coincidentally worked), confirmed genuinely broken for a
true wide double -- feeding M*'s own correct 10^24 output into it gave a
quotient/remainder wrong by many orders of magnitude and the wrong sign.
Unlike M*, this one can't just switch to __int128 -- __int128's own `/`/`%`
need libgcc's __udivti3/__umodti3 for 128-bit division, unavailable in
this freestanding, -nostdlib build (the exact constraint
src/starkernel/arch/amd64/timer.c's own doc comment already flagged:
__int128 multiply/shift-by-constant/compare/subtract all compile clean,
only division doesn't). Fixed instead with a hand-rolled unsigned
128-by-64-bit bit-serial (restoring) long division -- 128 iterations of
shift-by-1/compare/subtract only, all in the safe set. Operates on
magnitudes via unsigned negation from 0 (well-defined even for the
extreme negative edge); signs reapplied afterward matching the same C99
truncating-toward-zero convention the previous, narrower implementation
already used, unchanged.
Verified: rebuilt all three architectures, confirmed clean link with no
__udivti3/__umodti3 undefined-symbol errors. Booted and tested all three,
identical results: 1000000000000 1000000000000 M* SWAP 1000000 M/MOD ->
1000000000000000000 remainder 0 (exact division, the case that was wrong
by orders of magnitude before); three sign-combination cases all correct
(-+, +-, --), confirming sign handling survived the magnitude-only
rewrite. T15 (original small-input case) unaffected. Full 24-case
exerciser reran clean on all three, no regressions.
All bugs found by the std79 exerciser campaign, including this one found
while fixing another, are now closed.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EXieurDfDSsDFdnSyusuWo
src/word_source/
FORTH-79 word implementations, one file per category, registered into the
dictionary via include/word_registry.h. Each .c file here has a
matching header in src/word_source/include/ and (for most categories) a
matching test module in src/test_runner/modules/.
FORTH-79 core
arithmetic_words.c,mixed_arithmetic_words.c—+ - * / MOD ABS MIN MAXand mixed-precision arithmetic.stack_words.c—DUP DROP SWAP ROT OVER NIP TUCK.control_words.c—IF ELSE THEN DO LOOP BEGIN UNTIL WHILE.defining_words.c—: ; CREATE DOES> VARIABLE CONSTANT.memory_words.c—@ ! C@ C! MOVE FILL.return_stack_words.c—>R R> R@ RDROP 2>R 2R@ 2R>.double_words.c—2DUP 2DROP 2SWAP 2@ 2! D+ D-.logical_words.c—AND OR XOR NOT INVERT LSHIFT RSHIFT.io_words.c—EMIT KEY TYPE CR TAB SPACE ACCEPT.string_words.c—S" SLITERALand other string operations.block_words.c—BLOCK BUFFER LOAD THRU FLUSH.format_words.c—.( .R .S HEX DECIMAL BASE.system_words.c—BYE ABORT INCLUDE STATE.dictionary_words.c—FIND SEARCH-WORDLIST WORDS.dictionary_manipulation_words.c— dictionary entry manipulation words.vocabulary_words.c—VOCABULARY DEFINITIONS FORTH-WORDLIST.editor_words.c— block editor words.defer_words.c—DEFER/ISdeferred-word mechanism, used by the Tripod message-dispatch shim (seetools/hermes_tripod_smoke.sh).
StarForth-specific extensions
q48_16_words.c,q48_words.c— Q48.16 fixed-point word bindings.starforth_words.c— StarForth-specific extensions.acl_words.c— word-level ACL system's FORTH-callable primitives (seedocs/03-architecture/word-acl/).lifecycle_words_hosted.c— hosted-build VM lifecycle words (birth/run primitives on the hosted side; kernel-only primitives live insrc/starkernel/capsule/mama_forth_words.c).log_words.c— FORTH-callable logging primitives.inference_words.c— FORTH-callable bindings for the statistical inference engine (Loops #5/#6).physics_benchmark_words.c— benchmark harness for the 7 physics feedback loops.physics_diagnostic_words.c— physics diagnostics (WORD-ENTROPY).physics_freeze_words.c—PHYSICS-FREEZE/PHYSICS-THAW.physics_pipelining_diagnostic_words.c— Loop #4 pipelining diagnostics.dictionary_heat_diagnostic_words.c— Loop #1 heat diagnostics.
See src/word_source/include/ for the matching headers (also includes
mama_forth_words.h, whose .c implementation lives under
src/starkernel/capsule/ since it's kernel-only).