rajamesandClaude Opus 5.5
638aeb6636
C! as written in 5.3 called RSHIFT and LSHIFT (which call SWAP) and OR. It is now one straight-line case per byte position: the byte is shifted up with a `2* unext` loop, that byte of the cell cleared with a constant mask, and the two added. The word address is `2/ 2/` of the byte address. The upper half of a 64-bit cell is still preserved. Headroom (data cells under args / return entries): 5/4 -> 7/7. Same checks as before (every byte of two adjacent words, eight values, neighbours and the upper half untouched) at 32- and 64-bit cells, optimised and ASan+UBSan (`make test`, `make sanitize`). Four mutations fail, one of them only at 64-bit cells, where it differs. test_pictured.c carries the same C!. The pictured words did not gain return-stack room from this: <# #S #> still leaves 2 entries and the signed picture 1. With C! shallow, the deepest point is now inside `#`, which holds the high quotient on the return stack across its second UM/MOD. Recorded in 5.8; `#` is unchanged. Test results on the amd64 host only. This is a development check, not acceptance (JUSTIFICATION.md section 16). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
v4/
StarForth v4: the 32-instruction F18-derived core. The design lives in
docs/v4.0.0/JUSTIFICATION.md (why) and docs/v4.0.0/DECOMPOSITION.md
(every v3 word mapped to a v4 fate).
The first deliverable is the hosted C99 golden model (JUSTIFICATION.md §10,
step 1). It must pass POST and hold K≡1.0 with 32- and 64-bit cells on all
three host ISAs.
Acceptance (JUSTIFICATION.md §16): v4 must be equivalent to v3 at any point
in time, with the same vocabularies and behaviour, on the F18-derived engine;
and every ISA, hosted and bare metal, must still reach its ok prompt.
make -C v4 test passing is a development check, not acceptance.
What exists so far is the single node: registers, circular stacks, memory, all
32 opcodes, and per-opcode and per-call-target heat. make -C v4 test builds
and runs the tests at both cell widths; make -C v4 sanitize repeats them
under ASan and UBSan. There is no compiler capsule, no POST and no K
measurement yet.