rajamesandClaude Opus 5.5
29cf2688d2
Q.EXP is v3's q48_exp_approx: the Taylor series to 10 terms on |q|, stopping below 50 ulp, 1.0 Q./ e^|q| for q < 0, e^0 = 1.0, and for |q| >= 16.0 either 0 or Q max (v3 returned all ones, which is -ulp read signed under D-8). x, term, sum, sign and term index live in a new 8-cell variable (QE). Checked bit for bit against v3's q48_exp_approx (ported into the test) on 23 edge values and 3000 pseudo-random q in (-16.0, 16.0), at both cell widths, optimised and ASan+UBSan; dropping a term, moving the 50-ulp stop or skipping the reciprocal all fail. Q.EXP calls Q./, which calls (UQ/), which calls D2*C, and at first it left its caller no return entries. Lightened along the chain: - D2*C takes cin in A and builds 2hi+m with `over + +`: no ROT, no SWAP. - (UQ/) parks the quotient bit instead of using ROT, stores q without SWAP, and does its full trial subtraction (with borrow) in line instead of calling DNEGATE D+. - Q.EXP keeps its term index in (QE) instead of a FOR count. Headroom (data under args / return): (UQ/) 4/3 -> 4/4, Q./ 3/2 -> 3/3, Q.EXP 3/2. 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.
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.