Hojun-Cho
4fa4bcf34e
B1 (63332fe) landed CQO in both stages' assemblers and switched the
binary `/` and `%` paths to it. The compound-assign sisters (`/=`,
`%=`) were six explicit workarounds across both stages, all calling
out either "fallback for TK_SLASHEQ" or just falling through with no
case at all. With CQO available, every site mechanically ports to the
same "park rhs in CX, slot value into AX, CQO/IDIVQ CX, ferry result
back" sequence.
wwstage cgenexpr.ww:5381-5403 silently no-op'd IDENT-local signed
compound div/mod — `x /= y` and `x %= y` produced no IDIV emit at
all, just a load-bearing `MOVQ BX, off(BP)` that wrote the freshly
loaded slot value back unchanged. Bootstrap byte-id passed because
no selfhost-corpus path exercises signed compound. Latent miscompile
retired alongside the workaround revert.
cstage cgen.c:3735 (top-level-let global compound) was NOT in the
initial five-site bundle and surfaced via worker probing the
wwstage:5147 fix — `let gs: i32 = 100; gs /= 7;` returned 7 (divisor)
on cstage but 14 (correct quotient) on wwstage. Rule 10 caught the
would-be Class A divergence; the sixth site bundles in.
Six sites, one family:
cmd/w6c/cgen.c:3549 deref-compound `*p OP= v`
cmd/w6c/cgen.c:3735 top-level-let `gs OP= v`
cmd/w6c/cgen.c:3765 IDENT-local `x OP= v`
selfhost/cmd/wcc/cgenexpr.ww:3338 deref-compound
selfhost/cmd/wcc/cgenexpr.ww:5147 top-level-let
selfhost/cmd/wcc/cgenexpr.ww:5381 IDENT-local (silent-no-op)
test/wcc/978_intdiv_signed.c adds 7 compound rows × 2 drivers = 14
fixtures (now 68/68): IDENT-local /= /=- /=u, deref *p /= *p %= *p
/=u, with negative-dividend, negative-divisor, and unsigned-high-
bit-set coverage. Top-level-let compound coverage is deferred per
task #18 — single-file inline drivers hit a pre-existing linker
`undefined reference to '<file>.gs'` for LEAQ name(SB) targets.
cstage:3735 and wwstage:5147 are code-review-verified for rule-10
symmetry until #18 lands.
Grep-sweep (`if (n < 0) { neg = true; n = -n; }`) returned two sites
in lib/fmt/fmt.ww i64dec and lib/strconv/strconv.ww — both mirror
ref/hare/strconv/itos.ha's pre-negate idiom for INT64_MIN safety.
Per the Hare-faithful filter, both stay.
245 KiB
245 KiB