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Drew T
3a67dd609f
The largest unmatched core in the game, walled at close=2 for the permuter (25 min, no close) and
queued for a gdb-on-cc1 read. Closed WITHOUT gdb — the RTL dumps were the oracle:
- THE TIE, byte-measured (.lreg): &g.sz1 pseudo 228 refs 13 / live_length 783; &g.sz2 pseudo 230
refs 13 / 782 -> pri = int(390000/L) = 498 == 498, an exact int-truncation tie in global.c:594
allocno_compare. Tie-break = creation order -> allocation follows emission; the target needs them
to DIFFER (allocation sz2-first, emission sz1-first). The shipped operand-permutation workaround
could only pick one (close=2 vs close=10).
- THE FIX (§47): restore NATURAL operand order (emission correct) + ONE zero-byte
`__asm__ volatile ("")` placed BETWEEN two existing GTE volatile asms (no new cse/sched barrier —
one is already there) -> +1 static insn at global-alloc time -> L 784/783 -> pri 497 vs 498 ->
the tie SPLITS toward the shorter-lived (later-created) pseudo, which is ALWAYS the direction
"allocation != creation" requires. All 10 grants cascade; MATCH 952/952 first try; the slider
emits only #APP/#NO_APP (zero bytes). PIN-FREE, ×113 template-safe.
- BANKED ×1 in ov_SC01_000 through the WHOLE-BINARY gate (jr fn — match_one is not the arbiter,
§8a): lazy isolation -> new region ov_SC01_000_jr_8017BEBC + 9-piece jtbl interleave -> splice ->
BYTE-IDENTICAL. One TU-visible decl reconcile en route (D_800B9A02: declare the TU's `short`,
force the unsigned halfword at use `(*(u16*)&D_800B9A02)` — §8d sub-class (b)).
- R22 clean-fleet 136/136 BYTE-IDENTICAL; 0 NON_MATCHING (G4). The ×113 sibling sweep is IMM-class
(scattered addresses) -> Task-8 mechanical work via the imm engine.
- cookbook §47 (the slider method + the placement rule + the direction law); decision-log (R31).