--- func_8017FD20 (line 5097) ---
/* The `register ... __asm__("$4")` pin on the FIRST call argument is load-bearing.
 * The target sets $a0 = 0x6FE in the ENTRY block (dbr steals it into the `bnez`
 * delay slot -- sched.md D1 backward fill), but a plain `s32 id = 0x6FE;` local is
 * rematerialised at the use site (single-set constant pseudo -> REG_EQUIV), so the
 * `li` sinks past the label into the join block and dbr fills the slot with the
 * if-body's `lui` instead (SHIFT-DRIFT/+1). Pinning the local to $a0 makes the `li`
 * a hard-reg set that stays where it is written, and the call's arg move degenerates
 * to a deleted `(set (reg 4) (reg 4))`. */
--- every @class/@stuck/@crack note in this translation unit ---
// @class: schedule
// @stuck: none — MATCH (102 ins). MATRIX(0x20:m@0,t@0x14)+SVECTOR in/out stack layout; the only
// @class: straight-derive
// @stuck: none — MATCH (52 ins) on iteration 1, confirmed by rtu_match.
// @class: structural (head-copy eqv takeover -> MATCH); sig widened to the ov_SC03_013
// @class: structural (STRENGTH/mflo!=lw -> MATCH)
// @stuck: none - MATCH (41 ins), match_one + rtu_match.
// @class: regalloc (WIDTH/li!=addu -> MATCH)
// @stuck: none — MATCH (58 ins), match_one + rtu_match. PIN-FREE (no register __asm__).
