Four byte-verified findings from md_MAIN_003/func_800CF3E8 (467/469 ins), read off
-dS/-dR/-dl/-dr:
1. sched.c true_dependence guards on GET_MODE(mem) != QImode, so a `sb` store aliases
scalar global loads while sh/sw struct stores are exempt - that is what pins the
colour lbu after `sb 0xb` and gives it a mandatory filler slot. A property of the
store's MODE, not of what it points at.
2. An OT-index re-read must be a MEM_IN_STRUCT_P FIXED-address lhu to depend on its
store; expand's memory_address() forces the constant into a reg (la+lhu 0(reg))
unless you copy the whole struct into a 2-byte register local. This was the 468/469
wall for every prior attempt.
3. A `la` above an idx*24 chain needs a single-set base pseudo emitted before the
multiply: block-scope `{ Sprt24 *b_ = ARR; p = &b_[idx]; }`.
4. Recorded as NOT reachable from C: $v1-vs-$a0 for the last prim pointer is
local-alloc's pointer-vs-temp priority tie. Permuter or a §419 density manoeuvre.
Drew T
853cab2a97