Function emit_systolic_os_bist_wrapper 

pub fn emit_systolic_os_bist_wrapper(core: &str, r: usize, c: usize) -> String

The self-test wrapper an output-stationary tile core is signed off in: the LFSR drives the r west activation and c north weight lanes, and the r × c stationary accumulators fold into the MISR through registers, row by row. Each row’s accumulators fold into a row word, the row words into two half-folds (foldA, foldB), and the MISR XORs those. The fold stays off the critical path, so the block’s critical path is the array’s PE, and no register reads more than one row’s accumulators, so no fold gathers every accumulator at one point of the die.