- boundary/bounce_back.cuh: apply_wall_bb_d2q9_rows(y, top_row, ...) is
the existing half-way y-wall correction with an explicit top row;
apply_wall_bb_d2q9_y_pull keeps its signature and calls it with NY - 2.
bounce_back_swap_d2q9(f) names the full opposite-pair swap.
- streaming/pull_double_buffer.cuh: load_node(fi, n, f) loads one node's
stored populations.
- step/block_channel.cu uses all three instead of its inline copies: the
wall swap, the outlet donor gather, and rows 1 / ny-2 (now one call with
the physical top row; same y == 1 / y == top_row order and loads).
Same statements, branch order, indices and arithmetic.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
