wave8_transpose_16x2_pipe2()

FASTLED_FORCE_INLINE FL_IRAM FL_OPTIMIZE_FUNCTION void fl::detail::wave8_transpose_16x2_pipe2	(	const Wave8Byte	lane_waves_a[16],
		const Wave8Byte	lane_waves_b[16],
		u8	output_a[16 *sizeof(Wave8Byte)],
		u8	output_b[16 *sizeof(Wave8Byte)] )

Pipe2: transpose 16-lane × 2-byte-positions in one fused call.

Result is bit-identical to two sequential wave8_transpose_16 calls; the win comes from interleaving the two independent OR-trees inside the symbol loop so the in-order RV32 P4 can fill load-use stall cycles from position A with ALU ops from position B (and vice versa). Measured +26% / frame vs sequential calls on P4 v1.3 (#2548).

Definition at line 249 of file wave8.hpp.

                                                                     {
    for (int symbol_idx = 0; symbol_idx < 8; symbol_idx++) {
        u8 la[16];
        u8 lb[16];
        for (int lane = 0; lane < 16; lane++) {
            la[lane] = lane_waves_a[lane].symbols[symbol_idx].data;
            lb[lane] = lane_waves_b[lane].symbols[symbol_idx].data;
        }
        spread_transpose16_symbol(la, output_a + symbol_idx * 16);
        spread_transpose16_symbol(lb, output_b + symbol_idx * 16);
    }
}

References spread_transpose16_symbol().

Referenced by fl::wave8Transpose_16x2_pipe2().

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