emit_alu3_K
emit_alu3_K(AND, dst, 0xff, tmp, ctx);
emit_alu3_K(SRL, dst, 8, dst, ctx);
emit_alu3_K(AND, dst, 0xff, dst, ctx);
emit_alu3_K(SLL, tmp, 8, tmp, ctx);
emit_alu3_K(SRL, dst, 24, tmp, ctx); /* tmp = dst >> 24 */
emit_alu3_K(SRL, dst, 16, tmp2, ctx); /* tmp2 = dst >> 16 */
emit_alu3_K(AND, tmp2, 0xff, tmp2, ctx);/* tmp2 = tmp2 & 0xff */
emit_alu3_K(SLL, tmp2, 8, tmp2, ctx); /* tmp2 = tmp2 << 8 */
emit_alu3_K(SRL, dst, 8, tmp2, ctx); /* tmp2 = dst >> 8 */
emit_alu3_K(AND, tmp2, 0xff, tmp2, ctx);/* tmp2 = tmp2 & 0xff */
emit_alu3_K(SLL, tmp2, 16, tmp2, ctx); /* tmp2 = tmp2 << 16 */
emit_alu3_K(AND, dst, 0xff, dst, ctx); /* dst = dst & 0xff */
emit_alu3_K(SLL, dst, 24, dst, ctx); /* dst = dst << 24 */
emit_alu3_K(ADD, SP, STACK_BIAS + 128, tmp, ctx);
emit_alu3_K(SLL, bpf_index, 3, tmp, ctx);
emit_alu3_K(SRL, src, 0, dst, ctx);