do_blocks( string $content ): string

2572function do_blocks( $content ) {2573	$blocks                = parse_blocks( $content );2574	$top_level_block_count = count( $blocks );2575	$output                = '';2576 2577	/**2578	 * Parsed blocks consist of a list of top-level blocks. Those top-level2579	 * blocks may themselves contain nested inner blocks. However, every2580	 * top-level block is rendered independently, meaning there are no data2581	 * dependencies between them.2582	 *2583	 * Ideally, therefore, the parser would only need to parse one complete2584	 * top-level block at a time, render it, and move on. Unfortunately, this2585	 * is not possible with {@see \parse_blocks()} because it must parse the2586	 * entire given document at once.2587	 *2588	 * While the current implementation prevents this optimization, it’s still2589	 * possible to reduce the peak memory use when calls to `render_block()`2590	 * on those top-level blocks are memory-heavy (which many of them are).2591	 * By setting each parsed block to `NULL` after rendering it, any memory2592	 * allocated during the render will be freed and reused for the next block.2593	 * Before making this change, that memory was retained and would lead to2594	 * out-of-memory crashes for certain posts that now run with this change.2595	 */2596	for ( $i = 0; $i < $top_level_block_count; $i++ ) {2597		$output      .= render_block( $blocks[ $i ] );2598		$blocks[ $i ] = null;2599	}2600 2601	// If there are blocks in this content, we shouldn't run wpautop() on it later.2602	$priority = has_filter( 'the_content', 'wpautop' );2603	if ( false !== $priority && doing_filter( 'the_content' ) && has_blocks( $content ) ) {2604		remove_filter( 'the_content', 'wpautop', $priority );2605		add_filter( 'the_content', '_restore_wpautop_hook', $priority + 1 );2606	}2607 2608	return $output;2609}
When	Instructions	Calls it makes
`!$i && $priority === false`	19	`parse_blocks(), has_filter()`
`!$i && $priority !== false && !doing_filter()`	23	`parse_blocks(), has_filter(), doing_filter()`
`!$i && $priority !== false && doing_filter() && !has_blocks()`	27	`parse_blocks(), has_filter(), doing_filter(), has_blocks()`
`!$i && $priority !== false && doing_filter() && has_blocks()`	38	`parse_blocks(), has_filter(), doing_filter(), has_blocks(), remove_filter(), add_filter()`