Minecraft wiki entry for execute, associated text: Arguments
<start>: block_pos
<end>: block_pos
Positions of any two diagonal corners of the source volume (the comparand; the volume to compare)
It must be a block position composed of <x>, <y> and <z>, each of which must be an integer or a tilde and caret notation.
<destination>: block_pos
Position of the lower northwest corner of the destination volume (the comparator; the volume to compare to)
Assumed to be of the same size as the source volume
It must be a block position composed of <x>, <y> and <z>, each of which must be an integer or a tilde and caret notation.
<scan mode> : literal (all|masked)
Specifies whether all blocks in the source volume should be compared, or if air blocks should be masked/ignored