When a mixed ether containing an aryl and alkyl group is cleaved by HI, the alkyl side leaves as the alkyl iodide and the aryl side stays as the phenol — because the C–O bond to the $s{p}^2$ aromatic carbon is much stronger than the bond to the $s{p}^3$ carbon.

Here benzyl phenyl ether cleaves to give benzyl iodide (${\text{C}}_6{\text{H}}_5{\text{CH}}_2\text{I}$) and phenol (${\text{C}}_6{\text{H}}_5\text{OH}$).