High side gate diode in LT1158 H-bridge example

I was looking for leads on H-bridge design and I noticed a curious thing: in some example circuits for the LT1158 (like the Figure 17. 10A Full Bridge Motor Control at page 20 of the datasheet or Figure 171. H-Bridge Motor Driver with Ground Referenced Current Sensing in AN66) the high side gate driver outputs have clamp diodes toward ground. (D1 and D2 at page 20).  I guess it's only for full bridge DC motor control since other examples don't use these.

What are these diodes for? My first guess is transient protection like the common source under ground transient (coupled through parasitics to the gate), but that is usually solved clamping the source to ground, not the gate. Maybe it's because the DC motor is a highly inductive *and* a generator too?

Is that protection specific to the 1158 topology (since it has no high voltage tub) or it can be applied more generally to other drivers?

I can't find in literature any reference

Thanks in advance