TMS320F28377D: PIE nested interrupt enable

Well, the programmer needs to know the PIE group before he can configure, enable, and then service the interrupt.

Otherwise, what you can do is to read the PIECTRL register.  The LSB is an enable, all higher bits capture the PIE vector address of the last interrupt taken.  PIE vectors are 32-bits, so all on even word addresses, hence you don't need the LSB.  From the vector address you could work out the group (see the PIE channel mapping table in the user's guide).

Regards,

Richard