I am about the business of seeing what I can find for you on this song and its history. I can tell you that it is indeed still sung in Ireland and with the 200th anniversary of the Rising of 1798 just past it has had something of a revival. The tune was also appropriated for a song about a latter day rebel, Joe MacDonald.

Just as a bit of extra for you, here is are the lyrics to a version of it in Irish. There may be some spelling errors in there, but I think it is correct, for the most part.

Ce/ hiad na sluaite fear is ban
Ag gluiseacht fan na sli/
Siad fir is mna/ o/ chnoc's gleann
'S o/ bhruacha Bhanna Bui
Ta/ faghairt 'na rosc 's feidhm 'na gcos'
Ta/id mall, ro/mhall, monuar
Mar ta/ Rodi Mac Corlai/ ag dul don chroch
Ar Dhroichead Tuam' innui.

Ani/os an tsra/id 's cheann go hard
A ghabh an sa/rfhear groi/
'S ro/p' a chrocht' ta/ fillte docht
Faoi chuacha o/rg' a chinn
Ni/l deoir na/ ne/al'na shu/ile gle/
Ta/id lonrach, gle/ineach, ciu/in
Agus Rodi Mac Corlai/ ag dul don chroch
Ar Dhroichead Tuam' innui

Dob i/ sin sra/id a ghabh se/ la/
'S pic 'na la/imh go dian
'Na dhiaidh aniar bhi/ bui/on fear fi/or
'S do/ chas ard 'na gcroi/
Go hAontraim ghluais an bhui/on go buach
Dob eisean ceann an tslua
Ach ta/ Rodi Mac Corlai/ ag dul don chroch Ar Dhroichead Tuam' inniu.
^^