Robert, thanks for sharing. That is really useful information!
Kind regards, Abe Kornelis ========== Op 07/06/2024 om 23:59 schreef Ngan, Robert (DXC Luxoft): > FYI: > > A while back, I needed to test if a vector register contained all zeroes, but > could not figure out how without loading another register via VZERO and then > using VCEQGS but I didn't like that since it is really comparing two 64-bit > elements. > Finally, I found I could use VTM against another register loaded via VONE, > and test for CC=0. > Today I realized I can just issue a VTM with the same register as source and > mask, and check for CC=0. No extra register required. > > Testing vector registers is hard, since most vector instructions do not set > condition codes (including the [non decimal] arithmetic and bitwise > operations). > > Robert Ngan > DXC Luxoft
