In the early days PUSH and POP for the small hardware stack was built around just storing addresses only. But it also saved and optionally restored the C and Z condition code flags.
About a year back, I think, that was changed to PUSHing an ordinary full 32 bits - no flag bits. And POP restores 32 bits, but with optionally the top two bits still replacing C and Z. It seems to be something of a leftover. I have my doubts as to whether anyone even wants that as a feature. Is condition flag setting via this method in use?
I'd like to have POP set the Z flag to indicate the popped value as being zero or not. EDIT: Looking at POPA/B instructions. Make it the same as those would be perfect.
"We suspect that ALMA will allow us to observe this rare form of CO in many other discs.
By doing that, we can more accurately measure their mass, and determine whether
scientists have systematically been underestimating how much matter they contain."