On Wed, Jul 08, 2020 at 10:32:20AM -0400, Mathieu Desnoyers wrote: > > As far as I can see, %U is mentioned in > > https://gcc.gnu.org/onlinedocs/gcc/Machine-Constraints.html in the > > powerpc subpart, at the "m" constraint. > > Yep, I did notice it, but mistakenly thought it was only needed for "m<>" > operand, > not "m".
Historically, "m" meant what "m<>" does now (in inline asm). Too many people couldn't get it right ever (on other targets -- not that the situation was great for PowerPC, heh), so in inline asm "m" now means "no pre-modify or post-modify". Segher
