https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116909
--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> --- https://gcc.gnu.org/onlinedocs/gcc-14.2.0/gcc/Simple-Constraints.html Documents the r constraints. https://gcc.gnu.org/onlinedocs/gcc-14.2.0/gcc/Extended-Asm.html#OutputOperands Documents the `+`.
