Aurelien Buhrig <aurelien.buhrig.gcc@xxxxxxxxx> writes: > I would like to force accesses to some memory variables in a specific mode. > For example, I would like GCC to access a 16-bit wide hardware > register always in HImode when using a 16bit wide bitfield struct... > Currently, GCC can accesses part of this memory structure using > QImode, which is not always permitted. > Is there a way to do it using an attribute ? Or perhaps another way ? > > If a target specific attribute must be defined, what should it > control, and how to recognized it in my backend ? You should always use a volatile qualified pointer when accessing a hardware register. When you do that, gcc should always use the appropriate mode. Ian
