To give just one small practical example, I'm told (by people who are more
familiar with GCC internals than I) that it is not feasible with today's
GCC to port to backends which have a small number of registers.
I think (not sure) that could be attributed to
j...@darrington.wattle.id.au - apologies if I am wrong.
Why?
GCC is doing many optimisations at the GIMPLE level.
Why won't it be possible (even if very painful) to transform GIMPLE to
some architecture with very few registers.
IIRC, the TMS9900 (a microprocessor from texas instruments, in 1976) had
very few hardware registers. One of them being a "pointer" to some
"virtual register bank" on the call stack.
http://www.bitsavers.org/components/ti/TMS9900/TMS_9900_Microprocessor_Data_Manual_May76.pdf
I don't seen any impossibility in generating such instructions from GIMPLE.
Of course, I am not candidate to do so...
Cheers
--
Basile Starynkevitch <bas...@starynkevitch.net>
(only mine opinions / les opinions sont miennes uniquement)
92340 Bourg-la-Reine, France
web page: starynkevitch.net/Basile/
