I've found this in the docs, reg-stack.c comments seems like this is what I'm looking for, RTL needs registers some way and the output is just a distance from the top of the stack. Hope this will know push/pop implicitly https://gcc.gnu.org/onlinedocs/gccint/Stack-Registers.html#Stack-Registers
2017-11-15 17:03 GMT+01:00 Ábrahám Endre <abrahamend...@gmail.com>: > So I set up fake registers in target.h, and implement their behaviour with > a stack logic? > My binutils is already ported, how will this work with GAS not knowing > whether i use registers or not? > > 2017-11-15 16:38 GMT+01:00 Jeff Law <l...@redhat.com>: > >> On 11/15/2017 08:33 AM, Ábrahám Endre wrote: >> > Hi, >> > I'm trying to make a gcc backend for a stack machine, is there a way to >> > disable register specific behaviour required by target.h, target.c? also >> > all preserved names in the RTL language assume usages of operands (addm3 >> > mulm3 etc) which is not an option in my target, do I have to manually >> set >> > up new stack-based behaviour in the def? >> I suspect the best way to go is to pretend you have a normal register >> file up through the register allocator. After register allocation >> you'll want to convert to a stacked file. >> >> GCC already does this for the x87 floating point unit, so you could >> probably generalize and build on top of that existing code (reg-stack.c). >> >> jeff >> >> >
