On Wed, 2009-05-06 at 12:03 -0400, Joern Rennecke wrote: > Michael Matz wrote: > >> The easiest solution would be to just make a note that you need the > >> PIC register and then, when expanding the prologue emit the > >> necessary instructions. IMO that makes sense as PIC register setup > >> usually is something the prologue does, like all the other register > >> setups necessary. > > Richard Earnshaw: > > That won't work because the PIC register on ARM is a pseudo, so > > generating it during prologue generation is too late. It needs to exist > > before data flow analysis starts on the RTL. > > How about emitting a set at each place the PIC register is needed, > and making sure that gcse will will common these sets where > appropriate?
I'd rather not. -O0 code is bad enough already; and this just makes more work for the compiler. R.
