On Fri, May 22, 2015 at 11:48:42AM +0930, Alan Modra wrote: > > I think we should add to > > the canonicalisation rules so that fixed regs sort after other regs. > > That requires a lot of testing. > > What if you have two hard regs as above? Which of reg 5 and reg 76 > sorts first? If they are sorted by register number, then ca appears > in the wrong place. Reverse sorting hard regs might work for this > pattern on powerpc, but that seems an odd choice. And if you say hard > regs ought to keep their original order in rtl like the above, then it > is no more difficult to keep all regs in their original order
I said fixed registers, not hard registers. Very different thing :-) You will not normally see more than one fixed register in a pattern, and it is always somewhat special. Segher
