On Mon, Apr 30, 2012 at 3:34 PM, Uros Bizjak <ubiz...@gmail.com> wrote: > On Mon, Apr 30, 2012 at 3:10 PM, Jakub Jelinek <ja...@redhat.com> wrote: >> On Mon, Apr 30, 2012 at 02:54:05PM +0200, Uros Bizjak wrote: >>> > My recent changes to zero_extend expanders should handle this >>> > automatically, and will undo generation of zero_extend pattern. Please >>> > see zero_extend<mode>si2_and expander, and how it handles >>> > TARGET_ZERO_EXTEND_WITH_AND targets. >>> >>> Attached patch implements this idea. In addition, it fixes the >>> splitter to not change output mode of zero_extension from HImode and >>> QImode from DImode to SImode. Although they generate the same >>> instruction, I think we should better keep original mode here. >> >> Thanks. I was trying this morning slightly different patch for the same, >> but strangely it failed bootstrap, and didn't get around to analysing >> why a mem store had (zero_extend (subreg (reg))) on a RHS. > > Maybe it was due to slightly wrong splitter? I was changing both, the > expander and the splitter in parallel, and didn't see any failure you > mentioned...
In fact, the problem was already in your original patch. There was a check for REG_P (operands[1]), but it should check for REG_P (operands[0]). There is no zero_extended store, only load. Uros.
