Jakub Jelinek wrote: > On Tue, Aug 23, 2011 at 11:57:58AM +0200, Bernd Schmidt wrote: >> On 08/23/11 11:52, Jakub Jelinek wrote: >>> On Tue, Aug 23, 2011 at 11:35:07AM +0200, Bernd Schmidt wrote: >>>>> cse_process_notes_1 >>>>> perhaps could be changed for VOIDmode new_rtx to try to >>>>> simplify_replace_rtx it... >>>> Is this where the problem came from? Sounds like it's worth a try. >>> In this case, yes. But there are many other places all around the >>> compiler that need to disallow unary op with VOIDmode operand. >>> In cse.c alone e.g. fold_rtx (twice), in combine.c e.g. in do_SUBST, >>> subst, etc. Do we want to special case all those 7 unary ops there too? >>> Is it really worth it to save one subreg or truncate in the md patterns >>> for rarely used rtxes? >> Maybe not. I'll approve a patch to change it back, even if I think it's >> not a good representation. > > We can remove that restriction again once CONST_INTs are no longer VOIDmode. > > Here is an untested patch, will bootstrap/regtest it now on x86_64-linux > and i686-linux, on c6x it should make no difference IMHO (looked like a typo > in the expander which wasn't used anyway), can somebody test it on AVR and
Tested you patch against r177949 on avr-unknown-none for C/C++. There are no regressions and the new test case passes fine. Johann > BFIN? My grepping through *.md didn't find any other places where the > operand wouldn't have the same mode as operation. > > 2011-08-23 Jakub Jelinek <ja...@redhat.com> > > PR middle-end/50161 > * simplify-rtx.c (simplify_const_unary_operation): If > op is CONST_INT, don't look at op_mode, but use instead > mode. > * optabs.c (add_equal_note): For FFS, CLZ, CTZ, > CLRSB, POPCOUNT, PARITY and BSWAP use operand mode for > operation and TRUNCATE/ZERO_EXTEND if needed. > * doc/rtl.texi (ffs, clrsb, clz, ctz, popcount, parity, bswap): > Document that operand mode must be same as operation mode, > or VOIDmode. > * config/avr/avr.md (paritysi2, *parityqihi2.libgcc, > *paritysihi2.libgcc, popcountsi2, *popcountsi2.libgcc, > *popcountqihi2.libgcc, clzsi2, *clzsihi2.libgcc, ctzsi2, > *ctzsihi2.libgcc, ffssi2, *ffssihi2.libgcc): For unary ops > use the mode of operand for the operation and add truncate > or zero_extend around if needed. > * config/c6x/c6x.md (ctzdi2): Likewise. > * config/bfin/bfin.md (clrsbsi2, signbitssi2): Likewise. > > * gcc.dg/pr50161.c: New test.
