Hi! On Mon, Jan 17, 2022 at 09:06:25PM +0100, Sebastian Huber wrote: > On 11/01/2022 09:10, Sebastian Huber wrote: > >On 20/04/2021 17:00, Segher Boessenkool wrote: > >>There are various non-IBM CPUs with isel as well, so it is easiest if we > >>just don't consider that flag here (it is not needed). > >> > >>2021-04-20 Segher Boessenkool<seg...@kernel.crashing.org> > >> > >> PR target/100108 > >> * config/rs6000/rs6000.c (rs6000_machine_from_flags): Do not > >>consider > >> OPTION_MASK_ISEL. > >>--- > >>Committed to trunk and 11. Will do 10 in a week or so. > > > >sorry for the late response, however, I noticed a GCC build issue with > >this patch:
[ big snip ] > >/tmp/ccZJ18fW.s: Assembler messages: > >/tmp/ccZJ18fW.s:24: Error: unrecognized opcode: `isel' > >make: *** [Makefile:501: _negvdi2.o] Error 1 > > > >The assembler is called like this: > > > >/tmp/sh/b-gcc-powerpc-rtems6/./gcc/as -I > >/home/EB/sebastian_h/src/gcc/libgcc/../newlib/libc/sys/rtems/include -I > >. -I . -I ../../../.././gcc -I /home/EB/sebastian_h/src/gcc/libgcc -I > >/home/EB/sebastian_h/src/gcc/libgcc/. -I > >/home/EB/sebastian_h/src/gcc/libgcc/../gcc -I > >/home/EB/sebastian_h/src/gcc/libgcc/../include -a32 -me500 -mbig -o > >_negvdi2.o _negvdi2.s > > > >Using -me500 seems to be all right, however, the file contains a machine > >directive: > > > > .file "libgcc2.c" > > .machine ppc > > .section ".text" > > > >If I remove the ".machine ppc" by hand, the file can be assembled with > >the above command line. > > > >The affect of the patch is: > > > >diff -u _negvdi2.s.before _negvdi2.s.after > >--- _negvdi2.s.before 2022-01-11 09:07:43.313828636 +0100 > >+++ _negvdi2.s.after 2022-01-11 08:54:08.424946502 +0100 > >@@ -1,5 +1,5 @@ > > .file "libgcc2.c" > >- .machine power9 > >+ .machine ppc Which is "correct". rs6000_machine_from_flags should be updated to know about these CPUs: if you have a -mcpu= that outputs instructions that are not .machine ppc (or ppc64), the compiler should emit some appropriate .machine instead. > I can try to fix this, however, for me it is not really clear in which > direction this should be fixed. I can build the GCC 10.3.0 release (it > uses .machine power9). The GCC 10 branch is broken (it uses .machine > ppc). Using the .machine directive and a command line option (-me500) > seems to be a bit inconsistent. It should be one or the other. Exactly. > Would a patch which changes .machine ppc to .machine e500 for -mcpu=8540 > be the right way to fix this issue? Yes :-) Do you have the info needed to make a patch like this for all FSL CPUs? Segher
