Jim, thank you for the fix! The patch looks good to me. Maybe we should also apply this to __atomic_add_fetch_4 and __atomic_add_fetch_8?
Thanks, Cherry On Tue, May 21, 2019 at 11:25 PM Jim Wilson <j...@sifive.com> wrote: > On Sun, May 19, 2019 at 5:22 AM Andreas Schwab <sch...@linux-m68k.org> > wrote: > > ../../../libgo/go/runtime/mbitmap.go: In function > ‘runtime.setMarked.runtime.markBits’: > > ../../../libgo/go/runtime/mbitmap.go:291:9: internal compiler error: > Segmentation fault > > 291 | atomic.Or8(m.bytep, m.mask) > > | ^ > > This is failing for RISC-V because __atomic_or_fetch_1 isn't a > built-in function that can be expanded inline. You have to call the > library function in libatomic. The C front-end is registering all of > the built-in functions, but it looks like the go front-end is only > registering functions it thinks it needs and this list is incomplete. > In expand_builtin, case BUILT_IN_ATOMIC_OR_FETCH_1, the external > library call for this gets set to BUILT_IN_ATOMIC_FETCH_OR_1. Then in > expand_builtin_atomic_fetch_op when we call builtin_decl_explicit > (ext_call) it returns NULL. This is because the go front end > registered BUILT_IN_ATOMIC_OR_FETCH_1 as a built-in, but did not > register BUILT_IN_ATOMIC_FETCH_OR_1 as a built-in. The NULL return > from builtin_decl_explicit gives us an ADDR_EXPR with a NULL operand > which eventually causes the internal compiler error. It looks like > the same thing is done with all of the op_fetch built-ins, so use of > any of them means that the fetch_op built-in also has to be > registered. I verified with a quick hack that I need both > BUILT_IN_ATOMIC_FETCH_OR_1 and BUILT_IN_ATOMIC_FETCH_AND_1 defined as > built-ins to make a RISC-V go build work. I haven't done any testing > yet. > > Jim > > -- > You received this message because you are subscribed to the Google Groups > "gofrontend-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to gofrontend-dev+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/gofrontend-dev/CAFyWVaY8aMmhmnWpoGdywaeEhiXmSUe8qqha%2BHhvbxYHhUnisQ%40mail.gmail.com > . > For more options, visit https://groups.google.com/d/optout. >
