[Bug rtl-optimization/71496] Two picbase loads created for libjava code on powerpc-darwin after rev 228022.

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71496

--- Comment #3 from Iain Sandoe <iains at gcc dot gnu.org> ---
Created attachment 38686
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=38686&action=edit
Proposed fix

Thanks to Segher for helping discuss this through and analysis of the rtl
dumps.

The load_macho_picbase_ insns are not validly copyable; whilst we discussed
that there could be other approaches that would allow multiple blocks to share
one setup block, this is not applicable to the current scenario.

So at 228366, an md attribute was introduced to allow insns to be declared
'non-copyable'.  The patch applies this attribute to the darwin picbase load
and re-load insns; Java bootstrap succeed at 228366; now checking against
current trunk.