This split is disabled for power7 and up, so we don't often see its
bad effects. However, on a powerpc-linux compiler (which defaults
to PPC750 judging from rs6000/sysv4.h) we see
long double ld1 (void) { return 1.0L; }
compiled with -msoft-float -O2 -S resulting in
ld1:
li 3,0
li 4,0
mr 6,4
mr 5,3
li 4,0
lis 3,0x3ff0
blr
Things go awry in init-regs, with the TFmode reg being initialized to
zero on seeing the subreg from the split. (And that initialization
itself is split by rs6000_emit_move!) Later passes apparently don't
clean up the rubbish.
Since the split was added for Darwin (as the comment says), let's get
rid of it on other targets.
* config/rs6000/rs6000.c (rs6000_emit_move): Disable long
double split for targets other than Darwin.
From-SVN: r266610
