rs6000: using pli for constant splitting
For constant building e.g. r120=0x66666666, which does not fit 'li or lis',
'pli' is used to build this constant via 'emit_move_insn'.
While for a complicated constant, e.g. 0x6666666666666666ULL, when using
'rs6000_emit_set_long_const' to split the constant recursively, it fails to
use 'pli' to build the half part constant: 0x66666666.
'rs6000_emit_set_long_const' could be updated to use 'pli' to build half
part of the constant when necessary. For example: 0x6666666666666666ULL,
"pli 3,
1717986918; rldimi 3,3,32,0" can be used.
gcc/ChangeLog:
* config/rs6000/rs6000.cc (rs6000_emit_set_long_const): Add code to use
pli for 34bit constant.
gcc/testsuite/ChangeLog:
* gcc.target/powerpc/const-build-1.c: New test.