This removes output_isel. Instead, the define_insn's now output the
isel instructions directly.
It adds a reg_or_zero operand predicate, too, because the reg_or_cint
predicate is too lax here. Also use it in the "reversed" variants of
the instructions.
* config/rs6000/predicates.md (zero_constant, all_ones_constant):
Move up in file.
(reg_or_cint_operand): Fix comment.
(reg_or_zero_operand): New predicate.
* config/rs6000/rs6000-protos.h (output_isel): Delete.
* config/rs6000/rs6000.c (output_isel): Delete.
* config/rs6000/rs6000.md (isel_signed_<mode>): Use reg_or_zero_operand
instead of reg_or_cint_operand. Output instruction directly (not via
output_isel).
(isel_unsigned_<mode>): Ditto.
(*isel_reversed_signed_<mode>): Use reg_or_zero_operand instead of
gpc_reg_operand. Add an instruction alternative for this. Output
instruction directly.
(*isel_reversed_unsigned_<mode>): Ditto.
From-SVN: r253665
