* Michael Meissner:
> +enum reverse_cond_t {
> + REVERSE_COND_ORDERED_OK,
> + REVERSE_COND_NO_ORDERED
> +};
This should probably be something
like
enum reverse_cond_t {
ordered_ok,
no_ordered,
};
to inhibit implicit conversion to integer types and bool.
(Completely untested.)
> +
> extern enum rtx_code rs6000_reverse_condition (machine_mode,
> - enum rtx_code);
> + enum rtx_code,
> + enum reverse_cond_t);
> extern rtx rs6000_emit_eqne (machine_mode, rtx, rtx, rtx);
> extern rtx rs6000_emit_fp_cror (rtx_code, machine_mode, rtx);
> extern void rs6000_emit_sCOND (machine_mode, rtx[]);
> diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc
> index f9f9a0b931d..c2235d917ad 100644
> --- a/gcc/config/rs6000/rs6000.cc
> +++ b/gcc/config/rs6000/rs6000.cc
> @@ -15360,17 +15360,38 @@ rs6000_print_patchable_function_entry (FILE *file,
> }
>
> enum rtx_code
> -rs6000_reverse_condition (machine_mode mode, enum rtx_code code)
> +rs6000_reverse_condition (machine_mode mode,
> + enum rtx_code code,
> + enum reverse_cond_t ordered_cmp_ok)
> {
> /* Reversal of FP compares takes care -- an ordered compare
> - becomes an unordered compare and vice versa. */
> - if (mode == CCFPmode
> - && (!flag_finite_math_only
> - || code == UNLT || code == UNLE || code == UNGT || code == UNGE
> - || code == UNEQ || code == LTGT))
> - return reverse_condition_maybe_unordered (code);
> - else
> - return reverse_condition (code);
> + becomes an unordered compare and vice versa.
> +
> + However, this is not safe for ordered comparisons (i.e. for isgreater,
> + etc.) starting with the power9 because ifcvt.cc will want to create a
> fp
> + cmove, and the x{s,v}cmp{eq,gt,ge}{dp,qp} instructions will trap if one
> of
> + the arguments is a signalling NaN. */
> +
> + if (mode == CCFPmode)
> + {
> + /* If NaNs are allowed, don't allow the reversal of floating point
> + comparisons when the comparison is used in the context of a floating
> + point conditional move when REVERSE_COND_NO_ORDERED is passed. We do
> + allow the comparsion to be reversed for explicit jumps when
> + REVERSE_COND_ORDERED_OK is passed. */
> + if (!flag_finite_math_only)
> + return (ordered_cmp_ok == REVERSE_COND_NO_ORDERED
That would turn into
ordered_cmp_ok == reverse_cond_t::no_ordered
(Note that identifiers ending in _t are reserved by POSIX.)
