Hi Iain,
on 2024/6/4 14:21, Iain Sandoe wrote:
> Hi Kewen,
>
>> On 3 Jun 2024, at 04:00, Kewen Lin <li...@linux.ibm.com> wrote:
>>
>> Joseph pointed out "floating types should have their mode,
>> not a poorly defined precision value" in the discussion[1],
>> as he and Richi suggested, the existing macros
>> {FLOAT,{,LONG_}DOUBLE}_TYPE_SIZE will be replaced with a
>> hook mode_for_floating_type. To be prepared for that, this
>> patch is to replace use of LONG_DOUBLE_TYPE_SIZE in darwin.c
>> with TYPE_PRECISION of long_double_type_node.
>>
>> [1] https://gcc.gnu.org/pipermail/gcc-patches/2024-May/651209.html
>>
>> gcc/ChangeLog:
>>
>> * config/darwin.cc (darwin_patch_builtins): Use TYPE_PRECISION of
>> long_double_type_node to replace LONG_DOUBLE_TYPE_SIZE.
>> ---
>> gcc/config/darwin.cc | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/gcc/config/darwin.cc b/gcc/config/darwin.cc
>> index 63b8c509405..9129378be37 100644
>> --- a/gcc/config/darwin.cc
>> +++ b/gcc/config/darwin.cc
>> @@ -3620,7 +3620,7 @@ darwin_patch_builtin (enum built_in_function fncode)
>> void
>> darwin_patch_builtins (void)
>> {
>> - if (LONG_DOUBLE_TYPE_SIZE != 128)
>> + if (TYPE_PRECISION (long_double_type_node) != 128)
>> return;
>
> Darwin (at this revision) supports long-double-{64,128}, but the support is
> limited
> to ibm128 for the 128b case.
>
> The purpose of this code is to adjust the libc function name in response to
> the
> {64,128} for the long double type - when that is 128.
>
> It seems that the revised version should be no less fragile than the original
> (since
> we now have potentially two 128b long double formats, although IEEE754 is not
> yet
> implemented for < p7 so should not (yet) be relevant).
Thanks for the information, yes, from what's in build_common_tree_nodes, both
LONG_DOUBLE_TYPE_SIZE and TYPE_PRECISION (long_double_type_node) should be the
same.
>
> So, OK for the Darwin parts.
Pushed as r15-1034, thanks!
BR,
Kewen
> thanks,
> Iain
>
>
>>
>> #define PATCH_BUILTIN(fncode) darwin_patch_builtin (fncode);
>> --
>> 2.43.0
>>
>
