[PATCH] D15120: Add support for __float128 type to be used by targets that support it
John McCall via cfe-commits
cfe-commits at lists.llvm.org
Tue Jan 26 12:02:01 PST 2016
rjmccall added a comment.
In http://reviews.llvm.org/D15120#336282, @nemanjai wrote:
> Addressed review comments.
> The key differences are:
> - No assignments or operations between entities of long double and __float128 allowed if the two types have a different representation
> - Each type has a distinct rank
> This isn't the same behaviour as GCC currently has. For example, GCC allows assignments between the two types on PowerPC. The conversion is achieved through a library routine. However, there is no compelling reason at this point to allow such behaviour and this work is deferred until such a need arises.
As I understand it, PPC's long-double (~103 bits of precision) is still strictly less precise than float128_t (113 bits of precision), so it ought to be have lower rank. Is there actually a supported platform where this is not true? If not, we should just add this as another type with higher rank.
More information about the cfe-commits