On Wed, 21 Dec 2022, Segher Boessenkool wrote: > > --- a/gcc/tree.cc > > +++ b/gcc/tree.cc > > @@ -9442,15 +9442,6 @@ build_common_tree_nodes (bool signed_char) > > if (!targetm.floatn_mode (n, extended).exists (&mode)) > > continue; > > int precision = GET_MODE_PRECISION (mode); > > - /* Work around the rs6000 KFmode having precision 113 not > > - 128. */ > > It has precision 126 now fwiw. > > Joseph: what do you think about this patch? Is the workaround it > removes still useful in any way, do we need to do that some other way if > we remove this?
I think it's best for the TYPE_PRECISION, for any type with the binary128 format, to be 128 (not 126). It's necessary that _Float128, _Float64x and long double all have the same TYPE_PRECISION when they have the same (binary128) format, or at least that TYPE_PRECISION for _Float128 >= that for long double >= that for _Float64x, so that the rules in c_common_type apply properly. How the TYPE_PRECISION compares to that of __ibm128, or of long double when that's double-double, is less important. -- Joseph S. Myers jos...@codesourcery.com
