On 2/12/19 3:03 AM, David Hildenbrand wrote: > We already forward the 3 bits correctly in the translation functions. We > also have to handle them properly and check for specification > exceptions. > > Setting an invalid rounding mode (BFP only, all DFP rounding modes) > results in a specification exception. Setting unassigned bits in the > fpc, results in a specification exception. > > This fixes LOAD FPC (AND SIGNAL), SET FPC (AND SIGNAL). Also for, > SET BFP ROUNDING MODE, 3-bit rounding mode is now explicitly checked. > > Notes: > 1. Use "float_round_to_zero" for now to handle "Round to prepare for > shorter precision". Looking at the PoP "Summary of Rounding and Range > Actions" for BFP. They differ when it comes to tiny values. > 2. TCG_CALL_NO_WG is required for sfpc handler, as we now inject > exceptions. > > We won't be modeling abscence of the "floating-point extension facility" > for now, not necessary as most take the facility for granted without > checking. > > z14 PoP, 9-23, "LOAD FPC" > When the floating-point extension facility is > installed, bits 29-31 of the second operand must > specify a valid BFP rounding mode and bits 6-7, > 14-15, 24, and 28 must be zero; otherwise, a > specification exception is recognized.
Reviewed-by: Richard Henderson <richard.hender...@linaro.org> > + /* > + * FIXME: we actually want something like round_to_odd, but that does not > + * support all data types yet. > + */ > + float_round_to_zero, Yes, you want round_to_odd. I suppose that's not valid for float128 right now? r~
