On Thu, Nov 12, 2020 at 11:27 PM Kito Cheng <kito.ch...@sifive.com> wrote:
> Current GCC implementation is RISC-V ISA 2.2, this patch set implement > v20190608 and v20191213, and also add option > -misa-spec=[2.2|20190608|20191213] to change the default ISA spec version. > > There is one major incompatible > > That option will effect the default version of each sub-extension, for > example I-extension is 2.0 for 2.2 and 2.1 for v20190608 and v20191213. > > We also update the -march parser to fit the latest standard, the canonical > ordering for multi-letter, drop version support for G extension, and we > also omitted the version for unrecognized extension. > > And we add an special rule for G extension, imafd can't appear again if G > extension is present, but zicsr and zifencei can. > > The default ISA spec will keep on 2.2, and change that in next GCC release. > This patch series looks OK to me with minor fixes for the things I pointed out. I assume Nelson Chu will look at adding the missing zifencei binutils support? Maybe we should add an attribute for the isa-spec? This is redundant with the arch spec, but might be easier for some folk to handle. Just one version number instead of 6 version numbers. Though I suppose if we have both we might have to deal with accidental conflicts between the two. We would need a binutils patch first. This can be fixed later if it makes sense to do it. Jim
